include/drm/drm_dp_mst_helper.h

   1 /*
   2  * Copyright © 2014 Red Hat.
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and its
   5  * documentation for any purpose is hereby granted without fee, provided that
   6  * the above copyright notice appear in all copies and that both that copyright
   7  * notice and this permission notice appear in supporting documentation, and
   8  * that the name of the copyright holders not be used in advertising or
   9  * publicity pertaining to distribution of the software without specific,
  10  * written prior permission.  The copyright holders make no representations
  11  * about the suitability of this software for any purpose.  It is provided "as
  12  * is" without express or implied warranty.
  13  *
  14  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  15  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  16  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  17  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  18  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  19  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  20  * OF THIS SOFTWARE.
  21  */
  22 #ifndef _DRM_DP_MST_HELPER_H_
  23 #define _DRM_DP_MST_HELPER_H_
  24
  25 #include <linux/types.h>
  26 #include <drm/drm_dp_helper.h>
  27 #include <drm/drm_atomic.h>
  28
  29 #if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS)
  30 #include <linux/stackdepot.h>
  31 #include <linux/timekeeping.h>
  32
  33 enum drm_dp_mst_topology_ref_type {
  34         DRM_DP_MST_TOPOLOGY_REF_GET,
  35         DRM_DP_MST_TOPOLOGY_REF_PUT,
  36 };
  37
  38 struct drm_dp_mst_topology_ref_history {
  39         struct drm_dp_mst_topology_ref_entry {
  40                 enum drm_dp_mst_topology_ref_type type;
  41                 int count;
  42                 ktime_t ts_nsec;
  43                 depot_stack_handle_t backtrace;
  44         } *entries;
  45         int len;
  46 };
  47 #endif /* IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS) */
  48
  49 struct drm_dp_mst_branch;
  50
  51 /**
  52  * struct drm_dp_vcpi - Virtual Channel Payload Identifier
  53  * @vcpi: Virtual channel ID.
  54  * @pbn: Payload Bandwidth Number for this channel
  55  * @aligned_pbn: PBN aligned with slot size
  56  * @num_slots: number of slots for this PBN
  57  */
  58 struct drm_dp_vcpi {
  59         int vcpi;
  60         int pbn;
  61         int aligned_pbn;
  62         int num_slots;
  63 };
  64
  65 /**
  66  * struct drm_dp_mst_port - MST port
  67  * @port_num: port number
  68  * @input: if this port is an input port. Protected by
  69  * &drm_dp_mst_topology_mgr.base.lock.
  70  * @mcs: message capability status - DP 1.2 spec. Protected by
  71  * &drm_dp_mst_topology_mgr.base.lock.
  72  * @ddps: DisplayPort Device Plug Status - DP 1.2. Protected by
  73  * &drm_dp_mst_topology_mgr.base.lock.
  74  * @pdt: Peer Device Type. Protected by
  75  * &drm_dp_mst_topology_mgr.base.lock.
  76  * @ldps: Legacy Device Plug Status. Protected by
  77  * &drm_dp_mst_topology_mgr.base.lock.
  78  * @dpcd_rev: DPCD revision of device on this port. Protected by
  79  * &drm_dp_mst_topology_mgr.base.lock.
  80  * @num_sdp_streams: Number of simultaneous streams. Protected by
  81  * &drm_dp_mst_topology_mgr.base.lock.
  82  * @num_sdp_stream_sinks: Number of stream sinks. Protected by
  83  * &drm_dp_mst_topology_mgr.base.lock.
  84  * @full_pbn: Max possible bandwidth for this port. Protected by
  85  * &drm_dp_mst_topology_mgr.base.lock.
  86  * @next: link to next port on this branch device
  87  * @aux: i2c aux transport to talk to device connected to this port, protected
  88  * by &drm_dp_mst_topology_mgr.base.lock.
  89  * @parent: branch device parent of this port
  90  * @vcpi: Virtual Channel Payload info for this port.
  91  * @connector: DRM connector this port is connected to. Protected by
  92  * &drm_dp_mst_topology_mgr.base.lock.
  93  * @mgr: topology manager this port lives under.
  94  *
  95  * This structure represents an MST port endpoint on a device somewhere
  96  * in the MST topology.
  97  */
  98 struct drm_dp_mst_port {
  99         /**
 100          * @topology_kref: refcount for this port's lifetime in the topology,
 101          * only the DP MST helpers should need to touch this
 102          */
 103         struct kref topology_kref;
 104
 105         /**
 106          * @malloc_kref: refcount for the memory allocation containing this
 107          * structure. See drm_dp_mst_get_port_malloc() and
 108          * drm_dp_mst_put_port_malloc().
 109          */
 110         struct kref malloc_kref;
 111
 112 #if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS)
 113         /**
 114          * @topology_ref_history: A history of each topology
 115          * reference/dereference. See CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS.
 116          */
 117         struct drm_dp_mst_topology_ref_history topology_ref_history;
 118 #endif
 119
 120         u8 port_num;
 121         bool input;
 122         bool mcs;
 123         bool ddps;
 124         u8 pdt;
 125         bool ldps;
 126         u8 dpcd_rev;
 127         u8 num_sdp_streams;
 128         u8 num_sdp_stream_sinks;
 129         uint16_t full_pbn;
 130         struct list_head next;
 131         /**
 132          * @mstb: the branch device connected to this port, if there is one.
 133          * This should be considered protected for reading by
 134          * &drm_dp_mst_topology_mgr.lock. There are two exceptions to this:
 135          * &drm_dp_mst_topology_mgr.up_req_work and
 136          * &drm_dp_mst_topology_mgr.work, which do not grab
 137          * &drm_dp_mst_topology_mgr.lock during reads but are the only
 138          * updaters of this list and are protected from writing concurrently
 139          * by &drm_dp_mst_topology_mgr.probe_lock.
 140          */
 141         struct drm_dp_mst_branch *mstb;
 142         struct drm_dp_aux aux; /* i2c bus for this port? */
 143         struct drm_dp_mst_branch *parent;
 144
 145         struct drm_dp_vcpi vcpi;
 146         struct drm_connector *connector;
 147         struct drm_dp_mst_topology_mgr *mgr;
 148
 149         /**
 150          * @cached_edid: for DP logical ports - make tiling work by ensuring
 151          * that the EDID for all connectors is read immediately.
 152          */
 153         struct edid *cached_edid;
 154         /**
 155          * @has_audio: Tracks whether the sink connector to this port is
 156          * audio-capable.
 157          */
 158         bool has_audio;
 159
 160         /**
 161          * @fec_capable: bool indicating if FEC can be supported up to that
 162          * point in the MST topology.
 163          */
 164         bool fec_capable;
 165 };
 166
 167 /* sideband msg header - not bit struct */
 168 struct drm_dp_sideband_msg_hdr {
 169         u8 lct;
 170         u8 lcr;
 171         u8 rad[8];
 172         bool broadcast;
 173         bool path_msg;
 174         u8 msg_len;
 175         bool somt;
 176         bool eomt;
 177         bool seqno;
 178 };
 179
 180 struct drm_dp_sideband_msg_rx {
 181         u8 chunk[48];
 182         u8 msg[256];
 183         u8 curchunk_len;
 184         u8 curchunk_idx; /* chunk we are parsing now */
 185         u8 curchunk_hdrlen;
 186         u8 curlen; /* total length of the msg */
 187         bool have_somt;
 188         bool have_eomt;
 189         struct drm_dp_sideband_msg_hdr initial_hdr;
 190 };
 191
 192 /**
 193  * struct drm_dp_mst_branch - MST branch device.
 194  * @rad: Relative Address to talk to this branch device.
 195  * @lct: Link count total to talk to this branch device.
 196  * @num_ports: number of ports on the branch.
 197  * @port_parent: pointer to the port parent, NULL if toplevel.
 198  * @mgr: topology manager for this branch device.
 199  * @link_address_sent: if a link address message has been sent to this device yet.
 200  * @guid: guid for DP 1.2 branch device. port under this branch can be
 201  * identified by port #.
 202  *
 203  * This structure represents an MST branch device, there is one
 204  * primary branch device at the root, along with any other branches connected
 205  * to downstream port of parent branches.
 206  */
 207 struct drm_dp_mst_branch {
 208         /**
 209          * @topology_kref: refcount for this branch device's lifetime in the
 210          * topology, only the DP MST helpers should need to touch this
 211          */
 212         struct kref topology_kref;
 213
 214         /**
 215          * @malloc_kref: refcount for the memory allocation containing this
 216          * structure. See drm_dp_mst_get_mstb_malloc() and
 217          * drm_dp_mst_put_mstb_malloc().
 218          */
 219         struct kref malloc_kref;
 220
 221 #if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS)
 222         /**
 223          * @topology_ref_history: A history of each topology
 224          * reference/dereference. See CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS.
 225          */
 226         struct drm_dp_mst_topology_ref_history topology_ref_history;
 227 #endif
 228
 229         /**
 230          * @destroy_next: linked-list entry used by
 231          * drm_dp_delayed_destroy_work()
 232          */
 233         struct list_head destroy_next;
 234
 235         u8 rad[8];
 236         u8 lct;
 237         int num_ports;
 238
 239         /**
 240          * @ports: the list of ports on this branch device. This should be
 241          * considered protected for reading by &drm_dp_mst_topology_mgr.lock.
 242          * There are two exceptions to this:
 243          * &drm_dp_mst_topology_mgr.up_req_work and
 244          * &drm_dp_mst_topology_mgr.work, which do not grab
 245          * &drm_dp_mst_topology_mgr.lock during reads but are the only
 246          * updaters of this list and are protected from updating the list
 247          * concurrently by @drm_dp_mst_topology_mgr.probe_lock
 248          */
 249         struct list_head ports;
 250
 251         struct drm_dp_mst_port *port_parent;
 252         struct drm_dp_mst_topology_mgr *mgr;
 253
 254         bool link_address_sent;
 255
 256         /* global unique identifier to identify branch devices */
 257         u8 guid[16];
 258 };
 259
 260
 261 struct drm_dp_nak_reply {
 262         u8 guid[16];
 263         u8 reason;
 264         u8 nak_data;
 265 };
 266
 267 struct drm_dp_link_address_ack_reply {
 268         u8 guid[16];
 269         u8 nports;
 270         struct drm_dp_link_addr_reply_port {
 271                 bool input_port;
 272                 u8 peer_device_type;
 273                 u8 port_number;
 274                 bool mcs;
 275                 bool ddps;
 276                 bool legacy_device_plug_status;
 277                 u8 dpcd_revision;
 278                 u8 peer_guid[16];
 279                 u8 num_sdp_streams;
 280                 u8 num_sdp_stream_sinks;
 281         } ports[16];
 282 };
 283
 284 struct drm_dp_remote_dpcd_read_ack_reply {
 285         u8 port_number;
 286         u8 num_bytes;
 287         u8 bytes[255];
 288 };
 289
 290 struct drm_dp_remote_dpcd_write_ack_reply {
 291         u8 port_number;
 292 };
 293
 294 struct drm_dp_remote_dpcd_write_nak_reply {
 295         u8 port_number;
 296         u8 reason;
 297         u8 bytes_written_before_failure;
 298 };
 299
 300 struct drm_dp_remote_i2c_read_ack_reply {
 301         u8 port_number;
 302         u8 num_bytes;
 303         u8 bytes[255];
 304 };
 305
 306 struct drm_dp_remote_i2c_read_nak_reply {
 307         u8 port_number;
 308         u8 nak_reason;
 309         u8 i2c_nak_transaction;
 310 };
 311
 312 struct drm_dp_remote_i2c_write_ack_reply {
 313         u8 port_number;
 314 };
 315
 316 struct drm_dp_query_stream_enc_status_ack_reply {
 317         /* Bit[23:16]- Stream Id */
 318         u8 stream_id;
 319
 320         /* Bit[15]- Signed */
 321         bool reply_signed;
 322
 323         /* Bit[10:8]- Stream Output Sink Type */
 324         bool unauthorizable_device_present;
 325         bool legacy_device_present;
 326         bool query_capable_device_present;
 327
 328         /* Bit[12:11]- Stream Output CP Type */
 329         bool hdcp_1x_device_present;
 330         bool hdcp_2x_device_present;
 331
 332         /* Bit[4]- Stream Authentication */
 333         bool auth_completed;
 334
 335         /* Bit[3]- Stream Encryption */
 336         bool encryption_enabled;
 337
 338         /* Bit[2]- Stream Repeater Function Present */
 339         bool repeater_present;
 340
 341         /* Bit[1:0]- Stream State */
 342         u8 state;
 343 };
 344
 345 #define DRM_DP_MAX_SDP_STREAMS 16
 346 struct drm_dp_allocate_payload {
 347         u8 port_number;
 348         u8 number_sdp_streams;
 349         u8 vcpi;
 350         u16 pbn;
 351         u8 sdp_stream_sink[DRM_DP_MAX_SDP_STREAMS];
 352 };
 353
 354 struct drm_dp_allocate_payload_ack_reply {
 355         u8 port_number;
 356         u8 vcpi;
 357         u16 allocated_pbn;
 358 };
 359
 360 struct drm_dp_connection_status_notify {
 361         u8 guid[16];
 362         u8 port_number;
 363         bool legacy_device_plug_status;
 364         bool displayport_device_plug_status;
 365         bool message_capability_status;
 366         bool input_port;
 367         u8 peer_device_type;
 368 };
 369
 370 struct drm_dp_remote_dpcd_read {
 371         u8 port_number;
 372         u32 dpcd_address;
 373         u8 num_bytes;
 374 };
 375
 376 struct drm_dp_remote_dpcd_write {
 377         u8 port_number;
 378         u32 dpcd_address;
 379         u8 num_bytes;
 380         u8 *bytes;
 381 };
 382
 383 #define DP_REMOTE_I2C_READ_MAX_TRANSACTIONS 4
 384 struct drm_dp_remote_i2c_read {
 385         u8 num_transactions;
 386         u8 port_number;
 387         struct drm_dp_remote_i2c_read_tx {
 388                 u8 i2c_dev_id;
 389                 u8 num_bytes;
 390                 u8 *bytes;
 391                 u8 no_stop_bit;
 392                 u8 i2c_transaction_delay;
 393         } transactions[DP_REMOTE_I2C_READ_MAX_TRANSACTIONS];
 394         u8 read_i2c_device_id;
 395         u8 num_bytes_read;
 396 };
 397
 398 struct drm_dp_remote_i2c_write {
 399         u8 port_number;
 400         u8 write_i2c_device_id;
 401         u8 num_bytes;
 402         u8 *bytes;
 403 };
 404
 405 struct drm_dp_query_stream_enc_status {
 406         u8 stream_id;
 407         u8 client_id[7];        /* 56-bit nonce */
 408         u8 stream_event;
 409         bool valid_stream_event;
 410         u8 stream_behavior;
 411         u8 valid_stream_behavior;
 412 };
 413
 414 /* this covers ENUM_RESOURCES, POWER_DOWN_PHY, POWER_UP_PHY */
 415 struct drm_dp_port_number_req {
 416         u8 port_number;
 417 };
 418
 419 struct drm_dp_enum_path_resources_ack_reply {
 420         u8 port_number;
 421         bool fec_capable;
 422         u16 full_payload_bw_number;
 423         u16 avail_payload_bw_number;
 424 };
 425
 426 /* covers POWER_DOWN_PHY, POWER_UP_PHY */
 427 struct drm_dp_port_number_rep {
 428         u8 port_number;
 429 };
 430
 431 struct drm_dp_query_payload {
 432         u8 port_number;
 433         u8 vcpi;
 434 };
 435
 436 struct drm_dp_resource_status_notify {
 437         u8 port_number;
 438         u8 guid[16];
 439         u16 available_pbn;
 440 };
 441
 442 struct drm_dp_query_payload_ack_reply {
 443         u8 port_number;
 444         u16 allocated_pbn;
 445 };
 446
 447 struct drm_dp_sideband_msg_req_body {
 448         u8 req_type;
 449         union ack_req {
 450                 struct drm_dp_connection_status_notify conn_stat;
 451                 struct drm_dp_port_number_req port_num;
 452                 struct drm_dp_resource_status_notify resource_stat;
 453
 454                 struct drm_dp_query_payload query_payload;
 455                 struct drm_dp_allocate_payload allocate_payload;
 456
 457                 struct drm_dp_remote_dpcd_read dpcd_read;
 458                 struct drm_dp_remote_dpcd_write dpcd_write;
 459
 460                 struct drm_dp_remote_i2c_read i2c_read;
 461                 struct drm_dp_remote_i2c_write i2c_write;
 462
 463                 struct drm_dp_query_stream_enc_status enc_status;
 464         } u;
 465 };
 466
 467 struct drm_dp_sideband_msg_reply_body {
 468         u8 reply_type;
 469         u8 req_type;
 470         union ack_replies {
 471                 struct drm_dp_nak_reply nak;
 472                 struct drm_dp_link_address_ack_reply link_addr;
 473                 struct drm_dp_port_number_rep port_number;
 474
 475                 struct drm_dp_enum_path_resources_ack_reply path_resources;
 476                 struct drm_dp_allocate_payload_ack_reply allocate_payload;
 477                 struct drm_dp_query_payload_ack_reply query_payload;
 478
 479                 struct drm_dp_remote_dpcd_read_ack_reply remote_dpcd_read_ack;
 480                 struct drm_dp_remote_dpcd_write_ack_reply remote_dpcd_write_ack;
 481                 struct drm_dp_remote_dpcd_write_nak_reply remote_dpcd_write_nack;
 482
 483                 struct drm_dp_remote_i2c_read_ack_reply remote_i2c_read_ack;
 484                 struct drm_dp_remote_i2c_read_nak_reply remote_i2c_read_nack;
 485                 struct drm_dp_remote_i2c_write_ack_reply remote_i2c_write_ack;
 486
 487                 struct drm_dp_query_stream_enc_status_ack_reply enc_status;
 488         } u;
 489 };
 490
 491 /* msg is queued to be put into a slot */
 492 #define DRM_DP_SIDEBAND_TX_QUEUED 0
 493 /* msg has started transmitting on a slot - still on msgq */
 494 #define DRM_DP_SIDEBAND_TX_START_SEND 1
 495 /* msg has finished transmitting on a slot - removed from msgq only in slot */
 496 #define DRM_DP_SIDEBAND_TX_SENT 2
 497 /* msg has received a response - removed from slot */
 498 #define DRM_DP_SIDEBAND_TX_RX 3
 499 #define DRM_DP_SIDEBAND_TX_TIMEOUT 4
 500
 501 struct drm_dp_sideband_msg_tx {
 502         u8 msg[256];
 503         u8 chunk[48];
 504         u8 cur_offset;
 505         u8 cur_len;
 506         struct drm_dp_mst_branch *dst;
 507         struct list_head next;
 508         int seqno;
 509         int state;
 510         bool path_msg;
 511         struct drm_dp_sideband_msg_reply_body reply;
 512 };
 513
 514 /* sideband msg handler */
 515 struct drm_dp_mst_topology_mgr;
 516 struct drm_dp_mst_topology_cbs {
 517         /* create a connector for a port */
 518         struct drm_connector *(*add_connector)(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, const char *path);
 519         /*
 520          * Checks for any pending MST interrupts, passing them to MST core for
 521          * processing, the same way an HPD IRQ pulse handler would do this.
 522          * If provided MST core calls this callback from a poll-waiting loop
 523          * when waiting for MST down message replies. The driver is expected
 524          * to guard against a race between this callback and the driver's HPD
 525          * IRQ pulse handler.
 526          */
 527         void (*poll_hpd_irq)(struct drm_dp_mst_topology_mgr *mgr);
 528 };
 529
 530 #define DP_MAX_PAYLOAD (sizeof(unsigned long) * 8)
 531
 532 #define DP_PAYLOAD_LOCAL 1
 533 #define DP_PAYLOAD_REMOTE 2
 534 #define DP_PAYLOAD_DELETE_LOCAL 3
 535
 536 struct drm_dp_payload {
 537         int payload_state;
 538         int start_slot;
 539         int num_slots;
 540         int vcpi;
 541 };
 542
 543 #define to_dp_mst_topology_state(x) container_of(x, struct drm_dp_mst_topology_state, base)
 544
 545 struct drm_dp_vcpi_allocation {
 546         struct drm_dp_mst_port *port;
 547         int vcpi;
 548         int pbn;
 549         bool dsc_enabled;
 550         struct list_head next;
 551 };
 552
 553 struct drm_dp_mst_topology_state {
 554         struct drm_private_state base;
 555         struct list_head vcpis;
 556         struct drm_dp_mst_topology_mgr *mgr;
 557 };
 558
 559 #define to_dp_mst_topology_mgr(x) container_of(x, struct drm_dp_mst_topology_mgr, base)
 560
 561 /**
 562  * struct drm_dp_mst_topology_mgr - DisplayPort MST manager
 563  *
 564  * This struct represents the toplevel displayport MST topology manager.
 565  * There should be one instance of this for every MST capable DP connector
 566  * on the GPU.
 567  */
 568 struct drm_dp_mst_topology_mgr {
 569         /**
 570          * @base: Base private object for atomic
 571          */
 572         struct drm_private_obj base;
 573
 574         /**
 575          * @dev: device pointer for adding i2c devices etc.
 576          */
 577         struct drm_device *dev;
 578         /**
 579          * @cbs: callbacks for connector addition and destruction.
 580          */
 581         const struct drm_dp_mst_topology_cbs *cbs;
 582         /**
 583          * @max_dpcd_transaction_bytes: maximum number of bytes to read/write
 584          * in one go.
 585          */
 586         int max_dpcd_transaction_bytes;
 587         /**
 588          * @aux: AUX channel for the DP MST connector this topolgy mgr is
 589          * controlling.
 590          */
 591         struct drm_dp_aux *aux;
 592         /**
 593          * @max_payloads: maximum number of payloads the GPU can generate.
 594          */
 595         int max_payloads;
 596         /**
 597          * @conn_base_id: DRM connector ID this mgr is connected to. Only used
 598          * to build the MST connector path value.
 599          */
 600         int conn_base_id;
 601
 602         /**
 603          * @up_req_recv: Message receiver state for up requests.
 604          */
 605         struct drm_dp_sideband_msg_rx up_req_recv;
 606
 607         /**
 608          * @down_rep_recv: Message receiver state for replies to down
 609          * requests.
 610          */
 611         struct drm_dp_sideband_msg_rx down_rep_recv;
 612
 613         /**
 614          * @lock: protects @mst_state, @mst_primary, @dpcd, and
 615          * @payload_id_table_cleared.
 616          */
 617         struct mutex lock;
 618
 619         /**
 620          * @probe_lock: Prevents @work and @up_req_work, the only writers of
 621          * &drm_dp_mst_port.mstb and &drm_dp_mst_branch.ports, from racing
 622          * while they update the topology.
 623          */
 624         struct mutex probe_lock;
 625
 626         /**
 627          * @mst_state: If this manager is enabled for an MST capable port. False
 628          * if no MST sink/branch devices is connected.
 629          */
 630         bool mst_state : 1;
 631
 632         /**
 633          * @payload_id_table_cleared: Whether or not we've cleared the payload
 634          * ID table for @mst_primary. Protected by @lock.
 635          */
 636         bool payload_id_table_cleared : 1;
 637
 638         /**
 639          * @mst_primary: Pointer to the primary/first branch device.
 640          */
 641         struct drm_dp_mst_branch *mst_primary;
 642
 643         /**
 644          * @dpcd: Cache of DPCD for primary port.
 645          */
 646         u8 dpcd[DP_RECEIVER_CAP_SIZE];
 647         /**
 648          * @sink_count: Sink count from DEVICE_SERVICE_IRQ_VECTOR_ESI0.
 649          */
 650         u8 sink_count;
 651         /**
 652          * @pbn_div: PBN to slots divisor.
 653          */
 654         int pbn_div;
 655
 656         /**
 657          * @funcs: Atomic helper callbacks
 658          */
 659         const struct drm_private_state_funcs *funcs;
 660
 661         /**
 662          * @qlock: protects @tx_msg_downq and &drm_dp_sideband_msg_tx.state
 663          */
 664         struct mutex qlock;
 665
 666         /**
 667          * @tx_msg_downq: List of pending down requests
 668          */
 669         struct list_head tx_msg_downq;
 670
 671         /**
 672          * @payload_lock: Protect payload information.
 673          */
 674         struct mutex payload_lock;
 675         /**
 676          * @proposed_vcpis: Array of pointers for the new VCPI allocation. The
 677          * VCPI structure itself is &drm_dp_mst_port.vcpi, and the size of
 678          * this array is determined by @max_payloads.
 679          */
 680         struct drm_dp_vcpi **proposed_vcpis;
 681         /**
 682          * @payloads: Array of payloads. The size of this array is determined
 683          * by @max_payloads.
 684          */
 685         struct drm_dp_payload *payloads;
 686         /**
 687          * @payload_mask: Elements of @payloads actually in use. Since
 688          * reallocation of active outputs isn't possible gaps can be created by
 689          * disabling outputs out of order compared to how they've been enabled.
 690          */
 691         unsigned long payload_mask;
 692         /**
 693          * @vcpi_mask: Similar to @payload_mask, but for @proposed_vcpis.
 694          */
 695         unsigned long vcpi_mask;
 696
 697         /**
 698          * @tx_waitq: Wait to queue stall for the tx worker.
 699          */
 700         wait_queue_head_t tx_waitq;
 701         /**
 702          * @work: Probe work.
 703          */
 704         struct work_struct work;
 705         /**
 706          * @tx_work: Sideband transmit worker. This can nest within the main
 707          * @work worker for each transaction @work launches.
 708          */
 709         struct work_struct tx_work;
 710
 711         /**
 712          * @destroy_port_list: List of to be destroyed connectors.
 713          */
 714         struct list_head destroy_port_list;
 715         /**
 716          * @destroy_branch_device_list: List of to be destroyed branch
 717          * devices.
 718          */
 719         struct list_head destroy_branch_device_list;
 720         /**
 721          * @delayed_destroy_lock: Protects @destroy_port_list and
 722          * @destroy_branch_device_list.
 723          */
 724         struct mutex delayed_destroy_lock;
 725
 726         /**
 727          * @delayed_destroy_wq: Workqueue used for delayed_destroy_work items.
 728          * A dedicated WQ makes it possible to drain any requeued work items
 729          * on it.
 730          */
 731         struct workqueue_struct *delayed_destroy_wq;
 732
 733         /**
 734          * @delayed_destroy_work: Work item to destroy MST port and branch
 735          * devices, needed to avoid locking inversion.
 736          */
 737         struct work_struct delayed_destroy_work;
 738
 739         /**
 740          * @up_req_list: List of pending up requests from the topology that
 741          * need to be processed, in chronological order.
 742          */
 743         struct list_head up_req_list;
 744         /**
 745          * @up_req_lock: Protects @up_req_list
 746          */
 747         struct mutex up_req_lock;
 748         /**
 749          * @up_req_work: Work item to process up requests received from the
 750          * topology. Needed to avoid blocking hotplug handling and sideband
 751          * transmissions.
 752          */
 753         struct work_struct up_req_work;
 754
 755 #if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS)
 756         /**
 757          * @topology_ref_history_lock: protects
 758          * &drm_dp_mst_port.topology_ref_history and
 759          * &drm_dp_mst_branch.topology_ref_history.
 760          */
 761         struct mutex topology_ref_history_lock;
 762 #endif
 763 };
 764
 765 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
 766                                  struct drm_device *dev, struct drm_dp_aux *aux,
 767                                  int max_dpcd_transaction_bytes,
 768                                  int max_payloads, int conn_base_id);
 769
 770 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr);
 771
 772 bool drm_dp_read_mst_cap(struct drm_dp_aux *aux, const u8 dpcd[DP_RECEIVER_CAP_SIZE]);
 773 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state);
 774
 775 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled);
 776
 777
 778 int
 779 drm_dp_mst_detect_port(struct drm_connector *connector,
 780                        struct drm_modeset_acquire_ctx *ctx,
 781                        struct drm_dp_mst_topology_mgr *mgr,
 782                        struct drm_dp_mst_port *port);
 783
 784 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
 785
 786
 787 int drm_dp_calc_pbn_mode(int clock, int bpp, bool dsc);
 788
 789 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 790                               struct drm_dp_mst_port *port, int pbn, int slots);
 791
 792 int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
 793
 794
 795 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
 796
 797
 798 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 799                                 struct drm_dp_mst_port *port);
 800
 801
 802 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
 803                            int pbn);
 804
 805
 806 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
 807
 808
 809 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);
 810
 811 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr);
 812
 813 void drm_dp_mst_dump_topology(struct seq_file *m,
 814                               struct drm_dp_mst_topology_mgr *mgr);
 815
 816 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr);
 817 int __must_check
 818 drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr,
 819                                bool sync);
 820
 821 ssize_t drm_dp_mst_dpcd_read(struct drm_dp_aux *aux,
 822                              unsigned int offset, void *buffer, size_t size);
 823 ssize_t drm_dp_mst_dpcd_write(struct drm_dp_aux *aux,
 824                               unsigned int offset, void *buffer, size_t size);
 825
 826 int drm_dp_mst_connector_late_register(struct drm_connector *connector,
 827                                        struct drm_dp_mst_port *port);
 828 void drm_dp_mst_connector_early_unregister(struct drm_connector *connector,
 829                                            struct drm_dp_mst_port *port);
 830
 831 struct drm_dp_mst_topology_state *drm_atomic_get_mst_topology_state(struct drm_atomic_state *state,
 832                                                                     struct drm_dp_mst_topology_mgr *mgr);
 833 int __must_check
 834 drm_dp_atomic_find_vcpi_slots(struct drm_atomic_state *state,
 835                               struct drm_dp_mst_topology_mgr *mgr,
 836                               struct drm_dp_mst_port *port, int pbn,
 837                               int pbn_div);
 838 int drm_dp_mst_atomic_enable_dsc(struct drm_atomic_state *state,
 839                                  struct drm_dp_mst_port *port,
 840                                  int pbn, int pbn_div,
 841                                  bool enable);
 842 int __must_check
 843 drm_dp_mst_add_affected_dsc_crtcs(struct drm_atomic_state *state,
 844                                   struct drm_dp_mst_topology_mgr *mgr);
 845 int __must_check
 846 drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
 847                                  struct drm_dp_mst_topology_mgr *mgr,
 848                                  struct drm_dp_mst_port *port);
 849 int drm_dp_send_power_updown_phy(struct drm_dp_mst_topology_mgr *mgr,
 850                                  struct drm_dp_mst_port *port, bool power_up);
 851 int drm_dp_send_query_stream_enc_status(struct drm_dp_mst_topology_mgr *mgr,
 852                 struct drm_dp_mst_port *port,
 853                 struct drm_dp_query_stream_enc_status_ack_reply *status);
 854 int __must_check drm_dp_mst_atomic_check(struct drm_atomic_state *state);
 855
 856 void drm_dp_mst_get_port_malloc(struct drm_dp_mst_port *port);
 857 void drm_dp_mst_put_port_malloc(struct drm_dp_mst_port *port);
 858
 859 struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port);
 860
 861 extern const struct drm_private_state_funcs drm_dp_mst_topology_state_funcs;
 862
 863 /**
 864  * __drm_dp_mst_state_iter_get - private atomic state iterator function for
 865  * macro-internal use
 866  * @state: &struct drm_atomic_state pointer
 867  * @mgr: pointer to the &struct drm_dp_mst_topology_mgr iteration cursor
 868  * @old_state: optional pointer to the old &struct drm_dp_mst_topology_state
 869  * iteration cursor
 870  * @new_state: optional pointer to the new &struct drm_dp_mst_topology_state
 871  * iteration cursor
 872  * @i: int iteration cursor, for macro-internal use
 873  *
 874  * Used by for_each_oldnew_mst_mgr_in_state(),
 875  * for_each_old_mst_mgr_in_state(), and for_each_new_mst_mgr_in_state(). Don't
 876  * call this directly.
 877  *
 878  * Returns:
 879  * True if the current &struct drm_private_obj is a &struct
 880  * drm_dp_mst_topology_mgr, false otherwise.
 881  */
 882 static inline bool
 883 __drm_dp_mst_state_iter_get(struct drm_atomic_state *state,
 884                             struct drm_dp_mst_topology_mgr **mgr,
 885                             struct drm_dp_mst_topology_state **old_state,
 886                             struct drm_dp_mst_topology_state **new_state,
 887                             int i)
 888 {
 889         struct __drm_private_objs_state *objs_state = &state->private_objs[i];
 890
 891         if (objs_state->ptr->funcs != &drm_dp_mst_topology_state_funcs)
 892                 return false;
 893
 894         *mgr = to_dp_mst_topology_mgr(objs_state->ptr);
 895         if (old_state)
 896                 *old_state = to_dp_mst_topology_state(objs_state->old_state);
 897         if (new_state)
 898                 *new_state = to_dp_mst_topology_state(objs_state->new_state);
 899
 900         return true;
 901 }
 902
 903 /**
 904  * for_each_oldnew_mst_mgr_in_state - iterate over all DP MST topology
 905  * managers in an atomic update
 906  * @__state: &struct drm_atomic_state pointer
 907  * @mgr: &struct drm_dp_mst_topology_mgr iteration cursor
 908  * @old_state: &struct drm_dp_mst_topology_state iteration cursor for the old
 909  * state
 910  * @new_state: &struct drm_dp_mst_topology_state iteration cursor for the new
 911  * state
 912  * @__i: int iteration cursor, for macro-internal use
 913  *
 914  * This iterates over all DRM DP MST topology managers in an atomic update,
 915  * tracking both old and new state. This is useful in places where the state
 916  * delta needs to be considered, for example in atomic check functions.
 917  */
 918 #define for_each_oldnew_mst_mgr_in_state(__state, mgr, old_state, new_state, __i) \
 919         for ((__i) = 0; (__i) < (__state)->num_private_objs; (__i)++) \
 920                 for_each_if(__drm_dp_mst_state_iter_get((__state), &(mgr), &(old_state), &(new_state), (__i)))
 921
 922 /**
 923  * for_each_old_mst_mgr_in_state - iterate over all DP MST topology managers
 924  * in an atomic update
 925  * @__state: &struct drm_atomic_state pointer
 926  * @mgr: &struct drm_dp_mst_topology_mgr iteration cursor
 927  * @old_state: &struct drm_dp_mst_topology_state iteration cursor for the old
 928  * state
 929  * @__i: int iteration cursor, for macro-internal use
 930  *
 931  * This iterates over all DRM DP MST topology managers in an atomic update,
 932  * tracking only the old state. This is useful in disable functions, where we
 933  * need the old state the hardware is still in.
 934  */
 935 #define for_each_old_mst_mgr_in_state(__state, mgr, old_state, __i) \
 936         for ((__i) = 0; (__i) < (__state)->num_private_objs; (__i)++) \
 937                 for_each_if(__drm_dp_mst_state_iter_get((__state), &(mgr), &(old_state), NULL, (__i)))
 938
 939 /**
 940  * for_each_new_mst_mgr_in_state - iterate over all DP MST topology managers
 941  * in an atomic update
 942  * @__state: &struct drm_atomic_state pointer
 943  * @mgr: &struct drm_dp_mst_topology_mgr iteration cursor
 944  * @new_state: &struct drm_dp_mst_topology_state iteration cursor for the new
 945  * state
 946  * @__i: int iteration cursor, for macro-internal use
 947  *
 948  * This iterates over all DRM DP MST topology managers in an atomic update,
 949  * tracking only the new state. This is useful in enable functions, where we
 950  * need the new state the hardware should be in when the atomic commit
 951  * operation has completed.
 952  */
 953 #define for_each_new_mst_mgr_in_state(__state, mgr, new_state, __i) \
 954         for ((__i) = 0; (__i) < (__state)->num_private_objs; (__i)++) \
 955                 for_each_if(__drm_dp_mst_state_iter_get((__state), &(mgr), NULL, &(new_state), (__i)))
 956
 957 #endif