From fa2a87e4c5cea2beba9deabcbaf54d1979fff419 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Fri, 8 Jul 2022 20:21:09 +0200 Subject: [PATCH] drm/gud: Fix endianness in gud_xrgb8888_to_color() helper MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit DRM formats are defined to be little-endian, unless the DRM_FORMAT_BIG_ENDIAN flag is set. Hence when converting from one format to another, multi-byte pixel values loaded from memory must be converted from little-endian to host-endian. Conversely, multi-byte pixel values written to memory must be converted from host-endian to little-endian. Currently only drm_fb_xrgb8888_to_rgb332_line() includes endianness handling. Fix gud_xrgb8888_to_color() on big-endian platforms by adding the missing endianness handling. Signed-off-by: Geert Uytterhoeven Signed-off-by: Noralf Trønnes Link: https://patchwork.freedesktop.org/patch/msgid/b47589ed5d8ca44e0956684412e3f16f3227f887.1657300532.git.geert@linux-m68k.org --- drivers/gpu/drm/gud/gud_pipe.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/gud/gud_pipe.c b/drivers/gpu/drm/gud/gud_pipe.c index 4873f9799f41..d42592f6daab 100644 --- a/drivers/gpu/drm/gud/gud_pipe.c +++ b/drivers/gpu/drm/gud/gud_pipe.c @@ -105,7 +105,8 @@ static size_t gud_xrgb8888_to_color(u8 *dst, const struct drm_format_info *forma unsigned int bits_per_pixel = 8 / block_width; u8 r, g, b, pix, *block = dst; /* Assign to silence compiler warning */ unsigned int x, y, width; - u32 *pix32; + __le32 *sbuf32; + u32 pix32; size_t len; /* Start on a byte boundary */ @@ -114,8 +115,8 @@ static size_t gud_xrgb8888_to_color(u8 *dst, const struct drm_format_info *forma len = drm_format_info_min_pitch(format, 0, width) * drm_rect_height(rect); for (y = rect->y1; y < rect->y2; y++) { - pix32 = src + (y * fb->pitches[0]); - pix32 += rect->x1; + sbuf32 = src + (y * fb->pitches[0]); + sbuf32 += rect->x1; for (x = 0; x < width; x++) { unsigned int pixpos = x % block_width; /* within byte from the left */ @@ -126,9 +127,10 @@ static size_t gud_xrgb8888_to_color(u8 *dst, const struct drm_format_info *forma *block = 0; } - r = *pix32 >> 16; - g = *pix32 >> 8; - b = *pix32++; + pix32 = le32_to_cpu(*sbuf32++); + r = pix32 >> 16; + g = pix32 >> 8; + b = pix32; switch (format->format) { case GUD_DRM_FORMAT_XRGB1111: -- 2.20.1