[PATCH 07/14] drm/amd/display: Initialize DSC PPS variables to 0

[Kazlauskas, Nicholas]

On 8/19/19 11:50 AM, David Francis wrote:
> For DSC MST, sometimes monitors would break out
> in full-screen static. The issue traced back to the
> PPS generation code, where these variables were being used
> uninitialized and were picking up garbage.
> 
> memset to 0 to avoid this
> 
> Signed-off-by: David Francis <David.Francis at amd.com>

Patches 1-5 and 7 are:

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas at amd.com>

> ---
>   drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c | 3 +++
>   drivers/gpu/drm/amd/display/dc/dcn20/dcn20_dsc.c   | 3 +++
>   2 files changed, 6 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c
> index 35c5467e60e8..619ac48edd05 100644
> --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c
> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c
> @@ -491,6 +491,9 @@ bool dp_set_dsc_pps_sdp(struct pipe_ctx *pipe_ctx, bool enable)
>   		struct dsc_config dsc_cfg;
>   		uint8_t dsc_packed_pps[128];
>   
> +		memset(&dsc_cfg, 0, sizeof(dsc_cfg));
> +		memset(dsc_packed_pps, 0, 128);
> +
>   		/* Enable DSC hw block */
>   		dsc_cfg.pic_width = stream->timing.h_addressable + stream->timing.h_border_left + stream->timing.h_border_right;
>   		dsc_cfg.pic_height = stream->timing.v_addressable + stream->timing.v_border_top + stream->timing.v_border_bottom;
> diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_dsc.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_dsc.c
> index 379c9e4ac63b..16debe6d89f2 100644
> --- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_dsc.c
> +++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_dsc.c
> @@ -207,6 +207,9 @@ static bool dsc2_get_packed_pps(struct display_stream_compressor *dsc, const str
>   	struct dsc_reg_values dsc_reg_vals;
>   	struct dsc_optc_config dsc_optc_cfg;
>   
> +	memset(&dsc_reg_vals, 0, sizeof(dsc_reg_vals));
> +	memset(&dsc_optc_cfg, 0, sizeof(dsc_optc_cfg));
> +
>   	DC_LOG_DSC("Getting packed DSC PPS for DSC Config:");
>   	dsc_config_log(dsc, dsc_cfg);
>   	DC_LOG_DSC("DSC Picture Parameter Set (PPS):");
>