1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Thunderbolt link controller support
4 *
5 * Copyright (C) 2019, Intel Corporation
6 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
7 */
8
9 #include "tb.h"
10
11 /**
12 * tb_lc_read_uuid() - Read switch UUID from link controller common register
13 * @sw: Switch whose UUID is read
14 * @uuid: UUID is placed here
15 */
tb_lc_read_uuid(struct tb_switch * sw,u32 * uuid)16 int tb_lc_read_uuid(struct tb_switch *sw, u32 *uuid)
17 {
18 if (!sw->cap_lc)
19 return -EINVAL;
20 return tb_sw_read(sw, uuid, TB_CFG_SWITCH, sw->cap_lc + TB_LC_FUSE, 4);
21 }
22
read_lc_desc(struct tb_switch * sw,u32 * desc)23 static int read_lc_desc(struct tb_switch *sw, u32 *desc)
24 {
25 if (!sw->cap_lc)
26 return -EINVAL;
27 return tb_sw_read(sw, desc, TB_CFG_SWITCH, sw->cap_lc + TB_LC_DESC, 1);
28 }
29
find_port_lc_cap(struct tb_port * port)30 static int find_port_lc_cap(struct tb_port *port)
31 {
32 struct tb_switch *sw = port->sw;
33 int start, phys, ret, size;
34 u32 desc;
35
36 ret = read_lc_desc(sw, &desc);
37 if (ret)
38 return ret;
39
40 /* Start of port LC registers */
41 start = (desc & TB_LC_DESC_SIZE_MASK) >> TB_LC_DESC_SIZE_SHIFT;
42 size = (desc & TB_LC_DESC_PORT_SIZE_MASK) >> TB_LC_DESC_PORT_SIZE_SHIFT;
43 phys = tb_phy_port_from_link(port->port);
44
45 return sw->cap_lc + start + phys * size;
46 }
47
tb_lc_set_port_configured(struct tb_port * port,bool configured)48 static int tb_lc_set_port_configured(struct tb_port *port, bool configured)
49 {
50 bool upstream = tb_is_upstream_port(port);
51 struct tb_switch *sw = port->sw;
52 u32 ctrl, lane;
53 int cap, ret;
54
55 if (sw->generation < 2)
56 return 0;
57
58 cap = find_port_lc_cap(port);
59 if (cap < 0)
60 return cap;
61
62 ret = tb_sw_read(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1);
63 if (ret)
64 return ret;
65
66 /* Resolve correct lane */
67 if (port->port % 2)
68 lane = TB_LC_SX_CTRL_L1C;
69 else
70 lane = TB_LC_SX_CTRL_L2C;
71
72 if (configured) {
73 ctrl |= lane;
74 if (upstream)
75 ctrl |= TB_LC_SX_CTRL_UPSTREAM;
76 } else {
77 ctrl &= ~lane;
78 if (upstream)
79 ctrl &= ~TB_LC_SX_CTRL_UPSTREAM;
80 }
81
82 return tb_sw_write(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1);
83 }
84
85 /**
86 * tb_lc_configure_port() - Let LC know about configured port
87 * @port: Port that is set as configured
88 *
89 * Sets the port configured for power management purposes.
90 */
tb_lc_configure_port(struct tb_port * port)91 int tb_lc_configure_port(struct tb_port *port)
92 {
93 return tb_lc_set_port_configured(port, true);
94 }
95
96 /**
97 * tb_lc_unconfigure_port() - Let LC know about unconfigured port
98 * @port: Port that is set as configured
99 *
100 * Sets the port unconfigured for power management purposes.
101 */
tb_lc_unconfigure_port(struct tb_port * port)102 void tb_lc_unconfigure_port(struct tb_port *port)
103 {
104 tb_lc_set_port_configured(port, false);
105 }
106
tb_lc_set_xdomain_configured(struct tb_port * port,bool configure)107 static int tb_lc_set_xdomain_configured(struct tb_port *port, bool configure)
108 {
109 struct tb_switch *sw = port->sw;
110 u32 ctrl, lane;
111 int cap, ret;
112
113 if (sw->generation < 2)
114 return 0;
115
116 cap = find_port_lc_cap(port);
117 if (cap < 0)
118 return cap;
119
120 ret = tb_sw_read(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1);
121 if (ret)
122 return ret;
123
124 /* Resolve correct lane */
125 if (port->port % 2)
126 lane = TB_LC_SX_CTRL_L1D;
127 else
128 lane = TB_LC_SX_CTRL_L2D;
129
130 if (configure)
131 ctrl |= lane;
132 else
133 ctrl &= ~lane;
134
135 return tb_sw_write(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1);
136 }
137
138 /**
139 * tb_lc_configure_xdomain() - Inform LC that the link is XDomain
140 * @port: Switch downstream port connected to another host
141 *
142 * Sets the lane configured for XDomain accordingly so that the LC knows
143 * about this. Returns %0 in success and negative errno in failure.
144 */
tb_lc_configure_xdomain(struct tb_port * port)145 int tb_lc_configure_xdomain(struct tb_port *port)
146 {
147 return tb_lc_set_xdomain_configured(port, true);
148 }
149
150 /**
151 * tb_lc_unconfigure_xdomain() - Unconfigure XDomain from port
152 * @port: Switch downstream port that was connected to another host
153 *
154 * Unsets the lane XDomain configuration.
155 */
tb_lc_unconfigure_xdomain(struct tb_port * port)156 void tb_lc_unconfigure_xdomain(struct tb_port *port)
157 {
158 tb_lc_set_xdomain_configured(port, false);
159 }
160
161 /**
162 * tb_lc_start_lane_initialization() - Start lane initialization
163 * @port: Device router lane 0 adapter
164 *
165 * Starts lane initialization for @port after the router resumed from
166 * sleep. Should be called for those downstream lane adapters that were
167 * not connected (tb_lc_configure_port() was not called) before sleep.
168 *
169 * Returns %0 in success and negative errno in case of failure.
170 */
tb_lc_start_lane_initialization(struct tb_port * port)171 int tb_lc_start_lane_initialization(struct tb_port *port)
172 {
173 struct tb_switch *sw = port->sw;
174 int ret, cap;
175 u32 ctrl;
176
177 if (!tb_route(sw))
178 return 0;
179
180 if (sw->generation < 2)
181 return 0;
182
183 cap = find_port_lc_cap(port);
184 if (cap < 0)
185 return cap;
186
187 ret = tb_sw_read(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1);
188 if (ret)
189 return ret;
190
191 ctrl |= TB_LC_SX_CTRL_SLI;
192
193 return tb_sw_write(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1);
194 }
195
tb_lc_set_wake_one(struct tb_switch * sw,unsigned int offset,unsigned int flags)196 static int tb_lc_set_wake_one(struct tb_switch *sw, unsigned int offset,
197 unsigned int flags)
198 {
199 u32 ctrl;
200 int ret;
201
202 /*
203 * Enable wake on PCIe and USB4 (wake coming from another
204 * router).
205 */
206 ret = tb_sw_read(sw, &ctrl, TB_CFG_SWITCH,
207 offset + TB_LC_SX_CTRL, 1);
208 if (ret)
209 return ret;
210
211 ctrl &= ~(TB_LC_SX_CTRL_WOC | TB_LC_SX_CTRL_WOD | TB_LC_SX_CTRL_WODPC |
212 TB_LC_SX_CTRL_WODPD | TB_LC_SX_CTRL_WOP | TB_LC_SX_CTRL_WOU4);
213
214 if (flags & TB_WAKE_ON_CONNECT)
215 ctrl |= TB_LC_SX_CTRL_WOC | TB_LC_SX_CTRL_WOD;
216 if (flags & TB_WAKE_ON_USB4)
217 ctrl |= TB_LC_SX_CTRL_WOU4;
218 if (flags & TB_WAKE_ON_PCIE)
219 ctrl |= TB_LC_SX_CTRL_WOP;
220 if (flags & TB_WAKE_ON_DP)
221 ctrl |= TB_LC_SX_CTRL_WODPC | TB_LC_SX_CTRL_WODPD;
222
223 return tb_sw_write(sw, &ctrl, TB_CFG_SWITCH, offset + TB_LC_SX_CTRL, 1);
224 }
225
226 /**
227 * tb_lc_set_wake() - Enable/disable wake
228 * @sw: Switch whose wakes to configure
229 * @flags: Wakeup flags (%0 to disable)
230 *
231 * For each LC sets wake bits accordingly.
232 */
tb_lc_set_wake(struct tb_switch * sw,unsigned int flags)233 int tb_lc_set_wake(struct tb_switch *sw, unsigned int flags)
234 {
235 int start, size, nlc, ret, i;
236 u32 desc;
237
238 if (sw->generation < 2)
239 return 0;
240
241 if (!tb_route(sw))
242 return 0;
243
244 ret = read_lc_desc(sw, &desc);
245 if (ret)
246 return ret;
247
248 /* Figure out number of link controllers */
249 nlc = desc & TB_LC_DESC_NLC_MASK;
250 start = (desc & TB_LC_DESC_SIZE_MASK) >> TB_LC_DESC_SIZE_SHIFT;
251 size = (desc & TB_LC_DESC_PORT_SIZE_MASK) >> TB_LC_DESC_PORT_SIZE_SHIFT;
252
253 /* For each link controller set sleep bit */
254 for (i = 0; i < nlc; i++) {
255 unsigned int offset = sw->cap_lc + start + i * size;
256
257 ret = tb_lc_set_wake_one(sw, offset, flags);
258 if (ret)
259 return ret;
260 }
261
262 return 0;
263 }
264
265 /**
266 * tb_lc_set_sleep() - Inform LC that the switch is going to sleep
267 * @sw: Switch to set sleep
268 *
269 * Let the switch link controllers know that the switch is going to
270 * sleep.
271 */
tb_lc_set_sleep(struct tb_switch * sw)272 int tb_lc_set_sleep(struct tb_switch *sw)
273 {
274 int start, size, nlc, ret, i;
275 u32 desc;
276
277 if (sw->generation < 2)
278 return 0;
279
280 ret = read_lc_desc(sw, &desc);
281 if (ret)
282 return ret;
283
284 /* Figure out number of link controllers */
285 nlc = desc & TB_LC_DESC_NLC_MASK;
286 start = (desc & TB_LC_DESC_SIZE_MASK) >> TB_LC_DESC_SIZE_SHIFT;
287 size = (desc & TB_LC_DESC_PORT_SIZE_MASK) >> TB_LC_DESC_PORT_SIZE_SHIFT;
288
289 /* For each link controller set sleep bit */
290 for (i = 0; i < nlc; i++) {
291 unsigned int offset = sw->cap_lc + start + i * size;
292 u32 ctrl;
293
294 ret = tb_sw_read(sw, &ctrl, TB_CFG_SWITCH,
295 offset + TB_LC_SX_CTRL, 1);
296 if (ret)
297 return ret;
298
299 ctrl |= TB_LC_SX_CTRL_SLP;
300 ret = tb_sw_write(sw, &ctrl, TB_CFG_SWITCH,
301 offset + TB_LC_SX_CTRL, 1);
302 if (ret)
303 return ret;
304 }
305
306 return 0;
307 }
308
309 /**
310 * tb_lc_lane_bonding_possible() - Is lane bonding possible towards switch
311 * @sw: Switch to check
312 *
313 * Checks whether conditions for lane bonding from parent to @sw are
314 * possible.
315 */
tb_lc_lane_bonding_possible(struct tb_switch * sw)316 bool tb_lc_lane_bonding_possible(struct tb_switch *sw)
317 {
318 struct tb_port *up;
319 int cap, ret;
320 u32 val;
321
322 if (sw->generation < 2)
323 return false;
324
325 up = tb_upstream_port(sw);
326 cap = find_port_lc_cap(up);
327 if (cap < 0)
328 return false;
329
330 ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, cap + TB_LC_PORT_ATTR, 1);
331 if (ret)
332 return false;
333
334 return !!(val & TB_LC_PORT_ATTR_BE);
335 }
336
tb_lc_dp_sink_from_port(const struct tb_switch * sw,struct tb_port * in)337 static int tb_lc_dp_sink_from_port(const struct tb_switch *sw,
338 struct tb_port *in)
339 {
340 struct tb_port *port;
341
342 /* The first DP IN port is sink 0 and second is sink 1 */
343 tb_switch_for_each_port(sw, port) {
344 if (tb_port_is_dpin(port))
345 return in != port;
346 }
347
348 return -EINVAL;
349 }
350
tb_lc_dp_sink_available(struct tb_switch * sw,int sink)351 static int tb_lc_dp_sink_available(struct tb_switch *sw, int sink)
352 {
353 u32 val, alloc;
354 int ret;
355
356 ret = tb_sw_read(sw, &val, TB_CFG_SWITCH,
357 sw->cap_lc + TB_LC_SNK_ALLOCATION, 1);
358 if (ret)
359 return ret;
360
361 /*
362 * Sink is available for CM/SW to use if the allocation valie is
363 * either 0 or 1.
364 */
365 if (!sink) {
366 alloc = val & TB_LC_SNK_ALLOCATION_SNK0_MASK;
367 if (!alloc || alloc == TB_LC_SNK_ALLOCATION_SNK0_CM)
368 return 0;
369 } else {
370 alloc = (val & TB_LC_SNK_ALLOCATION_SNK1_MASK) >>
371 TB_LC_SNK_ALLOCATION_SNK1_SHIFT;
372 if (!alloc || alloc == TB_LC_SNK_ALLOCATION_SNK1_CM)
373 return 0;
374 }
375
376 return -EBUSY;
377 }
378
379 /**
380 * tb_lc_dp_sink_query() - Is DP sink available for DP IN port
381 * @sw: Switch whose DP sink is queried
382 * @in: DP IN port to check
383 *
384 * Queries through LC SNK_ALLOCATION registers whether DP sink is available
385 * for the given DP IN port or not.
386 */
tb_lc_dp_sink_query(struct tb_switch * sw,struct tb_port * in)387 bool tb_lc_dp_sink_query(struct tb_switch *sw, struct tb_port *in)
388 {
389 int sink;
390
391 /*
392 * For older generations sink is always available as there is no
393 * allocation mechanism.
394 */
395 if (sw->generation < 3)
396 return true;
397
398 sink = tb_lc_dp_sink_from_port(sw, in);
399 if (sink < 0)
400 return false;
401
402 return !tb_lc_dp_sink_available(sw, sink);
403 }
404
405 /**
406 * tb_lc_dp_sink_alloc() - Allocate DP sink
407 * @sw: Switch whose DP sink is allocated
408 * @in: DP IN port the DP sink is allocated for
409 *
410 * Allocate DP sink for @in via LC SNK_ALLOCATION registers. If the
411 * resource is available and allocation is successful returns %0. In all
412 * other cases returs negative errno. In particular %-EBUSY is returned if
413 * the resource was not available.
414 */
tb_lc_dp_sink_alloc(struct tb_switch * sw,struct tb_port * in)415 int tb_lc_dp_sink_alloc(struct tb_switch *sw, struct tb_port *in)
416 {
417 int ret, sink;
418 u32 val;
419
420 if (sw->generation < 3)
421 return 0;
422
423 sink = tb_lc_dp_sink_from_port(sw, in);
424 if (sink < 0)
425 return sink;
426
427 ret = tb_lc_dp_sink_available(sw, sink);
428 if (ret)
429 return ret;
430
431 ret = tb_sw_read(sw, &val, TB_CFG_SWITCH,
432 sw->cap_lc + TB_LC_SNK_ALLOCATION, 1);
433 if (ret)
434 return ret;
435
436 if (!sink) {
437 val &= ~TB_LC_SNK_ALLOCATION_SNK0_MASK;
438 val |= TB_LC_SNK_ALLOCATION_SNK0_CM;
439 } else {
440 val &= ~TB_LC_SNK_ALLOCATION_SNK1_MASK;
441 val |= TB_LC_SNK_ALLOCATION_SNK1_CM <<
442 TB_LC_SNK_ALLOCATION_SNK1_SHIFT;
443 }
444
445 ret = tb_sw_write(sw, &val, TB_CFG_SWITCH,
446 sw->cap_lc + TB_LC_SNK_ALLOCATION, 1);
447
448 if (ret)
449 return ret;
450
451 tb_port_dbg(in, "sink %d allocated\n", sink);
452 return 0;
453 }
454
455 /**
456 * tb_lc_dp_sink_dealloc() - De-allocate DP sink
457 * @sw: Switch whose DP sink is de-allocated
458 * @in: DP IN port whose DP sink is de-allocated
459 *
460 * De-allocate DP sink from @in using LC SNK_ALLOCATION registers.
461 */
tb_lc_dp_sink_dealloc(struct tb_switch * sw,struct tb_port * in)462 int tb_lc_dp_sink_dealloc(struct tb_switch *sw, struct tb_port *in)
463 {
464 int ret, sink;
465 u32 val;
466
467 if (sw->generation < 3)
468 return 0;
469
470 sink = tb_lc_dp_sink_from_port(sw, in);
471 if (sink < 0)
472 return sink;
473
474 /* Needs to be owned by CM/SW */
475 ret = tb_lc_dp_sink_available(sw, sink);
476 if (ret)
477 return ret;
478
479 ret = tb_sw_read(sw, &val, TB_CFG_SWITCH,
480 sw->cap_lc + TB_LC_SNK_ALLOCATION, 1);
481 if (ret)
482 return ret;
483
484 if (!sink)
485 val &= ~TB_LC_SNK_ALLOCATION_SNK0_MASK;
486 else
487 val &= ~TB_LC_SNK_ALLOCATION_SNK1_MASK;
488
489 ret = tb_sw_write(sw, &val, TB_CFG_SWITCH,
490 sw->cap_lc + TB_LC_SNK_ALLOCATION, 1);
491 if (ret)
492 return ret;
493
494 tb_port_dbg(in, "sink %d de-allocated\n", sink);
495 return 0;
496 }
497
498 /**
499 * tb_lc_force_power() - Forces LC to be powered on
500 * @sw: Thunderbolt switch
501 *
502 * This is useful to let authentication cycle pass even without
503 * a Thunderbolt link present.
504 */
tb_lc_force_power(struct tb_switch * sw)505 int tb_lc_force_power(struct tb_switch *sw)
506 {
507 u32 in = 0xffff;
508
509 return tb_sw_write(sw, &in, TB_CFG_SWITCH, TB_LC_POWER, 1);
510 }
511