drm/radeon/kms: fix r300 vram width calculations
This was incorrect according to the docs and the UMS driver does
it like this.
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/r300.c b/drivers/gpu/drm/radeon/r300.c
index e699e6d..43b55a0 100644
--- a/drivers/gpu/drm/radeon/r300.c
+++ b/drivers/gpu/drm/radeon/r300.c
@@ -506,11 +506,14 @@
/* DDR for all card after R300 & IGP */
rdev->mc.vram_is_ddr = true;
+
tmp = RREG32(RADEON_MEM_CNTL);
- if (tmp & R300_MEM_NUM_CHANNELS_MASK) {
- rdev->mc.vram_width = 128;
- } else {
- rdev->mc.vram_width = 64;
+ tmp &= R300_MEM_NUM_CHANNELS_MASK;
+ switch (tmp) {
+ case 0: rdev->mc.vram_width = 64; break;
+ case 1: rdev->mc.vram_width = 128; break;
+ case 2: rdev->mc.vram_width = 256; break;
+ default: rdev->mc.vram_width = 128; break;
}
r100_vram_init_sizes(rdev);