From: Mario Limonciello <mario.limonciello@amd.com>
To: Alex Hung <alex.hung@amd.com>, amd-gfx@lists.freedesktop.org
Cc: Harry Wentland <harry.wentland@amd.com>,
Leo Li <sunpeng.li@amd.com>,
Aurabindo Pillai <aurabindo.pillai@amd.com>,
Roman Li <roman.li@amd.com>, Wayne Lin <wayne.lin@amd.com>,
Tom Chung <chiahsuan.chung@amd.com>,
Fangzhi Zuo <jerry.zuo@amd.com>,
Dan Wheeler <daniel.wheeler@amd.com>, Ray Wu <Ray.Wu@amd.com>,
Ivan Lipski <ivan.lipski@amd.com>,
Relja Vojvodic <rvojvodi@amd.com>,
Alex Deucher <alexander.deucher@amd.com>,
stable@vger.kernel.org, Chris Park <chris.park@amd.com>,
Wenjing Liu <wenjing.liu@amd.com>
Subject: Re: [PATCH 23/26] drm/amd/display: Correct DSC padding accounting
Date: Thu, 20 Nov 2025 12:33:21 -0600 [thread overview]
Message-ID: <49c24aad-90cb-4d87-afe2-1a65d2d85e80@amd.com> (raw)
In-Reply-To: <20251120181527.317107-24-alex.hung@amd.com>
On 11/20/2025 12:03 PM, Alex Hung wrote:
> From: Relja Vojvodic <rvojvodi@amd.com>
>
> [WHY]
> - After the addition of all OVT patches, DSC padding was being accounted
> for multiple times, effectively doubling the padding
Can you double check when the OVT patches were submitted and if they
were CC @stable? If not; I think the stable tag should be dropped on
this patch.
> - This caused compliance failures or corruption
>
> [HOW]
> - Add padding to DSC pic width when required by HW, and do not re-add
> when calculating reg values
> - Do not add padding when computing PPS values, and instead track padding
> separately to add when calculating slice width values
>
> Cc: Mario Limonciello <mario.limonciello@amd.com>
> Cc: Alex Deucher <alexander.deucher@amd.com>
> Cc: stable@vger.kernel.org
> Reviewed-by: Chris Park <chris.park@amd.com>
> Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
> Signed-off-by: Relja Vojvodic <rvojvodi@amd.com>
> Signed-off-by: Alex Hung <alex.hung@amd.com>
> ---
> drivers/gpu/drm/amd/display/dc/hwss/dcn314/dcn314_hwseq.c | 2 +-
> drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c | 2 +-
> drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c | 2 +-
> drivers/gpu/drm/amd/display/dc/link/link_dpms.c | 3 ++-
> .../gpu/drm/amd/display/dc/resource/dcn20/dcn20_resource.c | 6 +++---
> 5 files changed, 8 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn314/dcn314_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn314/dcn314_hwseq.c
> index 4ee6ed610de0..3e239124c17d 100644
> --- a/drivers/gpu/drm/amd/display/dc/hwss/dcn314/dcn314_hwseq.c
> +++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn314/dcn314_hwseq.c
> @@ -108,7 +108,7 @@ static void update_dsc_on_stream(struct pipe_ctx *pipe_ctx, bool enable)
> dsc_cfg.dc_dsc_cfg = stream->timing.dsc_cfg;
> ASSERT(dsc_cfg.dc_dsc_cfg.num_slices_h % opp_cnt == 0);
> dsc_cfg.dc_dsc_cfg.num_slices_h /= opp_cnt;
> - dsc_cfg.dsc_padding = pipe_ctx->dsc_padding_params.dsc_hactive_padding;
> + dsc_cfg.dsc_padding = 0;
>
> dsc->funcs->dsc_set_config(dsc, &dsc_cfg, &dsc_optc_cfg);
> dsc->funcs->dsc_enable(dsc, pipe_ctx->stream_res.opp->inst);
> diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c
> index bf19ba65d09a..b213a2ac827a 100644
> --- a/drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c
> +++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c
> @@ -1061,7 +1061,7 @@ void dcn32_update_dsc_on_stream(struct pipe_ctx *pipe_ctx, bool enable)
> dsc_cfg.dc_dsc_cfg = stream->timing.dsc_cfg;
> ASSERT(dsc_cfg.dc_dsc_cfg.num_slices_h % opp_cnt == 0);
> dsc_cfg.dc_dsc_cfg.num_slices_h /= opp_cnt;
> - dsc_cfg.dsc_padding = pipe_ctx->dsc_padding_params.dsc_hactive_padding;
> + dsc_cfg.dsc_padding = 0;
>
> if (should_use_dto_dscclk)
> dccg->funcs->set_dto_dscclk(dccg, dsc->inst, dsc_cfg.dc_dsc_cfg.num_slices_h);
> diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c
> index 7aa0f452e8f7..cb2dfd34b5e2 100644
> --- a/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c
> +++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c
> @@ -364,7 +364,7 @@ static void update_dsc_on_stream(struct pipe_ctx *pipe_ctx, bool enable)
> dsc_cfg.dc_dsc_cfg = stream->timing.dsc_cfg;
> ASSERT(dsc_cfg.dc_dsc_cfg.num_slices_h % opp_cnt == 0);
> dsc_cfg.dc_dsc_cfg.num_slices_h /= opp_cnt;
> - dsc_cfg.dsc_padding = pipe_ctx->dsc_padding_params.dsc_hactive_padding;
> + dsc_cfg.dsc_padding = 0;
>
> dsc->funcs->dsc_set_config(dsc, &dsc_cfg, &dsc_optc_cfg);
> dsc->funcs->dsc_enable(dsc, pipe_ctx->stream_res.opp->inst);
> diff --git a/drivers/gpu/drm/amd/display/dc/link/link_dpms.c b/drivers/gpu/drm/amd/display/dc/link/link_dpms.c
> index 1b1ce3839922..77e049917c4d 100644
> --- a/drivers/gpu/drm/amd/display/dc/link/link_dpms.c
> +++ b/drivers/gpu/drm/amd/display/dc/link/link_dpms.c
> @@ -841,7 +841,7 @@ void link_set_dsc_on_stream(struct pipe_ctx *pipe_ctx, bool enable)
> dsc_cfg.dc_dsc_cfg = stream->timing.dsc_cfg;
> ASSERT(dsc_cfg.dc_dsc_cfg.num_slices_h % opp_cnt == 0);
> dsc_cfg.dc_dsc_cfg.num_slices_h /= opp_cnt;
> - dsc_cfg.dsc_padding = pipe_ctx->dsc_padding_params.dsc_hactive_padding;
> + dsc_cfg.dsc_padding = 0;
>
> if (should_use_dto_dscclk)
> dccg->funcs->set_dto_dscclk(dccg, dsc->inst, dsc_cfg.dc_dsc_cfg.num_slices_h);
> @@ -857,6 +857,7 @@ void link_set_dsc_on_stream(struct pipe_ctx *pipe_ctx, bool enable)
> }
> dsc_cfg.dc_dsc_cfg.num_slices_h *= opp_cnt;
> dsc_cfg.pic_width *= opp_cnt;
> + dsc_cfg.dsc_padding = pipe_ctx->dsc_padding_params.dsc_hactive_padding;
>
> optc_dsc_mode = dsc_optc_cfg.is_pixel_format_444 ? OPTC_DSC_ENABLED_444 : OPTC_DSC_ENABLED_NATIVE_SUBSAMPLED;
>
> diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn20/dcn20_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn20/dcn20_resource.c
> index 6679c1a14f2f..8d10aac9c510 100644
> --- a/drivers/gpu/drm/amd/display/dc/resource/dcn20/dcn20_resource.c
> +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn20/dcn20_resource.c
> @@ -1660,8 +1660,8 @@ bool dcn20_validate_dsc(struct dc *dc, struct dc_state *new_ctx)
> if (pipe_ctx->top_pipe || pipe_ctx->prev_odm_pipe || !stream || !stream->timing.flags.DSC)
> continue;
>
> - dsc_cfg.pic_width = (stream->timing.h_addressable + stream->timing.h_border_left
> - + stream->timing.h_border_right) / opp_cnt;
> + dsc_cfg.pic_width = (stream->timing.h_addressable + pipe_ctx->dsc_padding_params.dsc_hactive_padding
> + + stream->timing.h_border_left + stream->timing.h_border_right) / opp_cnt;
> dsc_cfg.pic_height = stream->timing.v_addressable + stream->timing.v_border_top
> + stream->timing.v_border_bottom;
> dsc_cfg.pixel_encoding = stream->timing.pixel_encoding;
> @@ -1669,7 +1669,7 @@ bool dcn20_validate_dsc(struct dc *dc, struct dc_state *new_ctx)
> dsc_cfg.is_odm = pipe_ctx->next_odm_pipe ? true : false;
> dsc_cfg.dc_dsc_cfg = stream->timing.dsc_cfg;
> dsc_cfg.dc_dsc_cfg.num_slices_h /= opp_cnt;
> - dsc_cfg.dsc_padding = pipe_ctx->dsc_padding_params.dsc_hactive_padding;
> + dsc_cfg.dsc_padding = 0;
>
> if (!pipe_ctx->stream_res.dsc->funcs->dsc_validate_stream(pipe_ctx->stream_res.dsc, &dsc_cfg))
> return false;
next prev parent reply other threads:[~2025-11-20 18:33 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20251120181527.317107-1-alex.hung@amd.com>
2025-11-20 18:02 ` [PATCH 01/26] drm/amd/display: Check NULL before accessing Alex Hung
2025-11-20 18:03 ` [PATCH 10/26] drm/amd/display: Don't change brightness for disabled connectors Alex Hung
2025-11-20 18:03 ` [PATCH 15/26] drm/amd/display: Increase EDID read retries Alex Hung
2025-11-20 18:03 ` [PATCH 19/26] drm/amd/display: Add cursor offload abort to the new HWSS path Alex Hung
2025-11-20 18:03 ` [PATCH 23/26] drm/amd/display: Correct DSC padding accounting Alex Hung
2025-11-20 18:33 ` Mario Limonciello [this message]
2025-11-20 18:35 ` Alex Hung
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