drm/i915/lpt: Avoid early timeout during FDI PHY reset

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/1467110253-16046-3-git-send-email-imre.deak@intel.com
This commit is contained in:
Imre Deak 2016-06-28 13:37:31 +03:00
parent 0b786e41c7
commit cf3598c23c

View file

@ -8537,16 +8537,16 @@ static void lpt_reset_fdi_mphy(struct drm_i915_private *dev_priv)
tmp |= FDI_MPHY_IOSFSB_RESET_CTL;
I915_WRITE(SOUTH_CHICKEN2, tmp);
if (wait_for_atomic_us(I915_READ(SOUTH_CHICKEN2) &
FDI_MPHY_IOSFSB_RESET_STATUS, 100))
if (wait_for_us(I915_READ(SOUTH_CHICKEN2) &
FDI_MPHY_IOSFSB_RESET_STATUS, 100))
DRM_ERROR("FDI mPHY reset assert timeout\n");
tmp = I915_READ(SOUTH_CHICKEN2);
tmp &= ~FDI_MPHY_IOSFSB_RESET_CTL;
I915_WRITE(SOUTH_CHICKEN2, tmp);
if (wait_for_atomic_us((I915_READ(SOUTH_CHICKEN2) &
FDI_MPHY_IOSFSB_RESET_STATUS) == 0, 100))
if (wait_for_us((I915_READ(SOUTH_CHICKEN2) &
FDI_MPHY_IOSFSB_RESET_STATUS) == 0, 100))
DRM_ERROR("FDI mPHY reset de-assert timeout\n");
}