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
 28struct drm_dp_mst_branch;
 29
 30/**
 31 * struct drm_dp_vcpi - Virtual Channel Payload Identifier
 32 * @vcpi: Virtual channel ID.
 33 * @pbn: Payload Bandwidth Number for this channel
 34 * @aligned_pbn: PBN aligned with slot size
 35 * @num_slots: number of slots for this PBN
 36 */
 37struct drm_dp_vcpi {
 38	int vcpi;
 39	int pbn;
 40	int aligned_pbn;
 41	int num_slots;
 42};
 43
 44/**
 45 * struct drm_dp_mst_port - MST port
 46 * @kref: reference count for this port.
 47 * @port_num: port number
 48 * @input: if this port is an input port.
 49 * @mcs: message capability status - DP 1.2 spec.
 50 * @ddps: DisplayPort Device Plug Status - DP 1.2
 51 * @pdt: Peer Device Type
 52 * @ldps: Legacy Device Plug Status
 53 * @dpcd_rev: DPCD revision of device on this port
 54 * @num_sdp_streams: Number of simultaneous streams
 55 * @num_sdp_stream_sinks: Number of stream sinks
 56 * @available_pbn: Available bandwidth for this port.
 57 * @next: link to next port on this branch device
 58 * @mstb: branch device attach below this port
 59 * @aux: i2c aux transport to talk to device connected to this port.
 60 * @parent: branch device parent of this port
 61 * @vcpi: Virtual Channel Payload info for this port.
 62 * @connector: DRM connector this port is connected to.
 63 * @mgr: topology manager this port lives under.
 64 *
 65 * This structure represents an MST port endpoint on a device somewhere
 66 * in the MST topology.
 67 */
 68struct drm_dp_mst_port {
 69	struct kref kref;
 70
 71	u8 port_num;
 72	bool input;
 73	bool mcs;
 74	bool ddps;
 75	u8 pdt;
 76	bool ldps;
 77	u8 dpcd_rev;
 78	u8 num_sdp_streams;
 79	u8 num_sdp_stream_sinks;
 80	uint16_t available_pbn;
 81	struct list_head next;
 82	struct drm_dp_mst_branch *mstb; /* pointer to an mstb if this port has one */
 83	struct drm_dp_aux aux; /* i2c bus for this port? */
 84	struct drm_dp_mst_branch *parent;
 85
 86	struct drm_dp_vcpi vcpi;
 87	struct drm_connector *connector;
 88	struct drm_dp_mst_topology_mgr *mgr;
 89
 90	/**
 91	 * @cached_edid: for DP logical ports - make tiling work by ensuring
 92	 * that the EDID for all connectors is read immediately.
 93	 */
 94	struct edid *cached_edid;
 95	/**
 96	 * @has_audio: Tracks whether the sink connector to this port is
 97	 * audio-capable.
 98	 */
 99	bool has_audio;
100};
101
102/**
103 * struct drm_dp_mst_branch - MST branch device.
104 * @kref: reference count for this port.
105 * @rad: Relative Address to talk to this branch device.
106 * @lct: Link count total to talk to this branch device.
107 * @num_ports: number of ports on the branch.
108 * @msg_slots: one bit per transmitted msg slot.
109 * @ports: linked list of ports on this branch.
110 * @port_parent: pointer to the port parent, NULL if toplevel.
111 * @mgr: topology manager for this branch device.
112 * @tx_slots: transmission slots for this device.
113 * @last_seqno: last sequence number used to talk to this.
114 * @link_address_sent: if a link address message has been sent to this device yet.
115 * @guid: guid for DP 1.2 branch device. port under this branch can be
116 * identified by port #.
117 *
118 * This structure represents an MST branch device, there is one
119 * primary branch device at the root, along with any other branches connected
120 * to downstream port of parent branches.
121 */
122struct drm_dp_mst_branch {
123	struct kref kref;
124	u8 rad[8];
125	u8 lct;
126	int num_ports;
127
128	int msg_slots;
129	struct list_head ports;
130
131	/* list of tx ops queue for this port */
132	struct drm_dp_mst_port *port_parent;
133	struct drm_dp_mst_topology_mgr *mgr;
134
135	/* slots are protected by mstb->mgr->qlock */
136	struct drm_dp_sideband_msg_tx *tx_slots[2];
137	int last_seqno;
138	bool link_address_sent;
139
140	/* global unique identifier to identify branch devices */
141	u8 guid[16];
142};
143
144
145/* sideband msg header - not bit struct */
146struct drm_dp_sideband_msg_hdr {
147	u8 lct;
148	u8 lcr;
149	u8 rad[8];
150	bool broadcast;
151	bool path_msg;
152	u8 msg_len;
153	bool somt;
154	bool eomt;
155	bool seqno;
156};
157
158struct drm_dp_nak_reply {
159	u8 guid[16];
160	u8 reason;
161	u8 nak_data;
162};
163
164struct drm_dp_link_address_ack_reply {
165	u8 guid[16];
166	u8 nports;
167	struct drm_dp_link_addr_reply_port {
168		bool input_port;
169		u8 peer_device_type;
170		u8 port_number;
171		bool mcs;
172		bool ddps;
173		bool legacy_device_plug_status;
174		u8 dpcd_revision;
175		u8 peer_guid[16];
176		u8 num_sdp_streams;
177		u8 num_sdp_stream_sinks;
178	} ports[16];
179};
180
181struct drm_dp_remote_dpcd_read_ack_reply {
182	u8 port_number;
183	u8 num_bytes;
184	u8 bytes[255];
185};
186
187struct drm_dp_remote_dpcd_write_ack_reply {
188	u8 port_number;
189};
190
191struct drm_dp_remote_dpcd_write_nak_reply {
192	u8 port_number;
193	u8 reason;
194	u8 bytes_written_before_failure;
195};
196
197struct drm_dp_remote_i2c_read_ack_reply {
198	u8 port_number;
199	u8 num_bytes;
200	u8 bytes[255];
201};
202
203struct drm_dp_remote_i2c_read_nak_reply {
204	u8 port_number;
205	u8 nak_reason;
206	u8 i2c_nak_transaction;
207};
208
209struct drm_dp_remote_i2c_write_ack_reply {
210	u8 port_number;
211};
212
213
214struct drm_dp_sideband_msg_rx {
215	u8 chunk[48];
216	u8 msg[256];
217	u8 curchunk_len;
218	u8 curchunk_idx; /* chunk we are parsing now */
219	u8 curchunk_hdrlen;
220	u8 curlen; /* total length of the msg */
221	bool have_somt;
222	bool have_eomt;
223	struct drm_dp_sideband_msg_hdr initial_hdr;
224};
225
226#define DRM_DP_MAX_SDP_STREAMS 16
227struct drm_dp_allocate_payload {
228	u8 port_number;
229	u8 number_sdp_streams;
230	u8 vcpi;
231	u16 pbn;
232	u8 sdp_stream_sink[DRM_DP_MAX_SDP_STREAMS];
233};
234
235struct drm_dp_allocate_payload_ack_reply {
236	u8 port_number;
237	u8 vcpi;
238	u16 allocated_pbn;
239};
240
241struct drm_dp_connection_status_notify {
242	u8 guid[16];
243	u8 port_number;
244	bool legacy_device_plug_status;
245	bool displayport_device_plug_status;
246	bool message_capability_status;
247	bool input_port;
248	u8 peer_device_type;
249};
250
251struct drm_dp_remote_dpcd_read {
252	u8 port_number;
253	u32 dpcd_address;
254	u8 num_bytes;
255};
256
257struct drm_dp_remote_dpcd_write {
258	u8 port_number;
259	u32 dpcd_address;
260	u8 num_bytes;
261	u8 *bytes;
262};
263
264#define DP_REMOTE_I2C_READ_MAX_TRANSACTIONS 4
265struct drm_dp_remote_i2c_read {
266	u8 num_transactions;
267	u8 port_number;
268	struct {
269		u8 i2c_dev_id;
270		u8 num_bytes;
271		u8 *bytes;
272		u8 no_stop_bit;
273		u8 i2c_transaction_delay;
274	} transactions[DP_REMOTE_I2C_READ_MAX_TRANSACTIONS];
275	u8 read_i2c_device_id;
276	u8 num_bytes_read;
277};
278
279struct drm_dp_remote_i2c_write {
280	u8 port_number;
281	u8 write_i2c_device_id;
282	u8 num_bytes;
283	u8 *bytes;
284};
285
286/* this covers ENUM_RESOURCES, POWER_DOWN_PHY, POWER_UP_PHY */
287struct drm_dp_port_number_req {
288	u8 port_number;
289};
290
291struct drm_dp_enum_path_resources_ack_reply {
292	u8 port_number;
293	u16 full_payload_bw_number;
294	u16 avail_payload_bw_number;
295};
296
297/* covers POWER_DOWN_PHY, POWER_UP_PHY */
298struct drm_dp_port_number_rep {
299	u8 port_number;
300};
301
302struct drm_dp_query_payload {
303	u8 port_number;
304	u8 vcpi;
305};
306
307struct drm_dp_resource_status_notify {
308	u8 port_number;
309	u8 guid[16];
310	u16 available_pbn;
311};
312
313struct drm_dp_query_payload_ack_reply {
314	u8 port_number;
315	u8 allocated_pbn;
316};
317
318struct drm_dp_sideband_msg_req_body {
319	u8 req_type;
320	union ack_req {
321		struct drm_dp_connection_status_notify conn_stat;
322		struct drm_dp_port_number_req port_num;
323		struct drm_dp_resource_status_notify resource_stat;
324
325		struct drm_dp_query_payload query_payload;
326		struct drm_dp_allocate_payload allocate_payload;
327
328		struct drm_dp_remote_dpcd_read dpcd_read;
329		struct drm_dp_remote_dpcd_write dpcd_write;
330
331		struct drm_dp_remote_i2c_read i2c_read;
332		struct drm_dp_remote_i2c_write i2c_write;
333	} u;
334};
335
336struct drm_dp_sideband_msg_reply_body {
337	u8 reply_type;
338	u8 req_type;
339	union ack_replies {
340		struct drm_dp_nak_reply nak;
341		struct drm_dp_link_address_ack_reply link_addr;
342		struct drm_dp_port_number_rep port_number;
343
344		struct drm_dp_enum_path_resources_ack_reply path_resources;
345		struct drm_dp_allocate_payload_ack_reply allocate_payload;
346		struct drm_dp_query_payload_ack_reply query_payload;
347
348		struct drm_dp_remote_dpcd_read_ack_reply remote_dpcd_read_ack;
349		struct drm_dp_remote_dpcd_write_ack_reply remote_dpcd_write_ack;
350		struct drm_dp_remote_dpcd_write_nak_reply remote_dpcd_write_nack;
351
352		struct drm_dp_remote_i2c_read_ack_reply remote_i2c_read_ack;
353		struct drm_dp_remote_i2c_read_nak_reply remote_i2c_read_nack;
354		struct drm_dp_remote_i2c_write_ack_reply remote_i2c_write_ack;
355	} u;
356};
357
358/* msg is queued to be put into a slot */
359#define DRM_DP_SIDEBAND_TX_QUEUED 0
360/* msg has started transmitting on a slot - still on msgq */
361#define DRM_DP_SIDEBAND_TX_START_SEND 1
362/* msg has finished transmitting on a slot - removed from msgq only in slot */
363#define DRM_DP_SIDEBAND_TX_SENT 2
364/* msg has received a response - removed from slot */
365#define DRM_DP_SIDEBAND_TX_RX 3
366#define DRM_DP_SIDEBAND_TX_TIMEOUT 4
367
368struct drm_dp_sideband_msg_tx {
369	u8 msg[256];
370	u8 chunk[48];
371	u8 cur_offset;
372	u8 cur_len;
373	struct drm_dp_mst_branch *dst;
374	struct list_head next;
375	int seqno;
376	int state;
377	bool path_msg;
378	struct drm_dp_sideband_msg_reply_body reply;
379};
380
381/* sideband msg handler */
382struct drm_dp_mst_topology_mgr;
383struct drm_dp_mst_topology_cbs {
384	/* create a connector for a port */
385	struct drm_connector *(*add_connector)(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, const char *path);
386	void (*register_connector)(struct drm_connector *connector);
387	void (*destroy_connector)(struct drm_dp_mst_topology_mgr *mgr,
388				  struct drm_connector *connector);
389	void (*hotplug)(struct drm_dp_mst_topology_mgr *mgr);
390
391};
392
393#define DP_MAX_PAYLOAD (sizeof(unsigned long) * 8)
394
395#define DP_PAYLOAD_LOCAL 1
396#define DP_PAYLOAD_REMOTE 2
397#define DP_PAYLOAD_DELETE_LOCAL 3
398
399struct drm_dp_payload {
400	int payload_state;
401	int start_slot;
402	int num_slots;
403	int vcpi;
404};
405
406/**
407 * struct drm_dp_mst_topology_mgr - DisplayPort MST manager
408 *
409 * This struct represents the toplevel displayport MST topology manager.
410 * There should be one instance of this for every MST capable DP connector
411 * on the GPU.
412 */
413struct drm_dp_mst_topology_mgr {
414	/**
415	 * @dev: device pointer for adding i2c devices etc.
416	 */
417	struct device *dev;
418	/**
419	 * @cbs: callbacks for connector addition and destruction.
420	 */
421	const struct drm_dp_mst_topology_cbs *cbs;
422	/**
423	 * @max_dpcd_transaction_bytes: maximum number of bytes to read/write
424	 * in one go.
425	 */
426	int max_dpcd_transaction_bytes;
427	/**
428	 * @aux: AUX channel for the DP MST connector this topolgy mgr is
429	 * controlling.
430	 */
431	struct drm_dp_aux *aux;
432	/**
433	 * @max_payloads: maximum number of payloads the GPU can generate.
434	 */
435	int max_payloads;
436	/**
437	 * @conn_base_id: DRM connector ID this mgr is connected to. Only used
438	 * to build the MST connector path value.
439	 */
440	int conn_base_id;
441
442	/**
443	 * @down_rep_recv: Message receiver state for down replies. This and
444	 * @up_req_recv are only ever access from the work item, which is
445	 * serialised.
446	 */
447	struct drm_dp_sideband_msg_rx down_rep_recv;
448	/**
449	 * @up_req_recv: Message receiver state for up requests. This and
450	 * @down_rep_recv are only ever access from the work item, which is
451	 * serialised.
452	 */
453	struct drm_dp_sideband_msg_rx up_req_recv;
454
455	/**
456	 * @lock: protects mst state, primary, dpcd.
457	 */
458	struct mutex lock;
459
460	/**
461	 * @mst_state: If this manager is enabled for an MST capable port. False
462	 * if no MST sink/branch devices is connected.
463	 */
464	bool mst_state;
465	/**
466	 * @mst_primary: Pointer to the primary/first branch device.
467	 */
468	struct drm_dp_mst_branch *mst_primary;
469
470	/**
471	 * @dpcd: Cache of DPCD for primary port.
472	 */
473	u8 dpcd[DP_RECEIVER_CAP_SIZE];
474	/**
475	 * @sink_count: Sink count from DEVICE_SERVICE_IRQ_VECTOR_ESI0.
476	 */
477	u8 sink_count;
478	/**
479	 * @pbn_div: PBN to slots divisor.
480	 */
481	int pbn_div;
482	/**
483	 * @total_slots: Total slots that can be allocated.
484	 */
485	int total_slots;
486	/**
487	 * @avail_slots: Still available slots that can be allocated.
488	 */
489	int avail_slots;
490	/**
491	 * @total_pbn: Total PBN count.
492	 */
493	int total_pbn;
494
495	/**
496	 * @qlock: protects @tx_msg_downq, the tx_slots in struct
497	 * &drm_dp_mst_branch and txmsg->state once they are queued
498	 */
499	struct mutex qlock;
500	/**
501	 * @tx_msg_downq: List of pending down replies.
502	 */
503	struct list_head tx_msg_downq;
504
505	/**
506	 * @payload_lock: Protect payload information.
507	 */
508	struct mutex payload_lock;
509	/**
510	 * @proposed_vcpis: Array of pointers for the new VCPI allocation. The
511	 * VCPI structure itself is embedded into the corresponding
512	 * &drm_dp_mst_port structure.
513	 */
514	struct drm_dp_vcpi **proposed_vcpis;
515	/**
516	 * @payloads: Array of payloads.
517	 */
518	struct drm_dp_payload *payloads;
519	/**
520	 * @payload_mask: Elements of @payloads actually in use. Since
521	 * reallocation of active outputs isn't possible gaps can be created by
522	 * disabling outputs out of order compared to how they've been enabled.
523	 */
524	unsigned long payload_mask;
525	/**
526	 * @vcpi_mask: Similar to @payload_mask, but for @proposed_vcpis.
527	 */
528	unsigned long vcpi_mask;
529
530	/**
531	 * @tx_waitq: Wait to queue stall for the tx worker.
532	 */
533	wait_queue_head_t tx_waitq;
534	/**
535	 * @work: Probe work.
536	 */
537	struct work_struct work;
538	/**
539	 * @tx_work: Sideband transmit worker. This can nest within the main
540	 * @work worker for each transaction @work launches.
541	 */
542	struct work_struct tx_work;
543
544	/**
545	 * @destroy_connector_list: List of to be destroyed connectors.
546	 */
547	struct list_head destroy_connector_list;
548	/**
549	 * @destroy_connector_lock: Protects @connector_list.
550	 */
551	struct mutex destroy_connector_lock;
552	/**
553	 * @destroy_connector_work: Work item to destroy connectors. Needed to
554	 * avoid locking inversion.
555	 */
556	struct work_struct destroy_connector_work;
557};
558
559int 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);
560
561void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr);
562
563
564int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state);
565
566
567int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled);
568
569
570enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
571
572bool drm_dp_mst_port_has_audio(struct drm_dp_mst_topology_mgr *mgr,
573					struct drm_dp_mst_port *port);
574struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
575
576
577int drm_dp_calc_pbn_mode(int clock, int bpp);
578
579
580bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots);
581
582int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
583
584
585void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
586
587
588void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
589				struct drm_dp_mst_port *port);
590
591
592int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
593			   int pbn);
594
595
596int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
597
598
599int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);
600
601int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr);
602
603void drm_dp_mst_dump_topology(struct seq_file *m,
604			      struct drm_dp_mst_topology_mgr *mgr);
605
606void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr);
607int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr);
608#endif