drm/i915/hsw: Avoid early timeout during LCPLL disable/restore

Since wait_for_atomic doesn't re-check the wait-for condition after
expiry of the timeout it can fail when called from non-atomic context
even if the condition is set correctly before the expiry. Fix this by
using the non-atomic wait_for instead.

Fixes: 0351b93992 ("drm/i915: Do not lie about atomic timeout granularity")
CC: Chris Wilson <chris@chris-wilson.co.uk>
CC: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
CC: drm-intel-fixes@lists.freedesktop.org
Link: http://patchwork.freedesktop.org/patch/msgid/1467110253-16046-4-git-send-email-imre.deak@intel.com
This commit is contained in:
Imre Deak 2016-06-28 13:37:32 +03:00
parent cf3598c23c
commit f53dd63f11

View file

@ -9534,8 +9534,8 @@ static void hsw_disable_lcpll(struct drm_i915_private *dev_priv,
val |= LCPLL_CD_SOURCE_FCLK;
I915_WRITE(LCPLL_CTL, val);
if (wait_for_atomic_us(I915_READ(LCPLL_CTL) &
LCPLL_CD_SOURCE_FCLK_DONE, 1))
if (wait_for_us(I915_READ(LCPLL_CTL) &
LCPLL_CD_SOURCE_FCLK_DONE, 1))
DRM_ERROR("Switching to FCLK failed\n");
val = I915_READ(LCPLL_CTL);
@ -9608,8 +9608,8 @@ static void hsw_restore_lcpll(struct drm_i915_private *dev_priv)
val &= ~LCPLL_CD_SOURCE_FCLK;
I915_WRITE(LCPLL_CTL, val);
if (wait_for_atomic_us((I915_READ(LCPLL_CTL) &
LCPLL_CD_SOURCE_FCLK_DONE) == 0, 1))
if (wait_for_us((I915_READ(LCPLL_CTL) &
LCPLL_CD_SOURCE_FCLK_DONE) == 0, 1))
DRM_ERROR("Switching back to LCPLL failed\n");
}