[PATCH] drm/amd/display: fix corruption with high refresh rates on DCN 3.0

[Rodrigo Siqueira Jordao]

On 7/16/24 11:33 AM, Alex Deucher wrote:
> This reverts commit bc87d666c05a13e6d4ae1ddce41fc43d2567b9a2 and the
> register changes from commit 6d4279cb99ac4f51d10409501d29969f687ac8dc.
> 
> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3478
> Cc: mikhail.v.gavrilov at gmail.com
> Cc: Rodrigo Siqueira <Rodrigo.Siqueira at amd.com>
> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
> ---
>   .../drm/amd/display/dc/optc/dcn10/dcn10_optc.c    | 15 +++------------
>   .../drm/amd/display/dc/optc/dcn20/dcn20_optc.c    | 10 ++++++++++
>   2 files changed, 13 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/optc/dcn10/dcn10_optc.c b/drivers/gpu/drm/amd/display/dc/optc/dcn10/dcn10_optc.c
> index 4f82146d94b1..f00d27b7c6fe 100644
> --- a/drivers/gpu/drm/amd/display/dc/optc/dcn10/dcn10_optc.c
> +++ b/drivers/gpu/drm/amd/display/dc/optc/dcn10/dcn10_optc.c
> @@ -950,19 +950,10 @@ void optc1_set_drr(
>   				OTG_FORCE_LOCK_ON_EVENT, 0,
>   				OTG_SET_V_TOTAL_MIN_MASK_EN, 0,
>   				OTG_SET_V_TOTAL_MIN_MASK, 0);
> -
> -		// Setup manual flow control for EOF via TRIG_A
> -		optc->funcs->setup_manual_trigger(optc);
> -
> -	} else {
> -		REG_UPDATE_4(OTG_V_TOTAL_CONTROL,
> -				OTG_SET_V_TOTAL_MIN_MASK, 0,
> -				OTG_V_TOTAL_MIN_SEL, 0,
> -				OTG_V_TOTAL_MAX_SEL, 0,
> -				OTG_FORCE_LOCK_ON_EVENT, 0);
> -
> -		optc->funcs->set_vtotal_min_max(optc, 0, 0);
>   	}
> +
> +	// Setup manual flow control for EOF via TRIG_A
> +	optc->funcs->setup_manual_trigger(optc);
>   }
>   
>   void optc1_set_vtotal_min_max(struct timing_generator *optc, int vtotal_min, int vtotal_max)
> diff --git a/drivers/gpu/drm/amd/display/dc/optc/dcn20/dcn20_optc.c b/drivers/gpu/drm/amd/display/dc/optc/dcn20/dcn20_optc.c
> index 43417cff2c9b..b4694985a40a 100644
> --- a/drivers/gpu/drm/amd/display/dc/optc/dcn20/dcn20_optc.c
> +++ b/drivers/gpu/drm/amd/display/dc/optc/dcn20/dcn20_optc.c
> @@ -453,6 +453,16 @@ void optc2_setup_manual_trigger(struct timing_generator *optc)
>   {
>   	struct optc *optc1 = DCN10TG_FROM_TG(optc);
>   
> +	/* Set the min/max selectors unconditionally so that
> +	 * DMCUB fw may change OTG timings when necessary
> +	 * TODO: Remove the w/a after fixing the issue in DMCUB firmware
> +	 */
> +	REG_UPDATE_4(OTG_V_TOTAL_CONTROL,
> +				 OTG_V_TOTAL_MIN_SEL, 1,
> +				 OTG_V_TOTAL_MAX_SEL, 1,
> +				 OTG_FORCE_LOCK_ON_EVENT, 0,
> +				 OTG_SET_V_TOTAL_MIN_MASK, (1 << 1)); /* TRIGA */
> +
>   	REG_SET_8(OTG_TRIGA_CNTL, 0,
>   			OTG_TRIGA_SOURCE_SELECT, 21,
>   			OTG_TRIGA_SOURCE_PIPE_SELECT, optc->inst,

(+Jay)

Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira at amd.com>