drm/i915: The return of i915_gpu_info to debugfs

Once upon a time before we had automated GPU state capture upon hangs,
we had intel_gpu_dump. Now we come almost full circle and reinstate that
view of the current GPU queues and registers by using the error capture
facility to snapshot the GPU state when debugfs/.../i915_gpu_info is
opened - which should provided useful debugging to both the error
capture routines (without having to cause a hang and avoid the error
state being eaten by igt) and generally.

v2: Rename drm_i915_error_state to i915_gpu_state to alleviate some name
collisions between the error state dump and inspecting the gpu state.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170214164611.11381-1-chris@chris-wilson.co.uk

1 files changed, 31 insertions, 15 deletions

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 6cfdb64926d7..992bda004f6b 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -897,7 +897,7 @@ struct intel_device_info {
 
 struct intel_display_error_state;
 
-struct drm_i915_error_state {
+struct i915_gpu_state {
 	struct kref ref;
 	struct timeval time;
 	struct timeval boottime;
@@ -917,7 +917,7 @@ struct drm_i915_error_state {
 	u32 eir;
 	u32 pgtbl_er;
 	u32 ier;
-	u32 gtier[4];
+	u32 gtier[4], ngtier;
 	u32 ccid;
 	u32 derrmr;
 	u32 forcewake;
@@ -931,6 +931,7 @@ struct drm_i915_error_state {
 	u32 gab_ctl;
 	u32 gfx_mode;
 
+	u32 nfence;
 	u64 fence[I915_MAX_NUM_FENCES];
 	struct intel_overlay_error_state *overlay;
 	struct intel_display_error_state *display;
@@ -1512,11 +1513,6 @@ struct drm_i915_error_state_buf {
 	loff_t pos;
 };
 
-struct i915_error_state_file_priv {
-	struct drm_i915_private *i915;
-	struct drm_i915_error_state *error;
-};
-
 #define I915_RESET_TIMEOUT (10 * HZ) /* 10s */
 #define I915_FENCE_TIMEOUT (10 * HZ) /* 10s */
 
@@ -1533,7 +1529,7 @@ struct i915_gpu_error {
 	/* For reset and error_state handling. */
 	spinlock_t lock;
 	/* Protected by the above dev->gpu_error.lock. */
-	struct drm_i915_error_state *first_error;
+	struct i915_gpu_state *first_error;
 
 	unsigned long missed_irq_rings;
 
@@ -3574,7 +3570,7 @@ static inline void intel_display_crc_init(struct drm_i915_private *dev_priv) {}
 __printf(2, 3)
 void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...);
 int i915_error_state_to_str(struct drm_i915_error_state_buf *estr,
-			    const struct i915_error_state_file_priv *error);
+			    const struct i915_gpu_state *gpu);
 int i915_error_state_buf_init(struct drm_i915_error_state_buf *eb,
 			      struct drm_i915_private *i915,
 			      size_t count, loff_t pos);
@@ -3583,13 +3579,28 @@ static inline void i915_error_state_buf_release(
 {
 	kfree(eb->buf);
 }
+
+struct i915_gpu_state *i915_capture_gpu_state(struct drm_i915_private *i915);
 void i915_capture_error_state(struct drm_i915_private *dev_priv,
 			      u32 engine_mask,
 			      const char *error_msg);
-void i915_error_state_get(struct drm_device *dev,
-			  struct i915_error_state_file_priv *error_priv);
-void i915_error_state_put(struct i915_error_state_file_priv *error_priv);
-void i915_destroy_error_state(struct drm_i915_private *dev_priv);
+
+static inline struct i915_gpu_state *
+i915_gpu_state_get(struct i915_gpu_state *gpu)
+{
+	kref_get(&gpu->ref);
+	return gpu;
+}
+
+void __i915_gpu_state_free(struct kref *kref);
+static inline void i915_gpu_state_put(struct i915_gpu_state *gpu)
+{
+	if (gpu)
+		kref_put(&gpu->ref, __i915_gpu_state_free);
+}
+
+struct i915_gpu_state *i915_first_error_state(struct drm_i915_private *i915);
+void i915_reset_error_state(struct drm_i915_private *i915);
 
 #else
 
@@ -3599,7 +3610,13 @@ static inline void i915_capture_error_state(struct drm_i915_private *dev_priv,
 {
 }
 
-static inline void i915_destroy_error_state(struct drm_i915_private *dev_priv)
+static inline struct i915_gpu_state *
+i915_first_error_state(struct drm_i915_private *i915)
+{
+	return NULL;
+}
+
+static inline void i915_reset_error_state(struct drm_i915_private *i915)
 {
 }
 
@@ -3747,7 +3764,6 @@ extern void intel_overlay_print_error_state(struct drm_i915_error_state_buf *e,
 extern struct intel_display_error_state *
 intel_display_capture_error_state(struct drm_i915_private *dev_priv);
 extern void intel_display_print_error_state(struct drm_i915_error_state_buf *e,
-					    struct drm_i915_private *dev_priv,
 					    struct intel_display_error_state *error);
 
 int sandybridge_pcode_read(struct drm_i915_private *dev_priv, u32 mbox, u32 *val);