diff options
Diffstat (limited to 'drivers/gpu/drm/drm_dp_mst_topology.c')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_mst_topology.c | 2712 |
1 files changed, 2712 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c new file mode 100644 index 000000000000..73bc773513f2 --- /dev/null +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -0,0 +1,2712 @@ +/* + * 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/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; + + 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; + } + + set_bit(ret, &mgr->payload_mask); + vcpi->vcpi = ret; + 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 id) +{ + if (id == 0) + return; + + mutex_lock(&mgr->payload_lock); + DRM_DEBUG_KMS("putting payload %d\n", id); + clear_bit(id, &mgr->payload_mask); + mgr->proposed_vcpis[id - 1] = NULL; + 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; + mutex_lock(&mgr->qlock); + ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX || + txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT); + mutex_unlock(&mgr->qlock); + 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) +{ + 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: + drm_dp_put_mst_branch_device(port->mstb); + port->mstb = NULL; + 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; + 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) +{ + int i; + char temp[8]; + snprintf(proppath, 255, "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, 8, "-%d", port_num); + strncat(proppath, temp, 255); + } + snprintf(temp, 8, "-%d", port->port_num); + strncat(proppath, temp, 255); +} + +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); + port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath); + } + + /* 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; + + 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; +} + +/* must be called holding qlock */ +static void process_single_down_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_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; +} + +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; +} + +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; +} + +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 = 0; + return 0; +} + +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; + 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; + } + /* work out what is required to happen with this payload */ + if (mgr->payloads[i].start_slot != req_payload.start_slot || + 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, i + 1, &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, i + 1, &mgr->payloads[i]); + req_payload.payload_state = mgr->payloads[i].payload_state; + } else + req_payload.payload_state = 0; + + mgr->payloads[i].start_slot = req_payload.start_slot; + mgr->payloads[i].payload_state = req_payload.payload_state; + } + cur_slots += req_payload.num_slots; + } + 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; + 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, i + 1, &mgr->payloads[i]); + } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) { + ret = drm_dp_destroy_payload_step2(mgr, i + 1, &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 int drm_dp_get_vc_payload_bw(int dp_link_bw, int dp_link_count) +{ + switch (dp_link_bw) { + case DP_LINK_BW_1_62: + return 3 * dp_link_count; + case DP_LINK_BW_2_7: + return 5 * dp_link_count; + case DP_LINK_BW_5_4: + return 10 * dp_link_count; + } + return 0; +} + +/** + * 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; + } + + mgr->pbn_div = drm_dp_get_vc_payload_bw(mgr->dpcd[1], mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK); + 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); + } + +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 + * + * 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_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; + 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; + + edid = drm_get_edid(connector, &port->aux.ddc); + 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); + +/** + * 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\n", mgr->payload_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); +} |