drm/i915: Add for_each_pipe_masked()

for_each_pipe_masked() can be used to iterate over the pipes
included in the user provided pipe mask. Removes a few lines of
duplicated code.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455907651-16397-2-git-send-email-ville.syrjala@linux.intel.comReviewed-by: Imre Deak <imre.deak@intel.com>

drivers/gpu/drm/i915/i915_drv.h

@@ -261,6 +261,9 @@ struct i915_hotplug {
 
 #define for_each_pipe(__dev_priv, __p) \
 	for ((__p) = 0; (__p) < INTEL_INFO(__dev_priv)->num_pipes; (__p)++)
+#define for_each_pipe_masked(__dev_priv, __p, __mask) \
+	for ((__p) = 0; (__p) < INTEL_INFO(__dev_priv)->num_pipes; (__p)++) \
+		for_each_if ((__mask) & (1 << (__p)))
 #define for_each_plane(__dev_priv, __pipe, __p)				\
 	for ((__p) = 0;							\
 	     (__p) < INTEL_INFO(__dev_priv)->num_sprites[(__pipe)] + 1;	\

drivers/gpu/drm/i915/i915_irq.c

@@ -3349,33 +3349,24 @@ void gen8_irq_power_well_post_enable(struct drm_i915_private *dev_priv,
 				     unsigned int pipe_mask)
 {
 	uint32_t extra_ier = GEN8_PIPE_VBLANK | GEN8_PIPE_FIFO_UNDERRUN;
+	enum pipe pipe;
 
 	spin_lock_irq(&dev_priv->irq_lock);
-	if (pipe_mask & 1 << PIPE_A)
-		GEN8_IRQ_INIT_NDX(DE_PIPE, PIPE_A,
-				  dev_priv->de_irq_mask[PIPE_A],
-				  ~dev_priv->de_irq_mask[PIPE_A] | extra_ier);
-	if (pipe_mask & 1 << PIPE_B)
-		GEN8_IRQ_INIT_NDX(DE_PIPE, PIPE_B,
-				  dev_priv->de_irq_mask[PIPE_B],
-				  ~dev_priv->de_irq_mask[PIPE_B] | extra_ier);
-	if (pipe_mask & 1 << PIPE_C)
-		GEN8_IRQ_INIT_NDX(DE_PIPE, PIPE_C,
-				  dev_priv->de_irq_mask[PIPE_C],
-				  ~dev_priv->de_irq_mask[PIPE_C] | extra_ier);
+	for_each_pipe_masked(dev_priv, pipe, pipe_mask)
+		GEN8_IRQ_INIT_NDX(DE_PIPE, pipe,
+				  dev_priv->de_irq_mask[pipe],
+				  ~dev_priv->de_irq_mask[pipe] | extra_ier);
 	spin_unlock_irq(&dev_priv->irq_lock);
 }
 
 void gen8_irq_power_well_pre_disable(struct drm_i915_private *dev_priv,
 				     unsigned int pipe_mask)
 {
+	enum pipe pipe;
+
 	spin_lock_irq(&dev_priv->irq_lock);
-	if (pipe_mask & 1 << PIPE_A)
-		GEN8_IRQ_RESET_NDX(DE_PIPE, PIPE_A);
-	if (pipe_mask & 1 << PIPE_B)
-		GEN8_IRQ_RESET_NDX(DE_PIPE, PIPE_B);
-	if (pipe_mask & 1 << PIPE_C)
-		GEN8_IRQ_RESET_NDX(DE_PIPE, PIPE_C);
+	for_each_pipe_masked(dev_priv, pipe, pipe_mask)
+		GEN8_IRQ_RESET_NDX(DE_PIPE, pipe);
 	spin_unlock_irq(&dev_priv->irq_lock);
 
 	/* make sure we're done processing display irqs */