1 files changed, 32 insertions, 4 deletions

diff --git a/drivers/video/sunxi_display.c b/drivers/video/sunxi_display.c
index f5f24fc020..dbda97e746 100644
--- a/drivers/video/sunxi_display.c
+++ b/drivers/video/sunxi_display.c
@@ -46,6 +46,7 @@ struct sunxi_display {
 	GraphicDevice graphic_device;
 	enum sunxi_monitor monitor;
 	unsigned int depth;
+	unsigned int fb_size;
 } sunxi_display;
 
 #ifdef CONFIG_VIDEO_HDMI
@@ -1060,6 +1061,11 @@ static const char *sunxi_get_mon_desc(enum sunxi_monitor monitor)
 	return NULL; /* never reached */
 }
 
+ulong board_get_usable_ram_top(ulong total_size)
+{
+	return gd->ram_top - CONFIG_SUNXI_MAX_FB_SIZE;
+}
+
 void *video_hw_init(void)
 {
 	static GraphicDevice *graphic_device = &sunxi_display.graphic_device;
@@ -1075,10 +1081,6 @@ void *video_hw_init(void)
 
 	memset(&sunxi_display, 0, sizeof(struct sunxi_display));
 
-	printf("Reserved %dkB of RAM for Framebuffer.\n",
-	       CONFIG_SUNXI_FB_SIZE >> 10);
-	gd->fb_base = gd->ram_top;
-
 	video_get_ctfb_res_modes(RES_MODE_1024x768, 24, &mode,
 				 &sunxi_display.depth, &options);
 #ifdef CONFIG_VIDEO_HDMI
@@ -1169,6 +1171,17 @@ void *video_hw_init(void)
 		       mode->yres, sunxi_get_mon_desc(sunxi_display.monitor));
 	}
 
+	sunxi_display.fb_size =
+		(mode->xres * mode->yres * 4 + 0xfff) & ~0xfff;
+	if (sunxi_display.fb_size > CONFIG_SUNXI_MAX_FB_SIZE) {
+		printf("Error need %dkB for fb, but only %dkB is reserved\n",
+		       sunxi_display.fb_size >> 10,
+		       CONFIG_SUNXI_MAX_FB_SIZE >> 10);
+		return NULL;
+	}
+
+	gd->fb_base = gd->bd->bi_dram[0].start +
+		      gd->bd->bi_dram[0].size - sunxi_display.fb_size;
 	sunxi_engines_init();
 	sunxi_mode_set(mode, gd->fb_base - CONFIG_SYS_SDRAM_BASE);
 
@@ -1194,6 +1207,7 @@ int sunxi_simplefb_setup(void *blob)
 {
 	static GraphicDevice *graphic_device = &sunxi_display.graphic_device;
 	int offset, ret;
+	u64 start, size;
 	const char *pipeline = NULL;
 
 #ifdef CONFIG_MACH_SUN4I
@@ -1237,6 +1251,20 @@ int sunxi_simplefb_setup(void *blob)
 		return 0; /* Keep older kernels working */
 	}
 
+	/*
+	 * Do not report the framebuffer as free RAM to the OS, note we cannot
+	 * use fdt_add_mem_rsv() here, because then it is still seen as RAM,
+	 * and e.g. Linux refuses to iomap RAM on ARM, see:
+	 * linux/arch/arm/mm/ioremap.c around line 301.
+	 */
+	start = gd->bd->bi_dram[0].start;
+	size = gd->bd->bi_dram[0].size - sunxi_display.fb_size;
+	ret = fdt_fixup_memory_banks(blob, &start, &size, 1);
+	if (ret) {
+		eprintf("Cannot setup simplefb: Error reserving memory\n");
+		return ret;
+	}
+
 	ret = fdt_setup_simplefb_node(blob, offset, gd->fb_base,
 			graphic_device->winSizeX, graphic_device->winSizeY,
 			graphic_device->winSizeX * graphic_device->gdfBytesPP,