[PATCH v3 3/5] drm: xlnx: zynqmp_dpsub: Clear status register ASAP

From: Anatoliy Klymenko
Date: Tue Jan 23 2024 - 21:55:57 EST


Clear status register as soon as we read it.

Addressing comments from
https://lore.kernel.org/dri-devel/beb551c7-bb7e-4cd0-b166-e9aad90c4620@xxxxxxxxxxxxxxxx/

Signed-off-by: Anatoliy Klymenko <anatoliy.klymenko@xxxxxxx>
---
drivers/gpu/drm/xlnx/zynqmp_dp.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/xlnx/zynqmp_dp.c b/drivers/gpu/drm/xlnx/zynqmp_dp.c
index d60b7431603f..5a3335e1fffa 100644
--- a/drivers/gpu/drm/xlnx/zynqmp_dp.c
+++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c
@@ -1624,6 +1624,8 @@ static irqreturn_t zynqmp_dp_irq_handler(int irq, void *data)
u32 status, mask;

status = zynqmp_dp_read(dp, ZYNQMP_DP_INT_STATUS);
+ /* clear status register as soon as we read it */
+ zynqmp_dp_write(dp, ZYNQMP_DP_INT_STATUS, status);
mask = zynqmp_dp_read(dp, ZYNQMP_DP_INT_MASK);
if (!(status & ~mask))
return IRQ_NONE;
@@ -1634,8 +1636,6 @@ static irqreturn_t zynqmp_dp_irq_handler(int irq, void *data)
if (status & ZYNQMP_DP_INT_CHBUF_OVERFLW_MASK)
dev_dbg_ratelimited(dp->dev, "overflow interrupt\n");

- zynqmp_dp_write(dp, ZYNQMP_DP_INT_STATUS, status);
-
if (status & ZYNQMP_DP_INT_VBLANK_START)
zynqmp_dpsub_drm_handle_vblank(dp->dpsub);

--
2.25.1