From a2b7d2ab53ac298fa7c45e081b400c5217525baf Mon Sep 17 00:00:00 2001
From: Eugeni Dodonov <eugeni.dodonov@intel.com>
Date: Thu, 10 Nov 2011 13:55:15 -0200
Subject: [PATCH] --- yaml --- r: 276735 b: refs/heads/master c:
 4ed0b577457eb6aeb7cdc7e7316576e63d15abb2 h: refs/heads/master i:   276733:
 679b061a0402091fa59a74a27f3f317c41cfdca8   276731:
 b383925bd9ef78c69624992558cba896200847dc   276727:
 ffcf82dbc6a5130291b5fdedd6281d9882a7c20d   276719:
 9f1ccd72f8976f1eccbfb0de3d46ef5bdb154032   276703:
 6eb2827504c6028b97582e84b227151ae022310b   276671:
 3d04eb3a53174e7b95724f29d91b23aa4ec117f6   276607:
 53df5b3927dcf5b0d48598703961628512e46ef5   276479:
 fb4d3be6a95f9de1b4e69d9f5ccc5225b084aa7d v: v3

---
 [refs]                                |  2 +-
 trunk/drivers/gpu/drm/i915/i915_dma.c | 10 ++++++++++
 trunk/drivers/gpu/drm/i915/i915_drv.h |  1 +
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index cd4740798e7f..54a2b2fc354e 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 03d00ac53f9bcde06ff7e33d6676083c18d569a4
+refs/heads/master: 4ed0b577457eb6aeb7cdc7e7316576e63d15abb2
diff --git a/trunk/drivers/gpu/drm/i915/i915_dma.c b/trunk/drivers/gpu/drm/i915/i915_dma.c
index a9533c54c93c..a9ae374861e7 100644
--- a/trunk/drivers/gpu/drm/i915/i915_dma.c
+++ b/trunk/drivers/gpu/drm/i915/i915_dma.c
@@ -1454,6 +1454,14 @@ unsigned long i915_chipset_val(struct drm_i915_private *dev_priv)
 
 	diff1 = now - dev_priv->last_time1;
 
+	/* Prevent division-by-zero if we are asking too fast.
+	 * Also, we don't get interesting results if we are polling
+	 * faster than once in 10ms, so just return the saved value
+	 * in such cases.
+	 */
+	if (diff1 <= 10)
+		return dev_priv->chipset_power;
+
 	count1 = I915_READ(DMIEC);
 	count2 = I915_READ(DDREC);
 	count3 = I915_READ(CSIEC);
@@ -1484,6 +1492,8 @@ unsigned long i915_chipset_val(struct drm_i915_private *dev_priv)
 	dev_priv->last_count1 = total_count;
 	dev_priv->last_time1 = now;
 
+	dev_priv->chipset_power = ret;
+
 	return ret;
 }
 
diff --git a/trunk/drivers/gpu/drm/i915/i915_drv.h b/trunk/drivers/gpu/drm/i915/i915_drv.h
index 8ba88cfc36de..39a72f642b33 100644
--- a/trunk/drivers/gpu/drm/i915/i915_drv.h
+++ b/trunk/drivers/gpu/drm/i915/i915_drv.h
@@ -713,6 +713,7 @@ typedef struct drm_i915_private {
 
 	u64 last_count1;
 	unsigned long last_time1;
+	unsigned long chipset_power;
 	u64 last_count2;
 	struct timespec last_time2;
 	unsigned long gfx_power;