[PATCH v8.5] drm/mst: Add support for QUERY_STREAM_ENCRYPTION_STATUS MST sideband message
Sean Paul
sean at poorly.run
Wed Aug 19 14:31:24 UTC 2020
From: Sean Paul <seanpaul at chromium.org>
Used to query whether an MST stream is encrypted or not.
Cc: Lyude Paul <lyude at redhat.com>
Reviewed-by: Anshuman Gupta <anshuman.gupta at intel.com>
Reviewed-by: Lyude Paul <lyude at redhat.com>
Signed-off-by: Sean Paul <seanpaul at chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218220242.107265-14-sean@poorly.run #v4
Link: https://patchwork.freedesktop.org/patch/msgid/20200305201236.152307-15-sean@poorly.run #v5
Link: https://patchwork.freedesktop.org/patch/msgid/20200429195502.39919-15-sean@poorly.run #v6
Link: https://patchwork.freedesktop.org/patch/msgid/20200623155907.22961-16-sean@poorly.run #v7
Link: https://patchwork.freedesktop.org/patch/msgid/20200818153910.27894-16-sean@poorly.run #v8
Changes in v4:
-Added to the set
Changes in v5:
-None
Changes in v6:
-Use FIELD_PREP to generate request buffer bitfields (Lyude)
-Add mst selftest and dump/decode_sideband_req for QSES (Lyude)
Changes in v7:
-None
Changes in v8:
-Reverse the parsing on the hdcp_*x_device_present bits and leave
breadcrumb in case this is incorrect (Anshuman)
Changes in v8.5:
-s/DRM_DEBUG_KMS/drm_dbg_kms/ (Lyude)
---
drivers/gpu/drm/drm_dp_mst_topology.c | 150 ++++++++++++++++++
.../drm/selftests/test-drm_dp_mst_helper.c | 17 ++
include/drm/drm_dp_helper.h | 3 +
include/drm/drm_dp_mst_helper.h | 44 +++++
4 files changed, 214 insertions(+)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 67dd72ea200e..0968fc716d81 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -20,11 +20,13 @@
* OF THIS SOFTWARE.
*/
+#include <linux/bitfield.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/random.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/iopoll.h>
@@ -423,6 +425,22 @@ drm_dp_encode_sideband_req(const struct drm_dp_sideband_msg_req_body *req,
memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
idx += req->u.i2c_write.num_bytes;
break;
+ case DP_QUERY_STREAM_ENC_STATUS: {
+ const struct drm_dp_query_stream_enc_status *msg;
+
+ msg = &req->u.enc_status;
+ buf[idx] = msg->stream_id;
+ idx++;
+ memcpy(&buf[idx], msg->client_id, sizeof(msg->client_id));
+ idx += sizeof(msg->client_id);
+ buf[idx] = 0;
+ buf[idx] |= FIELD_PREP(GENMASK(1, 0), msg->stream_event);
+ buf[idx] |= msg->valid_stream_event ? BIT(2) : 0;
+ buf[idx] |= FIELD_PREP(GENMASK(4, 3), msg->stream_behavior);
+ buf[idx] |= msg->valid_stream_behavior ? BIT(5) : 0;
+ idx++;
+ }
+ break;
}
raw->cur_len = idx;
}
@@ -551,6 +569,20 @@ drm_dp_decode_sideband_req(const struct drm_dp_sideband_msg_tx *raw,
return -ENOMEM;
}
break;
+ case DP_QUERY_STREAM_ENC_STATUS:
+ req->u.enc_status.stream_id = buf[idx++];
+ for (i = 0; i < sizeof(req->u.enc_status.client_id); i++)
+ req->u.enc_status.client_id[i] = buf[idx++];
+
+ req->u.enc_status.stream_event = FIELD_GET(GENMASK(1, 0),
+ buf[idx]);
+ req->u.enc_status.valid_stream_event = FIELD_GET(BIT(2),
+ buf[idx]);
+ req->u.enc_status.stream_behavior = FIELD_GET(GENMASK(4, 3),
+ buf[idx]);
+ req->u.enc_status.valid_stream_behavior = FIELD_GET(BIT(5),
+ buf[idx]);
+ break;
}
return 0;
@@ -629,6 +661,16 @@ drm_dp_dump_sideband_msg_req_body(const struct drm_dp_sideband_msg_req_body *req
req->u.i2c_write.num_bytes, req->u.i2c_write.num_bytes,
req->u.i2c_write.bytes);
break;
+ case DP_QUERY_STREAM_ENC_STATUS:
+ P("stream_id=%u client_id=%*ph stream_event=%x "
+ "valid_event=%d stream_behavior=%x valid_behavior=%d",
+ req->u.enc_status.stream_id,
+ (int)ARRAY_SIZE(req->u.enc_status.client_id),
+ req->u.enc_status.client_id, req->u.enc_status.stream_event,
+ req->u.enc_status.valid_stream_event,
+ req->u.enc_status.stream_behavior,
+ req->u.enc_status.valid_stream_behavior);
+ break;
default:
P("???\n");
break;
@@ -936,6 +978,42 @@ static bool drm_dp_sideband_parse_power_updown_phy_ack(struct drm_dp_sideband_ms
return true;
}
+static bool
+drm_dp_sideband_parse_query_stream_enc_status(
+ struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_reply_body *repmsg)
+{
+ struct drm_dp_query_stream_enc_status_ack_reply *reply;
+
+ reply = &repmsg->u.enc_status;
+
+ reply->stream_id = raw->msg[3];
+
+ reply->reply_signed = raw->msg[2] & BIT(0);
+
+ /*
+ * NOTE: It's my impression from reading the spec that the below parsing
+ * is correct. However I noticed while testing with an HDCP 1.4 display
+ * through an HDCP 2.2 hub that only bit 3 was set. In that case, I
+ * would expect both bits to be set. So keep the parsing following the
+ * spec, but beware reality might not match the spec (at least for some
+ * configurations).
+ */
+ reply->hdcp_1x_device_present = raw->msg[2] & BIT(4);
+ reply->hdcp_2x_device_present = raw->msg[2] & BIT(3);
+
+ reply->query_capable_device_present = raw->msg[2] & BIT(5);
+ reply->legacy_device_present = raw->msg[2] & BIT(6);
+ reply->unauthorizable_device_present = raw->msg[2] & BIT(7);
+
+ reply->auth_completed = !!(raw->msg[1] & BIT(3));
+ reply->encryption_enabled = !!(raw->msg[1] & BIT(4));
+ reply->repeater_present = !!(raw->msg[1] & BIT(5));
+ reply->state = (raw->msg[1] & GENMASK(7, 6)) >> 6;
+
+ return true;
+}
+
static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
struct drm_dp_sideband_msg_reply_body *msg)
{
@@ -970,6 +1048,8 @@ static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
return drm_dp_sideband_parse_power_updown_phy_ack(raw, msg);
case DP_CLEAR_PAYLOAD_ID_TABLE:
return true; /* since there's nothing to parse */
+ case DP_QUERY_STREAM_ENC_STATUS:
+ return drm_dp_sideband_parse_query_stream_enc_status(raw, msg);
default:
DRM_ERROR("Got unknown reply 0x%02x (%s)\n", msg->req_type,
drm_dp_mst_req_type_str(msg->req_type));
@@ -1121,6 +1201,25 @@ static void build_power_updown_phy(struct drm_dp_sideband_msg_tx *msg,
msg->path_msg = true;
}
+static int
+build_query_stream_enc_status(struct drm_dp_sideband_msg_tx *msg, u8 stream_id,
+ u8 *q_id)
+{
+ struct drm_dp_sideband_msg_req_body req;
+
+ req.req_type = DP_QUERY_STREAM_ENC_STATUS;
+ req.u.enc_status.stream_id = stream_id;
+ memcpy(req.u.enc_status.client_id, q_id,
+ sizeof(req.u.enc_status.client_id));
+ req.u.enc_status.stream_event = 0;
+ req.u.enc_status.valid_stream_event = false;
+ req.u.enc_status.stream_behavior = 0;
+ req.u.enc_status.valid_stream_behavior = false;
+
+ drm_dp_encode_sideband_req(&req, msg);
+ return 0;
+}
+
static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_vcpi *vcpi)
{
@@ -3153,6 +3252,57 @@ int drm_dp_send_power_updown_phy(struct drm_dp_mst_topology_mgr *mgr,
}
EXPORT_SYMBOL(drm_dp_send_power_updown_phy);
+int drm_dp_send_query_stream_enc_status(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port,
+ struct drm_dp_query_stream_enc_status_ack_reply *status)
+{
+ struct drm_dp_sideband_msg_tx *txmsg;
+ u8 nonce[7];
+ int len, ret;
+
+ txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
+ if (!txmsg)
+ return -ENOMEM;
+
+ port = drm_dp_mst_topology_get_port_validated(mgr, port);
+ if (!port) {
+ ret = -EINVAL;
+ goto out_get_port;
+ }
+
+ get_random_bytes(nonce, sizeof(nonce));
+
+ /*
+ * "Source device targets the QUERY_STREAM_ENCRYPTION_STATUS message
+ * transaction at the MST Branch device directly connected to the
+ * Source"
+ */
+ txmsg->dst = mgr->mst_primary;
+
+ len = build_query_stream_enc_status(txmsg, port->vcpi.vcpi, nonce);
+
+ drm_dp_queue_down_tx(mgr, txmsg);
+
+ ret = drm_dp_mst_wait_tx_reply(mgr->mst_primary, txmsg);
+ if (ret < 0) {
+ goto out;
+ } else if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) {
+ drm_dbg_kms(mgr->dev, "query encryption status nak received\n");
+ ret = -ENXIO;
+ goto out;
+ }
+
+ ret = 0;
+ memcpy(status, &txmsg->reply.u.enc_status, sizeof(*status));
+
+out:
+ drm_dp_mst_topology_put_port(port);
+out_get_port:
+ kfree(txmsg);
+ return ret;
+}
+EXPORT_SYMBOL(drm_dp_send_query_stream_enc_status);
+
static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
int id,
struct drm_dp_payload *payload)
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 bd990d178765..1d696ec001cf 100644
--- a/drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c
+++ b/drivers/gpu/drm/selftests/test-drm_dp_mst_helper.c
@@ -5,6 +5,8 @@
#define PREFIX_STR "[drm_dp_mst_helper]"
+#include <linux/random.h>
+
#include <drm/drm_dp_mst_helper.h>
#include <drm/drm_print.h>
@@ -237,6 +239,21 @@ int igt_dp_mst_sideband_msg_req_decode(void *unused)
in.u.i2c_write.bytes = data;
DO_TEST();
+ in.req_type = DP_QUERY_STREAM_ENC_STATUS;
+ in.u.enc_status.stream_id = 1;
+ DO_TEST();
+ get_random_bytes(in.u.enc_status.client_id,
+ sizeof(in.u.enc_status.client_id));
+ DO_TEST();
+ in.u.enc_status.stream_event = 3;
+ DO_TEST();
+ in.u.enc_status.valid_stream_event = 0;
+ DO_TEST();
+ in.u.enc_status.stream_behavior = 3;
+ DO_TEST();
+ in.u.enc_status.valid_stream_behavior = 1;
+ DO_TEST();
+
#undef DO_TEST
return 0;
}
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index 5c2819924862..5e41e15cb5a1 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -1109,6 +1109,9 @@
#define DP_POWER_DOWN_PHY 0x25
#define DP_SINK_EVENT_NOTIFY 0x30
#define DP_QUERY_STREAM_ENC_STATUS 0x38
+#define DP_QUERY_STREAM_ENC_STATUS_STATE_NO_EXIST 0
+#define DP_QUERY_STREAM_ENC_STATUS_STATE_INACTIVE 1
+#define DP_QUERY_STREAM_ENC_STATUS_STATE_ACTIVE 2
/* DP 1.2 MST sideband reply types */
#define DP_SIDEBAND_REPLY_ACK 0x00
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index 8b9eb4db3381..371eef8798ad 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -313,6 +313,34 @@ struct drm_dp_remote_i2c_write_ack_reply {
u8 port_number;
};
+struct drm_dp_query_stream_enc_status_ack_reply {
+ /* Bit[23:16]- Stream Id */
+ u8 stream_id;
+
+ /* Bit[15]- Signed */
+ bool reply_signed;
+
+ /* Bit[10:8]- Stream Output Sink Type */
+ bool unauthorizable_device_present;
+ bool legacy_device_present;
+ bool query_capable_device_present;
+
+ /* Bit[12:11]- Stream Output CP Type */
+ bool hdcp_1x_device_present;
+ bool hdcp_2x_device_present;
+
+ /* Bit[4]- Stream Authentication */
+ bool auth_completed;
+
+ /* Bit[3]- Stream Encryption */
+ bool encryption_enabled;
+
+ /* Bit[2]- Stream Repeater Function Present */
+ bool repeater_present;
+
+ /* Bit[1:0]- Stream State */
+ u8 state;
+};
#define DRM_DP_MAX_SDP_STREAMS 16
struct drm_dp_allocate_payload {
@@ -374,6 +402,15 @@ struct drm_dp_remote_i2c_write {
u8 *bytes;
};
+struct drm_dp_query_stream_enc_status {
+ u8 stream_id;
+ u8 client_id[7]; /* 56-bit nonce */
+ u8 stream_event;
+ bool valid_stream_event;
+ u8 stream_behavior;
+ u8 valid_stream_behavior;
+};
+
/* this covers ENUM_RESOURCES, POWER_DOWN_PHY, POWER_UP_PHY */
struct drm_dp_port_number_req {
u8 port_number;
@@ -422,6 +459,8 @@ struct drm_dp_sideband_msg_req_body {
struct drm_dp_remote_i2c_read i2c_read;
struct drm_dp_remote_i2c_write i2c_write;
+
+ struct drm_dp_query_stream_enc_status enc_status;
} u;
};
@@ -444,6 +483,8 @@ struct drm_dp_sideband_msg_reply_body {
struct drm_dp_remote_i2c_read_ack_reply remote_i2c_read_ack;
struct drm_dp_remote_i2c_read_nak_reply remote_i2c_read_nack;
struct drm_dp_remote_i2c_write_ack_reply remote_i2c_write_ack;
+
+ struct drm_dp_query_stream_enc_status_ack_reply enc_status;
} u;
};
@@ -808,6 +849,9 @@ drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
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 drm_dp_send_query_stream_enc_status(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port,
+ struct drm_dp_query_stream_enc_status_ack_reply *status);
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);
--
Sean Paul, Software Engineer, Google / Chromium OS
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