Commit 0b786e41 authored by Imre Deak's avatar Imre Deak

drm/i915/bxt: Avoid early timeout during PLL enable

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.

I noticed this via the PLL locking timing out incorrectly, with this fix
I couldn't reproduce the problem.

Fixes: 0351b939 ("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: default avatarImre Deak <imre.deak@intel.com>
Reviewed-by: default avatarTvrtko Ursulin <tvrtko.ursulin@intel.com>
CC: drm-intel-fixes@lists.freedesktop.org
Link: http://patchwork.freedesktop.org/patch/msgid/1467110253-16046-2-git-send-email-imre.deak@intel.com
parent 9b613022
......@@ -1374,8 +1374,8 @@ static void bxt_ddi_pll_enable(struct drm_i915_private *dev_priv,
I915_WRITE(BXT_PORT_PLL_ENABLE(port), temp);
POSTING_READ(BXT_PORT_PLL_ENABLE(port));
if (wait_for_atomic_us((I915_READ(BXT_PORT_PLL_ENABLE(port)) &
PORT_PLL_LOCK), 200))
if (wait_for_us((I915_READ(BXT_PORT_PLL_ENABLE(port)) & PORT_PLL_LOCK),
200))
DRM_ERROR("PLL %d not locked\n", port);
/*
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment