drm/mgag200: Fix LUT programming for 16bpp
Since there are only 32 (64) distinct color values for each color
in 16bpp Matrox hardware expects those in a 'dense' manner, ie in
the first 32 (64) entries of the respective color.
Signed-off-by: Egbert Eich <eich@suse.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index c8983f9..503a414 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -29,6 +29,7 @@
struct mga_crtc *mga_crtc = to_mga_crtc(crtc);
struct drm_device *dev = crtc->dev;
struct mga_device *mdev = dev->dev_private;
+ struct drm_framebuffer *fb = crtc->fb;
int i;
if (!crtc->enabled)
@@ -36,6 +37,28 @@
WREG8(DAC_INDEX + MGA1064_INDEX, 0);
+ if (fb && fb->bits_per_pixel == 16) {
+ int inc = (fb->depth == 15) ? 8 : 4;
+ u8 r, b;
+ for (i = 0; i < MGAG200_LUT_SIZE; i += inc) {
+ if (fb->depth == 16) {
+ if (i > (MGAG200_LUT_SIZE >> 1)) {
+ r = b = 0;
+ } else {
+ r = mga_crtc->lut_r[i << 1];
+ b = mga_crtc->lut_b[i << 1];
+ }
+ } else {
+ r = mga_crtc->lut_r[i];
+ b = mga_crtc->lut_b[i];
+ }
+ /* VGA registers */
+ WREG8(DAC_INDEX + MGA1064_COL_PAL, r);
+ WREG8(DAC_INDEX + MGA1064_COL_PAL, mga_crtc->lut_g[i]);
+ WREG8(DAC_INDEX + MGA1064_COL_PAL, b);
+ }
+ return;
+ }
for (i = 0; i < MGAG200_LUT_SIZE; i++) {
/* VGA registers */
WREG8(DAC_INDEX + MGA1064_COL_PAL, mga_crtc->lut_r[i]);