diff options
Diffstat (limited to 'drivers/gpu/drm/i915')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_dma.c | 10 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_drv.h | 1 |
2 files changed, 11 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index 8a3942c4f099..c72b590f7d81 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -1453,6 +1453,14 @@ 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); @@ -1483,6 +1491,8 @@ 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/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 7916bd97d5c1..1a2a2d1790b6 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -707,6 +707,7 @@ 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; |