summaryrefslogblamecommitdiff
path: root/drivers/gpu/drm/i915/intel_pm.c
blob: 3f58d7aeb70a7dbf001fcf69c9078bd90b2984b9 (plain) (tree)
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170


























                                                                               
                          

                      

                                            
 


                                                                            
  

                                                                    
  

                                                               

   
                                                    




















                                                                                
                                                                          









































                                                                               
                                                    





                                                             
                                                                         

























                                                                               
                                                   













                                                             
                                                   

























                                                               
                                                                              




































                                                                               
                                                        













                                                             
                                                        







































































































































































                                                                               


                                                                 























































































































                                                                                                    










































































































                                                                             





































                                                                        
                                                                        






















                                                                         
                                                         






















                                                                          
                                                                














                                                                       
                                                                















                                                                      
                                                                














                                                              
                                                                






































































































































































































































                                                                                 
                                                      




















































































































































































































































































                                                                                    
                                                        

















































                                                                                                                            
                                                 

















































                                                                                                                            
                                                  































































                                                                              
                                                  













































































































                                                                                       
                                                  





























































































































                                                                                          
                                                      

















































































                                                                            
                                                         



































                                                                             
                                        














































































                                                                             


























                                                                              











































































                                                                              
                                                                          





















































































































                                                                                








                                                                      









                                                                           

























































                                                                              
                                                        






























































                                                                              
                                                         






















                                                                          
                   
 
























                                                           

 
                                                    


                                                             
                                       




























                                                                                


                                                                              
                            
                                        











                                                                     
                                                   
 
                                                             
                                       

                           

                                   


                     

                                                      






                                                                    








                                                                          







                                                              








                                                                   

                                                               






                                                             
                                          



                                                   



                                                            
 


                                                             

                                                                    


                                                                              














                                                  

                                              












                                                            


                                               
                                                 


                                         
                                                                                       












                                                                                









                                                                                
                                                      


                                                                                                              
                                                                    

















                                               

 
                                                         
 
                                                             



                                           

                                                      










                                                                              





























                                                                               




























































                                                                                     
                                                              







                                                                            

                                                      
                                      
                
                       




                                                                           
                                        

                                           


                       










                                                                      





                                                                             
                                         


                                                                             




                                                                      

 














                                                    





























































































































































































































































































































































































































































































                                                                               
                                                   





































































                                                                               



                                                       
                                                                  




                                                      



                                          
                                                                           

                                           


         
                                                              



































































                                                                      
                                                          














                                                             
                                
                                                                       














                                                                      


                                                     

                                
                                                    


























                                                              


                                                      



















                                                                              

















































                                                                               









                                                                              

 
                                                               



                                                             
                       






                                                   















                                                                               
















                                                                      











                                                                   


                                                      
                                                  



                                                                          




                                              

 
                                                                










                                                             


















                                                                               


                                                      


















                                                                      
                                                    



                                                     

                                                                   






                                                           

                                                                          












                                                                       

 
                                                         
















                                                               
                                                               









                                                                
                                                                










                                                                
                                                          






                                                               


                                                                            

 
                                                          





                                                             
                                                          





                                                              
                                                         










                                                                         
                                                         


























                                                                                


















                                                             


                                                                                          













                                                             






























                                                                                             





















                                                                             





                                                

                                        























                                                                                                  
                                                                         










                                                                                                  
                                                                         



                                                                                                  
                                                                                                  




                                                                                      
                                                                                        
                                                                         





                                                                   












































                                                                                           




                                                                                   

 






























































































































































































                                                                                                                 
/*
 * Copyright © 2012 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 * Authors:
 *    Eugeni Dodonov <eugeni.dodonov@intel.com>
 *
 */

#include <linux/cpufreq.h>
#include "i915_drv.h"
#include "intel_drv.h"
#include "../../../platform/x86/intel_ips.h"
#include <linux/module.h>

/* FBC, or Frame Buffer Compression, is a technique employed to compress the
 * framebuffer contents in-memory, aiming at reducing the required bandwidth
 * during in-memory transfers and, therefore, reduce the power packet.
 *
 * The benefits of FBC are mostly visible with solid backgrounds and
 * variation-less patterns.
 *
 * FBC-related functionality can be enabled by the means of the
 * i915.i915_enable_fbc parameter
 */

static void i8xx_disable_fbc(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 fbc_ctl;

	/* Disable compression */
	fbc_ctl = I915_READ(FBC_CONTROL);
	if ((fbc_ctl & FBC_CTL_EN) == 0)
		return;

	fbc_ctl &= ~FBC_CTL_EN;
	I915_WRITE(FBC_CONTROL, fbc_ctl);

	/* Wait for compressing bit to clear */
	if (wait_for((I915_READ(FBC_STATUS) & FBC_STAT_COMPRESSING) == 0, 10)) {
		DRM_DEBUG_KMS("FBC idle timed out\n");
		return;
	}

	DRM_DEBUG_KMS("disabled FBC\n");
}

static void i8xx_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
{
	struct drm_device *dev = crtc->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_framebuffer *fb = crtc->fb;
	struct intel_framebuffer *intel_fb = to_intel_framebuffer(fb);
	struct drm_i915_gem_object *obj = intel_fb->obj;
	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
	int cfb_pitch;
	int plane, i;
	u32 fbc_ctl, fbc_ctl2;

	cfb_pitch = dev_priv->cfb_size / FBC_LL_SIZE;
	if (fb->pitches[0] < cfb_pitch)
		cfb_pitch = fb->pitches[0];

	/* FBC_CTL wants 64B units */
	cfb_pitch = (cfb_pitch / 64) - 1;
	plane = intel_crtc->plane == 0 ? FBC_CTL_PLANEA : FBC_CTL_PLANEB;

	/* Clear old tags */
	for (i = 0; i < (FBC_LL_SIZE / 32) + 1; i++)
		I915_WRITE(FBC_TAG + (i * 4), 0);

	/* Set it up... */
	fbc_ctl2 = FBC_CTL_FENCE_DBL | FBC_CTL_IDLE_IMM | FBC_CTL_CPU_FENCE;
	fbc_ctl2 |= plane;
	I915_WRITE(FBC_CONTROL2, fbc_ctl2);
	I915_WRITE(FBC_FENCE_OFF, crtc->y);

	/* enable it... */
	fbc_ctl = FBC_CTL_EN | FBC_CTL_PERIODIC;
	if (IS_I945GM(dev))
		fbc_ctl |= FBC_CTL_C3_IDLE; /* 945 needs special SR handling */
	fbc_ctl |= (cfb_pitch & 0xff) << FBC_CTL_STRIDE_SHIFT;
	fbc_ctl |= (interval & 0x2fff) << FBC_CTL_INTERVAL_SHIFT;
	fbc_ctl |= obj->fence_reg;
	I915_WRITE(FBC_CONTROL, fbc_ctl);

	DRM_DEBUG_KMS("enabled FBC, pitch %d, yoff %d, plane %d, ",
		      cfb_pitch, crtc->y, intel_crtc->plane);
}

static bool i8xx_fbc_enabled(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	return I915_READ(FBC_CONTROL) & FBC_CTL_EN;
}

static void g4x_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
{
	struct drm_device *dev = crtc->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_framebuffer *fb = crtc->fb;
	struct intel_framebuffer *intel_fb = to_intel_framebuffer(fb);
	struct drm_i915_gem_object *obj = intel_fb->obj;
	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
	int plane = intel_crtc->plane == 0 ? DPFC_CTL_PLANEA : DPFC_CTL_PLANEB;
	unsigned long stall_watermark = 200;
	u32 dpfc_ctl;

	dpfc_ctl = plane | DPFC_SR_EN | DPFC_CTL_LIMIT_1X;
	dpfc_ctl |= DPFC_CTL_FENCE_EN | obj->fence_reg;
	I915_WRITE(DPFC_CHICKEN, DPFC_HT_MODIFY);

	I915_WRITE(DPFC_RECOMP_CTL, DPFC_RECOMP_STALL_EN |
		   (stall_watermark << DPFC_RECOMP_STALL_WM_SHIFT) |
		   (interval << DPFC_RECOMP_TIMER_COUNT_SHIFT));
	I915_WRITE(DPFC_FENCE_YOFF, crtc->y);

	/* enable it... */
	I915_WRITE(DPFC_CONTROL, I915_READ(DPFC_CONTROL) | DPFC_CTL_EN);

	DRM_DEBUG_KMS("enabled fbc on plane %d\n", intel_crtc->plane);
}

static void g4x_disable_fbc(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 dpfc_ctl;

	/* Disable compression */
	dpfc_ctl = I915_READ(DPFC_CONTROL);
	if (dpfc_ctl & DPFC_CTL_EN) {
		dpfc_ctl &= ~DPFC_CTL_EN;
		I915_WRITE(DPFC_CONTROL, dpfc_ctl);

		DRM_DEBUG_KMS("disabled FBC\n");
	}
}

static bool g4x_fbc_enabled(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	return I915_READ(DPFC_CONTROL) & DPFC_CTL_EN;
}

static void sandybridge_blit_fbc_update(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 blt_ecoskpd;

	/* Make sure blitter notifies FBC of writes */
	gen6_gt_force_wake_get(dev_priv);
	blt_ecoskpd = I915_READ(GEN6_BLITTER_ECOSKPD);
	blt_ecoskpd |= GEN6_BLITTER_FBC_NOTIFY <<
		GEN6_BLITTER_LOCK_SHIFT;
	I915_WRITE(GEN6_BLITTER_ECOSKPD, blt_ecoskpd);
	blt_ecoskpd |= GEN6_BLITTER_FBC_NOTIFY;
	I915_WRITE(GEN6_BLITTER_ECOSKPD, blt_ecoskpd);
	blt_ecoskpd &= ~(GEN6_BLITTER_FBC_NOTIFY <<
			 GEN6_BLITTER_LOCK_SHIFT);
	I915_WRITE(GEN6_BLITTER_ECOSKPD, blt_ecoskpd);
	POSTING_READ(GEN6_BLITTER_ECOSKPD);
	gen6_gt_force_wake_put(dev_priv);
}

static void ironlake_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
{
	struct drm_device *dev = crtc->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_framebuffer *fb = crtc->fb;
	struct intel_framebuffer *intel_fb = to_intel_framebuffer(fb);
	struct drm_i915_gem_object *obj = intel_fb->obj;
	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
	int plane = intel_crtc->plane == 0 ? DPFC_CTL_PLANEA : DPFC_CTL_PLANEB;
	unsigned long stall_watermark = 200;
	u32 dpfc_ctl;

	dpfc_ctl = I915_READ(ILK_DPFC_CONTROL);
	dpfc_ctl &= DPFC_RESERVED;
	dpfc_ctl |= (plane | DPFC_CTL_LIMIT_1X);
	/* Set persistent mode for front-buffer rendering, ala X. */
	dpfc_ctl |= DPFC_CTL_PERSISTENT_MODE;
	dpfc_ctl |= (DPFC_CTL_FENCE_EN | obj->fence_reg);
	I915_WRITE(ILK_DPFC_CHICKEN, DPFC_HT_MODIFY);

	I915_WRITE(ILK_DPFC_RECOMP_CTL, DPFC_RECOMP_STALL_EN |
		   (stall_watermark << DPFC_RECOMP_STALL_WM_SHIFT) |
		   (interval << DPFC_RECOMP_TIMER_COUNT_SHIFT));
	I915_WRITE(ILK_DPFC_FENCE_YOFF, crtc->y);
	I915_WRITE(ILK_FBC_RT_BASE, obj->gtt_offset | ILK_FBC_RT_VALID);
	/* enable it... */
	I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);

	if (IS_GEN6(dev)) {
		I915_WRITE(SNB_DPFC_CTL_SA,
			   SNB_CPU_FENCE_ENABLE | obj->fence_reg);
		I915_WRITE(DPFC_CPU_FENCE_OFFSET, crtc->y);
		sandybridge_blit_fbc_update(dev);
	}

	DRM_DEBUG_KMS("enabled fbc on plane %d\n", intel_crtc->plane);
}

static void ironlake_disable_fbc(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 dpfc_ctl;

	/* Disable compression */
	dpfc_ctl = I915_READ(ILK_DPFC_CONTROL);
	if (dpfc_ctl & DPFC_CTL_EN) {
		dpfc_ctl &= ~DPFC_CTL_EN;
		I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl);

		DRM_DEBUG_KMS("disabled FBC\n");
	}
}

static bool ironlake_fbc_enabled(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	return I915_READ(ILK_DPFC_CONTROL) & DPFC_CTL_EN;
}

bool intel_fbc_enabled(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (!dev_priv->display.fbc_enabled)
		return false;

	return dev_priv->display.fbc_enabled(dev);
}

static void intel_fbc_work_fn(struct work_struct *__work)
{
	struct intel_fbc_work *work =
		container_of(to_delayed_work(__work),
			     struct intel_fbc_work, work);
	struct drm_device *dev = work->crtc->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;

	mutex_lock(&dev->struct_mutex);
	if (work == dev_priv->fbc_work) {
		/* Double check that we haven't switched fb without cancelling
		 * the prior work.
		 */
		if (work->crtc->fb == work->fb) {
			dev_priv->display.enable_fbc(work->crtc,
						     work->interval);

			dev_priv->cfb_plane = to_intel_crtc(work->crtc)->plane;
			dev_priv->cfb_fb = work->crtc->fb->base.id;
			dev_priv->cfb_y = work->crtc->y;
		}

		dev_priv->fbc_work = NULL;
	}
	mutex_unlock(&dev->struct_mutex);

	kfree(work);
}

static void intel_cancel_fbc_work(struct drm_i915_private *dev_priv)
{
	if (dev_priv->fbc_work == NULL)
		return;

	DRM_DEBUG_KMS("cancelling pending FBC enable\n");

	/* Synchronisation is provided by struct_mutex and checking of
	 * dev_priv->fbc_work, so we can perform the cancellation
	 * entirely asynchronously.
	 */
	if (cancel_delayed_work(&dev_priv->fbc_work->work))
		/* tasklet was killed before being run, clean up */
		kfree(dev_priv->fbc_work);

	/* Mark the work as no longer wanted so that if it does
	 * wake-up (because the work was already running and waiting
	 * for our mutex), it will discover that is no longer
	 * necessary to run.
	 */
	dev_priv->fbc_work = NULL;
}

void intel_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
{
	struct intel_fbc_work *work;
	struct drm_device *dev = crtc->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (!dev_priv->display.enable_fbc)
		return;

	intel_cancel_fbc_work(dev_priv);

	work = kzalloc(sizeof *work, GFP_KERNEL);
	if (work == NULL) {
		dev_priv->display.enable_fbc(crtc, interval);
		return;
	}

	work->crtc = crtc;
	work->fb = crtc->fb;
	work->interval = interval;
	INIT_DELAYED_WORK(&work->work, intel_fbc_work_fn);

	dev_priv->fbc_work = work;

	DRM_DEBUG_KMS("scheduling delayed FBC enable\n");

	/* Delay the actual enabling to let pageflipping cease and the
	 * display to settle before starting the compression. Note that
	 * this delay also serves a second purpose: it allows for a
	 * vblank to pass after disabling the FBC before we attempt
	 * to modify the control registers.
	 *
	 * A more complicated solution would involve tracking vblanks
	 * following the termination of the page-flipping sequence
	 * and indeed performing the enable as a co-routine and not
	 * waiting synchronously upon the vblank.
	 */
	schedule_delayed_work(&work->work, msecs_to_jiffies(50));
}

void intel_disable_fbc(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	intel_cancel_fbc_work(dev_priv);

	if (!dev_priv->display.disable_fbc)
		return;

	dev_priv->display.disable_fbc(dev);
	dev_priv->cfb_plane = -1;
}

/**
 * intel_update_fbc - enable/disable FBC as needed
 * @dev: the drm_device
 *
 * Set up the framebuffer compression hardware at mode set time.  We
 * enable it if possible:
 *   - plane A only (on pre-965)
 *   - no pixel mulitply/line duplication
 *   - no alpha buffer discard
 *   - no dual wide
 *   - framebuffer <= 2048 in width, 1536 in height
 *
 * We can't assume that any compression will take place (worst case),
 * so the compressed buffer has to be the same size as the uncompressed
 * one.  It also must reside (along with the line length buffer) in
 * stolen memory.
 *
 * We need to enable/disable FBC on a global basis.
 */
void intel_update_fbc(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_crtc *crtc = NULL, *tmp_crtc;
	struct intel_crtc *intel_crtc;
	struct drm_framebuffer *fb;
	struct intel_framebuffer *intel_fb;
	struct drm_i915_gem_object *obj;
	int enable_fbc;

	DRM_DEBUG_KMS("\n");

	if (!i915_powersave)
		return;

	if (!I915_HAS_FBC(dev))
		return;

	/*
	 * If FBC is already on, we just have to verify that we can
	 * keep it that way...
	 * Need to disable if:
	 *   - more than one pipe is active
	 *   - changing FBC params (stride, fence, mode)
	 *   - new fb is too large to fit in compressed buffer
	 *   - going to an unsupported config (interlace, pixel multiply, etc.)
	 */
	list_for_each_entry(tmp_crtc, &dev->mode_config.crtc_list, head) {
		if (tmp_crtc->enabled &&
		    !to_intel_crtc(tmp_crtc)->primary_disabled &&
		    tmp_crtc->fb) {
			if (crtc) {
				DRM_DEBUG_KMS("more than one pipe active, disabling compression\n");
				dev_priv->no_fbc_reason = FBC_MULTIPLE_PIPES;
				goto out_disable;
			}
			crtc = tmp_crtc;
		}
	}

	if (!crtc || crtc->fb == NULL) {
		DRM_DEBUG_KMS("no output, disabling\n");
		dev_priv->no_fbc_reason = FBC_NO_OUTPUT;
		goto out_disable;
	}

	intel_crtc = to_intel_crtc(crtc);
	fb = crtc->fb;
	intel_fb = to_intel_framebuffer(fb);
	obj = intel_fb->obj;

	enable_fbc = i915_enable_fbc;
	if (enable_fbc < 0) {
		DRM_DEBUG_KMS("fbc set to per-chip default\n");
		enable_fbc = 1;
		if (INTEL_INFO(dev)->gen <= 6)
			enable_fbc = 0;
	}
	if (!enable_fbc) {
		DRM_DEBUG_KMS("fbc disabled per module param\n");
		dev_priv->no_fbc_reason = FBC_MODULE_PARAM;
		goto out_disable;
	}
	if (intel_fb->obj->base.size > dev_priv->cfb_size) {
		DRM_DEBUG_KMS("framebuffer too large, disabling "
			      "compression\n");
		dev_priv->no_fbc_reason = FBC_STOLEN_TOO_SMALL;
		goto out_disable;
	}
	if ((crtc->mode.flags & DRM_MODE_FLAG_INTERLACE) ||
	    (crtc->mode.flags & DRM_MODE_FLAG_DBLSCAN)) {
		DRM_DEBUG_KMS("mode incompatible with compression, "
			      "disabling\n");
		dev_priv->no_fbc_reason = FBC_UNSUPPORTED_MODE;
		goto out_disable;
	}
	if ((crtc->mode.hdisplay > 2048) ||
	    (crtc->mode.vdisplay > 1536)) {
		DRM_DEBUG_KMS("mode too large for compression, disabling\n");
		dev_priv->no_fbc_reason = FBC_MODE_TOO_LARGE;
		goto out_disable;
	}
	if ((IS_I915GM(dev) || IS_I945GM(dev)) && intel_crtc->plane != 0) {
		DRM_DEBUG_KMS("plane not 0, disabling compression\n");
		dev_priv->no_fbc_reason = FBC_BAD_PLANE;
		goto out_disable;
	}

	/* The use of a CPU fence is mandatory in order to detect writes
	 * by the CPU to the scanout and trigger updates to the FBC.
	 */
	if (obj->tiling_mode != I915_TILING_X ||
	    obj->fence_reg == I915_FENCE_REG_NONE) {
		DRM_DEBUG_KMS("framebuffer not tiled or fenced, disabling compression\n");
		dev_priv->no_fbc_reason = FBC_NOT_TILED;
		goto out_disable;
	}

	/* If the kernel debugger is active, always disable compression */
	if (in_dbg_master())
		goto out_disable;

	/* If the scanout has not changed, don't modify the FBC settings.
	 * Note that we make the fundamental assumption that the fb->obj
	 * cannot be unpinned (and have its GTT offset and fence revoked)
	 * without first being decoupled from the scanout and FBC disabled.
	 */
	if (dev_priv->cfb_plane == intel_crtc->plane &&
	    dev_priv->cfb_fb == fb->base.id &&
	    dev_priv->cfb_y == crtc->y)
		return;

	if (intel_fbc_enabled(dev)) {
		/* We update FBC along two paths, after changing fb/crtc
		 * configuration (modeswitching) and after page-flipping
		 * finishes. For the latter, we know that not only did
		 * we disable the FBC at the start of the page-flip
		 * sequence, but also more than one vblank has passed.
		 *
		 * For the former case of modeswitching, it is possible
		 * to switch between two FBC valid configurations
		 * instantaneously so we do need to disable the FBC
		 * before we can modify its control registers. We also
		 * have to wait for the next vblank for that to take
		 * effect. However, since we delay enabling FBC we can
		 * assume that a vblank has passed since disabling and
		 * that we can safely alter the registers in the deferred
		 * callback.
		 *
		 * In the scenario that we go from a valid to invalid
		 * and then back to valid FBC configuration we have
		 * no strict enforcement that a vblank occurred since
		 * disabling the FBC. However, along all current pipe
		 * disabling paths we do need to wait for a vblank at
		 * some point. And we wait before enabling FBC anyway.
		 */
		DRM_DEBUG_KMS("disabling active FBC for update\n");
		intel_disable_fbc(dev);
	}

	intel_enable_fbc(crtc, 500);
	return;

out_disable:
	/* Multiple disables should be harmless */
	if (intel_fbc_enabled(dev)) {
		DRM_DEBUG_KMS("unsupported config, disabling FBC\n");
		intel_disable_fbc(dev);
	}
}

static void i915_pineview_get_mem_freq(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	u32 tmp;

	tmp = I915_READ(CLKCFG);

	switch (tmp & CLKCFG_FSB_MASK) {
	case CLKCFG_FSB_533:
		dev_priv->fsb_freq = 533; /* 133*4 */
		break;
	case CLKCFG_FSB_800:
		dev_priv->fsb_freq = 800; /* 200*4 */
		break;
	case CLKCFG_FSB_667:
		dev_priv->fsb_freq =  667; /* 167*4 */
		break;
	case CLKCFG_FSB_400:
		dev_priv->fsb_freq = 400; /* 100*4 */
		break;
	}

	switch (tmp & CLKCFG_MEM_MASK) {
	case CLKCFG_MEM_533:
		dev_priv->mem_freq = 533;
		break;
	case CLKCFG_MEM_667:
		dev_priv->mem_freq = 667;
		break;
	case CLKCFG_MEM_800:
		dev_priv->mem_freq = 800;
		break;
	}

	/* detect pineview DDR3 setting */
	tmp = I915_READ(CSHRDDR3CTL);
	dev_priv->is_ddr3 = (tmp & CSHRDDR3CTL_DDR3) ? 1 : 0;
}

static void i915_ironlake_get_mem_freq(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	u16 ddrpll, csipll;

	ddrpll = I915_READ16(DDRMPLL1);
	csipll = I915_READ16(CSIPLL0);

	switch (ddrpll & 0xff) {
	case 0xc:
		dev_priv->mem_freq = 800;
		break;
	case 0x10:
		dev_priv->mem_freq = 1066;
		break;
	case 0x14:
		dev_priv->mem_freq = 1333;
		break;
	case 0x18:
		dev_priv->mem_freq = 1600;
		break;
	default:
		DRM_DEBUG_DRIVER("unknown memory frequency 0x%02x\n",
				 ddrpll & 0xff);
		dev_priv->mem_freq = 0;
		break;
	}

	dev_priv->r_t = dev_priv->mem_freq;

	switch (csipll & 0x3ff) {
	case 0x00c:
		dev_priv->fsb_freq = 3200;
		break;
	case 0x00e:
		dev_priv->fsb_freq = 3733;
		break;
	case 0x010:
		dev_priv->fsb_freq = 4266;
		break;
	case 0x012:
		dev_priv->fsb_freq = 4800;
		break;
	case 0x014:
		dev_priv->fsb_freq = 5333;
		break;
	case 0x016:
		dev_priv->fsb_freq = 5866;
		break;
	case 0x018:
		dev_priv->fsb_freq = 6400;
		break;
	default:
		DRM_DEBUG_DRIVER("unknown fsb frequency 0x%04x\n",
				 csipll & 0x3ff);
		dev_priv->fsb_freq = 0;
		break;
	}

	if (dev_priv->fsb_freq == 3200) {
		dev_priv->c_m = 0;
	} else if (dev_priv->fsb_freq > 3200 && dev_priv->fsb_freq <= 4800) {
		dev_priv->c_m = 1;
	} else {
		dev_priv->c_m = 2;
	}
}

static const struct cxsr_latency cxsr_latency_table[] = {
	{1, 0, 800, 400, 3382, 33382, 3983, 33983},    /* DDR2-400 SC */
	{1, 0, 800, 667, 3354, 33354, 3807, 33807},    /* DDR2-667 SC */
	{1, 0, 800, 800, 3347, 33347, 3763, 33763},    /* DDR2-800 SC */
	{1, 1, 800, 667, 6420, 36420, 6873, 36873},    /* DDR3-667 SC */
	{1, 1, 800, 800, 5902, 35902, 6318, 36318},    /* DDR3-800 SC */

	{1, 0, 667, 400, 3400, 33400, 4021, 34021},    /* DDR2-400 SC */
	{1, 0, 667, 667, 3372, 33372, 3845, 33845},    /* DDR2-667 SC */
	{1, 0, 667, 800, 3386, 33386, 3822, 33822},    /* DDR2-800 SC */
	{1, 1, 667, 667, 6438, 36438, 6911, 36911},    /* DDR3-667 SC */
	{1, 1, 667, 800, 5941, 35941, 6377, 36377},    /* DDR3-800 SC */

	{1, 0, 400, 400, 3472, 33472, 4173, 34173},    /* DDR2-400 SC */
	{1, 0, 400, 667, 3443, 33443, 3996, 33996},    /* DDR2-667 SC */
	{1, 0, 400, 800, 3430, 33430, 3946, 33946},    /* DDR2-800 SC */
	{1, 1, 400, 667, 6509, 36509, 7062, 37062},    /* DDR3-667 SC */
	{1, 1, 400, 800, 5985, 35985, 6501, 36501},    /* DDR3-800 SC */

	{0, 0, 800, 400, 3438, 33438, 4065, 34065},    /* DDR2-400 SC */
	{0, 0, 800, 667, 3410, 33410, 3889, 33889},    /* DDR2-667 SC */
	{0, 0, 800, 800, 3403, 33403, 3845, 33845},    /* DDR2-800 SC */
	{0, 1, 800, 667, 6476, 36476, 6955, 36955},    /* DDR3-667 SC */
	{0, 1, 800, 800, 5958, 35958, 6400, 36400},    /* DDR3-800 SC */

	{0, 0, 667, 400, 3456, 33456, 4103, 34106},    /* DDR2-400 SC */
	{0, 0, 667, 667, 3428, 33428, 3927, 33927},    /* DDR2-667 SC */
	{0, 0, 667, 800, 3443, 33443, 3905, 33905},    /* DDR2-800 SC */
	{0, 1, 667, 667, 6494, 36494, 6993, 36993},    /* DDR3-667 SC */
	{0, 1, 667, 800, 5998, 35998, 6460, 36460},    /* DDR3-800 SC */

	{0, 0, 400, 400, 3528, 33528, 4255, 34255},    /* DDR2-400 SC */
	{0, 0, 400, 667, 3500, 33500, 4079, 34079},    /* DDR2-667 SC */
	{0, 0, 400, 800, 3487, 33487, 4029, 34029},    /* DDR2-800 SC */
	{0, 1, 400, 667, 6566, 36566, 7145, 37145},    /* DDR3-667 SC */
	{0, 1, 400, 800, 6042, 36042, 6584, 36584},    /* DDR3-800 SC */
};

static const struct cxsr_latency *intel_get_cxsr_latency(int is_desktop,
							 int is_ddr3,
							 int fsb,
							 int mem)
{
	const struct cxsr_latency *latency;
	int i;

	if (fsb == 0 || mem == 0)
		return NULL;

	for (i = 0; i < ARRAY_SIZE(cxsr_latency_table); i++) {
		latency = &cxsr_latency_table[i];
		if (is_desktop == latency->is_desktop &&
		    is_ddr3 == latency->is_ddr3 &&
		    fsb == latency->fsb_freq && mem == latency->mem_freq)
			return latency;
	}

	DRM_DEBUG_KMS("Unknown FSB/MEM found, disable CxSR\n");

	return NULL;
}

static void pineview_disable_cxsr(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	/* deactivate cxsr */
	I915_WRITE(DSPFW3, I915_READ(DSPFW3) & ~PINEVIEW_SELF_REFRESH_EN);
}

/*
 * Latency for FIFO fetches is dependent on several factors:
 *   - memory configuration (speed, channels)
 *   - chipset
 *   - current MCH state
 * It can be fairly high in some situations, so here we assume a fairly
 * pessimal value.  It's a tradeoff between extra memory fetches (if we
 * set this value too high, the FIFO will fetch frequently to stay full)
 * and power consumption (set it too low to save power and we might see
 * FIFO underruns and display "flicker").
 *
 * A value of 5us seems to be a good balance; safe for very low end
 * platforms but not overly aggressive on lower latency configs.
 */
static const int latency_ns = 5000;

static int i9xx_get_fifo_size(struct drm_device *dev, int plane)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	uint32_t dsparb = I915_READ(DSPARB);
	int size;

	size = dsparb & 0x7f;
	if (plane)
		size = ((dsparb >> DSPARB_CSTART_SHIFT) & 0x7f) - size;

	DRM_DEBUG_KMS("FIFO size - (0x%08x) %s: %d\n", dsparb,
		      plane ? "B" : "A", size);

	return size;
}

static int i85x_get_fifo_size(struct drm_device *dev, int plane)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	uint32_t dsparb = I915_READ(DSPARB);
	int size;

	size = dsparb & 0x1ff;
	if (plane)
		size = ((dsparb >> DSPARB_BEND_SHIFT) & 0x1ff) - size;
	size >>= 1; /* Convert to cachelines */

	DRM_DEBUG_KMS("FIFO size - (0x%08x) %s: %d\n", dsparb,
		      plane ? "B" : "A", size);

	return size;
}

static int i845_get_fifo_size(struct drm_device *dev, int plane)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	uint32_t dsparb = I915_READ(DSPARB);
	int size;

	size = dsparb & 0x7f;
	size >>= 2; /* Convert to cachelines */

	DRM_DEBUG_KMS("FIFO size - (0x%08x) %s: %d\n", dsparb,
		      plane ? "B" : "A",
		      size);

	return size;
}

static int i830_get_fifo_size(struct drm_device *dev, int plane)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	uint32_t dsparb = I915_READ(DSPARB);
	int size;

	size = dsparb & 0x7f;
	size >>= 1; /* Convert to cachelines */

	DRM_DEBUG_KMS("FIFO size - (0x%08x) %s: %d\n", dsparb,
		      plane ? "B" : "A", size);

	return size;
}

/* Pineview has different values for various configs */
static const struct intel_watermark_params pineview_display_wm = {
	PINEVIEW_DISPLAY_FIFO,
	PINEVIEW_MAX_WM,
	PINEVIEW_DFT_WM,
	PINEVIEW_GUARD_WM,
	PINEVIEW_FIFO_LINE_SIZE
};
static const struct intel_watermark_params pineview_display_hplloff_wm = {
	PINEVIEW_DISPLAY_FIFO,
	PINEVIEW_MAX_WM,
	PINEVIEW_DFT_HPLLOFF_WM,
	PINEVIEW_GUARD_WM,
	PINEVIEW_FIFO_LINE_SIZE
};
static const struct intel_watermark_params pineview_cursor_wm = {
	PINEVIEW_CURSOR_FIFO,
	PINEVIEW_CURSOR_MAX_WM,
	PINEVIEW_CURSOR_DFT_WM,
	PINEVIEW_CURSOR_GUARD_WM,
	PINEVIEW_FIFO_LINE_SIZE,
};
static const struct intel_watermark_params pineview_cursor_hplloff_wm = {
	PINEVIEW_CURSOR_FIFO,
	PINEVIEW_CURSOR_MAX_WM,
	PINEVIEW_CURSOR_DFT_WM,
	PINEVIEW_CURSOR_GUARD_WM,
	PINEVIEW_FIFO_LINE_SIZE
};
static const struct intel_watermark_params g4x_wm_info = {
	G4X_FIFO_SIZE,
	G4X_MAX_WM,
	G4X_MAX_WM,
	2,
	G4X_FIFO_LINE_SIZE,
};
static const struct intel_watermark_params g4x_cursor_wm_info = {
	I965_CURSOR_FIFO,
	I965_CURSOR_MAX_WM,
	I965_CURSOR_DFT_WM,
	2,
	G4X_FIFO_LINE_SIZE,
};
static const struct intel_watermark_params valleyview_wm_info = {
	VALLEYVIEW_FIFO_SIZE,
	VALLEYVIEW_MAX_WM,
	VALLEYVIEW_MAX_WM,
	2,
	G4X_FIFO_LINE_SIZE,
};
static const struct intel_watermark_params valleyview_cursor_wm_info = {
	I965_CURSOR_FIFO,
	VALLEYVIEW_CURSOR_MAX_WM,
	I965_CURSOR_DFT_WM,
	2,
	G4X_FIFO_LINE_SIZE,
};
static const struct intel_watermark_params i965_cursor_wm_info = {
	I965_CURSOR_FIFO,
	I965_CURSOR_MAX_WM,
	I965_CURSOR_DFT_WM,
	2,
	I915_FIFO_LINE_SIZE,
};
static const struct intel_watermark_params i945_wm_info = {
	I945_FIFO_SIZE,
	I915_MAX_WM,
	1,
	2,
	I915_FIFO_LINE_SIZE
};
static const struct intel_watermark_params i915_wm_info = {
	I915_FIFO_SIZE,
	I915_MAX_WM,
	1,
	2,
	I915_FIFO_LINE_SIZE
};
static const struct intel_watermark_params i855_wm_info = {
	I855GM_FIFO_SIZE,
	I915_MAX_WM,
	1,
	2,
	I830_FIFO_LINE_SIZE
};
static const struct intel_watermark_params i830_wm_info = {
	I830_FIFO_SIZE,
	I915_MAX_WM,
	1,
	2,
	I830_FIFO_LINE_SIZE
};

static const struct intel_watermark_params ironlake_display_wm_info = {
	ILK_DISPLAY_FIFO,
	ILK_DISPLAY_MAXWM,
	ILK_DISPLAY_DFTWM,
	2,
	ILK_FIFO_LINE_SIZE
};
static const struct intel_watermark_params ironlake_cursor_wm_info = {
	ILK_CURSOR_FIFO,
	ILK_CURSOR_MAXWM,
	ILK_CURSOR_DFTWM,
	2,
	ILK_FIFO_LINE_SIZE
};
static const struct intel_watermark_params ironlake_display_srwm_info = {
	ILK_DISPLAY_SR_FIFO,
	ILK_DISPLAY_MAX_SRWM,
	ILK_DISPLAY_DFT_SRWM,
	2,
	ILK_FIFO_LINE_SIZE
};
static const struct intel_watermark_params ironlake_cursor_srwm_info = {
	ILK_CURSOR_SR_FIFO,
	ILK_CURSOR_MAX_SRWM,
	ILK_CURSOR_DFT_SRWM,
	2,
	ILK_FIFO_LINE_SIZE
};

static const struct intel_watermark_params sandybridge_display_wm_info = {
	SNB_DISPLAY_FIFO,
	SNB_DISPLAY_MAXWM,
	SNB_DISPLAY_DFTWM,
	2,
	SNB_FIFO_LINE_SIZE
};
static const struct intel_watermark_params sandybridge_cursor_wm_info = {
	SNB_CURSOR_FIFO,
	SNB_CURSOR_MAXWM,
	SNB_CURSOR_DFTWM,
	2,
	SNB_FIFO_LINE_SIZE
};
static const struct intel_watermark_params sandybridge_display_srwm_info = {
	SNB_DISPLAY_SR_FIFO,
	SNB_DISPLAY_MAX_SRWM,
	SNB_DISPLAY_DFT_SRWM,
	2,
	SNB_FIFO_LINE_SIZE
};
static const struct intel_watermark_params sandybridge_cursor_srwm_info = {
	SNB_CURSOR_SR_FIFO,
	SNB_CURSOR_MAX_SRWM,
	SNB_CURSOR_DFT_SRWM,
	2,
	SNB_FIFO_LINE_SIZE
};


/**
 * intel_calculate_wm - calculate watermark level
 * @clock_in_khz: pixel clock
 * @wm: chip FIFO params
 * @pixel_size: display pixel size
 * @latency_ns: memory latency for the platform
 *
 * Calculate the watermark level (the level at which the display plane will
 * start fetching from memory again).  Each chip has a different display
 * FIFO size and allocation, so the caller needs to figure that out and pass
 * in the correct intel_watermark_params structure.
 *
 * As the pixel clock runs, the FIFO will be drained at a rate that depends
 * on the pixel size.  When it reaches the watermark level, it'll start
 * fetching FIFO line sized based chunks from memory until the FIFO fills
 * past the watermark point.  If the FIFO drains completely, a FIFO underrun
 * will occur, and a display engine hang could result.
 */
static unsigned long intel_calculate_wm(unsigned long clock_in_khz,
					const struct intel_watermark_params *wm,
					int fifo_size,
					int pixel_size,
					unsigned long latency_ns)
{
	long entries_required, wm_size;

	/*
	 * Note: we need to make sure we don't overflow for various clock &
	 * latency values.
	 * clocks go from a few thousand to several hundred thousand.
	 * latency is usually a few thousand
	 */
	entries_required = ((clock_in_khz / 1000) * pixel_size * latency_ns) /
		1000;
	entries_required = DIV_ROUND_UP(entries_required, wm->cacheline_size);

	DRM_DEBUG_KMS("FIFO entries required for mode: %ld\n", entries_required);

	wm_size = fifo_size - (entries_required + wm->guard_size);

	DRM_DEBUG_KMS("FIFO watermark level: %ld\n", wm_size);

	/* Don't promote wm_size to unsigned... */
	if (wm_size > (long)wm->max_wm)
		wm_size = wm->max_wm;
	if (wm_size <= 0)
		wm_size = wm->default_wm;
	return wm_size;
}

static struct drm_crtc *single_enabled_crtc(struct drm_device *dev)
{
	struct drm_crtc *crtc, *enabled = NULL;

	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
		if (crtc->enabled && crtc->fb) {
			if (enabled)
				return NULL;
			enabled = crtc;
		}
	}

	return enabled;
}

static void pineview_update_wm(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_crtc *crtc;
	const struct cxsr_latency *latency;
	u32 reg;
	unsigned long wm;

	latency = intel_get_cxsr_latency(IS_PINEVIEW_G(dev), dev_priv->is_ddr3,
					 dev_priv->fsb_freq, dev_priv->mem_freq);
	if (!latency) {
		DRM_DEBUG_KMS("Unknown FSB/MEM found, disable CxSR\n");
		pineview_disable_cxsr(dev);
		return;
	}

	crtc = single_enabled_crtc(dev);
	if (crtc) {
		int clock = crtc->mode.clock;
		int pixel_size = crtc->fb->bits_per_pixel / 8;

		/* Display SR */
		wm = intel_calculate_wm(clock, &pineview_display_wm,
					pineview_display_wm.fifo_size,
					pixel_size, latency->display_sr);
		reg = I915_READ(DSPFW1);
		reg &= ~DSPFW_SR_MASK;
		reg |= wm << DSPFW_SR_SHIFT;
		I915_WRITE(DSPFW1, reg);
		DRM_DEBUG_KMS("DSPFW1 register is %x\n", reg);

		/* cursor SR */
		wm = intel_calculate_wm(clock, &pineview_cursor_wm,
					pineview_display_wm.fifo_size,
					pixel_size, latency->cursor_sr);
		reg = I915_READ(DSPFW3);
		reg &= ~DSPFW_CURSOR_SR_MASK;
		reg |= (wm & 0x3f) << DSPFW_CURSOR_SR_SHIFT;
		I915_WRITE(DSPFW3, reg);

		/* Display HPLL off SR */
		wm = intel_calculate_wm(clock, &pineview_display_hplloff_wm,
					pineview_display_hplloff_wm.fifo_size,
					pixel_size, latency->display_hpll_disable);
		reg = I915_READ(DSPFW3);
		reg &= ~DSPFW_HPLL_SR_MASK;
		reg |= wm & DSPFW_HPLL_SR_MASK;
		I915_WRITE(DSPFW3, reg);

		/* cursor HPLL off SR */
		wm = intel_calculate_wm(clock, &pineview_cursor_hplloff_wm,
					pineview_display_hplloff_wm.fifo_size,
					pixel_size, latency->cursor_hpll_disable);
		reg = I915_READ(DSPFW3);
		reg &= ~DSPFW_HPLL_CURSOR_MASK;
		reg |= (wm & 0x3f) << DSPFW_HPLL_CURSOR_SHIFT;
		I915_WRITE(DSPFW3, reg);
		DRM_DEBUG_KMS("DSPFW3 register is %x\n", reg);

		/* activate cxsr */
		I915_WRITE(DSPFW3,
			   I915_READ(DSPFW3) | PINEVIEW_SELF_REFRESH_EN);
		DRM_DEBUG_KMS("Self-refresh is enabled\n");
	} else {
		pineview_disable_cxsr(dev);
		DRM_DEBUG_KMS("Self-refresh is disabled\n");
	}
}

static bool g4x_compute_wm0(struct drm_device *dev,
			    int plane,
			    const struct intel_watermark_params *display,
			    int display_latency_ns,
			    const struct intel_watermark_params *cursor,
			    int cursor_latency_ns,
			    int *plane_wm,
			    int *cursor_wm)
{
	struct drm_crtc *crtc;
	int htotal, hdisplay, clock, pixel_size;
	int line_time_us, line_count;
	int entries, tlb_miss;

	crtc = intel_get_crtc_for_plane(dev, plane);
	if (crtc->fb == NULL || !crtc->enabled) {
		*cursor_wm = cursor->guard_size;
		*plane_wm = display->guard_size;
		return false;
	}

	htotal = crtc->mode.htotal;
	hdisplay = crtc->mode.hdisplay;
	clock = crtc->mode.clock;
	pixel_size = crtc->fb->bits_per_pixel / 8;

	/* Use the small buffer method to calculate plane watermark */
	entries = ((clock * pixel_size / 1000) * display_latency_ns) / 1000;
	tlb_miss = display->fifo_size*display->cacheline_size - hdisplay * 8;
	if (tlb_miss > 0)
		entries += tlb_miss;
	entries = DIV_ROUND_UP(entries, display->cacheline_size);
	*plane_wm = entries + display->guard_size;
	if (*plane_wm > (int)display->max_wm)
		*plane_wm = display->max_wm;

	/* Use the large buffer method to calculate cursor watermark */
	line_time_us = ((htotal * 1000) / clock);
	line_count = (cursor_latency_ns / line_time_us + 1000) / 1000;
	entries = line_count * 64 * pixel_size;
	tlb_miss = cursor->fifo_size*cursor->cacheline_size - hdisplay * 8;
	if (tlb_miss > 0)
		entries += tlb_miss;
	entries = DIV_ROUND_UP(entries, cursor->cacheline_size);
	*cursor_wm = entries + cursor->guard_size;
	if (*cursor_wm > (int)cursor->max_wm)
		*cursor_wm = (int)cursor->max_wm;

	return true;
}

/*
 * Check the wm result.
 *
 * If any calculated watermark values is larger than the maximum value that
 * can be programmed into the associated watermark register, that watermark
 * must be disabled.
 */
static bool g4x_check_srwm(struct drm_device *dev,
			   int display_wm, int cursor_wm,
			   const struct intel_watermark_params *display,
			   const struct intel_watermark_params *cursor)
{
	DRM_DEBUG_KMS("SR watermark: display plane %d, cursor %d\n",
		      display_wm, cursor_wm);

	if (display_wm > display->max_wm) {
		DRM_DEBUG_KMS("display watermark is too large(%d/%ld), disabling\n",
			      display_wm, display->max_wm);
		return false;
	}

	if (cursor_wm > cursor->max_wm) {
		DRM_DEBUG_KMS("cursor watermark is too large(%d/%ld), disabling\n",
			      cursor_wm, cursor->max_wm);
		return false;
	}

	if (!(display_wm || cursor_wm)) {
		DRM_DEBUG_KMS("SR latency is 0, disabling\n");
		return false;
	}

	return true;
}

static bool g4x_compute_srwm(struct drm_device *dev,
			     int plane,
			     int latency_ns,
			     const struct intel_watermark_params *display,
			     const struct intel_watermark_params *cursor,
			     int *display_wm, int *cursor_wm)
{
	struct drm_crtc *crtc;
	int hdisplay, htotal, pixel_size, clock;
	unsigned long line_time_us;
	int line_count, line_size;
	int small, large;
	int entries;

	if (!latency_ns) {
		*display_wm = *cursor_wm = 0;
		return false;
	}

	crtc = intel_get_crtc_for_plane(dev, plane);
	hdisplay = crtc->mode.hdisplay;
	htotal = crtc->mode.htotal;
	clock = crtc->mode.clock;
	pixel_size = crtc->fb->bits_per_pixel / 8;

	line_time_us = (htotal * 1000) / clock;
	line_count = (latency_ns / line_time_us + 1000) / 1000;
	line_size = hdisplay * pixel_size;

	/* Use the minimum of the small and large buffer method for primary */
	small = ((clock * pixel_size / 1000) * latency_ns) / 1000;
	large = line_count * line_size;

	entries = DIV_ROUND_UP(min(small, large), display->cacheline_size);
	*display_wm = entries + display->guard_size;

	/* calculate the self-refresh watermark for display cursor */
	entries = line_count * pixel_size * 64;
	entries = DIV_ROUND_UP(entries, cursor->cacheline_size);
	*cursor_wm = entries + cursor->guard_size;

	return g4x_check_srwm(dev,
			      *display_wm, *cursor_wm,
			      display, cursor);
}

static bool vlv_compute_drain_latency(struct drm_device *dev,
				     int plane,
				     int *plane_prec_mult,
				     int *plane_dl,
				     int *cursor_prec_mult,
				     int *cursor_dl)
{
	struct drm_crtc *crtc;
	int clock, pixel_size;
	int entries;

	crtc = intel_get_crtc_for_plane(dev, plane);
	if (crtc->fb == NULL || !crtc->enabled)
		return false;

	clock = crtc->mode.clock;	/* VESA DOT Clock */
	pixel_size = crtc->fb->bits_per_pixel / 8;	/* BPP */

	entries = (clock / 1000) * pixel_size;
	*plane_prec_mult = (entries > 256) ?
		DRAIN_LATENCY_PRECISION_32 : DRAIN_LATENCY_PRECISION_16;
	*plane_dl = (64 * (*plane_prec_mult) * 4) / ((clock / 1000) *
						     pixel_size);

	entries = (clock / 1000) * 4;	/* BPP is always 4 for cursor */
	*cursor_prec_mult = (entries > 256) ?
		DRAIN_LATENCY_PRECISION_32 : DRAIN_LATENCY_PRECISION_16;
	*cursor_dl = (64 * (*cursor_prec_mult) * 4) / ((clock / 1000) * 4);

	return true;
}

/*
 * Update drain latency registers of memory arbiter
 *
 * Valleyview SoC has a new memory arbiter and needs drain latency registers
 * to be programmed. Each plane has a drain latency multiplier and a drain
 * latency value.
 */

static void vlv_update_drain_latency(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int planea_prec, planea_dl, planeb_prec, planeb_dl;
	int cursora_prec, cursora_dl, cursorb_prec, cursorb_dl;
	int plane_prec_mult, cursor_prec_mult; /* Precision multiplier is
							either 16 or 32 */

	/* For plane A, Cursor A */
	if (vlv_compute_drain_latency(dev, 0, &plane_prec_mult, &planea_dl,
				      &cursor_prec_mult, &cursora_dl)) {
		cursora_prec = (cursor_prec_mult == DRAIN_LATENCY_PRECISION_32) ?
			DDL_CURSORA_PRECISION_32 : DDL_CURSORA_PRECISION_16;
		planea_prec = (plane_prec_mult == DRAIN_LATENCY_PRECISION_32) ?
			DDL_PLANEA_PRECISION_32 : DDL_PLANEA_PRECISION_16;

		I915_WRITE(VLV_DDL1, cursora_prec |
				(cursora_dl << DDL_CURSORA_SHIFT) |
				planea_prec | planea_dl);
	}

	/* For plane B, Cursor B */
	if (vlv_compute_drain_latency(dev, 1, &plane_prec_mult, &planeb_dl,
				      &cursor_prec_mult, &cursorb_dl)) {
		cursorb_prec = (cursor_prec_mult == DRAIN_LATENCY_PRECISION_32) ?
			DDL_CURSORB_PRECISION_32 : DDL_CURSORB_PRECISION_16;
		planeb_prec = (plane_prec_mult == DRAIN_LATENCY_PRECISION_32) ?
			DDL_PLANEB_PRECISION_32 : DDL_PLANEB_PRECISION_16;

		I915_WRITE(VLV_DDL2, cursorb_prec |
				(cursorb_dl << DDL_CURSORB_SHIFT) |
				planeb_prec | planeb_dl);
	}
}

#define single_plane_enabled(mask) is_power_of_2(mask)

static void valleyview_update_wm(struct drm_device *dev)
{
	static const int sr_latency_ns = 12000;
	struct drm_i915_private *dev_priv = dev->dev_private;
	int planea_wm, planeb_wm, cursora_wm, cursorb_wm;
	int plane_sr, cursor_sr;
	unsigned int enabled = 0;

	vlv_update_drain_latency(dev);

	if (g4x_compute_wm0(dev, 0,
			    &valleyview_wm_info, latency_ns,
			    &valleyview_cursor_wm_info, latency_ns,
			    &planea_wm, &cursora_wm))
		enabled |= 1;

	if (g4x_compute_wm0(dev, 1,
			    &valleyview_wm_info, latency_ns,
			    &valleyview_cursor_wm_info, latency_ns,
			    &planeb_wm, &cursorb_wm))
		enabled |= 2;

	plane_sr = cursor_sr = 0;
	if (single_plane_enabled(enabled) &&
	    g4x_compute_srwm(dev, ffs(enabled) - 1,
			     sr_latency_ns,
			     &valleyview_wm_info,
			     &valleyview_cursor_wm_info,
			     &plane_sr, &cursor_sr))
		I915_WRITE(FW_BLC_SELF_VLV, FW_CSPWRDWNEN);
	else
		I915_WRITE(FW_BLC_SELF_VLV,
			   I915_READ(FW_BLC_SELF_VLV) & ~FW_CSPWRDWNEN);

	DRM_DEBUG_KMS("Setting FIFO watermarks - A: plane=%d, cursor=%d, B: plane=%d, cursor=%d, SR: plane=%d, cursor=%d\n",
		      planea_wm, cursora_wm,
		      planeb_wm, cursorb_wm,
		      plane_sr, cursor_sr);

	I915_WRITE(DSPFW1,
		   (plane_sr << DSPFW_SR_SHIFT) |
		   (cursorb_wm << DSPFW_CURSORB_SHIFT) |
		   (planeb_wm << DSPFW_PLANEB_SHIFT) |
		   planea_wm);
	I915_WRITE(DSPFW2,
		   (I915_READ(DSPFW2) & DSPFW_CURSORA_MASK) |
		   (cursora_wm << DSPFW_CURSORA_SHIFT));
	I915_WRITE(DSPFW3,
		   (I915_READ(DSPFW3) | (cursor_sr << DSPFW_CURSOR_SR_SHIFT)));
}

static void g4x_update_wm(struct drm_device *dev)
{
	static const int sr_latency_ns = 12000;
	struct drm_i915_private *dev_priv = dev->dev_private;
	int planea_wm, planeb_wm, cursora_wm, cursorb_wm;
	int plane_sr, cursor_sr;
	unsigned int enabled = 0;

	if (g4x_compute_wm0(dev, 0,
			    &g4x_wm_info, latency_ns,
			    &g4x_cursor_wm_info, latency_ns,
			    &planea_wm, &cursora_wm))
		enabled |= 1;

	if (g4x_compute_wm0(dev, 1,
			    &g4x_wm_info, latency_ns,
			    &g4x_cursor_wm_info, latency_ns,
			    &planeb_wm, &cursorb_wm))
		enabled |= 2;

	plane_sr = cursor_sr = 0;
	if (single_plane_enabled(enabled) &&
	    g4x_compute_srwm(dev, ffs(enabled) - 1,
			     sr_latency_ns,
			     &g4x_wm_info,
			     &g4x_cursor_wm_info,
			     &plane_sr, &cursor_sr))
		I915_WRITE(FW_BLC_SELF, FW_BLC_SELF_EN);
	else
		I915_WRITE(FW_BLC_SELF,
			   I915_READ(FW_BLC_SELF) & ~FW_BLC_SELF_EN);

	DRM_DEBUG_KMS("Setting FIFO watermarks - A: plane=%d, cursor=%d, B: plane=%d, cursor=%d, SR: plane=%d, cursor=%d\n",
		      planea_wm, cursora_wm,
		      planeb_wm, cursorb_wm,
		      plane_sr, cursor_sr);

	I915_WRITE(DSPFW1,
		   (plane_sr << DSPFW_SR_SHIFT) |
		   (cursorb_wm << DSPFW_CURSORB_SHIFT) |
		   (planeb_wm << DSPFW_PLANEB_SHIFT) |
		   planea_wm);
	I915_WRITE(DSPFW2,
		   (I915_READ(DSPFW2) & DSPFW_CURSORA_MASK) |
		   (cursora_wm << DSPFW_CURSORA_SHIFT));
	/* HPLL off in SR has some issues on G4x... disable it */
	I915_WRITE(DSPFW3,
		   (I915_READ(DSPFW3) & ~DSPFW_HPLL_SR_EN) |
		   (cursor_sr << DSPFW_CURSOR_SR_SHIFT));
}

static void i965_update_wm(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_crtc *crtc;
	int srwm = 1;
	int cursor_sr = 16;

	/* Calc sr entries for one plane configs */
	crtc = single_enabled_crtc(dev);
	if (crtc) {
		/* self-refresh has much higher latency */
		static const int sr_latency_ns = 12000;
		int clock = crtc->mode.clock;
		int htotal = crtc->mode.htotal;
		int hdisplay = crtc->mode.hdisplay;
		int pixel_size = crtc->fb->bits_per_pixel / 8;
		unsigned long line_time_us;
		int entries;

		line_time_us = ((htotal * 1000) / clock);

		/* Use ns/us then divide to preserve precision */
		entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) *
			pixel_size * hdisplay;
		entries = DIV_ROUND_UP(entries, I915_FIFO_LINE_SIZE);
		srwm = I965_FIFO_SIZE - entries;
		if (srwm < 0)
			srwm = 1;
		srwm &= 0x1ff;
		DRM_DEBUG_KMS("self-refresh entries: %d, wm: %d\n",
			      entries, srwm);

		entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) *
			pixel_size * 64;
		entries = DIV_ROUND_UP(entries,
					  i965_cursor_wm_info.cacheline_size);
		cursor_sr = i965_cursor_wm_info.fifo_size -
			(entries + i965_cursor_wm_info.guard_size);

		if (cursor_sr > i965_cursor_wm_info.max_wm)
			cursor_sr = i965_cursor_wm_info.max_wm;

		DRM_DEBUG_KMS("self-refresh watermark: display plane %d "
			      "cursor %d\n", srwm, cursor_sr);

		if (IS_CRESTLINE(dev))
			I915_WRITE(FW_BLC_SELF, FW_BLC_SELF_EN);
	} else {
		/* Turn off self refresh if both pipes are enabled */
		if (IS_CRESTLINE(dev))
			I915_WRITE(FW_BLC_SELF, I915_READ(FW_BLC_SELF)
				   & ~FW_BLC_SELF_EN);
	}

	DRM_DEBUG_KMS("Setting FIFO watermarks - A: 8, B: 8, C: 8, SR %d\n",
		      srwm);

	/* 965 has limitations... */
	I915_WRITE(DSPFW1, (srwm << DSPFW_SR_SHIFT) |
		   (8 << 16) | (8 << 8) | (8 << 0));
	I915_WRITE(DSPFW2, (8 << 8) | (8 << 0));
	/* update cursor SR watermark */
	I915_WRITE(DSPFW3, (cursor_sr << DSPFW_CURSOR_SR_SHIFT));
}

static void i9xx_update_wm(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	const struct intel_watermark_params *wm_info;
	uint32_t fwater_lo;
	uint32_t fwater_hi;
	int cwm, srwm = 1;
	int fifo_size;
	int planea_wm, planeb_wm;
	struct drm_crtc *crtc, *enabled = NULL;

	if (IS_I945GM(dev))
		wm_info = &i945_wm_info;
	else if (!IS_GEN2(dev))
		wm_info = &i915_wm_info;
	else
		wm_info = &i855_wm_info;

	fifo_size = dev_priv->display.get_fifo_size(dev, 0);
	crtc = intel_get_crtc_for_plane(dev, 0);
	if (crtc->enabled && crtc->fb) {
		planea_wm = intel_calculate_wm(crtc->mode.clock,
					       wm_info, fifo_size,
					       crtc->fb->bits_per_pixel / 8,
					       latency_ns);
		enabled = crtc;
	} else
		planea_wm = fifo_size - wm_info->guard_size;

	fifo_size = dev_priv->display.get_fifo_size(dev, 1);
	crtc = intel_get_crtc_for_plane(dev, 1);
	if (crtc->enabled && crtc->fb) {
		planeb_wm = intel_calculate_wm(crtc->mode.clock,
					       wm_info, fifo_size,
					       crtc->fb->bits_per_pixel / 8,
					       latency_ns);
		if (enabled == NULL)
			enabled = crtc;
		else
			enabled = NULL;
	} else
		planeb_wm = fifo_size - wm_info->guard_size;

	DRM_DEBUG_KMS("FIFO watermarks - A: %d, B: %d\n", planea_wm, planeb_wm);

	/*
	 * Overlay gets an aggressive default since video jitter is bad.
	 */
	cwm = 2;

	/* Play safe and disable self-refresh before adjusting watermarks. */
	if (IS_I945G(dev) || IS_I945GM(dev))
		I915_WRITE(FW_BLC_SELF, FW_BLC_SELF_EN_MASK | 0);
	else if (IS_I915GM(dev))
		I915_WRITE(INSTPM, I915_READ(INSTPM) & ~INSTPM_SELF_EN);

	/* Calc sr entries for one plane configs */
	if (HAS_FW_BLC(dev) && enabled) {
		/* self-refresh has much higher latency */
		static const int sr_latency_ns = 6000;
		int clock = enabled->mode.clock;
		int htotal = enabled->mode.htotal;
		int hdisplay = enabled->mode.hdisplay;
		int pixel_size = enabled->fb->bits_per_pixel / 8;
		unsigned long line_time_us;
		int entries;

		line_time_us = (htotal * 1000) / clock;

		/* Use ns/us then divide to preserve precision */
		entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) *
			pixel_size * hdisplay;
		entries = DIV_ROUND_UP(entries, wm_info->cacheline_size);
		DRM_DEBUG_KMS("self-refresh entries: %d\n", entries);
		srwm = wm_info->fifo_size - entries;
		if (srwm < 0)
			srwm = 1;

		if (IS_I945G(dev) || IS_I945GM(dev))
			I915_WRITE(FW_BLC_SELF,
				   FW_BLC_SELF_FIFO_MASK | (srwm & 0xff));
		else if (IS_I915GM(dev))
			I915_WRITE(FW_BLC_SELF, srwm & 0x3f);
	}

	DRM_DEBUG_KMS("Setting FIFO watermarks - A: %d, B: %d, C: %d, SR %d\n",
		      planea_wm, planeb_wm, cwm, srwm);

	fwater_lo = ((planeb_wm & 0x3f) << 16) | (planea_wm & 0x3f);
	fwater_hi = (cwm & 0x1f);

	/* Set request length to 8 cachelines per fetch */
	fwater_lo = fwater_lo | (1 << 24) | (1 << 8);
	fwater_hi = fwater_hi | (1 << 8);

	I915_WRITE(FW_BLC, fwater_lo);
	I915_WRITE(FW_BLC2, fwater_hi);

	if (HAS_FW_BLC(dev)) {
		if (enabled) {
			if (IS_I945G(dev) || IS_I945GM(dev))
				I915_WRITE(FW_BLC_SELF,
					   FW_BLC_SELF_EN_MASK | FW_BLC_SELF_EN);
			else if (IS_I915GM(dev))
				I915_WRITE(INSTPM, I915_READ(INSTPM) | INSTPM_SELF_EN);
			DRM_DEBUG_KMS("memory self refresh enabled\n");
		} else
			DRM_DEBUG_KMS("memory self refresh disabled\n");
	}
}

static void i830_update_wm(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_crtc *crtc;
	uint32_t fwater_lo;
	int planea_wm;

	crtc = single_enabled_crtc(dev);
	if (crtc == NULL)
		return;

	planea_wm = intel_calculate_wm(crtc->mode.clock, &i830_wm_info,
				       dev_priv->display.get_fifo_size(dev, 0),
				       crtc->fb->bits_per_pixel / 8,
				       latency_ns);
	fwater_lo = I915_READ(FW_BLC) & ~0xfff;
	fwater_lo |= (3<<8) | planea_wm;

	DRM_DEBUG_KMS("Setting FIFO watermarks - A: %d\n", planea_wm);

	I915_WRITE(FW_BLC, fwater_lo);
}

#define ILK_LP0_PLANE_LATENCY		700
#define ILK_LP0_CURSOR_LATENCY		1300

/*
 * Check the wm result.
 *
 * If any calculated watermark values is larger than the maximum value that
 * can be programmed into the associated watermark register, that watermark
 * must be disabled.
 */
static bool ironlake_check_srwm(struct drm_device *dev, int level,
				int fbc_wm, int display_wm, int cursor_wm,
				const struct intel_watermark_params *display,
				const struct intel_watermark_params *cursor)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	DRM_DEBUG_KMS("watermark %d: display plane %d, fbc lines %d,"
		      " cursor %d\n", level, display_wm, fbc_wm, cursor_wm);

	if (fbc_wm > SNB_FBC_MAX_SRWM) {
		DRM_DEBUG_KMS("fbc watermark(%d) is too large(%d), disabling wm%d+\n",
			      fbc_wm, SNB_FBC_MAX_SRWM, level);

		/* fbc has it's own way to disable FBC WM */
		I915_WRITE(DISP_ARB_CTL,
			   I915_READ(DISP_ARB_CTL) | DISP_FBC_WM_DIS);
		return false;
	}

	if (display_wm > display->max_wm) {
		DRM_DEBUG_KMS("display watermark(%d) is too large(%d), disabling wm%d+\n",
			      display_wm, SNB_DISPLAY_MAX_SRWM, level);
		return false;
	}

	if (cursor_wm > cursor->max_wm) {
		DRM_DEBUG_KMS("cursor watermark(%d) is too large(%d), disabling wm%d+\n",
			      cursor_wm, SNB_CURSOR_MAX_SRWM, level);
		return false;
	}

	if (!(fbc_wm || display_wm || cursor_wm)) {
		DRM_DEBUG_KMS("latency %d is 0, disabling wm%d+\n", level, level);
		return false;
	}

	return true;
}

/*
 * Compute watermark values of WM[1-3],
 */
static bool ironlake_compute_srwm(struct drm_device *dev, int level, int plane,
				  int latency_ns,
				  const struct intel_watermark_params *display,
				  const struct intel_watermark_params *cursor,
				  int *fbc_wm, int *display_wm, int *cursor_wm)
{
	struct drm_crtc *crtc;
	unsigned long line_time_us;
	int hdisplay, htotal, pixel_size, clock;
	int line_count, line_size;
	int small, large;
	int entries;

	if (!latency_ns) {
		*fbc_wm = *display_wm = *cursor_wm = 0;
		return false;
	}

	crtc = intel_get_crtc_for_plane(dev, plane);
	hdisplay = crtc->mode.hdisplay;
	htotal = crtc->mode.htotal;
	clock = crtc->mode.clock;
	pixel_size = crtc->fb->bits_per_pixel / 8;

	line_time_us = (htotal * 1000) / clock;
	line_count = (latency_ns / line_time_us + 1000) / 1000;
	line_size = hdisplay * pixel_size;

	/* Use the minimum of the small and large buffer method for primary */
	small = ((clock * pixel_size / 1000) * latency_ns) / 1000;
	large = line_count * line_size;

	entries = DIV_ROUND_UP(min(small, large), display->cacheline_size);
	*display_wm = entries + display->guard_size;

	/*
	 * Spec says:
	 * FBC WM = ((Final Primary WM * 64) / number of bytes per line) + 2
	 */
	*fbc_wm = DIV_ROUND_UP(*display_wm * 64, line_size) + 2;

	/* calculate the self-refresh watermark for display cursor */
	entries = line_count * pixel_size * 64;
	entries = DIV_ROUND_UP(entries, cursor->cacheline_size);
	*cursor_wm = entries + cursor->guard_size;

	return ironlake_check_srwm(dev, level,
				   *fbc_wm, *display_wm, *cursor_wm,
				   display, cursor);
}

static void ironlake_update_wm(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int fbc_wm, plane_wm, cursor_wm;
	unsigned int enabled;

	enabled = 0;
	if (g4x_compute_wm0(dev, 0,
			    &ironlake_display_wm_info,
			    ILK_LP0_PLANE_LATENCY,
			    &ironlake_cursor_wm_info,
			    ILK_LP0_CURSOR_LATENCY,
			    &plane_wm, &cursor_wm)) {
		I915_WRITE(WM0_PIPEA_ILK,
			   (plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm);
		DRM_DEBUG_KMS("FIFO watermarks For pipe A -"
			      " plane %d, " "cursor: %d\n",
			      plane_wm, cursor_wm);
		enabled |= 1;
	}

	if (g4x_compute_wm0(dev, 1,
			    &ironlake_display_wm_info,
			    ILK_LP0_PLANE_LATENCY,
			    &ironlake_cursor_wm_info,
			    ILK_LP0_CURSOR_LATENCY,
			    &plane_wm, &cursor_wm)) {
		I915_WRITE(WM0_PIPEB_ILK,
			   (plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm);
		DRM_DEBUG_KMS("FIFO watermarks For pipe B -"
			      " plane %d, cursor: %d\n",
			      plane_wm, cursor_wm);
		enabled |= 2;
	}

	/*
	 * Calculate and update the self-refresh watermark only when one
	 * display plane is used.
	 */
	I915_WRITE(WM3_LP_ILK, 0);
	I915_WRITE(WM2_LP_ILK, 0);
	I915_WRITE(WM1_LP_ILK, 0);

	if (!single_plane_enabled(enabled))
		return;
	enabled = ffs(enabled) - 1;

	/* WM1 */
	if (!ironlake_compute_srwm(dev, 1, enabled,
				   ILK_READ_WM1_LATENCY() * 500,
				   &ironlake_display_srwm_info,
				   &ironlake_cursor_srwm_info,
				   &fbc_wm, &plane_wm, &cursor_wm))
		return;

	I915_WRITE(WM1_LP_ILK,
		   WM1_LP_SR_EN |
		   (ILK_READ_WM1_LATENCY() << WM1_LP_LATENCY_SHIFT) |
		   (fbc_wm << WM1_LP_FBC_SHIFT) |
		   (plane_wm << WM1_LP_SR_SHIFT) |
		   cursor_wm);

	/* WM2 */
	if (!ironlake_compute_srwm(dev, 2, enabled,
				   ILK_READ_WM2_LATENCY() * 500,
				   &ironlake_display_srwm_info,
				   &ironlake_cursor_srwm_info,
				   &fbc_wm, &plane_wm, &cursor_wm))
		return;

	I915_WRITE(WM2_LP_ILK,
		   WM2_LP_EN |
		   (ILK_READ_WM2_LATENCY() << WM1_LP_LATENCY_SHIFT) |
		   (fbc_wm << WM1_LP_FBC_SHIFT) |
		   (plane_wm << WM1_LP_SR_SHIFT) |
		   cursor_wm);

	/*
	 * WM3 is unsupported on ILK, probably because we don't have latency
	 * data for that power state
	 */
}

static void sandybridge_update_wm(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int latency = SNB_READ_WM0_LATENCY() * 100;	/* In unit 0.1us */
	u32 val;
	int fbc_wm, plane_wm, cursor_wm;
	unsigned int enabled;

	enabled = 0;
	if (g4x_compute_wm0(dev, 0,
			    &sandybridge_display_wm_info, latency,
			    &sandybridge_cursor_wm_info, latency,
			    &plane_wm, &cursor_wm)) {
		val = I915_READ(WM0_PIPEA_ILK);
		val &= ~(WM0_PIPE_PLANE_MASK | WM0_PIPE_CURSOR_MASK);
		I915_WRITE(WM0_PIPEA_ILK, val |
			   ((plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm));
		DRM_DEBUG_KMS("FIFO watermarks For pipe A -"
			      " plane %d, " "cursor: %d\n",
			      plane_wm, cursor_wm);
		enabled |= 1;
	}

	if (g4x_compute_wm0(dev, 1,
			    &sandybridge_display_wm_info, latency,
			    &sandybridge_cursor_wm_info, latency,
			    &plane_wm, &cursor_wm)) {
		val = I915_READ(WM0_PIPEB_ILK);
		val &= ~(WM0_PIPE_PLANE_MASK | WM0_PIPE_CURSOR_MASK);
		I915_WRITE(WM0_PIPEB_ILK, val |
			   ((plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm));
		DRM_DEBUG_KMS("FIFO watermarks For pipe B -"
			      " plane %d, cursor: %d\n",
			      plane_wm, cursor_wm);
		enabled |= 2;
	}

	if ((dev_priv->num_pipe == 3) &&
	    g4x_compute_wm0(dev, 2,
			    &sandybridge_display_wm_info, latency,
			    &sandybridge_cursor_wm_info, latency,
			    &plane_wm, &cursor_wm)) {
		val = I915_READ(WM0_PIPEC_IVB);
		val &= ~(WM0_PIPE_PLANE_MASK | WM0_PIPE_CURSOR_MASK);
		I915_WRITE(WM0_PIPEC_IVB, val |
			   ((plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm));
		DRM_DEBUG_KMS("FIFO watermarks For pipe C -"
			      " plane %d, cursor: %d\n",
			      plane_wm, cursor_wm);
		enabled |= 3;
	}

	/*
	 * Calculate and update the self-refresh watermark only when one
	 * display plane is used.
	 *
	 * SNB support 3 levels of watermark.
	 *
	 * WM1/WM2/WM2 watermarks have to be enabled in the ascending order,
	 * and disabled in the descending order
	 *
	 */
	I915_WRITE(WM3_LP_ILK, 0);
	I915_WRITE(WM2_LP_ILK, 0);
	I915_WRITE(WM1_LP_ILK, 0);

	if (!single_plane_enabled(enabled) ||
	    dev_priv->sprite_scaling_enabled)
		return;
	enabled = ffs(enabled) - 1;

	/* WM1 */
	if (!ironlake_compute_srwm(dev, 1, enabled,
				   SNB_READ_WM1_LATENCY() * 500,
				   &sandybridge_display_srwm_info,
				   &sandybridge_cursor_srwm_info,
				   &fbc_wm, &plane_wm, &cursor_wm))
		return;

	I915_WRITE(WM1_LP_ILK,
		   WM1_LP_SR_EN |
		   (SNB_READ_WM1_LATENCY() << WM1_LP_LATENCY_SHIFT) |
		   (fbc_wm << WM1_LP_FBC_SHIFT) |
		   (plane_wm << WM1_LP_SR_SHIFT) |
		   cursor_wm);

	/* WM2 */
	if (!ironlake_compute_srwm(dev, 2, enabled,
				   SNB_READ_WM2_LATENCY() * 500,
				   &sandybridge_display_srwm_info,
				   &sandybridge_cursor_srwm_info,
				   &fbc_wm, &plane_wm, &cursor_wm))
		return;

	I915_WRITE(WM2_LP_ILK,
		   WM2_LP_EN |
		   (SNB_READ_WM2_LATENCY() << WM1_LP_LATENCY_SHIFT) |
		   (fbc_wm << WM1_LP_FBC_SHIFT) |
		   (plane_wm << WM1_LP_SR_SHIFT) |
		   cursor_wm);

	/* WM3 */
	if (!ironlake_compute_srwm(dev, 3, enabled,
				   SNB_READ_WM3_LATENCY() * 500,
				   &sandybridge_display_srwm_info,
				   &sandybridge_cursor_srwm_info,
				   &fbc_wm, &plane_wm, &cursor_wm))
		return;

	I915_WRITE(WM3_LP_ILK,
		   WM3_LP_EN |
		   (SNB_READ_WM3_LATENCY() << WM1_LP_LATENCY_SHIFT) |
		   (fbc_wm << WM1_LP_FBC_SHIFT) |
		   (plane_wm << WM1_LP_SR_SHIFT) |
		   cursor_wm);
}

static void
haswell_update_linetime_wm(struct drm_device *dev, int pipe,
				 struct drm_display_mode *mode)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 temp;

	temp = I915_READ(PIPE_WM_LINETIME(pipe));
	temp &= ~PIPE_WM_LINETIME_MASK;

	/* The WM are computed with base on how long it takes to fill a single
	 * row at the given clock rate, multiplied by 8.
	 * */
	temp |= PIPE_WM_LINETIME_TIME(
		((mode->crtc_hdisplay * 1000) / mode->clock) * 8);

	/* IPS watermarks are only used by pipe A, and are ignored by
	 * pipes B and C.  They are calculated similarly to the common
	 * linetime values, except that we are using CD clock frequency
	 * in MHz instead of pixel rate for the division.
	 *
	 * This is a placeholder for the IPS watermark calculation code.
	 */

	I915_WRITE(PIPE_WM_LINETIME(pipe), temp);
}

static bool
sandybridge_compute_sprite_wm(struct drm_device *dev, int plane,
			      uint32_t sprite_width, int pixel_size,
			      const struct intel_watermark_params *display,
			      int display_latency_ns, int *sprite_wm)
{
	struct drm_crtc *crtc;
	int clock;
	int entries, tlb_miss;

	crtc = intel_get_crtc_for_plane(dev, plane);
	if (crtc->fb == NULL || !crtc->enabled) {
		*sprite_wm = display->guard_size;
		return false;
	}

	clock = crtc->mode.clock;

	/* Use the small buffer method to calculate the sprite watermark */
	entries = ((clock * pixel_size / 1000) * display_latency_ns) / 1000;
	tlb_miss = display->fifo_size*display->cacheline_size -
		sprite_width * 8;
	if (tlb_miss > 0)
		entries += tlb_miss;
	entries = DIV_ROUND_UP(entries, display->cacheline_size);
	*sprite_wm = entries + display->guard_size;
	if (*sprite_wm > (int)display->max_wm)
		*sprite_wm = display->max_wm;

	return true;
}

static bool
sandybridge_compute_sprite_srwm(struct drm_device *dev, int plane,
				uint32_t sprite_width, int pixel_size,
				const struct intel_watermark_params *display,
				int latency_ns, int *sprite_wm)
{
	struct drm_crtc *crtc;
	unsigned long line_time_us;
	int clock;
	int line_count, line_size;
	int small, large;
	int entries;

	if (!latency_ns) {
		*sprite_wm = 0;
		return false;
	}

	crtc = intel_get_crtc_for_plane(dev, plane);
	clock = crtc->mode.clock;
	if (!clock) {
		*sprite_wm = 0;
		return false;
	}

	line_time_us = (sprite_width * 1000) / clock;
	if (!line_time_us) {
		*sprite_wm = 0;
		return false;
	}

	line_count = (latency_ns / line_time_us + 1000) / 1000;
	line_size = sprite_width * pixel_size;

	/* Use the minimum of the small and large buffer method for primary */
	small = ((clock * pixel_size / 1000) * latency_ns) / 1000;
	large = line_count * line_size;

	entries = DIV_ROUND_UP(min(small, large), display->cacheline_size);
	*sprite_wm = entries + display->guard_size;

	return *sprite_wm > 0x3ff ? false : true;
}

static void sandybridge_update_sprite_wm(struct drm_device *dev, int pipe,
					 uint32_t sprite_width, int pixel_size)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int latency = SNB_READ_WM0_LATENCY() * 100;	/* In unit 0.1us */
	u32 val;
	int sprite_wm, reg;
	int ret;

	switch (pipe) {
	case 0:
		reg = WM0_PIPEA_ILK;
		break;
	case 1:
		reg = WM0_PIPEB_ILK;
		break;
	case 2:
		reg = WM0_PIPEC_IVB;
		break;
	default:
		return; /* bad pipe */
	}

	ret = sandybridge_compute_sprite_wm(dev, pipe, sprite_width, pixel_size,
					    &sandybridge_display_wm_info,
					    latency, &sprite_wm);
	if (!ret) {
		DRM_DEBUG_KMS("failed to compute sprite wm for pipe %d\n",
			      pipe);
		return;
	}

	val = I915_READ(reg);
	val &= ~WM0_PIPE_SPRITE_MASK;
	I915_WRITE(reg, val | (sprite_wm << WM0_PIPE_SPRITE_SHIFT));
	DRM_DEBUG_KMS("sprite watermarks For pipe %d - %d\n", pipe, sprite_wm);


	ret = sandybridge_compute_sprite_srwm(dev, pipe, sprite_width,
					      pixel_size,
					      &sandybridge_display_srwm_info,
					      SNB_READ_WM1_LATENCY() * 500,
					      &sprite_wm);
	if (!ret) {
		DRM_DEBUG_KMS("failed to compute sprite lp1 wm on pipe %d\n",
			      pipe);
		return;
	}
	I915_WRITE(WM1S_LP_ILK, sprite_wm);

	/* Only IVB has two more LP watermarks for sprite */
	if (!IS_IVYBRIDGE(dev))
		return;

	ret = sandybridge_compute_sprite_srwm(dev, pipe, sprite_width,
					      pixel_size,
					      &sandybridge_display_srwm_info,
					      SNB_READ_WM2_LATENCY() * 500,
					      &sprite_wm);
	if (!ret) {
		DRM_DEBUG_KMS("failed to compute sprite lp2 wm on pipe %d\n",
			      pipe);
		return;
	}
	I915_WRITE(WM2S_LP_IVB, sprite_wm);

	ret = sandybridge_compute_sprite_srwm(dev, pipe, sprite_width,
					      pixel_size,
					      &sandybridge_display_srwm_info,
					      SNB_READ_WM3_LATENCY() * 500,
					      &sprite_wm);
	if (!ret) {
		DRM_DEBUG_KMS("failed to compute sprite lp3 wm on pipe %d\n",
			      pipe);
		return;
	}
	I915_WRITE(WM3S_LP_IVB, sprite_wm);
}

/**
 * intel_update_watermarks - update FIFO watermark values based on current modes
 *
 * Calculate watermark values for the various WM regs based on current mode
 * and plane configuration.
 *
 * There are several cases to deal with here:
 *   - normal (i.e. non-self-refresh)
 *   - self-refresh (SR) mode
 *   - lines are large relative to FIFO size (buffer can hold up to 2)
 *   - lines are small relative to FIFO size (buffer can hold more than 2
 *     lines), so need to account for TLB latency
 *
 *   The normal calculation is:
 *     watermark = dotclock * bytes per pixel * latency
 *   where latency is platform & configuration dependent (we assume pessimal
 *   values here).
 *
 *   The SR calculation is:
 *     watermark = (trunc(latency/line time)+1) * surface width *
 *       bytes per pixel
 *   where
 *     line time = htotal / dotclock
 *     surface width = hdisplay for normal plane and 64 for cursor
 *   and latency is assumed to be high, as above.
 *
 * The final value programmed to the register should always be rounded up,
 * and include an extra 2 entries to account for clock crossings.
 *
 * We don't use the sprite, so we can ignore that.  And on Crestline we have
 * to set the non-SR watermarks to 8.
 */
void intel_update_watermarks(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (dev_priv->display.update_wm)
		dev_priv->display.update_wm(dev);
}

void intel_update_linetime_watermarks(struct drm_device *dev,
		int pipe, struct drm_display_mode *mode)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (dev_priv->display.update_linetime_wm)
		dev_priv->display.update_linetime_wm(dev, pipe, mode);
}

void intel_update_sprite_watermarks(struct drm_device *dev, int pipe,
				    uint32_t sprite_width, int pixel_size)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (dev_priv->display.update_sprite_wm)
		dev_priv->display.update_sprite_wm(dev, pipe, sprite_width,
						   pixel_size);
}

static struct drm_i915_gem_object *
intel_alloc_context_page(struct drm_device *dev)
{
	struct drm_i915_gem_object *ctx;
	int ret;

	WARN_ON(!mutex_is_locked(&dev->struct_mutex));

	ctx = i915_gem_alloc_object(dev, 4096);
	if (!ctx) {
		DRM_DEBUG("failed to alloc power context, RC6 disabled\n");
		return NULL;
	}

	ret = i915_gem_object_pin(ctx, 4096, true);
	if (ret) {
		DRM_ERROR("failed to pin power context: %d\n", ret);
		goto err_unref;
	}

	ret = i915_gem_object_set_to_gtt_domain(ctx, 1);
	if (ret) {
		DRM_ERROR("failed to set-domain on power context: %d\n", ret);
		goto err_unpin;
	}

	return ctx;

err_unpin:
	i915_gem_object_unpin(ctx);
err_unref:
	drm_gem_object_unreference(&ctx->base);
	mutex_unlock(&dev->struct_mutex);
	return NULL;
}

bool ironlake_set_drps(struct drm_device *dev, u8 val)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u16 rgvswctl;

	rgvswctl = I915_READ16(MEMSWCTL);
	if (rgvswctl & MEMCTL_CMD_STS) {
		DRM_DEBUG("gpu busy, RCS change rejected\n");
		return false; /* still busy with another command */
	}

	rgvswctl = (MEMCTL_CMD_CHFREQ << MEMCTL_CMD_SHIFT) |
		(val << MEMCTL_FREQ_SHIFT) | MEMCTL_SFCAVM;
	I915_WRITE16(MEMSWCTL, rgvswctl);
	POSTING_READ16(MEMSWCTL);

	rgvswctl |= MEMCTL_CMD_STS;
	I915_WRITE16(MEMSWCTL, rgvswctl);

	return true;
}

static void ironlake_enable_drps(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 rgvmodectl = I915_READ(MEMMODECTL);
	u8 fmax, fmin, fstart, vstart;

	/* Enable temp reporting */
	I915_WRITE16(PMMISC, I915_READ(PMMISC) | MCPPCE_EN);
	I915_WRITE16(TSC1, I915_READ(TSC1) | TSE);

	/* 100ms RC evaluation intervals */
	I915_WRITE(RCUPEI, 100000);
	I915_WRITE(RCDNEI, 100000);

	/* Set max/min thresholds to 90ms and 80ms respectively */
	I915_WRITE(RCBMAXAVG, 90000);
	I915_WRITE(RCBMINAVG, 80000);

	I915_WRITE(MEMIHYST, 1);

	/* Set up min, max, and cur for interrupt handling */
	fmax = (rgvmodectl & MEMMODE_FMAX_MASK) >> MEMMODE_FMAX_SHIFT;
	fmin = (rgvmodectl & MEMMODE_FMIN_MASK);
	fstart = (rgvmodectl & MEMMODE_FSTART_MASK) >>
		MEMMODE_FSTART_SHIFT;

	vstart = (I915_READ(PXVFREQ_BASE + (fstart * 4)) & PXVFREQ_PX_MASK) >>
		PXVFREQ_PX_SHIFT;

	dev_priv->fmax = fmax; /* IPS callback will increase this */
	dev_priv->fstart = fstart;

	dev_priv->max_delay = fstart;
	dev_priv->min_delay = fmin;
	dev_priv->cur_delay = fstart;

	DRM_DEBUG_DRIVER("fmax: %d, fmin: %d, fstart: %d\n",
			 fmax, fmin, fstart);

	I915_WRITE(MEMINTREN, MEMINT_CX_SUPR_EN | MEMINT_EVAL_CHG_EN);

	/*
	 * Interrupts will be enabled in ironlake_irq_postinstall
	 */

	I915_WRITE(VIDSTART, vstart);
	POSTING_READ(VIDSTART);

	rgvmodectl |= MEMMODE_SWMODE_EN;
	I915_WRITE(MEMMODECTL, rgvmodectl);

	if (wait_for((I915_READ(MEMSWCTL) & MEMCTL_CMD_STS) == 0, 10))
		DRM_ERROR("stuck trying to change perf mode\n");
	msleep(1);

	ironlake_set_drps(dev, fstart);

	dev_priv->last_count1 = I915_READ(0x112e4) + I915_READ(0x112e8) +
		I915_READ(0x112e0);
	dev_priv->last_time1 = jiffies_to_msecs(jiffies);
	dev_priv->last_count2 = I915_READ(0x112f4);
	getrawmonotonic(&dev_priv->last_time2);
}

static void ironlake_disable_drps(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u16 rgvswctl = I915_READ16(MEMSWCTL);

	/* Ack interrupts, disable EFC interrupt */
	I915_WRITE(MEMINTREN, I915_READ(MEMINTREN) & ~MEMINT_EVAL_CHG_EN);
	I915_WRITE(MEMINTRSTS, MEMINT_EVAL_CHG);
	I915_WRITE(DEIER, I915_READ(DEIER) & ~DE_PCU_EVENT);
	I915_WRITE(DEIIR, DE_PCU_EVENT);
	I915_WRITE(DEIMR, I915_READ(DEIMR) | DE_PCU_EVENT);

	/* Go back to the starting frequency */
	ironlake_set_drps(dev, dev_priv->fstart);
	msleep(1);
	rgvswctl |= MEMCTL_CMD_STS;
	I915_WRITE(MEMSWCTL, rgvswctl);
	msleep(1);

}

void gen6_set_rps(struct drm_device *dev, u8 val)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 limits;

	limits = 0;
	if (val >= dev_priv->max_delay)
		val = dev_priv->max_delay;
	else
		limits |= dev_priv->max_delay << 24;

	if (val <= dev_priv->min_delay)
		val = dev_priv->min_delay;
	else
		limits |= dev_priv->min_delay << 16;

	if (val == dev_priv->cur_delay)
		return;

	I915_WRITE(GEN6_RPNSWREQ,
		   GEN6_FREQUENCY(val) |
		   GEN6_OFFSET(0) |
		   GEN6_AGGRESSIVE_TURBO);

	/* Make sure we continue to get interrupts
	 * until we hit the minimum or maximum frequencies.
	 */
	I915_WRITE(GEN6_RP_INTERRUPT_LIMITS, limits);

	dev_priv->cur_delay = val;
}

static void gen6_disable_rps(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	I915_WRITE(GEN6_RC_CONTROL, 0);
	I915_WRITE(GEN6_RPNSWREQ, 1 << 31);
	I915_WRITE(GEN6_PMINTRMSK, 0xffffffff);
	I915_WRITE(GEN6_PMIER, 0);
	/* Complete PM interrupt masking here doesn't race with the rps work
	 * item again unmasking PM interrupts because that is using a different
	 * register (PMIMR) to mask PM interrupts. The only risk is in leaving
	 * stale bits in PMIIR and PMIMR which gen6_enable_rps will clean up. */

	spin_lock_irq(&dev_priv->rps_lock);
	dev_priv->pm_iir = 0;
	spin_unlock_irq(&dev_priv->rps_lock);

	I915_WRITE(GEN6_PMIIR, I915_READ(GEN6_PMIIR));
}

int intel_enable_rc6(const struct drm_device *dev)
{
	/*
	 * Respect the kernel parameter if it is set
	 */
	if (i915_enable_rc6 >= 0)
		return i915_enable_rc6;

	/*
	 * Disable RC6 on Ironlake
	 */
	if (INTEL_INFO(dev)->gen == 5)
		return 0;

	/* On Haswell, only RC6 is available. So let's enable it by default to
	 * provide better testing and coverage since the beginning.
	 */
	if (IS_HASWELL(dev))
		return INTEL_RC6_ENABLE;

	/*
	 * Disable rc6 on Sandybridge
	 */
	if (INTEL_INFO(dev)->gen == 6) {
		DRM_DEBUG_DRIVER("Sandybridge: deep RC6 disabled\n");
		return INTEL_RC6_ENABLE;
	}
	DRM_DEBUG_DRIVER("RC6 and deep RC6 enabled\n");
	return (INTEL_RC6_ENABLE | INTEL_RC6p_ENABLE);
}

static void gen6_enable_rps(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_ring_buffer *ring;
	u32 rp_state_cap;
	u32 gt_perf_status;
	u32 pcu_mbox, rc6_mask = 0;
	u32 gtfifodbg;
	int rc6_mode;
	int i;

	WARN_ON(!mutex_is_locked(&dev->struct_mutex));

	/* Here begins a magic sequence of register writes to enable
	 * auto-downclocking.
	 *
	 * Perhaps there might be some value in exposing these to
	 * userspace...
	 */
	I915_WRITE(GEN6_RC_STATE, 0);

	/* Clear the DBG now so we don't confuse earlier errors */
	if ((gtfifodbg = I915_READ(GTFIFODBG))) {
		DRM_ERROR("GT fifo had a previous error %x\n", gtfifodbg);
		I915_WRITE(GTFIFODBG, gtfifodbg);
	}

	gen6_gt_force_wake_get(dev_priv);

	rp_state_cap = I915_READ(GEN6_RP_STATE_CAP);
	gt_perf_status = I915_READ(GEN6_GT_PERF_STATUS);

	/* In units of 100MHz */
	dev_priv->max_delay = rp_state_cap & 0xff;
	dev_priv->min_delay = (rp_state_cap & 0xff0000) >> 16;
	dev_priv->cur_delay = 0;

	/* disable the counters and set deterministic thresholds */
	I915_WRITE(GEN6_RC_CONTROL, 0);

	I915_WRITE(GEN6_RC1_WAKE_RATE_LIMIT, 1000 << 16);
	I915_WRITE(GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16 | 30);
	I915_WRITE(GEN6_RC6pp_WAKE_RATE_LIMIT, 30);
	I915_WRITE(GEN6_RC_EVALUATION_INTERVAL, 125000);
	I915_WRITE(GEN6_RC_IDLE_HYSTERSIS, 25);

	for_each_ring(ring, dev_priv, i)
		I915_WRITE(RING_MAX_IDLE(ring->mmio_base), 10);

	I915_WRITE(GEN6_RC_SLEEP, 0);
	I915_WRITE(GEN6_RC1e_THRESHOLD, 1000);
	I915_WRITE(GEN6_RC6_THRESHOLD, 50000);
	I915_WRITE(GEN6_RC6p_THRESHOLD, 100000);
	I915_WRITE(GEN6_RC6pp_THRESHOLD, 64000); /* unused */

	/* Check if we are enabling RC6 */
	rc6_mode = intel_enable_rc6(dev_priv->dev);
	if (rc6_mode & INTEL_RC6_ENABLE)
		rc6_mask |= GEN6_RC_CTL_RC6_ENABLE;

	/* We don't use those on Haswell */
	if (!IS_HASWELL(dev)) {
		if (rc6_mode & INTEL_RC6p_ENABLE)
			rc6_mask |= GEN6_RC_CTL_RC6p_ENABLE;

		if (rc6_mode & INTEL_RC6pp_ENABLE)
			rc6_mask |= GEN6_RC_CTL_RC6pp_ENABLE;
	}

	DRM_INFO("Enabling RC6 states: RC6 %s, RC6p %s, RC6pp %s\n",
			(rc6_mask & GEN6_RC_CTL_RC6_ENABLE) ? "on" : "off",
			(rc6_mask & GEN6_RC_CTL_RC6p_ENABLE) ? "on" : "off",
			(rc6_mask & GEN6_RC_CTL_RC6pp_ENABLE) ? "on" : "off");

	I915_WRITE(GEN6_RC_CONTROL,
		   rc6_mask |
		   GEN6_RC_CTL_EI_MODE(1) |
		   GEN6_RC_CTL_HW_ENABLE);

	I915_WRITE(GEN6_RPNSWREQ,
		   GEN6_FREQUENCY(10) |
		   GEN6_OFFSET(0) |
		   GEN6_AGGRESSIVE_TURBO);
	I915_WRITE(GEN6_RC_VIDEO_FREQ,
		   GEN6_FREQUENCY(12));

	I915_WRITE(GEN6_RP_DOWN_TIMEOUT, 1000000);
	I915_WRITE(GEN6_RP_INTERRUPT_LIMITS,
		   dev_priv->max_delay << 24 |
		   dev_priv->min_delay << 16);

	if (IS_HASWELL(dev)) {
		I915_WRITE(GEN6_RP_UP_THRESHOLD, 59400);
		I915_WRITE(GEN6_RP_DOWN_THRESHOLD, 245000);
		I915_WRITE(GEN6_RP_UP_EI, 66000);
		I915_WRITE(GEN6_RP_DOWN_EI, 350000);
	} else {
		I915_WRITE(GEN6_RP_UP_THRESHOLD, 10000);
		I915_WRITE(GEN6_RP_DOWN_THRESHOLD, 1000000);
		I915_WRITE(GEN6_RP_UP_EI, 100000);
		I915_WRITE(GEN6_RP_DOWN_EI, 5000000);
	}

	I915_WRITE(GEN6_RP_IDLE_HYSTERSIS, 10);
	I915_WRITE(GEN6_RP_CONTROL,
		   GEN6_RP_MEDIA_TURBO |
		   GEN6_RP_MEDIA_HW_NORMAL_MODE |
		   GEN6_RP_MEDIA_IS_GFX |
		   GEN6_RP_ENABLE |
		   GEN6_RP_UP_BUSY_AVG |
		   (IS_HASWELL(dev) ? GEN7_RP_DOWN_IDLE_AVG : GEN6_RP_DOWN_IDLE_CONT));

	if (wait_for((I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) == 0,
		     500))
		DRM_ERROR("timeout waiting for pcode mailbox to become idle\n");

	I915_WRITE(GEN6_PCODE_DATA, 0);
	I915_WRITE(GEN6_PCODE_MAILBOX,
		   GEN6_PCODE_READY |
		   GEN6_PCODE_WRITE_MIN_FREQ_TABLE);
	if (wait_for((I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) == 0,
		     500))
		DRM_ERROR("timeout waiting for pcode mailbox to finish\n");

	/* Check for overclock support */
	if (wait_for((I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) == 0,
		     500))
		DRM_ERROR("timeout waiting for pcode mailbox to become idle\n");
	I915_WRITE(GEN6_PCODE_MAILBOX, GEN6_READ_OC_PARAMS);
	pcu_mbox = I915_READ(GEN6_PCODE_DATA);
	if (wait_for((I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) == 0,
		     500))
		DRM_ERROR("timeout waiting for pcode mailbox to finish\n");
	if (pcu_mbox & (1<<31)) { /* OC supported */
		dev_priv->max_delay = pcu_mbox & 0xff;
		DRM_DEBUG_DRIVER("overclocking supported, adjusting frequency max to %dMHz\n", pcu_mbox * 50);
	}

	gen6_set_rps(dev_priv->dev, (gt_perf_status & 0xff00) >> 8);

	/* requires MSI enabled */
	I915_WRITE(GEN6_PMIER,
		   GEN6_PM_MBOX_EVENT |
		   GEN6_PM_THERMAL_EVENT |
		   GEN6_PM_RP_DOWN_TIMEOUT |
		   GEN6_PM_RP_UP_THRESHOLD |
		   GEN6_PM_RP_DOWN_THRESHOLD |
		   GEN6_PM_RP_UP_EI_EXPIRED |
		   GEN6_PM_RP_DOWN_EI_EXPIRED);
	spin_lock_irq(&dev_priv->rps_lock);
	WARN_ON(dev_priv->pm_iir != 0);
	I915_WRITE(GEN6_PMIMR, 0);
	spin_unlock_irq(&dev_priv->rps_lock);
	/* enable all PM interrupts */
	I915_WRITE(GEN6_PMINTRMSK, 0);

	gen6_gt_force_wake_put(dev_priv);
}

static void gen6_update_ring_freq(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int min_freq = 15;
	int gpu_freq, ia_freq, max_ia_freq;
	int scaling_factor = 180;

	WARN_ON(!mutex_is_locked(&dev->struct_mutex));

	max_ia_freq = cpufreq_quick_get_max(0);
	/*
	 * Default to measured freq if none found, PCU will ensure we don't go
	 * over
	 */
	if (!max_ia_freq)
		max_ia_freq = tsc_khz;

	/* Convert from kHz to MHz */
	max_ia_freq /= 1000;

	/*
	 * For each potential GPU frequency, load a ring frequency we'd like
	 * to use for memory access.  We do this by specifying the IA frequency
	 * the PCU should use as a reference to determine the ring frequency.
	 */
	for (gpu_freq = dev_priv->max_delay; gpu_freq >= dev_priv->min_delay;
	     gpu_freq--) {
		int diff = dev_priv->max_delay - gpu_freq;

		/*
		 * For GPU frequencies less than 750MHz, just use the lowest
		 * ring freq.
		 */
		if (gpu_freq < min_freq)
			ia_freq = 800;
		else
			ia_freq = max_ia_freq - ((diff * scaling_factor) / 2);
		ia_freq = DIV_ROUND_CLOSEST(ia_freq, 100);

		I915_WRITE(GEN6_PCODE_DATA,
			   (ia_freq << GEN6_PCODE_FREQ_IA_RATIO_SHIFT) |
			   gpu_freq);
		I915_WRITE(GEN6_PCODE_MAILBOX, GEN6_PCODE_READY |
			   GEN6_PCODE_WRITE_MIN_FREQ_TABLE);
		if (wait_for((I915_READ(GEN6_PCODE_MAILBOX) &
			      GEN6_PCODE_READY) == 0, 10)) {
			DRM_ERROR("pcode write of freq table timed out\n");
			continue;
		}
	}
}

static void ironlake_teardown_rc6(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (dev_priv->renderctx) {
		i915_gem_object_unpin(dev_priv->renderctx);
		drm_gem_object_unreference(&dev_priv->renderctx->base);
		dev_priv->renderctx = NULL;
	}

	if (dev_priv->pwrctx) {
		i915_gem_object_unpin(dev_priv->pwrctx);
		drm_gem_object_unreference(&dev_priv->pwrctx->base);
		dev_priv->pwrctx = NULL;
	}
}

void ironlake_disable_rc6(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (I915_READ(PWRCTXA)) {
		/* Wake the GPU, prevent RC6, then restore RSTDBYCTL */
		I915_WRITE(RSTDBYCTL, I915_READ(RSTDBYCTL) | RCX_SW_EXIT);
		wait_for(((I915_READ(RSTDBYCTL) & RSX_STATUS_MASK) == RSX_STATUS_ON),
			 50);

		I915_WRITE(PWRCTXA, 0);
		POSTING_READ(PWRCTXA);

		I915_WRITE(RSTDBYCTL, I915_READ(RSTDBYCTL) & ~RCX_SW_EXIT);
		POSTING_READ(RSTDBYCTL);
	}

	ironlake_teardown_rc6(dev);
}

static int ironlake_setup_rc6(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (dev_priv->renderctx == NULL)
		dev_priv->renderctx = intel_alloc_context_page(dev);
	if (!dev_priv->renderctx)
		return -ENOMEM;

	if (dev_priv->pwrctx == NULL)
		dev_priv->pwrctx = intel_alloc_context_page(dev);
	if (!dev_priv->pwrctx) {
		ironlake_teardown_rc6(dev);
		return -ENOMEM;
	}

	return 0;
}

void ironlake_enable_rc6(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_ring_buffer *ring = &dev_priv->ring[RCS];
	int ret;

	/* rc6 disabled by default due to repeated reports of hanging during
	 * boot and resume.
	 */
	if (!intel_enable_rc6(dev))
		return;

	WARN_ON(!mutex_is_locked(&dev->struct_mutex));

	ret = ironlake_setup_rc6(dev);
	if (ret)
		return;

	/*
	 * GPU can automatically power down the render unit if given a page
	 * to save state.
	 */
	ret = intel_ring_begin(ring, 6);
	if (ret) {
		ironlake_teardown_rc6(dev);
		return;
	}

	intel_ring_emit(ring, MI_SUSPEND_FLUSH | MI_SUSPEND_FLUSH_EN);
	intel_ring_emit(ring, MI_SET_CONTEXT);
	intel_ring_emit(ring, dev_priv->renderctx->gtt_offset |
			MI_MM_SPACE_GTT |
			MI_SAVE_EXT_STATE_EN |
			MI_RESTORE_EXT_STATE_EN |
			MI_RESTORE_INHIBIT);
	intel_ring_emit(ring, MI_SUSPEND_FLUSH);
	intel_ring_emit(ring, MI_NOOP);
	intel_ring_emit(ring, MI_FLUSH);
	intel_ring_advance(ring);

	/*
	 * Wait for the command parser to advance past MI_SET_CONTEXT. The HW
	 * does an implicit flush, combined with MI_FLUSH above, it should be
	 * safe to assume that renderctx is valid
	 */
	ret = intel_wait_ring_idle(ring);
	if (ret) {
		DRM_ERROR("failed to enable ironlake power power savings\n");
		ironlake_teardown_rc6(dev);
		return;
	}

	I915_WRITE(PWRCTXA, dev_priv->pwrctx->gtt_offset | PWRCTX_EN);
	I915_WRITE(RSTDBYCTL, I915_READ(RSTDBYCTL) & ~RCX_SW_EXIT);
}

static unsigned long intel_pxfreq(u32 vidfreq)
{
	unsigned long freq;
	int div = (vidfreq & 0x3f0000) >> 16;
	int post = (vidfreq & 0x3000) >> 12;
	int pre = (vidfreq & 0x7);

	if (!pre)
		return 0;

	freq = ((div * 133333) / ((1<<post) * pre));

	return freq;
}

static const struct cparams {
	u16 i;
	u16 t;
	u16 m;
	u16 c;
} cparams[] = {
	{ 1, 1333, 301, 28664 },
	{ 1, 1066, 294, 24460 },
	{ 1, 800, 294, 25192 },
	{ 0, 1333, 276, 27605 },
	{ 0, 1066, 276, 27605 },
	{ 0, 800, 231, 23784 },
};

unsigned long i915_chipset_val(struct drm_i915_private *dev_priv)
{
	u64 total_count, diff, ret;
	u32 count1, count2, count3, m = 0, c = 0;
	unsigned long now = jiffies_to_msecs(jiffies), diff1;
	int i;

	diff1 = now - dev_priv->last_time1;

	/* Prevent division-by-zero if we are asking too fast.
	 * Also, we don't get interesting results if we are polling
	 * faster than once in 10ms, so just return the saved value
	 * in such cases.
	 */
	if (diff1 <= 10)
		return dev_priv->chipset_power;

	count1 = I915_READ(DMIEC);
	count2 = I915_READ(DDREC);
	count3 = I915_READ(CSIEC);

	total_count = count1 + count2 + count3;

	/* FIXME: handle per-counter overflow */
	if (total_count < dev_priv->last_count1) {
		diff = ~0UL - dev_priv->last_count1;
		diff += total_count;
	} else {
		diff = total_count - dev_priv->last_count1;
	}

	for (i = 0; i < ARRAY_SIZE(cparams); i++) {
		if (cparams[i].i == dev_priv->c_m &&
		    cparams[i].t == dev_priv->r_t) {
			m = cparams[i].m;
			c = cparams[i].c;
			break;
		}
	}

	diff = div_u64(diff, diff1);
	ret = ((m * diff) + c);
	ret = div_u64(ret, 10);

	dev_priv->last_count1 = total_count;
	dev_priv->last_time1 = now;

	dev_priv->chipset_power = ret;

	return ret;
}

unsigned long i915_mch_val(struct drm_i915_private *dev_priv)
{
	unsigned long m, x, b;
	u32 tsfs;

	tsfs = I915_READ(TSFS);

	m = ((tsfs & TSFS_SLOPE_MASK) >> TSFS_SLOPE_SHIFT);
	x = I915_READ8(TR1);

	b = tsfs & TSFS_INTR_MASK;

	return ((m * x) / 127) - b;
}

static u16 pvid_to_extvid(struct drm_i915_private *dev_priv, u8 pxvid)
{
	static const struct v_table {
		u16 vd; /* in .1 mil */
		u16 vm; /* in .1 mil */
	} v_table[] = {
		{ 0, 0, },
		{ 375, 0, },
		{ 500, 0, },
		{ 625, 0, },
		{ 750, 0, },
		{ 875, 0, },
		{ 1000, 0, },
		{ 1125, 0, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4125, 3000, },
		{ 4250, 3125, },
		{ 4375, 3250, },
		{ 4500, 3375, },
		{ 4625, 3500, },
		{ 4750, 3625, },
		{ 4875, 3750, },
		{ 5000, 3875, },
		{ 5125, 4000, },
		{ 5250, 4125, },
		{ 5375, 4250, },
		{ 5500, 4375, },
		{ 5625, 4500, },
		{ 5750, 4625, },
		{ 5875, 4750, },
		{ 6000, 4875, },
		{ 6125, 5000, },
		{ 6250, 5125, },
		{ 6375, 5250, },
		{ 6500, 5375, },
		{ 6625, 5500, },
		{ 6750, 5625, },
		{ 6875, 5750, },
		{ 7000, 5875, },
		{ 7125, 6000, },
		{ 7250, 6125, },
		{ 7375, 6250, },
		{ 7500, 6375, },
		{ 7625, 6500, },
		{ 7750, 6625, },
		{ 7875, 6750, },
		{ 8000, 6875, },
		{ 8125, 7000, },
		{ 8250, 7125, },
		{ 8375, 7250, },
		{ 8500, 7375, },
		{ 8625, 7500, },
		{ 8750, 7625, },
		{ 8875, 7750, },
		{ 9000, 7875, },
		{ 9125, 8000, },
		{ 9250, 8125, },
		{ 9375, 8250, },
		{ 9500, 8375, },
		{ 9625, 8500, },
		{ 9750, 8625, },
		{ 9875, 8750, },
		{ 10000, 8875, },
		{ 10125, 9000, },
		{ 10250, 9125, },
		{ 10375, 9250, },
		{ 10500, 9375, },
		{ 10625, 9500, },
		{ 10750, 9625, },
		{ 10875, 9750, },
		{ 11000, 9875, },
		{ 11125, 10000, },
		{ 11250, 10125, },
		{ 11375, 10250, },
		{ 11500, 10375, },
		{ 11625, 10500, },
		{ 11750, 10625, },
		{ 11875, 10750, },
		{ 12000, 10875, },
		{ 12125, 11000, },
		{ 12250, 11125, },
		{ 12375, 11250, },
		{ 12500, 11375, },
		{ 12625, 11500, },
		{ 12750, 11625, },
		{ 12875, 11750, },
		{ 13000, 11875, },
		{ 13125, 12000, },
		{ 13250, 12125, },
		{ 13375, 12250, },
		{ 13500, 12375, },
		{ 13625, 12500, },
		{ 13750, 12625, },
		{ 13875, 12750, },
		{ 14000, 12875, },
		{ 14125, 13000, },
		{ 14250, 13125, },
		{ 14375, 13250, },
		{ 14500, 13375, },
		{ 14625, 13500, },
		{ 14750, 13625, },
		{ 14875, 13750, },
		{ 15000, 13875, },
		{ 15125, 14000, },
		{ 15250, 14125, },
		{ 15375, 14250, },
		{ 15500, 14375, },
		{ 15625, 14500, },
		{ 15750, 14625, },
		{ 15875, 14750, },
		{ 16000, 14875, },
		{ 16125, 15000, },
	};
	if (dev_priv->info->is_mobile)
		return v_table[pxvid].vm;
	else
		return v_table[pxvid].vd;
}

void i915_update_gfx_val(struct drm_i915_private *dev_priv)
{
	struct timespec now, diff1;
	u64 diff;
	unsigned long diffms;
	u32 count;

	if (dev_priv->info->gen != 5)
		return;

	getrawmonotonic(&now);
	diff1 = timespec_sub(now, dev_priv->last_time2);

	/* Don't divide by 0 */
	diffms = diff1.tv_sec * 1000 + diff1.tv_nsec / 1000000;
	if (!diffms)
		return;

	count = I915_READ(GFXEC);

	if (count < dev_priv->last_count2) {
		diff = ~0UL - dev_priv->last_count2;
		diff += count;
	} else {
		diff = count - dev_priv->last_count2;
	}

	dev_priv->last_count2 = count;
	dev_priv->last_time2 = now;

	/* More magic constants... */
	diff = diff * 1181;
	diff = div_u64(diff, diffms * 10);
	dev_priv->gfx_power = diff;
}

unsigned long i915_gfx_val(struct drm_i915_private *dev_priv)
{
	unsigned long t, corr, state1, corr2, state2;
	u32 pxvid, ext_v;

	pxvid = I915_READ(PXVFREQ_BASE + (dev_priv->cur_delay * 4));
	pxvid = (pxvid >> 24) & 0x7f;
	ext_v = pvid_to_extvid(dev_priv, pxvid);

	state1 = ext_v;

	t = i915_mch_val(dev_priv);

	/* Revel in the empirically derived constants */

	/* Correction factor in 1/100000 units */
	if (t > 80)
		corr = ((t * 2349) + 135940);
	else if (t >= 50)
		corr = ((t * 964) + 29317);
	else /* < 50 */
		corr = ((t * 301) + 1004);

	corr = corr * ((150142 * state1) / 10000 - 78642);
	corr /= 100000;
	corr2 = (corr * dev_priv->corr);

	state2 = (corr2 * state1) / 10000;
	state2 /= 100; /* convert to mW */

	i915_update_gfx_val(dev_priv);

	return dev_priv->gfx_power + state2;
}

/* Global for IPS driver to get at the current i915 device */
static struct drm_i915_private *i915_mch_dev;
/*
 * Lock protecting IPS related data structures
 *   - i915_mch_dev
 *   - dev_priv->max_delay
 *   - dev_priv->min_delay
 *   - dev_priv->fmax
 *   - dev_priv->gpu_busy
 */
static DEFINE_SPINLOCK(mchdev_lock);

/**
 * i915_read_mch_val - return value for IPS use
 *
 * Calculate and return a value for the IPS driver to use when deciding whether
 * we have thermal and power headroom to increase CPU or GPU power budget.
 */
unsigned long i915_read_mch_val(void)
{
	struct drm_i915_private *dev_priv;
	unsigned long chipset_val, graphics_val, ret = 0;

	spin_lock(&mchdev_lock);
	if (!i915_mch_dev)
		goto out_unlock;
	dev_priv = i915_mch_dev;

	chipset_val = i915_chipset_val(dev_priv);
	graphics_val = i915_gfx_val(dev_priv);

	ret = chipset_val + graphics_val;

out_unlock:
	spin_unlock(&mchdev_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(i915_read_mch_val);

/**
 * i915_gpu_raise - raise GPU frequency limit
 *
 * Raise the limit; IPS indicates we have thermal headroom.
 */
bool i915_gpu_raise(void)
{
	struct drm_i915_private *dev_priv;
	bool ret = true;

	spin_lock(&mchdev_lock);
	if (!i915_mch_dev) {
		ret = false;
		goto out_unlock;
	}
	dev_priv = i915_mch_dev;

	if (dev_priv->max_delay > dev_priv->fmax)
		dev_priv->max_delay--;

out_unlock:
	spin_unlock(&mchdev_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(i915_gpu_raise);

/**
 * i915_gpu_lower - lower GPU frequency limit
 *
 * IPS indicates we're close to a thermal limit, so throttle back the GPU
 * frequency maximum.
 */
bool i915_gpu_lower(void)
{
	struct drm_i915_private *dev_priv;
	bool ret = true;

	spin_lock(&mchdev_lock);
	if (!i915_mch_dev) {
		ret = false;
		goto out_unlock;
	}
	dev_priv = i915_mch_dev;

	if (dev_priv->max_delay < dev_priv->min_delay)
		dev_priv->max_delay++;

out_unlock:
	spin_unlock(&mchdev_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(i915_gpu_lower);

/**
 * i915_gpu_busy - indicate GPU business to IPS
 *
 * Tell the IPS driver whether or not the GPU is busy.
 */
bool i915_gpu_busy(void)
{
	struct drm_i915_private *dev_priv;
	bool ret = false;

	spin_lock(&mchdev_lock);
	if (!i915_mch_dev)
		goto out_unlock;
	dev_priv = i915_mch_dev;

	ret = dev_priv->busy;

out_unlock:
	spin_unlock(&mchdev_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(i915_gpu_busy);

/**
 * i915_gpu_turbo_disable - disable graphics turbo
 *
 * Disable graphics turbo by resetting the max frequency and setting the
 * current frequency to the default.
 */
bool i915_gpu_turbo_disable(void)
{
	struct drm_i915_private *dev_priv;
	bool ret = true;

	spin_lock(&mchdev_lock);
	if (!i915_mch_dev) {
		ret = false;
		goto out_unlock;
	}
	dev_priv = i915_mch_dev;

	dev_priv->max_delay = dev_priv->fstart;

	if (!ironlake_set_drps(dev_priv->dev, dev_priv->fstart))
		ret = false;

out_unlock:
	spin_unlock(&mchdev_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(i915_gpu_turbo_disable);

/**
 * Tells the intel_ips driver that the i915 driver is now loaded, if
 * IPS got loaded first.
 *
 * This awkward dance is so that neither module has to depend on the
 * other in order for IPS to do the appropriate communication of
 * GPU turbo limits to i915.
 */
static void
ips_ping_for_i915_load(void)
{
	void (*link)(void);

	link = symbol_get(ips_link_to_i915_driver);
	if (link) {
		link();
		symbol_put(ips_link_to_i915_driver);
	}
}

void intel_gpu_ips_init(struct drm_i915_private *dev_priv)
{
	spin_lock(&mchdev_lock);
	i915_mch_dev = dev_priv;
	dev_priv->mchdev_lock = &mchdev_lock;
	spin_unlock(&mchdev_lock);

	ips_ping_for_i915_load();
}

void intel_gpu_ips_teardown(void)
{
	spin_lock(&mchdev_lock);
	i915_mch_dev = NULL;
	spin_unlock(&mchdev_lock);
}
static void intel_init_emon(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 lcfuse;
	u8 pxw[16];
	int i;

	/* Disable to program */
	I915_WRITE(ECR, 0);
	POSTING_READ(ECR);

	/* Program energy weights for various events */
	I915_WRITE(SDEW, 0x15040d00);
	I915_WRITE(CSIEW0, 0x007f0000);
	I915_WRITE(CSIEW1, 0x1e220004);
	I915_WRITE(CSIEW2, 0x04000004);

	for (i = 0; i < 5; i++)
		I915_WRITE(PEW + (i * 4), 0);
	for (i = 0; i < 3; i++)
		I915_WRITE(DEW + (i * 4), 0);

	/* Program P-state weights to account for frequency power adjustment */
	for (i = 0; i < 16; i++) {
		u32 pxvidfreq = I915_READ(PXVFREQ_BASE + (i * 4));
		unsigned long freq = intel_pxfreq(pxvidfreq);
		unsigned long vid = (pxvidfreq & PXVFREQ_PX_MASK) >>
			PXVFREQ_PX_SHIFT;
		unsigned long val;

		val = vid * vid;
		val *= (freq / 1000);
		val *= 255;
		val /= (127*127*900);
		if (val > 0xff)
			DRM_ERROR("bad pxval: %ld\n", val);
		pxw[i] = val;
	}
	/* Render standby states get 0 weight */
	pxw[14] = 0;
	pxw[15] = 0;

	for (i = 0; i < 4; i++) {
		u32 val = (pxw[i*4] << 24) | (pxw[(i*4)+1] << 16) |
			(pxw[(i*4)+2] << 8) | (pxw[(i*4)+3]);
		I915_WRITE(PXW + (i * 4), val);
	}

	/* Adjust magic regs to magic values (more experimental results) */
	I915_WRITE(OGW0, 0);
	I915_WRITE(OGW1, 0);
	I915_WRITE(EG0, 0x00007f00);
	I915_WRITE(EG1, 0x0000000e);
	I915_WRITE(EG2, 0x000e0000);
	I915_WRITE(EG3, 0x68000300);
	I915_WRITE(EG4, 0x42000000);
	I915_WRITE(EG5, 0x00140031);
	I915_WRITE(EG6, 0);
	I915_WRITE(EG7, 0);

	for (i = 0; i < 8; i++)
		I915_WRITE(PXWL + (i * 4), 0);

	/* Enable PMON + select events */
	I915_WRITE(ECR, 0x80000019);

	lcfuse = I915_READ(LCFUSE02);

	dev_priv->corr = (lcfuse & LCFUSE_HIV_MASK);
}

void intel_disable_gt_powersave(struct drm_device *dev)
{
	if (IS_IRONLAKE_M(dev))
		ironlake_disable_drps(dev);
	else if (INTEL_INFO(dev)->gen >= 6 && !IS_VALLEYVIEW(dev))
		gen6_disable_rps(dev);
}

void intel_enable_gt_powersave(struct drm_device *dev)
{
	if (IS_IRONLAKE_M(dev)) {
		ironlake_enable_drps(dev);
		ironlake_enable_rc6(dev);
		intel_init_emon(dev);
	} else if ((IS_GEN6(dev) || IS_GEN7(dev)) && !IS_VALLEYVIEW(dev)) {
		gen6_enable_rps(dev);
		gen6_update_ring_freq(dev);
	}
}

static void ironlake_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;

	/* Required for FBC */
	dspclk_gate |= DPFCUNIT_CLOCK_GATE_DISABLE |
		DPFCRUNIT_CLOCK_GATE_DISABLE |
		DPFDUNIT_CLOCK_GATE_DISABLE;
	/* Required for CxSR */
	dspclk_gate |= DPARBUNIT_CLOCK_GATE_DISABLE;

	I915_WRITE(PCH_3DCGDIS0,
		   MARIUNIT_CLOCK_GATE_DISABLE |
		   SVSMUNIT_CLOCK_GATE_DISABLE);
	I915_WRITE(PCH_3DCGDIS1,
		   VFMUNIT_CLOCK_GATE_DISABLE);

	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);

	/*
	 * According to the spec the following bits should be set in
	 * order to enable memory self-refresh
	 * The bit 22/21 of 0x42004
	 * The bit 5 of 0x42020
	 * The bit 15 of 0x45000
	 */
	I915_WRITE(ILK_DISPLAY_CHICKEN2,
		   (I915_READ(ILK_DISPLAY_CHICKEN2) |
		    ILK_DPARB_GATE | ILK_VSDPFD_FULL));
	I915_WRITE(ILK_DSPCLK_GATE,
		   (I915_READ(ILK_DSPCLK_GATE) |
		    ILK_DPARB_CLK_GATE));
	I915_WRITE(DISP_ARB_CTL,
		   (I915_READ(DISP_ARB_CTL) |
		    DISP_FBC_WM_DIS));
	I915_WRITE(WM3_LP_ILK, 0);
	I915_WRITE(WM2_LP_ILK, 0);
	I915_WRITE(WM1_LP_ILK, 0);

	/*
	 * Based on the document from hardware guys the following bits
	 * should be set unconditionally in order to enable FBC.
	 * The bit 22 of 0x42000
	 * The bit 22 of 0x42004
	 * The bit 7,8,9 of 0x42020.
	 */
	if (IS_IRONLAKE_M(dev)) {
		I915_WRITE(ILK_DISPLAY_CHICKEN1,
			   I915_READ(ILK_DISPLAY_CHICKEN1) |
			   ILK_FBCQ_DIS);
		I915_WRITE(ILK_DISPLAY_CHICKEN2,
			   I915_READ(ILK_DISPLAY_CHICKEN2) |
			   ILK_DPARB_GATE);
		I915_WRITE(ILK_DSPCLK_GATE,
			   I915_READ(ILK_DSPCLK_GATE) |
			   ILK_DPFC_DIS1 |
			   ILK_DPFC_DIS2 |
			   ILK_CLK_FBC);
	}

	I915_WRITE(ILK_DISPLAY_CHICKEN2,
		   I915_READ(ILK_DISPLAY_CHICKEN2) |
		   ILK_ELPIN_409_SELECT);
	I915_WRITE(_3D_CHICKEN2,
		   _3D_CHICKEN2_WM_READ_PIPELINED << 16 |
		   _3D_CHICKEN2_WM_READ_PIPELINED);
}

static void gen6_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int pipe;
	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;

	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);

	I915_WRITE(ILK_DISPLAY_CHICKEN2,
		   I915_READ(ILK_DISPLAY_CHICKEN2) |
		   ILK_ELPIN_409_SELECT);

	I915_WRITE(WM3_LP_ILK, 0);
	I915_WRITE(WM2_LP_ILK, 0);
	I915_WRITE(WM1_LP_ILK, 0);

	I915_WRITE(CACHE_MODE_0,
		   _MASKED_BIT_DISABLE(CM0_STC_EVICT_DISABLE_LRA_SNB));

	I915_WRITE(GEN6_UCGCTL1,
		   I915_READ(GEN6_UCGCTL1) |
		   GEN6_BLBUNIT_CLOCK_GATE_DISABLE |
		   GEN6_CSUNIT_CLOCK_GATE_DISABLE);

	/* According to the BSpec vol1g, bit 12 (RCPBUNIT) clock
	 * gating disable must be set.  Failure to set it results in
	 * flickering pixels due to Z write ordering failures after
	 * some amount of runtime in the Mesa "fire" demo, and Unigine
	 * Sanctuary and Tropics, and apparently anything else with
	 * alpha test or pixel discard.
	 *
	 * According to the spec, bit 11 (RCCUNIT) must also be set,
	 * but we didn't debug actual testcases to find it out.
	 *
	 * Also apply WaDisableVDSUnitClockGating and
	 * WaDisableRCPBUnitClockGating.
	 */
	I915_WRITE(GEN6_UCGCTL2,
		   GEN7_VDSUNIT_CLOCK_GATE_DISABLE |
		   GEN6_RCPBUNIT_CLOCK_GATE_DISABLE |
		   GEN6_RCCUNIT_CLOCK_GATE_DISABLE);

	/* Bspec says we need to always set all mask bits. */
	I915_WRITE(_3D_CHICKEN, (0xFFFF << 16) |
		   _3D_CHICKEN_SF_DISABLE_FASTCLIP_CULL);

	/*
	 * According to the spec the following bits should be
	 * set in order to enable memory self-refresh and fbc:
	 * The bit21 and bit22 of 0x42000
	 * The bit21 and bit22 of 0x42004
	 * The bit5 and bit7 of 0x42020
	 * The bit14 of 0x70180
	 * The bit14 of 0x71180
	 */
	I915_WRITE(ILK_DISPLAY_CHICKEN1,
		   I915_READ(ILK_DISPLAY_CHICKEN1) |
		   ILK_FBCQ_DIS | ILK_PABSTRETCH_DIS);
	I915_WRITE(ILK_DISPLAY_CHICKEN2,
		   I915_READ(ILK_DISPLAY_CHICKEN2) |
		   ILK_DPARB_GATE | ILK_VSDPFD_FULL);
	I915_WRITE(ILK_DSPCLK_GATE,
		   I915_READ(ILK_DSPCLK_GATE) |
		   ILK_DPARB_CLK_GATE  |
		   ILK_DPFD_CLK_GATE);

	I915_WRITE(GEN6_MBCTL, I915_READ(GEN6_MBCTL) |
		   GEN6_MBCTL_ENABLE_BOOT_FETCH);

	for_each_pipe(pipe) {
		I915_WRITE(DSPCNTR(pipe),
			   I915_READ(DSPCNTR(pipe)) |
			   DISPPLANE_TRICKLE_FEED_DISABLE);
		intel_flush_display_plane(dev_priv, pipe);
	}
}

static void gen7_setup_fixed_func_scheduler(struct drm_i915_private *dev_priv)
{
	uint32_t reg = I915_READ(GEN7_FF_THREAD_MODE);

	reg &= ~GEN7_FF_SCHED_MASK;
	reg |= GEN7_FF_TS_SCHED_HW;
	reg |= GEN7_FF_VS_SCHED_HW;
	reg |= GEN7_FF_DS_SCHED_HW;

	I915_WRITE(GEN7_FF_THREAD_MODE, reg);
}

static void haswell_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int pipe;
	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;

	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);

	I915_WRITE(WM3_LP_ILK, 0);
	I915_WRITE(WM2_LP_ILK, 0);
	I915_WRITE(WM1_LP_ILK, 0);

	/* According to the spec, bit 13 (RCZUNIT) must be set on IVB.
	 * This implements the WaDisableRCZUnitClockGating workaround.
	 */
	I915_WRITE(GEN6_UCGCTL2, GEN6_RCZUNIT_CLOCK_GATE_DISABLE);

	I915_WRITE(ILK_DSPCLK_GATE, IVB_VRHUNIT_CLK_GATE);

	I915_WRITE(IVB_CHICKEN3,
		   CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE |
		   CHICKEN3_DGMG_DONE_FIX_DISABLE);

	/* Apply the WaDisableRHWOOptimizationForRenderHang workaround. */
	I915_WRITE(GEN7_COMMON_SLICE_CHICKEN1,
		   GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC);

	/* WaApplyL3ControlAndL3ChickenMode requires those two on Ivy Bridge */
	I915_WRITE(GEN7_L3CNTLREG1,
			GEN7_WA_FOR_GEN7_L3_CONTROL);
	I915_WRITE(GEN7_L3_CHICKEN_MODE_REGISTER,
			GEN7_WA_L3_CHICKEN_MODE);

	/* This is required by WaCatErrorRejectionIssue */
	I915_WRITE(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG,
			I915_READ(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG) |
			GEN7_SQ_CHICKEN_MBCUNIT_SQINTMOB);

	for_each_pipe(pipe) {
		I915_WRITE(DSPCNTR(pipe),
			   I915_READ(DSPCNTR(pipe)) |
			   DISPPLANE_TRICKLE_FEED_DISABLE);
		intel_flush_display_plane(dev_priv, pipe);
	}

	gen7_setup_fixed_func_scheduler(dev_priv);

	/* WaDisable4x2SubspanOptimization */
	I915_WRITE(CACHE_MODE_1,
		   _MASKED_BIT_ENABLE(PIXEL_SUBSPAN_COLLECT_OPT_DISABLE));

	/* XXX: This is a workaround for early silicon revisions and should be
	 * removed later.
	 */
	I915_WRITE(WM_DBG,
			I915_READ(WM_DBG) |
			WM_DBG_DISALLOW_MULTIPLE_LP |
			WM_DBG_DISALLOW_SPRITE |
			WM_DBG_DISALLOW_MAXFIFO);

}

static void ivybridge_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int pipe;
	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;
	uint32_t snpcr;

	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);

	I915_WRITE(WM3_LP_ILK, 0);
	I915_WRITE(WM2_LP_ILK, 0);
	I915_WRITE(WM1_LP_ILK, 0);

	I915_WRITE(ILK_DSPCLK_GATE, IVB_VRHUNIT_CLK_GATE);

	I915_WRITE(IVB_CHICKEN3,
		   CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE |
		   CHICKEN3_DGMG_DONE_FIX_DISABLE);

	/* Apply the WaDisableRHWOOptimizationForRenderHang workaround. */
	I915_WRITE(GEN7_COMMON_SLICE_CHICKEN1,
		   GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC);

	/* WaApplyL3ControlAndL3ChickenMode requires those two on Ivy Bridge */
	I915_WRITE(GEN7_L3CNTLREG1,
			GEN7_WA_FOR_GEN7_L3_CONTROL);
	I915_WRITE(GEN7_L3_CHICKEN_MODE_REGISTER,
			GEN7_WA_L3_CHICKEN_MODE);

	/* According to the BSpec vol1g, bit 12 (RCPBUNIT) clock
	 * gating disable must be set.  Failure to set it results in
	 * flickering pixels due to Z write ordering failures after
	 * some amount of runtime in the Mesa "fire" demo, and Unigine
	 * Sanctuary and Tropics, and apparently anything else with
	 * alpha test or pixel discard.
	 *
	 * According to the spec, bit 11 (RCCUNIT) must also be set,
	 * but we didn't debug actual testcases to find it out.
	 *
	 * According to the spec, bit 13 (RCZUNIT) must be set on IVB.
	 * This implements the WaDisableRCZUnitClockGating workaround.
	 */
	I915_WRITE(GEN6_UCGCTL2,
		   GEN6_RCZUNIT_CLOCK_GATE_DISABLE |
		   GEN6_RCCUNIT_CLOCK_GATE_DISABLE);

	/* This is required by WaCatErrorRejectionIssue */
	I915_WRITE(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG,
			I915_READ(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG) |
			GEN7_SQ_CHICKEN_MBCUNIT_SQINTMOB);

	for_each_pipe(pipe) {
		I915_WRITE(DSPCNTR(pipe),
			   I915_READ(DSPCNTR(pipe)) |
			   DISPPLANE_TRICKLE_FEED_DISABLE);
		intel_flush_display_plane(dev_priv, pipe);
	}

	I915_WRITE(GEN6_MBCTL, I915_READ(GEN6_MBCTL) |
		   GEN6_MBCTL_ENABLE_BOOT_FETCH);

	gen7_setup_fixed_func_scheduler(dev_priv);

	/* WaDisable4x2SubspanOptimization */
	I915_WRITE(CACHE_MODE_1,
		   _MASKED_BIT_ENABLE(PIXEL_SUBSPAN_COLLECT_OPT_DISABLE));

	snpcr = I915_READ(GEN6_MBCUNIT_SNPCR);
	snpcr &= ~GEN6_MBC_SNPCR_MASK;
	snpcr |= GEN6_MBC_SNPCR_MED;
	I915_WRITE(GEN6_MBCUNIT_SNPCR, snpcr);
}

static void valleyview_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int pipe;
	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;

	I915_WRITE(PCH_DSPCLK_GATE_D, dspclk_gate);

	I915_WRITE(WM3_LP_ILK, 0);
	I915_WRITE(WM2_LP_ILK, 0);
	I915_WRITE(WM1_LP_ILK, 0);

	I915_WRITE(ILK_DSPCLK_GATE, IVB_VRHUNIT_CLK_GATE);

	I915_WRITE(IVB_CHICKEN3,
		   CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE |
		   CHICKEN3_DGMG_DONE_FIX_DISABLE);

	/* Apply the WaDisableRHWOOptimizationForRenderHang workaround. */
	I915_WRITE(GEN7_COMMON_SLICE_CHICKEN1,
		   GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC);

	/* WaApplyL3ControlAndL3ChickenMode requires those two on Ivy Bridge */
	I915_WRITE(GEN7_L3CNTLREG1, GEN7_WA_FOR_GEN7_L3_CONTROL);
	I915_WRITE(GEN7_L3_CHICKEN_MODE_REGISTER, GEN7_WA_L3_CHICKEN_MODE);

	/* This is required by WaCatErrorRejectionIssue */
	I915_WRITE(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG,
		   I915_READ(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG) |
		   GEN7_SQ_CHICKEN_MBCUNIT_SQINTMOB);

	I915_WRITE(GEN6_MBCTL, I915_READ(GEN6_MBCTL) |
		   GEN6_MBCTL_ENABLE_BOOT_FETCH);


	/* According to the BSpec vol1g, bit 12 (RCPBUNIT) clock
	 * gating disable must be set.  Failure to set it results in
	 * flickering pixels due to Z write ordering failures after
	 * some amount of runtime in the Mesa "fire" demo, and Unigine
	 * Sanctuary and Tropics, and apparently anything else with
	 * alpha test or pixel discard.
	 *
	 * According to the spec, bit 11 (RCCUNIT) must also be set,
	 * but we didn't debug actual testcases to find it out.
	 *
	 * According to the spec, bit 13 (RCZUNIT) must be set on IVB.
	 * This implements the WaDisableRCZUnitClockGating workaround.
	 *
	 * Also apply WaDisableVDSUnitClockGating and
	 * WaDisableRCPBUnitClockGating.
	 */
	I915_WRITE(GEN6_UCGCTL2,
		   GEN7_VDSUNIT_CLOCK_GATE_DISABLE |
		   GEN7_TDLUNIT_CLOCK_GATE_DISABLE |
		   GEN6_RCZUNIT_CLOCK_GATE_DISABLE |
		   GEN6_RCPBUNIT_CLOCK_GATE_DISABLE |
		   GEN6_RCCUNIT_CLOCK_GATE_DISABLE);

	I915_WRITE(GEN7_UCGCTL4, GEN7_L3BANK2X_CLOCK_GATE_DISABLE);

	for_each_pipe(pipe) {
		I915_WRITE(DSPCNTR(pipe),
			   I915_READ(DSPCNTR(pipe)) |
			   DISPPLANE_TRICKLE_FEED_DISABLE);
		intel_flush_display_plane(dev_priv, pipe);
	}

	I915_WRITE(CACHE_MODE_1,
		   _MASKED_BIT_ENABLE(PIXEL_SUBSPAN_COLLECT_OPT_DISABLE));

	/*
	 * On ValleyView, the GUnit needs to signal the GT
	 * when flip and other events complete.  So enable
	 * all the GUnit->GT interrupts here
	 */
	I915_WRITE(VLV_DPFLIPSTAT, PIPEB_LINE_COMPARE_INT_EN |
		   PIPEB_HLINE_INT_EN | PIPEB_VBLANK_INT_EN |
		   SPRITED_FLIPDONE_INT_EN | SPRITEC_FLIPDONE_INT_EN |
		   PLANEB_FLIPDONE_INT_EN | PIPEA_LINE_COMPARE_INT_EN |
		   PIPEA_HLINE_INT_EN | PIPEA_VBLANK_INT_EN |
		   SPRITEB_FLIPDONE_INT_EN | SPRITEA_FLIPDONE_INT_EN |
		   PLANEA_FLIPDONE_INT_EN);
}

static void g4x_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	uint32_t dspclk_gate;

	I915_WRITE(RENCLK_GATE_D1, 0);
	I915_WRITE(RENCLK_GATE_D2, VF_UNIT_CLOCK_GATE_DISABLE |
		   GS_UNIT_CLOCK_GATE_DISABLE |
		   CL_UNIT_CLOCK_GATE_DISABLE);
	I915_WRITE(RAMCLK_GATE_D, 0);
	dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE |
		OVRUNIT_CLOCK_GATE_DISABLE |
		OVCUNIT_CLOCK_GATE_DISABLE;
	if (IS_GM45(dev))
		dspclk_gate |= DSSUNIT_CLOCK_GATE_DISABLE;
	I915_WRITE(DSPCLK_GATE_D, dspclk_gate);
}

static void crestline_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	I915_WRITE(RENCLK_GATE_D1, I965_RCC_CLOCK_GATE_DISABLE);
	I915_WRITE(RENCLK_GATE_D2, 0);
	I915_WRITE(DSPCLK_GATE_D, 0);
	I915_WRITE(RAMCLK_GATE_D, 0);
	I915_WRITE16(DEUC, 0);
}

static void broadwater_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	I915_WRITE(RENCLK_GATE_D1, I965_RCZ_CLOCK_GATE_DISABLE |
		   I965_RCC_CLOCK_GATE_DISABLE |
		   I965_RCPB_CLOCK_GATE_DISABLE |
		   I965_ISC_CLOCK_GATE_DISABLE |
		   I965_FBC_CLOCK_GATE_DISABLE);
	I915_WRITE(RENCLK_GATE_D2, 0);
}

static void gen3_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 dstate = I915_READ(D_STATE);

	dstate |= DSTATE_PLL_D3_OFF | DSTATE_GFX_CLOCK_GATING |
		DSTATE_DOT_CLOCK_GATING;
	I915_WRITE(D_STATE, dstate);

	if (IS_PINEVIEW(dev))
		I915_WRITE(ECOSKPD, _MASKED_BIT_ENABLE(ECO_GATING_CX_ONLY));
}

static void i85x_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	I915_WRITE(RENCLK_GATE_D1, SV_CLOCK_GATE_DISABLE);
}

static void i830_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	I915_WRITE(DSPCLK_GATE_D, OVRUNIT_CLOCK_GATE_DISABLE);
}

static void ibx_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	/*
	 * On Ibex Peak and Cougar Point, we need to disable clock
	 * gating for the panel power sequencer or it will fail to
	 * start up when no ports are active.
	 */
	I915_WRITE(SOUTH_DSPCLK_GATE_D, PCH_DPLSUNIT_CLOCK_GATE_DISABLE);
}

static void cpt_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int pipe;

	/*
	 * On Ibex Peak and Cougar Point, we need to disable clock
	 * gating for the panel power sequencer or it will fail to
	 * start up when no ports are active.
	 */
	I915_WRITE(SOUTH_DSPCLK_GATE_D, PCH_DPLSUNIT_CLOCK_GATE_DISABLE);
	I915_WRITE(SOUTH_CHICKEN2, I915_READ(SOUTH_CHICKEN2) |
		   DPLS_EDP_PPS_FIX_DIS);
	/* Without this, mode sets may fail silently on FDI */
	for_each_pipe(pipe)
		I915_WRITE(TRANS_CHICKEN2(pipe), TRANS_AUTOTRAIN_GEN_STALL_DIS);
}

void intel_init_clock_gating(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	dev_priv->display.init_clock_gating(dev);

	if (dev_priv->display.init_pch_clock_gating)
		dev_priv->display.init_pch_clock_gating(dev);
}

static void gen6_sanitize_pm(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 limits, delay, old;

	gen6_gt_force_wake_get(dev_priv);

	old = limits = I915_READ(GEN6_RP_INTERRUPT_LIMITS);
	/* Make sure we continue to get interrupts
	 * until we hit the minimum or maximum frequencies.
	 */
	limits &= ~(0x3f << 16 | 0x3f << 24);
	delay = dev_priv->cur_delay;
	if (delay < dev_priv->max_delay)
		limits |= (dev_priv->max_delay & 0x3f) << 24;
	if (delay > dev_priv->min_delay)
		limits |= (dev_priv->min_delay & 0x3f) << 16;

	if (old != limits) {
		/* Note that the known failure case is to read back 0. */
		DRM_DEBUG_DRIVER("Power management discrepancy: GEN6_RP_INTERRUPT_LIMITS "
				 "expected %08x, was %08x\n", limits, old);
		I915_WRITE(GEN6_RP_INTERRUPT_LIMITS, limits);
	}

	gen6_gt_force_wake_put(dev_priv);
}

void intel_sanitize_pm(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (dev_priv->display.sanitize_pm)
		dev_priv->display.sanitize_pm(dev);
}

/* Starting with Haswell, we have different power wells for
 * different parts of the GPU. This attempts to enable them all.
 */
void intel_init_power_wells(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	unsigned long power_wells[] = {
		HSW_PWR_WELL_CTL1,
		HSW_PWR_WELL_CTL2,
		HSW_PWR_WELL_CTL4
	};
	int i;

	if (!IS_HASWELL(dev))
		return;

	mutex_lock(&dev->struct_mutex);

	for (i = 0; i < ARRAY_SIZE(power_wells); i++) {
		int well = I915_READ(power_wells[i]);

		if ((well & HSW_PWR_WELL_STATE) == 0) {
			I915_WRITE(power_wells[i], well & HSW_PWR_WELL_ENABLE);
			if (wait_for(I915_READ(power_wells[i] & HSW_PWR_WELL_STATE), 20))
				DRM_ERROR("Error enabling power well %lx\n", power_wells[i]);
		}
	}

	mutex_unlock(&dev->struct_mutex);
}

/* Set up chip specific power management-related functions */
void intel_init_pm(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (I915_HAS_FBC(dev)) {
		if (HAS_PCH_SPLIT(dev)) {
			dev_priv->display.fbc_enabled = ironlake_fbc_enabled;
			dev_priv->display.enable_fbc = ironlake_enable_fbc;
			dev_priv->display.disable_fbc = ironlake_disable_fbc;
		} else if (IS_GM45(dev)) {
			dev_priv->display.fbc_enabled = g4x_fbc_enabled;
			dev_priv->display.enable_fbc = g4x_enable_fbc;
			dev_priv->display.disable_fbc = g4x_disable_fbc;
		} else if (IS_CRESTLINE(dev)) {
			dev_priv->display.fbc_enabled = i8xx_fbc_enabled;
			dev_priv->display.enable_fbc = i8xx_enable_fbc;
			dev_priv->display.disable_fbc = i8xx_disable_fbc;
		}
		/* 855GM needs testing */
	}

	/* For cxsr */
	if (IS_PINEVIEW(dev))
		i915_pineview_get_mem_freq(dev);
	else if (IS_GEN5(dev))
		i915_ironlake_get_mem_freq(dev);

	/* For FIFO watermark updates */
	if (HAS_PCH_SPLIT(dev)) {
		if (HAS_PCH_IBX(dev))
			dev_priv->display.init_pch_clock_gating = ibx_init_clock_gating;
		else if (HAS_PCH_CPT(dev))
			dev_priv->display.init_pch_clock_gating = cpt_init_clock_gating;

		if (IS_GEN5(dev)) {
			if (I915_READ(MLTR_ILK) & ILK_SRLT_MASK)
				dev_priv->display.update_wm = ironlake_update_wm;
			else {
				DRM_DEBUG_KMS("Failed to get proper latency. "
					      "Disable CxSR\n");
				dev_priv->display.update_wm = NULL;
			}
			dev_priv->display.init_clock_gating = ironlake_init_clock_gating;
		} else if (IS_GEN6(dev)) {
			if (SNB_READ_WM0_LATENCY()) {
				dev_priv->display.update_wm = sandybridge_update_wm;
				dev_priv->display.update_sprite_wm = sandybridge_update_sprite_wm;
			} else {
				DRM_DEBUG_KMS("Failed to read display plane latency. "
					      "Disable CxSR\n");
				dev_priv->display.update_wm = NULL;
			}
			dev_priv->display.init_clock_gating = gen6_init_clock_gating;
			dev_priv->display.sanitize_pm = gen6_sanitize_pm;
		} else if (IS_IVYBRIDGE(dev)) {
			/* FIXME: detect B0+ stepping and use auto training */
			if (SNB_READ_WM0_LATENCY()) {
				dev_priv->display.update_wm = sandybridge_update_wm;
				dev_priv->display.update_sprite_wm = sandybridge_update_sprite_wm;
			} else {
				DRM_DEBUG_KMS("Failed to read display plane latency. "
					      "Disable CxSR\n");
				dev_priv->display.update_wm = NULL;
			}
			dev_priv->display.init_clock_gating = ivybridge_init_clock_gating;
			dev_priv->display.sanitize_pm = gen6_sanitize_pm;
		} else if (IS_HASWELL(dev)) {
			if (SNB_READ_WM0_LATENCY()) {
				dev_priv->display.update_wm = sandybridge_update_wm;
				dev_priv->display.update_sprite_wm = sandybridge_update_sprite_wm;
				dev_priv->display.update_linetime_wm = haswell_update_linetime_wm;
			} else {
				DRM_DEBUG_KMS("Failed to read display plane latency. "
					      "Disable CxSR\n");
				dev_priv->display.update_wm = NULL;
			}
			dev_priv->display.init_clock_gating = haswell_init_clock_gating;
			dev_priv->display.sanitize_pm = gen6_sanitize_pm;
		} else
			dev_priv->display.update_wm = NULL;
	} else if (IS_VALLEYVIEW(dev)) {
		dev_priv->display.update_wm = valleyview_update_wm;
		dev_priv->display.init_clock_gating =
			valleyview_init_clock_gating;
	} else if (IS_PINEVIEW(dev)) {
		if (!intel_get_cxsr_latency(IS_PINEVIEW_G(dev),
					    dev_priv->is_ddr3,
					    dev_priv->fsb_freq,
					    dev_priv->mem_freq)) {
			DRM_INFO("failed to find known CxSR latency "
				 "(found ddr%s fsb freq %d, mem freq %d), "
				 "disabling CxSR\n",
				 (dev_priv->is_ddr3 == 1) ? "3" : "2",
				 dev_priv->fsb_freq, dev_priv->mem_freq);
			/* Disable CxSR and never update its watermark again */
			pineview_disable_cxsr(dev);
			dev_priv->display.update_wm = NULL;
		} else
			dev_priv->display.update_wm = pineview_update_wm;
		dev_priv->display.init_clock_gating = gen3_init_clock_gating;
	} else if (IS_G4X(dev)) {
		dev_priv->display.update_wm = g4x_update_wm;
		dev_priv->display.init_clock_gating = g4x_init_clock_gating;
	} else if (IS_GEN4(dev)) {
		dev_priv->display.update_wm = i965_update_wm;
		if (IS_CRESTLINE(dev))
			dev_priv->display.init_clock_gating = crestline_init_clock_gating;
		else if (IS_BROADWATER(dev))
			dev_priv->display.init_clock_gating = broadwater_init_clock_gating;
	} else if (IS_GEN3(dev)) {
		dev_priv->display.update_wm = i9xx_update_wm;
		dev_priv->display.get_fifo_size = i9xx_get_fifo_size;
		dev_priv->display.init_clock_gating = gen3_init_clock_gating;
	} else if (IS_I865G(dev)) {
		dev_priv->display.update_wm = i830_update_wm;
		dev_priv->display.init_clock_gating = i85x_init_clock_gating;
		dev_priv->display.get_fifo_size = i830_get_fifo_size;
	} else if (IS_I85X(dev)) {
		dev_priv->display.update_wm = i9xx_update_wm;
		dev_priv->display.get_fifo_size = i85x_get_fifo_size;
		dev_priv->display.init_clock_gating = i85x_init_clock_gating;
	} else {
		dev_priv->display.update_wm = i830_update_wm;
		dev_priv->display.init_clock_gating = i830_init_clock_gating;
		if (IS_845G(dev))
			dev_priv->display.get_fifo_size = i845_get_fifo_size;
		else
			dev_priv->display.get_fifo_size = i830_get_fifo_size;
	}

	/* We attempt to init the necessary power wells early in the initialization
	 * time, so the subsystems that expect power to be enabled can work.
	 */
	intel_init_power_wells(dev);
}

static void __gen6_gt_wait_for_thread_c0(struct drm_i915_private *dev_priv)
{
	u32 gt_thread_status_mask;

	if (IS_HASWELL(dev_priv->dev))
		gt_thread_status_mask = GEN6_GT_THREAD_STATUS_CORE_MASK_HSW;
	else
		gt_thread_status_mask = GEN6_GT_THREAD_STATUS_CORE_MASK;

	/* w/a for a sporadic read returning 0 by waiting for the GT
	 * thread to wake up.
	 */
	if (wait_for_atomic_us((I915_READ_NOTRACE(GEN6_GT_THREAD_STATUS_REG) & gt_thread_status_mask) == 0, 500))
		DRM_ERROR("GT thread status wait timed out\n");
}

static void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
{
	u32 forcewake_ack;

	if (IS_HASWELL(dev_priv->dev))
		forcewake_ack = FORCEWAKE_ACK_HSW;
	else
		forcewake_ack = FORCEWAKE_ACK;

	if (wait_for_atomic_us((I915_READ_NOTRACE(forcewake_ack) & 1) == 0, 500))
		DRM_ERROR("Force wake wait timed out\n");

	I915_WRITE_NOTRACE(FORCEWAKE, 1);

	if (wait_for_atomic_us((I915_READ_NOTRACE(forcewake_ack) & 1), 500))
		DRM_ERROR("Force wake wait timed out\n");

	__gen6_gt_wait_for_thread_c0(dev_priv);
}

static void __gen6_gt_force_wake_mt_get(struct drm_i915_private *dev_priv)
{
	u32 forcewake_ack;

	if (IS_HASWELL(dev_priv->dev))
		forcewake_ack = FORCEWAKE_ACK_HSW;
	else
		forcewake_ack = FORCEWAKE_MT_ACK;

	if (wait_for_atomic_us((I915_READ_NOTRACE(forcewake_ack) & 1) == 0, 500))
		DRM_ERROR("Force wake wait timed out\n");

	I915_WRITE_NOTRACE(FORCEWAKE_MT, _MASKED_BIT_ENABLE(1));

	if (wait_for_atomic_us((I915_READ_NOTRACE(forcewake_ack) & 1), 500))
		DRM_ERROR("Force wake wait timed out\n");

	__gen6_gt_wait_for_thread_c0(dev_priv);
}

/*
 * Generally this is called implicitly by the register read function. However,
 * if some sequence requires the GT to not power down then this function should
 * be called at the beginning of the sequence followed by a call to
 * gen6_gt_force_wake_put() at the end of the sequence.
 */
void gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
{
	unsigned long irqflags;

	spin_lock_irqsave(&dev_priv->gt_lock, irqflags);
	if (dev_priv->forcewake_count++ == 0)
		dev_priv->gt.force_wake_get(dev_priv);
	spin_unlock_irqrestore(&dev_priv->gt_lock, irqflags);
}

void gen6_gt_check_fifodbg(struct drm_i915_private *dev_priv)
{
	u32 gtfifodbg;
	gtfifodbg = I915_READ_NOTRACE(GTFIFODBG);
	if (WARN(gtfifodbg & GT_FIFO_CPU_ERROR_MASK,
	     "MMIO read or write has been dropped %x\n", gtfifodbg))
		I915_WRITE_NOTRACE(GTFIFODBG, GT_FIFO_CPU_ERROR_MASK);
}

static void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
{
	I915_WRITE_NOTRACE(FORCEWAKE, 0);
	/* The below doubles as a POSTING_READ */
	gen6_gt_check_fifodbg(dev_priv);
}

static void __gen6_gt_force_wake_mt_put(struct drm_i915_private *dev_priv)
{
	I915_WRITE_NOTRACE(FORCEWAKE_MT, _MASKED_BIT_DISABLE(1));
	/* The below doubles as a POSTING_READ */
	gen6_gt_check_fifodbg(dev_priv);
}

/*
 * see gen6_gt_force_wake_get()
 */
void gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
{
	unsigned long irqflags;

	spin_lock_irqsave(&dev_priv->gt_lock, irqflags);
	if (--dev_priv->forcewake_count == 0)
		dev_priv->gt.force_wake_put(dev_priv);
	spin_unlock_irqrestore(&dev_priv->gt_lock, irqflags);
}

int __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv)
{
	int ret = 0;

	if (dev_priv->gt_fifo_count < GT_FIFO_NUM_RESERVED_ENTRIES) {
		int loop = 500;
		u32 fifo = I915_READ_NOTRACE(GT_FIFO_FREE_ENTRIES);
		while (fifo <= GT_FIFO_NUM_RESERVED_ENTRIES && loop--) {
			udelay(10);
			fifo = I915_READ_NOTRACE(GT_FIFO_FREE_ENTRIES);
		}
		if (WARN_ON(loop < 0 && fifo <= GT_FIFO_NUM_RESERVED_ENTRIES))
			++ret;
		dev_priv->gt_fifo_count = fifo;
	}
	dev_priv->gt_fifo_count--;

	return ret;
}

static void vlv_force_wake_get(struct drm_i915_private *dev_priv)
{
	/* Already awake? */
	if ((I915_READ(0x130094) & 0xa1) == 0xa1)
		return;

	I915_WRITE_NOTRACE(FORCEWAKE_VLV, 0xffffffff);
	POSTING_READ(FORCEWAKE_VLV);

	if (wait_for_atomic_us((I915_READ_NOTRACE(FORCEWAKE_ACK_VLV) & 1), 500))
		DRM_ERROR("Force wake wait timed out\n");

	__gen6_gt_wait_for_thread_c0(dev_priv);
}

static void vlv_force_wake_put(struct drm_i915_private *dev_priv)
{
	I915_WRITE_NOTRACE(FORCEWAKE_VLV, 0xffff0000);
	/* FIXME: confirm VLV behavior with Punit folks */
	POSTING_READ(FORCEWAKE_VLV);
}

void intel_gt_init(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	spin_lock_init(&dev_priv->gt_lock);

	if (IS_VALLEYVIEW(dev)) {
		dev_priv->gt.force_wake_get = vlv_force_wake_get;
		dev_priv->gt.force_wake_put = vlv_force_wake_put;
	} else if (INTEL_INFO(dev)->gen >= 6) {
		dev_priv->gt.force_wake_get = __gen6_gt_force_wake_get;
		dev_priv->gt.force_wake_put = __gen6_gt_force_wake_put;

		/* IVB configs may use multi-threaded forcewake */
		if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev)) {
			u32 ecobus;

			/* A small trick here - if the bios hasn't configured
			 * MT forcewake, and if the device is in RC6, then
			 * force_wake_mt_get will not wake the device and the
			 * ECOBUS read will return zero. Which will be
			 * (correctly) interpreted by the test below as MT
			 * forcewake being disabled.
			 */
			mutex_lock(&dev->struct_mutex);
			__gen6_gt_force_wake_mt_get(dev_priv);
			ecobus = I915_READ_NOTRACE(ECOBUS);
			__gen6_gt_force_wake_mt_put(dev_priv);
			mutex_unlock(&dev->struct_mutex);

			if (ecobus & FORCEWAKE_MT_ENABLE) {
				DRM_DEBUG_KMS("Using MT version of forcewake\n");
				dev_priv->gt.force_wake_get =
					__gen6_gt_force_wake_mt_get;
				dev_priv->gt.force_wake_put =
					__gen6_gt_force_wake_mt_put;
			}
		}
	}
}