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	struct edid *cached_edid; /* for DP logical ports - make tiling work */
91};
92
93/**
94 * struct drm_dp_mst_branch - MST branch device.
95 * @kref: reference count for this port.
96 * @rad: Relative Address to talk to this branch device.
97 * @lct: Link count total to talk to this branch device.
98 * @num_ports: number of ports on the branch.
99 * @msg_slots: one bit per transmitted msg slot.
100 * @ports: linked list of ports on this branch.
101 * @port_parent: pointer to the port parent, NULL if toplevel.
102 * @mgr: topology manager for this branch device.
103 * @tx_slots: transmission slots for this device.
104 * @last_seqno: last sequence number used to talk to this.
105 * @link_address_sent: if a link address message has been sent to this device yet.
106 * @guid: guid for DP 1.2 branch device. port under this branch can be
107 * identified by port #.
108 *
109 * This structure represents an MST branch device, there is one
110 * primary branch device at the root, along with any other branches connected
111 * to downstream port of parent branches.
112 */
113struct drm_dp_mst_branch {
114	struct kref kref;
115	u8 rad[8];
116	u8 lct;
117	int num_ports;
118
119	int msg_slots;
120	struct list_head ports;
121
122	/* list of tx ops queue for this port */
123	struct drm_dp_mst_port *port_parent;
124	struct drm_dp_mst_topology_mgr *mgr;
125
126	/* slots are protected by mstb->mgr->qlock */
127	struct drm_dp_sideband_msg_tx *tx_slots[2];
128	int last_seqno;
129	bool link_address_sent;
130
131	/* global unique identifier to identify branch devices */
132	u8 guid[16];
133};
134
135
136/* sideband msg header - not bit struct */
137struct drm_dp_sideband_msg_hdr {
138	u8 lct;
139	u8 lcr;
140	u8 rad[8];
141	bool broadcast;
142	bool path_msg;
143	u8 msg_len;
144	bool somt;
145	bool eomt;
146	bool seqno;
147};
148
149struct drm_dp_nak_reply {
150	u8 guid[16];
151	u8 reason;
152	u8 nak_data;
153};
154
155struct drm_dp_link_address_ack_reply {
156	u8 guid[16];
157	u8 nports;
158	struct drm_dp_link_addr_reply_port {
159		bool input_port;
160		u8 peer_device_type;
161		u8 port_number;
162		bool mcs;
163		bool ddps;
164		bool legacy_device_plug_status;
165		u8 dpcd_revision;
166		u8 peer_guid[16];
167		u8 num_sdp_streams;
168		u8 num_sdp_stream_sinks;
169	} ports[16];
170};
171
172struct drm_dp_remote_dpcd_read_ack_reply {
173	u8 port_number;
174	u8 num_bytes;
175	u8 bytes[255];
176};
177
178struct drm_dp_remote_dpcd_write_ack_reply {
179	u8 port_number;
180};
181
182struct drm_dp_remote_dpcd_write_nak_reply {
183	u8 port_number;
184	u8 reason;
185	u8 bytes_written_before_failure;
186};
187
188struct drm_dp_remote_i2c_read_ack_reply {
189	u8 port_number;
190	u8 num_bytes;
191	u8 bytes[255];
192};
193
194struct drm_dp_remote_i2c_read_nak_reply {
195	u8 port_number;
196	u8 nak_reason;
197	u8 i2c_nak_transaction;
198};
199
200struct drm_dp_remote_i2c_write_ack_reply {
201	u8 port_number;
202};
203
204
205struct drm_dp_sideband_msg_rx {
206	u8 chunk[48];
207	u8 msg[256];
208	u8 curchunk_len;
209	u8 curchunk_idx; /* chunk we are parsing now */
210	u8 curchunk_hdrlen;
211	u8 curlen; /* total length of the msg */
212	bool have_somt;
213	bool have_eomt;
214	struct drm_dp_sideband_msg_hdr initial_hdr;
215};
216
217
218struct drm_dp_allocate_payload {
219	u8 port_number;
220	u8 number_sdp_streams;
221	u8 vcpi;
222	u16 pbn;
223	u8 sdp_stream_sink[8];
224};
225
226struct drm_dp_allocate_payload_ack_reply {
227	u8 port_number;
228	u8 vcpi;
229	u16 allocated_pbn;
230};
231
232struct drm_dp_connection_status_notify {
233	u8 guid[16];
234	u8 port_number;
235	bool legacy_device_plug_status;
236	bool displayport_device_plug_status;
237	bool message_capability_status;
238	bool input_port;
239	u8 peer_device_type;
240};
241
242struct drm_dp_remote_dpcd_read {
243	u8 port_number;
244	u32 dpcd_address;
245	u8 num_bytes;
246};
247
248struct drm_dp_remote_dpcd_write {
249	u8 port_number;
250	u32 dpcd_address;
251	u8 num_bytes;
252	u8 *bytes;
253};
254
255#define DP_REMOTE_I2C_READ_MAX_TRANSACTIONS 4
256struct drm_dp_remote_i2c_read {
257	u8 num_transactions;
258	u8 port_number;
259	struct {
260		u8 i2c_dev_id;
261		u8 num_bytes;
262		u8 *bytes;
263		u8 no_stop_bit;
264		u8 i2c_transaction_delay;
265	} transactions[DP_REMOTE_I2C_READ_MAX_TRANSACTIONS];
266	u8 read_i2c_device_id;
267	u8 num_bytes_read;
268};
269
270struct drm_dp_remote_i2c_write {
271	u8 port_number;
272	u8 write_i2c_device_id;
273	u8 num_bytes;
274	u8 *bytes;
275};
276
277/* this covers ENUM_RESOURCES, POWER_DOWN_PHY, POWER_UP_PHY */
278struct drm_dp_port_number_req {
279	u8 port_number;
280};
281
282struct drm_dp_enum_path_resources_ack_reply {
283	u8 port_number;
284	u16 full_payload_bw_number;
285	u16 avail_payload_bw_number;
286};
287
288/* covers POWER_DOWN_PHY, POWER_UP_PHY */
289struct drm_dp_port_number_rep {
290	u8 port_number;
291};
292
293struct drm_dp_query_payload {
294	u8 port_number;
295	u8 vcpi;
296};
297
298struct drm_dp_resource_status_notify {
299	u8 port_number;
300	u8 guid[16];
301	u16 available_pbn;
302};
303
304struct drm_dp_query_payload_ack_reply {
305	u8 port_number;
306	u8 allocated_pbn;
307};
308
309struct drm_dp_sideband_msg_req_body {
310	u8 req_type;
311	union ack_req {
312		struct drm_dp_connection_status_notify conn_stat;
313		struct drm_dp_port_number_req port_num;
314		struct drm_dp_resource_status_notify resource_stat;
315
316		struct drm_dp_query_payload query_payload;
317		struct drm_dp_allocate_payload allocate_payload;
318
319		struct drm_dp_remote_dpcd_read dpcd_read;
320		struct drm_dp_remote_dpcd_write dpcd_write;
321
322		struct drm_dp_remote_i2c_read i2c_read;
323		struct drm_dp_remote_i2c_write i2c_write;
324	} u;
325};
326
327struct drm_dp_sideband_msg_reply_body {
328	u8 reply_type;
329	u8 req_type;
330	union ack_replies {
331		struct drm_dp_nak_reply nak;
332		struct drm_dp_link_address_ack_reply link_addr;
333		struct drm_dp_port_number_rep port_number;
334
335		struct drm_dp_enum_path_resources_ack_reply path_resources;
336		struct drm_dp_allocate_payload_ack_reply allocate_payload;
337		struct drm_dp_query_payload_ack_reply query_payload;
338
339		struct drm_dp_remote_dpcd_read_ack_reply remote_dpcd_read_ack;
340		struct drm_dp_remote_dpcd_write_ack_reply remote_dpcd_write_ack;
341		struct drm_dp_remote_dpcd_write_nak_reply remote_dpcd_write_nack;
342
343		struct drm_dp_remote_i2c_read_ack_reply remote_i2c_read_ack;
344		struct drm_dp_remote_i2c_read_nak_reply remote_i2c_read_nack;
345		struct drm_dp_remote_i2c_write_ack_reply remote_i2c_write_ack;
346	} u;
347};
348
349/* msg is queued to be put into a slot */
350#define DRM_DP_SIDEBAND_TX_QUEUED 0
351/* msg has started transmitting on a slot - still on msgq */
352#define DRM_DP_SIDEBAND_TX_START_SEND 1
353/* msg has finished transmitting on a slot - removed from msgq only in slot */
354#define DRM_DP_SIDEBAND_TX_SENT 2
355/* msg has received a response - removed from slot */
356#define DRM_DP_SIDEBAND_TX_RX 3
357#define DRM_DP_SIDEBAND_TX_TIMEOUT 4
358
359struct drm_dp_sideband_msg_tx {
360	u8 msg[256];
361	u8 chunk[48];
362	u8 cur_offset;
363	u8 cur_len;
364	struct drm_dp_mst_branch *dst;
365	struct list_head next;
366	int seqno;
367	int state;
368	bool path_msg;
369	struct drm_dp_sideband_msg_reply_body reply;
370};
371
372/* sideband msg handler */
373struct drm_dp_mst_topology_mgr;
374struct drm_dp_mst_topology_cbs {
375	/* create a connector for a port */
376	struct drm_connector *(*add_connector)(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, const char *path);
377	void (*destroy_connector)(struct drm_dp_mst_topology_mgr *mgr,
378				  struct drm_connector *connector);
379	void (*hotplug)(struct drm_dp_mst_topology_mgr *mgr);
380
381};
382
383#define DP_MAX_PAYLOAD (sizeof(unsigned long) * 8)
384
385#define DP_PAYLOAD_LOCAL 1
386#define DP_PAYLOAD_REMOTE 2
387#define DP_PAYLOAD_DELETE_LOCAL 3
388
389struct drm_dp_payload {
390	int payload_state;
391	int start_slot;
392	int num_slots;
393	int vcpi;
394};
395
396/**
397 * struct drm_dp_mst_topology_mgr - DisplayPort MST manager
398 * @dev: device pointer for adding i2c devices etc.
399 * @cbs: callbacks for connector addition and destruction.
400 * @max_dpcd_transaction_bytes - maximum number of bytes to read/write in one go.
401 * @aux: aux channel for the DP connector.
402 * @max_payloads: maximum number of payloads the GPU can generate.
403 * @conn_base_id: DRM connector ID this mgr is connected to.
404 * @down_rep_recv: msg receiver state for down replies.
405 * @up_req_recv: msg receiver state for up requests.
406 * @lock: protects mst state, primary, dpcd.
407 * @mst_state: if this manager is enabled for an MST capable port.
408 * @mst_primary: pointer to the primary branch device.
409 * @dpcd: cache of DPCD for primary port.
410 * @pbn_div: PBN to slots divisor.
411 *
412 * This struct represents the toplevel displayport MST topology manager.
413 * There should be one instance of this for every MST capable DP connector
414 * on the GPU.
415 */
416struct drm_dp_mst_topology_mgr {
417
418	struct device *dev;
419	struct drm_dp_mst_topology_cbs *cbs;
420	int max_dpcd_transaction_bytes;
421	struct drm_dp_aux *aux; /* auxch for this topology mgr to use */
422	int max_payloads;
423	int conn_base_id;
424
425	/* only ever accessed from the workqueue - which should be serialised */
426	struct drm_dp_sideband_msg_rx down_rep_recv;
427	struct drm_dp_sideband_msg_rx up_req_recv;
428
429	/* pointer to info about the initial MST device */
430	struct mutex lock; /* protects mst_state + primary + dpcd */
431
432	bool mst_state;
433	struct drm_dp_mst_branch *mst_primary;
434
435	u8 dpcd[DP_RECEIVER_CAP_SIZE];
436	u8 sink_count;
437	int pbn_div;
438	int total_slots;
439	int avail_slots;
440	int total_pbn;
441
442	/* messages to be transmitted */
443	/* qlock protects the upq/downq and in_progress,
444	   the mstb tx_slots and txmsg->state once they are queued */
445	struct mutex qlock;
446	struct list_head tx_msg_downq;
447	bool tx_down_in_progress;
448
449	/* payload info + lock for it */
450	struct mutex payload_lock;
451	struct drm_dp_vcpi **proposed_vcpis;
452	struct drm_dp_payload *payloads;
453	unsigned long payload_mask;
454	unsigned long vcpi_mask;
455
456	wait_queue_head_t tx_waitq;
457	struct work_struct work;
458
459	struct work_struct tx_work;
460
461	struct list_head destroy_connector_list;
462	struct mutex destroy_connector_lock;
463	struct work_struct destroy_connector_work;
464};
465
466int 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);
467
468void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr);
469
470
471int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state);
472
473
474int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled);
475
476
477enum 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);
478
479struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
480
481
482int drm_dp_calc_pbn_mode(int clock, int bpp);
483
484
485bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots);
486
487int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
488
489
490void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
491
492
493void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
494				struct drm_dp_mst_port *port);
495
496
497int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
498			   int pbn);
499
500
501int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
502
503
504int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);
505
506int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr);
507
508void drm_dp_mst_dump_topology(struct seq_file *m,
509			      struct drm_dp_mst_topology_mgr *mgr);
510
511void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr);
512int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr);
513#endif
514