From: Egbert Eich Date: Fri, 26 Jul 2013 12:14:24 +0000 (+0200) Subject: drm/i915: Add messages useful for HPD storm detection debugging (v2) X-Git-Tag: v3.12-rc2~3^2~143^2~4 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b8f102e8bf71cacf33326360fdf9dcfd1a63925b;p=kernel%2Fkernel-generic.git drm/i915: Add messages useful for HPD storm detection debugging (v2) For HPD storm detection we now mask out individual interrupt source bits. We have already seen a case where HPD interrupt enable bits were assigned to the wrong pins. To track these conditions more easily add some debugging messages. v2: Spelling fixes as suggested by Jani Nikula Signed-off-by: Egbert Eich Reviewed-by: Jani Nikula Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index ee3e49c..6a1c207 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -919,6 +919,10 @@ static inline void intel_hpd_irq_handler(struct drm_device *dev, spin_lock(&dev_priv->irq_lock); for (i = 1; i < HPD_NUM_PINS; i++) { + WARN(((hpd[i] & hotplug_trigger) && + dev_priv->hpd_stats[i].hpd_mark != HPD_ENABLED), + "Received HPD interrupt although disabled\n"); + if (!(hpd[i] & hotplug_trigger) || dev_priv->hpd_stats[i].hpd_mark != HPD_ENABLED) continue; @@ -929,6 +933,7 @@ static inline void intel_hpd_irq_handler(struct drm_device *dev, + msecs_to_jiffies(HPD_STORM_DETECT_PERIOD))) { dev_priv->hpd_stats[i].hpd_last_jiffies = jiffies; dev_priv->hpd_stats[i].hpd_cnt = 0; + DRM_DEBUG_KMS("Received HPD interrupt on PIN %d - cnt: 0\n", i); } else if (dev_priv->hpd_stats[i].hpd_cnt > HPD_STORM_THRESHOLD) { dev_priv->hpd_stats[i].hpd_mark = HPD_MARK_DISABLED; dev_priv->hpd_event_bits &= ~(1 << i); @@ -936,6 +941,8 @@ static inline void intel_hpd_irq_handler(struct drm_device *dev, storm_detected = true; } else { dev_priv->hpd_stats[i].hpd_cnt++; + DRM_DEBUG_KMS("Received HPD interrupt on PIN %d - cnt: %d\n", i, + dev_priv->hpd_stats[i].hpd_cnt); } }