Re: [PATCH v4 13/14] drm/mst: Add support for QUERY_STREAM_ENCRYPTION_STATUS MST sideband message

Hey - I've got a good bit of stuff on my plate right now since I just got back from PTO and am going through my backlog of stuff, but I'll try to get this reviewed first chance I get

On Tue, 2020-02-18 at 17:02 -0500, Sean Paul wrote:

From: Sean Paul seanpaul@chromium.org

Used to query whether an MST stream is encrypted or not.

Cc: Lyude Paul lyude@redhat.com Signed-off-by: Sean Paul seanpaul@chromium.org

Changes in v4:

-Added to the set

drivers/gpu/drm/drm_dp_mst_topology.c | 117 ++++++++++++++++++++++++++ include/drm/drm_dp_helper.h | 3 + include/drm/drm_dp_mst_helper.h | 44 ++++++++++ 3 files changed, 164 insertions(+)

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index a811247cecfef..30b6dc6ce54c2 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -25,6 +25,7 @@ #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>

@@ -418,6 +419,22 @@ 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] |= msg->stream_event & GENMASK(1, 0);
  

• buf[idx] |= msg->valid_stream_event ? BIT(2) : 0;
  

• buf[idx] |= (msg->stream_behavior & GENMASK(1, 0)) << 3;
  

• buf[idx] |= msg->valid_stream_behavior ? BIT(5) : 0;
  

• idx++;
  

• }
  

• break;
  

  } raw->cur_len = idx;

} @@ -926,6 +943,34 @@ 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);
• reply->hdcp_1x_device_present = raw->msg[2] & BIT(3);
• reply->hdcp_2x_device_present = raw->msg[2] & BIT(4);
• 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) { @@ -960,6 +1005,8 @@ 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)); @@ -1113,6 +1160,25 @@ static int build_power_updown_phy(struct drm_dp_sideband_msg_tx *msg, return 0; }

+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) { @@ -3154,6 +3220,57 @@ 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_DEBUG_KMS("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/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index b8f6bac6341c1..11b2c49e4f0f4 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -1099,6 +1099,9 @@ #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 5483f888712ad..baf3405df44d8 100644 --- a/include/drm/drm_dp_mst_helper.h +++ b/include/drm/drm_dp_mst_helper.h @@ -305,6 +305,34 @@ 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;

+};

struct drm_dp_sideband_msg_rx { u8 chunk[48]; @@ -378,6 +406,15 @@ 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; @@ -426,6 +463,8 @@ 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;

};

@@ -448,6 +487,8 @@ 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;

};

@@ -804,6 +845,9 @@ 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);