diff options
Diffstat (limited to 'drivers/gpu/drm')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_drv.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 59dc4817964..42388533708 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -1131,9 +1131,20 @@ static bool IS_DISPLAYREG(u32 reg) return true; } +static void +ilk_dummy_write(struct drm_i915_private *dev_priv) +{ + /* WaIssueDummyWriteToWakeupFromRC6: Issue a dummy write to wake up the + * chip from rc6 before touching it for real. MI_MODE is masked, hence + * harmless to write 0 into. */ + I915_WRITE_NOTRACE(MI_MODE, 0); +} + #define __i915_read(x, y) \ u##x i915_read##x(struct drm_i915_private *dev_priv, u32 reg) { \ u##x val = 0; \ + if (IS_GEN5(dev_priv->dev)) \ + ilk_dummy_write(dev_priv); \ if (NEEDS_FORCE_WAKE((dev_priv), (reg))) { \ unsigned long irqflags; \ spin_lock_irqsave(&dev_priv->gt_lock, irqflags); \ @@ -1165,6 +1176,8 @@ void i915_write##x(struct drm_i915_private *dev_priv, u32 reg, u##x val) { \ if (NEEDS_FORCE_WAKE((dev_priv), (reg))) { \ __fifo_ret = __gen6_gt_wait_for_fifo(dev_priv); \ } \ + if (IS_GEN5(dev_priv->dev)) \ + ilk_dummy_write(dev_priv); \ if (IS_VALLEYVIEW(dev_priv->dev) && IS_DISPLAYREG(reg)) { \ write##y(val, dev_priv->regs + reg + 0x180000); \ } else { \ |