From: Ben Widawsky Date: Thu, 9 Feb 2012 09:15:19 +0000 (+0100) Subject: drm/i915: catch gtfifo errors on forcewake_put X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=ee64cbdbf617067988168a4a49fcaabdd2743da6;p=linux-beck.git drm/i915: catch gtfifo errors on forcewake_put This is similar to a patch I wrote several months ago. It's been updated for the new FORCEWAKE_MT. As recommended by Chris Wilson, use WARN() instead of DRM_ERROR, so we can get a backtrace. This shouldn't impact performance too much as the extra register read can replace the POSTING_READ we had previously. Reviewed-by: Chris Wilson Signed-off-by: Ben Widawsky Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 189041984aba..d783e2b4c914 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -385,16 +385,27 @@ void gen6_gt_force_wake_get(struct drm_i915_private *dev_priv) spin_unlock_irqrestore(&dev_priv->gt_lock, irqflags); } +static void gen6_gt_check_fifodbg(struct drm_i915_private *dev_priv) +{ + u32 gtfifodbg; + gtfifodbg = I915_READ_NOTRACE(GTFIFODBG); + if (WARN(gtfifodbg & GT_FIFO_CPU_ERROR_MASK, + "MMIO read or write has been dropped %x\n", gtfifodbg)) + I915_WRITE_NOTRACE(GTFIFODBG, GT_FIFO_CPU_ERROR_MASK); +} + void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv) { I915_WRITE_NOTRACE(FORCEWAKE, 0); - POSTING_READ(FORCEWAKE); + /* The below doubles as a POSTING_READ */ + gen6_gt_check_fifodbg(dev_priv); } void __gen6_gt_force_wake_mt_put(struct drm_i915_private *dev_priv) { I915_WRITE_NOTRACE(FORCEWAKE_MT, (1<<16) | 0); - POSTING_READ(FORCEWAKE_MT); + /* The below doubles as a POSTING_READ */ + gen6_gt_check_fifodbg(dev_priv); } /*