RE: [PATCH] drm: xlnx: dp: Reset DisplayPort IP

From: Sagar, Vishal
Date: Fri Feb 16 2024 - 11:55:22 EST


[AMD Official Use Only - General]

Hi Rohit,

Thanks for the patch.

> -----Original Message-----
> From: dri-devel <dri-devel-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of
> Rohit Visavalia
> Sent: Friday, February 16, 2024 1:41 PM
> To: gregkh@xxxxxxxxxxxxxxxxxxx; laurent.pinchart@xxxxxxxxxxxxxxxx;
> maarten.lankhorst@xxxxxxxxxxxxxxx; mripard@xxxxxxxxxx;
> tzimmermann@xxxxxxx; airlied@xxxxxxxxx; daniel@xxxxxxxx; Simek, Michal
> <michal.simek@xxxxxxx>; dri-devel@xxxxxxxxxxxxxxxxxxxxx; linux-arm-
> kernel@xxxxxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Subject: [PATCH] drm: xlnx: dp: Reset DisplayPort IP
>
> Assert DisplayPort reset signal before deasserting,
> it is to clear out any registers programmed before booting kernel.
>
> Signed-off-by: Rohit Visavalia <rohit.visavalia@xxxxxxx>
> ---
> drivers/gpu/drm/xlnx/zynqmp_dp.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/gpu/drm/xlnx/zynqmp_dp.c
> b/drivers/gpu/drm/xlnx/zynqmp_dp.c
> index 1846c4971fd8..5a40aa1d4283 100644
> --- a/drivers/gpu/drm/xlnx/zynqmp_dp.c
> +++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c
> @@ -1714,6 +1714,10 @@ int zynqmp_dp_probe(struct zynqmp_dpsub
> *dpsub)
> goto err_free;
> }
>
> + ret = zynqmp_dp_reset(dp, true);
> + if (ret < 0)
> + return ret;
> +
> ret = zynqmp_dp_reset(dp, false);
> if (ret < 0)
> goto err_free;
> --
> 2.25.1

This looks good to me.

Reviewed-by: Vishal Sagar<vishal.sagar@xxxxxxx>

Regards
Vishal Sagar