[PATCH] drm: Update MST First Link Slot Information Based on Encoding Format
Bhawanpreet Lakha
Bhawanpreet.Lakha at amd.com
Tue Oct 12 21:58:48 UTC 2021
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:
* Remove get_mst_link_encoding_cap
* Move total/start slots to mst_state, and copy it to mst_mgr in
atomic_check
Signed-off-by: Fangzhi Zuo <Jerry.Zuo at amd.com>
Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha at amd.com>
---
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 28 +++++++++++++++
drivers/gpu/drm/drm_dp_mst_topology.c | 35 +++++++++++++++----
include/drm/drm_dp_mst_helper.h | 13 +++++++
3 files changed, 69 insertions(+), 7 deletions(-)
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 5020f2d36fe1..4ad50eb0091a 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -10612,6 +10612,8 @@ 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);
@@ -10819,6 +10821,32 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
lock_and_validation_needed = true;
}
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+ 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_coding_cap(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/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index ad0795afc21c..fb5c47c4cb2e 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -3368,7 +3368,7 @@ int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
struct drm_dp_payload req_payload;
struct drm_dp_mst_port *port;
int i, j;
- int cur_slots = 1;
+ int cur_slots = mgr->start_slot;
bool skip;
mutex_lock(&mgr->payload_lock);
@@ -4321,7 +4321,7 @@ int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
/* max. time slots - one slot for MTP header */
- if (num_slots > 63)
+ if (num_slots > mgr->total_avail_slots)
return -ENOSPC;
return num_slots;
}
@@ -4333,7 +4333,7 @@ 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)
+ if (slots > mgr->total_avail_slots)
return -ENOSPC;
vcpi->pbn = pbn;
@@ -4507,6 +4507,18 @@ int drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
}
EXPORT_SYMBOL(drm_dp_atomic_release_vcpi_slots);
+void drm_dp_mst_update_coding_cap(struct drm_dp_mst_topology_state *mst_state, uint8_t link_coding_cap)
+{
+ if (link_coding_cap == DP_CAP_ANSI_128B132B) {
+ mst_state->total_avail_slots = 64;
+ mst_state->start_slot = 0;
+ }
+
+ DRM_DEBUG_KMS("%s coding format on mgr 0x%p\n",
+ (link_coding_cap == DP_CAP_ANSI_128B132B) ? "128b/132b":"8b/10b", mst_state->mgr);
+}
+EXPORT_SYMBOL(drm_dp_mst_update_coding_cap);
+
/**
* drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
* @mgr: manager for this port
@@ -4538,8 +4550,8 @@ 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",
- DIV_ROUND_UP(pbn, mgr->pbn_div), ret);
+ drm_dbg_kms(mgr->dev, "failed to init vcpi slots=%d max=%d ret=%d\n",
+ DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->total_avail_slots, ret);
drm_dp_mst_topology_put_port(port);
goto out;
}
@@ -5226,7 +5238,7 @@ 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 = mgr->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 */
@@ -5255,7 +5267,7 @@ 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, mgr->total_avail_slots - avail_slots);
return 0;
}
@@ -5421,6 +5433,10 @@ int drm_dp_mst_atomic_check(struct drm_atomic_state *state)
break;
mutex_lock(&mgr->lock);
+
+ mgr->start_slot = mst_state->start_slot;
+ mgr->total_avail_slots = mst_state->total_avail_slots;
+
ret = drm_dp_mst_atomic_check_mstb_bw_limit(mgr->mst_primary,
mst_state);
mutex_unlock(&mgr->lock);
@@ -5527,11 +5543,16 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
if (!mgr->proposed_vcpis)
return -ENOMEM;
set_bit(0, &mgr->payload_mask);
+ mgr->total_avail_slots = 63;
+ mgr->start_slot = 1;
mst_state = kzalloc(sizeof(*mst_state), GFP_KERNEL);
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/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index ddb9231d0309..f8152dfb34ed 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)
@@ -661,6 +663,16 @@ struct drm_dp_mst_topology_mgr {
*/
int pbn_div;
+ /**
+ * @total_avail_slots: 63 for 8b/10b, 64 for 128/132b
+ */
+ u8 total_avail_slots;
+
+ /**
+ * @start_slot: 1 for 8b/10b, 0 for 128/132b
+ */
+ u8 start_slot;
+
/**
* @funcs: Atomic helper callbacks
*/
@@ -806,6 +818,7 @@ 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_coding_cap(struct drm_dp_mst_topology_state *mst_state, uint8_t link_coding_cap);
void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_mst_port *port);
--
2.25.1
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