diff options
| author | Dave Airlie <airlied@redhat.com> | 2010-07-20 13:15:31 +1000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-08-02 10:29:36 -0700 |
| commit | 2ef2b029013e81656ea6c24b4edc03f2db8854f4 (patch) | |
| tree | 402829da2ae0af184d781a2ffd742dc488fe0a5c /drivers/gpu/drm/i915 | |
| parent | ebd740e3f99377b1fd482d10d67eb56cf06a0509 (diff) | |
drm/i915: enable low power render writes on GEN3 hardware.
commit 944001201ca0196bcdb088129e5866a9f379d08c upstream.
A lot of 945GMs have had stability issues for a long time, this manifested as X hangs, blitter engine hangs, and lots of crashes.
one such report is at:
https://bugs.freedesktop.org/show_bug.cgi?id=20560
along with numerous distro bugzillas.
This only took a week of digging and hair ripping to figure out.
Tracked down and tested on a 945GM Lenovo T60,
previously running
x11perf -copypixwin500
or
x11perf -copywinpix500
repeatedly would cause the GPU to wedge within 4 or 5 tries, with random busy bits set.
After this patch no hangs were observed.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/gpu/drm/i915')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_gem.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 751bb77519d..37a9ea37d38 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -4985,6 +4985,16 @@ i915_gem_load(struct drm_device *dev) list_add(&dev_priv->mm.shrink_list, &shrink_list); spin_unlock(&shrink_list_lock); + /* On GEN3 we really need to make sure the ARB C3 LP bit is set */ + if (IS_GEN3(dev)) { + u32 tmp = I915_READ(MI_ARB_STATE); + if (!(tmp & MI_ARB_C3_LP_WRITE_ENABLE)) { + /* arb state is a masked write, so set bit + bit in mask */ + tmp = MI_ARB_C3_LP_WRITE_ENABLE | (MI_ARB_C3_LP_WRITE_ENABLE << MI_ARB_MASK_SHIFT); + I915_WRITE(MI_ARB_STATE, tmp); + } + } + /* Old X drivers will take 0-2 for front, back, depth buffers */ if (!drm_core_check_feature(dev, DRIVER_MODESET)) dev_priv->fence_reg_start = 3; |