The patch below does not apply to the 6.2-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.2.y git checkout FETCH_HEAD git cherry-pick -x 2792f98cdb1c8fa43bf4ee5ae00349b823a823b7 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2023051326-karma-ablaze-9a44@gregkh' --subject-prefix 'PATCH 6.2.y' HEAD^.. Possible dependencies: 2792f98cdb1c ("drm/amd/display: Take FEC Overhead into Timeslot Calculation") 54c7b715b5ef ("drm/amd/display: Add DSC Support for Synaptics Cascaded MST Hub") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 2792f98cdb1c8fa43bf4ee5ae00349b823a823b7 Mon Sep 17 00:00:00 2001 From: Fangzhi Zuo <Jerry.Zuo@xxxxxxx> Date: Tue, 28 Feb 2023 21:34:58 -0500 Subject: [PATCH] drm/amd/display: Take FEC Overhead into Timeslot Calculation 8b/10b encoding needs to add 3% fec overhead into the pbn. In the Synapcis Cascaded MST hub, the first stage MST branch device needs the information to determine the timeslot count for the second stage MST branch device. Missing this overhead will leads to insufficient timeslot allocation. Cc: stable@xxxxxxxxxxxxxxx Cc: Mario Limonciello <mario.limonciello@xxxxxxx> Reviewed-by: Hersen Wu <hersenxs.wu@xxxxxxx> Acked-by: Qingqing Zhuo <qingqing.zhuo@xxxxxxx> Signed-off-by: Fangzhi Zuo <Jerry.Zuo@xxxxxxx> Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c index 9241d48e9d98..6378352346c8 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c @@ -670,12 +670,25 @@ struct dsc_mst_fairness_params { struct amdgpu_dm_connector *aconnector; }; -static int kbps_to_peak_pbn(int kbps) +static uint16_t get_fec_overhead_multiplier(struct dc_link *dc_link) +{ + u8 link_coding_cap; + uint16_t fec_overhead_multiplier_x1000 = PBN_FEC_OVERHEAD_MULTIPLIER_8B_10B; + + link_coding_cap = dc_link_dp_mst_decide_link_encoding_format(dc_link); + if (link_coding_cap == DP_128b_132b_ENCODING) + fec_overhead_multiplier_x1000 = PBN_FEC_OVERHEAD_MULTIPLIER_128B_132B; + + return fec_overhead_multiplier_x1000; +} + +static int kbps_to_peak_pbn(int kbps, uint16_t fec_overhead_multiplier_x1000) { u64 peak_kbps = kbps; peak_kbps *= 1006; - peak_kbps = div_u64(peak_kbps, 1000); + peak_kbps *= fec_overhead_multiplier_x1000; + peak_kbps = div_u64(peak_kbps, 1000 * 1000); return (int) DIV64_U64_ROUND_UP(peak_kbps * 64, (54 * 8 * 1000)); } @@ -773,11 +786,12 @@ static int increase_dsc_bpp(struct drm_atomic_state *state, int link_timeslots_used; int fair_pbn_alloc; int ret = 0; + uint16_t fec_overhead_multiplier_x1000 = get_fec_overhead_multiplier(dc_link); for (i = 0; i < count; i++) { if (vars[i + k].dsc_enabled) { initial_slack[i] = - kbps_to_peak_pbn(params[i].bw_range.max_kbps) - vars[i + k].pbn; + kbps_to_peak_pbn(params[i].bw_range.max_kbps, fec_overhead_multiplier_x1000) - vars[i + k].pbn; bpp_increased[i] = false; remaining_to_increase += 1; } else { @@ -873,6 +887,7 @@ static int try_disable_dsc(struct drm_atomic_state *state, int next_index; int remaining_to_try = 0; int ret; + uint16_t fec_overhead_multiplier_x1000 = get_fec_overhead_multiplier(dc_link); for (i = 0; i < count; i++) { if (vars[i + k].dsc_enabled @@ -902,7 +917,7 @@ static int try_disable_dsc(struct drm_atomic_state *state, if (next_index == -1) break; - vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.stream_kbps); + vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.stream_kbps, fec_overhead_multiplier_x1000); ret = drm_dp_atomic_find_time_slots(state, params[next_index].port->mgr, params[next_index].port, @@ -915,7 +930,7 @@ static int try_disable_dsc(struct drm_atomic_state *state, vars[next_index].dsc_enabled = false; vars[next_index].bpp_x16 = 0; } else { - vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.max_kbps); + vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.max_kbps, fec_overhead_multiplier_x1000); ret = drm_dp_atomic_find_time_slots(state, params[next_index].port->mgr, params[next_index].port, @@ -944,6 +959,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state, int count = 0; int i, k, ret; bool debugfs_overwrite = false; + uint16_t fec_overhead_multiplier_x1000 = get_fec_overhead_multiplier(dc_link); memset(params, 0, sizeof(params)); @@ -1005,7 +1021,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state, /* Try no compression */ for (i = 0; i < count; i++) { vars[i + k].aconnector = params[i].aconnector; - vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps); + vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps, fec_overhead_multiplier_x1000); vars[i + k].dsc_enabled = false; vars[i + k].bpp_x16 = 0; ret = drm_dp_atomic_find_time_slots(state, params[i].port->mgr, params[i].port, @@ -1024,7 +1040,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state, /* Try max compression */ for (i = 0; i < count; i++) { if (params[i].compression_possible && params[i].clock_force_enable != DSC_CLK_FORCE_DISABLE) { - vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.min_kbps); + vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.min_kbps, fec_overhead_multiplier_x1000); vars[i + k].dsc_enabled = true; vars[i + k].bpp_x16 = params[i].bw_range.min_target_bpp_x16; ret = drm_dp_atomic_find_time_slots(state, params[i].port->mgr, @@ -1032,7 +1048,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state, if (ret < 0) return ret; } else { - vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps); + vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps, fec_overhead_multiplier_x1000); vars[i + k].dsc_enabled = false; vars[i + k].bpp_x16 = 0; ret = drm_dp_atomic_find_time_slots(state, params[i].port->mgr, diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h index 0b5750202e73..1e4ede1e57ab 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h @@ -46,6 +46,9 @@ #define SYNAPTICS_CASCADED_HUB_ID 0x5A #define IS_SYNAPTICS_CASCADED_PANAMERA(devName, data) ((IS_SYNAPTICS_PANAMERA(devName) && ((int)data[2] == SYNAPTICS_CASCADED_HUB_ID)) ? 1 : 0) +#define PBN_FEC_OVERHEAD_MULTIPLIER_8B_10B 1031 +#define PBN_FEC_OVERHEAD_MULTIPLIER_128B_132B 1000 + struct amdgpu_display_manager; struct amdgpu_dm_connector;
