Commit | Line | Data |
---|---|---|
d6cc51cd AN |
1 | /* |
2 | * Thunderbolt Cactus Ridge driver - bus logic (NHI independent) | |
3 | * | |
4 | * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com> | |
5 | */ | |
6 | ||
7 | #include <linux/slab.h> | |
8 | #include <linux/errno.h> | |
9 | #include <linux/delay.h> | |
10 | ||
11 | #include "tb.h" | |
7adf6097 | 12 | #include "tb_regs.h" |
3364f0c1 | 13 | #include "tunnel_pci.h" |
d6cc51cd | 14 | |
9da672a4 AN |
15 | |
16 | /* enumeration & hot plug handling */ | |
17 | ||
18 | ||
19 | static void tb_scan_port(struct tb_port *port); | |
20 | ||
21 | /** | |
22 | * tb_scan_switch() - scan for and initialize downstream switches | |
23 | */ | |
24 | static void tb_scan_switch(struct tb_switch *sw) | |
25 | { | |
26 | int i; | |
27 | for (i = 1; i <= sw->config.max_port_number; i++) | |
28 | tb_scan_port(&sw->ports[i]); | |
29 | } | |
30 | ||
31 | /** | |
32 | * tb_scan_port() - check for and initialize switches below port | |
33 | */ | |
34 | static void tb_scan_port(struct tb_port *port) | |
35 | { | |
36 | struct tb_switch *sw; | |
37 | if (tb_is_upstream_port(port)) | |
38 | return; | |
39 | if (port->config.type != TB_TYPE_PORT) | |
40 | return; | |
343fcb8c AN |
41 | if (port->dual_link_port && port->link_nr) |
42 | return; /* | |
43 | * Downstream switch is reachable through two ports. | |
44 | * Only scan on the primary port (link_nr == 0). | |
45 | */ | |
9da672a4 AN |
46 | if (tb_wait_for_port(port, false) <= 0) |
47 | return; | |
48 | if (port->remote) { | |
49 | tb_port_WARN(port, "port already has a remote!\n"); | |
50 | return; | |
51 | } | |
52 | sw = tb_switch_alloc(port->sw->tb, tb_downstream_route(port)); | |
53 | if (!sw) | |
54 | return; | |
55 | port->remote = tb_upstream_port(sw); | |
56 | tb_upstream_port(sw)->remote = port; | |
57 | tb_scan_switch(sw); | |
58 | } | |
59 | ||
3364f0c1 AN |
60 | /** |
61 | * tb_free_invalid_tunnels() - destroy tunnels of devices that have gone away | |
62 | */ | |
63 | static void tb_free_invalid_tunnels(struct tb *tb) | |
64 | { | |
65 | struct tb_pci_tunnel *tunnel; | |
66 | struct tb_pci_tunnel *n; | |
67 | list_for_each_entry_safe(tunnel, n, &tb->tunnel_list, list) | |
68 | { | |
69 | if (tb_pci_is_invalid(tunnel)) { | |
70 | tb_pci_deactivate(tunnel); | |
71 | tb_pci_free(tunnel); | |
72 | } | |
73 | } | |
74 | } | |
75 | ||
23dd5bb4 AN |
76 | /** |
77 | * tb_free_unplugged_children() - traverse hierarchy and free unplugged switches | |
78 | */ | |
79 | static void tb_free_unplugged_children(struct tb_switch *sw) | |
80 | { | |
81 | int i; | |
82 | for (i = 1; i <= sw->config.max_port_number; i++) { | |
83 | struct tb_port *port = &sw->ports[i]; | |
84 | if (tb_is_upstream_port(port)) | |
85 | continue; | |
86 | if (!port->remote) | |
87 | continue; | |
88 | if (port->remote->sw->is_unplugged) { | |
89 | tb_switch_free(port->remote->sw); | |
90 | port->remote = NULL; | |
91 | } else { | |
92 | tb_free_unplugged_children(port->remote->sw); | |
93 | } | |
94 | } | |
95 | } | |
96 | ||
97 | ||
3364f0c1 AN |
98 | /** |
99 | * find_pci_up_port() - return the first PCIe up port on @sw or NULL | |
100 | */ | |
101 | static struct tb_port *tb_find_pci_up_port(struct tb_switch *sw) | |
102 | { | |
103 | int i; | |
104 | for (i = 1; i <= sw->config.max_port_number; i++) | |
105 | if (sw->ports[i].config.type == TB_TYPE_PCIE_UP) | |
106 | return &sw->ports[i]; | |
107 | return NULL; | |
108 | } | |
109 | ||
110 | /** | |
111 | * find_unused_down_port() - return the first inactive PCIe down port on @sw | |
112 | */ | |
113 | static struct tb_port *tb_find_unused_down_port(struct tb_switch *sw) | |
114 | { | |
115 | int i; | |
116 | int cap; | |
117 | int res; | |
118 | int data; | |
119 | for (i = 1; i <= sw->config.max_port_number; i++) { | |
120 | if (tb_is_upstream_port(&sw->ports[i])) | |
121 | continue; | |
122 | if (sw->ports[i].config.type != TB_TYPE_PCIE_DOWN) | |
123 | continue; | |
124 | cap = tb_find_cap(&sw->ports[i], TB_CFG_PORT, TB_CAP_PCIE); | |
125 | if (cap <= 0) | |
126 | continue; | |
127 | res = tb_port_read(&sw->ports[i], &data, TB_CFG_PORT, cap, 1); | |
128 | if (res < 0) | |
129 | continue; | |
130 | if (data & 0x80000000) | |
131 | continue; | |
132 | return &sw->ports[i]; | |
133 | } | |
134 | return NULL; | |
135 | } | |
136 | ||
137 | /** | |
138 | * tb_activate_pcie_devices() - scan for and activate PCIe devices | |
139 | * | |
140 | * This method is somewhat ad hoc. For now it only supports one device | |
141 | * per port and only devices at depth 1. | |
142 | */ | |
143 | static void tb_activate_pcie_devices(struct tb *tb) | |
144 | { | |
145 | int i; | |
146 | int cap; | |
147 | u32 data; | |
148 | struct tb_switch *sw; | |
149 | struct tb_port *up_port; | |
150 | struct tb_port *down_port; | |
151 | struct tb_pci_tunnel *tunnel; | |
152 | /* scan for pcie devices at depth 1*/ | |
153 | for (i = 1; i <= tb->root_switch->config.max_port_number; i++) { | |
154 | if (tb_is_upstream_port(&tb->root_switch->ports[i])) | |
155 | continue; | |
156 | if (tb->root_switch->ports[i].config.type != TB_TYPE_PORT) | |
157 | continue; | |
158 | if (!tb->root_switch->ports[i].remote) | |
159 | continue; | |
160 | sw = tb->root_switch->ports[i].remote->sw; | |
161 | up_port = tb_find_pci_up_port(sw); | |
162 | if (!up_port) { | |
163 | tb_sw_info(sw, "no PCIe devices found, aborting\n"); | |
164 | continue; | |
165 | } | |
166 | ||
167 | /* check whether port is already activated */ | |
168 | cap = tb_find_cap(up_port, TB_CFG_PORT, TB_CAP_PCIE); | |
169 | if (cap <= 0) | |
170 | continue; | |
171 | if (tb_port_read(up_port, &data, TB_CFG_PORT, cap, 1)) | |
172 | continue; | |
173 | if (data & 0x80000000) { | |
174 | tb_port_info(up_port, | |
175 | "PCIe port already activated, aborting\n"); | |
176 | continue; | |
177 | } | |
178 | ||
179 | down_port = tb_find_unused_down_port(tb->root_switch); | |
180 | if (!down_port) { | |
181 | tb_port_info(up_port, | |
182 | "All PCIe down ports are occupied, aborting\n"); | |
183 | continue; | |
184 | } | |
185 | tunnel = tb_pci_alloc(tb, up_port, down_port); | |
186 | if (!tunnel) { | |
187 | tb_port_info(up_port, | |
188 | "PCIe tunnel allocation failed, aborting\n"); | |
189 | continue; | |
190 | } | |
191 | ||
192 | if (tb_pci_activate(tunnel)) { | |
193 | tb_port_info(up_port, | |
194 | "PCIe tunnel activation failed, aborting\n"); | |
195 | tb_pci_free(tunnel); | |
196 | } | |
197 | ||
198 | } | |
199 | } | |
9da672a4 | 200 | |
d6cc51cd AN |
201 | /* hotplug handling */ |
202 | ||
203 | struct tb_hotplug_event { | |
204 | struct work_struct work; | |
205 | struct tb *tb; | |
206 | u64 route; | |
207 | u8 port; | |
208 | bool unplug; | |
209 | }; | |
210 | ||
211 | /** | |
212 | * tb_handle_hotplug() - handle hotplug event | |
213 | * | |
214 | * Executes on tb->wq. | |
215 | */ | |
216 | static void tb_handle_hotplug(struct work_struct *work) | |
217 | { | |
218 | struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work); | |
219 | struct tb *tb = ev->tb; | |
053596d9 AN |
220 | struct tb_switch *sw; |
221 | struct tb_port *port; | |
d6cc51cd AN |
222 | mutex_lock(&tb->lock); |
223 | if (!tb->hotplug_active) | |
224 | goto out; /* during init, suspend or shutdown */ | |
225 | ||
053596d9 AN |
226 | sw = get_switch_at_route(tb->root_switch, ev->route); |
227 | if (!sw) { | |
228 | tb_warn(tb, | |
229 | "hotplug event from non existent switch %llx:%x (unplug: %d)\n", | |
230 | ev->route, ev->port, ev->unplug); | |
231 | goto out; | |
232 | } | |
233 | if (ev->port > sw->config.max_port_number) { | |
234 | tb_warn(tb, | |
235 | "hotplug event from non existent port %llx:%x (unplug: %d)\n", | |
236 | ev->route, ev->port, ev->unplug); | |
237 | goto out; | |
238 | } | |
239 | port = &sw->ports[ev->port]; | |
240 | if (tb_is_upstream_port(port)) { | |
241 | tb_warn(tb, | |
242 | "hotplug event for upstream port %llx:%x (unplug: %d)\n", | |
243 | ev->route, ev->port, ev->unplug); | |
244 | goto out; | |
245 | } | |
246 | if (ev->unplug) { | |
247 | if (port->remote) { | |
248 | tb_port_info(port, "unplugged\n"); | |
249 | tb_sw_set_unpplugged(port->remote->sw); | |
3364f0c1 | 250 | tb_free_invalid_tunnels(tb); |
053596d9 AN |
251 | tb_switch_free(port->remote->sw); |
252 | port->remote = NULL; | |
253 | } else { | |
254 | tb_port_info(port, | |
255 | "got unplug event for disconnected port, ignoring\n"); | |
256 | } | |
257 | } else if (port->remote) { | |
258 | tb_port_info(port, | |
259 | "got plug event for connected port, ignoring\n"); | |
260 | } else { | |
261 | tb_port_info(port, "hotplug: scanning\n"); | |
262 | tb_scan_port(port); | |
263 | if (!port->remote) { | |
264 | tb_port_info(port, "hotplug: no switch found\n"); | |
265 | } else if (port->remote->sw->config.depth > 1) { | |
266 | tb_sw_warn(port->remote->sw, | |
267 | "hotplug: chaining not supported\n"); | |
3364f0c1 AN |
268 | } else { |
269 | tb_sw_info(port->remote->sw, | |
270 | "hotplug: activating pcie devices\n"); | |
271 | tb_activate_pcie_devices(tb); | |
053596d9 AN |
272 | } |
273 | } | |
d6cc51cd AN |
274 | out: |
275 | mutex_unlock(&tb->lock); | |
276 | kfree(ev); | |
277 | } | |
278 | ||
279 | /** | |
280 | * tb_schedule_hotplug_handler() - callback function for the control channel | |
281 | * | |
282 | * Delegates to tb_handle_hotplug. | |
283 | */ | |
284 | static void tb_schedule_hotplug_handler(void *data, u64 route, u8 port, | |
285 | bool unplug) | |
286 | { | |
287 | struct tb *tb = data; | |
288 | struct tb_hotplug_event *ev = kmalloc(sizeof(*ev), GFP_KERNEL); | |
289 | if (!ev) | |
290 | return; | |
291 | INIT_WORK(&ev->work, tb_handle_hotplug); | |
292 | ev->tb = tb; | |
293 | ev->route = route; | |
294 | ev->port = port; | |
295 | ev->unplug = unplug; | |
296 | queue_work(tb->wq, &ev->work); | |
297 | } | |
298 | ||
299 | /** | |
300 | * thunderbolt_shutdown_and_free() - shutdown everything | |
301 | * | |
302 | * Free all switches and the config channel. | |
303 | * | |
304 | * Used in the error path of thunderbolt_alloc_and_start. | |
305 | */ | |
306 | void thunderbolt_shutdown_and_free(struct tb *tb) | |
307 | { | |
3364f0c1 AN |
308 | struct tb_pci_tunnel *tunnel; |
309 | struct tb_pci_tunnel *n; | |
310 | ||
d6cc51cd AN |
311 | mutex_lock(&tb->lock); |
312 | ||
3364f0c1 AN |
313 | /* tunnels are only present after everything has been initialized */ |
314 | list_for_each_entry_safe(tunnel, n, &tb->tunnel_list, list) { | |
315 | tb_pci_deactivate(tunnel); | |
316 | tb_pci_free(tunnel); | |
317 | } | |
318 | ||
a25c8b2f AN |
319 | if (tb->root_switch) |
320 | tb_switch_free(tb->root_switch); | |
321 | tb->root_switch = NULL; | |
322 | ||
d6cc51cd AN |
323 | if (tb->ctl) { |
324 | tb_ctl_stop(tb->ctl); | |
325 | tb_ctl_free(tb->ctl); | |
326 | } | |
327 | tb->ctl = NULL; | |
328 | tb->hotplug_active = false; /* signal tb_handle_hotplug to quit */ | |
329 | ||
330 | /* allow tb_handle_hotplug to acquire the lock */ | |
331 | mutex_unlock(&tb->lock); | |
332 | if (tb->wq) { | |
333 | flush_workqueue(tb->wq); | |
334 | destroy_workqueue(tb->wq); | |
335 | tb->wq = NULL; | |
336 | } | |
337 | mutex_destroy(&tb->lock); | |
338 | kfree(tb); | |
339 | } | |
340 | ||
341 | /** | |
342 | * thunderbolt_alloc_and_start() - setup the thunderbolt bus | |
343 | * | |
344 | * Allocates a tb_cfg control channel, initializes the root switch, enables | |
345 | * plug events and activates pci devices. | |
346 | * | |
347 | * Return: Returns NULL on error. | |
348 | */ | |
349 | struct tb *thunderbolt_alloc_and_start(struct tb_nhi *nhi) | |
350 | { | |
351 | struct tb *tb; | |
352 | ||
7adf6097 AN |
353 | BUILD_BUG_ON(sizeof(struct tb_regs_switch_header) != 5 * 4); |
354 | BUILD_BUG_ON(sizeof(struct tb_regs_port_header) != 8 * 4); | |
355 | BUILD_BUG_ON(sizeof(struct tb_regs_hop) != 2 * 4); | |
356 | ||
d6cc51cd AN |
357 | tb = kzalloc(sizeof(*tb), GFP_KERNEL); |
358 | if (!tb) | |
359 | return NULL; | |
360 | ||
361 | tb->nhi = nhi; | |
362 | mutex_init(&tb->lock); | |
363 | mutex_lock(&tb->lock); | |
3364f0c1 | 364 | INIT_LIST_HEAD(&tb->tunnel_list); |
d6cc51cd AN |
365 | |
366 | tb->wq = alloc_ordered_workqueue("thunderbolt", 0); | |
367 | if (!tb->wq) | |
368 | goto err_locked; | |
369 | ||
370 | tb->ctl = tb_ctl_alloc(tb->nhi, tb_schedule_hotplug_handler, tb); | |
371 | if (!tb->ctl) | |
372 | goto err_locked; | |
373 | /* | |
374 | * tb_schedule_hotplug_handler may be called as soon as the config | |
375 | * channel is started. Thats why we have to hold the lock here. | |
376 | */ | |
377 | tb_ctl_start(tb->ctl); | |
378 | ||
a25c8b2f AN |
379 | tb->root_switch = tb_switch_alloc(tb, 0); |
380 | if (!tb->root_switch) | |
381 | goto err_locked; | |
382 | ||
9da672a4 AN |
383 | /* Full scan to discover devices added before the driver was loaded. */ |
384 | tb_scan_switch(tb->root_switch); | |
3364f0c1 | 385 | tb_activate_pcie_devices(tb); |
9da672a4 | 386 | |
d6cc51cd AN |
387 | /* Allow tb_handle_hotplug to progress events */ |
388 | tb->hotplug_active = true; | |
389 | mutex_unlock(&tb->lock); | |
390 | return tb; | |
391 | ||
392 | err_locked: | |
393 | mutex_unlock(&tb->lock); | |
394 | thunderbolt_shutdown_and_free(tb); | |
395 | return NULL; | |
396 | } | |
397 | ||
23dd5bb4 AN |
398 | void thunderbolt_suspend(struct tb *tb) |
399 | { | |
400 | tb_info(tb, "suspending...\n"); | |
401 | mutex_lock(&tb->lock); | |
402 | tb_switch_suspend(tb->root_switch); | |
403 | tb_ctl_stop(tb->ctl); | |
404 | tb->hotplug_active = false; /* signal tb_handle_hotplug to quit */ | |
405 | mutex_unlock(&tb->lock); | |
406 | tb_info(tb, "suspend finished\n"); | |
407 | } | |
408 | ||
409 | void thunderbolt_resume(struct tb *tb) | |
410 | { | |
411 | struct tb_pci_tunnel *tunnel, *n; | |
412 | tb_info(tb, "resuming...\n"); | |
413 | mutex_lock(&tb->lock); | |
414 | tb_ctl_start(tb->ctl); | |
415 | ||
416 | /* remove any pci devices the firmware might have setup */ | |
417 | tb_switch_reset(tb, 0); | |
418 | ||
419 | tb_switch_resume(tb->root_switch); | |
420 | tb_free_invalid_tunnels(tb); | |
421 | tb_free_unplugged_children(tb->root_switch); | |
422 | list_for_each_entry_safe(tunnel, n, &tb->tunnel_list, list) | |
423 | tb_pci_restart(tunnel); | |
424 | if (!list_empty(&tb->tunnel_list)) { | |
425 | /* | |
426 | * the pcie links need some time to get going. | |
427 | * 100ms works for me... | |
428 | */ | |
429 | tb_info(tb, "tunnels restarted, sleeping for 100ms\n"); | |
430 | msleep(100); | |
431 | } | |
432 | /* Allow tb_handle_hotplug to progress events */ | |
433 | tb->hotplug_active = true; | |
434 | mutex_unlock(&tb->lock); | |
435 | tb_info(tb, "resume finished\n"); | |
436 | } |