--- /dev/null
+/*
+ * Copyright © 2014 Red Hat
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission. The copyright holders make no representations
+ * about the suitability of this software for any purpose. It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/i2c.h>
+#include <drm/drm_dp_mst_helper.h>
+#include <drm/drmP.h>
+
+#include <drm/drm_fixed.h>
+
+/**
+ * DOC: dp mst helper
+ *
+ * These functions contain parts of the DisplayPort 1.2a MultiStream Transport
+ * protocol. The helpers contain a topology manager and bandwidth manager.
+ * The helpers encapsulate the sending and received of sideband msgs.
+ */
+static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
+ char *buf);
+static int test_calc_pbn_mode(void);
+
+static void drm_dp_put_port(struct drm_dp_mst_port *port);
+
+static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
+ int id,
+ struct drm_dp_payload *payload);
+
+static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port,
+ int offset, int size, u8 *bytes);
+
+static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_branch *mstb);
+static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_branch *mstb,
+ struct drm_dp_mst_port *port);
+static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
+ u8 *guid);
+
+static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux);
+static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux);
+static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
+/* sideband msg handling */
+static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)
+{
+ u8 bitmask = 0x80;
+ u8 bitshift = 7;
+ u8 array_index = 0;
+ int number_of_bits = num_nibbles * 4;
+ u8 remainder = 0;
+
+ while (number_of_bits != 0) {
+ number_of_bits--;
+ remainder <<= 1;
+ remainder |= (data[array_index] & bitmask) >> bitshift;
+ bitmask >>= 1;
+ bitshift--;
+ if (bitmask == 0) {
+ bitmask = 0x80;
+ bitshift = 7;
+ array_index++;
+ }
+ if ((remainder & 0x10) == 0x10)
+ remainder ^= 0x13;
+ }
+
+ number_of_bits = 4;
+ while (number_of_bits != 0) {
+ number_of_bits--;
+ remainder <<= 1;
+ if ((remainder & 0x10) != 0)
+ remainder ^= 0x13;
+ }
+
+ return remainder;
+}
+
+static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
+{
+ u8 bitmask = 0x80;
+ u8 bitshift = 7;
+ u8 array_index = 0;
+ int number_of_bits = number_of_bytes * 8;
+ u16 remainder = 0;
+
+ while (number_of_bits != 0) {
+ number_of_bits--;
+ remainder <<= 1;
+ remainder |= (data[array_index] & bitmask) >> bitshift;
+ bitmask >>= 1;
+ bitshift--;
+ if (bitmask == 0) {
+ bitmask = 0x80;
+ bitshift = 7;
+ array_index++;
+ }
+ if ((remainder & 0x100) == 0x100)
+ remainder ^= 0xd5;
+ }
+
+ number_of_bits = 8;
+ while (number_of_bits != 0) {
+ number_of_bits--;
+ remainder <<= 1;
+ if ((remainder & 0x100) != 0)
+ remainder ^= 0xd5;
+ }
+
+ return remainder & 0xff;
+}
+static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
+{
+ u8 size = 3;
+ size += (hdr->lct / 2);
+ return size;
+}
+
+static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
+ u8 *buf, int *len)
+{
+ int idx = 0;
+ int i;
+ u8 crc4;
+ buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf);
+ for (i = 0; i < (hdr->lct / 2); i++)
+ buf[idx++] = hdr->rad[i];
+ buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) |
+ (hdr->msg_len & 0x3f);
+ buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4);
+
+ crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
+ buf[idx - 1] |= (crc4 & 0xf);
+
+ *len = idx;
+}
+
+static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
+ u8 *buf, int buflen, u8 *hdrlen)
+{
+ u8 crc4;
+ u8 len;
+ int i;
+ u8 idx;
+ if (buf[0] == 0)
+ return false;
+ len = 3;
+ len += ((buf[0] & 0xf0) >> 4) / 2;
+ if (len > buflen)
+ return false;
+ crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
+
+ if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
+ DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
+ return false;
+ }
+
+ hdr->lct = (buf[0] & 0xf0) >> 4;
+ hdr->lcr = (buf[0] & 0xf);
+ idx = 1;
+ for (i = 0; i < (hdr->lct / 2); i++)
+ hdr->rad[i] = buf[idx++];
+ hdr->broadcast = (buf[idx] >> 7) & 0x1;
+ hdr->path_msg = (buf[idx] >> 6) & 0x1;
+ hdr->msg_len = buf[idx] & 0x3f;
+ idx++;
+ hdr->somt = (buf[idx] >> 7) & 0x1;
+ hdr->eomt = (buf[idx] >> 6) & 0x1;
+ hdr->seqno = (buf[idx] >> 4) & 0x1;
+ idx++;
+ *hdrlen = idx;
+ return true;
+}
+
+static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_tx *raw)
+{
+ int idx = 0;
+ int i;
+ u8 *buf = raw->msg;
+ buf[idx++] = req->req_type & 0x7f;
+
+ switch (req->req_type) {
+ case DP_ENUM_PATH_RESOURCES:
+ buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
+ idx++;
+ break;
+ case DP_ALLOCATE_PAYLOAD:
+ buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 |
+ (req->u.allocate_payload.number_sdp_streams & 0xf);
+ idx++;
+ buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
+ idx++;
+ buf[idx] = (req->u.allocate_payload.pbn >> 8);
+ idx++;
+ buf[idx] = (req->u.allocate_payload.pbn & 0xff);
+ idx++;
+ for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {
+ buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) |
+ (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);
+ idx++;
+ }
+ if (req->u.allocate_payload.number_sdp_streams & 1) {
+ i = req->u.allocate_payload.number_sdp_streams - 1;
+ buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;
+ idx++;
+ }
+ break;
+ case DP_QUERY_PAYLOAD:
+ buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
+ idx++;
+ buf[idx] = (req->u.query_payload.vcpi & 0x7f);
+ idx++;
+ break;
+ case DP_REMOTE_DPCD_READ:
+ buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;
+ buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;
+ idx++;
+ buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
+ idx++;
+ buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
+ idx++;
+ buf[idx] = (req->u.dpcd_read.num_bytes);
+ idx++;
+ break;
+
+ case DP_REMOTE_DPCD_WRITE:
+ buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;
+ buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;
+ idx++;
+ buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
+ idx++;
+ buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
+ idx++;
+ buf[idx] = (req->u.dpcd_write.num_bytes);
+ idx++;
+ memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
+ idx += req->u.dpcd_write.num_bytes;
+ break;
+ case DP_REMOTE_I2C_READ:
+ buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;
+ buf[idx] |= (req->u.i2c_read.num_transactions & 0x3);
+ idx++;
+ for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {
+ buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;
+ idx++;
+ buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
+ idx++;
+ memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
+ idx += req->u.i2c_read.transactions[i].num_bytes;
+
+ buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;
+ buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
+ idx++;
+ }
+ buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
+ idx++;
+ buf[idx] = (req->u.i2c_read.num_bytes_read);
+ idx++;
+ break;
+
+ case DP_REMOTE_I2C_WRITE:
+ buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
+ idx++;
+ buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
+ idx++;
+ buf[idx] = (req->u.i2c_write.num_bytes);
+ idx++;
+ memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
+ idx += req->u.i2c_write.num_bytes;
+ break;
+ }
+ raw->cur_len = idx;
+}
+
+static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
+{
+ u8 crc4;
+ crc4 = drm_dp_msg_data_crc4(msg, len);
+ msg[len] = crc4;
+}
+
+static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
+ struct drm_dp_sideband_msg_tx *raw)
+{
+ int idx = 0;
+ u8 *buf = raw->msg;
+
+ buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
+
+ raw->cur_len = idx;
+}
+
+/* this adds a chunk of msg to the builder to get the final msg */
+static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
+ u8 *replybuf, u8 replybuflen, bool hdr)
+{
+ int ret;
+ u8 crc4;
+
+ if (hdr) {
+ u8 hdrlen;
+ struct drm_dp_sideband_msg_hdr recv_hdr;
+ ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);
+ if (ret == false) {
+ print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);
+ return false;
+ }
+
+ /* get length contained in this portion */
+ msg->curchunk_len = recv_hdr.msg_len;
+ msg->curchunk_hdrlen = hdrlen;
+
+ /* we have already gotten an somt - don't bother parsing */
+ if (recv_hdr.somt && msg->have_somt)
+ return false;
+
+ if (recv_hdr.somt) {
+ memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));
+ msg->have_somt = true;
+ }
+ if (recv_hdr.eomt)
+ msg->have_eomt = true;
+
+ /* copy the bytes for the remainder of this header chunk */
+ msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen));
+ memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx);
+ } else {
+ memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
+ msg->curchunk_idx += replybuflen;
+ }
+
+ if (msg->curchunk_idx >= msg->curchunk_len) {
+ /* do CRC */
+ crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
+ /* copy chunk into bigger msg */
+ memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
+ msg->curlen += msg->curchunk_len - 1;
+ }
+ return true;
+}
+
+static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_reply_body *repmsg)
+{
+ int idx = 1;
+ int i;
+ memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
+ idx += 16;
+ repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ for (i = 0; i < repmsg->u.link_addr.nports; i++) {
+ if (raw->msg[idx] & 0x80)
+ repmsg->u.link_addr.ports[i].input_port = 1;
+
+ repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;
+ repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);
+
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;
+ repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;
+ if (repmsg->u.link_addr.ports[i].input_port == 0)
+ repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ if (repmsg->u.link_addr.ports[i].input_port == 0) {
+ repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
+ idx += 16;
+ if (idx > raw->curlen)
+ goto fail_len;
+ repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;
+ repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);
+ idx++;
+
+ }
+ if (idx > raw->curlen)
+ goto fail_len;
+ }
+
+ return true;
+fail_len:
+ DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
+ return false;
+}
+
+static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_reply_body *repmsg)
+{
+ int idx = 1;
+ repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
+ if (idx > raw->curlen)
+ goto fail_len;
+
+ memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
+ return true;
+fail_len:
+ DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
+ return false;
+}
+
+static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_reply_body *repmsg)
+{
+ int idx = 1;
+ repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ return true;
+fail_len:
+ DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
+ return false;
+}
+
+static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_reply_body *repmsg)
+{
+ int idx = 1;
+
+ repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
+ idx++;
+ /* TODO check */
+ memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
+ return true;
+fail_len:
+ DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
+ return false;
+}
+
+static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_reply_body *repmsg)
+{
+ int idx = 1;
+ repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
+ idx += 2;
+ if (idx > raw->curlen)
+ goto fail_len;
+ repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
+ idx += 2;
+ if (idx > raw->curlen)
+ goto fail_len;
+ return true;
+fail_len:
+ DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
+ return false;
+}
+
+static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_reply_body *repmsg)
+{
+ int idx = 1;
+ repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ repmsg->u.allocate_payload.vcpi = raw->msg[idx];
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
+ idx += 2;
+ if (idx > raw->curlen)
+ goto fail_len;
+ return true;
+fail_len:
+ DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen);
+ return false;
+}
+
+static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_reply_body *repmsg)
+{
+ int idx = 1;
+ repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+ repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
+ idx += 2;
+ if (idx > raw->curlen)
+ goto fail_len;
+ return true;
+fail_len:
+ DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen);
+ return false;
+}
+
+static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_reply_body *msg)
+{
+ memset(msg, 0, sizeof(*msg));
+ msg->reply_type = (raw->msg[0] & 0x80) >> 7;
+ msg->req_type = (raw->msg[0] & 0x7f);
+
+ if (msg->reply_type) {
+ memcpy(msg->u.nak.guid, &raw->msg[1], 16);
+ msg->u.nak.reason = raw->msg[17];
+ msg->u.nak.nak_data = raw->msg[18];
+ return false;
+ }
+
+ switch (msg->req_type) {
+ case DP_LINK_ADDRESS:
+ return drm_dp_sideband_parse_link_address(raw, msg);
+ case DP_QUERY_PAYLOAD:
+ return drm_dp_sideband_parse_query_payload_ack(raw, msg);
+ case DP_REMOTE_DPCD_READ:
+ return drm_dp_sideband_parse_remote_dpcd_read(raw, msg);
+ case DP_REMOTE_DPCD_WRITE:
+ return drm_dp_sideband_parse_remote_dpcd_write(raw, msg);
+ case DP_REMOTE_I2C_READ:
+ return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg);
+ case DP_ENUM_PATH_RESOURCES:
+ return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg);
+ case DP_ALLOCATE_PAYLOAD:
+ return drm_dp_sideband_parse_allocate_payload_ack(raw, msg);
+ default:
+ DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type);
+ return false;
+ }
+}
+
+static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_req_body *msg)
+{
+ int idx = 1;
+
+ msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+
+ memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16);
+ idx += 16;
+ if (idx > raw->curlen)
+ goto fail_len;
+
+ msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1;
+ msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
+ msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1;
+ msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1;
+ msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7);
+ idx++;
+ return true;
+fail_len:
+ DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen);
+ return false;
+}
+
+static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw,
+ struct drm_dp_sideband_msg_req_body *msg)
+{
+ int idx = 1;
+
+ msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
+ idx++;
+ if (idx > raw->curlen)
+ goto fail_len;
+
+ memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16);
+ idx += 16;
+ if (idx > raw->curlen)
+ goto fail_len;
+
+ msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
+ idx++;
+ return true;
+fail_len:
+ DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen);
+ return false;
+}
+
+static bool drm_dp_sideband_parse_req(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);
+
+ switch (msg->req_type) {
+ case DP_CONNECTION_STATUS_NOTIFY:
+ return drm_dp_sideband_parse_connection_status_notify(raw, msg);
+ case DP_RESOURCE_STATUS_NOTIFY:
+ return drm_dp_sideband_parse_resource_status_notify(raw, msg);
+ default:
+ DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type);
+ return false;
+ }
+}
+
+static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
+{
+ struct drm_dp_sideband_msg_req_body req;
+
+ req.req_type = DP_REMOTE_DPCD_WRITE;
+ req.u.dpcd_write.port_number = port_num;
+ req.u.dpcd_write.dpcd_address = offset;
+ req.u.dpcd_write.num_bytes = num_bytes;
+ req.u.dpcd_write.bytes = bytes;
+ drm_dp_encode_sideband_req(&req, msg);
+
+ return 0;
+}
+
+static int build_link_address(struct drm_dp_sideband_msg_tx *msg)
+{
+ struct drm_dp_sideband_msg_req_body req;
+
+ req.req_type = DP_LINK_ADDRESS;
+ drm_dp_encode_sideband_req(&req, msg);
+ return 0;
+}
+
+static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num)
+{
+ struct drm_dp_sideband_msg_req_body req;
+
+ req.req_type = DP_ENUM_PATH_RESOURCES;
+ req.u.port_num.port_number = port_num;
+ drm_dp_encode_sideband_req(&req, msg);
+ msg->path_msg = true;
+ return 0;
+}
+
+static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
+ u8 vcpi, uint16_t pbn)
+{
+ struct drm_dp_sideband_msg_req_body req;
+ memset(&req, 0, sizeof(req));
+ req.req_type = DP_ALLOCATE_PAYLOAD;
+ req.u.allocate_payload.port_number = port_num;
+ req.u.allocate_payload.vcpi = vcpi;
+ req.u.allocate_payload.pbn = pbn;
+ drm_dp_encode_sideband_req(&req, msg);
+ msg->path_msg = true;
+ return 0;
+}
+
+static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_vcpi *vcpi)
+{
+ int ret, vcpi_ret;
+
+ mutex_lock(&mgr->payload_lock);
+ ret = find_first_zero_bit(&mgr->payload_mask, mgr->max_payloads + 1);
+ if (ret > mgr->max_payloads) {
+ ret = -EINVAL;
+ DRM_DEBUG_KMS("out of payload ids %d\n", ret);
+ goto out_unlock;
+ }
+
+ vcpi_ret = find_first_zero_bit(&mgr->vcpi_mask, mgr->max_payloads + 1);
+ if (vcpi_ret > mgr->max_payloads) {
+ ret = -EINVAL;
+ DRM_DEBUG_KMS("out of vcpi ids %d\n", ret);
+ goto out_unlock;
+ }
+
+ set_bit(ret, &mgr->payload_mask);
+ set_bit(vcpi_ret, &mgr->vcpi_mask);
+ vcpi->vcpi = vcpi_ret + 1;
+ mgr->proposed_vcpis[ret - 1] = vcpi;
+out_unlock:
+ mutex_unlock(&mgr->payload_lock);
+ return ret;
+}
+
+static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
+ int vcpi)
+{
+ int i;
+ if (vcpi == 0)
+ return;
+
+ mutex_lock(&mgr->payload_lock);
+ DRM_DEBUG_KMS("putting payload %d\n", vcpi);
+ clear_bit(vcpi - 1, &mgr->vcpi_mask);
+
+ for (i = 0; i < mgr->max_payloads; i++) {
+ if (mgr->proposed_vcpis[i])
+ if (mgr->proposed_vcpis[i]->vcpi == vcpi) {
+ mgr->proposed_vcpis[i] = NULL;
+ clear_bit(i + 1, &mgr->payload_mask);
+ }
+ }
+ mutex_unlock(&mgr->payload_lock);
+}
+
+static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_sideband_msg_tx *txmsg)
+{
+ bool ret;
+
+ /*
+ * All updates to txmsg->state are protected by mgr->qlock, and the two
+ * cases we check here are terminal states. For those the barriers
+ * provided by the wake_up/wait_event pair are enough.
+ */
+ ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX ||
+ txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT);
+ return ret;
+}
+
+static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
+ struct drm_dp_sideband_msg_tx *txmsg)
+{
+ struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
+ int ret;
+
+ ret = wait_event_timeout(mgr->tx_waitq,
+ check_txmsg_state(mgr, txmsg),
+ (4 * HZ));
+ mutex_lock(&mstb->mgr->qlock);
+ if (ret > 0) {
+ if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
+ ret = -EIO;
+ goto out;
+ }
+ } else {
+ DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
+
+ /* dump some state */
+ ret = -EIO;
+
+ /* remove from q */
+ if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
+ txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
+ list_del(&txmsg->next);
+ }
+
+ if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
+ txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
+ mstb->tx_slots[txmsg->seqno] = NULL;
+ }
+ }
+out:
+ mutex_unlock(&mgr->qlock);
+
+ return ret;
+}
+
+static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
+{
+ struct drm_dp_mst_branch *mstb;
+
+ mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
+ if (!mstb)
+ return NULL;
+
+ mstb->lct = lct;
+ if (lct > 1)
+ memcpy(mstb->rad, rad, lct / 2);
+ INIT_LIST_HEAD(&mstb->ports);
+ kref_init(&mstb->kref);
+ return mstb;
+}
+
+static void drm_dp_destroy_mst_branch_device(struct kref *kref)
+{
+ struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
+ struct drm_dp_mst_port *port, *tmp;
+ bool wake_tx = false;
+
+ cancel_work_sync(&mstb->mgr->work);
+
+ /*
+ * destroy all ports - don't need lock
+ * as there are no more references to the mst branch
+ * device at this point.
+ */
+ list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
+ list_del(&port->next);
+ drm_dp_put_port(port);
+ }
+
+ /* drop any tx slots msg */
+ mutex_lock(&mstb->mgr->qlock);
+ if (mstb->tx_slots[0]) {
+ mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
+ mstb->tx_slots[0] = NULL;
+ wake_tx = true;
+ }
+ if (mstb->tx_slots[1]) {
+ mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
+ mstb->tx_slots[1] = NULL;
+ wake_tx = true;
+ }
+ mutex_unlock(&mstb->mgr->qlock);
+
+ if (wake_tx)
+ wake_up(&mstb->mgr->tx_waitq);
+ kfree(mstb);
+}
+
+static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
+{
+ kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
+}
+
+
+static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
+{
+ struct drm_dp_mst_branch *mstb;
+
+ switch (old_pdt) {
+ case DP_PEER_DEVICE_DP_LEGACY_CONV:
+ case DP_PEER_DEVICE_SST_SINK:
+ /* remove i2c over sideband */
+ drm_dp_mst_unregister_i2c_bus(&port->aux);
+ break;
+ case DP_PEER_DEVICE_MST_BRANCHING:
+ mstb = port->mstb;
+ port->mstb = NULL;
+ drm_dp_put_mst_branch_device(mstb);
+ break;
+ }
+}
+
+static void drm_dp_destroy_port(struct kref *kref)
+{
+ struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
+ struct drm_dp_mst_topology_mgr *mgr = port->mgr;
+ if (!port->input) {
+ port->vcpi.num_slots = 0;
+
+ kfree(port->cached_edid);
+ if (port->connector)
+ (*port->mgr->cbs->destroy_connector)(mgr, port->connector);
+ drm_dp_port_teardown_pdt(port, port->pdt);
+
+ if (!port->input && port->vcpi.vcpi > 0)
+ drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
+ }
+ kfree(port);
+
+ (*mgr->cbs->hotplug)(mgr);
+}
+
+static void drm_dp_put_port(struct drm_dp_mst_port *port)
+{
+ kref_put(&port->kref, drm_dp_destroy_port);
+}
+
+static struct drm_dp_mst_branch *drm_dp_mst_get_validated_mstb_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_branch *to_find)
+{
+ struct drm_dp_mst_port *port;
+ struct drm_dp_mst_branch *rmstb;
+ if (to_find == mstb) {
+ kref_get(&mstb->kref);
+ return mstb;
+ }
+ list_for_each_entry(port, &mstb->ports, next) {
+ if (port->mstb) {
+ rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
+ if (rmstb)
+ return rmstb;
+ }
+ }
+ return NULL;
+}
+
+static struct drm_dp_mst_branch *drm_dp_get_validated_mstb_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb)
+{
+ struct drm_dp_mst_branch *rmstb = NULL;
+ mutex_lock(&mgr->lock);
+ if (mgr->mst_primary)
+ rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
+ mutex_unlock(&mgr->lock);
+ return rmstb;
+}
+
+static struct drm_dp_mst_port *drm_dp_mst_get_port_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *to_find)
+{
+ struct drm_dp_mst_port *port, *mport;
+
+ list_for_each_entry(port, &mstb->ports, next) {
+ if (port == to_find) {
+ kref_get(&port->kref);
+ return port;
+ }
+ if (port->mstb) {
+ mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
+ if (mport)
+ return mport;
+ }
+ }
+ return NULL;
+}
+
+static struct drm_dp_mst_port *drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
+{
+ struct drm_dp_mst_port *rport = NULL;
+ mutex_lock(&mgr->lock);
+ if (mgr->mst_primary)
+ rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
+ mutex_unlock(&mgr->lock);
+ return rport;
+}
+
+static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
+{
+ struct drm_dp_mst_port *port;
+
+ list_for_each_entry(port, &mstb->ports, next) {
+ if (port->port_num == port_num) {
+ kref_get(&port->kref);
+ return port;
+ }
+ }
+
+ return NULL;
+}
+
+/*
+ * calculate a new RAD for this MST branch device
+ * if parent has an LCT of 2 then it has 1 nibble of RAD,
+ * if parent has an LCT of 3 then it has 2 nibbles of RAD,
+ */
+static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
+ u8 *rad)
+{
+ int lct = port->parent->lct;
+ int shift = 4;
+ int idx = lct / 2;
+ if (lct > 1) {
+ memcpy(rad, port->parent->rad, idx);
+ shift = (lct % 2) ? 4 : 0;
+ } else
+ rad[0] = 0;
+
+ rad[idx] |= port->port_num << shift;
+ return lct + 1;
+}
+
+/*
+ * return sends link address for new mstb
+ */
+static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
+{
+ int ret;
+ u8 rad[6], lct;
+ bool send_link = false;
+ switch (port->pdt) {
+ case DP_PEER_DEVICE_DP_LEGACY_CONV:
+ case DP_PEER_DEVICE_SST_SINK:
+ /* add i2c over sideband */
+ ret = drm_dp_mst_register_i2c_bus(&port->aux);
+ break;
+ case DP_PEER_DEVICE_MST_BRANCHING:
+ lct = drm_dp_calculate_rad(port, rad);
+
+ port->mstb = drm_dp_add_mst_branch_device(lct, rad);
+ port->mstb->mgr = port->mgr;
+ port->mstb->port_parent = port;
+
+ send_link = true;
+ break;
+ }
+ return send_link;
+}
+
+static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb,
+ struct drm_dp_mst_port *port)
+{
+ int ret;
+ if (port->dpcd_rev >= 0x12) {
+ port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid);
+ if (!port->guid_valid) {
+ ret = drm_dp_send_dpcd_write(mstb->mgr,
+ port,
+ DP_GUID,
+ 16, port->guid);
+ port->guid_valid = true;
+ }
+ }
+}
+
+static void build_mst_prop_path(struct drm_dp_mst_port *port,
+ struct drm_dp_mst_branch *mstb,
+ char *proppath,
+ size_t proppath_size)
+{
+ int i;
+ char temp[8];
+ snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
+ for (i = 0; i < (mstb->lct - 1); i++) {
+ int shift = (i % 2) ? 0 : 4;
+ int port_num = mstb->rad[i / 2] >> shift;
+ snprintf(temp, sizeof(temp), "-%d", port_num);
+ strlcat(proppath, temp, proppath_size);
+ }
+ snprintf(temp, sizeof(temp), "-%d", port->port_num);
+ strlcat(proppath, temp, proppath_size);
+}
+
+static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
+ struct device *dev,
+ struct drm_dp_link_addr_reply_port *port_msg)
+{
+ struct drm_dp_mst_port *port;
+ bool ret;
+ bool created = false;
+ int old_pdt = 0;
+ int old_ddps = 0;
+ port = drm_dp_get_port(mstb, port_msg->port_number);
+ if (!port) {
+ port = kzalloc(sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return;
+ kref_init(&port->kref);
+ port->parent = mstb;
+ port->port_num = port_msg->port_number;
+ port->mgr = mstb->mgr;
+ port->aux.name = "DPMST";
+ port->aux.dev = dev;
+ created = true;
+ } else {
+ old_pdt = port->pdt;
+ old_ddps = port->ddps;
+ }
+
+ port->pdt = port_msg->peer_device_type;
+ port->input = port_msg->input_port;
+ port->mcs = port_msg->mcs;
+ port->ddps = port_msg->ddps;
+ port->ldps = port_msg->legacy_device_plug_status;
+ port->dpcd_rev = port_msg->dpcd_revision;
+ port->num_sdp_streams = port_msg->num_sdp_streams;
+ port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
+ memcpy(port->guid, port_msg->peer_guid, 16);
+
+ /* manage mstb port lists with mgr lock - take a reference
+ for this list */
+ if (created) {
+ mutex_lock(&mstb->mgr->lock);
+ kref_get(&port->kref);
+ list_add(&port->next, &mstb->ports);
+ mutex_unlock(&mstb->mgr->lock);
+ }
+
+ if (old_ddps != port->ddps) {
+ if (port->ddps) {
+ drm_dp_check_port_guid(mstb, port);
+ if (!port->input)
+ drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
+ } else {
+ port->guid_valid = false;
+ port->available_pbn = 0;
+ }
+ }
+
+ if (old_pdt != port->pdt && !port->input) {
+ drm_dp_port_teardown_pdt(port, old_pdt);
+
+ ret = drm_dp_port_setup_pdt(port);
+ if (ret == true) {
+ drm_dp_send_link_address(mstb->mgr, port->mstb);
+ port->mstb->link_address_sent = true;
+ }
+ }
+
+ if (created && !port->input) {
+ char proppath[255];
+ build_mst_prop_path(port, mstb, proppath, sizeof(proppath));
+ port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
+
+ if (port->port_num >= 8) {
+ port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc);
+ }
+ }
+
+ /* put reference to this port */
+ drm_dp_put_port(port);
+}
+
+static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
+ struct drm_dp_connection_status_notify *conn_stat)
+{
+ struct drm_dp_mst_port *port;
+ int old_pdt;
+ int old_ddps;
+ bool dowork = false;
+ port = drm_dp_get_port(mstb, conn_stat->port_number);
+ if (!port)
+ return;
+
+ old_ddps = port->ddps;
+ old_pdt = port->pdt;
+ port->pdt = conn_stat->peer_device_type;
+ port->mcs = conn_stat->message_capability_status;
+ port->ldps = conn_stat->legacy_device_plug_status;
+ port->ddps = conn_stat->displayport_device_plug_status;
+
+ if (old_ddps != port->ddps) {
+ if (port->ddps) {
+ drm_dp_check_port_guid(mstb, port);
+ dowork = true;
+ } else {
+ port->guid_valid = false;
+ port->available_pbn = 0;
+ }
+ }
+ if (old_pdt != port->pdt && !port->input) {
+ drm_dp_port_teardown_pdt(port, old_pdt);
+
+ if (drm_dp_port_setup_pdt(port))
+ dowork = true;
+ }
+
+ drm_dp_put_port(port);
+ if (dowork)
+ queue_work(system_long_wq, &mstb->mgr->work);
+
+}
+
+static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
+ u8 lct, u8 *rad)
+{
+ struct drm_dp_mst_branch *mstb;
+ struct drm_dp_mst_port *port;
+ int i;
+ /* find the port by iterating down */
+ mstb = mgr->mst_primary;
+
+ for (i = 0; i < lct - 1; i++) {
+ int shift = (i % 2) ? 0 : 4;
+ int port_num = rad[i / 2] >> shift;
+
+ list_for_each_entry(port, &mstb->ports, next) {
+ if (port->port_num == port_num) {
+ if (!port->mstb) {
+ DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
+ return NULL;
+ }
+
+ mstb = port->mstb;
+ break;
+ }
+ }
+ }
+ kref_get(&mstb->kref);
+ return mstb;
+}
+
+static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_branch *mstb)
+{
+ struct drm_dp_mst_port *port;
+
+ if (!mstb->link_address_sent) {
+ drm_dp_send_link_address(mgr, mstb);
+ mstb->link_address_sent = true;
+ }
+ list_for_each_entry(port, &mstb->ports, next) {
+ if (port->input)
+ continue;
+
+ if (!port->ddps)
+ continue;
+
+ if (!port->available_pbn)
+ drm_dp_send_enum_path_resources(mgr, mstb, port);
+
+ if (port->mstb)
+ drm_dp_check_and_send_link_address(mgr, port->mstb);
+ }
+}
+
+static void drm_dp_mst_link_probe_work(struct work_struct *work)
+{
+ struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
+
+ drm_dp_check_and_send_link_address(mgr, mgr->mst_primary);
+
+}
+
+static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
+ u8 *guid)
+{
+ static u8 zero_guid[16];
+
+ if (!memcmp(guid, zero_guid, 16)) {
+ u64 salt = get_jiffies_64();
+ memcpy(&guid[0], &salt, sizeof(u64));
+ memcpy(&guid[8], &salt, sizeof(u64));
+ return false;
+ }
+ return true;
+}
+
+#if 0
+static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
+{
+ struct drm_dp_sideband_msg_req_body req;
+
+ req.req_type = DP_REMOTE_DPCD_READ;
+ req.u.dpcd_read.port_number = port_num;
+ req.u.dpcd_read.dpcd_address = offset;
+ req.u.dpcd_read.num_bytes = num_bytes;
+ drm_dp_encode_sideband_req(&req, msg);
+
+ return 0;
+}
+#endif
+
+static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
+ bool up, u8 *msg, int len)
+{
+ int ret;
+ int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
+ int tosend, total, offset;
+ int retries = 0;
+
+retry:
+ total = len;
+ offset = 0;
+ do {
+ tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
+
+ ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
+ &msg[offset],
+ tosend);
+ if (ret != tosend) {
+ if (ret == -EIO && retries < 5) {
+ retries++;
+ goto retry;
+ }
+ DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
+ WARN(1, "fail\n");
+
+ return -EIO;
+ }
+ offset += tosend;
+ total -= tosend;
+ } while (total > 0);
+ return 0;
+}
+
+static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
+ struct drm_dp_sideband_msg_tx *txmsg)
+{
+ struct drm_dp_mst_branch *mstb = txmsg->dst;
+
+ /* both msg slots are full */
+ if (txmsg->seqno == -1) {
+ if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
+ DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
+ return -EAGAIN;
+ }
+ if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
+ txmsg->seqno = mstb->last_seqno;
+ mstb->last_seqno ^= 1;
+ } else if (mstb->tx_slots[0] == NULL)
+ txmsg->seqno = 0;
+ else
+ txmsg->seqno = 1;
+ mstb->tx_slots[txmsg->seqno] = txmsg;
+ }
+ hdr->broadcast = 0;
+ hdr->path_msg = txmsg->path_msg;
+ hdr->lct = mstb->lct;
+ hdr->lcr = mstb->lct - 1;
+ if (mstb->lct > 1)
+ memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
+ hdr->seqno = txmsg->seqno;
+ return 0;
+}
+/*
+ * process a single block of the next message in the sideband queue
+ */
+static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_sideband_msg_tx *txmsg,
+ bool up)
+{
+ u8 chunk[48];
+ struct drm_dp_sideband_msg_hdr hdr;
+ int len, space, idx, tosend;
+ int ret;
+
+ memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
+
+ if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
+ txmsg->seqno = -1;
+ txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
+ }
+
+ /* make hdr from dst mst - for replies use seqno
+ otherwise assign one */
+ ret = set_hdr_from_dst_qlock(&hdr, txmsg);
+ if (ret < 0)
+ return ret;
+
+ /* amount left to send in this message */
+ len = txmsg->cur_len - txmsg->cur_offset;
+
+ /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
+ space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
+
+ tosend = min(len, space);
+ if (len == txmsg->cur_len)
+ hdr.somt = 1;
+ if (space >= len)
+ hdr.eomt = 1;
+
+
+ hdr.msg_len = tosend + 1;
+ drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
+ memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
+ /* add crc at end */
+ drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
+ idx += tosend + 1;
+
+ ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
+ if (ret) {
+ DRM_DEBUG_KMS("sideband msg failed to send\n");
+ return ret;
+ }
+
+ txmsg->cur_offset += tosend;
+ if (txmsg->cur_offset == txmsg->cur_len) {
+ txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
+ return 1;
+ }
+ return 0;
+}
+
+static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
+{
+ struct drm_dp_sideband_msg_tx *txmsg;
+ int ret;
+
+ WARN_ON(!mutex_is_locked(&mgr->qlock));
+
+ /* construct a chunk from the first msg in the tx_msg queue */
+ if (list_empty(&mgr->tx_msg_downq)) {
+ mgr->tx_down_in_progress = false;
+ return;
+ }
+ mgr->tx_down_in_progress = true;
+
+ txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
+ ret = process_single_tx_qlock(mgr, txmsg, false);
+ if (ret == 1) {
+ /* txmsg is sent it should be in the slots now */
+ list_del(&txmsg->next);
+ } else if (ret) {
+ DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
+ list_del(&txmsg->next);
+ if (txmsg->seqno != -1)
+ txmsg->dst->tx_slots[txmsg->seqno] = NULL;
+ txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
+ wake_up(&mgr->tx_waitq);
+ }
+ if (list_empty(&mgr->tx_msg_downq)) {
+ mgr->tx_down_in_progress = false;
+ return;
+ }
+}
+
+/* called holding qlock */
+static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
+{
+ struct drm_dp_sideband_msg_tx *txmsg;
+ int ret;
+
+ /* construct a chunk from the first msg in the tx_msg queue */
+ if (list_empty(&mgr->tx_msg_upq)) {
+ mgr->tx_up_in_progress = false;
+ return;
+ }
+
+ txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next);
+ ret = process_single_tx_qlock(mgr, txmsg, true);
+ if (ret == 1) {
+ /* up txmsgs aren't put in slots - so free after we send it */
+ list_del(&txmsg->next);
+ kfree(txmsg);
+ } else if (ret)
+ DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
+ mgr->tx_up_in_progress = true;
+}
+
+static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_sideband_msg_tx *txmsg)
+{
+ mutex_lock(&mgr->qlock);
+ list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
+ if (!mgr->tx_down_in_progress)
+ process_single_down_tx_qlock(mgr);
+ mutex_unlock(&mgr->qlock);
+}
+
+static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_branch *mstb)
+{
+ int len;
+ struct drm_dp_sideband_msg_tx *txmsg;
+ int ret;
+
+ txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
+ if (!txmsg)
+ return -ENOMEM;
+
+ txmsg->dst = mstb;
+ len = build_link_address(txmsg);
+
+ drm_dp_queue_down_tx(mgr, txmsg);
+
+ ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
+ if (ret > 0) {
+ int i;
+
+ if (txmsg->reply.reply_type == 1)
+ DRM_DEBUG_KMS("link address nak received\n");
+ else {
+ DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
+ for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
+ DRM_DEBUG_KMS("port %d: input %d, pdt: %d, pn: %d, dpcd_rev: %02x, mcs: %d, ddps: %d, ldps %d, sdp %d/%d\n", i,
+ txmsg->reply.u.link_addr.ports[i].input_port,
+ txmsg->reply.u.link_addr.ports[i].peer_device_type,
+ txmsg->reply.u.link_addr.ports[i].port_number,
+ txmsg->reply.u.link_addr.ports[i].dpcd_revision,
+ txmsg->reply.u.link_addr.ports[i].mcs,
+ txmsg->reply.u.link_addr.ports[i].ddps,
+ txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
+ txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
+ txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
+ }
+ for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
+ drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
+ }
+ (*mgr->cbs->hotplug)(mgr);
+ }
+ } else
+ DRM_DEBUG_KMS("link address failed %d\n", ret);
+
+ kfree(txmsg);
+ return 0;
+}
+
+static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_branch *mstb,
+ struct drm_dp_mst_port *port)
+{
+ int len;
+ struct drm_dp_sideband_msg_tx *txmsg;
+ int ret;
+
+ txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
+ if (!txmsg)
+ return -ENOMEM;
+
+ txmsg->dst = mstb;
+ len = build_enum_path_resources(txmsg, port->port_num);
+
+ drm_dp_queue_down_tx(mgr, txmsg);
+
+ ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
+ if (ret > 0) {
+ if (txmsg->reply.reply_type == 1)
+ DRM_DEBUG_KMS("enum path resources nak received\n");
+ else {
+ if (port->port_num != txmsg->reply.u.path_resources.port_number)
+ DRM_ERROR("got incorrect port in response\n");
+ DRM_DEBUG_KMS("enum path resources %d: %d %d\n", txmsg->reply.u.path_resources.port_number, txmsg->reply.u.path_resources.full_payload_bw_number,
+ txmsg->reply.u.path_resources.avail_payload_bw_number);
+ port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
+ }
+ }
+
+ kfree(txmsg);
+ return 0;
+}
+
+static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port,
+ int id,
+ int pbn)
+{
+ struct drm_dp_sideband_msg_tx *txmsg;
+ struct drm_dp_mst_branch *mstb;
+ int len, ret;
+
+ mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
+ if (!mstb)
+ return -EINVAL;
+
+ txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
+ if (!txmsg) {
+ ret = -ENOMEM;
+ goto fail_put;
+ }
+
+ txmsg->dst = mstb;
+ len = build_allocate_payload(txmsg, port->port_num,
+ id,
+ pbn);
+
+ drm_dp_queue_down_tx(mgr, txmsg);
+
+ ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
+ if (ret > 0) {
+ if (txmsg->reply.reply_type == 1) {
+ ret = -EINVAL;
+ } else
+ ret = 0;
+ }
+ kfree(txmsg);
+fail_put:
+ drm_dp_put_mst_branch_device(mstb);
+ return ret;
+}
+
+static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
+ int id,
+ struct drm_dp_payload *payload)
+{
+ int ret;
+
+ ret = drm_dp_dpcd_write_payload(mgr, id, payload);
+ if (ret < 0) {
+ payload->payload_state = 0;
+ return ret;
+ }
+ payload->payload_state = DP_PAYLOAD_LOCAL;
+ return 0;
+}
+
+static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port,
+ int id,
+ struct drm_dp_payload *payload)
+{
+ int ret;
+ ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
+ if (ret < 0)
+ return ret;
+ payload->payload_state = DP_PAYLOAD_REMOTE;
+ return ret;
+}
+
+static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port,
+ int id,
+ struct drm_dp_payload *payload)
+{
+ DRM_DEBUG_KMS("\n");
+ /* its okay for these to fail */
+ if (port) {
+ drm_dp_payload_send_msg(mgr, port, id, 0);
+ }
+
+ drm_dp_dpcd_write_payload(mgr, id, payload);
+ payload->payload_state = DP_PAYLOAD_DELETE_LOCAL;
+ return 0;
+}
+
+static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
+ int id,
+ struct drm_dp_payload *payload)
+{
+ payload->payload_state = 0;
+ return 0;
+}
+
+/**
+ * drm_dp_update_payload_part1() - Execute payload update part 1
+ * @mgr: manager to use.
+ *
+ * This iterates over all proposed virtual channels, and tries to
+ * allocate space in the link for them. For 0->slots transitions,
+ * this step just writes the VCPI to the MST device. For slots->0
+ * transitions, this writes the updated VCPIs and removes the
+ * remote VC payloads.
+ *
+ * after calling this the driver should generate ACT and payload
+ * packets.
+ */
+int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
+{
+ int i, j;
+ int cur_slots = 1;
+ struct drm_dp_payload req_payload;
+ struct drm_dp_mst_port *port;
+
+ mutex_lock(&mgr->payload_lock);
+ for (i = 0; i < mgr->max_payloads; i++) {
+ /* solve the current payloads - compare to the hw ones
+ - update the hw view */
+ req_payload.start_slot = cur_slots;
+ if (mgr->proposed_vcpis[i]) {
+ port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
+ req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
+ } else {
+ port = NULL;
+ req_payload.num_slots = 0;
+ }
+
+ if (mgr->payloads[i].start_slot != req_payload.start_slot) {
+ mgr->payloads[i].start_slot = req_payload.start_slot;
+ }
+ /* work out what is required to happen with this payload */
+ if (mgr->payloads[i].num_slots != req_payload.num_slots) {
+
+ /* need to push an update for this payload */
+ if (req_payload.num_slots) {
+ drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload);
+ mgr->payloads[i].num_slots = req_payload.num_slots;
+ } else if (mgr->payloads[i].num_slots) {
+ mgr->payloads[i].num_slots = 0;
+ drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]);
+ req_payload.payload_state = mgr->payloads[i].payload_state;
+ mgr->payloads[i].start_slot = 0;
+ }
+ mgr->payloads[i].payload_state = req_payload.payload_state;
+ }
+ cur_slots += req_payload.num_slots;
+ }
+
+ for (i = 0; i < mgr->max_payloads; i++) {
+ if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
+ DRM_DEBUG_KMS("removing payload %d\n", i);
+ for (j = i; j < mgr->max_payloads - 1; j++) {
+ memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload));
+ mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1];
+ if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) {
+ set_bit(j + 1, &mgr->payload_mask);
+ } else {
+ clear_bit(j + 1, &mgr->payload_mask);
+ }
+ }
+ memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload));
+ mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL;
+ clear_bit(mgr->max_payloads, &mgr->payload_mask);
+
+ }
+ }
+ mutex_unlock(&mgr->payload_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_dp_update_payload_part1);
+
+/**
+ * drm_dp_update_payload_part2() - Execute payload update part 2
+ * @mgr: manager to use.
+ *
+ * This iterates over all proposed virtual channels, and tries to
+ * allocate space in the link for them. For 0->slots transitions,
+ * this step writes the remote VC payload commands. For slots->0
+ * this just resets some internal state.
+ */
+int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
+{
+ struct drm_dp_mst_port *port;
+ int i;
+ int ret = 0;
+ mutex_lock(&mgr->payload_lock);
+ for (i = 0; i < mgr->max_payloads; i++) {
+
+ if (!mgr->proposed_vcpis[i])
+ continue;
+
+ port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
+
+ DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
+ if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
+ ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
+ } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
+ ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
+ }
+ if (ret) {
+ mutex_unlock(&mgr->payload_lock);
+ return ret;
+ }
+ }
+ mutex_unlock(&mgr->payload_lock);
+ return 0;
+}
+EXPORT_SYMBOL(drm_dp_update_payload_part2);
+
+#if 0 /* unused as of yet */
+static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port,
+ int offset, int size)
+{
+ int len;
+ struct drm_dp_sideband_msg_tx *txmsg;
+
+ txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
+ if (!txmsg)
+ return -ENOMEM;
+
+ len = build_dpcd_read(txmsg, port->port_num, 0, 8);
+ txmsg->dst = port->parent;
+
+ drm_dp_queue_down_tx(mgr, txmsg);
+
+ return 0;
+}
+#endif
+
+static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port,
+ int offset, int size, u8 *bytes)
+{
+ int len;
+ int ret;
+ struct drm_dp_sideband_msg_tx *txmsg;
+ struct drm_dp_mst_branch *mstb;
+
+ mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
+ if (!mstb)
+ return -EINVAL;
+
+ txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
+ if (!txmsg) {
+ ret = -ENOMEM;
+ goto fail_put;
+ }
+
+ len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
+ txmsg->dst = mstb;
+
+ drm_dp_queue_down_tx(mgr, txmsg);
+
+ ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
+ if (ret > 0) {
+ if (txmsg->reply.reply_type == 1) {
+ ret = -EINVAL;
+ } else
+ ret = 0;
+ }
+ kfree(txmsg);
+fail_put:
+ drm_dp_put_mst_branch_device(mstb);
+ return ret;
+}
+
+static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
+{
+ struct drm_dp_sideband_msg_reply_body reply;
+
+ reply.reply_type = 1;
+ reply.req_type = req_type;
+ drm_dp_encode_sideband_reply(&reply, msg);
+ return 0;
+}
+
+static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_branch *mstb,
+ int req_type, int seqno, bool broadcast)
+{
+ struct drm_dp_sideband_msg_tx *txmsg;
+
+ txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
+ if (!txmsg)
+ return -ENOMEM;
+
+ txmsg->dst = mstb;
+ txmsg->seqno = seqno;
+ drm_dp_encode_up_ack_reply(txmsg, req_type);
+
+ mutex_lock(&mgr->qlock);
+ list_add_tail(&txmsg->next, &mgr->tx_msg_upq);
+ if (!mgr->tx_up_in_progress) {
+ process_single_up_tx_qlock(mgr);
+ }
+ mutex_unlock(&mgr->qlock);
+ return 0;
+}
+
+static bool drm_dp_get_vc_payload_bw(int dp_link_bw,
+ int dp_link_count,
+ int *out)
+{
+ switch (dp_link_bw) {
+ default:
+ DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n",
+ dp_link_bw, dp_link_count);
+ return false;
+
+ case DP_LINK_BW_1_62:
+ *out = 3 * dp_link_count;
+ break;
+ case DP_LINK_BW_2_7:
+ *out = 5 * dp_link_count;
+ break;
+ case DP_LINK_BW_5_4:
+ *out = 10 * dp_link_count;
+ break;
+ }
+ return true;
+}
+
+/**
+ * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
+ * @mgr: manager to set state for
+ * @mst_state: true to enable MST on this connector - false to disable.
+ *
+ * This is called by the driver when it detects an MST capable device plugged
+ * into a DP MST capable port, or when a DP MST capable device is unplugged.
+ */
+int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
+{
+ int ret = 0;
+ struct drm_dp_mst_branch *mstb = NULL;
+
+ mutex_lock(&mgr->lock);
+ if (mst_state == mgr->mst_state)
+ goto out_unlock;
+
+ mgr->mst_state = mst_state;
+ /* set the device into MST mode */
+ if (mst_state) {
+ WARN_ON(mgr->mst_primary);
+
+ /* get dpcd info */
+ ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
+ if (ret != DP_RECEIVER_CAP_SIZE) {
+ DRM_DEBUG_KMS("failed to read DPCD\n");
+ goto out_unlock;
+ }
+
+ if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1],
+ mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK,
+ &mgr->pbn_div)) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ mgr->total_pbn = 2560;
+ mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
+ mgr->avail_slots = mgr->total_slots;
+
+ /* add initial branch device at LCT 1 */
+ mstb = drm_dp_add_mst_branch_device(1, NULL);
+ if (mstb == NULL) {
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
+ mstb->mgr = mgr;
+
+ /* give this the main reference */
+ mgr->mst_primary = mstb;
+ kref_get(&mgr->mst_primary->kref);
+
+ {
+ struct drm_dp_payload reset_pay;
+ reset_pay.start_slot = 0;
+ reset_pay.num_slots = 0x3f;
+ drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
+ }
+
+ ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
+ DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
+ if (ret < 0) {
+ goto out_unlock;
+ }
+
+
+ /* sort out guid */
+ ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16);
+ if (ret != 16) {
+ DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret);
+ goto out_unlock;
+ }
+
+ mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid);
+ if (!mgr->guid_valid) {
+ ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16);
+ mgr->guid_valid = true;
+ }
+
+ queue_work(system_long_wq, &mgr->work);
+
+ ret = 0;
+ } else {
+ /* disable MST on the device */
+ mstb = mgr->mst_primary;
+ mgr->mst_primary = NULL;
+ /* this can fail if the device is gone */
+ drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
+ ret = 0;
+ memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
+ mgr->payload_mask = 0;
+ set_bit(0, &mgr->payload_mask);
+ mgr->vcpi_mask = 0;
+ }
+
+out_unlock:
+ mutex_unlock(&mgr->lock);
+ if (mstb)
+ drm_dp_put_mst_branch_device(mstb);
+ return ret;
+
+}
+EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
+
+/**
+ * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
+ * @mgr: manager to suspend
+ *
+ * This function tells the MST device that we can't handle UP messages
+ * anymore. This should stop it from sending any since we are suspended.
+ */
+void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
+{
+ mutex_lock(&mgr->lock);
+ drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
+ DP_MST_EN | DP_UPSTREAM_IS_SRC);
+ mutex_unlock(&mgr->lock);
+}
+EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
+
+/**
+ * drm_dp_mst_topology_mgr_resume() - resume the MST manager
+ * @mgr: manager to resume
+ *
+ * This will fetch DPCD and see if the device is still there,
+ * if it is, it will rewrite the MSTM control bits, and return.
+ *
+ * if the device fails this returns -1, and the driver should do
+ * a full MST reprobe, in case we were undocked.
+ */
+int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
+{
+ int ret = 0;
+
+ mutex_lock(&mgr->lock);
+
+ if (mgr->mst_primary) {
+ int sret;
+ sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
+ if (sret != DP_RECEIVER_CAP_SIZE) {
+ DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
+ ret = -1;
+ goto out_unlock;
+ }
+
+ ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
+ DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
+ if (ret < 0) {
+ DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
+ ret = -1;
+ goto out_unlock;
+ }
+ ret = 0;
+ } else
+ ret = -1;
+
+out_unlock:
+ mutex_unlock(&mgr->lock);
+ return ret;
+}
+EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
+
+static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
+{
+ int len;
+ u8 replyblock[32];
+ int replylen, origlen, curreply;
+ int ret;
+ struct drm_dp_sideband_msg_rx *msg;
+ int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
+ msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
+
+ len = min(mgr->max_dpcd_transaction_bytes, 16);
+ ret = drm_dp_dpcd_read(mgr->aux, basereg,
+ replyblock, len);
+ if (ret != len) {
+ DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
+ return;
+ }
+ ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
+ if (!ret) {
+ DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
+ return;
+ }
+ replylen = msg->curchunk_len + msg->curchunk_hdrlen;
+
+ origlen = replylen;
+ replylen -= len;
+ curreply = len;
+ while (replylen > 0) {
+ len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
+ ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
+ replyblock, len);
+ if (ret != len) {
+ DRM_DEBUG_KMS("failed to read a chunk\n");
+ }
+ ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
+ if (ret == false)
+ DRM_DEBUG_KMS("failed to build sideband msg\n");
+ curreply += len;
+ replylen -= len;
+ }
+}
+
+static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
+{
+ int ret = 0;
+
+ drm_dp_get_one_sb_msg(mgr, false);
+
+ if (mgr->down_rep_recv.have_eomt) {
+ struct drm_dp_sideband_msg_tx *txmsg;
+ struct drm_dp_mst_branch *mstb;
+ int slot = -1;
+ mstb = drm_dp_get_mst_branch_device(mgr,
+ mgr->down_rep_recv.initial_hdr.lct,
+ mgr->down_rep_recv.initial_hdr.rad);
+
+ if (!mstb) {
+ DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
+ memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
+ return 0;
+ }
+
+ /* find the message */
+ slot = mgr->down_rep_recv.initial_hdr.seqno;
+ mutex_lock(&mgr->qlock);
+ txmsg = mstb->tx_slots[slot];
+ /* remove from slots */
+ mutex_unlock(&mgr->qlock);
+
+ if (!txmsg) {
+ DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
+ mstb,
+ mgr->down_rep_recv.initial_hdr.seqno,
+ mgr->down_rep_recv.initial_hdr.lct,
+ mgr->down_rep_recv.initial_hdr.rad[0],
+ mgr->down_rep_recv.msg[0]);
+ drm_dp_put_mst_branch_device(mstb);
+ memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
+ return 0;
+ }
+
+ drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
+ if (txmsg->reply.reply_type == 1) {
+ DRM_DEBUG_KMS("Got NAK reply: req 0x%02x, reason 0x%02x, nak data 0x%02x\n", txmsg->reply.req_type, txmsg->reply.u.nak.reason, txmsg->reply.u.nak.nak_data);
+ }
+
+ memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
+ drm_dp_put_mst_branch_device(mstb);
+
+ mutex_lock(&mgr->qlock);
+ txmsg->state = DRM_DP_SIDEBAND_TX_RX;
+ mstb->tx_slots[slot] = NULL;
+ mutex_unlock(&mgr->qlock);
+
+ wake_up(&mgr->tx_waitq);
+ }
+ return ret;
+}
+
+static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
+{
+ int ret = 0;
+ drm_dp_get_one_sb_msg(mgr, true);
+
+ if (mgr->up_req_recv.have_eomt) {
+ struct drm_dp_sideband_msg_req_body msg;
+ struct drm_dp_mst_branch *mstb;
+ bool seqno;
+ mstb = drm_dp_get_mst_branch_device(mgr,
+ mgr->up_req_recv.initial_hdr.lct,
+ mgr->up_req_recv.initial_hdr.rad);
+ if (!mstb) {
+ DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
+ memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
+ return 0;
+ }
+
+ seqno = mgr->up_req_recv.initial_hdr.seqno;
+ drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
+
+ if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
+ drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
+ drm_dp_update_port(mstb, &msg.u.conn_stat);
+ DRM_DEBUG_KMS("Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n", msg.u.conn_stat.port_number, msg.u.conn_stat.legacy_device_plug_status, msg.u.conn_stat.displayport_device_plug_status, msg.u.conn_stat.message_capability_status, msg.u.conn_stat.input_port, msg.u.conn_stat.peer_device_type);
+ (*mgr->cbs->hotplug)(mgr);
+
+ } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
+ drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
+ DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
+ }
+
+ drm_dp_put_mst_branch_device(mstb);
+ memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
+ }
+ return ret;
+}
+
+/**
+ * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
+ * @mgr: manager to notify irq for.
+ * @esi: 4 bytes from SINK_COUNT_ESI
+ * @handled: whether the hpd interrupt was consumed or not
+ *
+ * This should be called from the driver when it detects a short IRQ,
+ * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
+ * topology manager will process the sideband messages received as a result
+ * of this.
+ */
+int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
+{
+ int ret = 0;
+ int sc;
+ *handled = false;
+ sc = esi[0] & 0x3f;
+
+ if (sc != mgr->sink_count) {
+ mgr->sink_count = sc;
+ *handled = true;
+ }
+
+ if (esi[1] & DP_DOWN_REP_MSG_RDY) {
+ ret = drm_dp_mst_handle_down_rep(mgr);
+ *handled = true;
+ }
+
+ if (esi[1] & DP_UP_REQ_MSG_RDY) {
+ ret |= drm_dp_mst_handle_up_req(mgr);
+ *handled = true;
+ }
+
+ drm_dp_mst_kick_tx(mgr);
+ return ret;
+}
+EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
+
+/**
+ * drm_dp_mst_detect_port() - get connection status for an MST port
+ * @mgr: manager for this port
+ * @port: unverified pointer to a port
+ *
+ * This returns the current connection state for a port. It validates the
+ * port pointer still exists so the caller doesn't require a reference
+ */
+enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector,
+ struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
+{
+ enum drm_connector_status status = connector_status_disconnected;
+
+ /* we need to search for the port in the mgr in case its gone */
+ port = drm_dp_get_validated_port_ref(mgr, port);
+ if (!port)
+ return connector_status_disconnected;
+
+ if (!port->ddps)
+ goto out;
+
+ switch (port->pdt) {
+ case DP_PEER_DEVICE_NONE:
+ case DP_PEER_DEVICE_MST_BRANCHING:
+ break;
+
+ case DP_PEER_DEVICE_SST_SINK:
+ status = connector_status_connected;
+ /* for logical ports - cache the EDID */
+ if (port->port_num >= 8 && !port->cached_edid) {
+ port->cached_edid = drm_get_edid(connector, &port->aux.ddc);
+ }
+ break;
+ case DP_PEER_DEVICE_DP_LEGACY_CONV:
+ if (port->ldps)
+ status = connector_status_connected;
+ break;
+ }
+out:
+ drm_dp_put_port(port);
+ return status;
+}
+EXPORT_SYMBOL(drm_dp_mst_detect_port);
+
+/**
+ * drm_dp_mst_get_edid() - get EDID for an MST port
+ * @connector: toplevel connector to get EDID for
+ * @mgr: manager for this port
+ * @port: unverified pointer to a port.
+ *
+ * This returns an EDID for the port connected to a connector,
+ * It validates the pointer still exists so the caller doesn't require a
+ * reference.
+ */
+struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
+{
+ struct edid *edid = NULL;
+
+ /* we need to search for the port in the mgr in case its gone */
+ port = drm_dp_get_validated_port_ref(mgr, port);
+ if (!port)
+ return NULL;
+
+ if (port->cached_edid)
+ edid = drm_edid_duplicate(port->cached_edid);
+ else
+ edid = drm_get_edid(connector, &port->aux.ddc);
+
+ drm_mode_connector_set_tile_property(connector);
+ drm_dp_put_port(port);
+ return edid;
+}
+EXPORT_SYMBOL(drm_dp_mst_get_edid);
+
+/**
+ * drm_dp_find_vcpi_slots() - find slots for this PBN value
+ * @mgr: manager to use
+ * @pbn: payload bandwidth to convert into slots.
+ */
+int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
+ int pbn)
+{
+ int num_slots;
+
+ num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
+
+ if (num_slots > mgr->avail_slots)
+ return -ENOSPC;
+ return num_slots;
+}
+EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
+
+static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_vcpi *vcpi, int pbn)
+{
+ int num_slots;
+ int ret;
+
+ num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
+
+ if (num_slots > mgr->avail_slots)
+ return -ENOSPC;
+
+ vcpi->pbn = pbn;
+ vcpi->aligned_pbn = num_slots * mgr->pbn_div;
+ vcpi->num_slots = num_slots;
+
+ ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+/**
+ * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
+ * @mgr: manager for this port
+ * @port: port to allocate a virtual channel for.
+ * @pbn: payload bandwidth number to request
+ * @slots: returned number of slots for this PBN.
+ */
+bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
+{
+ int ret;
+
+ port = drm_dp_get_validated_port_ref(mgr, port);
+ if (!port)
+ return false;
+
+ if (port->vcpi.vcpi > 0) {
+ DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
+ if (pbn == port->vcpi.pbn) {
+ *slots = port->vcpi.num_slots;
+ return true;
+ }
+ }
+
+ ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
+ if (ret) {
+ DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
+ goto out;
+ }
+ DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
+ *slots = port->vcpi.num_slots;
+
+ drm_dp_put_port(port);
+ return true;
+out:
+ return false;
+}
+EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
+
+int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
+{
+ int slots = 0;
+ port = drm_dp_get_validated_port_ref(mgr, port);
+ if (!port)
+ return slots;
+
+ slots = port->vcpi.num_slots;
+ drm_dp_put_port(port);
+ return slots;
+}
+EXPORT_SYMBOL(drm_dp_mst_get_vcpi_slots);
+
+/**
+ * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
+ * @mgr: manager for this port
+ * @port: unverified pointer to a port.
+ *
+ * This just resets the number of slots for the ports VCPI for later programming.
+ */
+void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
+{
+ port = drm_dp_get_validated_port_ref(mgr, port);
+ if (!port)
+ return;
+ port->vcpi.num_slots = 0;
+ drm_dp_put_port(port);
+}
+EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
+
+/**
+ * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
+ * @mgr: manager for this port
+ * @port: unverified port to deallocate vcpi for
+ */
+void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
+{
+ port = drm_dp_get_validated_port_ref(mgr, port);
+ if (!port)
+ return;
+
+ drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
+ port->vcpi.num_slots = 0;
+ port->vcpi.pbn = 0;
+ port->vcpi.aligned_pbn = 0;
+ port->vcpi.vcpi = 0;
+ drm_dp_put_port(port);
+}
+EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
+
+static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
+ int id, struct drm_dp_payload *payload)
+{
+ u8 payload_alloc[3], status;
+ int ret;
+ int retries = 0;
+
+ drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
+ DP_PAYLOAD_TABLE_UPDATED);
+
+ payload_alloc[0] = id;
+ payload_alloc[1] = payload->start_slot;
+ payload_alloc[2] = payload->num_slots;
+
+ ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
+ if (ret != 3) {
+ DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
+ goto fail;
+ }
+
+retry:
+ ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
+ if (ret < 0) {
+ DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
+ goto fail;
+ }
+
+ if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
+ retries++;
+ if (retries < 20) {
+ usleep_range(10000, 20000);
+ goto retry;
+ }
+ DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
+ ret = -EINVAL;
+ goto fail;
+ }
+ ret = 0;
+fail:
+ return ret;
+}
+
+
+/**
+ * drm_dp_check_act_status() - Check ACT handled status.
+ * @mgr: manager to use
+ *
+ * Check the payload status bits in the DPCD for ACT handled completion.
+ */
+int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
+{
+ u8 status;
+ int ret;
+ int count = 0;
+
+ do {
+ ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
+
+ if (ret < 0) {
+ DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
+ goto fail;
+ }
+
+ if (status & DP_PAYLOAD_ACT_HANDLED)
+ break;
+ count++;
+ udelay(100);
+
+ } while (count < 30);
+
+ if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
+ DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
+ ret = -EINVAL;
+ goto fail;
+ }
+ return 0;
+fail:
+ return ret;
+}
+EXPORT_SYMBOL(drm_dp_check_act_status);
+
+/**
+ * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
+ * @clock: dot clock for the mode
+ * @bpp: bpp for the mode.
+ *
+ * This uses the formula in the spec to calculate the PBN value for a mode.
+ */
+int drm_dp_calc_pbn_mode(int clock, int bpp)
+{
+ fixed20_12 pix_bw;
+ fixed20_12 fbpp;
+ fixed20_12 result;
+ fixed20_12 margin, tmp;
+ u32 res;
+
+ pix_bw.full = dfixed_const(clock);
+ fbpp.full = dfixed_const(bpp);
+ tmp.full = dfixed_const(8);
+ fbpp.full = dfixed_div(fbpp, tmp);
+
+ result.full = dfixed_mul(pix_bw, fbpp);
+ margin.full = dfixed_const(54);
+ tmp.full = dfixed_const(64);
+ margin.full = dfixed_div(margin, tmp);
+ result.full = dfixed_div(result, margin);
+
+ margin.full = dfixed_const(1006);
+ tmp.full = dfixed_const(1000);
+ margin.full = dfixed_div(margin, tmp);
+ result.full = dfixed_mul(result, margin);
+
+ result.full = dfixed_div(result, tmp);
+ result.full = dfixed_ceil(result);
+ res = dfixed_trunc(result);
+ return res;
+}
+EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
+
+static int test_calc_pbn_mode(void)
+{
+ int ret;
+ ret = drm_dp_calc_pbn_mode(154000, 30);
+ if (ret != 689)
+ return -EINVAL;
+ ret = drm_dp_calc_pbn_mode(234000, 30);
+ if (ret != 1047)
+ return -EINVAL;
+ return 0;
+}
+
+/* we want to kick the TX after we've ack the up/down IRQs. */
+static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
+{
+ queue_work(system_long_wq, &mgr->tx_work);
+}
+
+static void drm_dp_mst_dump_mstb(struct seq_file *m,
+ struct drm_dp_mst_branch *mstb)
+{
+ struct drm_dp_mst_port *port;
+ int tabs = mstb->lct;
+ char prefix[10];
+ int i;
+
+ for (i = 0; i < tabs; i++)
+ prefix[i] = '\t';
+ prefix[i] = '\0';
+
+ seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
+ list_for_each_entry(port, &mstb->ports, next) {
+ seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector);
+ if (port->mstb)
+ drm_dp_mst_dump_mstb(m, port->mstb);
+ }
+}
+
+static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
+ char *buf)
+{
+ int ret;
+ int i;
+ for (i = 0; i < 4; i++) {
+ ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
+ if (ret != 16)
+ break;
+ }
+ if (i == 4)
+ return true;
+ return false;
+}
+
+/**
+ * drm_dp_mst_dump_topology(): dump topology to seq file.
+ * @m: seq_file to dump output to
+ * @mgr: manager to dump current topology for.
+ *
+ * helper to dump MST topology to a seq file for debugfs.
+ */
+void drm_dp_mst_dump_topology(struct seq_file *m,
+ struct drm_dp_mst_topology_mgr *mgr)
+{
+ int i;
+ struct drm_dp_mst_port *port;
+ mutex_lock(&mgr->lock);
+ if (mgr->mst_primary)
+ drm_dp_mst_dump_mstb(m, mgr->mst_primary);
+
+ /* dump VCPIs */
+ mutex_unlock(&mgr->lock);
+
+ mutex_lock(&mgr->payload_lock);
+ seq_printf(m, "vcpi: %lx %lx\n", mgr->payload_mask, mgr->vcpi_mask);
+
+ for (i = 0; i < mgr->max_payloads; i++) {
+ if (mgr->proposed_vcpis[i]) {
+ port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
+ seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots);
+ } else
+ seq_printf(m, "vcpi %d:unsed\n", i);
+ }
+ for (i = 0; i < mgr->max_payloads; i++) {
+ seq_printf(m, "payload %d: %d, %d, %d\n",
+ i,
+ mgr->payloads[i].payload_state,
+ mgr->payloads[i].start_slot,
+ mgr->payloads[i].num_slots);
+
+
+ }
+ mutex_unlock(&mgr->payload_lock);
+
+ mutex_lock(&mgr->lock);
+ if (mgr->mst_primary) {
+ u8 buf[64];
+ bool bret;
+ int ret;
+ ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
+ seq_printf(m, "dpcd: ");
+ for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
+ seq_printf(m, "%02x ", buf[i]);
+ seq_printf(m, "\n");
+ ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
+ seq_printf(m, "faux/mst: ");
+ for (i = 0; i < 2; i++)
+ seq_printf(m, "%02x ", buf[i]);
+ seq_printf(m, "\n");
+ ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
+ seq_printf(m, "mst ctrl: ");
+ for (i = 0; i < 1; i++)
+ seq_printf(m, "%02x ", buf[i]);
+ seq_printf(m, "\n");
+
+ bret = dump_dp_payload_table(mgr, buf);
+ if (bret == true) {
+ seq_printf(m, "payload table: ");
+ for (i = 0; i < 63; i++)
+ seq_printf(m, "%02x ", buf[i]);
+ seq_printf(m, "\n");
+ }
+
+ }
+
+ mutex_unlock(&mgr->lock);
+
+}
+EXPORT_SYMBOL(drm_dp_mst_dump_topology);
+
+static void drm_dp_tx_work(struct work_struct *work)
+{
+ struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
+
+ mutex_lock(&mgr->qlock);
+ if (mgr->tx_down_in_progress)
+ process_single_down_tx_qlock(mgr);
+ mutex_unlock(&mgr->qlock);
+}
+
+/**
+ * drm_dp_mst_topology_mgr_init - initialise a topology manager
+ * @mgr: manager struct to initialise
+ * @dev: device providing this structure - for i2c addition.
+ * @aux: DP helper aux channel to talk to this device
+ * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
+ * @max_payloads: maximum number of payloads this GPU can source
+ * @conn_base_id: the connector object ID the MST device is connected to.
+ *
+ * Return 0 for success, or negative error code on failure
+ */
+int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
+ struct device *dev, struct drm_dp_aux *aux,
+ int max_dpcd_transaction_bytes,
+ int max_payloads, int conn_base_id)
+{
+ mutex_init(&mgr->lock);
+ mutex_init(&mgr->qlock);
+ mutex_init(&mgr->payload_lock);
+ INIT_LIST_HEAD(&mgr->tx_msg_upq);
+ INIT_LIST_HEAD(&mgr->tx_msg_downq);
+ INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
+ INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
+ init_waitqueue_head(&mgr->tx_waitq);
+ mgr->dev = dev;
+ mgr->aux = aux;
+ mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
+ mgr->max_payloads = max_payloads;
+ mgr->conn_base_id = conn_base_id;
+ mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
+ if (!mgr->payloads)
+ return -ENOMEM;
+ mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
+ if (!mgr->proposed_vcpis)
+ return -ENOMEM;
+ set_bit(0, &mgr->payload_mask);
+ test_calc_pbn_mode();
+ return 0;
+}
+EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
+
+/**
+ * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
+ * @mgr: manager to destroy
+ */
+void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
+{
+ mutex_lock(&mgr->payload_lock);
+ kfree(mgr->payloads);
+ mgr->payloads = NULL;
+ kfree(mgr->proposed_vcpis);
+ mgr->proposed_vcpis = NULL;
+ mutex_unlock(&mgr->payload_lock);
+ mgr->dev = NULL;
+ mgr->aux = NULL;
+}
+EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
+
+/* I2C device */
+static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
+ int num)
+{
+ struct drm_dp_aux *aux = adapter->algo_data;
+ struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
+ struct drm_dp_mst_branch *mstb;
+ struct drm_dp_mst_topology_mgr *mgr = port->mgr;
+ unsigned int i;
+ bool reading = false;
+ struct drm_dp_sideband_msg_req_body msg;
+ struct drm_dp_sideband_msg_tx *txmsg = NULL;
+ int ret;
+
+ mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
+ if (!mstb)
+ return -EREMOTEIO;
+
+ /* construct i2c msg */
+ /* see if last msg is a read */
+ if (msgs[num - 1].flags & I2C_M_RD)
+ reading = true;
+
+ if (!reading) {
+ DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
+ ret = -EIO;
+ goto out;
+ }
+
+ msg.req_type = DP_REMOTE_I2C_READ;
+ msg.u.i2c_read.num_transactions = num - 1;
+ msg.u.i2c_read.port_number = port->port_num;
+ for (i = 0; i < num - 1; i++) {
+ msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
+ msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
+ msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
+ }
+ msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
+ msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
+
+ txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
+ if (!txmsg) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ txmsg->dst = mstb;
+ drm_dp_encode_sideband_req(&msg, txmsg);
+
+ drm_dp_queue_down_tx(mgr, txmsg);
+
+ ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
+ if (ret > 0) {
+
+ if (txmsg->reply.reply_type == 1) { /* got a NAK back */
+ ret = -EREMOTEIO;
+ goto out;
+ }
+ if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
+ ret = -EIO;
+ goto out;
+ }
+ memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
+ ret = num;
+ }
+out:
+ kfree(txmsg);
+ drm_dp_put_mst_branch_device(mstb);
+ return ret;
+}
+
+static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
+ I2C_FUNC_SMBUS_READ_BLOCK_DATA |
+ I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
+ I2C_FUNC_10BIT_ADDR;
+}
+
+static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
+ .functionality = drm_dp_mst_i2c_functionality,
+ .master_xfer = drm_dp_mst_i2c_xfer,
+};
+
+/**
+ * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
+ * @aux: DisplayPort AUX channel
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
+{
+ aux->ddc.algo = &drm_dp_mst_i2c_algo;
+ aux->ddc.algo_data = aux;
+ aux->ddc.retries = 3;
+
+ aux->ddc.class = I2C_CLASS_DDC;
+ aux->ddc.owner = THIS_MODULE;
+ aux->ddc.dev.parent = aux->dev;
+ aux->ddc.dev.of_node = aux->dev->of_node;
+
+ strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
+ sizeof(aux->ddc.name));
+
+ return i2c_add_adapter(&aux->ddc);
+}
+
+/**
+ * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
+ * @aux: DisplayPort AUX channel
+ */
+static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
+{
+ i2c_del_adapter(&aux->ddc);
+}
Code Review / kvmfornfv.git / blobdiff