Clear status register as soon as we read it.

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

Signed-off-by: Anatoliy Klymenko <anatoliy.klymenko@amd.com>
---
 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

Hi Anatoliy,

Thank you for the patch.

On Tue, Jan 23, 2024 at 06:54:00PM -0800, Anatoliy Klymenko wrote:
> Clear status register as soon as we read it.
> 
> Addressing comments from
> https://lore.kernel.org/dri-devel/beb551c7-bb7e-4cd0-b166-e9aad90c4620@ideasonboard.com/
> 
> Signed-off-by: Anatoliy Klymenko <anatoliy.klymenko@amd.com>
> ---
>  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 */

I don't think a comment is strictly required, but I don't mind it.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> +	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);
>  

-- 
Regards,

Laurent Pinchart

On 24/01/2024 04:54, Anatoliy Klymenko wrote:
> Clear status register as soon as we read it.
> 
> Addressing comments from
> https://lore.kernel.org/dri-devel/beb551c7-bb7e-4cd0-b166-e9aad90c4620@ideasonboard.com/
> 
> Signed-off-by: Anatoliy Klymenko <anatoliy.klymenko@amd.com>
> ---
>   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);
>   

Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>

  Tomi