[PATCH 33/36] drm/i915: Remove the extraneous irqreturn_t from gen8 sub handlers

[Chris Wilson]

We know whether or not the irq was intended for us by simpling
inspecting the GEN8_MASTER_IRQ. If that wasn't signaled, the irq was
spurious and that is when, and only when, we should report to the core
that we didn't handle the irq.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_irq.c | 51 +++++++++++++----------------------------
 1 file changed, 16 insertions(+), 35 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index af573328e9a6..24c0c79f7cfd 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -1374,52 +1374,43 @@ gen8_cs_irq_handler(struct intel_engine_cs *engine, u32 iir, int test_shift)
 		tasklet_hi_schedule(&engine->irq_tasklet);
 }
 
-static irqreturn_t gen8_gt_irq_ack(struct drm_i915_private *dev_priv,
-				   u32 master_ctl,
-				   u32 gt_iir[4])
+static void gen8_gt_irq_ack(struct drm_i915_private *dev_priv,
+			    u32 master_ctl, u32 gt_iir[4])
 {
-	irqreturn_t ret = IRQ_NONE;
-
 	if (master_ctl & (GEN8_GT_RCS_IRQ | GEN8_GT_BCS_IRQ)) {
 		gt_iir[0] = I915_READ_FW(GEN8_GT_IIR(0));
-		if (gt_iir[0]) {
+		if (likely(gt_iir[0]))
 			I915_WRITE_FW(GEN8_GT_IIR(0), gt_iir[0]);
-			ret = IRQ_HANDLED;
-		} else
+		else
 			DRM_ERROR("The master control interrupt lied (GT0)!\n");
 	}
 
 	if (master_ctl & (GEN8_GT_VCS1_IRQ | GEN8_GT_VCS2_IRQ)) {
 		gt_iir[1] = I915_READ_FW(GEN8_GT_IIR(1));
-		if (gt_iir[1]) {
+		if (likely(gt_iir[1]))
 			I915_WRITE_FW(GEN8_GT_IIR(1), gt_iir[1]);
-			ret = IRQ_HANDLED;
-		} else
+		else
 			DRM_ERROR("The master control interrupt lied (GT1)!\n");
 	}
 
 	if (master_ctl & GEN8_GT_VECS_IRQ) {
 		gt_iir[3] = I915_READ_FW(GEN8_GT_IIR(3));
-		if (gt_iir[3]) {
+		if (likely(gt_iir[3]))
 			I915_WRITE_FW(GEN8_GT_IIR(3), gt_iir[3]);
-			ret = IRQ_HANDLED;
-		} else
+		else
 			DRM_ERROR("The master control interrupt lied (GT3)!\n");
 	}
 
 	if (master_ctl & (GEN8_GT_PM_IRQ | GEN8_GT_GUC_IRQ)) {
 		gt_iir[2] = I915_READ_FW(GEN8_GT_IIR(2));
-		if (gt_iir[2] & (dev_priv->pm_rps_events |
-				 dev_priv->pm_guc_events)) {
+		if (likely(gt_iir[2] & (dev_priv->pm_rps_events |
+					dev_priv->pm_guc_events)))
 			I915_WRITE_FW(GEN8_GT_IIR(2),
 				      gt_iir[2] & (dev_priv->pm_rps_events |
 						   dev_priv->pm_guc_events));
-			ret = IRQ_HANDLED;
-		} else
+		else
 			DRM_ERROR("The master control interrupt lied (PM)!\n");
 	}
-
-	return ret;
 }
 
 static void gen8_gt_irq_handler(struct drm_i915_private *dev_priv,
@@ -2460,10 +2451,9 @@ static void bxt_hpd_irq_handler(struct drm_i915_private *dev_priv,
 	intel_hpd_irq_handler(dev_priv, pin_mask, long_mask);
 }
 
-static irqreturn_t
+static void
 gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 {
-	irqreturn_t ret = IRQ_NONE;
 	u32 iir;
 	enum pipe pipe;
 
@@ -2471,13 +2461,11 @@ gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 		iir = I915_READ(GEN8_DE_MISC_IIR);
 		if (iir) {
 			I915_WRITE(GEN8_DE_MISC_IIR, iir);
-			ret = IRQ_HANDLED;
 			if (iir & GEN8_DE_MISC_GSE)
 				intel_opregion_asle_intr(dev_priv);
 			else
 				DRM_ERROR("Unexpected DE Misc interrupt\n");
-		}
-		else
+		} else
 			DRM_ERROR("The master control interrupt lied (DE MISC)!\n");
 	}
 
@@ -2488,7 +2476,6 @@ gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 			bool found = false;
 
 			I915_WRITE(GEN8_DE_PORT_IIR, iir);
-			ret = IRQ_HANDLED;
 
 			tmp_mask = GEN8_AUX_CHANNEL_A;
 			if (INTEL_INFO(dev_priv)->gen >= 9)
@@ -2541,7 +2528,6 @@ gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 			continue;
 		}
 
-		ret = IRQ_HANDLED;
 		I915_WRITE(GEN8_DE_PIPE_IIR(pipe), iir);
 
 		if (iir & GEN8_PIPE_VBLANK &&
@@ -2585,8 +2571,6 @@ gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 		iir = I915_READ(SDEIIR);
 		if (iir) {
 			I915_WRITE(SDEIIR, iir);
-			ret = IRQ_HANDLED;
-
 			if (HAS_PCH_SPT(dev_priv) || HAS_PCH_KBP(dev_priv))
 				spt_irq_handler(dev_priv, iir);
 			else
@@ -2599,8 +2583,6 @@ gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 			DRM_DEBUG_DRIVER("The master control interrupt lied (SDE)!\n");
 		}
 	}
-
-	return ret;
 }
 
 #define GEN8_GT_IRQ_BITS (GEN8_GT_RCS_IRQ | GEN8_GT_BCS_IRQ | \
@@ -2611,7 +2593,6 @@ static irqreturn_t gen8_irq_handler(int irq, void *arg)
 {
 	struct drm_i915_private *dev_priv = arg;
 	u32 master_ctl, gt_iir[4];
-	irqreturn_t ret = IRQ_NONE;
 
 	if (!intel_irqs_enabled(dev_priv))
 		return IRQ_NONE;
@@ -2624,11 +2605,11 @@ static irqreturn_t gen8_irq_handler(int irq, void *arg)
 
 	/* Find, clear, then process each source of interrupt */
 	if (master_ctl & GEN8_GT_IRQ_BITS)
-		ret |= gen8_gt_irq_ack(dev_priv, master_ctl, gt_iir);
+		gen8_gt_irq_ack(dev_priv, master_ctl, gt_iir);
 
 	if (master_ctl & ~GEN8_GT_IRQ_BITS) {
 		disable_rpm_wakeref_asserts(dev_priv);
-		ret |= gen8_de_irq_handler(dev_priv, master_ctl);
+		gen8_de_irq_handler(dev_priv, master_ctl);
 		enable_rpm_wakeref_asserts(dev_priv);
 	}
 
@@ -2637,7 +2618,7 @@ static irqreturn_t gen8_irq_handler(int irq, void *arg)
 	if (master_ctl & GEN8_GT_IRQ_BITS)
 		gen8_gt_irq_handler(dev_priv, master_ctl, gt_iir);
 
-	return ret;
+	return IRQ_HANDLED;
 }
 
 /**
-- 
2.11.0