[Intel-gfx] [PATCH] drm/drm_mst: Use Extended Base Receiver Capability DPCD space
[why] DP 1.4a spec madates that if DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT is set, Extended Base Receiver Capability DPCD space must be used. Without doing that, the three DPCD values that differ will be wrong, leading to incorrect or limited functionality. MST link rate, for example, could have a lower value. Also, Synaptics quirk wouldn't work out well when Extended DPCD was not read, resulting in no DSC for such hubs. [how] Modify MST topology manager to use the values from Extended DPCD where applicable. To prevent regression on the sources that have a lower maximum link rate capability than MAX_LINK_RATE from Extended DPCD, have the drivers supply maximum lane count and rate at initialization time. This also reverts 'commit 2dcab875e763 ("Revert "drm/dp_mst: Retrieve extended DPCD caps for topology manager"")', brining the change back to the original 'commit ad44c03208e4 ("drm/dp_mst: Retrieve extended DPCD caps for topology manager")'. Signed-off-by: Nikola Cornij --- .../display/amdgpu_dm/amdgpu_dm_mst_types.c | 5 +++ .../gpu/drm/amd/display/dc/core/dc_link_dp.c | 18 ++ drivers/gpu/drm/amd/display/dc/dc_link.h | 2 ++ drivers/gpu/drm/drm_dp_mst_topology.c | 33 --- drivers/gpu/drm/i915/display/intel_dp_mst.c | 6 +++- drivers/gpu/drm/nouveau/dispnv50/disp.c | 3 +- drivers/gpu/drm/radeon/radeon_dp_mst.c| 8 + include/drm/drm_dp_mst_helper.h | 12 ++- 8 files changed, 72 insertions(+), 15 deletions(-) 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 d62460b69d95..d038e3185afb 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 @@ -437,6 +437,8 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, struct amdgpu_dm_connector *aconnector, int link_index) { + struct dc_link_settings max_link_enc_cap = {0}; + aconnector->dm_dp_aux.aux.name = kasprintf(GFP_KERNEL, "AMDGPU DM aux hw bus %d", link_index); @@ -450,6 +452,7 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP) return; + dc_link_dp_get_max_link_enc_cap(aconnector->dc_link, &max_link_enc_cap); aconnector->mst_mgr.cbs = &dm_mst_cbs; drm_dp_mst_topology_mgr_init( &aconnector->mst_mgr, @@ -457,6 +460,8 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, &aconnector->dm_dp_aux.aux, 16, 4, + max_link_enc_cap.lane_count, + max_link_enc_cap.link_rate, aconnector->connector_id); drm_connector_attach_dp_subconnector_property(&aconnector->base); diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c index 3ff3d9e90983..afa43181dec6 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c @@ -1893,6 +1893,24 @@ bool dc_link_dp_sync_lt_end(struct dc_link *link, bool link_down) return true; } +bool dc_link_dp_get_max_link_enc_cap(const struct dc_link *link, struct dc_link_settings *max_link_enc_cap) +{ + if (!max_link_enc_cap) { + DC_LOG_ERROR("%s: Could not return max link encoder caps", __func__); + return false; + } + + if (link->link_enc->funcs->get_max_link_cap) { + link->link_enc->funcs->get_max_link_cap(link->link_enc, max_link_enc_cap); + return true; + } + + DC_LOG_ERROR("%s: Max link encoder caps unknown", __func__); + max_link_enc_cap->lane_count = 1; + max_link_enc_cap->link_rate = 6; + return false; +} + static struct dc_link_settings get_max_link_cap(struct dc_link *link) { struct dc_link_settings max_link_cap = {0}; diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h index 054bab45ee17..fc5622ffec3d 100644 --- a/drivers/gpu/drm/amd/display/dc/dc_link.h +++ b/drivers/gpu/drm/amd/display/dc/dc_link.h @@ -345,6 +345,8 @@ bool dc_link_dp_set_test_pattern( const unsigned char *p_custom_pattern, unsigned int cust_pattern_size); +bool dc_link_dp_get_max_link_enc_cap(const struct dc_link *link, struct dc_link_settings *max_link_enc_cap); + void dc_link_enable_hpd_filter(struct dc_link *link, bool enable); bool dc_link_is_dp_sink_present(struct dc_link *link); diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index de5124ce42cb..a86065c9a880 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers
[Intel-gfx] [PATCH] drm/drm_mst: Use Extended Base Receiver Capability DPCD space
[why] DP 1.4a spec madates that if DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT is set, Extended Base Receiver Capability DPCD space must be used. Without doing that, the three DPCD values that differ will be wrong, leading to incorrect or limited functionality. MST link rate, for example, could have a lower value or Synaptics quirk wouldn't work out well when Extended DPCD was not read, resulting in no DSC for such hubs. [how] Modify MST topology manager to use the values from Extended DPCD where applicable. To prevent regression on the sources that have lower maximum link rate capability than MAX_LINK_RATE from Extended DPCD, have the drivers supply maximum lane count and rate at initialization time. This also reverts 'commit 2dcab875e763 ("Revert "drm/dp_mst: Retrieve extended DPCD caps for topology manager"")', brining the change back to the original 'commit ad44c03208e4 ("drm/dp_mst: Retrieve extended DPCD caps for topology manager")'. Signed-off-by: Nikola Cornij --- .../display/amdgpu_dm/amdgpu_dm_mst_types.c | 5 +++ .../gpu/drm/amd/display/dc/core/dc_link_dp.c | 18 ++ drivers/gpu/drm/amd/display/dc/dc_link.h | 2 ++ drivers/gpu/drm/drm_dp_mst_topology.c | 33 --- drivers/gpu/drm/i915/display/intel_dp_mst.c | 6 +++- drivers/gpu/drm/nouveau/dispnv50/disp.c | 3 +- drivers/gpu/drm/radeon/radeon_dp_mst.c| 3 ++ include/drm/drm_dp_mst_helper.h | 12 ++- 8 files changed, 67 insertions(+), 15 deletions(-) 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 d62460b69d95..d038e3185afb 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 @@ -437,6 +437,8 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, struct amdgpu_dm_connector *aconnector, int link_index) { + struct dc_link_settings max_link_enc_cap = {0}; + aconnector->dm_dp_aux.aux.name = kasprintf(GFP_KERNEL, "AMDGPU DM aux hw bus %d", link_index); @@ -450,6 +452,7 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP) return; + dc_link_dp_get_max_link_enc_cap(aconnector->dc_link, &max_link_enc_cap); aconnector->mst_mgr.cbs = &dm_mst_cbs; drm_dp_mst_topology_mgr_init( &aconnector->mst_mgr, @@ -457,6 +460,8 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, &aconnector->dm_dp_aux.aux, 16, 4, + max_link_enc_cap.lane_count, + max_link_enc_cap.link_rate, aconnector->connector_id); drm_connector_attach_dp_subconnector_property(&aconnector->base); diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c index 3ff3d9e90983..afa43181dec6 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c @@ -1893,6 +1893,24 @@ bool dc_link_dp_sync_lt_end(struct dc_link *link, bool link_down) return true; } +bool dc_link_dp_get_max_link_enc_cap(const struct dc_link *link, struct dc_link_settings *max_link_enc_cap) +{ + if (!max_link_enc_cap) { + DC_LOG_ERROR("%s: Could not return max link encoder caps", __func__); + return false; + } + + if (link->link_enc->funcs->get_max_link_cap) { + link->link_enc->funcs->get_max_link_cap(link->link_enc, max_link_enc_cap); + return true; + } + + DC_LOG_ERROR("%s: Max link encoder caps unknown", __func__); + max_link_enc_cap->lane_count = 1; + max_link_enc_cap->link_rate = 6; + return false; +} + static struct dc_link_settings get_max_link_cap(struct dc_link *link) { struct dc_link_settings max_link_cap = {0}; diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h index 054bab45ee17..fc5622ffec3d 100644 --- a/drivers/gpu/drm/amd/display/dc/dc_link.h +++ b/drivers/gpu/drm/amd/display/dc/dc_link.h @@ -345,6 +345,8 @@ bool dc_link_dp_set_test_pattern( const unsigned char *p_custom_pattern, unsigned int cust_pattern_size); +bool dc_link_dp_get_max_link_enc_cap(const struct dc_link *link, struct dc_link_settings *max_link_enc_cap); + void dc_link_enable_hpd_filter(struct dc_link *link, bool enable); bool dc_link_is_dp_sink_present(struct dc_link *link); diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index de5124ce42cb..a86065c9a880 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/
Re: [Intel-gfx] [PATCH] drm/drm_mst: Use Extended Base Receiver Capability DPCD space
[AMD Official Use Only - Internal Distribution Only] Hi, drm/radeon/ part is still WIP (i.e. I doubt it'll work as is), but drm/i915 and drm/nouveau/ should be OK. Would it be possible to test those while I'm figuring out drm/radeon/ settings? I'm pretty sure the follow-up change would affect only drm/radeon/, i.e. no modifications in other parts of the code (unless found wrong in review, of course). I've tested drm/amd/ and it passes - I've confirmed the link and rate values make it all the way to drm_dp_mst_topology_mgr_set_mst(). Thanks, Nikola -Original Message- From: Cornij, Nikola Sent: Tuesday, April 27, 2021 5:29 PM To: amd-...@lists.freedesktop.org Cc: Pillai, Aurabindo ; Lipski, Mikita ; ly...@redhat.com; ville.syrj...@linux.intel.com; koba...@canonical.com; intel-gfx@lists.freedesktop.org; Cornij, Nikola Subject: [PATCH] drm/drm_mst: Use Extended Base Receiver Capability DPCD space [why] DP 1.4a spec madates that if DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT is set, Extended Base Receiver Capability DPCD space must be used. Without doing that, the three DPCD values that differ will be wrong, leading to incorrect or limited functionality. MST link rate, for example, could have a lower value or Synaptics quirk wouldn't work out well when Extended DPCD was not read, resulting in no DSC for such hubs. [how] Modify MST topology manager to use the values from Extended DPCD where applicable. To prevent regression on the sources that have lower maximum link rate capability than MAX_LINK_RATE from Extended DPCD, have the drivers supply maximum lane count and rate at initialization time. This also reverts the 2dcab875e763 (Revert "drm/dp_mst: Retrieve extended DPCD caps for topology manager), brining the change back to the original commit ad44c03208e4 (drm/dp_mst: Retrieve extended DPCD caps for topology manager). Signed-off-by: Nikola Cornij --- .../display/amdgpu_dm/amdgpu_dm_mst_types.c | 5 +++ .../gpu/drm/amd/display/dc/core/dc_link_dp.c | 17 ++ drivers/gpu/drm/amd/display/dc/dc_link.h | 2 ++ drivers/gpu/drm/drm_dp_mst_topology.c | 33 --- drivers/gpu/drm/i915/display/intel_dp_mst.c | 6 +++- drivers/gpu/drm/nouveau/dispnv50/disp.c | 3 +- drivers/gpu/drm/radeon/radeon_dp_mst.c| 3 ++ include/drm/drm_dp_mst_helper.h | 12 ++- 8 files changed, 66 insertions(+), 15 deletions(-) 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 d62460b69d95..d038e3185afb 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 @@ -437,6 +437,8 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, struct amdgpu_dm_connector *aconnector, int link_index) { +struct dc_link_settings max_link_enc_cap = {0}; + aconnector->dm_dp_aux.aux.name = kasprintf(GFP_KERNEL, "AMDGPU DM aux hw bus %d", link_index); @@ -450,6 +452,7 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP) return; +dc_link_dp_get_max_link_enc_cap(aconnector->dc_link, +&max_link_enc_cap); aconnector->mst_mgr.cbs = &dm_mst_cbs; drm_dp_mst_topology_mgr_init( &aconnector->mst_mgr, @@ -457,6 +460,8 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, &aconnector->dm_dp_aux.aux, 16, 4, +max_link_enc_cap.lane_count, +max_link_enc_cap.link_rate, aconnector->connector_id); drm_connector_attach_dp_subconnector_property(&aconnector->base); diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c index 3ff3d9e90983..18a0b84e9869 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c @@ -1893,6 +1893,23 @@ bool dc_link_dp_sync_lt_end(struct dc_link *link, bool link_down) return true; } +bool dc_link_dp_get_max_link_enc_cap(const struct dc_link *link, struct +dc_link_settings *max_link_enc_cap) { +if (max_link_enc_cap == NULL) { +DC_LOG_ERROR("%s: Could not return max link encoder caps", __func__); +} + +if (link->link_enc->funcs->get_max_link_cap) { +link->link_enc->funcs->get_max_link_cap(link->link_enc, max_link_enc_cap); +return true; +} + +DC_LOG_ERROR("%s: Max link encoder caps unknown", __func__); +max_link_enc_cap->lane_count = 1; +max_link_enc_cap->link_rate = 6; +return false; +} + static struct dc_link_settings get_max_link_cap(struct dc_link *link) { struct dc_link_settings max_link_cap = {0}; diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h index 054bab45ee17..fc5622ffec3d 100644 --- a/drivers/gpu/drm/amd/display/dc/dc_link.h +++ b/drivers/gpu/drm/amd/display/dc/dc_link.h @@ -345,6 +345,8 @@ bool dc_link_dp_set_test_pattern( const u
[Intel-gfx] [PATCH] drm/drm_mst: Use Extended Base Receiver Capability DPCD space
[why] DP 1.4a spec madates that if DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT is set, Extended Base Receiver Capability DPCD space must be used. Without doing that, the three DPCD values that differ will be wrong, leading to incorrect or limited functionality. MST link rate, for example, could have a lower value or Synaptics quirk wouldn't work out well when Extended DPCD was not read, resulting in no DSC for such hubs. [how] Modify MST topology manager to use the values from Extended DPCD where applicable. To prevent regression on the sources that have lower maximum link rate capability than MAX_LINK_RATE from Extended DPCD, have the drivers supply maximum lane count and rate at initialization time. This also reverts the 2dcab875e763 (Revert "drm/dp_mst: Retrieve extended DPCD caps for topology manager), brining the change back to the original commit ad44c03208e4 (drm/dp_mst: Retrieve extended DPCD caps for topology manager). Signed-off-by: Nikola Cornij --- .../display/amdgpu_dm/amdgpu_dm_mst_types.c | 5 +++ .../gpu/drm/amd/display/dc/core/dc_link_dp.c | 17 ++ drivers/gpu/drm/amd/display/dc/dc_link.h | 2 ++ drivers/gpu/drm/drm_dp_mst_topology.c | 33 --- drivers/gpu/drm/i915/display/intel_dp_mst.c | 6 +++- drivers/gpu/drm/nouveau/dispnv50/disp.c | 3 +- drivers/gpu/drm/radeon/radeon_dp_mst.c| 3 ++ include/drm/drm_dp_mst_helper.h | 12 ++- 8 files changed, 66 insertions(+), 15 deletions(-) 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 d62460b69d95..d038e3185afb 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 @@ -437,6 +437,8 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, struct amdgpu_dm_connector *aconnector, int link_index) { + struct dc_link_settings max_link_enc_cap = {0}; + aconnector->dm_dp_aux.aux.name = kasprintf(GFP_KERNEL, "AMDGPU DM aux hw bus %d", link_index); @@ -450,6 +452,7 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP) return; + dc_link_dp_get_max_link_enc_cap(aconnector->dc_link, &max_link_enc_cap); aconnector->mst_mgr.cbs = &dm_mst_cbs; drm_dp_mst_topology_mgr_init( &aconnector->mst_mgr, @@ -457,6 +460,8 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, &aconnector->dm_dp_aux.aux, 16, 4, + max_link_enc_cap.lane_count, + max_link_enc_cap.link_rate, aconnector->connector_id); drm_connector_attach_dp_subconnector_property(&aconnector->base); diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c index 3ff3d9e90983..18a0b84e9869 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c @@ -1893,6 +1893,23 @@ bool dc_link_dp_sync_lt_end(struct dc_link *link, bool link_down) return true; } +bool dc_link_dp_get_max_link_enc_cap(const struct dc_link *link, struct dc_link_settings *max_link_enc_cap) +{ + if (max_link_enc_cap == NULL) { + DC_LOG_ERROR("%s: Could not return max link encoder caps", __func__); + } + + if (link->link_enc->funcs->get_max_link_cap) { + link->link_enc->funcs->get_max_link_cap(link->link_enc, max_link_enc_cap); + return true; + } + + DC_LOG_ERROR("%s: Max link encoder caps unknown", __func__); + max_link_enc_cap->lane_count = 1; + max_link_enc_cap->link_rate = 6; + return false; +} + static struct dc_link_settings get_max_link_cap(struct dc_link *link) { struct dc_link_settings max_link_cap = {0}; diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h index 054bab45ee17..fc5622ffec3d 100644 --- a/drivers/gpu/drm/amd/display/dc/dc_link.h +++ b/drivers/gpu/drm/amd/display/dc/dc_link.h @@ -345,6 +345,8 @@ bool dc_link_dp_set_test_pattern( const unsigned char *p_custom_pattern, unsigned int cust_pattern_size); +bool dc_link_dp_get_max_link_enc_cap(const struct dc_link *link, struct dc_link_settings *max_link_enc_cap); + void dc_link_enable_hpd_filter(struct dc_link *link, bool enable); bool dc_link_is_dp_sink_present(struct dc_link *link); diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index de5124ce42cb..36e4155f048c 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -3693,18 +