[v8] Add display driver for MT8188 VDOSYS1

[PATCH v8 21/23] drm/mediatek: Fix underrun in VDO1 when switches off the layer

Posted by Hsiao Chien Sung 2 years, 3 months ago

Do not reset Merge while using CMDQ because reset API doesn't
wait for frame done event as CMDQ does and could lead to
underrun when the layer is switching off.

Fixes: aaf94f7c3ae6 ("drm/mediatek: Add display merge async reset control")

Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com>
---
 drivers/gpu/drm/mediatek/mtk_disp_merge.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_merge.c b/drivers/gpu/drm/mediatek/mtk_disp_merge.c
index fd14a59bc951..c19fb1836034 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_merge.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_merge.c
@@ -104,7 +104,7 @@ void mtk_merge_stop_cmdq(struct device *dev, struct cmdq_pkt *cmdq_pkt)
 	mtk_ddp_write(cmdq_pkt, 0, &priv->cmdq_reg, priv->regs,
 		      DISP_REG_MERGE_CTRL);
 
-	if (priv->async_clk)
+	if (!cmdq_pkt && priv->async_clk)
 		reset_control_reset(priv->reset_ctl);
 }
 
-- 
2.18.0

Re: [PATCH v8 21/23] drm/mediatek: Fix underrun in VDO1 when switches off the layer

Posted by AngeloGioacchino Del Regno 2 years, 3 months ago

Il 16/10/23 12:40, Hsiao Chien Sung ha scritto:
> Do not reset Merge while using CMDQ because reset API doesn't
> wait for frame done event as CMDQ does and could lead to
> underrun when the layer is switching off.
> 
> Fixes: aaf94f7c3ae6 ("drm/mediatek: Add display merge async reset control")
> 
> Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

Re: [PATCH v8 21/23] drm/mediatek: Fix underrun in VDO1 when switches off the layer

Posted by CK Hu (胡俊光) 2 years, 3 months ago

Hi, Hsiao-chien:

On Mon, 2023-10-16 at 18:40 +0800, Hsiao Chien Sung wrote:
> Do not reset Merge while using CMDQ because reset API doesn't
> wait for frame done event as CMDQ does and could lead to
> underrun when the layer is switching off.

Reviewed-by: CK Hu <ck.hu@mediatek.com>

> 
> Fixes: aaf94f7c3ae6 ("drm/mediatek: Add display merge async reset
> control")
> 
> Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_disp_merge.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> b/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> index fd14a59bc951..c19fb1836034 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> @@ -104,7 +104,7 @@ void mtk_merge_stop_cmdq(struct device *dev,
> struct cmdq_pkt *cmdq_pkt)
>  	mtk_ddp_write(cmdq_pkt, 0, &priv->cmdq_reg, priv->regs,
>  		      DISP_REG_MERGE_CTRL);
>  
> -	if (priv->async_clk)
> +	if (!cmdq_pkt && priv->async_clk)
>  		reset_control_reset(priv->reset_ctl);
>  }
>