ps3fb: Update for firmware 2.10

ps3fb: Update for firmware 2.10

As of PS3 firmware version 2.10, the GPU command buffer size must be at least 2
MiB large. Since we use only a small part of the GPU command buffer and don't
want to waste precious XDR memory, move the GPU command buffer back to the
start of the XDR memory reserved for ps3fb and let the unused part overlap with
the actual frame buffer.

Signed-off-by: Geert Uytterhoeven <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/video/ps3fb.c

···
 #define L1GPU_DISPLAY_SYNC_HSYNC		1
 #define L1GPU_DISPLAY_SYNC_VSYNC		2
 
-#define GPU_CMD_BUF_SIZE			(64 * 1024)
+#define GPU_CMD_BUF_SIZE			(2 * 1024 * 1024)
+#define GPU_FB_START				(64 * 1024)
 #define GPU_IOIF				(0x0d000000UL)
 #define GPU_ALIGN_UP(x)				_ALIGN_UP((x), 64)
 #define GPU_MAX_LINE_LENGTH			(65536 - 64)
···
 	if (src_line_length != dst_line_length)
 		line_length |= (u64)src_line_length << 32;
 
+	src_offset += GPU_FB_START;
 	status = lv1_gpu_context_attribute(ps3fb.context_handle,
 					   L1GPU_CONTEXT_ATTRIBUTE_FB_BLIT,
 					   dst_offset, GPU_IOIF + src_offset,
···
 
 	status = lv1_gpu_context_attribute(ps3fb.context_handle,
 					   L1GPU_CONTEXT_ATTRIBUTE_FB_SETUP,
-					   xdr_lpar + ps3fb.xdr_size,
-					   GPU_CMD_BUF_SIZE,
-					   GPU_IOIF + ps3fb.xdr_size, 0);
+					   xdr_lpar, GPU_CMD_BUF_SIZE,
+					   GPU_IOIF, 0);
 	if (status) {
 		dev_err(dev,
 			"%s: lv1_gpu_context_attribute FB_SETUP failed: %d\n",
···
 	struct task_struct *task;
 	unsigned long max_ps3fb_size;
 
+	if (ps3fb_videomemory.size < GPU_CMD_BUF_SIZE) {
+		dev_err(&dev->core, "%s: Not enough video memory\n", __func__);
+		return -ENOMEM;
+	}
+
 	status = ps3_open_hv_device(dev);
 	if (status) {
 		dev_err(&dev->core, "%s: ps3_open_hv_device failed\n",
···
 	/* Clear memory to prevent kernel info leakage into userspace */
 	memset(ps3fb.xdr_ea, 0, ps3fb_videomemory.size);
 
-	/* The GPU command buffer is at the end of video memory */
-	ps3fb.xdr_size = ps3fb_videomemory.size - GPU_CMD_BUF_SIZE;
+	/*
+	 * The GPU command buffer is at the start of video memory
+	 * As we don't use the full command buffer, we can put the actual
+	 * frame buffer at offset GPU_FB_START and save some precious XDR
+	 * memory
+	 */
+	ps3fb.xdr_ea += GPU_FB_START;
+	ps3fb.xdr_size = ps3fb_videomemory.size - GPU_FB_START;
 
 	retval = ps3fb_xdr_settings(xdr_lpar, &dev->core);
 	if (retval)