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yaml --- r: 166019 b: refs/heads/master c: d660467 h: refs/heads/master i: 166017: e6c7c38 166015: e86f36c v: v3
git-mirror · Sep 17, 2009 · 5da0249 · 5da0249
1 parent 665c9b6
commit 5da0249
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Showing 2 changed files with 9 additions and 2 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: decbbcda2965fadb9fbaaf4f9e057ae554aa3cfe
+refs/heads/master: d660467c3ff2a0b7413e1b7a51452b34ffb49e5f
diff --git a/trunk/drivers/gpu/drm/i915/intel_display.c b/trunk/drivers/gpu/drm/i915/intel_display.c
@@ -2119,7 +2119,14 @@ static unsigned long intel_calculate_wm(unsigned long clock_in_khz,
 {
 	long entries_required, wm_size;
 
-	entries_required = (clock_in_khz * pixel_size * latency_ns) / 1000000;
+	/*
+	 * Note: we need to make sure we don't overflow for various clock &
+	 * latency values.
+	 * clocks go from a few thousand to several hundred thousand.
+	 * latency is usually a few thousand
+	 */
+	entries_required = ((clock_in_khz / 1000) * pixel_size * latency_ns) /
+		1000;
 	entries_required /= wm->cacheline_size;
 
 	DRM_DEBUG("FIFO entries required for mode: %d\n", entries_required);