Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / arch / x86 / kernel / sysfb_simplefb.c

diff --git a/kernel/arch/x86/kernel/sysfb_simplefb.c b/kernel/arch/x86/kernel/sysfb_simplefb.c
new file mode 100644 (file)
index 0000000..764a29f
--- /dev/null
+++ b/kernel/arch/x86/kernel/sysfb_simplefb.c
@@ -0,0 +1,92 @@
+/*
+ * 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 > (u64)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 | IORESOURCE_BUSY;
+       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));
+       return PTR_ERR_OR_ZERO(pd);
+}