lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

i915: Protect vblank IRQ reg access with spinlock

Browse Source 
This uses the same spinlock as the user_irq code as it shares the same
register, ensuring that interrupt registers are updated atomically.

Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Keith Packard
2008-10-16 11:31:38 -07:00
committed by Dave Airlie
parent 4b40893918
commit e9d21d7f5a
1 changed files with 40 additions and 29 deletions
Download Patch File Download Diff File Expand all files Collapse all files

37
drivers/gpu/drm/i915/i915_irq.c
View File

@@ -481,22 +481,24 @@ static int i915_emit_irq(struct drm_device * dev)
void i915_user_irq_get(struct drm_device *dev) void i915_user_irq_get(struct drm_device *dev)
{ {
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private; drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
unsigned long irqflags;
spin_lock(&dev_priv->user_irq_lock); spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
if (dev->irq_enabled && (++dev_priv->user_irq_refcount == 1)) if (dev->irq_enabled && (++dev_priv->user_irq_refcount == 1))
i915_enable_irq(dev_priv, I915_USER_INTERRUPT); i915_enable_irq(dev_priv, I915_USER_INTERRUPT);
spin_unlock(&dev_priv->user_irq_lock); spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
} }
void i915_user_irq_put(struct drm_device *dev) void i915_user_irq_put(struct drm_device *dev)
{ {
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private; drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
unsigned long irqflags;
spin_lock(&dev_priv->user_irq_lock); spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
BUG_ON(dev->irq_enabled && dev_priv->user_irq_refcount <= 0); BUG_ON(dev->irq_enabled && dev_priv->user_irq_refcount <= 0);
if (dev->irq_enabled && (--dev_priv->user_irq_refcount == 0)) if (dev->irq_enabled && (--dev_priv->user_irq_refcount == 0))
i915_disable_irq(dev_priv, I915_USER_INTERRUPT); i915_disable_irq(dev_priv, I915_USER_INTERRUPT);
spin_unlock(&dev_priv->user_irq_lock); spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
} }
static int i915_wait_irq(struct drm_device * dev, int irq_nr) static int i915_wait_irq(struct drm_device * dev, int irq_nr)
@@ -584,23 +586,25 @@ int i915_enable_vblank(struct drm_device *dev, int plane)
int pipe = i915_get_pipe(dev, plane); int pipe = i915_get_pipe(dev, plane);
u32 pipestat_reg = 0; u32 pipestat_reg = 0;
u32 pipestat; u32 pipestat;
u32 interrupt = 0;
unsigned long irqflags;
switch (pipe) { switch (pipe) {
case 0: case 0:
pipestat_reg = PIPEASTAT; pipestat_reg = PIPEASTAT;
i915_enable_irq(dev_priv, I915_DISPLAY_PIPE_A_EVENT_INTERRUPT); interrupt = I915_DISPLAY_PIPE_A_EVENT_INTERRUPT;
break; break;
case 1: case 1:
pipestat_reg = PIPEBSTAT; pipestat_reg = PIPEBSTAT;
i915_enable_irq(dev_priv, I915_DISPLAY_PIPE_B_EVENT_INTERRUPT); interrupt = I915_DISPLAY_PIPE_B_EVENT_INTERRUPT;
break; break;
default: default:
DRM_ERROR("tried to enable vblank on non-existent pipe %d\n", DRM_ERROR("tried to enable vblank on non-existent pipe %d\n",
pipe); pipe);
break; return 0;
} }
if (pipestat_reg) { spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
pipestat = I915_READ(pipestat_reg); pipestat = I915_READ(pipestat_reg);
if (IS_I965G(dev)) if (IS_I965G(dev))
pipestat |= PIPE_START_VBLANK_INTERRUPT_ENABLE; pipestat |= PIPE_START_VBLANK_INTERRUPT_ENABLE;
@@ -610,7 +614,9 @@ int i915_enable_vblank(struct drm_device *dev, int plane)
pipestat |= (PIPE_START_VBLANK_INTERRUPT_STATUS | pipestat |= (PIPE_START_VBLANK_INTERRUPT_STATUS |
PIPE_VBLANK_INTERRUPT_STATUS); PIPE_VBLANK_INTERRUPT_STATUS);
I915_WRITE(pipestat_reg, pipestat); I915_WRITE(pipestat_reg, pipestat);
} (void) I915_READ(pipestat_reg); /* Posting read */
i915_enable_irq(dev_priv, interrupt);
spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
return 0; return 0;
} }
@@ -621,23 +627,27 @@ void i915_disable_vblank(struct drm_device *dev, int plane)
int pipe = i915_get_pipe(dev, plane); int pipe = i915_get_pipe(dev, plane);
u32 pipestat_reg = 0; u32 pipestat_reg = 0;
u32 pipestat; u32 pipestat;
u32 interrupt = 0;
unsigned long irqflags;
switch (pipe) { switch (pipe) {
case 0: case 0:
pipestat_reg = PIPEASTAT; pipestat_reg = PIPEASTAT;
i915_disable_irq(dev_priv, I915_DISPLAY_PIPE_A_EVENT_INTERRUPT); interrupt = I915_DISPLAY_PIPE_A_EVENT_INTERRUPT;
break; break;
case 1: case 1:
pipestat_reg = PIPEBSTAT; pipestat_reg = PIPEBSTAT;
i915_disable_irq(dev_priv, I915_DISPLAY_PIPE_B_EVENT_INTERRUPT); interrupt = I915_DISPLAY_PIPE_B_EVENT_INTERRUPT;
break; break;
default: default:
DRM_ERROR("tried to disable vblank on non-existent pipe %d\n", DRM_ERROR("tried to disable vblank on non-existent pipe %d\n",
pipe); pipe);
return;
break; break;
} }
if (pipestat_reg) { spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
i915_disable_irq(dev_priv, interrupt);
pipestat = I915_READ(pipestat_reg); pipestat = I915_READ(pipestat_reg);
pipestat &= ~(PIPE_START_VBLANK_INTERRUPT_ENABLE | pipestat &= ~(PIPE_START_VBLANK_INTERRUPT_ENABLE |
PIPE_VBLANK_INTERRUPT_ENABLE); PIPE_VBLANK_INTERRUPT_ENABLE);
@@ -645,7 +655,8 @@ void i915_disable_vblank(struct drm_device *dev, int plane)
pipestat |= (PIPE_START_VBLANK_INTERRUPT_STATUS | pipestat |= (PIPE_START_VBLANK_INTERRUPT_STATUS |
PIPE_VBLANK_INTERRUPT_STATUS); PIPE_VBLANK_INTERRUPT_STATUS);
I915_WRITE(pipestat_reg, pipestat); I915_WRITE(pipestat_reg, pipestat);
} (void) I915_READ(pipestat_reg); /* Posting read */
spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
} }
/* Set the vblank monitor pipe /* Set the vblank monitor pipe