From b96a1d8c5189452d80551f2c38ef50c533c19669 Mon Sep 17 00:00:00 2001 From: Ben Skeggs Date: Tue, 23 Nov 2021 18:17:52 +1000 Subject: drm/nouveau/disp/dp: generate supported link rates table at detect time Replaces the static list used during link training with a table built dynamically from the union of source and sink capabilities. Preparation for adding support for HBR3, LTTPR and eDP 1.4 link rates. Signed-off-by: Ben Skeggs Reviewed-by: Lyude Paul Signed-off-by: Karol Herbst Link: https://gitlab.freedesktop.org/drm/nouveau/-/merge_requests/17 --- drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c | 108 ++++++++++---------------- drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h | 6 ++ 2 files changed, 45 insertions(+), 69 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c index 3c0554a60ba9..8b49398a91c5 100644 --- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c +++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c @@ -350,63 +350,13 @@ nvkm_dp_train_init(struct nvkm_dp *dp) } } -static const struct dp_rates { - u32 rate; - u8 bw; - u8 nr; -} nvkm_dp_rates[] = { - { 2160000, 0x14, 4 }, - { 1080000, 0x0a, 4 }, - { 1080000, 0x14, 2 }, - { 648000, 0x06, 4 }, - { 540000, 0x0a, 2 }, - { 540000, 0x14, 1 }, - { 324000, 0x06, 2 }, - { 270000, 0x0a, 1 }, - { 162000, 0x06, 1 }, - {} -}; - static int nvkm_dp_train(struct nvkm_dp *dp, u32 dataKBps) { struct nvkm_ior *ior = dp->outp.ior; - const u8 sink_nr = dp->dpcd[DPCD_RC02] & DPCD_RC02_MAX_LANE_COUNT; - const u8 sink_bw = dp->dpcd[DPCD_RC01_MAX_LINK_RATE]; - const u8 outp_nr = dp->outp.info.dpconf.link_nr; - const u8 outp_bw = dp->outp.info.dpconf.link_bw; - const struct dp_rates *failsafe = NULL, *cfg; - int ret = -EINVAL; + int ret = -EINVAL, nr, rate; u8 pwr; - /* Find the lowest configuration of the OR that can support - * the required link rate. - * - * We will refuse to program the OR to lower rates, even if - * link training fails at higher rates (or even if the sink - * can't support the rate at all, though the DD is supposed - * to prevent such situations from happening). - * - * Attempting to do so can cause the entire display to hang, - * and it's better to have a failed modeset than that. - */ - for (cfg = nvkm_dp_rates; cfg->rate; cfg++) { - if (cfg->nr <= outp_nr && cfg->bw <= outp_bw) { - /* Try to respect sink limits too when selecting - * lowest link configuration. - */ - if (!failsafe || - (cfg->nr <= sink_nr && cfg->bw <= sink_bw)) - failsafe = cfg; - } - - if (failsafe && cfg[1].rate < dataKBps) - break; - } - - if (WARN_ON(!failsafe)) - return ret; - /* Ensure sink is not in a low-power state. */ if (!nvkm_rdaux(dp->aux, DPCD_SC00, &pwr, 1)) { if ((pwr & DPCD_SC00_SET_POWER) != DPCD_SC00_SET_POWER_D0) { @@ -416,25 +366,22 @@ nvkm_dp_train(struct nvkm_dp *dp, u32 dataKBps) } } + ior->dp.mst = dp->lt.mst; + ior->dp.ef = dp->dpcd[DPCD_RC02] & DPCD_RC02_ENHANCED_FRAME_CAP; + ior->dp.nr = 0; + /* Link training. */ - OUTP_DBG(&dp->outp, "training (min: %d x %d MB/s)", - failsafe->nr, failsafe->bw * 27); + OUTP_DBG(&dp->outp, "training"); nvkm_dp_train_init(dp); - for (cfg = nvkm_dp_rates; ret < 0 && cfg <= failsafe; cfg++) { - /* Skip configurations not supported by both OR and sink. */ - if ((cfg->nr > outp_nr || cfg->bw > outp_bw || - cfg->nr > sink_nr || cfg->bw > sink_bw)) { - if (cfg != failsafe) - continue; - OUTP_ERR(&dp->outp, "link rate unsupported by sink"); + for (nr = dp->links; ret < 0 && nr; nr >>= 1) { + for (rate = 0; ret < 0 && rate < dp->rates; rate++) { + if (dp->rate[rate].rate * nr >= dataKBps || WARN_ON(!ior->dp.nr)) { + /* Program selected link configuration. */ + ior->dp.bw = dp->rate[rate].rate / 27000; + ior->dp.nr = nr; + ret = nvkm_dp_train_links(dp); + } } - ior->dp.mst = dp->lt.mst; - ior->dp.ef = dp->dpcd[DPCD_RC02] & DPCD_RC02_ENHANCED_FRAME_CAP; - ior->dp.bw = cfg->bw; - ior->dp.nr = cfg->nr; - - /* Program selected link configuration. */ - ret = nvkm_dp_train_links(dp); } nvkm_dp_train_fini(dp); if (ret < 0) @@ -543,9 +490,32 @@ nvkm_dp_enable(struct nvkm_dp *dp, bool enable) dp->present = true; } - if (!nvkm_rdaux(aux, DPCD_RC00_DPCD_REV, dp->dpcd, - sizeof(dp->dpcd))) + if (!nvkm_rdaux(aux, DPCD_RC00_DPCD_REV, dp->dpcd, sizeof(dp->dpcd))) { + const u8 rates[] = { 0x14, 0x0a, 0x06, 0 }; + const u8 *rate; + int rate_max; + + dp->rates = 0; + dp->links = dp->dpcd[DPCD_RC02] & DPCD_RC02_MAX_LANE_COUNT; + dp->links = min(dp->links, dp->outp.info.dpconf.link_nr); + + rate_max = dp->dpcd[DPCD_RC01_MAX_LINK_RATE]; + rate_max = min(rate_max, dp->outp.info.dpconf.link_bw); + + if (1) { + for (rate = rates; *rate; rate++) { + if (*rate <= rate_max) { + if (WARN_ON(dp->rates == ARRAY_SIZE(dp->rate))) + break; + + dp->rate[dp->rates].rate = *rate * 27000; + dp->rates++; + } + } + } + return true; + } } if (dp->present) { diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h index 9ce91f79ca35..8a8d0da58277 100644 --- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h +++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h @@ -20,6 +20,12 @@ struct nvkm_dp { bool present; u8 dpcd[16]; + struct { + u32 rate; + } rate[3]; + int rates; + int links; + struct mutex mutex; struct { atomic_t done; -- cgit v1.2.3-59-g8ed1b