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-rw-r--r--arch/x86/kernel/Makefile2
-rw-r--r--arch/x86/kernel/sysfb.c71
-rw-r--r--arch/x86/kernel/sysfb_simplefb.c95
3 files changed, 168 insertions, 0 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 88d99ea77723..90ecdc5d471a 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -103,6 +103,8 @@ obj-$(CONFIG_X86_CHECK_BIOS_CORRUPTION) += check.o
obj-$(CONFIG_SWIOTLB) += pci-swiotlb.o
obj-$(CONFIG_OF) += devicetree.o
obj-$(CONFIG_UPROBES) += uprobes.o
+obj-y += sysfb.o
+obj-$(CONFIG_X86_SYSFB) += sysfb_simplefb.o
obj-$(CONFIG_PERF_EVENTS) += perf_regs.o
obj-$(CONFIG_TRACING) += tracepoint.o
diff --git a/arch/x86/kernel/sysfb.c b/arch/x86/kernel/sysfb.c
new file mode 100644
index 000000000000..7f30e194eb52
--- /dev/null
+++ b/arch/x86/kernel/sysfb.c
@@ -0,0 +1,71 @@
+/*
+ * Generic System Framebuffers on x86
+ * Copyright (c) 2012-2013 David Herrmann <dh.herrmann@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ */
+
+/*
+ * Simple-Framebuffer support for x86 systems
+ * Create a platform-device for any available boot framebuffer. The
+ * simple-framebuffer platform device is already available on DT systems, so
+ * this module parses the global "screen_info" object and creates a suitable
+ * platform device compatible with the "simple-framebuffer" DT object. If
+ * the framebuffer is incompatible, we instead create a legacy
+ * "vesa-framebuffer", "efi-framebuffer" or "platform-framebuffer" device and
+ * pass the screen_info as platform_data. This allows legacy drivers
+ * to pick these devices up without messing with simple-framebuffer drivers.
+ * The global "screen_info" is still valid at all times.
+ *
+ * If CONFIG_X86_SYSFB is not selected, we never register "simple-framebuffer"
+ * platform devices, but only use legacy framebuffer devices for
+ * backwards compatibility.
+ *
+ * TODO: We set the dev_id field of all platform-devices to 0. This allows
+ * other x86 OF/DT parsers to create such devices, too. However, they must
+ * start at offset 1 for this to work.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/platform_data/simplefb.h>
+#include <linux/platform_device.h>
+#include <linux/screen_info.h>
+#include <asm/sysfb.h>
+
+static __init int sysfb_init(void)
+{
+ struct screen_info *si = &screen_info;
+ struct simplefb_platform_data mode;
+ struct platform_device *pd;
+ const char *name;
+ bool compatible;
+ int ret;
+
+ /* try to create a simple-framebuffer device */
+ compatible = parse_mode(si, &mode);
+ if (compatible) {
+ ret = create_simplefb(si, &mode);
+ if (!ret)
+ return 0;
+ }
+
+ /* if the FB is incompatible, create a legacy framebuffer device */
+ if (si->orig_video_isVGA == VIDEO_TYPE_EFI)
+ name = "efi-framebuffer";
+ else if (si->orig_video_isVGA == VIDEO_TYPE_VLFB)
+ name = "vesa-framebuffer";
+ else
+ name = "platform-framebuffer";
+
+ pd = platform_device_register_resndata(NULL, name, 0,
+ NULL, 0, si, sizeof(*si));
+ return IS_ERR(pd) ? PTR_ERR(pd) : 0;
+}
+
+device_initcall(sysfb_init);
diff --git a/arch/x86/kernel/sysfb_simplefb.c b/arch/x86/kernel/sysfb_simplefb.c
new file mode 100644
index 000000000000..22513e96b012
--- /dev/null
+++ b/arch/x86/kernel/sysfb_simplefb.c
@@ -0,0 +1,95 @@
+/*
+ * Generic System Framebuffers on x86
+ * Copyright (c) 2012-2013 David Herrmann <dh.herrmann@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ */
+
+/*
+ * simple-framebuffer probing
+ * Try to convert "screen_info" into a "simple-framebuffer" compatible mode.
+ * If the mode is incompatible, we return "false" and let the caller create
+ * legacy nodes instead.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/platform_data/simplefb.h>
+#include <linux/platform_device.h>
+#include <linux/screen_info.h>
+#include <asm/sysfb.h>
+
+static const char simplefb_resname[] = "BOOTFB";
+static const struct simplefb_format formats[] = SIMPLEFB_FORMATS;
+
+/* try parsing x86 screen_info into a simple-framebuffer mode struct */
+__init bool parse_mode(const struct screen_info *si,
+ struct simplefb_platform_data *mode)
+{
+ const struct simplefb_format *f;
+ __u8 type;
+ unsigned int i;
+
+ type = si->orig_video_isVGA;
+ if (type != VIDEO_TYPE_VLFB && type != VIDEO_TYPE_EFI)
+ return false;
+
+ for (i = 0; i < ARRAY_SIZE(formats); ++i) {
+ f = &formats[i];
+ if (si->lfb_depth == f->bits_per_pixel &&
+ si->red_size == f->red.length &&
+ si->red_pos == f->red.offset &&
+ si->green_size == f->green.length &&
+ si->green_pos == f->green.offset &&
+ si->blue_size == f->blue.length &&
+ si->blue_pos == f->blue.offset &&
+ si->rsvd_size == f->transp.length &&
+ si->rsvd_pos == f->transp.offset) {
+ mode->format = f->name;
+ mode->width = si->lfb_width;
+ mode->height = si->lfb_height;
+ mode->stride = si->lfb_linelength;
+ return true;
+ }
+ }
+
+ return false;
+}
+
+__init int create_simplefb(const struct screen_info *si,
+ const struct simplefb_platform_data *mode)
+{
+ struct platform_device *pd;
+ struct resource res;
+ unsigned long len;
+
+ /* don't use lfb_size as it may contain the whole VMEM instead of only
+ * the part that is occupied by the framebuffer */
+ len = mode->height * mode->stride;
+ len = PAGE_ALIGN(len);
+ if (len > si->lfb_size << 16) {
+ printk(KERN_WARNING "sysfb: VRAM smaller than advertised\n");
+ return -EINVAL;
+ }
+
+ /* setup IORESOURCE_MEM as framebuffer memory */
+ memset(&res, 0, sizeof(res));
+ res.flags = IORESOURCE_MEM;
+ res.name = simplefb_resname;
+ res.start = si->lfb_base;
+ res.end = si->lfb_base + len - 1;
+ if (res.end <= res.start)
+ return -EINVAL;
+
+ pd = platform_device_register_resndata(NULL, "simple-framebuffer", 0,
+ &res, 1, mode, sizeof(*mode));
+ if (IS_ERR(pd))
+ return PTR_ERR(pd);
+
+ return 0;
+}