Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Ben Skeggs bskeggs@redhat.com --- drivers/gpu/drm/nouveau/nouveau_dp.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c index 8a0f7994e1aeb..ee778ddc95fae 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dp.c +++ b/drivers/gpu/drm/nouveau/nouveau_dp.c @@ -76,10 +76,10 @@ nouveau_dp_detect(struct nouveau_encoder *nv_encoder) nv_encoder->dp.link_nr = dpcd[2] & DP_MAX_LANE_COUNT_MASK;

NV_DEBUG(drm, "display: %dx%d dpcd 0x%02x\n", - nv_encoder->dp.link_nr, nv_encoder->dp.link_bw, dpcd[0]); + nv_encoder->dp.link_nr, nv_encoder->dp.link_bw, dpcd[0]); NV_DEBUG(drm, "encoder: %dx%d\n", - nv_encoder->dcb->dpconf.link_nr, - nv_encoder->dcb->dpconf.link_bw); + nv_encoder->dcb->dpconf.link_nr, + nv_encoder->dcb->dpconf.link_bw);

if (nv_encoder->dcb->dpconf.link_nr < nv_encoder->dp.link_nr) nv_encoder->dp.link_nr = nv_encoder->dcb->dpconf.link_nr; @@ -87,7 +87,7 @@ nouveau_dp_detect(struct nouveau_encoder *nv_encoder) nv_encoder->dp.link_bw = nv_encoder->dcb->dpconf.link_bw;

NV_DEBUG(drm, "maximum: %dx%d\n", - nv_encoder->dp.link_nr, nv_encoder->dp.link_bw); + nv_encoder->dp.link_nr, nv_encoder->dp.link_bw);

nouveau_dp_probe_oui(dev, aux, dpcd);

Since this actually logs accesses, we should probably always be using this imho…

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Ben Skeggs bskeggs@redhat.com --- drivers/gpu/drm/nouveau/nouveau_dp.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c index c4e9c21d4dd2b..8db9216d52c69 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dp.c +++ b/drivers/gpu/drm/nouveau/nouveau_dp.c @@ -42,16 +42,12 @@ nouveau_dp_detect(struct nouveau_connector *nv_connector, { struct drm_device *dev = nv_encoder->base.base.dev; struct nouveau_drm *drm = nouveau_drm(dev); - struct nvkm_i2c_aux *aux; - u8 dpcd[8]; + struct drm_dp_aux *aux = &nv_connector->aux; + u8 dpcd[DP_RECEIVER_CAP_SIZE]; int ret;

- aux = nv_encoder->aux; - if (!aux) - return -ENODEV; - - ret = nvkm_rdaux(aux, DP_DPCD_REV, dpcd, sizeof(dpcd)); - if (ret) + ret = drm_dp_dpcd_read(aux, DP_DPCD_REV, dpcd, DP_RECEIVER_CAP_SIZE); + if (ret != sizeof(dpcd)) return ret;

nv_encoder->dp.link_bw = 27000 * dpcd[1];

Since fa3cdf8d0b09 ("drm/nouveau: Reset MST branching unit before enabling") we've been clearing DP_MST_CTRL before we start enabling MST. Since then clearing DP_MST_CTRL in nv50_mstm_new() has been unnecessary and redundant, so let's remove it.

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Ben Skeggs bskeggs@redhat.com --- drivers/gpu/drm/nouveau/dispnv50/disp.c | 11 ----------- 1 file changed, 11 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c index e7874877da858..c4d138f0ca054 100644 --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c @@ -1535,17 +1535,6 @@ nv50_mstm_new(struct nouveau_encoder *outp, struct drm_dp_aux *aux, int aux_max, struct drm_device *dev = outp->base.base.dev; struct nv50_mstm *mstm; int ret; - u8 dpcd; - - /* This is a workaround for some monitors not functioning - * correctly in MST mode on initial module load. I think - * some bad interaction with the VBIOS may be responsible. - * - * A good ol' off and on again seems to work here ;) - */ - ret = drm_dp_dpcd_readb(aux, DP_DPCD_REV, &dpcd); - if (ret >= 0 && dpcd >= 0x12) - drm_dp_dpcd_writeb(aux, DP_MSTM_CTRL, 0);

if (!(mstm = *pmstm = kzalloc(sizeof(*mstm), GFP_KERNEL))) return -ENOMEM;

First some backstory here: Currently, we keep track of whether or not we've enabled MST or not by trying to piggy-back off the MST helpers. This means that in order to check whether MST is enabled or not, we actually need to grab drm_dp_mst_topology_mgr.lock.

Back when I originally wrote this, I did this piggy-backing with the intention that I'd eventually be teaching our MST helpers how to recover when an MST device has stopped responding, which in turn would require the MST helpers having a way of disabling MST independently of the driver. Note that this was before I reworked locking in the MST helpers, so at the time we were sticking random things under &mgr->lock - which grabbing this lock was meant to protect against.

This never came to fruition because doing such a reset safely turned out to be a lot more painful and impossible then it sounds, and also just risks us working around issues with our MST handlers that should be properly fixed instead. Even if it did though, simply calling drm_dp_mst_topology_mgr_set_mst() from the MST helpers (with the exception of when we're tearing down our MST managers, that's always OK) wouldn't have been a bad idea, since drivers like nouveau and i915 need to do their own book keeping immediately after disabling MST. So-implementing that would likely require adding a hook for helper-triggered MST disables anyway.

So, fast forward to now - we want to start adding support for all of the miscellaneous bits of the DP protocol (for both SST and MST) we're missing before moving on to supporting more complicated features like supporting different BPP values on MST, DSC, etc. Since many of these features only exist on SST and make use of DP HPD IRQs, we want to be able to atomically check whether we're servicing an MST IRQ or SST IRQ in nouveau_connector_hotplug(). Currently we literally don't do this at all, and just handle any kind of possible DP IRQ we could get including ESIs - even if MST isn't actually enabled.

This would be very complicated and difficult to fix if we need to hold &mgr->lock while handling SST IRQs to ensure that the MST topology state doesn't change under us. What we really want here is to do our own tracking of whether MST is enabled or not, similar to drivers like i915, and define our own locking order to decomplicate things and avoid hitting locking issues in the future.

So, let's do this by refactoring our MST probing/enabling code to use our own MST bookkeeping, along with adding a lock for protecting DP state that needs to be checked outside of our connector probing functions. While we're at it, we also remove a bunch of unneeded steps we perform when probing/enabling MST:

* Enabling bits in MSTM_CTRL before calling drm_dp_mst_topology_mgr_set_mst(). I don't think these ever actually did anything, since the nvif methods for enabling MST don't actually do anything DPCD related and merely indicate to nvkm that we've turned on MST. * Checking the MSTM_CTRL bit is intact when checking the state of an enabled MST topology in nv50_mstm_detect(). I just added this to be safe originally, but now that we try reading the DPCD when probing DP connectors it shouldn't be needed as that will abort our hotplug probing if the device was removed well before we start checking for MST.. * All of the duplicate DPCD version checks.

This leaves us with much nicer looking code, a much more sensible locking scheme, and an easy way of checking whether MST is enabled or not for handling DP HPD IRQs.

v2: * Get rid of accidental newlines

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Ben Skeggs bskeggs@redhat.com --- drivers/gpu/drm/nouveau/dispnv04/disp.c | 6 +- drivers/gpu/drm/nouveau/dispnv50/disp.c | 196 +++++++++----------- drivers/gpu/drm/nouveau/nouveau_connector.c | 14 +- drivers/gpu/drm/nouveau/nouveau_display.c | 2 +- drivers/gpu/drm/nouveau/nouveau_display.h | 2 +- drivers/gpu/drm/nouveau/nouveau_dp.c | 132 +++++++++++-- drivers/gpu/drm/nouveau/nouveau_encoder.h | 33 +++- 7 files changed, 245 insertions(+), 140 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/dispnv04/disp.c b/drivers/gpu/drm/nouveau/dispnv04/disp.c index 3f046b917c85c..3ee836dc5058f 100644 --- a/drivers/gpu/drm/nouveau/dispnv04/disp.c +++ b/drivers/gpu/drm/nouveau/dispnv04/disp.c @@ -54,8 +54,9 @@ nv04_encoder_get_connector(struct nouveau_encoder *encoder) }

static void -nv04_display_fini(struct drm_device *dev, bool suspend) +nv04_display_fini(struct drm_device *dev, bool runtime, bool suspend) { + struct nouveau_drm *drm = nouveau_drm(dev); struct nv04_display *disp = nv04_display(dev); struct drm_crtc *crtc;

@@ -67,6 +68,9 @@ nv04_display_fini(struct drm_device *dev, bool suspend) if (nv_two_heads(dev)) NVWriteCRTC(dev, 1, NV_PCRTC_INTR_EN_0, 0);

+ if (!runtime) + cancel_work_sync(&drm->hpd_work); + if (!suspend) return;

diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c index 75005268941b9..0d6879c532bec 100644 --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c @@ -878,16 +878,6 @@ nv50_hdmi_enable(struct drm_encoder *encoder, struct drm_atomic_state *state, #define nv50_mstc(p) container_of((p), struct nv50_mstc, connector) #define nv50_msto(p) container_of((p), struct nv50_msto, encoder)

-struct nv50_mstm { - struct nouveau_encoder *outp; - - struct drm_dp_mst_topology_mgr mgr; - - bool modified; - bool disabled; - int links; -}; - struct nv50_mstc { struct nv50_mstm *mstm; struct drm_dp_mst_port *port; @@ -1416,41 +1406,51 @@ nv50_mstm = { .add_connector = nv50_mstm_add_connector, };

-void -nv50_mstm_service(struct nv50_mstm *mstm) +bool +nv50_mstm_service(struct nouveau_drm *drm, + struct nouveau_connector *nv_connector, + struct nv50_mstm *mstm) { - struct drm_dp_aux *aux = mstm ? mstm->mgr.aux : NULL; - bool handled = true; - int ret; + struct drm_dp_aux *aux = &nv_connector->aux; + bool handled = true, ret = true; + int rc; u8 esi[8] = {};

- if (!aux) - return; - while (handled) { - ret = drm_dp_dpcd_read(aux, DP_SINK_COUNT_ESI, esi, 8); - if (ret != 8) { - drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, false); - return; + rc = drm_dp_dpcd_read(aux, DP_SINK_COUNT_ESI, esi, 8); + if (rc != 8) { + ret = false; + break; }

drm_dp_mst_hpd_irq(&mstm->mgr, esi, &handled); if (!handled) break;

- drm_dp_dpcd_write(aux, DP_SINK_COUNT_ESI + 1, &esi[1], 3); + rc = drm_dp_dpcd_write(aux, DP_SINK_COUNT_ESI + 1, &esi[1], + 3); + if (rc != 3) { + ret = false; + break; + } } + + if (!ret) + NV_DEBUG(drm, "Failed to handle ESI on %s: %d\n", + nv_connector->base.name, rc); + + return ret; }

void nv50_mstm_remove(struct nv50_mstm *mstm) { - if (mstm) - drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, false); + mstm->is_mst = false; + drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, false); }

static int -nv50_mstm_enable(struct nv50_mstm *mstm, u8 dpcd, int state) +nv50_mstm_enable(struct nv50_mstm *mstm, int state) { struct nouveau_encoder *outp = mstm->outp; struct { @@ -1465,106 +1465,83 @@ nv50_mstm_enable(struct nv50_mstm *mstm, u8 dpcd, int state) }; struct nouveau_drm *drm = nouveau_drm(outp->base.base.dev); struct nvif_object *disp = &drm->display->disp.object; - int ret; - - if (dpcd >= 0x12) { - /* Even if we're enabling MST, start with disabling the - * branching unit to clear any sink-side MST topology state - * that wasn't set by us - */ - ret = drm_dp_dpcd_writeb(mstm->mgr.aux, DP_MSTM_CTRL, 0); - if (ret < 0) - return ret; - - if (state) { - /* Now, start initializing */ - ret = drm_dp_dpcd_writeb(mstm->mgr.aux, DP_MSTM_CTRL, - DP_MST_EN); - if (ret < 0) - return ret; - } - }

return nvif_mthd(disp, 0, &args, sizeof(args)); }

int -nv50_mstm_detect(struct nv50_mstm *mstm, u8 dpcd[8], int allow) +nv50_mstm_detect(struct nouveau_encoder *outp) { - struct drm_dp_aux *aux; + struct nv50_mstm *mstm = outp->dp.mstm; + struct drm_dp_aux *aux = mstm->mgr.aux; int ret; - bool old_state, new_state; - u8 mstm_ctrl;

- if (!mstm) + if (!mstm || !mstm->can_mst) return 0;

- mutex_lock(&mstm->mgr.lock); - - old_state = mstm->mgr.mst_state; - new_state = old_state; - aux = mstm->mgr.aux; - - if (old_state) { - /* Just check that the MST hub is still as we expect it */ - ret = drm_dp_dpcd_readb(aux, DP_MSTM_CTRL, &mstm_ctrl); - if (ret < 0 || !(mstm_ctrl & DP_MST_EN)) { - DRM_DEBUG_KMS("Hub gone, disabling MST topology\n"); - new_state = false; - } - } else if (dpcd[0] >= 0x12) { - ret = drm_dp_dpcd_readb(aux, DP_MSTM_CAP, &dpcd[1]); - if (ret < 0) - goto probe_error; - - if (!(dpcd[1] & DP_MST_CAP)) - dpcd[0] = 0x11; - else - new_state = allow; - } - - if (new_state == old_state) { - mutex_unlock(&mstm->mgr.lock); - return new_state; - } - - ret = nv50_mstm_enable(mstm, dpcd[0], new_state); - if (ret) - goto probe_error; - - mutex_unlock(&mstm->mgr.lock); + /* Clear any leftover MST state we didn't set ourselves by first + * disabling MST if it was already enabled + */ + ret = drm_dp_dpcd_writeb(aux, DP_MSTM_CTRL, 0); + if (ret < 0) + return ret;

- ret = drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, new_state); + /* And start enabling */ + ret = nv50_mstm_enable(mstm, true); if (ret) - return nv50_mstm_enable(mstm, dpcd[0], 0); + return ret;

- return new_state; + ret = drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, true); + if (ret) { + nv50_mstm_enable(mstm, false); + return ret; + }

-probe_error: - mutex_unlock(&mstm->mgr.lock); - return ret; + mstm->is_mst = true; + return 1; }

static void -nv50_mstm_fini(struct nv50_mstm *mstm) +nv50_mstm_fini(struct nouveau_encoder *outp) { - if (mstm && mstm->mgr.mst_state) + struct nv50_mstm *mstm = outp->dp.mstm; + + if (!mstm) + return; + + /* Don't change the MST state of this connector until we've finished + * resuming, since we can't safely grab hpd_irq_lock in our resume + * path to protect mstm->is_mst without potentially deadlocking + */ + mutex_lock(&outp->dp.hpd_irq_lock); + mstm->suspended = true; + mutex_unlock(&outp->dp.hpd_irq_lock); + + if (mstm->is_mst) drm_dp_mst_topology_mgr_suspend(&mstm->mgr); }

static void -nv50_mstm_init(struct nv50_mstm *mstm, bool runtime) +nv50_mstm_init(struct nouveau_encoder *outp, bool runtime) { - int ret; + struct nv50_mstm *mstm = outp->dp.mstm; + int ret = 0;

- if (!mstm || !mstm->mgr.mst_state) + if (!mstm) return;

- ret = drm_dp_mst_topology_mgr_resume(&mstm->mgr, !runtime); - if (ret == -1) { - drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, false); - drm_kms_helper_hotplug_event(mstm->mgr.dev); + if (mstm->is_mst) { + ret = drm_dp_mst_topology_mgr_resume(&mstm->mgr, !runtime); + if (ret == -1) + nv50_mstm_remove(mstm); } + + mutex_lock(&outp->dp.hpd_irq_lock); + mstm->suspended = false; + mutex_unlock(&outp->dp.hpd_irq_lock); + + if (ret == -1) + drm_kms_helper_hotplug_event(mstm->mgr.dev); }

static void @@ -1772,6 +1749,10 @@ nv50_sor_destroy(struct drm_encoder *encoder) struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder); nv50_mstm_del(&nv_encoder->dp.mstm); drm_encoder_cleanup(encoder); + + if (nv_encoder->dcb->type == DCB_OUTPUT_DP) + mutex_destroy(&nv_encoder->dp.hpd_irq_lock); + kfree(encoder); }

@@ -1831,6 +1812,8 @@ nv50_sor_create(struct drm_connector *connector, struct dcb_output *dcbe) struct nvkm_i2c_aux *aux = nvkm_i2c_aux_find(i2c, dcbe->i2c_index);

+ mutex_init(&nv_encoder->dp.hpd_irq_lock); + if (aux) { if (disp->disp->object.oclass < GF110_DISP) { /* HW has no support for address-only @@ -2529,9 +2512,9 @@ nv50_disp_func = { *****************************************************************************/

static void -nv50_display_fini(struct drm_device *dev, bool suspend) +nv50_display_fini(struct drm_device *dev, bool runtime, bool suspend) { - struct nouveau_encoder *nv_encoder; + struct nouveau_drm *drm = nouveau_drm(dev); struct drm_encoder *encoder; struct drm_plane *plane;

@@ -2543,11 +2526,12 @@ nv50_display_fini(struct drm_device *dev, bool suspend) }

list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) { - if (encoder->encoder_type != DRM_MODE_ENCODER_DPMST) { - nv_encoder = nouveau_encoder(encoder); - nv50_mstm_fini(nv_encoder->dp.mstm); - } + if (encoder->encoder_type != DRM_MODE_ENCODER_DPMST) + nv50_mstm_fini(nouveau_encoder(encoder)); } + + if (!runtime) + cancel_work_sync(&drm->hpd_work); }

static int @@ -2564,7 +2548,7 @@ nv50_display_init(struct drm_device *dev, bool resume, bool runtime) if (encoder->encoder_type != DRM_MODE_ENCODER_DPMST) { struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder); - nv50_mstm_init(nv_encoder->dp.mstm, runtime); + nv50_mstm_init(nv_encoder, runtime); } }

diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c index 1d5696c39792a..b90591114faaf 100644 --- a/drivers/gpu/drm/nouveau/nouveau_connector.c +++ b/drivers/gpu/drm/nouveau/nouveau_connector.c @@ -1143,19 +1143,15 @@ nouveau_connector_hotplug(struct nvif_notify *notify) struct nouveau_connector *nv_connector = container_of(notify, typeof(*nv_connector), hpd); struct drm_connector *connector = &nv_connector->base; - struct nouveau_drm *drm = nouveau_drm(connector->dev); + struct drm_device *dev = connector->dev; + struct nouveau_drm *drm = nouveau_drm(dev); const struct nvif_notify_conn_rep_v0 *rep = notify->data; const char *name = connector->name; - struct nouveau_encoder *nv_encoder; int ret; bool plugged = (rep->mask != NVIF_NOTIFY_CONN_V0_UNPLUG);

if (rep->mask & NVIF_NOTIFY_CONN_V0_IRQ) { - NV_DEBUG(drm, "service %s\n", name); - drm_dp_cec_irq(&nv_connector->aux); - if ((nv_encoder = find_encoder(connector, DCB_OUTPUT_DP))) - nv50_mstm_service(nv_encoder->dp.mstm); - + nouveau_dp_irq(drm, nv_connector); return NVIF_NOTIFY_KEEP; }

@@ -1181,10 +1177,6 @@ nouveau_connector_hotplug(struct nvif_notify *notify) if (!plugged) drm_dp_cec_unset_edid(&nv_connector->aux); NV_DEBUG(drm, "%splugged %s\n", plugged ? "" : "un", name); - if ((nv_encoder = find_encoder(connector, DCB_OUTPUT_DP))) { - if (!plugged) - nv50_mstm_remove(nv_encoder->dp.mstm); - }

drm_helper_hpd_irq_event(connector->dev);

diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c index 5f31b11ac2e7e..13016769a194b 100644 --- a/drivers/gpu/drm/nouveau/nouveau_display.c +++ b/drivers/gpu/drm/nouveau/nouveau_display.c @@ -569,7 +569,7 @@ nouveau_display_fini(struct drm_device *dev, bool suspend, bool runtime) cancel_work_sync(&drm->hpd_work);

drm_kms_helper_poll_disable(dev); - disp->fini(dev, suspend); + disp->fini(dev, runtime, suspend); }

static void diff --git a/drivers/gpu/drm/nouveau/nouveau_display.h b/drivers/gpu/drm/nouveau/nouveau_display.h index 6e0d900441d69..76ba93e01aff4 100644 --- a/drivers/gpu/drm/nouveau/nouveau_display.h +++ b/drivers/gpu/drm/nouveau/nouveau_display.h @@ -18,7 +18,7 @@ struct nouveau_display { void *priv; void (*dtor)(struct drm_device *); int (*init)(struct drm_device *, bool resume, bool runtime); - void (*fini)(struct drm_device *, bool suspend); + void (*fini)(struct drm_device *, bool suspend, bool runtime);

struct nvif_disp disp;

diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c index 4030806e3522b..032afc73e2a33 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dp.c +++ b/drivers/gpu/drm/nouveau/nouveau_dp.c @@ -36,19 +36,89 @@ MODULE_PARM_DESC(mst, "Enable DisplayPort multi-stream (default: enabled)"); static int nouveau_mst = 1; module_param_named(mst, nouveau_mst, int, 0400);

+static enum drm_connector_status +nouveau_dp_probe_dpcd(struct nouveau_connector *nv_connector, + struct nouveau_encoder *outp) +{ + struct drm_dp_aux *aux = &nv_connector->aux; + struct nv50_mstm *mstm = NULL; + int ret; + u8 *dpcd = outp->dp.dpcd; + u8 tmp; + + ret = drm_dp_dpcd_read(aux, DP_DPCD_REV, dpcd, DP_RECEIVER_CAP_SIZE); + if (ret == DP_RECEIVER_CAP_SIZE && dpcd[DP_DPCD_REV]) { + ret = drm_dp_read_desc(aux, &outp->dp.desc, + drm_dp_is_branch(dpcd)); + if (ret < 0) + return connector_status_disconnected; + } else { + return connector_status_disconnected; + } + + if (nouveau_mst) + mstm = outp->dp.mstm; + + if (mstm) { + if (dpcd[DP_DPCD_REV] >= DP_DPCD_REV_12) { + ret = drm_dp_dpcd_readb(aux, DP_MSTM_CAP, &tmp); + if (ret < 0) + return connector_status_disconnected; + + mstm->can_mst = !!(tmp & DP_MST_CAP); + } else { + mstm->can_mst = false; + } + } + + return connector_status_connected; +} + int nouveau_dp_detect(struct nouveau_connector *nv_connector, struct nouveau_encoder *nv_encoder) { struct drm_device *dev = nv_encoder->base.base.dev; struct nouveau_drm *drm = nouveau_drm(dev); - struct drm_dp_aux *aux = &nv_connector->aux; - u8 dpcd[DP_RECEIVER_CAP_SIZE]; - int ret; + struct drm_connector *connector = &nv_connector->base; + struct nv50_mstm *mstm = nv_encoder->dp.mstm; + enum drm_connector_status status; + u8 *dpcd = nv_encoder->dp.dpcd; + int ret = NOUVEAU_DP_NONE; + + /* If we've already read the DPCD on an eDP device, we don't need to + * reread it as it won't change + */ + if (connector->connector_type == DRM_MODE_CONNECTOR_eDP && + dpcd[DP_DPCD_REV] != 0) + return NOUVEAU_DP_SST;

- ret = drm_dp_dpcd_read(aux, DP_DPCD_REV, dpcd, DP_RECEIVER_CAP_SIZE); - if (ret != sizeof(dpcd)) - return ret; + mutex_lock(&nv_encoder->dp.hpd_irq_lock); + if (mstm) { + /* If we're not ready to handle MST state changes yet, just + * report the last status of the connector. We'll reprobe it + * once we've resumed. + */ + if (mstm->suspended) { + if (mstm->is_mst) + ret = NOUVEAU_DP_MST; + else if (connector->status == + connector_status_connected) + ret = NOUVEAU_DP_SST; + + goto out; + } + } + + status = nouveau_dp_probe_dpcd(nv_connector, nv_encoder); + if (status == connector_status_disconnected) + goto out; + + /* If we're in MST mode, we're done here */ + if (mstm && mstm->can_mst && mstm->is_mst) { + ret = NOUVEAU_DP_MST; + goto out; + }

nv_encoder->dp.link_bw = 27000 * dpcd[DP_MAX_LINK_RATE]; nv_encoder->dp.link_nr = @@ -69,22 +139,50 @@ nouveau_dp_detect(struct nouveau_connector *nv_connector, NV_DEBUG(drm, "maximum: %dx%d\n", nv_encoder->dp.link_nr, nv_encoder->dp.link_bw);

- ret = drm_dp_read_desc(&nv_connector->aux, &nv_encoder->dp.desc, - drm_dp_is_branch(dpcd)); - if (ret) { - NV_ERROR(drm, "Failed to read DP descriptor on %s: %d\n", - nv_connector->base.name, ret); - return ret; + if (mstm && mstm->can_mst) { + ret = nv50_mstm_detect(nv_encoder); + if (ret == 1) { + ret = NOUVEAU_DP_MST; + goto out; + } else if (ret != 0) { + goto out; + } } + ret = NOUVEAU_DP_SST;

- ret = nv50_mstm_detect(nv_encoder->dp.mstm, dpcd, nouveau_mst); - if (ret == 1) - return NOUVEAU_DP_MST; - if (ret == 0) - return NOUVEAU_DP_SST; +out: + if (mstm && !mstm->suspended && ret != NOUVEAU_DP_MST) + nv50_mstm_remove(mstm); + + mutex_unlock(&nv_encoder->dp.hpd_irq_lock); return ret; }

+void nouveau_dp_irq(struct nouveau_drm *drm, + struct nouveau_connector *nv_connector) +{ + struct drm_connector *connector = &nv_connector->base; + struct nouveau_encoder *outp = find_encoder(connector, DCB_OUTPUT_DP); + struct nv50_mstm *mstm; + + if (!outp) + return; + + mstm = outp->dp.mstm; + NV_DEBUG(drm, "service %s\n", connector->name); + + mutex_lock(&outp->dp.hpd_irq_lock); + + if (mstm && mstm->is_mst) { + if (!nv50_mstm_service(drm, nv_connector, mstm)) + schedule_work(&drm->hpd_work); + } else { + drm_dp_cec_irq(&nv_connector->aux); + } + + mutex_unlock(&outp->dp.hpd_irq_lock); +} + /* TODO: * - Use the minimum possible BPC here, once we add support for the max bpc * property. diff --git a/drivers/gpu/drm/nouveau/nouveau_encoder.h b/drivers/gpu/drm/nouveau/nouveau_encoder.h index b0e1dad2367d6..eef4643f5f982 100644 --- a/drivers/gpu/drm/nouveau/nouveau_encoder.h +++ b/drivers/gpu/drm/nouveau/nouveau_encoder.h @@ -65,6 +65,13 @@ struct nouveau_encoder { struct nv50_mstm *mstm; int link_nr; int link_bw; + + /* Protects DP state that needs to be accessed outside + * connector reprobing contexts + */ + struct mutex hpd_irq_lock; + + u8 dpcd[DP_RECEIVER_CAP_SIZE]; struct drm_dp_desc desc; } dp; }; @@ -79,6 +86,21 @@ struct nouveau_encoder { struct nv50_head_atom *, u8 proto, u8 depth); };

+struct nv50_mstm { + struct nouveau_encoder *outp; + + struct drm_dp_mst_topology_mgr mgr; + + /* Protected under nouveau_encoder->dp.hpd_irq_lock */ + bool can_mst; + bool is_mst; + bool suspended; + + bool modified; + bool disabled; + int links; +}; + struct nouveau_encoder * find_encoder(struct drm_connector *connector, int type);

@@ -102,11 +124,14 @@ get_slave_funcs(struct drm_encoder *enc)

/* nouveau_dp.c */ enum nouveau_dp_status { + NOUVEAU_DP_NONE, NOUVEAU_DP_SST, NOUVEAU_DP_MST, };

int nouveau_dp_detect(struct nouveau_connector *, struct nouveau_encoder *); +void nouveau_dp_irq(struct nouveau_drm *drm, + struct nouveau_connector *nv_connector); enum drm_mode_status nv50_dp_mode_valid(struct drm_connector *, struct nouveau_encoder *, const struct drm_display_mode *, @@ -119,7 +144,9 @@ struct nouveau_connector * nv50_outp_get_old_connector(struct nouveau_encoder *outp, struct drm_atomic_state *state);

-int nv50_mstm_detect(struct nv50_mstm *, u8 dpcd[8], int allow); -void nv50_mstm_remove(struct nv50_mstm *); -void nv50_mstm_service(struct nv50_mstm *); +int nv50_mstm_detect(struct nouveau_encoder *encoder); +void nv50_mstm_remove(struct nv50_mstm *mstm); +bool nv50_mstm_service(struct nouveau_drm *drm, + struct nouveau_connector *nv_connector, + struct nv50_mstm *mstm); #endif /* __NOUVEAU_ENCODER_H__ */

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Ben Skeggs bskeggs@redhat.com --- drivers/gpu/drm/nouveau/nouveau_dp.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c index 032afc73e2a33..201c0b4335563 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dp.c +++ b/drivers/gpu/drm/nouveau/nouveau_dp.c @@ -44,7 +44,6 @@ nouveau_dp_probe_dpcd(struct nouveau_connector *nv_connector, struct nv50_mstm *mstm = NULL; int ret; u8 *dpcd = outp->dp.dpcd; - u8 tmp;

ret = drm_dp_dpcd_read(aux, DP_DPCD_REV, dpcd, DP_RECEIVER_CAP_SIZE); if (ret == DP_RECEIVER_CAP_SIZE && dpcd[DP_DPCD_REV]) { @@ -56,19 +55,10 @@ nouveau_dp_probe_dpcd(struct nouveau_connector *nv_connector, return connector_status_disconnected; }

- if (nouveau_mst) + if (nouveau_mst) { mstm = outp->dp.mstm; - - if (mstm) { - if (dpcd[DP_DPCD_REV] >= DP_DPCD_REV_12) { - ret = drm_dp_dpcd_readb(aux, DP_MSTM_CAP, &tmp); - if (ret < 0) - return connector_status_disconnected; - - mstm->can_mst = !!(tmp & DP_MST_CAP); - } else { - mstm->can_mst = false; - } + if (mstm) + mstm->can_mst = drm_dp_has_mst(aux, dpcd); }

return connector_status_connected;

Currently we perform both short IRQ handling for DP, and connector reprobing in the HPD IRQ handler. However since we need to grab connection_mutex in order to reprobe a connector, in theory we could accidentally block ourselves from handling any short IRQs until after a modeset completes if a connector hotplug happens to occur in parallel with a modeset.

I haven't seen this actually happen yet, but since we're cleaning up nouveau's hotplug handling code anyway and we already have a hpd worker, we can simply fix this by only relying on the HPD worker to actually reprobe connectors when we receive a HPD IRQ. We also add a mask to nouveau_drm to keep track of which connectors are waiting to be reprobed in response to an HPD IRQ.

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Ben Skeggs bskeggs@redhat.com --- drivers/gpu/drm/nouveau/nouveau_connector.c | 42 +++++-------- drivers/gpu/drm/nouveau/nouveau_connector.h | 1 + drivers/gpu/drm/nouveau/nouveau_display.c | 70 ++++++++++++++++++--- drivers/gpu/drm/nouveau/nouveau_display.h | 1 + drivers/gpu/drm/nouveau/nouveau_dp.c | 2 +- drivers/gpu/drm/nouveau/nouveau_drm.c | 4 +- drivers/gpu/drm/nouveau/nouveau_drv.h | 2 + 7 files changed, 86 insertions(+), 36 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c index 4a29f691c08e4..637e91594fbe8 100644 --- a/drivers/gpu/drm/nouveau/nouveau_connector.c +++ b/drivers/gpu/drm/nouveau/nouveau_connector.c @@ -1138,6 +1138,20 @@ nouveau_connector_funcs_lvds = { .early_unregister = nouveau_connector_early_unregister, };

+void +nouveau_connector_hpd(struct drm_connector *connector) +{ + struct nouveau_drm *drm = nouveau_drm(connector->dev); + u32 mask = drm_connector_mask(connector); + + mutex_lock(&drm->hpd_lock); + if (!(drm->hpd_pending & mask)) { + drm->hpd_pending |= mask; + schedule_work(&drm->hpd_work); + } + mutex_unlock(&drm->hpd_lock); +} + static int nouveau_connector_hotplug(struct nvif_notify *notify) { @@ -1147,8 +1161,6 @@ nouveau_connector_hotplug(struct nvif_notify *notify) struct drm_device *dev = connector->dev; struct nouveau_drm *drm = nouveau_drm(dev); const struct nvif_notify_conn_rep_v0 *rep = notify->data; - const char *name = connector->name; - int ret; bool plugged = (rep->mask != NVIF_NOTIFY_CONN_V0_UNPLUG);

if (rep->mask & NVIF_NOTIFY_CONN_V0_IRQ) { @@ -1156,31 +1168,9 @@ nouveau_connector_hotplug(struct nvif_notify *notify) return NVIF_NOTIFY_KEEP; }

- ret = pm_runtime_get(drm->dev->dev); - if (ret == 0) { - /* We can't block here if there's a pending PM request - * running, as we'll deadlock nouveau_display_fini() when it - * calls nvif_put() on our nvif_notify struct. So, simply - * defer the hotplug event until the device finishes resuming - */ - NV_DEBUG(drm, "Deferring HPD on %s until runtime resume\n", - name); - schedule_work(&drm->hpd_work); - - pm_runtime_put_noidle(drm->dev->dev); - return NVIF_NOTIFY_KEEP; - } else if (ret != 1 && ret != -EACCES) { - NV_WARN(drm, "HPD on %s dropped due to RPM failure: %d\n", - name, ret); - return NVIF_NOTIFY_DROP; - } - - NV_DEBUG(drm, "%splugged %s\n", plugged ? "" : "un", name); - - drm_helper_hpd_irq_event(connector->dev); + NV_DEBUG(drm, "%splugged %s\n", plugged ? "" : "un", connector->name); + nouveau_connector_hpd(connector);

- pm_runtime_mark_last_busy(drm->dev->dev); - pm_runtime_put_autosuspend(drm->dev->dev); return NVIF_NOTIFY_KEEP; }

diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.h b/drivers/gpu/drm/nouveau/nouveau_connector.h index d6de5cb8e2238..d0b859c4a80ea 100644 --- a/drivers/gpu/drm/nouveau/nouveau_connector.h +++ b/drivers/gpu/drm/nouveau/nouveau_connector.h @@ -187,6 +187,7 @@ nouveau_crtc_connector_get(struct nouveau_crtc *nv_crtc)

struct drm_connector * nouveau_connector_create(struct drm_device *, const struct dcb_output *); +void nouveau_connector_hpd(struct drm_connector *connector);

extern int nouveau_tv_disable; extern int nouveau_ignorelid; diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c index 13016769a194b..bceb48a2dfca6 100644 --- a/drivers/gpu/drm/nouveau/nouveau_display.c +++ b/drivers/gpu/drm/nouveau/nouveau_display.c @@ -457,16 +457,70 @@ static struct nouveau_drm_prop_enum_list dither_depth[] = { } \ } while(0)

+void +nouveau_display_hpd_resume(struct drm_device *dev) +{ + struct nouveau_drm *drm = nouveau_drm(dev); + + mutex_lock(&drm->hpd_lock); + drm->hpd_pending = ~0; + mutex_unlock(&drm->hpd_lock); + + schedule_work(&drm->hpd_work); +} + static void nouveau_display_hpd_work(struct work_struct *work) { struct nouveau_drm *drm = container_of(work, typeof(*drm), hpd_work); + struct drm_device *dev = drm->dev; + struct drm_connector *connector; + struct drm_connector_list_iter conn_iter; + u32 pending; + bool changed = false; + + pm_runtime_get_sync(dev->dev);

- pm_runtime_get_sync(drm->dev->dev); + mutex_lock(&drm->hpd_lock); + pending = drm->hpd_pending; + drm->hpd_pending = 0; + mutex_unlock(&drm->hpd_lock);

- drm_helper_hpd_irq_event(drm->dev); + /* Nothing to do, exit early without updating the last busy counter */ + if (!pending) + goto noop; + + mutex_lock(&dev->mode_config.mutex); + drm_connector_list_iter_begin(dev, &conn_iter); + + nouveau_for_each_non_mst_connector_iter(connector, &conn_iter) { + enum drm_connector_status old_status = connector->status; + u64 old_epoch_counter = connector->epoch_counter; + + if (!(pending & drm_connector_mask(connector))) + continue; + + connector->status = drm_helper_probe_detect(connector, NULL, + false); + if (old_epoch_counter == connector->epoch_counter) + continue; + + changed = true; + drm_dbg_kms(dev, "[CONNECTOR:%d:%s] status updated from %s to %s (epoch counter %llu->%llu)\n", + connector->base.id, connector->name, + drm_get_connector_status_name(old_status), + drm_get_connector_status_name(connector->status), + old_epoch_counter, connector->epoch_counter); + } + + drm_connector_list_iter_end(&conn_iter); + mutex_unlock(&dev->mode_config.mutex); + + if (changed) + drm_kms_helper_hotplug_event(dev);

pm_runtime_mark_last_busy(drm->dev->dev); +noop: pm_runtime_put_sync(drm->dev->dev); }

@@ -490,12 +544,11 @@ nouveau_display_acpi_ntfy(struct notifier_block *nb, unsigned long val, */ pm_runtime_put_autosuspend(drm->dev->dev); } else if (ret == 0) { - /* This may be the only indication we receive - * of a connector hotplug on a runtime - * suspended GPU, schedule hpd_work to check. + /* We've started resuming the GPU already, so + * it will handle scheduling a full reprobe + * itself */ NV_DEBUG(drm, "ACPI requested connector reprobe\n"); - schedule_work(&drm->hpd_work); pm_runtime_put_noidle(drm->dev->dev); } else { NV_WARN(drm, "Dropped ACPI reprobe event due to RPM error: %d\n", @@ -686,6 +739,7 @@ nouveau_display_create(struct drm_device *dev) }

INIT_WORK(&drm->hpd_work, nouveau_display_hpd_work); + mutex_init(&drm->hpd_lock); #ifdef CONFIG_ACPI drm->acpi_nb.notifier_call = nouveau_display_acpi_ntfy; register_acpi_notifier(&drm->acpi_nb); @@ -705,9 +759,10 @@ void nouveau_display_destroy(struct drm_device *dev) { struct nouveau_display *disp = nouveau_display(dev); + struct nouveau_drm *drm = nouveau_drm(dev);

#ifdef CONFIG_ACPI - unregister_acpi_notifier(&nouveau_drm(dev)->acpi_nb); + unregister_acpi_notifier(&drm->acpi_nb); #endif

drm_kms_helper_poll_fini(dev); @@ -719,6 +774,7 @@ nouveau_display_destroy(struct drm_device *dev) nvif_disp_dtor(&disp->disp);

nouveau_drm(dev)->display = NULL; + mutex_destroy(&drm->hpd_lock); kfree(disp); }

diff --git a/drivers/gpu/drm/nouveau/nouveau_display.h b/drivers/gpu/drm/nouveau/nouveau_display.h index 76ba93e01aff4..616c434270594 100644 --- a/drivers/gpu/drm/nouveau/nouveau_display.h +++ b/drivers/gpu/drm/nouveau/nouveau_display.h @@ -45,6 +45,7 @@ nouveau_display(struct drm_device *dev) int nouveau_display_create(struct drm_device *dev); void nouveau_display_destroy(struct drm_device *dev); int nouveau_display_init(struct drm_device *dev, bool resume, bool runtime); +void nouveau_display_hpd_resume(struct drm_device *dev); void nouveau_display_fini(struct drm_device *dev, bool suspend, bool runtime); int nouveau_display_suspend(struct drm_device *dev, bool runtime); void nouveau_display_resume(struct drm_device *dev, bool runtime); diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c index 201c0b4335563..71d095409c90d 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dp.c +++ b/drivers/gpu/drm/nouveau/nouveau_dp.c @@ -165,7 +165,7 @@ void nouveau_dp_irq(struct nouveau_drm *drm,

if (mstm && mstm->is_mst) { if (!nv50_mstm_service(drm, nv_connector, mstm)) - schedule_work(&drm->hpd_work); + nouveau_connector_hpd(connector); } else { drm_dp_cec_irq(&nv_connector->aux); } diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c index 22d246acc5e52..42fc5c813a9bb 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drm.c +++ b/drivers/gpu/drm/nouveau/nouveau_drm.c @@ -953,7 +953,7 @@ nouveau_pmops_resume(struct device *dev) ret = nouveau_do_resume(drm_dev, false);

/* Monitors may have been connected / disconnected during suspend */ - schedule_work(&nouveau_drm(drm_dev)->hpd_work); + nouveau_display_hpd_resume(drm_dev);

return ret; } @@ -1036,7 +1036,7 @@ nouveau_pmops_runtime_resume(struct device *dev) drm_dev->switch_power_state = DRM_SWITCH_POWER_ON;

/* Monitors may have been connected / disconnected during suspend */ - schedule_work(&nouveau_drm(drm_dev)->hpd_work); + nouveau_display_hpd_resume(drm_dev);

return ret; } diff --git a/drivers/gpu/drm/nouveau/nouveau_drv.h b/drivers/gpu/drm/nouveau/nouveau_drv.h index f63ac72aa556f..73ebf5fba2fcd 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drv.h +++ b/drivers/gpu/drm/nouveau/nouveau_drv.h @@ -198,6 +198,8 @@ struct nouveau_drm { struct nvbios vbios; struct nouveau_display *display; struct work_struct hpd_work; + struct mutex hpd_lock; + u32 hpd_pending; struct work_struct fbcon_work; int fbcon_new_state; #ifdef CONFIG_ACPI

Since other drivers are also going to need to be aware of the sink count in order to do proper dongle detection, we might as well steal i915's DP_SINK_COUNT helpers and move them into DRM helpers so that other dirvers can use them as well.

Note that this also starts using intel_dp_has_sink_count() in intel_dp_detect_dpcd(), which is a functional change.

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Sean Paul sean@poorly.run --- drivers/gpu/drm/drm_dp_helper.c | 22 ++++++++++++++++++++++ drivers/gpu/drm/i915/display/intel_dp.c | 21 ++++++++++++--------- include/drm/drm_dp_helper.h | 8 +++++++- 3 files changed, 41 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 4f845995f1f66..863e0babc1903 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -714,6 +714,28 @@ void drm_dp_set_subconnector_property(struct drm_connector *connector, } EXPORT_SYMBOL(drm_dp_set_subconnector_property);

+/** + * drm_dp_has_sink_count() - Check whether a given connector has a valid sink + * count + * @connector: The DRM connector to check + * @dpcd: A cached copy of the connector's DPCD RX capabilities + * @desc: A cached copy of the connector's DP descriptor + * + * Returns: %True if the (e)DP connector has a valid sink count that should + * be probed, %false otherwise. + */ +bool drm_dp_has_sink_count(struct drm_connector *connector, + const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const struct drm_dp_desc *desc) +{ + /* Some eDP panels don't set a valid value for the sink count */ + return connector->connector_type != DRM_MODE_CONNECTOR_eDP && + dpcd[DP_DPCD_REV] >= DP_DPCD_REV_11 && + dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT && + !drm_dp_has_quirk(desc, 0, DP_DPCD_QUIRK_NO_SINK_COUNT); +} +EXPORT_SYMBOL(drm_dp_has_sink_count); + /* * I2C-over-AUX implementation */ diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 984e49194ca31..35a4779a442e2 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -4634,6 +4634,16 @@ intel_edp_init_dpcd(struct intel_dp *intel_dp) return true; }

+static bool +intel_dp_has_sink_count(struct intel_dp *intel_dp) +{ + if (!intel_dp->attached_connector) + return false; + + return drm_dp_has_sink_count(&intel_dp->attached_connector->base, + intel_dp->dpcd, + &intel_dp->desc); +}

static bool intel_dp_get_dpcd(struct intel_dp *intel_dp) @@ -4653,13 +4663,7 @@ intel_dp_get_dpcd(struct intel_dp *intel_dp) intel_dp_set_common_rates(intel_dp); }

- /* - * Some eDP panels do not set a valid value for sink count, that is why - * it don't care about read it here and in intel_edp_init_dpcd(). - */ - if (!intel_dp_is_edp(intel_dp) && - !drm_dp_has_quirk(&intel_dp->desc, 0, - DP_DPCD_QUIRK_NO_SINK_COUNT)) { + if (intel_dp_has_sink_count(intel_dp)) { u8 count; ssize_t r;

@@ -5939,9 +5943,8 @@ intel_dp_detect_dpcd(struct intel_dp *intel_dp) return connector_status_connected;

/* If we're HPD-aware, SINK_COUNT changes dynamically */ - if (intel_dp->dpcd[DP_DPCD_REV] >= 0x11 && + if (intel_dp_has_sink_count(intel_dp) && intel_dp->downstream_ports[0] & DP_DS_PORT_HPD) { - return intel_dp->sink_count ? connector_status_connected : connector_status_disconnected; } diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 1349f16564ace..a1413a531eaf4 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -1631,6 +1631,11 @@ void drm_dp_set_subconnector_property(struct drm_connector *connector, const u8 *dpcd, const u8 port_cap[4]);

+struct drm_dp_desc; +bool drm_dp_has_sink_count(struct drm_connector *connector, + const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const struct drm_dp_desc *desc); + void drm_dp_remote_aux_init(struct drm_dp_aux *aux); void drm_dp_aux_init(struct drm_dp_aux *aux); int drm_dp_aux_register(struct drm_dp_aux *aux); @@ -1689,7 +1694,8 @@ enum drm_dp_quirk { * @DP_DPCD_QUIRK_NO_SINK_COUNT: * * The device does not set SINK_COUNT to a non-zero value. - * The driver should ignore SINK_COUNT during detection. + * The driver should ignore SINK_COUNT during detection. Note that + * drm_dp_has_sink_count() automatically checks for this quirk. */ DP_DPCD_QUIRK_NO_SINK_COUNT, /**

This is another bit that we never implemented for nouveau: dongle detection. When a "dongle", e.g. an active display adaptor, is hooked up to the system and causes an HPD to be fired, we don't actually know whether or not there's anything plugged into the dongle without checking the sink count. As a result, plugging in a dongle without anything plugged into it currently results in a bogus EDID retrieval error in the kernel log.

Additionally, most dongles won't send another long HPD signal if the user suddenly plugs something in, they'll only send a short HPD IRQ with the expectation that the source will check the sink count and reprobe the connector if it's changed - something we don't actually do. As a result, nothing will happen if the user plugs the dongle in before plugging something into the dongle.

So, let's fix this by checking the sink count in both nouveau_dp_probe_dpcd() and nouveau_dp_irq(), and reprobing the connector if things change.

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Ben Skeggs bskeggs@redhat.com --- drivers/gpu/drm/nouveau/nouveau_dp.c | 54 ++++++++++++++++++++--- drivers/gpu/drm/nouveau/nouveau_encoder.h | 2 + 2 files changed, 51 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c index c200f197083f9..89afc97ee2591 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dp.c +++ b/drivers/gpu/drm/nouveau/nouveau_dp.c @@ -36,12 +36,22 @@ MODULE_PARM_DESC(mst, "Enable DisplayPort multi-stream (default: enabled)"); static int nouveau_mst = 1; module_param_named(mst, nouveau_mst, int, 0400);

+static bool +nouveau_dp_has_sink_count(struct drm_connector *connector, + struct nouveau_encoder *outp) +{ + return drm_dp_has_sink_count(connector, outp->dp.dpcd, + &outp->dp.desc); +} + static enum drm_connector_status nouveau_dp_probe_dpcd(struct nouveau_connector *nv_connector, struct nouveau_encoder *outp) { + struct drm_connector *connector = &nv_connector->base; struct drm_dp_aux *aux = &nv_connector->aux; struct nv50_mstm *mstm = NULL; + enum drm_connector_status status = connector_status_disconnected; int ret; u8 *dpcd = outp->dp.dpcd;

@@ -50,9 +60,9 @@ nouveau_dp_probe_dpcd(struct nouveau_connector *nv_connector, ret = drm_dp_read_desc(aux, &outp->dp.desc, drm_dp_is_branch(dpcd)); if (ret < 0) - return connector_status_disconnected; + goto out; } else { - return connector_status_disconnected; + goto out; }

if (nouveau_mst) { @@ -61,12 +71,33 @@ nouveau_dp_probe_dpcd(struct nouveau_connector *nv_connector, mstm->can_mst = drm_dp_has_mst(aux, dpcd); }

+ if (nouveau_dp_has_sink_count(connector, outp)) { + ret = drm_dp_get_sink_count(aux); + if (ret < 0) + goto out; + + outp->dp.sink_count = ret; + + /* + * Dongle connected, but no display. Don't bother reading + * downstream port info + */ + if (!outp->dp.sink_count) + return connector_status_disconnected; + } + ret = drm_dp_downstream_read_info(aux, dpcd, outp->dp.downstream_ports); if (ret < 0) - return connector_status_disconnected; + goto out;

- return connector_status_connected; + status = connector_status_connected; +out: + if (status != connector_status_connected) { + /* Clear any cached info */ + outp->dp.sink_count = 0; + } + return status; }

int @@ -159,6 +190,8 @@ void nouveau_dp_irq(struct nouveau_drm *drm, struct drm_connector *connector = &nv_connector->base; struct nouveau_encoder *outp = find_encoder(connector, DCB_OUTPUT_DP); struct nv50_mstm *mstm; + int ret; + bool send_hpd = false;

if (!outp) return; @@ -170,12 +203,23 @@ void nouveau_dp_irq(struct nouveau_drm *drm,

if (mstm && mstm->is_mst) { if (!nv50_mstm_service(drm, nv_connector, mstm)) - nouveau_connector_hpd(connector); + send_hpd = true; } else { drm_dp_cec_irq(&nv_connector->aux); + + if (nouveau_dp_has_sink_count(connector, outp)) { + ret = drm_dp_get_sink_count(&nv_connector->aux); + if (ret != outp->dp.sink_count) + send_hpd = true; + if (ret >= 0) + outp->dp.sink_count = ret; + } }

mutex_unlock(&outp->dp.hpd_irq_lock); + + if (send_hpd) + nouveau_connector_hpd(connector); }

/* TODO: diff --git a/drivers/gpu/drm/nouveau/nouveau_encoder.h b/drivers/gpu/drm/nouveau/nouveau_encoder.h index c1924a4529a7b..21937f1c7dd90 100644 --- a/drivers/gpu/drm/nouveau/nouveau_encoder.h +++ b/drivers/gpu/drm/nouveau/nouveau_encoder.h @@ -74,6 +74,8 @@ struct nouveau_encoder { u8 dpcd[DP_RECEIVER_CAP_SIZE]; u8 downstream_ports[DP_MAX_DOWNSTREAM_PORTS]; struct drm_dp_desc desc; + + u8 sink_count; } dp; };

Since DP 1.3, it's been possible for DP receivers to specify an additional set of DPCD capabilities, which can take precedence over the capabilities reported at DP_DPCD_REV.

Basically any device supporting DP is going to need to read these in an identical manner, in particular nouveau, so let's go ahead and just move this code out of i915 into a shared DRM DP helper that we can use in other drivers.

v2: * Remove redundant dpcd[DP_DPCD_REV] == 0 check * Fix drm_dp_dpcd_read() ret checks

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Sean Paul sean@poorly.run --- drivers/gpu/drm/drm_dp_helper.c | 77 +++++++++++++++++++++ drivers/gpu/drm/i915/display/intel_dp.c | 60 +--------------- drivers/gpu/drm/i915/display/intel_dp.h | 1 - drivers/gpu/drm/i915/display/intel_lspcon.c | 2 +- include/drm/drm_dp_helper.h | 3 + 5 files changed, 83 insertions(+), 60 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 67ad05eb05b7e..9c99d21b42c15 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -433,6 +433,83 @@ static u8 drm_dp_downstream_port_count(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) return port_count; }

+static int drm_dp_read_extended_dpcd_caps(struct drm_dp_aux *aux, + u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + u8 dpcd_ext[6]; + int ret; + + /* + * Prior to DP1.3 the bit represented by + * DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT was reserved. + * If it is set DP_DPCD_REV at 0000h could be at a value less than + * the true capability of the panel. The only way to check is to + * then compare 0000h and 2200h. + */ + if (!(dpcd[DP_TRAINING_AUX_RD_INTERVAL] & + DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT)) + return 0; + + ret = drm_dp_dpcd_read(aux, DP_DP13_DPCD_REV, &dpcd_ext, + sizeof(dpcd_ext)); + if (ret < 0) + return ret; + if (ret != sizeof(dpcd_ext)) + return -EIO; + + if (dpcd[DP_DPCD_REV] > dpcd_ext[DP_DPCD_REV]) { + DRM_DEBUG_KMS("%s: Extended DPCD rev less than base DPCD rev (%d > %d)\n", + aux->name, dpcd[DP_DPCD_REV], + dpcd_ext[DP_DPCD_REV]); + return 0; + } + + if (!memcmp(dpcd, dpcd_ext, sizeof(dpcd_ext))) + return 0; + + DRM_DEBUG_KMS("%s: Base DPCD: %*ph\n", + aux->name, DP_RECEIVER_CAP_SIZE, dpcd); + + memcpy(dpcd, dpcd_ext, sizeof(dpcd_ext)); + + return 0; +} + +/** + * drm_dp_read_dpcd_caps() - read DPCD caps and extended DPCD caps if + * available + * @aux: DisplayPort AUX channel + * @dpcd: Buffer to store the resulting DPCD in + * + * Attempts to read the base DPCD caps for @aux. Additionally, this function + * checks for and reads the extended DPRX caps (%DP_DP13_DPCD_REV) if + * present. + * + * Returns: %0 if the DPCD was read successfully, negative error code + * otherwise. + */ +int drm_dp_read_dpcd_caps(struct drm_dp_aux *aux, + u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + int ret; + + ret = drm_dp_dpcd_read(aux, DP_DPCD_REV, dpcd, DP_RECEIVER_CAP_SIZE); + if (ret < 0) + return ret; + if (ret != DP_RECEIVER_CAP_SIZE || dpcd[DP_DPCD_REV] == 0) + return -EIO; + + ret = drm_dp_read_extended_dpcd_caps(aux, dpcd); + if (ret < 0) + return ret; + + DRM_DEBUG_KMS("%s: DPCD: %*ph\n", + aux->name, DP_RECEIVER_CAP_SIZE, dpcd); + + return ret; +} +EXPORT_SYMBOL(drm_dp_read_dpcd_caps); + /** * drm_dp_downstream_read_info() - read DPCD downstream port info if available * @aux: DisplayPort AUX channel diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 4337321a3be4f..fb7872e2a0b93 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -4449,62 +4449,6 @@ intel_dp_link_down(struct intel_encoder *encoder, } }

-static void -intel_dp_extended_receiver_capabilities(struct intel_dp *intel_dp) -{ - struct drm_i915_private *i915 = dp_to_i915(intel_dp); - u8 dpcd_ext[6]; - - /* - * Prior to DP1.3 the bit represented by - * DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT was reserved. - * if it is set DP_DPCD_REV at 0000h could be at a value less than - * the true capability of the panel. The only way to check is to - * then compare 0000h and 2200h. - */ - if (!(intel_dp->dpcd[DP_TRAINING_AUX_RD_INTERVAL] & - DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT)) - return; - - if (drm_dp_dpcd_read(&intel_dp->aux, DP_DP13_DPCD_REV, - &dpcd_ext, sizeof(dpcd_ext)) != sizeof(dpcd_ext)) { - drm_err(&i915->drm, - "DPCD failed read at extended capabilities\n"); - return; - } - - if (intel_dp->dpcd[DP_DPCD_REV] > dpcd_ext[DP_DPCD_REV]) { - drm_dbg_kms(&i915->drm, - "DPCD extended DPCD rev less than base DPCD rev\n"); - return; - } - - if (!memcmp(intel_dp->dpcd, dpcd_ext, sizeof(dpcd_ext))) - return; - - drm_dbg_kms(&i915->drm, "Base DPCD: %*ph\n", - (int)sizeof(intel_dp->dpcd), intel_dp->dpcd); - - memcpy(intel_dp->dpcd, dpcd_ext, sizeof(dpcd_ext)); -} - -bool -intel_dp_read_dpcd(struct intel_dp *intel_dp) -{ - struct drm_i915_private *i915 = dp_to_i915(intel_dp); - - if (drm_dp_dpcd_read(&intel_dp->aux, 0x000, intel_dp->dpcd, - sizeof(intel_dp->dpcd)) < 0) - return false; /* aux transfer failed */ - - intel_dp_extended_receiver_capabilities(intel_dp); - - drm_dbg_kms(&i915->drm, "DPCD: %*ph\n", (int)sizeof(intel_dp->dpcd), - intel_dp->dpcd); - - return intel_dp->dpcd[DP_DPCD_REV] != 0; -} - bool intel_dp_get_colorimetry_status(struct intel_dp *intel_dp) { u8 dprx = 0; @@ -4563,7 +4507,7 @@ intel_edp_init_dpcd(struct intel_dp *intel_dp) /* this function is meant to be called only once */ drm_WARN_ON(&dev_priv->drm, intel_dp->dpcd[DP_DPCD_REV] != 0);

- if (!intel_dp_read_dpcd(intel_dp)) + if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd) != 0) return false;

drm_dp_read_desc(&intel_dp->aux, &intel_dp->desc, @@ -4650,7 +4594,7 @@ intel_dp_get_dpcd(struct intel_dp *intel_dp) { int ret;

- if (!intel_dp_read_dpcd(intel_dp)) + if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd)) return false;

/* diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h index b901ab850cbd9..0a3af3410d52e 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.h +++ b/drivers/gpu/drm/i915/display/intel_dp.h @@ -99,7 +99,6 @@ bool intel_dp_source_supports_hbr3(struct intel_dp *intel_dp); bool intel_dp_get_link_status(struct intel_dp *intel_dp, u8 *link_status);

-bool intel_dp_read_dpcd(struct intel_dp *intel_dp); bool intel_dp_get_colorimetry_status(struct intel_dp *intel_dp); int intel_dp_link_required(int pixel_clock, int bpp); int intel_dp_max_data_rate(int max_link_clock, int max_lanes); diff --git a/drivers/gpu/drm/i915/display/intel_lspcon.c b/drivers/gpu/drm/i915/display/intel_lspcon.c index b781bf4696443..dc1b35559afdf 100644 --- a/drivers/gpu/drm/i915/display/intel_lspcon.c +++ b/drivers/gpu/drm/i915/display/intel_lspcon.c @@ -571,7 +571,7 @@ bool lspcon_init(struct intel_digital_port *dig_port) return false; }

- if (!intel_dp_read_dpcd(dp)) { + if (drm_dp_read_dpcd_caps(&dp->aux, dp->dpcd) != 0) { DRM_ERROR("LSPCON DPCD read failed\n"); return false; } diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 0c141fc81aaa8..11649e93e5bb6 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -1607,6 +1607,9 @@ static inline ssize_t drm_dp_dpcd_writeb(struct drm_dp_aux *aux, return drm_dp_dpcd_write(aux, offset, &value, 1); }

+int drm_dp_read_dpcd_caps(struct drm_dp_aux *aux, + u8 dpcd[DP_RECEIVER_CAP_SIZE]); + int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux, u8 status[DP_LINK_STATUS_SIZE]);