From 96d91d77d644450ef2979cb5c3f998f6f241bd6b Mon Sep 17 00:00:00 2001
From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Date: Fri, 18 Jun 2021 01:20:24 +0300
Subject: drm/msm/dpu: don't clear IRQ register twice
Git-commit: 6087623e7c904de4c8ff48f78dc70cc05ddb8e40
Patch-mainline: v5.16-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

We already clear the IRQ status register before processing IRQs, so do
not clear the register again. Especially do not clear the IRQ status
_after_ processing the IRQ as this way we can loose the event.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
Link: https://lore.kernel.org/r/20210617222029.463045-3-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 .../gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.c   | 17 -----------------
 1 file changed, 17 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.c
index 2437b0c7c073..28e9b0d448db 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.c
@@ -120,21 +120,6 @@ static const struct dpu_intr_reg dpu_intr_set[] = {
 #define DPU_IRQ_REG(irq_idx)	(irq_idx / 32)
 #define DPU_IRQ_MASK(irq_idx)	(BIT(irq_idx % 32))
 
-static void dpu_hw_intr_clear_intr_status_nolock(struct dpu_hw_intr *intr,
-		int irq_idx)
-{
-	int reg_idx;
-
-	if (!intr)
-		return;
-
-	reg_idx = DPU_IRQ_REG(irq_idx);
-	DPU_REG_WRITE(&intr->hw, dpu_intr_set[reg_idx].clr_off, DPU_IRQ_MASK(irq_idx));
-
-	/* ensure register writes go through */
-	wmb();
-}
-
 /**
  * dpu_core_irq_callback_handler - dispatch core interrupts
  * @arg:		private data of callback handler
@@ -203,8 +188,6 @@ irqreturn_t dpu_core_irq(struct dpu_kms *dpu_kms)
 
 			dpu_core_irq_callback_handler(dpu_kms, irq_idx);
 
-			dpu_hw_intr_clear_intr_status_nolock(intr, irq_idx);
-
 			/*
 			 * When callback finish, clear the irq_status
 			 * with the matching mask. Once irq_status
-- 
2.38.1