[PATCH 1/4] drm: Remove slot checks in dp mst topology during commit

[PATCH 1/4] drm: Remove slot checks in dp mst topology during commit

[Bhawanpreet Lakha]

This code path is used during commit, and we dont expect things to fail
during the commit stage, so remove this.

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
---
 drivers/gpu/drm/drm_dp_mst_topology.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index ad0795afc21c..5ab3b3a46e89 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -4332,10 +4332,6 @@ static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 {
 	int ret;
 
-	/* max. time slots - one slot for MTP header */
-	if (slots > 63)
-		return -ENOSPC;
-
 	vcpi->pbn = pbn;
 	vcpi->aligned_pbn = slots * mgr->pbn_div;
 	vcpi->num_slots = slots;
@@ -4538,7 +4534,7 @@ bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 
 	ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn, slots);
 	if (ret) {
-		drm_dbg_kms(mgr->dev, "failed to init vcpi slots=%d max=63 ret=%d\n",
+		drm_dbg_kms(mgr->dev, "failed to init vcpi slots=%d ret=%d\n",
 			    DIV_ROUND_UP(pbn, mgr->pbn_div), ret);
 		drm_dp_mst_topology_put_port(port);
 		goto out;
-- 
2.25.1

[Intel-gfx] [PATCH 1/4] drm: Remove slot checks in dp mst topology during commit

[Bhawanpreet Lakha]

This code path is used during commit, and we dont expect things to fail
during the commit stage, so remove this.

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
---
 drivers/gpu/drm/drm_dp_mst_topology.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index ad0795afc21c..5ab3b3a46e89 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -4332,10 +4332,6 @@ static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 {
 	int ret;
 
-	/* max. time slots - one slot for MTP header */
-	if (slots > 63)
-		return -ENOSPC;
-
 	vcpi->pbn = pbn;
 	vcpi->aligned_pbn = slots * mgr->pbn_div;
 	vcpi->num_slots = slots;
@@ -4538,7 +4534,7 @@ bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 
 	ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn, slots);
 	if (ret) {
-		drm_dbg_kms(mgr->dev, "failed to init vcpi slots=%d max=63 ret=%d\n",
+		drm_dbg_kms(mgr->dev, "failed to init vcpi slots=%d ret=%d\n",
 			    DIV_ROUND_UP(pbn, mgr->pbn_div), ret);
 		drm_dp_mst_topology_put_port(port);
 		goto out;
-- 
2.25.1

[PATCH 2/4] drm: Update MST First Link Slot Information Based on Encoding Format

[Bhawanpreet Lakha]

8b/10b encoding format requires to reserve the first slot for
recording metadata. Real data transmission starts from the second slot,
with a total of available 63 slots available.

In 128b/132b encoding format, metadata is transmitted separately
in LLCP packet before MTP. Real data transmission starts from
the first slot, with a total of 64 slots available.

v2:
* Move total/start slots to mst_state, and copy it to mst_mgr in
atomic_check

v3:
* Only keep the slot info on the mst_state
* add a start_slot parameter to the payload function, to facilitate non
  atomic drivers (this is a temporary workaround and should be removed when
  we are moving out the non atomic driver helpers)

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
---
 .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  2 +-
 drivers/gpu/drm/drm_dp_mst_topology.c         | 34 ++++++++++++++++---
 drivers/gpu/drm/i915/display/intel_dp_mst.c   |  4 +--
 drivers/gpu/drm/nouveau/dispnv50/disp.c       |  2 +-
 drivers/gpu/drm/radeon/radeon_dp_mst.c        |  4 +--
 include/drm/drm_dp_mst_helper.h               |  5 ++-
 6 files changed, 40 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index ff0f91c93ba4..6169488e2011 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -251,7 +251,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 	}
 
 	/* It's OK for this to fail */
-	drm_dp_update_payload_part1(mst_mgr);
+	drm_dp_update_payload_part1(mst_mgr, 1);
 
 	/* mst_mgr->->payloads are VC payload notify MST branch using DPCD or
 	 * AUX message. The sequence is slot 1-63 allocated sequence for each
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 5ab3b3a46e89..d188a5269070 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -3353,6 +3353,9 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
 /**
  * drm_dp_update_payload_part1() - Execute payload update part 1
  * @mgr: manager to use.
+ * @start_slot: this is the cur slot
+ *  NOTE: start_slot is a temporary workaround for non-atomic drivers,
+ *  this will be removed when non-atomic mst helpers are moved out of the helper
  *
  * This iterates over all proposed virtual channels, and tries to
  * allocate space in the link for them. For 0->slots transitions,
@@ -3363,12 +3366,12 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
  * after calling this the driver should generate ACT and payload
  * packets.
  */
-int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot)
 {
 	struct drm_dp_payload req_payload;
 	struct drm_dp_mst_port *port;
 	int i, j;
-	int cur_slots = 1;
+	int cur_slots = start_slot;
 	bool skip;
 
 	mutex_lock(&mgr->payload_lock);
@@ -4503,6 +4506,26 @@ int drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
 }
 EXPORT_SYMBOL(drm_dp_atomic_release_vcpi_slots);
 
+/**
+ * drm_dp_mst_update_slots() - updates the slot info depending on the DP ecoding format
+ * @mst_state: mst_state to update
+ * @link_ecoding_cap: the ecoding format on the link
+ */
+void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_ecoding_cap)
+{
+	if (link_ecoding_cap == DP_CAP_ANSI_128B132B) {
+		mst_state->total_avail_slots = 64;
+		mst_state->start_slot = 0;
+	} else {
+		mst_state->total_avail_slots = 63;
+		mst_state->start_slot = 1;
+	}
+
+	DRM_DEBUG_KMS("%s ecoding format on mst_state 0x%p\n",
+			(link_ecoding_cap == DP_CAP_ANSI_128B132B) ? "128b/132b":"8b/10b", mst_state->mgr);
+}
+EXPORT_SYMBOL(drm_dp_mst_update_slots);
+
 /**
  * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
  * @mgr: manager for this port
@@ -5222,7 +5245,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
 					 struct drm_dp_mst_topology_state *mst_state)
 {
 	struct drm_dp_vcpi_allocation *vcpi;
-	int avail_slots = 63, payload_count = 0;
+	int avail_slots = mst_state->total_avail_slots, payload_count = 0;
 
 	list_for_each_entry(vcpi, &mst_state->vcpis, next) {
 		/* Releasing VCPI is always OK-even if the port is gone */
@@ -5251,7 +5274,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
 		}
 	}
 	drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p VCPI avail=%d used=%d\n",
-		       mgr, mst_state, avail_slots, 63 - avail_slots);
+		       mgr, mst_state, avail_slots, mst_state->total_avail_slots - avail_slots);
 
 	return 0;
 }
@@ -5528,6 +5551,9 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
 	if (mst_state == NULL)
 		return -ENOMEM;
 
+	mst_state->total_avail_slots = 63;
+	mst_state->start_slot = 1;
+
 	mst_state->mgr = mgr;
 	INIT_LIST_HEAD(&mst_state->vcpis);
 
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index b170e272bdee..d3a24189a12c 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -368,7 +368,7 @@ static void intel_mst_disable_dp(struct intel_atomic_state *state,
 
 	drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, connector->port);
 
-	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
+	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
 	if (ret) {
 		drm_dbg_kms(&i915->drm, "failed to update payload %d\n", ret);
 	}
@@ -516,7 +516,7 @@ static void intel_mst_pre_enable_dp(struct intel_atomic_state *state,
 
 	intel_dp->active_mst_links++;
 
-	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
+	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
 
 	/*
 	 * Before Gen 12 this is not done as part of
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index f949767698fc..6c8c59c26dbf 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -1413,7 +1413,7 @@ nv50_mstm_prepare(struct nv50_mstm *mstm)
 	int ret;
 
 	NV_ATOMIC(drm, "%s: mstm prepare\n", mstm->outp->base.base.name);
-	ret = drm_dp_update_payload_part1(&mstm->mgr);
+	ret = drm_dp_update_payload_part1(&mstm->mgr, 1);
 
 	drm_for_each_encoder(encoder, mstm->outp->base.base.dev) {
 		if (encoder->encoder_type == DRM_MODE_ENCODER_DPMST) {
diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c
index ec867fa880a4..751c2c075e09 100644
--- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
+++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
@@ -423,7 +423,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
 		drm_dp_mst_allocate_vcpi(&radeon_connector->mst_port->mst_mgr,
 					 radeon_connector->port,
 					 mst_enc->pbn, slots);
-		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
+		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
 
 		radeon_dp_mst_set_be_cntl(primary, mst_enc,
 					  radeon_connector->mst_port->hpd.hpd, true);
@@ -452,7 +452,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
 			return;
 
 		drm_dp_mst_reset_vcpi_slots(&radeon_connector->mst_port->mst_mgr, mst_enc->port);
-		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
+		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
 
 		drm_dp_check_act_status(&radeon_connector->mst_port->mst_mgr);
 		/* and this can also fail */
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index ddb9231d0309..3207b49586fc 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -554,6 +554,8 @@ struct drm_dp_mst_topology_state {
 	struct drm_private_state base;
 	struct list_head vcpis;
 	struct drm_dp_mst_topology_mgr *mgr;
+	u8 total_avail_slots;
+	u8 start_slot;
 };
 
 #define to_dp_mst_topology_mgr(x) container_of(x, struct drm_dp_mst_topology_mgr, base)
@@ -806,6 +808,7 @@ int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp
 
 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
 
+void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_ecoding_cap);
 
 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 				struct drm_dp_mst_port *port);
@@ -815,7 +818,7 @@ int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
 			   int pbn);
 
 
-int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot);
 
 
 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);
-- 
2.25.1

[Intel-gfx] [PATCH 2/4] drm: Update MST First Link Slot Information Based on Encoding Format

[Bhawanpreet Lakha]

8b/10b encoding format requires to reserve the first slot for
recording metadata. Real data transmission starts from the second slot,
with a total of available 63 slots available.

In 128b/132b encoding format, metadata is transmitted separately
in LLCP packet before MTP. Real data transmission starts from
the first slot, with a total of 64 slots available.

v2:
* Move total/start slots to mst_state, and copy it to mst_mgr in
atomic_check

v3:
* Only keep the slot info on the mst_state
* add a start_slot parameter to the payload function, to facilitate non
  atomic drivers (this is a temporary workaround and should be removed when
  we are moving out the non atomic driver helpers)

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
---
 .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  2 +-
 drivers/gpu/drm/drm_dp_mst_topology.c         | 34 ++++++++++++++++---
 drivers/gpu/drm/i915/display/intel_dp_mst.c   |  4 +--
 drivers/gpu/drm/nouveau/dispnv50/disp.c       |  2 +-
 drivers/gpu/drm/radeon/radeon_dp_mst.c        |  4 +--
 include/drm/drm_dp_mst_helper.h               |  5 ++-
 6 files changed, 40 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index ff0f91c93ba4..6169488e2011 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -251,7 +251,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 	}
 
 	/* It's OK for this to fail */
-	drm_dp_update_payload_part1(mst_mgr);
+	drm_dp_update_payload_part1(mst_mgr, 1);
 
 	/* mst_mgr->->payloads are VC payload notify MST branch using DPCD or
 	 * AUX message. The sequence is slot 1-63 allocated sequence for each
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 5ab3b3a46e89..d188a5269070 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -3353,6 +3353,9 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
 /**
  * drm_dp_update_payload_part1() - Execute payload update part 1
  * @mgr: manager to use.
+ * @start_slot: this is the cur slot
+ *  NOTE: start_slot is a temporary workaround for non-atomic drivers,
+ *  this will be removed when non-atomic mst helpers are moved out of the helper
  *
  * This iterates over all proposed virtual channels, and tries to
  * allocate space in the link for them. For 0->slots transitions,
@@ -3363,12 +3366,12 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
  * after calling this the driver should generate ACT and payload
  * packets.
  */
-int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot)
 {
 	struct drm_dp_payload req_payload;
 	struct drm_dp_mst_port *port;
 	int i, j;
-	int cur_slots = 1;
+	int cur_slots = start_slot;
 	bool skip;
 
 	mutex_lock(&mgr->payload_lock);
@@ -4503,6 +4506,26 @@ int drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
 }
 EXPORT_SYMBOL(drm_dp_atomic_release_vcpi_slots);
 
+/**
+ * drm_dp_mst_update_slots() - updates the slot info depending on the DP ecoding format
+ * @mst_state: mst_state to update
+ * @link_ecoding_cap: the ecoding format on the link
+ */
+void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_ecoding_cap)
+{
+	if (link_ecoding_cap == DP_CAP_ANSI_128B132B) {
+		mst_state->total_avail_slots = 64;
+		mst_state->start_slot = 0;
+	} else {
+		mst_state->total_avail_slots = 63;
+		mst_state->start_slot = 1;
+	}
+
+	DRM_DEBUG_KMS("%s ecoding format on mst_state 0x%p\n",
+			(link_ecoding_cap == DP_CAP_ANSI_128B132B) ? "128b/132b":"8b/10b", mst_state->mgr);
+}
+EXPORT_SYMBOL(drm_dp_mst_update_slots);
+
 /**
  * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
  * @mgr: manager for this port
@@ -5222,7 +5245,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
 					 struct drm_dp_mst_topology_state *mst_state)
 {
 	struct drm_dp_vcpi_allocation *vcpi;
-	int avail_slots = 63, payload_count = 0;
+	int avail_slots = mst_state->total_avail_slots, payload_count = 0;
 
 	list_for_each_entry(vcpi, &mst_state->vcpis, next) {
 		/* Releasing VCPI is always OK-even if the port is gone */
@@ -5251,7 +5274,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
 		}
 	}
 	drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p VCPI avail=%d used=%d\n",
-		       mgr, mst_state, avail_slots, 63 - avail_slots);
+		       mgr, mst_state, avail_slots, mst_state->total_avail_slots - avail_slots);
 
 	return 0;
 }
@@ -5528,6 +5551,9 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
 	if (mst_state == NULL)
 		return -ENOMEM;
 
+	mst_state->total_avail_slots = 63;
+	mst_state->start_slot = 1;
+
 	mst_state->mgr = mgr;
 	INIT_LIST_HEAD(&mst_state->vcpis);
 
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index b170e272bdee..d3a24189a12c 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -368,7 +368,7 @@ static void intel_mst_disable_dp(struct intel_atomic_state *state,
 
 	drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, connector->port);
 
-	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
+	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
 	if (ret) {
 		drm_dbg_kms(&i915->drm, "failed to update payload %d\n", ret);
 	}
@@ -516,7 +516,7 @@ static void intel_mst_pre_enable_dp(struct intel_atomic_state *state,
 
 	intel_dp->active_mst_links++;
 
-	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
+	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
 
 	/*
 	 * Before Gen 12 this is not done as part of
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index f949767698fc..6c8c59c26dbf 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -1413,7 +1413,7 @@ nv50_mstm_prepare(struct nv50_mstm *mstm)
 	int ret;
 
 	NV_ATOMIC(drm, "%s: mstm prepare\n", mstm->outp->base.base.name);
-	ret = drm_dp_update_payload_part1(&mstm->mgr);
+	ret = drm_dp_update_payload_part1(&mstm->mgr, 1);
 
 	drm_for_each_encoder(encoder, mstm->outp->base.base.dev) {
 		if (encoder->encoder_type == DRM_MODE_ENCODER_DPMST) {
diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c
index ec867fa880a4..751c2c075e09 100644
--- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
+++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
@@ -423,7 +423,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
 		drm_dp_mst_allocate_vcpi(&radeon_connector->mst_port->mst_mgr,
 					 radeon_connector->port,
 					 mst_enc->pbn, slots);
-		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
+		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
 
 		radeon_dp_mst_set_be_cntl(primary, mst_enc,
 					  radeon_connector->mst_port->hpd.hpd, true);
@@ -452,7 +452,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
 			return;
 
 		drm_dp_mst_reset_vcpi_slots(&radeon_connector->mst_port->mst_mgr, mst_enc->port);
-		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
+		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
 
 		drm_dp_check_act_status(&radeon_connector->mst_port->mst_mgr);
 		/* and this can also fail */
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index ddb9231d0309..3207b49586fc 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -554,6 +554,8 @@ struct drm_dp_mst_topology_state {
 	struct drm_private_state base;
 	struct list_head vcpis;
 	struct drm_dp_mst_topology_mgr *mgr;
+	u8 total_avail_slots;
+	u8 start_slot;
 };
 
 #define to_dp_mst_topology_mgr(x) container_of(x, struct drm_dp_mst_topology_mgr, base)
@@ -806,6 +808,7 @@ int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp
 
 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
 
+void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_ecoding_cap);
 
 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 				struct drm_dp_mst_port *port);
@@ -815,7 +818,7 @@ int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
 			   int pbn);
 
 
-int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot);
 
 
 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);
-- 
2.25.1

[PATCH 3/4] drm/amd/display: Add DP 2.0 MST DC Support

[Bhawanpreet Lakha]

From: Fangzhi Zuo <Jerry.Zuo@amd.com>

Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc.c      |  14 +
 drivers/gpu/drm/amd/display/dc/core/dc_link.c | 280 ++++++++++++++++++
 .../gpu/drm/amd/display/dc/core/dc_link_dp.c  |  19 ++
 drivers/gpu/drm/amd/display/dc/dc_link.h      |   7 +
 drivers/gpu/drm/amd/display/dc/dc_stream.h    |  13 +
 5 files changed, 333 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index 8be04be19124..935a50d6e933 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -2354,6 +2354,11 @@ static enum surface_update_type check_update_surfaces_for_stream(
 		if (stream_update->dsc_config)
 			su_flags->bits.dsc_changed = 1;
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		if (stream_update->mst_bw_update)
+			su_flags->bits.mst_bw = 1;
+#endif
+
 		if (su_flags->raw != 0)
 			overall_type = UPDATE_TYPE_FULL;
 
@@ -2731,6 +2736,15 @@ static void commit_planes_do_stream_update(struct dc *dc,
 			if (stream_update->dsc_config)
 				dp_update_dsc_config(pipe_ctx);
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+			if (stream_update->mst_bw_update) {
+				if (stream_update->mst_bw_update->is_increase)
+					dc_link_increase_mst_payload(pipe_ctx, stream_update->mst_bw_update->mst_stream_bw);
+				else
+					dc_link_reduce_mst_payload(pipe_ctx, stream_update->mst_bw_update->mst_stream_bw);
+			}
+#endif
+
 			if (stream_update->pending_test_pattern) {
 				dc_link_dp_set_test_pattern(stream->link,
 					stream->test_pattern.type,
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index e5d6cbd7ea78..b23972b6a27c 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -3232,6 +3232,9 @@ static struct fixed31_32 get_pbn_from_timing(struct pipe_ctx *pipe_ctx)
 static void update_mst_stream_alloc_table(
 	struct dc_link *link,
 	struct stream_encoder *stream_enc,
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	struct hpo_dp_stream_encoder *hpo_dp_stream_enc, // TODO: Rename stream_enc to dio_stream_enc?
+#endif
 	const struct dp_mst_stream_allocation_table *proposed_table)
 {
 	struct link_mst_stream_allocation work_table[MAX_CONTROLLER_NUM] = { 0 };
@@ -3267,6 +3270,9 @@ static void update_mst_stream_alloc_table(
 			work_table[i].slot_count =
 				proposed_table->stream_allocations[i].slot_count;
 			work_table[i].stream_enc = stream_enc;
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+			work_table[i].hpo_dp_stream_enc = hpo_dp_stream_enc;
+#endif
 		}
 	}
 
@@ -3389,6 +3395,10 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 	struct dc_link *link = stream->link;
 	struct link_encoder *link_encoder = NULL;
 	struct stream_encoder *stream_encoder = pipe_ctx->stream_res.stream_enc;
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	struct hpo_dp_link_encoder *hpo_dp_link_encoder = link->hpo_dp_link_enc;
+	struct hpo_dp_stream_encoder *hpo_dp_stream_encoder = pipe_ctx->stream_res.hpo_dp_stream_enc;
+#endif
 	struct dp_mst_stream_allocation_table proposed_table = {0};
 	struct fixed31_32 avg_time_slots_per_mtp;
 	struct fixed31_32 pbn;
@@ -3416,7 +3426,14 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 		&proposed_table,
 		true)) {
 		update_mst_stream_alloc_table(
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+					link,
+					pipe_ctx->stream_res.stream_enc,
+					pipe_ctx->stream_res.hpo_dp_stream_enc,
+					&proposed_table);
+#else
 					link, pipe_ctx->stream_res.stream_enc, &proposed_table);
+#endif
 	}
 	else
 		DC_LOG_WARNING("Failed to update"
@@ -3430,6 +3447,20 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 			link->mst_stream_alloc_table.stream_count);
 
 	for (i = 0; i < MAX_CONTROLLER_NUM; i++) {
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		DC_LOG_MST("stream_enc[%d]: %p      "
+		"stream[%d].hpo_dp_stream_enc: %p      "
+		"stream[%d].vcp_id: %d      "
+		"stream[%d].slot_count: %d\n",
+		i,
+		(void *) link->mst_stream_alloc_table.stream_allocations[i].stream_enc,
+		i,
+		(void *) link->mst_stream_alloc_table.stream_allocations[i].hpo_dp_stream_enc,
+		i,
+		link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
+		i,
+		link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+#else
 		DC_LOG_MST("stream_enc[%d]: %p      "
 		"stream[%d].vcp_id: %d      "
 		"stream[%d].slot_count: %d\n",
@@ -3439,14 +3470,30 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 		link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
 		i,
 		link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+#endif
 	}
 
 	ASSERT(proposed_table.stream_count > 0);
 
 	/* program DP source TX for payload */
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	switch (dp_get_link_encoding_format(&link->cur_link_settings)) {
+	case DP_8b_10b_ENCODING:
+		link_encoder->funcs->update_mst_stream_allocation_table(
+			link_encoder,
+			&link->mst_stream_alloc_table);
+		break;
+	case DP_128b_132b_ENCODING:
+		hpo_dp_link_encoder->funcs->update_stream_allocation_table(
+				hpo_dp_link_encoder,
+				&link->mst_stream_alloc_table);
+		break;
+	}
+#else
 	link_encoder->funcs->update_mst_stream_allocation_table(
 		link_encoder,
 		&link->mst_stream_alloc_table);
+#endif
 
 	/* send down message */
 	ret = dm_helpers_dp_mst_poll_for_allocation_change_trigger(
@@ -3469,13 +3516,188 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 	pbn = get_pbn_from_timing(pipe_ctx);
 	avg_time_slots_per_mtp = dc_fixpt_div(pbn, pbn_per_slot);
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	switch (dp_get_link_encoding_format(&link->cur_link_settings)) {
+	case DP_8b_10b_ENCODING:
+		stream_encoder->funcs->set_throttled_vcp_size(
+			stream_encoder,
+			avg_time_slots_per_mtp);
+		break;
+	case DP_128b_132b_ENCODING:
+		hpo_dp_link_encoder->funcs->set_throttled_vcp_size(
+				hpo_dp_link_encoder,
+				hpo_dp_stream_encoder->inst,
+				avg_time_slots_per_mtp);
+		break;
+	}
+#else
 	stream_encoder->funcs->set_throttled_vcp_size(
 		stream_encoder,
 		avg_time_slots_per_mtp);
+#endif
+
+	return DC_OK;
+
+}
+
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+enum dc_status dc_link_reduce_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t bw_in_kbps)
+{
+	struct dc_stream_state *stream = pipe_ctx->stream;
+	struct dc_link *link = stream->link;
+	struct fixed31_32 avg_time_slots_per_mtp;
+	struct fixed31_32 pbn;
+	struct fixed31_32 pbn_per_slot;
+	struct link_encoder *link_encoder = link->link_enc;
+	struct stream_encoder *stream_encoder = pipe_ctx->stream_res.stream_enc;
+	struct dp_mst_stream_allocation_table proposed_table = {0};
+	uint8_t i;
+	enum act_return_status ret;
+	DC_LOGGER_INIT(link->ctx->logger);
+
+	/* decrease throttled vcp size */
+	pbn_per_slot = get_pbn_per_slot(stream);
+	pbn = get_pbn_from_bw_in_kbps(bw_in_kbps);
+	avg_time_slots_per_mtp = dc_fixpt_div(pbn, pbn_per_slot);
+
+	stream_encoder->funcs->set_throttled_vcp_size(
+				stream_encoder,
+				avg_time_slots_per_mtp);
+
+	/* send ALLOCATE_PAYLOAD sideband message with updated pbn */
+	dm_helpers_dp_mst_send_payload_allocation(
+			stream->ctx,
+			stream,
+			true);
+
+	/* notify immediate branch device table update */
+	if (dm_helpers_dp_mst_write_payload_allocation_table(
+			stream->ctx,
+			stream,
+			&proposed_table,
+			true)) {
+		/* update mst stream allocation table software state */
+		update_mst_stream_alloc_table(
+				link,
+				pipe_ctx->stream_res.stream_enc,
+				pipe_ctx->stream_res.hpo_dp_stream_enc,
+				&proposed_table);
+	} else {
+		DC_LOG_WARNING("Failed to update"
+				"MST allocation table for"
+				"pipe idx:%d\n",
+				pipe_ctx->pipe_idx);
+	}
+
+	DC_LOG_MST("%s  "
+			"stream_count: %d: \n ",
+			__func__,
+			link->mst_stream_alloc_table.stream_count);
+
+	for (i = 0; i < MAX_CONTROLLER_NUM; i++) {
+		DC_LOG_MST("stream_enc[%d]: %p      "
+				"stream[%d].vcp_id: %d      "
+				"stream[%d].slot_count: %d\n",
+				i,
+				(void *) link->mst_stream_alloc_table.stream_allocations[i].stream_enc,
+				i,
+				link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
+				i,
+				link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+	}
+
+	ASSERT(proposed_table.stream_count > 0);
+
+	/* update mst stream allocation table hardware state */
+	link_encoder->funcs->update_mst_stream_allocation_table(
+			link_encoder,
+			&link->mst_stream_alloc_table);
+
+	/* poll for immediate branch device ACT handled */
+	ret = dm_helpers_dp_mst_poll_for_allocation_change_trigger(
+			stream->ctx,
+			stream);
 
 	return DC_OK;
+}
+
+enum dc_status dc_link_increase_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t bw_in_kbps)
+{
+	struct dc_stream_state *stream = pipe_ctx->stream;
+	struct dc_link *link = stream->link;
+	struct fixed31_32 avg_time_slots_per_mtp;
+	struct fixed31_32 pbn;
+	struct fixed31_32 pbn_per_slot;
+	struct link_encoder *link_encoder = link->link_enc;
+	struct stream_encoder *stream_encoder = pipe_ctx->stream_res.stream_enc;
+	struct dp_mst_stream_allocation_table proposed_table = {0};
+	uint8_t i;
+	enum act_return_status ret;
+	DC_LOGGER_INIT(link->ctx->logger);
+
+	/* notify immediate branch device table update */
+	if (dm_helpers_dp_mst_write_payload_allocation_table(
+				stream->ctx,
+				stream,
+				&proposed_table,
+				true)) {
+		/* update mst stream allocation table software state */
+		update_mst_stream_alloc_table(
+				link,
+				pipe_ctx->stream_res.stream_enc,
+				pipe_ctx->stream_res.hpo_dp_stream_enc,
+				&proposed_table);
+	}
+
+	DC_LOG_MST("%s  "
+			"stream_count: %d: \n ",
+			__func__,
+			link->mst_stream_alloc_table.stream_count);
+
+	for (i = 0; i < MAX_CONTROLLER_NUM; i++) {
+		DC_LOG_MST("stream_enc[%d]: %p      "
+				"stream[%d].vcp_id: %d      "
+				"stream[%d].slot_count: %d\n",
+				i,
+				(void *) link->mst_stream_alloc_table.stream_allocations[i].stream_enc,
+				i,
+				link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
+				i,
+				link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+	}
+
+	ASSERT(proposed_table.stream_count > 0);
+
+	/* update mst stream allocation table hardware state */
+	link_encoder->funcs->update_mst_stream_allocation_table(
+			link_encoder,
+			&link->mst_stream_alloc_table);
+
+	/* poll for immediate branch device ACT handled */
+	ret = dm_helpers_dp_mst_poll_for_allocation_change_trigger(
+			stream->ctx,
+			stream);
+
+	if (ret != ACT_LINK_LOST) {
+		/* send ALLOCATE_PAYLOAD sideband message with updated pbn */
+		dm_helpers_dp_mst_send_payload_allocation(
+				stream->ctx,
+				stream,
+				true);
+	}
+
+	/* increase throttled vcp size */
+	pbn = get_pbn_from_bw_in_kbps(bw_in_kbps);
+	pbn_per_slot = get_pbn_per_slot(stream);
+	avg_time_slots_per_mtp = dc_fixpt_div(pbn, pbn_per_slot);
+
+	stream_encoder->funcs->set_throttled_vcp_size(
+				stream_encoder,
+				avg_time_slots_per_mtp);
 
+	return DC_OK;
 }
+#endif
 
 static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 {
@@ -3483,6 +3705,10 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 	struct dc_link *link = stream->link;
 	struct link_encoder *link_encoder = NULL;
 	struct stream_encoder *stream_encoder = pipe_ctx->stream_res.stream_enc;
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	struct hpo_dp_link_encoder *hpo_dp_link_encoder = link->hpo_dp_link_enc;
+	struct hpo_dp_stream_encoder *hpo_dp_stream_encoder = pipe_ctx->stream_res.hpo_dp_stream_enc;
+#endif
 	struct dp_mst_stream_allocation_table proposed_table = {0};
 	struct fixed31_32 avg_time_slots_per_mtp = dc_fixpt_from_int(0);
 	int i;
@@ -3504,9 +3730,25 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 	 */
 
 	/* slot X.Y */
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	switch (dp_get_link_encoding_format(&link->cur_link_settings)) {
+	case DP_8b_10b_ENCODING:
+		stream_encoder->funcs->set_throttled_vcp_size(
+			stream_encoder,
+			avg_time_slots_per_mtp);
+		break;
+	case DP_128b_132b_ENCODING:
+		hpo_dp_link_encoder->funcs->set_throttled_vcp_size(
+				hpo_dp_link_encoder,
+				hpo_dp_stream_encoder->inst,
+				avg_time_slots_per_mtp);
+		break;
+	}
+#else
 	stream_encoder->funcs->set_throttled_vcp_size(
 		stream_encoder,
 		avg_time_slots_per_mtp);
+#endif
 
 	/* TODO: which component is responsible for remove payload table? */
 	if (mst_mode) {
@@ -3516,8 +3758,16 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 				&proposed_table,
 				false)) {
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+			update_mst_stream_alloc_table(
+						link,
+						pipe_ctx->stream_res.stream_enc,
+						pipe_ctx->stream_res.hpo_dp_stream_enc,
+						&proposed_table);
+#else
 			update_mst_stream_alloc_table(
 				link, pipe_ctx->stream_res.stream_enc, &proposed_table);
+#endif
 		}
 		else {
 				DC_LOG_WARNING("Failed to update"
@@ -3533,6 +3783,20 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 			link->mst_stream_alloc_table.stream_count);
 
 	for (i = 0; i < MAX_CONTROLLER_NUM; i++) {
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		DC_LOG_MST("stream_enc[%d]: %p      "
+		"stream[%d].hpo_dp_stream_enc: %p      "
+		"stream[%d].vcp_id: %d      "
+		"stream[%d].slot_count: %d\n",
+		i,
+		(void *) link->mst_stream_alloc_table.stream_allocations[i].stream_enc,
+		i,
+		(void *) link->mst_stream_alloc_table.stream_allocations[i].hpo_dp_stream_enc,
+		i,
+		link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
+		i,
+		link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+#else
 		DC_LOG_MST("stream_enc[%d]: %p      "
 		"stream[%d].vcp_id: %d      "
 		"stream[%d].slot_count: %d\n",
@@ -3542,11 +3806,27 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 		link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
 		i,
 		link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+#endif
 	}
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	switch (dp_get_link_encoding_format(&link->cur_link_settings)) {
+	case DP_8b_10b_ENCODING:
+		link_encoder->funcs->update_mst_stream_allocation_table(
+			link_encoder,
+			&link->mst_stream_alloc_table);
+		break;
+	case DP_128b_132b_ENCODING:
+		hpo_dp_link_encoder->funcs->update_stream_allocation_table(
+				hpo_dp_link_encoder,
+				&link->mst_stream_alloc_table);
+		break;
+	}
+#else
 	link_encoder->funcs->update_mst_stream_allocation_table(
 		link_encoder,
 		&link->mst_stream_alloc_table);
+#endif
 
 	if (mst_mode) {
 		dm_helpers_dp_mst_poll_for_allocation_change_trigger(
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 296b0defcd1c..bb96e4e9ccfc 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
@@ -5993,6 +5993,25 @@ enum dp_link_encoding dp_get_link_encoding_format(const struct dc_link_settings
 }
 
 #if defined(CONFIG_DRM_AMD_DC_DCN)
+enum dp_link_encoding dc_link_dp_mst_decide_link_encoding_format(const struct dc_link *link)
+{
+	struct dc_link_settings link_settings = {0};
+
+	if (!dc_is_dp_signal(link->connector_signal))
+		return DP_UNKNOWN_ENCODING;
+
+	if (link->preferred_link_setting.lane_count !=
+			LANE_COUNT_UNKNOWN &&
+			link->preferred_link_setting.link_rate !=
+					LINK_RATE_UNKNOWN) {
+		link_settings = link->preferred_link_setting;
+	} else {
+		decide_mst_link_settings(link, &link_settings);
+	}
+
+	return dp_get_link_encoding_format(&link_settings);
+}
+
 // TODO - DP2.0 Link: Fix get_lane_status to handle LTTPR offset (SST and MST)
 static void get_lane_status(
 	struct dc_link *link,
diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h
index a73d64b1fd33..08815310d85b 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_link.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_link.h
@@ -295,6 +295,10 @@ enum dc_detect_reason {
 bool dc_link_detect(struct dc_link *dc_link, enum dc_detect_reason reason);
 bool dc_link_get_hpd_state(struct dc_link *dc_link);
 enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx);
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+enum dc_status dc_link_reduce_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t req_pbn);
+enum dc_status dc_link_increase_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t req_pbn);
+#endif
 
 /* Notify DC about DP RX Interrupt (aka Short Pulse Interrupt).
  * Return:
@@ -424,4 +428,7 @@ uint32_t dc_bandwidth_in_kbps_from_timing(
 bool dc_link_is_fec_supported(const struct dc_link *link);
 bool dc_link_should_enable_fec(const struct dc_link *link);
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+enum dp_link_encoding dc_link_dp_mst_decide_link_encoding_format(const struct dc_link *link);
+#endif
 #endif /* DC_LINK_H_ */
diff --git a/drivers/gpu/drm/amd/display/dc/dc_stream.h b/drivers/gpu/drm/amd/display/dc/dc_stream.h
index b8ebc1f09538..e37c4a10bfd5 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_stream.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_stream.h
@@ -115,6 +115,13 @@ struct periodic_interrupt_config {
 	int lines_offset;
 };
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+struct dc_mst_stream_bw_update {
+	bool is_increase; // is bandwidth reduced or increased
+	uint32_t mst_stream_bw; // new mst bandwidth in kbps
+};
+#endif
+
 union stream_update_flags {
 	struct {
 		uint32_t scaling:1;
@@ -125,6 +132,9 @@ union stream_update_flags {
 		uint32_t gamut_remap:1;
 		uint32_t wb_update:1;
 		uint32_t dsc_changed : 1;
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		uint32_t mst_bw : 1;
+#endif
 	} bits;
 
 	uint32_t raw;
@@ -278,6 +288,9 @@ struct dc_stream_update {
 
 	struct dc_writeback_update *wb_update;
 	struct dc_dsc_config *dsc_config;
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	struct dc_mst_stream_bw_update *mst_bw_update;
+#endif
 	struct dc_transfer_func *func_shaper;
 	struct dc_3dlut *lut3d_func;
 
-- 
2.25.1

[Intel-gfx] [PATCH 3/4] drm/amd/display: Add DP 2.0 MST DC Support

[Bhawanpreet Lakha]

From: Fangzhi Zuo <Jerry.Zuo@amd.com>

Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc.c      |  14 +
 drivers/gpu/drm/amd/display/dc/core/dc_link.c | 280 ++++++++++++++++++
 .../gpu/drm/amd/display/dc/core/dc_link_dp.c  |  19 ++
 drivers/gpu/drm/amd/display/dc/dc_link.h      |   7 +
 drivers/gpu/drm/amd/display/dc/dc_stream.h    |  13 +
 5 files changed, 333 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index 8be04be19124..935a50d6e933 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -2354,6 +2354,11 @@ static enum surface_update_type check_update_surfaces_for_stream(
 		if (stream_update->dsc_config)
 			su_flags->bits.dsc_changed = 1;
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		if (stream_update->mst_bw_update)
+			su_flags->bits.mst_bw = 1;
+#endif
+
 		if (su_flags->raw != 0)
 			overall_type = UPDATE_TYPE_FULL;
 
@@ -2731,6 +2736,15 @@ static void commit_planes_do_stream_update(struct dc *dc,
 			if (stream_update->dsc_config)
 				dp_update_dsc_config(pipe_ctx);
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+			if (stream_update->mst_bw_update) {
+				if (stream_update->mst_bw_update->is_increase)
+					dc_link_increase_mst_payload(pipe_ctx, stream_update->mst_bw_update->mst_stream_bw);
+				else
+					dc_link_reduce_mst_payload(pipe_ctx, stream_update->mst_bw_update->mst_stream_bw);
+			}
+#endif
+
 			if (stream_update->pending_test_pattern) {
 				dc_link_dp_set_test_pattern(stream->link,
 					stream->test_pattern.type,
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index e5d6cbd7ea78..b23972b6a27c 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -3232,6 +3232,9 @@ static struct fixed31_32 get_pbn_from_timing(struct pipe_ctx *pipe_ctx)
 static void update_mst_stream_alloc_table(
 	struct dc_link *link,
 	struct stream_encoder *stream_enc,
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	struct hpo_dp_stream_encoder *hpo_dp_stream_enc, // TODO: Rename stream_enc to dio_stream_enc?
+#endif
 	const struct dp_mst_stream_allocation_table *proposed_table)
 {
 	struct link_mst_stream_allocation work_table[MAX_CONTROLLER_NUM] = { 0 };
@@ -3267,6 +3270,9 @@ static void update_mst_stream_alloc_table(
 			work_table[i].slot_count =
 				proposed_table->stream_allocations[i].slot_count;
 			work_table[i].stream_enc = stream_enc;
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+			work_table[i].hpo_dp_stream_enc = hpo_dp_stream_enc;
+#endif
 		}
 	}
 
@@ -3389,6 +3395,10 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 	struct dc_link *link = stream->link;
 	struct link_encoder *link_encoder = NULL;
 	struct stream_encoder *stream_encoder = pipe_ctx->stream_res.stream_enc;
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	struct hpo_dp_link_encoder *hpo_dp_link_encoder = link->hpo_dp_link_enc;
+	struct hpo_dp_stream_encoder *hpo_dp_stream_encoder = pipe_ctx->stream_res.hpo_dp_stream_enc;
+#endif
 	struct dp_mst_stream_allocation_table proposed_table = {0};
 	struct fixed31_32 avg_time_slots_per_mtp;
 	struct fixed31_32 pbn;
@@ -3416,7 +3426,14 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 		&proposed_table,
 		true)) {
 		update_mst_stream_alloc_table(
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+					link,
+					pipe_ctx->stream_res.stream_enc,
+					pipe_ctx->stream_res.hpo_dp_stream_enc,
+					&proposed_table);
+#else
 					link, pipe_ctx->stream_res.stream_enc, &proposed_table);
+#endif
 	}
 	else
 		DC_LOG_WARNING("Failed to update"
@@ -3430,6 +3447,20 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 			link->mst_stream_alloc_table.stream_count);
 
 	for (i = 0; i < MAX_CONTROLLER_NUM; i++) {
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		DC_LOG_MST("stream_enc[%d]: %p      "
+		"stream[%d].hpo_dp_stream_enc: %p      "
+		"stream[%d].vcp_id: %d      "
+		"stream[%d].slot_count: %d\n",
+		i,
+		(void *) link->mst_stream_alloc_table.stream_allocations[i].stream_enc,
+		i,
+		(void *) link->mst_stream_alloc_table.stream_allocations[i].hpo_dp_stream_enc,
+		i,
+		link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
+		i,
+		link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+#else
 		DC_LOG_MST("stream_enc[%d]: %p      "
 		"stream[%d].vcp_id: %d      "
 		"stream[%d].slot_count: %d\n",
@@ -3439,14 +3470,30 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 		link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
 		i,
 		link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+#endif
 	}
 
 	ASSERT(proposed_table.stream_count > 0);
 
 	/* program DP source TX for payload */
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	switch (dp_get_link_encoding_format(&link->cur_link_settings)) {
+	case DP_8b_10b_ENCODING:
+		link_encoder->funcs->update_mst_stream_allocation_table(
+			link_encoder,
+			&link->mst_stream_alloc_table);
+		break;
+	case DP_128b_132b_ENCODING:
+		hpo_dp_link_encoder->funcs->update_stream_allocation_table(
+				hpo_dp_link_encoder,
+				&link->mst_stream_alloc_table);
+		break;
+	}
+#else
 	link_encoder->funcs->update_mst_stream_allocation_table(
 		link_encoder,
 		&link->mst_stream_alloc_table);
+#endif
 
 	/* send down message */
 	ret = dm_helpers_dp_mst_poll_for_allocation_change_trigger(
@@ -3469,13 +3516,188 @@ enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 	pbn = get_pbn_from_timing(pipe_ctx);
 	avg_time_slots_per_mtp = dc_fixpt_div(pbn, pbn_per_slot);
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	switch (dp_get_link_encoding_format(&link->cur_link_settings)) {
+	case DP_8b_10b_ENCODING:
+		stream_encoder->funcs->set_throttled_vcp_size(
+			stream_encoder,
+			avg_time_slots_per_mtp);
+		break;
+	case DP_128b_132b_ENCODING:
+		hpo_dp_link_encoder->funcs->set_throttled_vcp_size(
+				hpo_dp_link_encoder,
+				hpo_dp_stream_encoder->inst,
+				avg_time_slots_per_mtp);
+		break;
+	}
+#else
 	stream_encoder->funcs->set_throttled_vcp_size(
 		stream_encoder,
 		avg_time_slots_per_mtp);
+#endif
+
+	return DC_OK;
+
+}
+
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+enum dc_status dc_link_reduce_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t bw_in_kbps)
+{
+	struct dc_stream_state *stream = pipe_ctx->stream;
+	struct dc_link *link = stream->link;
+	struct fixed31_32 avg_time_slots_per_mtp;
+	struct fixed31_32 pbn;
+	struct fixed31_32 pbn_per_slot;
+	struct link_encoder *link_encoder = link->link_enc;
+	struct stream_encoder *stream_encoder = pipe_ctx->stream_res.stream_enc;
+	struct dp_mst_stream_allocation_table proposed_table = {0};
+	uint8_t i;
+	enum act_return_status ret;
+	DC_LOGGER_INIT(link->ctx->logger);
+
+	/* decrease throttled vcp size */
+	pbn_per_slot = get_pbn_per_slot(stream);
+	pbn = get_pbn_from_bw_in_kbps(bw_in_kbps);
+	avg_time_slots_per_mtp = dc_fixpt_div(pbn, pbn_per_slot);
+
+	stream_encoder->funcs->set_throttled_vcp_size(
+				stream_encoder,
+				avg_time_slots_per_mtp);
+
+	/* send ALLOCATE_PAYLOAD sideband message with updated pbn */
+	dm_helpers_dp_mst_send_payload_allocation(
+			stream->ctx,
+			stream,
+			true);
+
+	/* notify immediate branch device table update */
+	if (dm_helpers_dp_mst_write_payload_allocation_table(
+			stream->ctx,
+			stream,
+			&proposed_table,
+			true)) {
+		/* update mst stream allocation table software state */
+		update_mst_stream_alloc_table(
+				link,
+				pipe_ctx->stream_res.stream_enc,
+				pipe_ctx->stream_res.hpo_dp_stream_enc,
+				&proposed_table);
+	} else {
+		DC_LOG_WARNING("Failed to update"
+				"MST allocation table for"
+				"pipe idx:%d\n",
+				pipe_ctx->pipe_idx);
+	}
+
+	DC_LOG_MST("%s  "
+			"stream_count: %d: \n ",
+			__func__,
+			link->mst_stream_alloc_table.stream_count);
+
+	for (i = 0; i < MAX_CONTROLLER_NUM; i++) {
+		DC_LOG_MST("stream_enc[%d]: %p      "
+				"stream[%d].vcp_id: %d      "
+				"stream[%d].slot_count: %d\n",
+				i,
+				(void *) link->mst_stream_alloc_table.stream_allocations[i].stream_enc,
+				i,
+				link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
+				i,
+				link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+	}
+
+	ASSERT(proposed_table.stream_count > 0);
+
+	/* update mst stream allocation table hardware state */
+	link_encoder->funcs->update_mst_stream_allocation_table(
+			link_encoder,
+			&link->mst_stream_alloc_table);
+
+	/* poll for immediate branch device ACT handled */
+	ret = dm_helpers_dp_mst_poll_for_allocation_change_trigger(
+			stream->ctx,
+			stream);
 
 	return DC_OK;
+}
+
+enum dc_status dc_link_increase_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t bw_in_kbps)
+{
+	struct dc_stream_state *stream = pipe_ctx->stream;
+	struct dc_link *link = stream->link;
+	struct fixed31_32 avg_time_slots_per_mtp;
+	struct fixed31_32 pbn;
+	struct fixed31_32 pbn_per_slot;
+	struct link_encoder *link_encoder = link->link_enc;
+	struct stream_encoder *stream_encoder = pipe_ctx->stream_res.stream_enc;
+	struct dp_mst_stream_allocation_table proposed_table = {0};
+	uint8_t i;
+	enum act_return_status ret;
+	DC_LOGGER_INIT(link->ctx->logger);
+
+	/* notify immediate branch device table update */
+	if (dm_helpers_dp_mst_write_payload_allocation_table(
+				stream->ctx,
+				stream,
+				&proposed_table,
+				true)) {
+		/* update mst stream allocation table software state */
+		update_mst_stream_alloc_table(
+				link,
+				pipe_ctx->stream_res.stream_enc,
+				pipe_ctx->stream_res.hpo_dp_stream_enc,
+				&proposed_table);
+	}
+
+	DC_LOG_MST("%s  "
+			"stream_count: %d: \n ",
+			__func__,
+			link->mst_stream_alloc_table.stream_count);
+
+	for (i = 0; i < MAX_CONTROLLER_NUM; i++) {
+		DC_LOG_MST("stream_enc[%d]: %p      "
+				"stream[%d].vcp_id: %d      "
+				"stream[%d].slot_count: %d\n",
+				i,
+				(void *) link->mst_stream_alloc_table.stream_allocations[i].stream_enc,
+				i,
+				link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
+				i,
+				link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+	}
+
+	ASSERT(proposed_table.stream_count > 0);
+
+	/* update mst stream allocation table hardware state */
+	link_encoder->funcs->update_mst_stream_allocation_table(
+			link_encoder,
+			&link->mst_stream_alloc_table);
+
+	/* poll for immediate branch device ACT handled */
+	ret = dm_helpers_dp_mst_poll_for_allocation_change_trigger(
+			stream->ctx,
+			stream);
+
+	if (ret != ACT_LINK_LOST) {
+		/* send ALLOCATE_PAYLOAD sideband message with updated pbn */
+		dm_helpers_dp_mst_send_payload_allocation(
+				stream->ctx,
+				stream,
+				true);
+	}
+
+	/* increase throttled vcp size */
+	pbn = get_pbn_from_bw_in_kbps(bw_in_kbps);
+	pbn_per_slot = get_pbn_per_slot(stream);
+	avg_time_slots_per_mtp = dc_fixpt_div(pbn, pbn_per_slot);
+
+	stream_encoder->funcs->set_throttled_vcp_size(
+				stream_encoder,
+				avg_time_slots_per_mtp);
 
+	return DC_OK;
 }
+#endif
 
 static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 {
@@ -3483,6 +3705,10 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 	struct dc_link *link = stream->link;
 	struct link_encoder *link_encoder = NULL;
 	struct stream_encoder *stream_encoder = pipe_ctx->stream_res.stream_enc;
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	struct hpo_dp_link_encoder *hpo_dp_link_encoder = link->hpo_dp_link_enc;
+	struct hpo_dp_stream_encoder *hpo_dp_stream_encoder = pipe_ctx->stream_res.hpo_dp_stream_enc;
+#endif
 	struct dp_mst_stream_allocation_table proposed_table = {0};
 	struct fixed31_32 avg_time_slots_per_mtp = dc_fixpt_from_int(0);
 	int i;
@@ -3504,9 +3730,25 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 	 */
 
 	/* slot X.Y */
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	switch (dp_get_link_encoding_format(&link->cur_link_settings)) {
+	case DP_8b_10b_ENCODING:
+		stream_encoder->funcs->set_throttled_vcp_size(
+			stream_encoder,
+			avg_time_slots_per_mtp);
+		break;
+	case DP_128b_132b_ENCODING:
+		hpo_dp_link_encoder->funcs->set_throttled_vcp_size(
+				hpo_dp_link_encoder,
+				hpo_dp_stream_encoder->inst,
+				avg_time_slots_per_mtp);
+		break;
+	}
+#else
 	stream_encoder->funcs->set_throttled_vcp_size(
 		stream_encoder,
 		avg_time_slots_per_mtp);
+#endif
 
 	/* TODO: which component is responsible for remove payload table? */
 	if (mst_mode) {
@@ -3516,8 +3758,16 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 				&proposed_table,
 				false)) {
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+			update_mst_stream_alloc_table(
+						link,
+						pipe_ctx->stream_res.stream_enc,
+						pipe_ctx->stream_res.hpo_dp_stream_enc,
+						&proposed_table);
+#else
 			update_mst_stream_alloc_table(
 				link, pipe_ctx->stream_res.stream_enc, &proposed_table);
+#endif
 		}
 		else {
 				DC_LOG_WARNING("Failed to update"
@@ -3533,6 +3783,20 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 			link->mst_stream_alloc_table.stream_count);
 
 	for (i = 0; i < MAX_CONTROLLER_NUM; i++) {
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		DC_LOG_MST("stream_enc[%d]: %p      "
+		"stream[%d].hpo_dp_stream_enc: %p      "
+		"stream[%d].vcp_id: %d      "
+		"stream[%d].slot_count: %d\n",
+		i,
+		(void *) link->mst_stream_alloc_table.stream_allocations[i].stream_enc,
+		i,
+		(void *) link->mst_stream_alloc_table.stream_allocations[i].hpo_dp_stream_enc,
+		i,
+		link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
+		i,
+		link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+#else
 		DC_LOG_MST("stream_enc[%d]: %p      "
 		"stream[%d].vcp_id: %d      "
 		"stream[%d].slot_count: %d\n",
@@ -3542,11 +3806,27 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 		link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
 		i,
 		link->mst_stream_alloc_table.stream_allocations[i].slot_count);
+#endif
 	}
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	switch (dp_get_link_encoding_format(&link->cur_link_settings)) {
+	case DP_8b_10b_ENCODING:
+		link_encoder->funcs->update_mst_stream_allocation_table(
+			link_encoder,
+			&link->mst_stream_alloc_table);
+		break;
+	case DP_128b_132b_ENCODING:
+		hpo_dp_link_encoder->funcs->update_stream_allocation_table(
+				hpo_dp_link_encoder,
+				&link->mst_stream_alloc_table);
+		break;
+	}
+#else
 	link_encoder->funcs->update_mst_stream_allocation_table(
 		link_encoder,
 		&link->mst_stream_alloc_table);
+#endif
 
 	if (mst_mode) {
 		dm_helpers_dp_mst_poll_for_allocation_change_trigger(
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 296b0defcd1c..bb96e4e9ccfc 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
@@ -5993,6 +5993,25 @@ enum dp_link_encoding dp_get_link_encoding_format(const struct dc_link_settings
 }
 
 #if defined(CONFIG_DRM_AMD_DC_DCN)
+enum dp_link_encoding dc_link_dp_mst_decide_link_encoding_format(const struct dc_link *link)
+{
+	struct dc_link_settings link_settings = {0};
+
+	if (!dc_is_dp_signal(link->connector_signal))
+		return DP_UNKNOWN_ENCODING;
+
+	if (link->preferred_link_setting.lane_count !=
+			LANE_COUNT_UNKNOWN &&
+			link->preferred_link_setting.link_rate !=
+					LINK_RATE_UNKNOWN) {
+		link_settings = link->preferred_link_setting;
+	} else {
+		decide_mst_link_settings(link, &link_settings);
+	}
+
+	return dp_get_link_encoding_format(&link_settings);
+}
+
 // TODO - DP2.0 Link: Fix get_lane_status to handle LTTPR offset (SST and MST)
 static void get_lane_status(
 	struct dc_link *link,
diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h
index a73d64b1fd33..08815310d85b 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_link.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_link.h
@@ -295,6 +295,10 @@ enum dc_detect_reason {
 bool dc_link_detect(struct dc_link *dc_link, enum dc_detect_reason reason);
 bool dc_link_get_hpd_state(struct dc_link *dc_link);
 enum dc_status dc_link_allocate_mst_payload(struct pipe_ctx *pipe_ctx);
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+enum dc_status dc_link_reduce_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t req_pbn);
+enum dc_status dc_link_increase_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t req_pbn);
+#endif
 
 /* Notify DC about DP RX Interrupt (aka Short Pulse Interrupt).
  * Return:
@@ -424,4 +428,7 @@ uint32_t dc_bandwidth_in_kbps_from_timing(
 bool dc_link_is_fec_supported(const struct dc_link *link);
 bool dc_link_should_enable_fec(const struct dc_link *link);
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+enum dp_link_encoding dc_link_dp_mst_decide_link_encoding_format(const struct dc_link *link);
+#endif
 #endif /* DC_LINK_H_ */
diff --git a/drivers/gpu/drm/amd/display/dc/dc_stream.h b/drivers/gpu/drm/amd/display/dc/dc_stream.h
index b8ebc1f09538..e37c4a10bfd5 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_stream.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_stream.h
@@ -115,6 +115,13 @@ struct periodic_interrupt_config {
 	int lines_offset;
 };
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+struct dc_mst_stream_bw_update {
+	bool is_increase; // is bandwidth reduced or increased
+	uint32_t mst_stream_bw; // new mst bandwidth in kbps
+};
+#endif
+
 union stream_update_flags {
 	struct {
 		uint32_t scaling:1;
@@ -125,6 +132,9 @@ union stream_update_flags {
 		uint32_t gamut_remap:1;
 		uint32_t wb_update:1;
 		uint32_t dsc_changed : 1;
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		uint32_t mst_bw : 1;
+#endif
 	} bits;
 
 	uint32_t raw;
@@ -278,6 +288,9 @@ struct dc_stream_update {
 
 	struct dc_writeback_update *wb_update;
 	struct dc_dsc_config *dsc_config;
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	struct dc_mst_stream_bw_update *mst_bw_update;
+#endif
 	struct dc_transfer_func *func_shaper;
 	struct dc_3dlut *lut3d_func;
 
-- 
2.25.1

[PATCH 4/4] drm/amd/display: Add DP 2.0 MST DM Support

[Bhawanpreet Lakha]

[Why]
Add DP2 MST and debugfs support

[How]
Update the slot info based on the link encoding format

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 29 +++++++++++++++++++
 .../amd/display/amdgpu_dm/amdgpu_dm_debugfs.c |  3 ++
 .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  5 +++-
 3 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index e56f73e299ef..875425ee91d0 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -10741,6 +10741,8 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 #if defined(CONFIG_DRM_AMD_DC_DCN)
 	struct dsc_mst_fairness_vars vars[MAX_PIPES];
 #endif
+	struct drm_dp_mst_topology_state *mst_state;
+	struct drm_dp_mst_topology_mgr *mgr;
 
 	trace_amdgpu_dm_atomic_check_begin(state);
 
@@ -10948,6 +10950,33 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 		lock_and_validation_needed = true;
 	}
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	/* set the slot info for each mst_state based on the link encoding format */
+	for_each_new_mst_mgr_in_state(state, mgr, mst_state, i) {
+		struct amdgpu_dm_connector *aconnector;
+		struct drm_connector *connector;
+		struct drm_connector_list_iter iter;
+		u8 link_coding_cap;
+
+		if (!mgr->mst_state )
+			continue;
+
+		drm_connector_list_iter_begin(dev, &iter);
+		drm_for_each_connector_iter(connector, &iter) {
+			int id = connector->index;
+
+			if (id == mst_state->mgr->conn_base_id) {
+				aconnector = to_amdgpu_dm_connector(connector);
+				link_coding_cap = dc_link_dp_mst_decide_link_encoding_format(aconnector->dc_link);
+				drm_dp_mst_update_slots(mst_state, link_coding_cap);
+
+				break;
+			}
+		}
+		drm_connector_list_iter_end(&iter);
+
+	}
+#endif
 	/**
 	 * Streams and planes are reset when there are changes that affect
 	 * bandwidth. Anything that affects bandwidth needs to go through
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
index 9b3ad56607bb..1a68a674913c 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
@@ -294,6 +294,9 @@ static ssize_t dp_link_settings_write(struct file *f, const char __user *buf,
 	case LINK_RATE_RBR2:
 	case LINK_RATE_HIGH2:
 	case LINK_RATE_HIGH3:
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	case LINK_RATE_UHBR10:
+#endif
 		break;
 	default:
 		valid_input = false;
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index 6169488e2011..53b5cc7b0679 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -219,6 +219,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 	struct drm_dp_mst_topology_mgr *mst_mgr;
 	struct drm_dp_mst_port *mst_port;
 	bool ret;
+	u8 link_coding_cap;
 
 	aconnector = (struct amdgpu_dm_connector *)stream->dm_stream_context;
 	/* Accessing the connector state is required for vcpi_slots allocation
@@ -238,6 +239,8 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 
 	mst_port = aconnector->port;
 
+	link_coding_cap = dc_link_dp_mst_decide_link_encoding_format(aconnector->dc_link);
+
 	if (enable) {
 
 		ret = drm_dp_mst_allocate_vcpi(mst_mgr, mst_port,
@@ -251,7 +254,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 	}
 
 	/* It's OK for this to fail */
-	drm_dp_update_payload_part1(mst_mgr, 1);
+	drm_dp_update_payload_part1(mst_mgr, (link_coding_cap == DP_CAP_ANSI_128B132B) ? 0:1);
 
 	/* mst_mgr->->payloads are VC payload notify MST branch using DPCD or
 	 * AUX message. The sequence is slot 1-63 allocated sequence for each
-- 
2.25.1

[Intel-gfx] [PATCH 4/4] drm/amd/display: Add DP 2.0 MST DM Support

[Bhawanpreet Lakha]

[Why]
Add DP2 MST and debugfs support

[How]
Update the slot info based on the link encoding format

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 29 +++++++++++++++++++
 .../amd/display/amdgpu_dm/amdgpu_dm_debugfs.c |  3 ++
 .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  5 +++-
 3 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index e56f73e299ef..875425ee91d0 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -10741,6 +10741,8 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 #if defined(CONFIG_DRM_AMD_DC_DCN)
 	struct dsc_mst_fairness_vars vars[MAX_PIPES];
 #endif
+	struct drm_dp_mst_topology_state *mst_state;
+	struct drm_dp_mst_topology_mgr *mgr;
 
 	trace_amdgpu_dm_atomic_check_begin(state);
 
@@ -10948,6 +10950,33 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 		lock_and_validation_needed = true;
 	}
 
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	/* set the slot info for each mst_state based on the link encoding format */
+	for_each_new_mst_mgr_in_state(state, mgr, mst_state, i) {
+		struct amdgpu_dm_connector *aconnector;
+		struct drm_connector *connector;
+		struct drm_connector_list_iter iter;
+		u8 link_coding_cap;
+
+		if (!mgr->mst_state )
+			continue;
+
+		drm_connector_list_iter_begin(dev, &iter);
+		drm_for_each_connector_iter(connector, &iter) {
+			int id = connector->index;
+
+			if (id == mst_state->mgr->conn_base_id) {
+				aconnector = to_amdgpu_dm_connector(connector);
+				link_coding_cap = dc_link_dp_mst_decide_link_encoding_format(aconnector->dc_link);
+				drm_dp_mst_update_slots(mst_state, link_coding_cap);
+
+				break;
+			}
+		}
+		drm_connector_list_iter_end(&iter);
+
+	}
+#endif
 	/**
 	 * Streams and planes are reset when there are changes that affect
 	 * bandwidth. Anything that affects bandwidth needs to go through
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
index 9b3ad56607bb..1a68a674913c 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
@@ -294,6 +294,9 @@ static ssize_t dp_link_settings_write(struct file *f, const char __user *buf,
 	case LINK_RATE_RBR2:
 	case LINK_RATE_HIGH2:
 	case LINK_RATE_HIGH3:
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+	case LINK_RATE_UHBR10:
+#endif
 		break;
 	default:
 		valid_input = false;
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index 6169488e2011..53b5cc7b0679 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -219,6 +219,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 	struct drm_dp_mst_topology_mgr *mst_mgr;
 	struct drm_dp_mst_port *mst_port;
 	bool ret;
+	u8 link_coding_cap;
 
 	aconnector = (struct amdgpu_dm_connector *)stream->dm_stream_context;
 	/* Accessing the connector state is required for vcpi_slots allocation
@@ -238,6 +239,8 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 
 	mst_port = aconnector->port;
 
+	link_coding_cap = dc_link_dp_mst_decide_link_encoding_format(aconnector->dc_link);
+
 	if (enable) {
 
 		ret = drm_dp_mst_allocate_vcpi(mst_mgr, mst_port,
@@ -251,7 +254,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 	}
 
 	/* It's OK for this to fail */
-	drm_dp_update_payload_part1(mst_mgr, 1);
+	drm_dp_update_payload_part1(mst_mgr, (link_coding_cap == DP_CAP_ANSI_128B132B) ? 0:1);
 
 	/* mst_mgr->->payloads are VC payload notify MST branch using DPCD or
 	 * AUX message. The sequence is slot 1-63 allocated sequence for each
-- 
2.25.1

[Intel-gfx] ✗ Fi.CI.BUILD: failure for series starting with [1/4] drm: Remove slot checks in dp mst topology during commit

[Patchwork]

== Series Details ==

Series: series starting with [1/4] drm: Remove slot checks in dp mst topology during commit
URL   : https://patchwork.freedesktop.org/series/96060/
State : failure

== Summary ==

Applying: drm: Remove slot checks in dp mst topology during commit
Applying: drm: Update MST First Link Slot Information Based on Encoding Format
Applying: drm/amd/display: Add DP 2.0 MST DC Support
error: sha1 information is lacking or useless (drivers/gpu/drm/amd/display/dc/core/dc.c).
error: could not build fake ancestor
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0003 drm/amd/display: Add DP 2.0 MST DC Support
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

Re: [Intel-gfx] [PATCH 1/4] drm: Remove slot checks in dp mst topology during commit

[Lyude Paul]

Reviewed-by: Lyude Paul <lyude@redhat.com>

On Wed, 2021-10-20 at 10:16 -0400, Bhawanpreet Lakha wrote:
> This code path is used during commit, and we dont expect things to fail
> during the commit stage, so remove this.
> 
> Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
> ---
>  drivers/gpu/drm/drm_dp_mst_topology.c | 6 +-----
>  1 file changed, 1 insertion(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c
> b/drivers/gpu/drm/drm_dp_mst_topology.c
> index ad0795afc21c..5ab3b3a46e89 100644
> --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> @@ -4332,10 +4332,6 @@ static int drm_dp_init_vcpi(struct
> drm_dp_mst_topology_mgr *mgr,
>  {
>         int ret;
>  
> -       /* max. time slots - one slot for MTP header */
> -       if (slots > 63)
> -               return -ENOSPC;
> -
>         vcpi->pbn = pbn;
>         vcpi->aligned_pbn = slots * mgr->pbn_div;
>         vcpi->num_slots = slots;
> @@ -4538,7 +4534,7 @@ bool drm_dp_mst_allocate_vcpi(struct
> drm_dp_mst_topology_mgr *mgr,
>  
>         ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn, slots);
>         if (ret) {
> -               drm_dbg_kms(mgr->dev, "failed to init vcpi slots=%d max=63
> ret=%d\n",
> +               drm_dbg_kms(mgr->dev, "failed to init vcpi slots=%d
> ret=%d\n",
>                             DIV_ROUND_UP(pbn, mgr->pbn_div), ret);
>                 drm_dp_mst_topology_put_port(port);
>                 goto out;

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat

Re: [PATCH 1/4] drm: Remove slot checks in dp mst topology during commit

[Lyude Paul]

Reviewed-by: Lyude Paul <lyude@redhat.com>

On Wed, 2021-10-20 at 10:16 -0400, Bhawanpreet Lakha wrote:
> This code path is used during commit, and we dont expect things to fail
> during the commit stage, so remove this.
> 
> Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
> ---
>  drivers/gpu/drm/drm_dp_mst_topology.c | 6 +-----
>  1 file changed, 1 insertion(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c
> b/drivers/gpu/drm/drm_dp_mst_topology.c
> index ad0795afc21c..5ab3b3a46e89 100644
> --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> @@ -4332,10 +4332,6 @@ static int drm_dp_init_vcpi(struct
> drm_dp_mst_topology_mgr *mgr,
>  {
>         int ret;
>  
> -       /* max. time slots - one slot for MTP header */
> -       if (slots > 63)
> -               return -ENOSPC;
> -
>         vcpi->pbn = pbn;
>         vcpi->aligned_pbn = slots * mgr->pbn_div;
>         vcpi->num_slots = slots;
> @@ -4538,7 +4534,7 @@ bool drm_dp_mst_allocate_vcpi(struct
> drm_dp_mst_topology_mgr *mgr,
>  
>         ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn, slots);
>         if (ret) {
> -               drm_dbg_kms(mgr->dev, "failed to init vcpi slots=%d max=63
> ret=%d\n",
> +               drm_dbg_kms(mgr->dev, "failed to init vcpi slots=%d
> ret=%d\n",
>                             DIV_ROUND_UP(pbn, mgr->pbn_div), ret);
>                 drm_dp_mst_topology_put_port(port);
>                 goto out;

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat

Re: [PATCH 2/4] drm: Update MST First Link Slot Information Based on Encoding Format

[Lyude Paul]

Awesome! So this all looks fine to me, just some formatting changes:

On Wed, 2021-10-20 at 10:16 -0400, Bhawanpreet Lakha wrote:
> 8b/10b encoding format requires to reserve the first slot for
> recording metadata. Real data transmission starts from the second slot,
> with a total of available 63 slots available.
> 
> In 128b/132b encoding format, metadata is transmitted separately
> in LLCP packet before MTP. Real data transmission starts from
> the first slot, with a total of 64 slots available.
> 
> v2:
> * Move total/start slots to mst_state, and copy it to mst_mgr in
> atomic_check
> 
> v3:
> * Only keep the slot info on the mst_state
> * add a start_slot parameter to the payload function, to facilitate non
>   atomic drivers (this is a temporary workaround and should be removed when
>   we are moving out the non atomic driver helpers)
> 
> Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
> Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
> ---
>  .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  2 +-
>  drivers/gpu/drm/drm_dp_mst_topology.c         | 34 ++++++++++++++++---
>  drivers/gpu/drm/i915/display/intel_dp_mst.c   |  4 +--
>  drivers/gpu/drm/nouveau/dispnv50/disp.c       |  2 +-
>  drivers/gpu/drm/radeon/radeon_dp_mst.c        |  4 +--
>  include/drm/drm_dp_mst_helper.h               |  5 ++-
>  6 files changed, 40 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> index ff0f91c93ba4..6169488e2011 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> @@ -251,7 +251,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
>         }
>  
>         /* It's OK for this to fail */
> -       drm_dp_update_payload_part1(mst_mgr);
> +       drm_dp_update_payload_part1(mst_mgr, 1);
>  
>         /* mst_mgr->->payloads are VC payload notify MST branch using DPCD
> or
>          * AUX message. The sequence is slot 1-63 allocated sequence for
> each
> diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c
> b/drivers/gpu/drm/drm_dp_mst_topology.c
> index 5ab3b3a46e89..d188a5269070 100644
> --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> @@ -3353,6 +3353,9 @@ static int drm_dp_destroy_payload_step2(struct
> drm_dp_mst_topology_mgr *mgr,
>  /**
>   * drm_dp_update_payload_part1() - Execute payload update part 1
>   * @mgr: manager to use.
> + * @start_slot: this is the cur slot
> + *  NOTE: start_slot is a temporary workaround for non-atomic drivers,
> + *  this will be removed when non-atomic mst helpers are moved out of the
> helper

We should probably add a space right before NOTE, and reformat these comments
since there's a bit of an indent at the start (unfortunately, I don't think
kdoc is smart enough to retain the indent in the documentation it generates).

>   *
>   * This iterates over all proposed virtual channels, and tries to
>   * allocate space in the link for them. For 0->slots transitions,
> @@ -3363,12 +3366,12 @@ static int drm_dp_destroy_payload_step2(struct
> drm_dp_mst_topology_mgr *mgr,
>   * after calling this the driver should generate ACT and payload
>   * packets.
>   */
> -int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
> +int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int
> start_slot)
>  {
>         struct drm_dp_payload req_payload;
>         struct drm_dp_mst_port *port;
>         int i, j;
> -       int cur_slots = 1;
> +       int cur_slots = start_slot;
>         bool skip;
>  
>         mutex_lock(&mgr->payload_lock);
> @@ -4503,6 +4506,26 @@ int drm_dp_atomic_release_vcpi_slots(struct
> drm_atomic_state *state,
>  }
>  EXPORT_SYMBOL(drm_dp_atomic_release_vcpi_slots);
>  
> +/**
> + * drm_dp_mst_update_slots() - updates the slot info depending on the DP
> ecoding format
> + * @mst_state: mst_state to update
> + * @link_ecoding_cap: the ecoding format on the link
> + */
> +void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state,
> uint8_t link_ecoding_cap)
> +{
> +       if (link_ecoding_cap == DP_CAP_ANSI_128B132B) {
> +               mst_state->total_avail_slots = 64;
> +               mst_state->start_slot = 0;
> +       } else {
> +               mst_state->total_avail_slots = 63;
> +               mst_state->start_slot = 1;
> +       }
> +
> +       DRM_DEBUG_KMS("%s ecoding format on mst_state 0x%p\n",
> +                       (link_ecoding_cap == DP_CAP_ANSI_128B132B) ?
> "128b/132b":"8b/10b", mst_state->mgr);
> +}
> +EXPORT_SYMBOL(drm_dp_mst_update_slots);

Some typos (s/ecoding/encoding), and also this should be reformatted to a 100
character column limit.

Other then that, nice work! After making the formatting changes I mentioned
here, you can consider this:

Reviewed-by: Lyude Paul <lyude@redhat.com>

Since this patch series touches multiple drivers, we may want to merge this
through drm-misc-next (or maybe just through the normal AMD repos, whatever
other driver maintainers think is the easiest). I imagine I'll probably be the
one pushing it in the drm-misc-next case, so I'll go and poke some folks to
see how we want to move forward. As well, you'll probably want to find someone
from AMD to help you out with reviewing the last two patches in this series (I
assume this shouldn't be too difficult though since you work there :).

> +
>  /**
>   * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
>   * @mgr: manager for this port
> @@ -5222,7 +5245,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct
> drm_dp_mst_topology_mgr *mgr,
>                                          struct drm_dp_mst_topology_state
> *mst_state)
>  {
>         struct drm_dp_vcpi_allocation *vcpi;
> -       int avail_slots = 63, payload_count = 0;
> +       int avail_slots = mst_state->total_avail_slots, payload_count = 0;
>  
>         list_for_each_entry(vcpi, &mst_state->vcpis, next) {
>                 /* Releasing VCPI is always OK-even if the port is gone */
> @@ -5251,7 +5274,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct
> drm_dp_mst_topology_mgr *mgr,
>                 }
>         }
>         drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p VCPI avail=%d
> used=%d\n",
> -                      mgr, mst_state, avail_slots, 63 - avail_slots);
> +                      mgr, mst_state, avail_slots, mst_state-
> >total_avail_slots - avail_slots);
>  
>         return 0;
>  }
> @@ -5528,6 +5551,9 @@ int drm_dp_mst_topology_mgr_init(struct
> drm_dp_mst_topology_mgr *mgr,
>         if (mst_state == NULL)
>                 return -ENOMEM;
>  
> +       mst_state->total_avail_slots = 63;
> +       mst_state->start_slot = 1;
> +
>         mst_state->mgr = mgr;
>         INIT_LIST_HEAD(&mst_state->vcpis);
>  
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index b170e272bdee..d3a24189a12c 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -368,7 +368,7 @@ static void intel_mst_disable_dp(struct
> intel_atomic_state *state,
>  
>         drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, connector->port);
>  
> -       ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
> +       ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
>         if (ret) {
>                 drm_dbg_kms(&i915->drm, "failed to update payload %d\n",
> ret);
>         }
> @@ -516,7 +516,7 @@ static void intel_mst_pre_enable_dp(struct
> intel_atomic_state *state,
>  
>         intel_dp->active_mst_links++;
>  
> -       ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
> +       ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
>  
>         /*
>          * Before Gen 12 this is not done as part of
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> index f949767698fc..6c8c59c26dbf 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> @@ -1413,7 +1413,7 @@ nv50_mstm_prepare(struct nv50_mstm *mstm)
>         int ret;
>  
>         NV_ATOMIC(drm, "%s: mstm prepare\n", mstm->outp->base.base.name);
> -       ret = drm_dp_update_payload_part1(&mstm->mgr);
> +       ret = drm_dp_update_payload_part1(&mstm->mgr, 1);
>  
>         drm_for_each_encoder(encoder, mstm->outp->base.base.dev) {
>                 if (encoder->encoder_type == DRM_MODE_ENCODER_DPMST) {
> diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c
> b/drivers/gpu/drm/radeon/radeon_dp_mst.c
> index ec867fa880a4..751c2c075e09 100644
> --- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
> +++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
> @@ -423,7 +423,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int
> mode)
>                 drm_dp_mst_allocate_vcpi(&radeon_connector->mst_port-
> >mst_mgr,
>                                          radeon_connector->port,
>                                          mst_enc->pbn, slots);
> -               drm_dp_update_payload_part1(&radeon_connector->mst_port-
> >mst_mgr);
> +               drm_dp_update_payload_part1(&radeon_connector->mst_port-
> >mst_mgr, 1);
>  
>                 radeon_dp_mst_set_be_cntl(primary, mst_enc,
>                                           radeon_connector->mst_port-
> >hpd.hpd, true);
> @@ -452,7 +452,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int
> mode)
>                         return;
>  
>                 drm_dp_mst_reset_vcpi_slots(&radeon_connector->mst_port-
> >mst_mgr, mst_enc->port);
> -               drm_dp_update_payload_part1(&radeon_connector->mst_port-
> >mst_mgr);
> +               drm_dp_update_payload_part1(&radeon_connector->mst_port-
> >mst_mgr, 1);
>  
>                 drm_dp_check_act_status(&radeon_connector->mst_port-
> >mst_mgr);
>                 /* and this can also fail */
> diff --git a/include/drm/drm_dp_mst_helper.h
> b/include/drm/drm_dp_mst_helper.h
> index ddb9231d0309..3207b49586fc 100644
> --- a/include/drm/drm_dp_mst_helper.h
> +++ b/include/drm/drm_dp_mst_helper.h
> @@ -554,6 +554,8 @@ struct drm_dp_mst_topology_state {
>         struct drm_private_state base;
>         struct list_head vcpis;
>         struct drm_dp_mst_topology_mgr *mgr;
> +       u8 total_avail_slots;
> +       u8 start_slot;
>  };
>  
>  #define to_dp_mst_topology_mgr(x) container_of(x, struct
> drm_dp_mst_topology_mgr, base)
> @@ -806,6 +808,7 @@ int drm_dp_mst_get_vcpi_slots(struct
> drm_dp_mst_topology_mgr *mgr, struct drm_dp
>  
>  void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
> struct drm_dp_mst_port *port);
>  
> +void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state,
> uint8_t link_ecoding_cap);
>  
>  void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
>                                 struct drm_dp_mst_port *port);
> @@ -815,7 +818,7 @@ int drm_dp_find_vcpi_slots(struct
> drm_dp_mst_topology_mgr *mgr,
>                            int pbn);
>  
>  
> -int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
> +int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int
> start_slot);
>  
>  
>  int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat

Re: [Intel-gfx] [PATCH 2/4] drm: Update MST First Link Slot Information Based on Encoding Format

[Lyude Paul]

Awesome! So this all looks fine to me, just some formatting changes:

On Wed, 2021-10-20 at 10:16 -0400, Bhawanpreet Lakha wrote:
> 8b/10b encoding format requires to reserve the first slot for
> recording metadata. Real data transmission starts from the second slot,
> with a total of available 63 slots available.
> 
> In 128b/132b encoding format, metadata is transmitted separately
> in LLCP packet before MTP. Real data transmission starts from
> the first slot, with a total of 64 slots available.
> 
> v2:
> * Move total/start slots to mst_state, and copy it to mst_mgr in
> atomic_check
> 
> v3:
> * Only keep the slot info on the mst_state
> * add a start_slot parameter to the payload function, to facilitate non
>   atomic drivers (this is a temporary workaround and should be removed when
>   we are moving out the non atomic driver helpers)
> 
> Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
> Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
> ---
>  .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  2 +-
>  drivers/gpu/drm/drm_dp_mst_topology.c         | 34 ++++++++++++++++---
>  drivers/gpu/drm/i915/display/intel_dp_mst.c   |  4 +--
>  drivers/gpu/drm/nouveau/dispnv50/disp.c       |  2 +-
>  drivers/gpu/drm/radeon/radeon_dp_mst.c        |  4 +--
>  include/drm/drm_dp_mst_helper.h               |  5 ++-
>  6 files changed, 40 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> index ff0f91c93ba4..6169488e2011 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> @@ -251,7 +251,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
>         }
>  
>         /* It's OK for this to fail */
> -       drm_dp_update_payload_part1(mst_mgr);
> +       drm_dp_update_payload_part1(mst_mgr, 1);
>  
>         /* mst_mgr->->payloads are VC payload notify MST branch using DPCD
> or
>          * AUX message. The sequence is slot 1-63 allocated sequence for
> each
> diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c
> b/drivers/gpu/drm/drm_dp_mst_topology.c
> index 5ab3b3a46e89..d188a5269070 100644
> --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> @@ -3353,6 +3353,9 @@ static int drm_dp_destroy_payload_step2(struct
> drm_dp_mst_topology_mgr *mgr,
>  /**
>   * drm_dp_update_payload_part1() - Execute payload update part 1
>   * @mgr: manager to use.
> + * @start_slot: this is the cur slot
> + *  NOTE: start_slot is a temporary workaround for non-atomic drivers,
> + *  this will be removed when non-atomic mst helpers are moved out of the
> helper

We should probably add a space right before NOTE, and reformat these comments
since there's a bit of an indent at the start (unfortunately, I don't think
kdoc is smart enough to retain the indent in the documentation it generates).

>   *
>   * This iterates over all proposed virtual channels, and tries to
>   * allocate space in the link for them. For 0->slots transitions,
> @@ -3363,12 +3366,12 @@ static int drm_dp_destroy_payload_step2(struct
> drm_dp_mst_topology_mgr *mgr,
>   * after calling this the driver should generate ACT and payload
>   * packets.
>   */
> -int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
> +int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int
> start_slot)
>  {
>         struct drm_dp_payload req_payload;
>         struct drm_dp_mst_port *port;
>         int i, j;
> -       int cur_slots = 1;
> +       int cur_slots = start_slot;
>         bool skip;
>  
>         mutex_lock(&mgr->payload_lock);
> @@ -4503,6 +4506,26 @@ int drm_dp_atomic_release_vcpi_slots(struct
> drm_atomic_state *state,
>  }
>  EXPORT_SYMBOL(drm_dp_atomic_release_vcpi_slots);
>  
> +/**
> + * drm_dp_mst_update_slots() - updates the slot info depending on the DP
> ecoding format
> + * @mst_state: mst_state to update
> + * @link_ecoding_cap: the ecoding format on the link
> + */
> +void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state,
> uint8_t link_ecoding_cap)
> +{
> +       if (link_ecoding_cap == DP_CAP_ANSI_128B132B) {
> +               mst_state->total_avail_slots = 64;
> +               mst_state->start_slot = 0;
> +       } else {
> +               mst_state->total_avail_slots = 63;
> +               mst_state->start_slot = 1;
> +       }
> +
> +       DRM_DEBUG_KMS("%s ecoding format on mst_state 0x%p\n",
> +                       (link_ecoding_cap == DP_CAP_ANSI_128B132B) ?
> "128b/132b":"8b/10b", mst_state->mgr);
> +}
> +EXPORT_SYMBOL(drm_dp_mst_update_slots);

Some typos (s/ecoding/encoding), and also this should be reformatted to a 100
character column limit.

Other then that, nice work! After making the formatting changes I mentioned
here, you can consider this:

Reviewed-by: Lyude Paul <lyude@redhat.com>

Since this patch series touches multiple drivers, we may want to merge this
through drm-misc-next (or maybe just through the normal AMD repos, whatever
other driver maintainers think is the easiest). I imagine I'll probably be the
one pushing it in the drm-misc-next case, so I'll go and poke some folks to
see how we want to move forward. As well, you'll probably want to find someone
from AMD to help you out with reviewing the last two patches in this series (I
assume this shouldn't be too difficult though since you work there :).

> +
>  /**
>   * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
>   * @mgr: manager for this port
> @@ -5222,7 +5245,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct
> drm_dp_mst_topology_mgr *mgr,
>                                          struct drm_dp_mst_topology_state
> *mst_state)
>  {
>         struct drm_dp_vcpi_allocation *vcpi;
> -       int avail_slots = 63, payload_count = 0;
> +       int avail_slots = mst_state->total_avail_slots, payload_count = 0;
>  
>         list_for_each_entry(vcpi, &mst_state->vcpis, next) {
>                 /* Releasing VCPI is always OK-even if the port is gone */
> @@ -5251,7 +5274,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct
> drm_dp_mst_topology_mgr *mgr,
>                 }
>         }
>         drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p VCPI avail=%d
> used=%d\n",
> -                      mgr, mst_state, avail_slots, 63 - avail_slots);
> +                      mgr, mst_state, avail_slots, mst_state-
> >total_avail_slots - avail_slots);
>  
>         return 0;
>  }
> @@ -5528,6 +5551,9 @@ int drm_dp_mst_topology_mgr_init(struct
> drm_dp_mst_topology_mgr *mgr,
>         if (mst_state == NULL)
>                 return -ENOMEM;
>  
> +       mst_state->total_avail_slots = 63;
> +       mst_state->start_slot = 1;
> +
>         mst_state->mgr = mgr;
>         INIT_LIST_HEAD(&mst_state->vcpis);
>  
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index b170e272bdee..d3a24189a12c 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -368,7 +368,7 @@ static void intel_mst_disable_dp(struct
> intel_atomic_state *state,
>  
>         drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, connector->port);
>  
> -       ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
> +       ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
>         if (ret) {
>                 drm_dbg_kms(&i915->drm, "failed to update payload %d\n",
> ret);
>         }
> @@ -516,7 +516,7 @@ static void intel_mst_pre_enable_dp(struct
> intel_atomic_state *state,
>  
>         intel_dp->active_mst_links++;
>  
> -       ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
> +       ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
>  
>         /*
>          * Before Gen 12 this is not done as part of
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> index f949767698fc..6c8c59c26dbf 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> @@ -1413,7 +1413,7 @@ nv50_mstm_prepare(struct nv50_mstm *mstm)
>         int ret;
>  
>         NV_ATOMIC(drm, "%s: mstm prepare\n", mstm->outp->base.base.name);
> -       ret = drm_dp_update_payload_part1(&mstm->mgr);
> +       ret = drm_dp_update_payload_part1(&mstm->mgr, 1);
>  
>         drm_for_each_encoder(encoder, mstm->outp->base.base.dev) {
>                 if (encoder->encoder_type == DRM_MODE_ENCODER_DPMST) {
> diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c
> b/drivers/gpu/drm/radeon/radeon_dp_mst.c
> index ec867fa880a4..751c2c075e09 100644
> --- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
> +++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
> @@ -423,7 +423,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int
> mode)
>                 drm_dp_mst_allocate_vcpi(&radeon_connector->mst_port-
> >mst_mgr,
>                                          radeon_connector->port,
>                                          mst_enc->pbn, slots);
> -               drm_dp_update_payload_part1(&radeon_connector->mst_port-
> >mst_mgr);
> +               drm_dp_update_payload_part1(&radeon_connector->mst_port-
> >mst_mgr, 1);
>  
>                 radeon_dp_mst_set_be_cntl(primary, mst_enc,
>                                           radeon_connector->mst_port-
> >hpd.hpd, true);
> @@ -452,7 +452,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int
> mode)
>                         return;
>  
>                 drm_dp_mst_reset_vcpi_slots(&radeon_connector->mst_port-
> >mst_mgr, mst_enc->port);
> -               drm_dp_update_payload_part1(&radeon_connector->mst_port-
> >mst_mgr);
> +               drm_dp_update_payload_part1(&radeon_connector->mst_port-
> >mst_mgr, 1);
>  
>                 drm_dp_check_act_status(&radeon_connector->mst_port-
> >mst_mgr);
>                 /* and this can also fail */
> diff --git a/include/drm/drm_dp_mst_helper.h
> b/include/drm/drm_dp_mst_helper.h
> index ddb9231d0309..3207b49586fc 100644
> --- a/include/drm/drm_dp_mst_helper.h
> +++ b/include/drm/drm_dp_mst_helper.h
> @@ -554,6 +554,8 @@ struct drm_dp_mst_topology_state {
>         struct drm_private_state base;
>         struct list_head vcpis;
>         struct drm_dp_mst_topology_mgr *mgr;
> +       u8 total_avail_slots;
> +       u8 start_slot;
>  };
>  
>  #define to_dp_mst_topology_mgr(x) container_of(x, struct
> drm_dp_mst_topology_mgr, base)
> @@ -806,6 +808,7 @@ int drm_dp_mst_get_vcpi_slots(struct
> drm_dp_mst_topology_mgr *mgr, struct drm_dp
>  
>  void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
> struct drm_dp_mst_port *port);
>  
> +void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state,
> uint8_t link_ecoding_cap);
>  
>  void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
>                                 struct drm_dp_mst_port *port);
> @@ -815,7 +818,7 @@ int drm_dp_find_vcpi_slots(struct
> drm_dp_mst_topology_mgr *mgr,
>                            int pbn);
>  
>  
> -int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
> +int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int
> start_slot);
>  
>  
>  int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat

[PATCH 2/4] drm: Update MST First Link Slot Information Based on Encoding Format

[Bhawanpreet Lakha]

8b/10b encoding format requires to reserve the first slot for
recording metadata. Real data transmission starts from the second slot,
with a total of available 63 slots available.

In 128b/132b encoding format, metadata is transmitted separately
in LLCP packet before MTP. Real data transmission starts from
the first slot, with a total of 64 slots available.

v2:
* Move total/start slots to mst_state, and copy it to mst_mgr in
atomic_check

v3:
* Only keep the slot info on the mst_state
* add a start_slot parameter to the payload function, to facilitate non
  atomic drivers (this is a temporary workaround and should be removed when
  we are moving out the non atomic driver helpers)

v4:
*fixed typo and formatting

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
---
 .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  2 +-
 drivers/gpu/drm/drm_dp_mst_topology.c         | 36 ++++++++++++++++---
 drivers/gpu/drm/i915/display/intel_dp_mst.c   |  4 +--
 drivers/gpu/drm/nouveau/dispnv50/disp.c       |  2 +-
 drivers/gpu/drm/radeon/radeon_dp_mst.c        |  4 +--
 include/drm/drm_dp_mst_helper.h               |  5 ++-
 6 files changed, 42 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index ff0f91c93ba4..6169488e2011 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -251,7 +251,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 	}
 
 	/* It's OK for this to fail */
-	drm_dp_update_payload_part1(mst_mgr);
+	drm_dp_update_payload_part1(mst_mgr, 1);
 
 	/* mst_mgr->->payloads are VC payload notify MST branch using DPCD or
 	 * AUX message. The sequence is slot 1-63 allocated sequence for each
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 5ab3b3a46e89..857c5d15e81d 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -3353,6 +3353,10 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
 /**
  * drm_dp_update_payload_part1() - Execute payload update part 1
  * @mgr: manager to use.
+ * @start_slot: this is the cur slot
+ *
+ * NOTE: start_slot is a temporary workaround for non-atomic drivers,
+ * this will be removed when non-atomic mst helpers are moved out of the helper
  *
  * This iterates over all proposed virtual channels, and tries to
  * allocate space in the link for them. For 0->slots transitions,
@@ -3363,12 +3367,12 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
  * after calling this the driver should generate ACT and payload
  * packets.
  */
-int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot)
 {
 	struct drm_dp_payload req_payload;
 	struct drm_dp_mst_port *port;
 	int i, j;
-	int cur_slots = 1;
+	int cur_slots = start_slot;
 	bool skip;
 
 	mutex_lock(&mgr->payload_lock);
@@ -4503,6 +4507,27 @@ int drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
 }
 EXPORT_SYMBOL(drm_dp_atomic_release_vcpi_slots);
 
+/**
+ * drm_dp_mst_update_slots() - updates the slot info depending on the DP ecoding format
+ * @mst_state: mst_state to update
+ * @link_encoding_cap: the ecoding format on the link
+ */
+void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_encoding_cap)
+{
+	if (link_encoding_cap == DP_CAP_ANSI_128B132B) {
+		mst_state->total_avail_slots = 64;
+		mst_state->start_slot = 0;
+	} else {
+		mst_state->total_avail_slots = 63;
+		mst_state->start_slot = 1;
+	}
+
+	DRM_DEBUG_KMS("%s encoding format on mst_state 0x%p\n",
+			(link_encoding_cap == DP_CAP_ANSI_128B132B) ? "128b/132b":"8b/10b",
+			mst_state->mgr);
+}
+EXPORT_SYMBOL(drm_dp_mst_update_slots);
+
 /**
  * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
  * @mgr: manager for this port
@@ -5222,7 +5247,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
 					 struct drm_dp_mst_topology_state *mst_state)
 {
 	struct drm_dp_vcpi_allocation *vcpi;
-	int avail_slots = 63, payload_count = 0;
+	int avail_slots = mst_state->total_avail_slots, payload_count = 0;
 
 	list_for_each_entry(vcpi, &mst_state->vcpis, next) {
 		/* Releasing VCPI is always OK-even if the port is gone */
@@ -5251,7 +5276,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
 		}
 	}
 	drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p VCPI avail=%d used=%d\n",
-		       mgr, mst_state, avail_slots, 63 - avail_slots);
+		       mgr, mst_state, avail_slots, mst_state->total_avail_slots - avail_slots);
 
 	return 0;
 }
@@ -5528,6 +5553,9 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
 	if (mst_state == NULL)
 		return -ENOMEM;
 
+	mst_state->total_avail_slots = 63;
+	mst_state->start_slot = 1;
+
 	mst_state->mgr = mgr;
 	INIT_LIST_HEAD(&mst_state->vcpis);
 
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index b170e272bdee..d3a24189a12c 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -368,7 +368,7 @@ static void intel_mst_disable_dp(struct intel_atomic_state *state,
 
 	drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, connector->port);
 
-	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
+	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
 	if (ret) {
 		drm_dbg_kms(&i915->drm, "failed to update payload %d\n", ret);
 	}
@@ -516,7 +516,7 @@ static void intel_mst_pre_enable_dp(struct intel_atomic_state *state,
 
 	intel_dp->active_mst_links++;
 
-	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
+	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
 
 	/*
 	 * Before Gen 12 this is not done as part of
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index f949767698fc..6c8c59c26dbf 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -1413,7 +1413,7 @@ nv50_mstm_prepare(struct nv50_mstm *mstm)
 	int ret;
 
 	NV_ATOMIC(drm, "%s: mstm prepare\n", mstm->outp->base.base.name);
-	ret = drm_dp_update_payload_part1(&mstm->mgr);
+	ret = drm_dp_update_payload_part1(&mstm->mgr, 1);
 
 	drm_for_each_encoder(encoder, mstm->outp->base.base.dev) {
 		if (encoder->encoder_type == DRM_MODE_ENCODER_DPMST) {
diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c
index ec867fa880a4..751c2c075e09 100644
--- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
+++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
@@ -423,7 +423,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
 		drm_dp_mst_allocate_vcpi(&radeon_connector->mst_port->mst_mgr,
 					 radeon_connector->port,
 					 mst_enc->pbn, slots);
-		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
+		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
 
 		radeon_dp_mst_set_be_cntl(primary, mst_enc,
 					  radeon_connector->mst_port->hpd.hpd, true);
@@ -452,7 +452,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
 			return;
 
 		drm_dp_mst_reset_vcpi_slots(&radeon_connector->mst_port->mst_mgr, mst_enc->port);
-		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
+		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
 
 		drm_dp_check_act_status(&radeon_connector->mst_port->mst_mgr);
 		/* and this can also fail */
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index ddb9231d0309..78044ac5b59b 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -554,6 +554,8 @@ struct drm_dp_mst_topology_state {
 	struct drm_private_state base;
 	struct list_head vcpis;
 	struct drm_dp_mst_topology_mgr *mgr;
+	u8 total_avail_slots;
+	u8 start_slot;
 };
 
 #define to_dp_mst_topology_mgr(x) container_of(x, struct drm_dp_mst_topology_mgr, base)
@@ -806,6 +808,7 @@ int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp
 
 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
 
+void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_encoding_cap);
 
 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 				struct drm_dp_mst_port *port);
@@ -815,7 +818,7 @@ int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
 			   int pbn);
 
 
-int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot);
 
 
 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);
-- 
2.25.1

[PATCH 2/4] drm: Update MST First Link Slot Information Based on Encoding Format

[Bhawanpreet Lakha]

8b/10b encoding format requires to reserve the first slot for
recording metadata. Real data transmission starts from the second slot,
with a total of available 63 slots available.

In 128b/132b encoding format, metadata is transmitted separately
in LLCP packet before MTP. Real data transmission starts from
the first slot, with a total of 64 slots available.

v2:
* Move total/start slots to mst_state, and copy it to mst_mgr in
atomic_check

v3:
* Only keep the slot info on the mst_state
* add a start_slot parameter to the payload function, to facilitate non
  atomic drivers (this is a temporary workaround and should be removed when
  we are moving out the non atomic driver helpers)

v4:
*fixed typo and formatting

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
---
 .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  2 +-
 drivers/gpu/drm/drm_dp_mst_topology.c         | 38 ++++++++++++++++---
 drivers/gpu/drm/i915/display/intel_dp_mst.c   |  4 +-
 drivers/gpu/drm/nouveau/dispnv50/disp.c       |  2 +-
 drivers/gpu/drm/radeon/radeon_dp_mst.c        |  4 +-
 include/drm/drm_dp_mst_helper.h               |  5 ++-
 6 files changed, 43 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index ff0f91c93ba4..6169488e2011 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -251,7 +251,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 	}
 
 	/* It's OK for this to fail */
-	drm_dp_update_payload_part1(mst_mgr);
+	drm_dp_update_payload_part1(mst_mgr, 1);
 
 	/* mst_mgr->->payloads are VC payload notify MST branch using DPCD or
 	 * AUX message. The sequence is slot 1-63 allocated sequence for each
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 5ab3b3a46e89..82ee6791576c 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -3353,6 +3353,10 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
 /**
  * drm_dp_update_payload_part1() - Execute payload update part 1
  * @mgr: manager to use.
+ * @start_slot: this is the cur slot
+ *
+ * NOTE: start_slot is a temporary workaround for non-atomic drivers,
+ * this will be removed when non-atomic mst helpers are moved out of the helper
  *
  * This iterates over all proposed virtual channels, and tries to
  * allocate space in the link for them. For 0->slots transitions,
@@ -3360,15 +3364,15 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
  * transitions, this writes the updated VCPIs and removes the
  * remote VC payloads.
  *
- * after calling this the driver should generate ACT and payload
+ *after calling this the driver should generate ACT and payload
  * packets.
  */
-int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot)
 {
 	struct drm_dp_payload req_payload;
 	struct drm_dp_mst_port *port;
 	int i, j;
-	int cur_slots = 1;
+	int cur_slots = start_slot;
 	bool skip;
 
 	mutex_lock(&mgr->payload_lock);
@@ -4503,6 +4507,27 @@ int drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
 }
 EXPORT_SYMBOL(drm_dp_atomic_release_vcpi_slots);
 
+/**
+ * drm_dp_mst_update_slots() - updates the slot info depending on the DP ecoding format
+ * @mst_state: mst_state to update
+ * @link_encoding_cap: the ecoding format on the link
+ */
+void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_encoding_cap)
+{
+	if (link_encoding_cap == DP_CAP_ANSI_128B132B) {
+		mst_state->total_avail_slots = 64;
+		mst_state->start_slot = 0;
+	} else {
+		mst_state->total_avail_slots = 63;
+		mst_state->start_slot = 1;
+	}
+
+	DRM_DEBUG_KMS("%s encoding format on mst_state 0x%p\n",
+			(link_encoding_cap == DP_CAP_ANSI_128B132B) ? "128b/132b":"8b/10b",
+			mst_state->mgr);
+}
+EXPORT_SYMBOL(drm_dp_mst_update_slots);
+
 /**
  * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
  * @mgr: manager for this port
@@ -5222,7 +5247,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
 					 struct drm_dp_mst_topology_state *mst_state)
 {
 	struct drm_dp_vcpi_allocation *vcpi;
-	int avail_slots = 63, payload_count = 0;
+	int avail_slots = mst_state->total_avail_slots, payload_count = 0;
 
 	list_for_each_entry(vcpi, &mst_state->vcpis, next) {
 		/* Releasing VCPI is always OK-even if the port is gone */
@@ -5251,7 +5276,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
 		}
 	}
 	drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p VCPI avail=%d used=%d\n",
-		       mgr, mst_state, avail_slots, 63 - avail_slots);
+		       mgr, mst_state, avail_slots, mst_state->total_avail_slots - avail_slots);
 
 	return 0;
 }
@@ -5528,6 +5553,9 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
 	if (mst_state == NULL)
 		return -ENOMEM;
 
+	mst_state->total_avail_slots = 63;
+	mst_state->start_slot = 1;
+
 	mst_state->mgr = mgr;
 	INIT_LIST_HEAD(&mst_state->vcpis);
 
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index b170e272bdee..d3a24189a12c 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -368,7 +368,7 @@ static void intel_mst_disable_dp(struct intel_atomic_state *state,
 
 	drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, connector->port);
 
-	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
+	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
 	if (ret) {
 		drm_dbg_kms(&i915->drm, "failed to update payload %d\n", ret);
 	}
@@ -516,7 +516,7 @@ static void intel_mst_pre_enable_dp(struct intel_atomic_state *state,
 
 	intel_dp->active_mst_links++;
 
-	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
+	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
 
 	/*
 	 * Before Gen 12 this is not done as part of
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index f949767698fc..6c8c59c26dbf 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -1413,7 +1413,7 @@ nv50_mstm_prepare(struct nv50_mstm *mstm)
 	int ret;
 
 	NV_ATOMIC(drm, "%s: mstm prepare\n", mstm->outp->base.base.name);
-	ret = drm_dp_update_payload_part1(&mstm->mgr);
+	ret = drm_dp_update_payload_part1(&mstm->mgr, 1);
 
 	drm_for_each_encoder(encoder, mstm->outp->base.base.dev) {
 		if (encoder->encoder_type == DRM_MODE_ENCODER_DPMST) {
diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c
index ec867fa880a4..751c2c075e09 100644
--- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
+++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
@@ -423,7 +423,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
 		drm_dp_mst_allocate_vcpi(&radeon_connector->mst_port->mst_mgr,
 					 radeon_connector->port,
 					 mst_enc->pbn, slots);
-		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
+		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
 
 		radeon_dp_mst_set_be_cntl(primary, mst_enc,
 					  radeon_connector->mst_port->hpd.hpd, true);
@@ -452,7 +452,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
 			return;
 
 		drm_dp_mst_reset_vcpi_slots(&radeon_connector->mst_port->mst_mgr, mst_enc->port);
-		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
+		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
 
 		drm_dp_check_act_status(&radeon_connector->mst_port->mst_mgr);
 		/* and this can also fail */
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index ddb9231d0309..78044ac5b59b 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -554,6 +554,8 @@ struct drm_dp_mst_topology_state {
 	struct drm_private_state base;
 	struct list_head vcpis;
 	struct drm_dp_mst_topology_mgr *mgr;
+	u8 total_avail_slots;
+	u8 start_slot;
 };
 
 #define to_dp_mst_topology_mgr(x) container_of(x, struct drm_dp_mst_topology_mgr, base)
@@ -806,6 +808,7 @@ int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp
 
 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
 
+void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_encoding_cap);
 
 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 				struct drm_dp_mst_port *port);
@@ -815,7 +818,7 @@ int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
 			   int pbn);
 
 
-int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot);
 
 
 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);
-- 
2.25.1

Re: [PATCH 2/4] drm: Update MST First Link Slot Information Based on Encoding Format

[Jani Nikula]

On Tue, 19 Oct 2021, Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com> wrote:
> 8b/10b encoding format requires to reserve the first slot for
> recording metadata. Real data transmission starts from the second slot,
> with a total of available 63 slots available.
>
> In 128b/132b encoding format, metadata is transmitted separately
> in LLCP packet before MTP. Real data transmission starts from
> the first slot, with a total of 64 slots available.

Please send the patches as a fresh series instead of replying to the old
thread, it's getting too confusing. Also, please Cc: intel-gfx mailing
list, so you'll get our CI results on it. (Although I'm not sure how
many machines we have with MST setups, but it's better than nothing.)

BR,
Jani.


>
> v2:
> * Move total/start slots to mst_state, and copy it to mst_mgr in
> atomic_check
>
> v3:
> * Only keep the slot info on the mst_state
> * add a start_slot parameter to the payload function, to facilitate non
>   atomic drivers (this is a temporary workaround and should be removed when
>   we are moving out the non atomic driver helpers)
>
> Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
> Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
> ---
>  .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  2 +-
>  drivers/gpu/drm/drm_dp_mst_topology.c         | 34 ++++++++++++++++---
>  drivers/gpu/drm/i915/display/intel_dp_mst.c   |  4 +--
>  drivers/gpu/drm/nouveau/dispnv50/disp.c       |  2 +-
>  drivers/gpu/drm/radeon/radeon_dp_mst.c        |  4 +--
>  include/drm/drm_dp_mst_helper.h               |  5 ++-
>  6 files changed, 40 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> index ff0f91c93ba4..6169488e2011 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
> @@ -251,7 +251,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
>  	}
>  
>  	/* It's OK for this to fail */
> -	drm_dp_update_payload_part1(mst_mgr);
> +	drm_dp_update_payload_part1(mst_mgr, 1);
>  
>  	/* mst_mgr->->payloads are VC payload notify MST branch using DPCD or
>  	 * AUX message. The sequence is slot 1-63 allocated sequence for each
> diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
> index 5ab3b3a46e89..d188a5269070 100644
> --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> @@ -3353,6 +3353,9 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
>  /**
>   * drm_dp_update_payload_part1() - Execute payload update part 1
>   * @mgr: manager to use.
> + * @start_slot: this is the cur slot
> + *  NOTE: start_slot is a temporary workaround for non-atomic drivers,
> + *  this will be removed when non-atomic mst helpers are moved out of the helper
>   *
>   * This iterates over all proposed virtual channels, and tries to
>   * allocate space in the link for them. For 0->slots transitions,
> @@ -3363,12 +3366,12 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
>   * after calling this the driver should generate ACT and payload
>   * packets.
>   */
> -int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
> +int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot)
>  {
>  	struct drm_dp_payload req_payload;
>  	struct drm_dp_mst_port *port;
>  	int i, j;
> -	int cur_slots = 1;
> +	int cur_slots = start_slot;
>  	bool skip;
>  
>  	mutex_lock(&mgr->payload_lock);
> @@ -4503,6 +4506,26 @@ int drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
>  }
>  EXPORT_SYMBOL(drm_dp_atomic_release_vcpi_slots);
>  
> +/**
> + * drm_dp_mst_update_slots() - updates the slot info depending on the DP ecoding format
> + * @mst_state: mst_state to update
> + * @link_ecoding_cap: the ecoding format on the link
> + */
> +void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_ecoding_cap)
> +{
> +	if (link_ecoding_cap == DP_CAP_ANSI_128B132B) {
> +		mst_state->total_avail_slots = 64;
> +		mst_state->start_slot = 0;
> +	} else {
> +		mst_state->total_avail_slots = 63;
> +		mst_state->start_slot = 1;
> +	}
> +
> +	DRM_DEBUG_KMS("%s ecoding format on mst_state 0x%p\n",
> +			(link_ecoding_cap == DP_CAP_ANSI_128B132B) ? "128b/132b":"8b/10b", mst_state->mgr);
> +}
> +EXPORT_SYMBOL(drm_dp_mst_update_slots);
> +
>  /**
>   * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
>   * @mgr: manager for this port
> @@ -5222,7 +5245,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
>  					 struct drm_dp_mst_topology_state *mst_state)
>  {
>  	struct drm_dp_vcpi_allocation *vcpi;
> -	int avail_slots = 63, payload_count = 0;
> +	int avail_slots = mst_state->total_avail_slots, payload_count = 0;
>  
>  	list_for_each_entry(vcpi, &mst_state->vcpis, next) {
>  		/* Releasing VCPI is always OK-even if the port is gone */
> @@ -5251,7 +5274,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
>  		}
>  	}
>  	drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p VCPI avail=%d used=%d\n",
> -		       mgr, mst_state, avail_slots, 63 - avail_slots);
> +		       mgr, mst_state, avail_slots, mst_state->total_avail_slots - avail_slots);
>  
>  	return 0;
>  }
> @@ -5528,6 +5551,9 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
>  	if (mst_state == NULL)
>  		return -ENOMEM;
>  
> +	mst_state->total_avail_slots = 63;
> +	mst_state->start_slot = 1;
> +
>  	mst_state->mgr = mgr;
>  	INIT_LIST_HEAD(&mst_state->vcpis);
>  
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index b170e272bdee..d3a24189a12c 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -368,7 +368,7 @@ static void intel_mst_disable_dp(struct intel_atomic_state *state,
>  
>  	drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, connector->port);
>  
> -	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
> +	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
>  	if (ret) {
>  		drm_dbg_kms(&i915->drm, "failed to update payload %d\n", ret);
>  	}
> @@ -516,7 +516,7 @@ static void intel_mst_pre_enable_dp(struct intel_atomic_state *state,
>  
>  	intel_dp->active_mst_links++;
>  
> -	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
> +	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
>  
>  	/*
>  	 * Before Gen 12 this is not done as part of
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> index f949767698fc..6c8c59c26dbf 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> @@ -1413,7 +1413,7 @@ nv50_mstm_prepare(struct nv50_mstm *mstm)
>  	int ret;
>  
>  	NV_ATOMIC(drm, "%s: mstm prepare\n", mstm->outp->base.base.name);
> -	ret = drm_dp_update_payload_part1(&mstm->mgr);
> +	ret = drm_dp_update_payload_part1(&mstm->mgr, 1);
>  
>  	drm_for_each_encoder(encoder, mstm->outp->base.base.dev) {
>  		if (encoder->encoder_type == DRM_MODE_ENCODER_DPMST) {
> diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c
> index ec867fa880a4..751c2c075e09 100644
> --- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
> +++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
> @@ -423,7 +423,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
>  		drm_dp_mst_allocate_vcpi(&radeon_connector->mst_port->mst_mgr,
>  					 radeon_connector->port,
>  					 mst_enc->pbn, slots);
> -		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
> +		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
>  
>  		radeon_dp_mst_set_be_cntl(primary, mst_enc,
>  					  radeon_connector->mst_port->hpd.hpd, true);
> @@ -452,7 +452,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
>  			return;
>  
>  		drm_dp_mst_reset_vcpi_slots(&radeon_connector->mst_port->mst_mgr, mst_enc->port);
> -		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
> +		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
>  
>  		drm_dp_check_act_status(&radeon_connector->mst_port->mst_mgr);
>  		/* and this can also fail */
> diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
> index ddb9231d0309..3207b49586fc 100644
> --- a/include/drm/drm_dp_mst_helper.h
> +++ b/include/drm/drm_dp_mst_helper.h
> @@ -554,6 +554,8 @@ struct drm_dp_mst_topology_state {
>  	struct drm_private_state base;
>  	struct list_head vcpis;
>  	struct drm_dp_mst_topology_mgr *mgr;
> +	u8 total_avail_slots;
> +	u8 start_slot;
>  };
>  
>  #define to_dp_mst_topology_mgr(x) container_of(x, struct drm_dp_mst_topology_mgr, base)
> @@ -806,6 +808,7 @@ int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp
>  
>  void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
>  
> +void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_ecoding_cap);
>  
>  void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
>  				struct drm_dp_mst_port *port);
> @@ -815,7 +818,7 @@ int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
>  			   int pbn);
>  
>  
> -int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
> +int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot);
>  
>  
>  int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);

-- 
Jani Nikula, Intel Open Source Graphics Center

[PATCH 2/4] drm: Update MST First Link Slot Information Based on Encoding Format

[Bhawanpreet Lakha]

8b/10b encoding format requires to reserve the first slot for
recording metadata. Real data transmission starts from the second slot,
with a total of available 63 slots available.

In 128b/132b encoding format, metadata is transmitted separately
in LLCP packet before MTP. Real data transmission starts from
the first slot, with a total of 64 slots available.

v2:
* Move total/start slots to mst_state, and copy it to mst_mgr in
atomic_check

v3:
* Only keep the slot info on the mst_state
* add a start_slot parameter to the payload function, to facilitate non
  atomic drivers (this is a temporary workaround and should be removed when
  we are moving out the non atomic driver helpers)

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
---
 .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  2 +-
 drivers/gpu/drm/drm_dp_mst_topology.c         | 34 ++++++++++++++++---
 drivers/gpu/drm/i915/display/intel_dp_mst.c   |  4 +--
 drivers/gpu/drm/nouveau/dispnv50/disp.c       |  2 +-
 drivers/gpu/drm/radeon/radeon_dp_mst.c        |  4 +--
 include/drm/drm_dp_mst_helper.h               |  5 ++-
 6 files changed, 40 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index ff0f91c93ba4..6169488e2011 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -251,7 +251,7 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 	}
 
 	/* It's OK for this to fail */
-	drm_dp_update_payload_part1(mst_mgr);
+	drm_dp_update_payload_part1(mst_mgr, 1);
 
 	/* mst_mgr->->payloads are VC payload notify MST branch using DPCD or
 	 * AUX message. The sequence is slot 1-63 allocated sequence for each
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 5ab3b3a46e89..d188a5269070 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -3353,6 +3353,9 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
 /**
  * drm_dp_update_payload_part1() - Execute payload update part 1
  * @mgr: manager to use.
+ * @start_slot: this is the cur slot
+ *  NOTE: start_slot is a temporary workaround for non-atomic drivers,
+ *  this will be removed when non-atomic mst helpers are moved out of the helper
  *
  * This iterates over all proposed virtual channels, and tries to
  * allocate space in the link for them. For 0->slots transitions,
@@ -3363,12 +3366,12 @@ static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
  * after calling this the driver should generate ACT and payload
  * packets.
  */
-int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot)
 {
 	struct drm_dp_payload req_payload;
 	struct drm_dp_mst_port *port;
 	int i, j;
-	int cur_slots = 1;
+	int cur_slots = start_slot;
 	bool skip;
 
 	mutex_lock(&mgr->payload_lock);
@@ -4503,6 +4506,26 @@ int drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
 }
 EXPORT_SYMBOL(drm_dp_atomic_release_vcpi_slots);
 
+/**
+ * drm_dp_mst_update_slots() - updates the slot info depending on the DP ecoding format
+ * @mst_state: mst_state to update
+ * @link_ecoding_cap: the ecoding format on the link
+ */
+void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_ecoding_cap)
+{
+	if (link_ecoding_cap == DP_CAP_ANSI_128B132B) {
+		mst_state->total_avail_slots = 64;
+		mst_state->start_slot = 0;
+	} else {
+		mst_state->total_avail_slots = 63;
+		mst_state->start_slot = 1;
+	}
+
+	DRM_DEBUG_KMS("%s ecoding format on mst_state 0x%p\n",
+			(link_ecoding_cap == DP_CAP_ANSI_128B132B) ? "128b/132b":"8b/10b", mst_state->mgr);
+}
+EXPORT_SYMBOL(drm_dp_mst_update_slots);
+
 /**
  * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
  * @mgr: manager for this port
@@ -5222,7 +5245,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
 					 struct drm_dp_mst_topology_state *mst_state)
 {
 	struct drm_dp_vcpi_allocation *vcpi;
-	int avail_slots = 63, payload_count = 0;
+	int avail_slots = mst_state->total_avail_slots, payload_count = 0;
 
 	list_for_each_entry(vcpi, &mst_state->vcpis, next) {
 		/* Releasing VCPI is always OK-even if the port is gone */
@@ -5251,7 +5274,7 @@ drm_dp_mst_atomic_check_vcpi_alloc_limit(struct drm_dp_mst_topology_mgr *mgr,
 		}
 	}
 	drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p VCPI avail=%d used=%d\n",
-		       mgr, mst_state, avail_slots, 63 - avail_slots);
+		       mgr, mst_state, avail_slots, mst_state->total_avail_slots - avail_slots);
 
 	return 0;
 }
@@ -5528,6 +5551,9 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
 	if (mst_state == NULL)
 		return -ENOMEM;
 
+	mst_state->total_avail_slots = 63;
+	mst_state->start_slot = 1;
+
 	mst_state->mgr = mgr;
 	INIT_LIST_HEAD(&mst_state->vcpis);
 
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index b170e272bdee..d3a24189a12c 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -368,7 +368,7 @@ static void intel_mst_disable_dp(struct intel_atomic_state *state,
 
 	drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, connector->port);
 
-	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
+	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
 	if (ret) {
 		drm_dbg_kms(&i915->drm, "failed to update payload %d\n", ret);
 	}
@@ -516,7 +516,7 @@ static void intel_mst_pre_enable_dp(struct intel_atomic_state *state,
 
 	intel_dp->active_mst_links++;
 
-	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
+	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr, 1);
 
 	/*
 	 * Before Gen 12 this is not done as part of
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index f949767698fc..6c8c59c26dbf 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -1413,7 +1413,7 @@ nv50_mstm_prepare(struct nv50_mstm *mstm)
 	int ret;
 
 	NV_ATOMIC(drm, "%s: mstm prepare\n", mstm->outp->base.base.name);
-	ret = drm_dp_update_payload_part1(&mstm->mgr);
+	ret = drm_dp_update_payload_part1(&mstm->mgr, 1);
 
 	drm_for_each_encoder(encoder, mstm->outp->base.base.dev) {
 		if (encoder->encoder_type == DRM_MODE_ENCODER_DPMST) {
diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c
index ec867fa880a4..751c2c075e09 100644
--- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
+++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
@@ -423,7 +423,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
 		drm_dp_mst_allocate_vcpi(&radeon_connector->mst_port->mst_mgr,
 					 radeon_connector->port,
 					 mst_enc->pbn, slots);
-		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
+		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
 
 		radeon_dp_mst_set_be_cntl(primary, mst_enc,
 					  radeon_connector->mst_port->hpd.hpd, true);
@@ -452,7 +452,7 @@ radeon_mst_encoder_dpms(struct drm_encoder *encoder, int mode)
 			return;
 
 		drm_dp_mst_reset_vcpi_slots(&radeon_connector->mst_port->mst_mgr, mst_enc->port);
-		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr);
+		drm_dp_update_payload_part1(&radeon_connector->mst_port->mst_mgr, 1);
 
 		drm_dp_check_act_status(&radeon_connector->mst_port->mst_mgr);
 		/* and this can also fail */
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index ddb9231d0309..3207b49586fc 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -554,6 +554,8 @@ struct drm_dp_mst_topology_state {
 	struct drm_private_state base;
 	struct list_head vcpis;
 	struct drm_dp_mst_topology_mgr *mgr;
+	u8 total_avail_slots;
+	u8 start_slot;
 };
 
 #define to_dp_mst_topology_mgr(x) container_of(x, struct drm_dp_mst_topology_mgr, base)
@@ -806,6 +808,7 @@ int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp
 
 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
 
+void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_ecoding_cap);
 
 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 				struct drm_dp_mst_port *port);
@@ -815,7 +818,7 @@ int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
 			   int pbn);
 
 
-int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr, int start_slot);
 
 
 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);
-- 
2.25.1