[RESEND RFC 07/18] drm/display/dp_mst: Add helper for finding payloads in atomic MST state

Lyude Paul
2022-06-08T00:56:00Z

We already open-code this quite often, and will be iterating through
payloads even more once we've moved all of the payload tracking into the
atomic state. So, let's add a helper for doing this.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Wayne Lin <Wayne.Lin@amd.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Fangzhi Zuo <Jerry.Zuo@amd.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sean Paul <sean@poorly.run>
---
drivers/gpu/drm/display/drm_dp_mst_topology.c | 109 ++++++++----------
1 file changed, 45 insertions(+), 64 deletions(-)

diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index ec52f91b1f0e..0bc2c7a90c37 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -1737,6 +1737,19 @@ drm_dp_mst_dump_port_topology_history(struct drm_dp_mst_port *port) {}
#define save_port_topology_ref(port, type)
#endif

+static struct drm_dp_mst_atomic_payload *
+drm_atomic_get_mst_payload_state(struct drm_dp_mst_topology_state *state,
+ struct drm_dp_mst_port *port)
+{
+ struct drm_dp_mst_atomic_payload *payload;
+
+ list_for_each_entry(payload, &state->payloads, next)
+ if (payload->port == port)
+ return payload;
+
+ return NULL;
+}
+
static void drm_dp_destroy_mst_branch_device(struct kref *kref)
{
struct drm_dp_mst_branch *mstb =
@@ -4381,39 +4394,31 @@ int drm_dp_atomic_find_time_slots(struct drm_atomic_state *state,
int pbn_div)
{
struct drm_dp_mst_topology_state *topology_state;
- struct drm_dp_mst_atomic_payload *pos, *payload = NULL;
- int prev_slots, prev_bw, req_slots;
+ struct drm_dp_mst_atomic_payload *payload = NULL;
+ int prev_slots = 0, prev_bw = 0, req_slots;

topology_state = drm_atomic_get_mst_topology_state(state, mgr);
if (IS_ERR(topology_state))
return PTR_ERR(topology_state);

/* Find the current allocation for this port, if any */
- list_for_each_entry(pos, &topology_state->payloads, next) {
- if (pos->port == port) {
- payload = pos;
- prev_slots = payload->time_slots;
- prev_bw = payload->pbn;
-
- /*
- * This should never happen, unless the driver tries
- * releasing and allocating the same timeslot allocation,
- * which is an error
- */
- if (WARN_ON(!prev_slots)) {
- drm_err(mgr->dev,
- "cannot allocate and release time slots on [MST PORT:%p] in the same state\n",
- port);
- return -EINVAL;
- }
+ payload = drm_atomic_get_mst_payload_state(topology_state, port);
+ if (payload) {
+ prev_slots = payload->time_slots;
+ prev_bw = payload->pbn;

- break;
+ /*
+ * This should never happen, unless the driver tries
+ * releasing and allocating the same timeslot allocation,
+ * which is an error
+ */
+ if (WARN_ON(!prev_slots)) {
+ drm_err(mgr->dev,
+ "cannot allocate and release time slots on [MST PORT:%p] in the same state\n",
+ port);
+ return -EINVAL;
}
}
- if (!payload) {
- prev_slots = 0;
- prev_bw = 0;
- }

if (pbn_div <= 0)
pbn_div = mgr->pbn_div;
@@ -4474,30 +4479,24 @@ int drm_dp_atomic_release_time_slots(struct drm_atomic_state *state,
struct drm_dp_mst_port *port)
{
struct drm_dp_mst_topology_state *topology_state;
- struct drm_dp_mst_atomic_payload *pos;
- bool found = false;
+ struct drm_dp_mst_atomic_payload *payload;

topology_state = drm_atomic_get_mst_topology_state(state, mgr);
if (IS_ERR(topology_state))
return PTR_ERR(topology_state);

- list_for_each_entry(pos, &topology_state->payloads, next) {
- if (pos->port == port) {
- found = true;
- break;
- }
- }
- if (WARN_ON(!found)) {
+ payload = drm_atomic_get_mst_payload_state(topology_state, port);
+ if (WARN_ON(!payload)) {
drm_err(mgr->dev, "No payload for [MST PORT:%p] found in mst state %p\n",
port, &topology_state->base);
return -EINVAL;
}

- drm_dbg_atomic(mgr->dev, "[MST PORT:%p] TU %d -> 0\n", port, pos->time_slots);
- if (pos->time_slots) {
+ drm_dbg_atomic(mgr->dev, "[MST PORT:%p] TU %d -> 0\n", port, payload->time_slots);
+ if (payload->time_slots) {
drm_dp_mst_put_port_malloc(port);
- pos->time_slots = 0;
- pos->pbn = 0;
+ payload->time_slots = 0;
+ payload->pbn = 0;
}

return 0;
@@ -5194,18 +5193,8 @@ drm_dp_mst_atomic_check_port_bw_limit(struct drm_dp_mst_port *port,
return 0;

if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) {
- bool found = false;
-
- list_for_each_entry(payload, &state->payloads, next) {
- if (payload->port != port)
- continue;
- if (!payload->pbn)
- return 0;
-
- found = true;
- break;
- }
- if (!found)
+ payload = drm_atomic_get_mst_payload_state(state, port);
+ if (!payload)
return 0;

/*
@@ -5360,34 +5349,26 @@ int drm_dp_mst_atomic_enable_dsc(struct drm_atomic_state *state,
bool enable)
{
struct drm_dp_mst_topology_state *mst_state;
- struct drm_dp_mst_atomic_payload *pos;
- bool found = false;
+ struct drm_dp_mst_atomic_payload *payload;
int time_slots = 0;

mst_state = drm_atomic_get_mst_topology_state(state, port->mgr);
-
if (IS_ERR(mst_state))
return PTR_ERR(mst_state);

- list_for_each_entry(pos, &mst_state->payloads, next) {
- if (pos->port == port) {
- found = true;
- break;
- }
- }
-
- if (!found) {
+ payload = drm_atomic_get_mst_payload_state(mst_state, port);
+ if (!payload) {
drm_dbg_atomic(state->dev,
"[MST PORT:%p] Couldn't find payload in mst state %p\n",
port, mst_state);
return -EINVAL;
}

- if (pos->dsc_enabled == enable) {
+ if (payload->dsc_enabled == enable) {
drm_dbg_atomic(state->dev,
"[MST PORT:%p] DSC flag is already set to %d, returning %d time slots\n",
- port, enable, pos->time_slots);
- time_slots = pos->time_slots;
+ port, enable, payload->time_slots);
+ time_slots = payload->time_slots;
}

if (enable) {
@@ -5399,7 +5380,7 @@ int drm_dp_mst_atomic_enable_dsc(struct drm_atomic_state *state,
return -EINVAL;
}

- pos->dsc_enabled = enable;
+ payload->dsc_enabled = enable;

return time_slots;
}
--
2.35.3