[PATCH] drm/rockchip: vop2: fix suspend/resume

[Heiko Stübner]

Hi Sascha,

Am Montag, 17. April 2023, 11:42:15 CEST schrieb Sascha Hauer:
> During a suspend/resume cycle the VO power domain will be disabled and
> the VOP2 registers will reset to their default values. After that the
> cached register values will be out of sync and the read/modify/write
> operations we do on the window registers will result in bogus values
> written. Fix this by marking the regcache as dirty each time we disable
> the VOP2 and call regcache_sync() each time we enable it again. With
> this the VOP2 will show a picture after a suspend/resume cycle whereas
> without this the screen stays dark.
> 
> Fixes: 604be85547ce4 ("drm/rockchip: Add VOP2 driver")
> Cc: stable at vger.kernel.org
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>

somehow we overlapped with this v2 and me applying the original one [0]
to drm-misc. With drm-misc being a shared tree there is also no way back.

So if this v2 is better suited, could do a follow-up patch instead - on
top of your original one?

Thanks
Heiko



[0] https://cgit.freedesktop.org/drm/drm-misc/commit/?h=drm-misc-fixes&id=afa965a45e01e541cdbe5c8018226eff117610f0

> ---
> 
> Changes since v1:
> - Use regcache_mark_dirty()/regcache_sync() instead of regmap_reinit_cache()
> 
>  drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> index ba3b817895091..293c228a83f90 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> @@ -839,6 +839,8 @@ static void vop2_enable(struct vop2 *vop2)
>  		return;
>  	}
>  
> +	regcache_sync(vop2->map);
> +
>  	if (vop2->data->soc_id == 3566)
>  		vop2_writel(vop2, RK3568_OTP_WIN_EN, 1);
>  
> @@ -867,6 +869,8 @@ static void vop2_disable(struct vop2 *vop2)
>  
>  	pm_runtime_put_sync(vop2->dev);
>  
> +	regcache_mark_dirty(vop2->map);
> +
>  	clk_disable_unprepare(vop2->aclk);
>  	clk_disable_unprepare(vop2->hclk);
>  }
>