2021-06-28 09:19:24

by Sam McNally

[permalink] [raw]
Subject: [PATCH v7 1/3] drm/dp_mst: Add self-tests for up requests

Up requests are decoded by drm_dp_sideband_parse_req(), which operates
on a drm_dp_sideband_msg_rx, unlike down requests. Expand the existing
self-test helper sideband_msg_req_encode_decode() to copy the message
contents and length from a drm_dp_sideband_msg_tx to
drm_dp_sideband_msg_rx and use the parse function under test in place of
decode. Add an additional helper for testing clearly-invalid up
messages, verifying that parse rejects them.

Add support for currently-supported up requests to
drm_dp_dump_sideband_msg_req_body(); add support to
drm_dp_encode_sideband_req() to allow encoding for the self-tests.

Add self-tests for CONNECTION_STATUS_NOTIFY and RESOURCE_STATUS_NOTIFY.

Reviewed-by: Lyude Paul <[email protected]>
Signed-off-by: Sam McNally <[email protected]>
---

(no changes since v5)

Changes in v5:
- Set mock device name to more clearly attribute error/debug logging to
the self-test, in particular for cases where failures are expected

Changes in v4:
- New in v4

drivers/gpu/drm/drm_dp_mst_topology.c | 54 ++++++-
.../gpu/drm/drm_dp_mst_topology_internal.h | 4 +
.../drm/selftests/test-drm_dp_mst_helper.c | 149 ++++++++++++++++--
3 files changed, 192 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index ad0795afc21c..ee58f6517482 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -445,6 +445,37 @@ drm_dp_encode_sideband_req(const struct drm_dp_sideband_msg_req_body *req,
idx++;
}
break;
+ case DP_CONNECTION_STATUS_NOTIFY: {
+ const struct drm_dp_connection_status_notify *msg;
+
+ msg = &req->u.conn_stat;
+ buf[idx] = (msg->port_number & 0xf) << 4;
+ idx++;
+ memcpy(&raw->msg[idx], msg->guid, 16);
+ idx += 16;
+ raw->msg[idx] = 0;
+ raw->msg[idx] |= msg->legacy_device_plug_status ? BIT(6) : 0;
+ raw->msg[idx] |= msg->displayport_device_plug_status ? BIT(5) : 0;
+ raw->msg[idx] |= msg->message_capability_status ? BIT(4) : 0;
+ raw->msg[idx] |= msg->input_port ? BIT(3) : 0;
+ raw->msg[idx] |= FIELD_PREP(GENMASK(2, 0), msg->peer_device_type);
+ idx++;
+ break;
+ }
+ case DP_RESOURCE_STATUS_NOTIFY: {
+ const struct drm_dp_resource_status_notify *msg;
+
+ msg = &req->u.resource_stat;
+ buf[idx] = (msg->port_number & 0xf) << 4;
+ idx++;
+ memcpy(&raw->msg[idx], msg->guid, 16);
+ idx += 16;
+ buf[idx] = (msg->available_pbn & 0xff00) >> 8;
+ idx++;
+ buf[idx] = (msg->available_pbn & 0xff);
+ idx++;
+ break;
+ }
}
raw->cur_len = idx;
}
@@ -675,6 +706,22 @@ drm_dp_dump_sideband_msg_req_body(const struct drm_dp_sideband_msg_req_body *req
req->u.enc_status.stream_behavior,
req->u.enc_status.valid_stream_behavior);
break;
+ case DP_CONNECTION_STATUS_NOTIFY:
+ P("port=%d guid=%*ph legacy=%d displayport=%d messaging=%d input=%d peer_type=%d",
+ req->u.conn_stat.port_number,
+ (int)ARRAY_SIZE(req->u.conn_stat.guid), req->u.conn_stat.guid,
+ req->u.conn_stat.legacy_device_plug_status,
+ req->u.conn_stat.displayport_device_plug_status,
+ req->u.conn_stat.message_capability_status,
+ req->u.conn_stat.input_port,
+ req->u.conn_stat.peer_device_type);
+ break;
+ case DP_RESOURCE_STATUS_NOTIFY:
+ P("port=%d guid=%*ph pbn=%d",
+ req->u.resource_stat.port_number,
+ (int)ARRAY_SIZE(req->u.resource_stat.guid), req->u.resource_stat.guid,
+ req->u.resource_stat.available_pbn);
+ break;
default:
P("???\n");
break;
@@ -1119,9 +1166,9 @@ static bool drm_dp_sideband_parse_resource_status_notify(const struct drm_dp_mst
return false;
}

-static bool drm_dp_sideband_parse_req(const struct drm_dp_mst_topology_mgr *mgr,
- struct drm_dp_sideband_msg_rx *raw,
- struct drm_dp_sideband_msg_req_body *msg)
+bool drm_dp_sideband_parse_req(const struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_req_body *msg)
{
memset(msg, 0, sizeof(*msg));
msg->req_type = (raw->msg[0] & 0x7f);
@@ -1137,6 +1184,7 @@ static bool drm_dp_sideband_parse_req(const struct drm_dp_mst_topology_mgr *mgr,
return false;
}
}
+EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_dp_sideband_parse_req);

static void build_dpcd_write(struct drm_dp_sideband_msg_tx *msg,
u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology_internal.h b/drivers/gpu/drm/drm_dp_mst_topology_internal.h
index eeda9a61c657..0356a2e0dba1 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology_internal.h
+++ b/drivers/gpu/drm/drm_dp_mst_topology_internal.h
@@ -21,4 +21,8 @@ void
drm_dp_dump_sideband_msg_req_body(const struct drm_dp_sideband_msg_req_body *req,
int indent, struct drm_printer *printer);

+bool
+drm_dp_sideband_parse_req(const struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_req_body *msg);
#endif /* !_DRM_DP_MST_HELPER_INTERNAL_H_ */
diff --git a/drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c b/drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c
index 6b4759ed6bfd..7bbeb1e5bc97 100644
--- a/drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c
+++ b/drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c
@@ -13,6 +13,10 @@
#include "../drm_dp_mst_topology_internal.h"
#include "test-drm_modeset_common.h"

+static void mock_release(struct device *dev)
+{
+}
+
int igt_dp_mst_calc_pbn_mode(void *ignored)
{
int pbn, i;
@@ -120,27 +124,60 @@ sideband_msg_req_equal(const struct drm_dp_sideband_msg_req_body *in,
static bool
sideband_msg_req_encode_decode(struct drm_dp_sideband_msg_req_body *in)
{
- struct drm_dp_sideband_msg_req_body *out;
+ struct drm_dp_sideband_msg_req_body *out = NULL;
struct drm_printer p = drm_err_printer(PREFIX_STR);
- struct drm_dp_sideband_msg_tx *txmsg;
+ struct drm_dp_sideband_msg_tx *txmsg = NULL;
+ struct drm_dp_sideband_msg_rx *rxmsg = NULL;
+ struct drm_dp_mst_topology_mgr *mgr = NULL;
int i, ret;
- bool result = true;
+ bool result = false;

out = kzalloc(sizeof(*out), GFP_KERNEL);
if (!out)
- return false;
+ goto out;

txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
if (!txmsg)
- return false;
+ goto out;

- drm_dp_encode_sideband_req(in, txmsg);
- ret = drm_dp_decode_sideband_req(txmsg, out);
- if (ret < 0) {
- drm_printf(&p, "Failed to decode sideband request: %d\n",
- ret);
- result = false;
+ rxmsg = kzalloc(sizeof(*rxmsg), GFP_KERNEL);
+ if (!rxmsg)
goto out;
+
+ mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
+ if (!mgr)
+ goto out;
+
+ mgr->dev = kzalloc(sizeof(*mgr->dev), GFP_KERNEL);
+ if (!mgr->dev)
+ goto out;
+
+ mgr->dev->dev = kzalloc(sizeof(*mgr->dev->dev), GFP_KERNEL);
+ if (!mgr->dev->dev)
+ goto out;
+
+ mgr->dev->dev->release = mock_release;
+ mgr->dev->dev->init_name = PREFIX_STR;
+ device_initialize(mgr->dev->dev);
+
+ drm_dp_encode_sideband_req(in, txmsg);
+ switch (in->req_type) {
+ case DP_CONNECTION_STATUS_NOTIFY:
+ case DP_RESOURCE_STATUS_NOTIFY:
+ memcpy(&rxmsg->msg, txmsg->msg, ARRAY_SIZE(rxmsg->msg));
+ rxmsg->curlen = txmsg->cur_len;
+ if (!drm_dp_sideband_parse_req(mgr, rxmsg, out)) {
+ drm_printf(&p, "Failed to decode sideband request\n");
+ goto out;
+ }
+ break;
+ default:
+ ret = drm_dp_decode_sideband_req(txmsg, out);
+ if (ret < 0) {
+ drm_printf(&p, "Failed to decode sideband request: %d\n", ret);
+ goto out;
+ }
+ break;
}

if (!sideband_msg_req_equal(in, out)) {
@@ -148,9 +185,9 @@ sideband_msg_req_encode_decode(struct drm_dp_sideband_msg_req_body *in)
drm_dp_dump_sideband_msg_req_body(in, 1, &p);
drm_printf(&p, "Got:\n");
drm_dp_dump_sideband_msg_req_body(out, 1, &p);
- result = false;
goto out;
}
+ result = true;

switch (in->req_type) {
case DP_REMOTE_DPCD_WRITE:
@@ -171,6 +208,66 @@ sideband_msg_req_encode_decode(struct drm_dp_sideband_msg_req_body *in)
out:
kfree(out);
kfree(txmsg);
+ kfree(rxmsg);
+ if (mgr) {
+ if (mgr->dev) {
+ put_device(mgr->dev->dev);
+ kfree(mgr->dev);
+ }
+ kfree(mgr);
+ }
+ return result;
+}
+
+static bool
+sideband_msg_req_parse(int req_type)
+{
+ struct drm_dp_sideband_msg_req_body *out = NULL;
+ struct drm_printer p = drm_err_printer(PREFIX_STR);
+ struct drm_dp_sideband_msg_rx *rxmsg = NULL;
+ struct drm_dp_mst_topology_mgr *mgr = NULL;
+ bool result = false;
+
+ out = kzalloc(sizeof(*out), GFP_KERNEL);
+ if (!out)
+ goto out;
+
+ rxmsg = kzalloc(sizeof(*rxmsg), GFP_KERNEL);
+ if (!rxmsg)
+ goto out;
+
+ mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
+ if (!mgr)
+ goto out;
+
+ mgr->dev = kzalloc(sizeof(*mgr->dev), GFP_KERNEL);
+ if (!mgr->dev)
+ goto out;
+
+ mgr->dev->dev = kzalloc(sizeof(*mgr->dev->dev), GFP_KERNEL);
+ if (!mgr->dev->dev)
+ goto out;
+
+ mgr->dev->dev->release = mock_release;
+ mgr->dev->dev->init_name = PREFIX_STR " expected parse failure";
+ device_initialize(mgr->dev->dev);
+
+ rxmsg->curlen = 1;
+ rxmsg->msg[0] = req_type & 0x7f;
+ if (drm_dp_sideband_parse_req(mgr, rxmsg, out))
+ drm_printf(&p, "Unexpectedly decoded invalid sideband request\n");
+ else
+ result = true;
+out:
+ kfree(out);
+ kfree(rxmsg);
+ if (mgr) {
+ if (mgr->dev) {
+ put_device(mgr->dev->dev);
+ kfree(mgr->dev);
+ }
+ kfree(mgr);
+ }
return result;
}

@@ -268,6 +365,34 @@ int igt_dp_mst_sideband_msg_req_decode(void *unused)
in.u.enc_status.valid_stream_behavior = 1;
DO_TEST();

+ in.req_type = DP_CONNECTION_STATUS_NOTIFY;
+ in.u.conn_stat.port_number = 0xf;
+ get_random_bytes(in.u.conn_stat.guid, sizeof(in.u.conn_stat.guid));
+ in.u.conn_stat.legacy_device_plug_status = 1;
+ in.u.conn_stat.displayport_device_plug_status = 0;
+ in.u.conn_stat.message_capability_status = 0;
+ in.u.conn_stat.input_port = 0;
+ in.u.conn_stat.peer_device_type = 7;
+ DO_TEST();
+ in.u.conn_stat.displayport_device_plug_status = 1;
+ DO_TEST();
+ in.u.conn_stat.message_capability_status = 1;
+ DO_TEST();
+ in.u.conn_stat.input_port = 1;
+ DO_TEST();
+
+ in.req_type = DP_RESOURCE_STATUS_NOTIFY;
+ in.u.resource_stat.port_number = 0xf;
+ get_random_bytes(in.u.resource_stat.guid, sizeof(in.u.resource_stat.guid));
+ in.u.resource_stat.available_pbn = 0xcdef;
+ DO_TEST();
+
+#undef DO_TEST
+#define DO_TEST(req_type) FAIL_ON(!sideband_msg_req_parse(req_type))
+ DO_TEST(DP_CONNECTION_STATUS_NOTIFY);
+ DO_TEST(DP_RESOURCE_STATUS_NOTIFY);
+
+ DO_TEST(DP_REMOTE_I2C_WRITE);
#undef DO_TEST
return 0;
}
--
2.32.0.93.g670b81a890-goog


2021-06-28 09:22:03

by Sam McNally

[permalink] [raw]
Subject: [PATCH v7 3/3] drm_dp_cec: add MST support

With DP v2.0 errata E5, CEC tunneling can be supported through an MST
topology.

When tunneling CEC through an MST port, CEC IRQs are delivered via a
sink event notify message; when a sink event notify message is received,
trigger CEC IRQ handling - ESI1 is not used for remote CEC IRQs so its
value is not checked.

Register and unregister for all MST connectors, ensuring their
drm_dp_aux_cec struct won't be accessed uninitialized.

Reviewed-by: Hans Verkuil <[email protected]>
Reviewed-by: Lyude Paul <[email protected]>
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Sam McNally <[email protected]>
---

Changes in v7:
- Added mutex_init() for aux->cec.lock

Changes in v6:
- Removed superfluous #include <drm/drm_dp_mst_helper.h>
- Removed spurious added newlines

Changes in v4:
- Removed use of work queues
- Updated checks of aux.transfer to accept aux.is_remote

Changes in v3:
- Fixed whitespace in drm_dp_cec_mst_irq_work()
- Moved drm_dp_cec_mst_set_edid_work() with the other set_edid functions

Changes in v2:
- Used aux->is_remote instead of aux->cec.is_mst, removing the need for
the previous patch in the series
- Added a defensive check for null edid in the deferred set_edid work,
in case the edid is no longer valid at that point

drivers/gpu/drm/drm_dp_cec.c | 17 +++++++++++++----
drivers/gpu/drm/drm_dp_helper.c | 3 ++-
drivers/gpu/drm/drm_dp_mst_topology.c | 24 ++++++++++++++++++++++++
3 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_cec.c b/drivers/gpu/drm/drm_dp_cec.c
index 3ab2609f9ec7..61c59e2c4b3e 100644
--- a/drivers/gpu/drm/drm_dp_cec.c
+++ b/drivers/gpu/drm/drm_dp_cec.c
@@ -245,13 +245,22 @@ void drm_dp_cec_irq(struct drm_dp_aux *aux)
int ret;

/* No transfer function was set, so not a DP connector */
- if (!aux->transfer)
+ if (!aux->transfer && !aux->is_remote)
return;

mutex_lock(&aux->cec.lock);
if (!aux->cec.adap)
goto unlock;

+ if (aux->is_remote) {
+ /*
+ * For remote connectors, CEC IRQ is triggered by an explicit
+ * message so ESI1 is not involved.
+ */
+ drm_dp_cec_handle_irq(aux);
+ goto unlock;
+ }
+
ret = drm_dp_dpcd_readb(aux, DP_DEVICE_SERVICE_IRQ_VECTOR_ESI1,
&cec_irq);
if (ret < 0 || !(cec_irq & DP_CEC_IRQ))
@@ -307,7 +316,7 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
u8 cap;

/* No transfer function was set, so not a DP connector */
- if (!aux->transfer)
+ if (!aux->transfer && !aux->is_remote)
return;

#ifndef CONFIG_MEDIA_CEC_RC
@@ -383,7 +392,7 @@ EXPORT_SYMBOL(drm_dp_cec_set_edid);
void drm_dp_cec_unset_edid(struct drm_dp_aux *aux)
{
/* No transfer function was set, so not a DP connector */
- if (!aux->transfer)
+ if (!aux->transfer && !aux->is_remote)
return;

cancel_delayed_work_sync(&aux->cec.unregister_work);
@@ -428,7 +437,7 @@ void drm_dp_cec_register_connector(struct drm_dp_aux *aux,
struct drm_connector *connector)
{
WARN_ON(aux->cec.adap);
- if (WARN_ON(!aux->transfer))
+ if (WARN_ON(!aux->transfer && !aux->is_remote))
return;
aux->cec.connector = connector;
INIT_DELAYED_WORK(&aux->cec.unregister_work,
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 24bbc710c825..db566062058c 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -1723,10 +1723,11 @@ static void drm_dp_aux_crc_work(struct work_struct *work)
* @aux: DisplayPort AUX channel
*
* Used for remote aux channel in general. Merely initialize the crc work
- * struct.
+ * struct and CEC lock.
*/
void drm_dp_remote_aux_init(struct drm_dp_aux *aux)
{
+ mutex_init(&aux->cec.lock);
INIT_WORK(&aux->crc_work, drm_dp_aux_crc_work);
}
EXPORT_SYMBOL(drm_dp_remote_aux_init);
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 1cc1a58cfa8b..b58c884fe67b 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -2362,6 +2362,8 @@ static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb,
int drm_dp_mst_connector_late_register(struct drm_connector *connector,
struct drm_dp_mst_port *port)
{
+ drm_dp_cec_register_connector(&port->aux, connector);
+
drm_dbg_kms(port->mgr->dev, "registering %s remote bus for %s\n",
port->aux.name, connector->kdev->kobj.name);

@@ -2385,6 +2387,8 @@ void drm_dp_mst_connector_early_unregister(struct drm_connector *connector,
drm_dbg_kms(port->mgr->dev, "unregistering %s remote bus for %s\n",
port->aux.name, connector->kdev->kobj.name);
drm_dp_aux_unregister_devnode(&port->aux);
+
+ drm_dp_cec_unregister_connector(&port->aux);
}
EXPORT_SYMBOL(drm_dp_mst_connector_early_unregister);

@@ -2662,6 +2666,21 @@ drm_dp_mst_handle_conn_stat(struct drm_dp_mst_branch *mstb,
queue_work(system_long_wq, &mstb->mgr->work);
}

+static void
+drm_dp_mst_handle_sink_event(struct drm_dp_mst_branch *mstb,
+ struct drm_dp_sink_event_notify *sink_event)
+{
+ struct drm_dp_mst_port *port;
+
+ if (sink_event->event_id & DP_SINK_EVENT_CEC_IRQ_EVENT) {
+ port = drm_dp_get_port(mstb, sink_event->port_number);
+ if (port) {
+ drm_dp_cec_irq(&port->aux);
+ drm_dp_mst_topology_put_port(port);
+ }
+ }
+}
+
static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
u8 lct, u8 *rad)
{
@@ -4177,6 +4196,8 @@ drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr,
if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY) {
drm_dp_mst_handle_conn_stat(mstb, &msg->u.conn_stat);
hotplug = true;
+ } else if (msg->req_type == DP_SINK_EVENT_NOTIFY) {
+ drm_dp_mst_handle_sink_event(mstb, &msg->u.sink_event);
}

drm_dp_mst_topology_put_mstb(mstb);
@@ -4369,6 +4390,8 @@ drm_dp_mst_detect_port(struct drm_connector *connector,
break;
}
out:
+ if (ret != connector_status_connected)
+ drm_dp_cec_unset_edid(&port->aux);
drm_dp_mst_topology_put_port(port);
return ret;
}
@@ -4399,6 +4422,7 @@ struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_
edid = drm_get_edid(connector, &port->aux.ddc);
}
port->has_audio = drm_detect_monitor_audio(edid);
+ drm_dp_cec_set_edid(&port->aux, edid);
drm_dp_mst_topology_put_port(port);
return edid;
}
--
2.32.0.93.g670b81a890-goog