revert-drm-radeon-kms-properly-compute-group_size-on-6xx-7xx

Revert drm/radeon/kms: properly compute group_size on 6xx/7xx

From: Steve Conklin <sconklin@canonical.com>

We discovered a regression for Radeon users in our latest proposed
kernel for 2.6.35 (Maverick), and have isolated it to this patch:

http://git.kernel.org/?p=linux/kernel/git/longterm/linux-2.6.35.y.git;a=commit;h=b8e9a4a45f8427837f4dba89
+bda4d4e3f3a5c726

We took that patch as part of 2.6.35.10, and one of our testers has
reported that our build of that kernel also exhibits the problem.

These are mainline kernels built with the Ubuntu configs.
http://kernel.ubuntu.com/~kernel-ppa/mainline/v2.6.35.10-maverick/

Our bug report is here:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/703553

Upstream bug report:

https://bugzilla.kernel.org/show_bug.cgi?id=24802

Signed-off-by: Andi Kleen <ak@linux.intel.com>

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index cdddc4d4063a707cede7a15808776560b86d4a5f..abc2a661b92230e2d556e5d9ed3614fc58c3548e 100644 (file)
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -1597,11 +1597,8 @@ void r600_gpu_init(struct radeon_device *rdev)
        rdev->config.r600.tiling_npipes = rdev->config.r600.max_tile_pipes;
        rdev->config.r600.tiling_nbanks = 4 << ((ramcfg & NOOFBANK_MASK) >> NOOFBANK_SHIFT);
        tiling_config |= BANK_TILING((ramcfg & NOOFBANK_MASK) >> NOOFBANK_SHIFT);
-       tiling_config |= GROUP_SIZE((ramcfg & BURSTLENGTH_MASK) >> BURSTLENGTH_SHIFT);
-       if ((ramcfg & BURSTLENGTH_MASK) >> BURSTLENGTH_SHIFT)
-               rdev->config.r600.tiling_group_size = 512;
-       else
-               rdev->config.r600.tiling_group_size = 256;
+       tiling_config |= GROUP_SIZE(0);
+       rdev->config.r600.tiling_group_size = 256;
        tmp = (ramcfg & NOOFROWS_MASK) >> NOOFROWS_SHIFT;
        if (tmp > 3) {
                tiling_config |= ROW_TILING(3);

diff --git a/drivers/gpu/drm/radeon/rv770.c b/drivers/gpu/drm/radeon/rv770.c
index 082c3804415496f09b5ceb2990879759fd4736a7..67e807371a08fcb1b1e924bc37b362e138ccc4dc 100644 (file)
--- a/drivers/gpu/drm/radeon/rv770.c
+++ b/drivers/gpu/drm/radeon/rv770.c
@@ -627,11 +627,10 @@ static void rv770_gpu_init(struct radeon_device *rdev)
        else
                gb_tiling_config |= BANK_TILING((mc_arb_ramcfg & NOOFBANK_MASK) >> NOOFBANK_SHIFT);
        rdev->config.rv770.tiling_nbanks = 4 << ((gb_tiling_config >> 4) & 0x3);
-       gb_tiling_config |= GROUP_SIZE((mc_arb_ramcfg & BURSTLENGTH_MASK) >> BURSTLENGTH_SHIFT);
-       if ((mc_arb_ramcfg & BURSTLENGTH_MASK) >> BURSTLENGTH_SHIFT)
-               rdev->config.rv770.tiling_group_size = 512;
-       else
-               rdev->config.rv770.tiling_group_size = 256;
+
+       gb_tiling_config |= GROUP_SIZE(0);
+       rdev->config.rv770.tiling_group_size = 256;
+
        if (((mc_arb_ramcfg & NOOFROWS_MASK) >> NOOFROWS_SHIFT) > 3) {
                gb_tiling_config |= ROW_TILING(3);
                gb_tiling_config |= SAMPLE_SPLIT(3);