diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index e3497bc494944e34de6103eaaeaf47e21046b937..88db6d7e1a36b46348e21f4e30a3deb2166a96e0 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -3011,21 +3011,42 @@ static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
}
/**
- * drm_dp_atomic_find_vcpi_slots() - Find and add vcpi slots to the state
+ * drm_dp_atomic_find_vcpi_slots() - Find and add VCPI slots to the state
* @state: global atomic state
* @mgr: MST topology manager for the port
* @port: port to find vcpi slots for
* @pbn: bandwidth required for the mode in PBN
*
- * RETURNS:
- * Total slots in the atomic state assigned for this port or error
+ * Allocates VCPI slots to @port, replacing any previous VCPI allocations it
+ * may have had. Any atomic drivers which support MST must call this function
+ * in their &drm_encoder_helper_funcs.atomic_check() callback to change the
+ * current VCPI allocation for the new state, but only when
+ * &drm_crtc_state.mode_changed or &drm_crtc_state.connectors_changed is set
+ * to ensure compatibility with userspace applications that still use the
+ * legacy modesetting UAPI.
+ *
+ * Allocations set by this function are not checked against the bandwidth
+ * restraints of @mgr until the driver calls drm_dp_mst_atomic_check().
+ *
+ * Additionally, it is OK to call this function multiple times on the same
+ * @port as needed. It is not OK however, to call this function and
+ * drm_dp_atomic_release_vcpi_slots() in the same atomic check phase.
+ *
+ * See also:
+ * drm_dp_atomic_release_vcpi_slots()
+ * drm_dp_mst_atomic_check()
+ *
+ * Returns:
+ * Total slots in the atomic state assigned for this port, or a negative error
+ * code if the port no longer exists
*/
int drm_dp_atomic_find_vcpi_slots(struct drm_atomic_state *state,
struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_mst_port *port, int pbn)
{
struct drm_dp_mst_topology_state *topology_state;
- int req_slots;
+ struct drm_dp_vcpi_allocation *pos, *vcpi = NULL;
+ int prev_slots, req_slots, ret;
topology_state = drm_atomic_get_mst_topology_state(state, mgr);
if (IS_ERR(topology_state))
@@ -3034,20 +3055,54 @@ int drm_dp_atomic_find_vcpi_slots(struct drm_atomic_state *state,
port = drm_dp_mst_topology_get_port_validated(mgr, port);
if (port == NULL)
return -EINVAL;
- req_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
- DRM_DEBUG_KMS("vcpi slots req=%d, avail=%d\n",
- req_slots, topology_state->avail_slots);
- if (req_slots > topology_state->avail_slots) {
- drm_dp_mst_topology_put_port(port);
- return -ENOSPC;
+ /* Find the current allocation for this port, if any */
+ list_for_each_entry(pos, &topology_state->vcpis, next) {
+ if (pos->port == port) {
+ vcpi = pos;
+ prev_slots = vcpi->vcpi;
+
+ /*
+ * This should never happen, unless the driver tries
+ * releasing and allocating the same VCPI allocation,
+ * which is an error
+ */
+ if (WARN_ON(!prev_slots)) {
+ DRM_ERROR("cannot allocate and release VCPI on [MST PORT:%p] in the same state\n",
+ port);
+ return -EINVAL;
+ }
+
+ break;
+ }
}
+ if (!vcpi)
+ prev_slots = 0;
+
+ req_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
+
+ DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] [MST PORT:%p] VCPI %d -> %d\n",
+ port->connector->base.id, port->connector->name,
+ port, prev_slots, req_slots);
+
+ /* Add the new allocation to the state */
+ if (!vcpi) {
+ vcpi = kzalloc(sizeof(*vcpi), GFP_KERNEL);
+ if (!vcpi) {
+ ret = -ENOMEM;
+ goto out;
+ }
- topology_state->avail_slots -= req_slots;
- DRM_DEBUG_KMS("vcpi slots avail=%d", topology_state->avail_slots);
+ drm_dp_mst_get_port_malloc(port);
+ vcpi->port = port;
+ list_add(&vcpi->next, &topology_state->vcpis);
+ }
+ vcpi->vcpi = req_slots;
+ ret = req_slots;
+out:
drm_dp_mst_topology_put_port(port);
- return req_slots;
+ return ret;
}
EXPORT_SYMBOL(drm_dp_atomic_find_vcpi_slots);
@@ -3055,31 +3110,57 @@ EXPORT_SYMBOL(drm_dp_atomic_find_vcpi_slots);
* drm_dp_atomic_release_vcpi_slots() - Release allocated vcpi slots
* @state: global atomic state
* @mgr: MST topology manager for the port
- * @slots: number of vcpi slots to release
+ * @port: The port to release the VCPI slots from
*
- * RETURNS:
- * 0 if @slots were added back to &drm_dp_mst_topology_state->avail_slots or
- * negative error code
+ * Releases any VCPI slots that have been allocated to a port in the atomic
+ * state. Any atomic drivers which support MST must call this function in
+ * their &drm_connector_helper_funcs.atomic_check() callback when the
+ * connector will no longer have VCPI allocated (e.g. because it's CRTC was
+ * removed) when it had VCPI allocated in the previous atomic state.
+ *
+ * It is OK to call this even if @port has been removed from the system.
+ * Additionally, it is OK to call this function multiple times on the same
+ * @port as needed. It is not OK however, to call this function and
+ * drm_dp_atomic_find_vcpi_slots() on the same @port in a single atomic check
+ * phase.
+ *
+ * See also:
+ * drm_dp_atomic_find_vcpi_slots()
+ * drm_dp_mst_atomic_check()
+ *
+ * Returns:
+ * 0 if all slots for this port were added back to
+ * &drm_dp_mst_topology_state.avail_slots or negative error code
*/
int drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
struct drm_dp_mst_topology_mgr *mgr,
- int slots)
+ struct drm_dp_mst_port *port)
{
struct drm_dp_mst_topology_state *topology_state;
+ struct drm_dp_vcpi_allocation *pos;
+ bool found = false;
topology_state = drm_atomic_get_mst_topology_state(state, mgr);
if (IS_ERR(topology_state))
return PTR_ERR(topology_state);
- /* We cannot rely on port->vcpi.num_slots to update
- * topology_state->avail_slots as the port may not exist if the parent
- * branch device was unplugged. This should be fixed by tracking
- * per-port slot allocation in drm_dp_mst_topology_state instead of
- * depending on the caller to tell us how many slots to release.
- */
- topology_state->avail_slots += slots;
- DRM_DEBUG_KMS("vcpi slots released=%d, avail=%d\n",
- slots, topology_state->avail_slots);
+ list_for_each_entry(pos, &topology_state->vcpis, next) {
+ if (pos->port == port) {
+ found = true;
+ break;
+ }
+ }
+ if (WARN_ON(!found)) {
+ DRM_ERROR("no VCPI for [MST PORT:%p] found in mst state %p\n",
+ port, &topology_state->base);
+ return -EINVAL;
+ }
+
+ DRM_DEBUG_ATOMIC("[MST PORT:%p] VCPI %d -> 0\n", port, pos->vcpi);
+ if (pos->vcpi) {
+ drm_dp_mst_put_port_malloc(port);
+ pos->vcpi = 0;
+ }
return 0;
}
@@ -3501,15 +3582,41 @@ static void drm_dp_destroy_connector_work(struct work_struct *work)
static struct drm_private_state *
drm_dp_mst_duplicate_state(struct drm_private_obj *obj)
{
- struct drm_dp_mst_topology_state *state;
+ struct drm_dp_mst_topology_state *state, *old_state =
+ to_dp_mst_topology_state(obj->state);
+ struct drm_dp_vcpi_allocation *pos, *vcpi;
- state = kmemdup(obj->state, sizeof(*state), GFP_KERNEL);
+ state = kmemdup(old_state, sizeof(*state), GFP_KERNEL);
if (!state)
return NULL;
__drm_atomic_helper_private_obj_duplicate_state(obj, &state->base);
+ INIT_LIST_HEAD(&state->vcpis);
+
+ list_for_each_entry(pos, &old_state->vcpis, next) {
+ /* Prune leftover freed VCPI allocations */
+ if (!pos->vcpi)
+ continue;
+
+ vcpi = kmemdup(pos, sizeof(*vcpi), GFP_KERNEL);
+ if (!vcpi)
+ goto fail;
+
+ drm_dp_mst_get_port_malloc(vcpi->port);
+ list_add(&vcpi->next, &state->vcpis);
+ }
+
return &state->base;
+
+fail:
+ list_for_each_entry_safe(pos, vcpi, &state->vcpis, next) {
+ drm_dp_mst_put_port_malloc(pos->port);
+ kfree(pos);
+ }
+ kfree(state);
+
+ return NULL;
}
static void drm_dp_mst_destroy_state(struct drm_private_obj *obj,
@@ -3517,10 +3624,88 @@ static void drm_dp_mst_destroy_state(struct drm_private_obj *obj,
{
struct drm_dp_mst_topology_state *mst_state =
to_dp_mst_topology_state(state);
+ struct drm_dp_vcpi_allocation *pos, *tmp;
+
+ list_for_each_entry_safe(pos, tmp, &mst_state->vcpis, next) {
+ /* We only keep references to ports with non-zero VCPIs */
+ if (pos->vcpi)
+ drm_dp_mst_put_port_malloc(pos->port);
+ kfree(pos);
+ }
kfree(mst_state);
}
+static inline int
+drm_dp_mst_atomic_check_topology_state(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;
+
+ list_for_each_entry(vcpi, &mst_state->vcpis, next) {
+ /* Releasing VCPI is always OK-even if the port is gone */
+ if (!vcpi->vcpi) {
+ DRM_DEBUG_ATOMIC("[MST PORT:%p] releases all VCPI slots\n",
+ vcpi->port);
+ continue;
+ }
+
+ DRM_DEBUG_ATOMIC("[MST PORT:%p] requires %d vcpi slots\n",
+ vcpi->port, vcpi->vcpi);
+
+ avail_slots -= vcpi->vcpi;
+ if (avail_slots < 0) {
+ DRM_DEBUG_ATOMIC("[MST PORT:%p] not enough VCPI slots in mst state %p (avail=%d)\n",
+ vcpi->port, mst_state,
+ avail_slots + vcpi->vcpi);
+ return -ENOSPC;
+ }
+ }
+ DRM_DEBUG_ATOMIC("[MST MGR:%p] mst state %p VCPI avail=%d used=%d\n",
+ mgr, mst_state, avail_slots,
+ 63 - avail_slots);
+
+ return 0;
+}
+
+/**
+ * drm_dp_mst_atomic_check - Check that the new state of an MST topology in an
+ * atomic update is valid
+ * @state: Pointer to the new &struct drm_dp_mst_topology_state
+ *
+ * Checks the given topology state for an atomic update to ensure that it's
+ * valid. This includes checking whether there's enough bandwidth to support
+ * the new VCPI allocations in the atomic update.
+ *
+ * Any atomic drivers supporting DP MST must make sure to call this after
+ * checking the rest of their state in their
+ * &drm_mode_config_funcs.atomic_check() callback.
+ *
+ * See also:
+ * drm_dp_atomic_find_vcpi_slots()
+ * drm_dp_atomic_release_vcpi_slots()
+ *
+ * Returns:
+ *
+ * 0 if the new state is valid, negative error code otherwise.
+ */
+int drm_dp_mst_atomic_check(struct drm_atomic_state *state)
+{
+ struct drm_dp_mst_topology_mgr *mgr;
+ struct drm_dp_mst_topology_state *mst_state;
+ int i, ret = 0;
+
+ for_each_new_mst_mgr_in_state(state, mgr, mst_state, i) {
+ ret = drm_dp_mst_atomic_check_topology_state(mgr, mst_state);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(drm_dp_mst_atomic_check);
+
const struct drm_private_state_funcs drm_dp_mst_topology_state_funcs = {
.atomic_duplicate_state = drm_dp_mst_duplicate_state,
.atomic_destroy_state = drm_dp_mst_destroy_state,
@@ -3603,9 +3788,7 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
return -ENOMEM;
mst_state->mgr = mgr;
-
- /* max. time slots - one slot for MTP header */
- mst_state->avail_slots = 63;
+ INIT_LIST_HEAD(&mst_state->vcpis);
drm_atomic_private_obj_init(dev, &mgr->base,
&mst_state->base,
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 812ec5ae5c7b4617d2ce2f92fb8726f300c76c2e..5a679af03a04a4ea91ca61e3f67024ba9a7d0a6f 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -12623,6 +12623,10 @@ static int intel_atomic_check(struct drm_device *dev,
"[modeset]" : "[fastset]");
}
+ ret = drm_dp_mst_atomic_check(state);
+ if (ret)
+ return ret;
+
if (any_ms) {
ret = intel_modeset_checks(state);
diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index 631fd1537252427a25109793e9fbdc1d09334419..c8e2215628e67ab6bcc1b8c7443b7ed3769c216b 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -41,8 +41,12 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
struct drm_connector *connector = conn_state->connector;
void *port = to_intel_connector(connector)->port;
struct drm_atomic_state *state = pipe_config->base.state;
+ struct drm_crtc *crtc = pipe_config->base.crtc;
+ struct drm_crtc_state *old_crtc_state =
+ drm_atomic_get_old_crtc_state(state, crtc);
int bpp;
- int lane_count, slots = 0;
+ int lane_count, slots =
+ to_intel_crtc_state(old_crtc_state)->dp_m_n.tu;
const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
int mst_pbn;
bool constant_n = drm_dp_has_quirk(&intel_dp->desc,
@@ -107,35 +111,39 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
return true;
}
-static int intel_dp_mst_atomic_check(struct drm_connector *connector,
- struct drm_connector_state *new_conn_state)
+static int
+intel_dp_mst_atomic_check(struct drm_connector *connector,
+ struct drm_connector_state *new_conn_state)
{
struct drm_atomic_state *state = new_conn_state->state;
- struct drm_connector_state *old_conn_state;
- struct drm_crtc *old_crtc;
+ struct drm_connector_state *old_conn_state =
+ drm_atomic_get_old_connector_state(state, connector);
+ struct intel_connector *intel_connector =
+ to_intel_connector(connector);
+ struct drm_crtc *new_crtc = new_conn_state->crtc;
struct drm_crtc_state *crtc_state;
- int slots, ret = 0;
+ struct drm_dp_mst_topology_mgr *mgr;
+ int ret = 0;
- old_conn_state = drm_atomic_get_old_connector_state(state, connector);
- old_crtc = old_conn_state->crtc;
- if (!old_crtc)
- return ret;
-
- crtc_state = drm_atomic_get_new_crtc_state(state, old_crtc);
- slots = to_intel_crtc_state(crtc_state)->dp_m_n.tu;
- if (drm_atomic_crtc_needs_modeset(crtc_state) && slots > 0) {
- struct drm_dp_mst_topology_mgr *mgr;
- struct drm_encoder *old_encoder;
+ if (!old_conn_state->crtc)
+ return 0;
- old_encoder = old_conn_state->best_encoder;
- mgr = &enc_to_mst(old_encoder)->primary->dp.mst_mgr;
+ /* We only want to free VCPI if this state disables the CRTC on this
+ * connector
+ */
+ if (new_crtc) {
+ crtc_state = drm_atomic_get_new_crtc_state(state, new_crtc);
- ret = drm_dp_atomic_release_vcpi_slots(state, mgr, slots);
- if (ret)
- DRM_DEBUG_KMS("failed releasing %d vcpi slots:%d\n", slots, ret);
- else
- to_intel_crtc_state(crtc_state)->dp_m_n.tu = 0;
+ if (!crtc_state ||
+ !drm_atomic_crtc_needs_modeset(crtc_state) ||
+ crtc_state->enable)
+ return 0;
}
+
+ mgr = &enc_to_mst(old_conn_state->best_encoder)->primary->dp.mst_mgr;
+ ret = drm_dp_atomic_release_vcpi_slots(state, mgr,
+ intel_connector->port);
+
return ret;
}
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index 581163c8d7d74f86b9d26b293d7c00c0a6bbf35c..451d020f0137b924218967990bf7e76a62141041 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -425,9 +425,15 @@ struct drm_dp_payload {
#define to_dp_mst_topology_state(x) container_of(x, struct drm_dp_mst_topology_state, base)
+struct drm_dp_vcpi_allocation {
+ struct drm_dp_mst_port *port;
+ int vcpi;
+ struct list_head next;
+};
+
struct drm_dp_mst_topology_state {
struct drm_private_state base;
- int avail_slots;
+ struct list_head vcpis;
struct drm_dp_mst_topology_mgr *mgr;
};
@@ -638,14 +644,17 @@ void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr);
int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr);
struct drm_dp_mst_topology_state *drm_atomic_get_mst_topology_state(struct drm_atomic_state *state,
struct drm_dp_mst_topology_mgr *mgr);
-int drm_dp_atomic_find_vcpi_slots(struct drm_atomic_state *state,
- struct drm_dp_mst_topology_mgr *mgr,
- struct drm_dp_mst_port *port, int pbn);
-int drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
- struct drm_dp_mst_topology_mgr *mgr,
- int slots);
+int __must_check
+drm_dp_atomic_find_vcpi_slots(struct drm_atomic_state *state,
+ struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port, int pbn);
+int __must_check
+drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
+ struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port);
int drm_dp_send_power_updown_phy(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_mst_port *port, bool power_up);
+int __must_check drm_dp_mst_atomic_check(struct drm_atomic_state *state);
void drm_dp_mst_get_port_malloc(struct drm_dp_mst_port *port);
void drm_dp_mst_put_port_malloc(struct drm_dp_mst_port *port);