From 5872e389ace7e5eb0ea810690cddbf4209ca15d2 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Fri, 18 Jan 2013 16:31:14 +0000
Subject: [PATCH] --- yaml --- r: 358097 b: refs/heads/master c:
 e90a4ea534b110a43df87a05587c53cd78569467 h: refs/heads/master i:   358095:
 ffe23b6554e4289f60857f6f284106d6414472a1 v: v3

---
 [refs]                                   |  2 +-
 trunk/drivers/gpu/drm/udl/udl_transfer.c | 46 ++++++++++++++----------
 2 files changed, 29 insertions(+), 19 deletions(-)

diff --git a/[refs] b/[refs]
index 2a9ba89f10d8..97a9cbd5c736 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: bcb39af4486be07e896fc374a2336bad3104ae0a
+refs/heads/master: e90a4ea534b110a43df87a05587c53cd78569467
diff --git a/trunk/drivers/gpu/drm/udl/udl_transfer.c b/trunk/drivers/gpu/drm/udl/udl_transfer.c
index 142fee5f983f..f343db73e095 100644
--- a/trunk/drivers/gpu/drm/udl/udl_transfer.c
+++ b/trunk/drivers/gpu/drm/udl/udl_transfer.c
@@ -75,15 +75,19 @@ static int udl_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes)
 }
 #endif
 
-static inline u16 pixel32_to_be16p(const uint8_t *pixel)
+static inline u16 pixel32_to_be16(const uint32_t pixel)
 {
-	uint32_t pix = *(uint32_t *)pixel;
-	u16 retval;
+	return (((pixel >> 3) & 0x001f) |
+		((pixel >> 5) & 0x07e0) |
+		((pixel >> 8) & 0xf800));
+}
 
-	retval =  (((pix >> 3) & 0x001f) |
-		   ((pix >> 5) & 0x07e0) |
-		   ((pix >> 8) & 0xf800));
-	return retval;
+static bool pixel_repeats(const void *pixel, const uint32_t repeat, int bpp)
+{
+	if (bpp == 2)
+		return *(const uint16_t *)pixel == repeat;
+	else
+		return *(const uint32_t *)pixel == repeat;
 }
 
 /*
@@ -152,29 +156,33 @@ static void udl_compress_hline16(
 		prefetch_range((void *) pixel, (cmd_pixel_end - pixel) * bpp);
 
 		while (pixel < cmd_pixel_end) {
-			const u8 * const repeating_pixel = pixel;
-
-			if (bpp == 2)
-				*(uint16_t *)cmd = cpu_to_be16p((uint16_t *)pixel);
-			else if (bpp == 4)
-				*(uint16_t *)cmd = cpu_to_be16(pixel32_to_be16p(pixel));
+			const u8 *const start = pixel;
+			u32 repeating_pixel;
+
+			if (bpp == 2) {
+				repeating_pixel = *(uint16_t *)pixel;
+				*(uint16_t *)cmd = cpu_to_be16(repeating_pixel);
+			} else {
+				repeating_pixel = *(uint32_t *)pixel;
+				*(uint16_t *)cmd = cpu_to_be16(pixel32_to_be16(repeating_pixel));
+			}
 
 			cmd += 2;
 			pixel += bpp;
 
 			if (unlikely((pixel < cmd_pixel_end) &&
-				     (!memcmp(pixel, repeating_pixel, bpp)))) {
+				     (pixel_repeats(pixel, repeating_pixel, bpp)))) {
 				/* go back and fill in raw pixel count */
-				*raw_pixels_count_byte = (((repeating_pixel -
+				*raw_pixels_count_byte = (((start -
 						raw_pixel_start) / bpp) + 1) & 0xFF;
 
-				while ((pixel < cmd_pixel_end)
-				       && (!memcmp(pixel, repeating_pixel, bpp))) {
+				while ((pixel < cmd_pixel_end) &&
+				       (pixel_repeats(pixel, repeating_pixel, bpp))) {
 					pixel += bpp;
 				}
 
 				/* immediately after raw data is repeat byte */
-				*cmd++ = (((pixel - repeating_pixel) / bpp) - 1) & 0xFF;
+				*cmd++ = (((pixel - start) / bpp) - 1) & 0xFF;
 
 				/* Then start another raw pixel span */
 				raw_pixel_start = pixel;
@@ -223,6 +231,8 @@ int udl_render_hline(struct drm_device *dev, int bpp, struct urb **urb_ptr,
 	u8 *cmd = *urb_buf_ptr;
 	u8 *cmd_end = (u8 *) urb->transfer_buffer + urb->transfer_buffer_length;
 
+	BUG_ON(!(bpp == 2 || bpp == 4));
+
 	line_start = (u8 *) (front + byte_offset);
 	next_pixel = line_start;
 	line_end = next_pixel + byte_width;