On 28/06/16 11:37, Imre Deak wrote:
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: 0351b93992aa ("drm/i915: Do not lie about atomic timeout granularity") CC: Chris Wilson <[email protected]> CC: Tvrtko Ursulin <[email protected]> Signed-off-by: Imre Deak <[email protected]> --- drivers/gpu/drm/i915/intel_dpll_mgr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dpll_mgr.c b/drivers/gpu/drm/i915/intel_dpll_mgr.c index c0eff15..e130c3e 100644 --- a/drivers/gpu/drm/i915/intel_dpll_mgr.c +++ b/drivers/gpu/drm/i915/intel_dpll_mgr.c @@ -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); /*
This one was a bit more work to verify but is definitely a non-atomic path as well.
Reviewed-by: Tvrtko Ursulin <[email protected]> Regards, Tvrtko _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
