Commit | Line | Data |
---|---|---|
deb2d2ec | 1 | /* |
c0db9cbc TV |
2 | * vgaarb.c: Implements the VGA arbitration. For details refer to |
3 | * Documentation/vgaarbiter.txt | |
4 | * | |
deb2d2ec BH |
5 | * |
6 | * (C) Copyright 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org> | |
7 | * (C) Copyright 2007 Paulo R. Zanoni <przanoni@gmail.com> | |
8 | * (C) Copyright 2007, 2009 Tiago Vignatti <vignatti@freedesktop.org> | |
9 | * | |
c0db9cbc TV |
10 | * Permission is hereby granted, free of charge, to any person obtaining a |
11 | * copy of this software and associated documentation files (the "Software"), | |
12 | * to deal in the Software without restriction, including without limitation | |
13 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, | |
14 | * and/or sell copies of the Software, and to permit persons to whom the | |
15 | * Software is furnished to do so, subject to the following conditions: | |
16 | * | |
17 | * The above copyright notice and this permission notice (including the next | |
18 | * paragraph) shall be included in all copies or substantial portions of the | |
19 | * Software. | |
20 | * | |
21 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
22 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
23 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
24 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
25 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
26 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER | |
27 | * DEALINGS | |
28 | * IN THE SOFTWARE. | |
29 | * | |
deb2d2ec BH |
30 | */ |
31 | ||
32 | #include <linux/module.h> | |
33 | #include <linux/kernel.h> | |
34 | #include <linux/pci.h> | |
35 | #include <linux/errno.h> | |
36 | #include <linux/init.h> | |
37 | #include <linux/list.h> | |
38 | #include <linux/sched.h> | |
39 | #include <linux/wait.h> | |
40 | #include <linux/spinlock.h> | |
41 | #include <linux/poll.h> | |
42 | #include <linux/miscdevice.h> | |
5a0e3ad6 | 43 | #include <linux/slab.h> |
86fd887b | 44 | #include <linux/screen_info.h> |
deb2d2ec BH |
45 | |
46 | #include <linux/uaccess.h> | |
47 | ||
48 | #include <linux/vgaarb.h> | |
49 | ||
50 | static void vga_arbiter_notify_clients(void); | |
51 | /* | |
52 | * We keep a list of all vga devices in the system to speed | |
53 | * up the various operations of the arbiter | |
54 | */ | |
55 | struct vga_device { | |
56 | struct list_head list; | |
57 | struct pci_dev *pdev; | |
58 | unsigned int decodes; /* what does it decodes */ | |
59 | unsigned int owns; /* what does it owns */ | |
60 | unsigned int locks; /* what does it locks */ | |
61 | unsigned int io_lock_cnt; /* legacy IO lock count */ | |
62 | unsigned int mem_lock_cnt; /* legacy MEM lock count */ | |
63 | unsigned int io_norm_cnt; /* normal IO count */ | |
64 | unsigned int mem_norm_cnt; /* normal MEM count */ | |
3448a19d | 65 | bool bridge_has_one_vga; |
deb2d2ec BH |
66 | /* allow IRQ enable/disable hook */ |
67 | void *cookie; | |
68 | void (*irq_set_state)(void *cookie, bool enable); | |
69 | unsigned int (*set_vga_decode)(void *cookie, bool decode); | |
70 | }; | |
71 | ||
72 | static LIST_HEAD(vga_list); | |
73 | static int vga_count, vga_decode_count; | |
74 | static bool vga_arbiter_used; | |
75 | static DEFINE_SPINLOCK(vga_lock); | |
76 | static DECLARE_WAIT_QUEUE_HEAD(vga_wait_queue); | |
77 | ||
78 | ||
79 | static const char *vga_iostate_to_str(unsigned int iostate) | |
80 | { | |
81 | /* Ignore VGA_RSRC_IO and VGA_RSRC_MEM */ | |
82 | iostate &= VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
83 | switch (iostate) { | |
84 | case VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM: | |
85 | return "io+mem"; | |
86 | case VGA_RSRC_LEGACY_IO: | |
87 | return "io"; | |
88 | case VGA_RSRC_LEGACY_MEM: | |
89 | return "mem"; | |
90 | } | |
91 | return "none"; | |
92 | } | |
93 | ||
94 | static int vga_str_to_iostate(char *buf, int str_size, int *io_state) | |
95 | { | |
96 | /* we could in theory hand out locks on IO and mem | |
97 | * separately to userspace but it can cause deadlocks */ | |
98 | if (strncmp(buf, "none", 4) == 0) { | |
99 | *io_state = VGA_RSRC_NONE; | |
100 | return 1; | |
101 | } | |
102 | ||
103 | /* XXX We're not chekcing the str_size! */ | |
104 | if (strncmp(buf, "io+mem", 6) == 0) | |
105 | goto both; | |
106 | else if (strncmp(buf, "io", 2) == 0) | |
107 | goto both; | |
108 | else if (strncmp(buf, "mem", 3) == 0) | |
109 | goto both; | |
110 | return 0; | |
111 | both: | |
112 | *io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
113 | return 1; | |
114 | } | |
115 | ||
deb2d2ec BH |
116 | /* this is only used a cookie - it should not be dereferenced */ |
117 | static struct pci_dev *vga_default; | |
deb2d2ec BH |
118 | |
119 | static void vga_arb_device_card_gone(struct pci_dev *pdev); | |
120 | ||
121 | /* Find somebody in our list */ | |
122 | static struct vga_device *vgadev_find(struct pci_dev *pdev) | |
123 | { | |
124 | struct vga_device *vgadev; | |
125 | ||
126 | list_for_each_entry(vgadev, &vga_list, list) | |
127 | if (pdev == vgadev->pdev) | |
128 | return vgadev; | |
129 | return NULL; | |
130 | } | |
131 | ||
132 | /* Returns the default VGA device (vgacon's babe) */ | |
deb2d2ec BH |
133 | struct pci_dev *vga_default_device(void) |
134 | { | |
135 | return vga_default; | |
136 | } | |
1a39b310 | 137 | |
1b23170a MG |
138 | EXPORT_SYMBOL_GPL(vga_default_device); |
139 | ||
1a39b310 MG |
140 | void vga_set_default_device(struct pci_dev *pdev) |
141 | { | |
84544a1d YL |
142 | if (vga_default == pdev) |
143 | return; | |
144 | ||
145 | pci_dev_put(vga_default); | |
146 | vga_default = pci_dev_get(pdev); | |
1a39b310 | 147 | } |
deb2d2ec BH |
148 | |
149 | static inline void vga_irq_set_state(struct vga_device *vgadev, bool state) | |
150 | { | |
151 | if (vgadev->irq_set_state) | |
152 | vgadev->irq_set_state(vgadev->cookie, state); | |
153 | } | |
154 | ||
155 | ||
156 | /* If we don't ever use VGA arb we should avoid | |
157 | turning off anything anywhere due to old X servers getting | |
158 | confused about the boot device not being VGA */ | |
159 | static void vga_check_first_use(void) | |
160 | { | |
161 | /* we should inform all GPUs in the system that | |
25985edc | 162 | * VGA arb has occurred and to try and disable resources |
deb2d2ec BH |
163 | * if they can */ |
164 | if (!vga_arbiter_used) { | |
165 | vga_arbiter_used = true; | |
166 | vga_arbiter_notify_clients(); | |
167 | } | |
168 | } | |
169 | ||
170 | static struct vga_device *__vga_tryget(struct vga_device *vgadev, | |
171 | unsigned int rsrc) | |
172 | { | |
173 | unsigned int wants, legacy_wants, match; | |
174 | struct vga_device *conflict; | |
175 | unsigned int pci_bits; | |
3448a19d DA |
176 | u32 flags = 0; |
177 | ||
deb2d2ec BH |
178 | /* Account for "normal" resources to lock. If we decode the legacy, |
179 | * counterpart, we need to request it as well | |
180 | */ | |
181 | if ((rsrc & VGA_RSRC_NORMAL_IO) && | |
182 | (vgadev->decodes & VGA_RSRC_LEGACY_IO)) | |
183 | rsrc |= VGA_RSRC_LEGACY_IO; | |
184 | if ((rsrc & VGA_RSRC_NORMAL_MEM) && | |
185 | (vgadev->decodes & VGA_RSRC_LEGACY_MEM)) | |
186 | rsrc |= VGA_RSRC_LEGACY_MEM; | |
187 | ||
2d6e9b91 TV |
188 | pr_debug("%s: %d\n", __func__, rsrc); |
189 | pr_debug("%s: owns: %d\n", __func__, vgadev->owns); | |
deb2d2ec BH |
190 | |
191 | /* Check what resources we need to acquire */ | |
192 | wants = rsrc & ~vgadev->owns; | |
193 | ||
194 | /* We already own everything, just mark locked & bye bye */ | |
195 | if (wants == 0) | |
196 | goto lock_them; | |
197 | ||
198 | /* We don't need to request a legacy resource, we just enable | |
199 | * appropriate decoding and go | |
200 | */ | |
201 | legacy_wants = wants & VGA_RSRC_LEGACY_MASK; | |
202 | if (legacy_wants == 0) | |
203 | goto enable_them; | |
204 | ||
205 | /* Ok, we don't, let's find out how we need to kick off */ | |
206 | list_for_each_entry(conflict, &vga_list, list) { | |
207 | unsigned int lwants = legacy_wants; | |
208 | unsigned int change_bridge = 0; | |
209 | ||
210 | /* Don't conflict with myself */ | |
211 | if (vgadev == conflict) | |
212 | continue; | |
213 | ||
214 | /* Check if the architecture allows a conflict between those | |
215 | * 2 devices or if they are on separate domains | |
216 | */ | |
217 | if (!vga_conflicts(vgadev->pdev, conflict->pdev)) | |
218 | continue; | |
219 | ||
220 | /* We have a possible conflict. before we go further, we must | |
221 | * check if we sit on the same bus as the conflicting device. | |
222 | * if we don't, then we must tie both IO and MEM resources | |
223 | * together since there is only a single bit controlling | |
224 | * VGA forwarding on P2P bridges | |
225 | */ | |
226 | if (vgadev->pdev->bus != conflict->pdev->bus) { | |
227 | change_bridge = 1; | |
228 | lwants = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
229 | } | |
230 | ||
231 | /* Check if the guy has a lock on the resource. If he does, | |
232 | * return the conflicting entry | |
233 | */ | |
234 | if (conflict->locks & lwants) | |
235 | return conflict; | |
236 | ||
4e4e7dc5 AW |
237 | /* Ok, now check if it owns the resource we want. We can |
238 | * lock resources that are not decoded, therefore a device | |
239 | * can own resources it doesn't decode. | |
deb2d2ec | 240 | */ |
deb2d2ec BH |
241 | match = lwants & conflict->owns; |
242 | if (!match) | |
243 | continue; | |
244 | ||
245 | /* looks like he doesn't have a lock, we can steal | |
246 | * them from him | |
247 | */ | |
deb2d2ec | 248 | |
3448a19d | 249 | flags = 0; |
deb2d2ec | 250 | pci_bits = 0; |
deb2d2ec | 251 | |
4e4e7dc5 AW |
252 | /* If we can't control legacy resources via the bridge, we |
253 | * also need to disable normal decoding. | |
254 | */ | |
3448a19d | 255 | if (!conflict->bridge_has_one_vga) { |
4e4e7dc5 | 256 | if ((match & conflict->decodes) & VGA_RSRC_LEGACY_MEM) |
3448a19d | 257 | pci_bits |= PCI_COMMAND_MEMORY; |
4e4e7dc5 | 258 | if ((match & conflict->decodes) & VGA_RSRC_LEGACY_IO) |
3448a19d | 259 | pci_bits |= PCI_COMMAND_IO; |
4e4e7dc5 AW |
260 | |
261 | if (pci_bits) { | |
262 | vga_irq_set_state(conflict, false); | |
263 | flags |= PCI_VGA_STATE_CHANGE_DECODES; | |
264 | } | |
3448a19d DA |
265 | } |
266 | ||
267 | if (change_bridge) | |
268 | flags |= PCI_VGA_STATE_CHANGE_BRIDGE; | |
269 | ||
270 | pci_set_vga_state(conflict->pdev, false, pci_bits, flags); | |
f22d776f | 271 | conflict->owns &= ~match; |
4e4e7dc5 AW |
272 | |
273 | /* If we disabled normal decoding, reflect it in owns */ | |
274 | if (pci_bits & PCI_COMMAND_MEMORY) | |
deb2d2ec | 275 | conflict->owns &= ~VGA_RSRC_NORMAL_MEM; |
4e4e7dc5 | 276 | if (pci_bits & PCI_COMMAND_IO) |
deb2d2ec BH |
277 | conflict->owns &= ~VGA_RSRC_NORMAL_IO; |
278 | } | |
279 | ||
280 | enable_them: | |
281 | /* ok dude, we got it, everybody conflicting has been disabled, let's | |
4e4e7dc5 AW |
282 | * enable us. Mark any bits in "owns" regardless of whether we |
283 | * decoded them. We can lock resources we don't decode, therefore | |
284 | * we must track them via "owns". | |
deb2d2ec | 285 | */ |
3448a19d | 286 | flags = 0; |
deb2d2ec | 287 | pci_bits = 0; |
deb2d2ec | 288 | |
3448a19d DA |
289 | if (!vgadev->bridge_has_one_vga) { |
290 | flags |= PCI_VGA_STATE_CHANGE_DECODES; | |
291 | if (wants & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) | |
292 | pci_bits |= PCI_COMMAND_MEMORY; | |
293 | if (wants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) | |
294 | pci_bits |= PCI_COMMAND_IO; | |
295 | } | |
4e4e7dc5 | 296 | if (wants & VGA_RSRC_LEGACY_MASK) |
3448a19d DA |
297 | flags |= PCI_VGA_STATE_CHANGE_BRIDGE; |
298 | ||
299 | pci_set_vga_state(vgadev->pdev, true, pci_bits, flags); | |
300 | ||
301 | if (!vgadev->bridge_has_one_vga) { | |
302 | vga_irq_set_state(vgadev, true); | |
303 | } | |
4e4e7dc5 | 304 | vgadev->owns |= wants; |
deb2d2ec BH |
305 | lock_them: |
306 | vgadev->locks |= (rsrc & VGA_RSRC_LEGACY_MASK); | |
307 | if (rsrc & VGA_RSRC_LEGACY_IO) | |
308 | vgadev->io_lock_cnt++; | |
309 | if (rsrc & VGA_RSRC_LEGACY_MEM) | |
310 | vgadev->mem_lock_cnt++; | |
311 | if (rsrc & VGA_RSRC_NORMAL_IO) | |
312 | vgadev->io_norm_cnt++; | |
313 | if (rsrc & VGA_RSRC_NORMAL_MEM) | |
314 | vgadev->mem_norm_cnt++; | |
315 | ||
316 | return NULL; | |
317 | } | |
318 | ||
319 | static void __vga_put(struct vga_device *vgadev, unsigned int rsrc) | |
320 | { | |
321 | unsigned int old_locks = vgadev->locks; | |
322 | ||
2d6e9b91 | 323 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
324 | |
325 | /* Update our counters, and account for equivalent legacy resources | |
326 | * if we decode them | |
327 | */ | |
328 | if ((rsrc & VGA_RSRC_NORMAL_IO) && vgadev->io_norm_cnt > 0) { | |
329 | vgadev->io_norm_cnt--; | |
330 | if (vgadev->decodes & VGA_RSRC_LEGACY_IO) | |
331 | rsrc |= VGA_RSRC_LEGACY_IO; | |
332 | } | |
333 | if ((rsrc & VGA_RSRC_NORMAL_MEM) && vgadev->mem_norm_cnt > 0) { | |
334 | vgadev->mem_norm_cnt--; | |
335 | if (vgadev->decodes & VGA_RSRC_LEGACY_MEM) | |
336 | rsrc |= VGA_RSRC_LEGACY_MEM; | |
337 | } | |
338 | if ((rsrc & VGA_RSRC_LEGACY_IO) && vgadev->io_lock_cnt > 0) | |
339 | vgadev->io_lock_cnt--; | |
340 | if ((rsrc & VGA_RSRC_LEGACY_MEM) && vgadev->mem_lock_cnt > 0) | |
341 | vgadev->mem_lock_cnt--; | |
342 | ||
343 | /* Just clear lock bits, we do lazy operations so we don't really | |
344 | * have to bother about anything else at this point | |
345 | */ | |
346 | if (vgadev->io_lock_cnt == 0) | |
347 | vgadev->locks &= ~VGA_RSRC_LEGACY_IO; | |
348 | if (vgadev->mem_lock_cnt == 0) | |
349 | vgadev->locks &= ~VGA_RSRC_LEGACY_MEM; | |
350 | ||
351 | /* Kick the wait queue in case somebody was waiting if we actually | |
352 | * released something | |
353 | */ | |
354 | if (old_locks != vgadev->locks) | |
355 | wake_up_all(&vga_wait_queue); | |
356 | } | |
357 | ||
358 | int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible) | |
359 | { | |
360 | struct vga_device *vgadev, *conflict; | |
361 | unsigned long flags; | |
362 | wait_queue_t wait; | |
363 | int rc = 0; | |
364 | ||
365 | vga_check_first_use(); | |
366 | /* The one who calls us should check for this, but lets be sure... */ | |
367 | if (pdev == NULL) | |
368 | pdev = vga_default_device(); | |
369 | if (pdev == NULL) | |
370 | return 0; | |
371 | ||
372 | for (;;) { | |
373 | spin_lock_irqsave(&vga_lock, flags); | |
374 | vgadev = vgadev_find(pdev); | |
375 | if (vgadev == NULL) { | |
376 | spin_unlock_irqrestore(&vga_lock, flags); | |
377 | rc = -ENODEV; | |
378 | break; | |
379 | } | |
380 | conflict = __vga_tryget(vgadev, rsrc); | |
381 | spin_unlock_irqrestore(&vga_lock, flags); | |
382 | if (conflict == NULL) | |
383 | break; | |
384 | ||
385 | ||
386 | /* We have a conflict, we wait until somebody kicks the | |
387 | * work queue. Currently we have one work queue that we | |
388 | * kick each time some resources are released, but it would | |
389 | * be fairly easy to have a per device one so that we only | |
390 | * need to attach to the conflicting device | |
391 | */ | |
392 | init_waitqueue_entry(&wait, current); | |
393 | add_wait_queue(&vga_wait_queue, &wait); | |
394 | set_current_state(interruptible ? | |
395 | TASK_INTERRUPTIBLE : | |
396 | TASK_UNINTERRUPTIBLE); | |
397 | if (signal_pending(current)) { | |
398 | rc = -EINTR; | |
399 | break; | |
400 | } | |
401 | schedule(); | |
402 | remove_wait_queue(&vga_wait_queue, &wait); | |
deb2d2ec BH |
403 | } |
404 | return rc; | |
405 | } | |
406 | EXPORT_SYMBOL(vga_get); | |
407 | ||
408 | int vga_tryget(struct pci_dev *pdev, unsigned int rsrc) | |
409 | { | |
410 | struct vga_device *vgadev; | |
411 | unsigned long flags; | |
412 | int rc = 0; | |
413 | ||
414 | vga_check_first_use(); | |
415 | ||
416 | /* The one who calls us should check for this, but lets be sure... */ | |
417 | if (pdev == NULL) | |
418 | pdev = vga_default_device(); | |
419 | if (pdev == NULL) | |
420 | return 0; | |
421 | spin_lock_irqsave(&vga_lock, flags); | |
422 | vgadev = vgadev_find(pdev); | |
423 | if (vgadev == NULL) { | |
424 | rc = -ENODEV; | |
425 | goto bail; | |
426 | } | |
427 | if (__vga_tryget(vgadev, rsrc)) | |
428 | rc = -EBUSY; | |
429 | bail: | |
430 | spin_unlock_irqrestore(&vga_lock, flags); | |
431 | return rc; | |
432 | } | |
433 | EXPORT_SYMBOL(vga_tryget); | |
434 | ||
435 | void vga_put(struct pci_dev *pdev, unsigned int rsrc) | |
436 | { | |
437 | struct vga_device *vgadev; | |
438 | unsigned long flags; | |
439 | ||
440 | /* The one who calls us should check for this, but lets be sure... */ | |
441 | if (pdev == NULL) | |
442 | pdev = vga_default_device(); | |
443 | if (pdev == NULL) | |
444 | return; | |
445 | spin_lock_irqsave(&vga_lock, flags); | |
446 | vgadev = vgadev_find(pdev); | |
447 | if (vgadev == NULL) | |
448 | goto bail; | |
449 | __vga_put(vgadev, rsrc); | |
450 | bail: | |
451 | spin_unlock_irqrestore(&vga_lock, flags); | |
452 | } | |
453 | EXPORT_SYMBOL(vga_put); | |
454 | ||
3448a19d DA |
455 | /* Rules for using a bridge to control a VGA descendant decoding: |
456 | if a bridge has only one VGA descendant then it can be used | |
457 | to control the VGA routing for that device. | |
458 | It should always use the bridge closest to the device to control it. | |
459 | If a bridge has a direct VGA descendant, but also have a sub-bridge | |
460 | VGA descendant then we cannot use that bridge to control the direct VGA descendant. | |
461 | So for every device we register, we need to iterate all its parent bridges | |
462 | so we can invalidate any devices using them properly. | |
463 | */ | |
464 | static void vga_arbiter_check_bridge_sharing(struct vga_device *vgadev) | |
465 | { | |
466 | struct vga_device *same_bridge_vgadev; | |
467 | struct pci_bus *new_bus, *bus; | |
468 | struct pci_dev *new_bridge, *bridge; | |
469 | ||
470 | vgadev->bridge_has_one_vga = true; | |
471 | ||
472 | if (list_empty(&vga_list)) | |
473 | return; | |
474 | ||
475 | /* okay iterate the new devices bridge hierarachy */ | |
476 | new_bus = vgadev->pdev->bus; | |
477 | while (new_bus) { | |
478 | new_bridge = new_bus->self; | |
479 | ||
f6252114 DA |
480 | /* go through list of devices already registered */ |
481 | list_for_each_entry(same_bridge_vgadev, &vga_list, list) { | |
482 | bus = same_bridge_vgadev->pdev->bus; | |
483 | bridge = bus->self; | |
484 | ||
485 | /* see if the share a bridge with this device */ | |
486 | if (new_bridge == bridge) { | |
487 | /* if their direct parent bridge is the same | |
488 | as any bridge of this device then it can't be used | |
489 | for that device */ | |
490 | same_bridge_vgadev->bridge_has_one_vga = false; | |
491 | } | |
3448a19d | 492 | |
f6252114 DA |
493 | /* now iterate the previous devices bridge hierarchy */ |
494 | /* if the new devices parent bridge is in the other devices | |
495 | hierarchy then we can't use it to control this device */ | |
496 | while (bus) { | |
497 | bridge = bus->self; | |
498 | if (bridge) { | |
499 | if (bridge == vgadev->pdev->bus->self) | |
500 | vgadev->bridge_has_one_vga = false; | |
3448a19d | 501 | } |
f6252114 | 502 | bus = bus->parent; |
3448a19d DA |
503 | } |
504 | } | |
505 | new_bus = new_bus->parent; | |
506 | } | |
507 | } | |
508 | ||
deb2d2ec BH |
509 | /* |
510 | * Currently, we assume that the "initial" setup of the system is | |
511 | * not sane, that is we come up with conflicting devices and let | |
512 | * the arbiter's client decides if devices decodes or not legacy | |
513 | * things. | |
514 | */ | |
515 | static bool vga_arbiter_add_pci_device(struct pci_dev *pdev) | |
516 | { | |
517 | struct vga_device *vgadev; | |
518 | unsigned long flags; | |
519 | struct pci_bus *bus; | |
520 | struct pci_dev *bridge; | |
521 | u16 cmd; | |
522 | ||
523 | /* Only deal with VGA class devices */ | |
524 | if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA) | |
525 | return false; | |
526 | ||
527 | /* Allocate structure */ | |
528 | vgadev = kmalloc(sizeof(struct vga_device), GFP_KERNEL); | |
529 | if (vgadev == NULL) { | |
530 | pr_err("vgaarb: failed to allocate pci device\n"); | |
531 | /* What to do on allocation failure ? For now, let's | |
532 | * just do nothing, I'm not sure there is anything saner | |
533 | * to be done | |
534 | */ | |
535 | return false; | |
536 | } | |
537 | ||
538 | memset(vgadev, 0, sizeof(*vgadev)); | |
539 | ||
540 | /* Take lock & check for duplicates */ | |
541 | spin_lock_irqsave(&vga_lock, flags); | |
542 | if (vgadev_find(pdev) != NULL) { | |
543 | BUG_ON(1); | |
544 | goto fail; | |
545 | } | |
546 | vgadev->pdev = pdev; | |
547 | ||
548 | /* By default, assume we decode everything */ | |
549 | vgadev->decodes = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM | | |
550 | VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM; | |
551 | ||
552 | /* by default mark it as decoding */ | |
553 | vga_decode_count++; | |
554 | /* Mark that we "own" resources based on our enables, we will | |
555 | * clear that below if the bridge isn't forwarding | |
556 | */ | |
557 | pci_read_config_word(pdev, PCI_COMMAND, &cmd); | |
558 | if (cmd & PCI_COMMAND_IO) | |
559 | vgadev->owns |= VGA_RSRC_LEGACY_IO; | |
560 | if (cmd & PCI_COMMAND_MEMORY) | |
561 | vgadev->owns |= VGA_RSRC_LEGACY_MEM; | |
562 | ||
563 | /* Check if VGA cycles can get down to us */ | |
564 | bus = pdev->bus; | |
565 | while (bus) { | |
566 | bridge = bus->self; | |
567 | if (bridge) { | |
568 | u16 l; | |
569 | pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, | |
570 | &l); | |
571 | if (!(l & PCI_BRIDGE_CTL_VGA)) { | |
572 | vgadev->owns = 0; | |
573 | break; | |
574 | } | |
575 | } | |
576 | bus = bus->parent; | |
577 | } | |
578 | ||
579 | /* Deal with VGA default device. Use first enabled one | |
580 | * by default if arch doesn't have it's own hook | |
581 | */ | |
deb2d2ec | 582 | if (vga_default == NULL && |
86fd887b BP |
583 | ((vgadev->owns & VGA_RSRC_LEGACY_MASK) == VGA_RSRC_LEGACY_MASK)) { |
584 | pr_info("vgaarb: setting as boot device: PCI:%s\n", | |
585 | pci_name(pdev)); | |
84544a1d | 586 | vga_set_default_device(pdev); |
86fd887b | 587 | } |
deb2d2ec | 588 | |
3448a19d DA |
589 | vga_arbiter_check_bridge_sharing(vgadev); |
590 | ||
deb2d2ec BH |
591 | /* Add to the list */ |
592 | list_add(&vgadev->list, &vga_list); | |
593 | vga_count++; | |
594 | pr_info("vgaarb: device added: PCI:%s,decodes=%s,owns=%s,locks=%s\n", | |
595 | pci_name(pdev), | |
596 | vga_iostate_to_str(vgadev->decodes), | |
597 | vga_iostate_to_str(vgadev->owns), | |
598 | vga_iostate_to_str(vgadev->locks)); | |
599 | ||
600 | spin_unlock_irqrestore(&vga_lock, flags); | |
601 | return true; | |
602 | fail: | |
603 | spin_unlock_irqrestore(&vga_lock, flags); | |
604 | kfree(vgadev); | |
605 | return false; | |
606 | } | |
607 | ||
608 | static bool vga_arbiter_del_pci_device(struct pci_dev *pdev) | |
609 | { | |
610 | struct vga_device *vgadev; | |
611 | unsigned long flags; | |
612 | bool ret = true; | |
613 | ||
614 | spin_lock_irqsave(&vga_lock, flags); | |
615 | vgadev = vgadev_find(pdev); | |
616 | if (vgadev == NULL) { | |
617 | ret = false; | |
618 | goto bail; | |
619 | } | |
620 | ||
84544a1d YL |
621 | if (vga_default == pdev) |
622 | vga_set_default_device(NULL); | |
deb2d2ec BH |
623 | |
624 | if (vgadev->decodes & (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)) | |
625 | vga_decode_count--; | |
626 | ||
627 | /* Remove entry from list */ | |
628 | list_del(&vgadev->list); | |
629 | vga_count--; | |
630 | /* Notify userland driver that the device is gone so it discards | |
631 | * it's copies of the pci_dev pointer | |
632 | */ | |
633 | vga_arb_device_card_gone(pdev); | |
634 | ||
635 | /* Wake up all possible waiters */ | |
636 | wake_up_all(&vga_wait_queue); | |
637 | bail: | |
638 | spin_unlock_irqrestore(&vga_lock, flags); | |
639 | kfree(vgadev); | |
640 | return ret; | |
641 | } | |
642 | ||
643 | /* this is called with the lock */ | |
644 | static inline void vga_update_device_decodes(struct vga_device *vgadev, | |
645 | int new_decodes) | |
646 | { | |
5c0f6ee7 | 647 | int old_decodes, decodes_removed, decodes_unlocked; |
deb2d2ec BH |
648 | |
649 | old_decodes = vgadev->decodes; | |
5c0f6ee7 AW |
650 | decodes_removed = ~new_decodes & old_decodes; |
651 | decodes_unlocked = vgadev->locks & decodes_removed; | |
deb2d2ec BH |
652 | vgadev->decodes = new_decodes; |
653 | ||
654 | pr_info("vgaarb: device changed decodes: PCI:%s,olddecodes=%s,decodes=%s:owns=%s\n", | |
655 | pci_name(vgadev->pdev), | |
656 | vga_iostate_to_str(old_decodes), | |
657 | vga_iostate_to_str(vgadev->decodes), | |
658 | vga_iostate_to_str(vgadev->owns)); | |
659 | ||
5c0f6ee7 AW |
660 | /* if we removed locked decodes, lock count goes to zero, and release */ |
661 | if (decodes_unlocked) { | |
662 | if (decodes_unlocked & VGA_RSRC_LEGACY_IO) | |
663 | vgadev->io_lock_cnt = 0; | |
664 | if (decodes_unlocked & VGA_RSRC_LEGACY_MEM) | |
665 | vgadev->mem_lock_cnt = 0; | |
666 | __vga_put(vgadev, decodes_unlocked); | |
deb2d2ec BH |
667 | } |
668 | ||
669 | /* change decodes counter */ | |
5c0f6ee7 AW |
670 | if (old_decodes & VGA_RSRC_LEGACY_MASK && |
671 | !(new_decodes & VGA_RSRC_LEGACY_MASK)) | |
672 | vga_decode_count--; | |
673 | if (!(old_decodes & VGA_RSRC_LEGACY_MASK) && | |
674 | new_decodes & VGA_RSRC_LEGACY_MASK) | |
675 | vga_decode_count++; | |
2d6e9b91 | 676 | pr_debug("vgaarb: decoding count now is: %d\n", vga_decode_count); |
deb2d2ec BH |
677 | } |
678 | ||
201ba4c4 | 679 | static void __vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes, bool userspace) |
deb2d2ec BH |
680 | { |
681 | struct vga_device *vgadev; | |
682 | unsigned long flags; | |
683 | ||
684 | decodes &= VGA_RSRC_LEGACY_MASK; | |
685 | ||
686 | spin_lock_irqsave(&vga_lock, flags); | |
687 | vgadev = vgadev_find(pdev); | |
688 | if (vgadev == NULL) | |
689 | goto bail; | |
690 | ||
691 | /* don't let userspace futz with kernel driver decodes */ | |
692 | if (userspace && vgadev->set_vga_decode) | |
693 | goto bail; | |
694 | ||
695 | /* update the device decodes + counter */ | |
696 | vga_update_device_decodes(vgadev, decodes); | |
697 | ||
698 | /* XXX if somebody is going from "doesn't decode" to "decodes" state | |
699 | * here, additional care must be taken as we may have pending owner | |
700 | * ship of non-legacy region ... | |
701 | */ | |
702 | bail: | |
703 | spin_unlock_irqrestore(&vga_lock, flags); | |
704 | } | |
705 | ||
706 | void vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes) | |
707 | { | |
708 | __vga_set_legacy_decoding(pdev, decodes, false); | |
709 | } | |
710 | EXPORT_SYMBOL(vga_set_legacy_decoding); | |
711 | ||
deb2d2ec BH |
712 | /* call with NULL to unregister */ |
713 | int vga_client_register(struct pci_dev *pdev, void *cookie, | |
714 | void (*irq_set_state)(void *cookie, bool state), | |
715 | unsigned int (*set_vga_decode)(void *cookie, bool decode)) | |
716 | { | |
934f992c | 717 | int ret = -ENODEV; |
deb2d2ec BH |
718 | struct vga_device *vgadev; |
719 | unsigned long flags; | |
720 | ||
721 | spin_lock_irqsave(&vga_lock, flags); | |
722 | vgadev = vgadev_find(pdev); | |
723 | if (!vgadev) | |
724 | goto bail; | |
725 | ||
726 | vgadev->irq_set_state = irq_set_state; | |
727 | vgadev->set_vga_decode = set_vga_decode; | |
728 | vgadev->cookie = cookie; | |
729 | ret = 0; | |
730 | ||
731 | bail: | |
732 | spin_unlock_irqrestore(&vga_lock, flags); | |
733 | return ret; | |
734 | ||
735 | } | |
736 | EXPORT_SYMBOL(vga_client_register); | |
737 | ||
738 | /* | |
739 | * Char driver implementation | |
740 | * | |
741 | * Semantics is: | |
742 | * | |
743 | * open : open user instance of the arbitrer. by default, it's | |
744 | * attached to the default VGA device of the system. | |
745 | * | |
746 | * close : close user instance, release locks | |
747 | * | |
748 | * read : return a string indicating the status of the target. | |
749 | * an IO state string is of the form {io,mem,io+mem,none}, | |
750 | * mc and ic are respectively mem and io lock counts (for | |
751 | * debugging/diagnostic only). "decodes" indicate what the | |
752 | * card currently decodes, "owns" indicates what is currently | |
753 | * enabled on it, and "locks" indicates what is locked by this | |
754 | * card. If the card is unplugged, we get "invalid" then for | |
755 | * card_ID and an -ENODEV error is returned for any command | |
756 | * until a new card is targeted | |
757 | * | |
758 | * "<card_ID>,decodes=<io_state>,owns=<io_state>,locks=<io_state> (ic,mc)" | |
759 | * | |
760 | * write : write a command to the arbiter. List of commands is: | |
761 | * | |
762 | * target <card_ID> : switch target to card <card_ID> (see below) | |
763 | * lock <io_state> : acquires locks on target ("none" is invalid io_state) | |
764 | * trylock <io_state> : non-blocking acquire locks on target | |
765 | * unlock <io_state> : release locks on target | |
766 | * unlock all : release all locks on target held by this user | |
767 | * decodes <io_state> : set the legacy decoding attributes for the card | |
768 | * | |
769 | * poll : event if something change on any card (not just the target) | |
770 | * | |
771 | * card_ID is of the form "PCI:domain:bus:dev.fn". It can be set to "default" | |
772 | * to go back to the system default card (TODO: not implemented yet). | |
773 | * Currently, only PCI is supported as a prefix, but the userland API may | |
774 | * support other bus types in the future, even if the current kernel | |
775 | * implementation doesn't. | |
776 | * | |
777 | * Note about locks: | |
778 | * | |
779 | * The driver keeps track of which user has what locks on which card. It | |
780 | * supports stacking, like the kernel one. This complexifies the implementation | |
781 | * a bit, but makes the arbiter more tolerant to userspace problems and able | |
782 | * to properly cleanup in all cases when a process dies. | |
783 | * Currently, a max of 16 cards simultaneously can have locks issued from | |
784 | * userspace for a given user (file descriptor instance) of the arbiter. | |
785 | * | |
786 | * If the device is hot-unplugged, there is a hook inside the module to notify | |
787 | * they being added/removed in the system and automatically added/removed in | |
788 | * the arbiter. | |
789 | */ | |
790 | ||
36028f33 | 791 | #define MAX_USER_CARDS CONFIG_VGA_ARB_MAX_GPUS |
deb2d2ec BH |
792 | #define PCI_INVALID_CARD ((struct pci_dev *)-1UL) |
793 | ||
794 | /* | |
795 | * Each user has an array of these, tracking which cards have locks | |
796 | */ | |
797 | struct vga_arb_user_card { | |
798 | struct pci_dev *pdev; | |
799 | unsigned int mem_cnt; | |
800 | unsigned int io_cnt; | |
801 | }; | |
802 | ||
803 | struct vga_arb_private { | |
804 | struct list_head list; | |
805 | struct pci_dev *target; | |
806 | struct vga_arb_user_card cards[MAX_USER_CARDS]; | |
807 | spinlock_t lock; | |
808 | }; | |
809 | ||
810 | static LIST_HEAD(vga_user_list); | |
811 | static DEFINE_SPINLOCK(vga_user_lock); | |
812 | ||
813 | ||
814 | /* | |
815 | * This function gets a string in the format: "PCI:domain:bus:dev.fn" and | |
816 | * returns the respective values. If the string is not in this format, | |
817 | * it returns 0. | |
818 | */ | |
819 | static int vga_pci_str_to_vars(char *buf, int count, unsigned int *domain, | |
820 | unsigned int *bus, unsigned int *devfn) | |
821 | { | |
822 | int n; | |
823 | unsigned int slot, func; | |
824 | ||
825 | ||
826 | n = sscanf(buf, "PCI:%x:%x:%x.%x", domain, bus, &slot, &func); | |
827 | if (n != 4) | |
828 | return 0; | |
829 | ||
830 | *devfn = PCI_DEVFN(slot, func); | |
831 | ||
832 | return 1; | |
833 | } | |
834 | ||
835 | static ssize_t vga_arb_read(struct file *file, char __user * buf, | |
836 | size_t count, loff_t *ppos) | |
837 | { | |
838 | struct vga_arb_private *priv = file->private_data; | |
839 | struct vga_device *vgadev; | |
840 | struct pci_dev *pdev; | |
841 | unsigned long flags; | |
842 | size_t len; | |
843 | int rc; | |
844 | char *lbuf; | |
845 | ||
846 | lbuf = kmalloc(1024, GFP_KERNEL); | |
847 | if (lbuf == NULL) | |
848 | return -ENOMEM; | |
849 | ||
850 | /* Shields against vga_arb_device_card_gone (pci_dev going | |
851 | * away), and allows access to vga list | |
852 | */ | |
853 | spin_lock_irqsave(&vga_lock, flags); | |
854 | ||
25985edc | 855 | /* If we are targeting the default, use it */ |
deb2d2ec BH |
856 | pdev = priv->target; |
857 | if (pdev == NULL || pdev == PCI_INVALID_CARD) { | |
858 | spin_unlock_irqrestore(&vga_lock, flags); | |
859 | len = sprintf(lbuf, "invalid"); | |
860 | goto done; | |
861 | } | |
862 | ||
863 | /* Find card vgadev structure */ | |
864 | vgadev = vgadev_find(pdev); | |
865 | if (vgadev == NULL) { | |
866 | /* Wow, it's not in the list, that shouldn't happen, | |
867 | * let's fix us up and return invalid card | |
868 | */ | |
869 | if (pdev == priv->target) | |
870 | vga_arb_device_card_gone(pdev); | |
871 | spin_unlock_irqrestore(&vga_lock, flags); | |
872 | len = sprintf(lbuf, "invalid"); | |
873 | goto done; | |
874 | } | |
875 | ||
876 | /* Fill the buffer with infos */ | |
877 | len = snprintf(lbuf, 1024, | |
878 | "count:%d,PCI:%s,decodes=%s,owns=%s,locks=%s(%d:%d)\n", | |
879 | vga_decode_count, pci_name(pdev), | |
880 | vga_iostate_to_str(vgadev->decodes), | |
881 | vga_iostate_to_str(vgadev->owns), | |
882 | vga_iostate_to_str(vgadev->locks), | |
883 | vgadev->io_lock_cnt, vgadev->mem_lock_cnt); | |
884 | ||
885 | spin_unlock_irqrestore(&vga_lock, flags); | |
886 | done: | |
887 | ||
888 | /* Copy that to user */ | |
889 | if (len > count) | |
890 | len = count; | |
891 | rc = copy_to_user(buf, lbuf, len); | |
892 | kfree(lbuf); | |
893 | if (rc) | |
894 | return -EFAULT; | |
895 | return len; | |
896 | } | |
897 | ||
898 | /* | |
899 | * TODO: To avoid parsing inside kernel and to improve the speed we may | |
900 | * consider use ioctl here | |
901 | */ | |
902 | static ssize_t vga_arb_write(struct file *file, const char __user * buf, | |
903 | size_t count, loff_t *ppos) | |
904 | { | |
905 | struct vga_arb_private *priv = file->private_data; | |
906 | struct vga_arb_user_card *uc = NULL; | |
907 | struct pci_dev *pdev; | |
908 | ||
909 | unsigned int io_state; | |
910 | ||
911 | char *kbuf, *curr_pos; | |
912 | size_t remaining = count; | |
913 | ||
914 | int ret_val; | |
915 | int i; | |
916 | ||
917 | ||
918 | kbuf = kmalloc(count + 1, GFP_KERNEL); | |
919 | if (!kbuf) | |
920 | return -ENOMEM; | |
921 | ||
922 | if (copy_from_user(kbuf, buf, count)) { | |
923 | kfree(kbuf); | |
924 | return -EFAULT; | |
925 | } | |
926 | curr_pos = kbuf; | |
927 | kbuf[count] = '\0'; /* Just to make sure... */ | |
928 | ||
929 | if (strncmp(curr_pos, "lock ", 5) == 0) { | |
930 | curr_pos += 5; | |
931 | remaining -= 5; | |
932 | ||
2d6e9b91 | 933 | pr_debug("client 0x%p called 'lock'\n", priv); |
deb2d2ec BH |
934 | |
935 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
936 | ret_val = -EPROTO; | |
937 | goto done; | |
938 | } | |
939 | if (io_state == VGA_RSRC_NONE) { | |
940 | ret_val = -EPROTO; | |
941 | goto done; | |
942 | } | |
943 | ||
944 | pdev = priv->target; | |
945 | if (priv->target == NULL) { | |
946 | ret_val = -ENODEV; | |
947 | goto done; | |
948 | } | |
949 | ||
950 | vga_get_uninterruptible(pdev, io_state); | |
951 | ||
952 | /* Update the client's locks lists... */ | |
953 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
954 | if (priv->cards[i].pdev == pdev) { | |
955 | if (io_state & VGA_RSRC_LEGACY_IO) | |
956 | priv->cards[i].io_cnt++; | |
957 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
958 | priv->cards[i].mem_cnt++; | |
959 | break; | |
960 | } | |
961 | } | |
962 | ||
963 | ret_val = count; | |
964 | goto done; | |
965 | } else if (strncmp(curr_pos, "unlock ", 7) == 0) { | |
966 | curr_pos += 7; | |
967 | remaining -= 7; | |
968 | ||
2d6e9b91 | 969 | pr_debug("client 0x%p called 'unlock'\n", priv); |
deb2d2ec BH |
970 | |
971 | if (strncmp(curr_pos, "all", 3) == 0) | |
972 | io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
973 | else { | |
974 | if (!vga_str_to_iostate | |
975 | (curr_pos, remaining, &io_state)) { | |
976 | ret_val = -EPROTO; | |
977 | goto done; | |
978 | } | |
979 | /* TODO: Add this? | |
980 | if (io_state == VGA_RSRC_NONE) { | |
981 | ret_val = -EPROTO; | |
982 | goto done; | |
983 | } | |
984 | */ | |
985 | } | |
986 | ||
987 | pdev = priv->target; | |
988 | if (priv->target == NULL) { | |
989 | ret_val = -ENODEV; | |
990 | goto done; | |
991 | } | |
992 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
993 | if (priv->cards[i].pdev == pdev) | |
994 | uc = &priv->cards[i]; | |
995 | } | |
996 | ||
c916874d JL |
997 | if (!uc) { |
998 | ret_val = -EINVAL; | |
999 | goto done; | |
1000 | } | |
deb2d2ec | 1001 | |
c916874d JL |
1002 | if (io_state & VGA_RSRC_LEGACY_IO && uc->io_cnt == 0) { |
1003 | ret_val = -EINVAL; | |
1004 | goto done; | |
1005 | } | |
deb2d2ec | 1006 | |
c916874d JL |
1007 | if (io_state & VGA_RSRC_LEGACY_MEM && uc->mem_cnt == 0) { |
1008 | ret_val = -EINVAL; | |
1009 | goto done; | |
1010 | } | |
deb2d2ec BH |
1011 | |
1012 | vga_put(pdev, io_state); | |
1013 | ||
1014 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1015 | uc->io_cnt--; | |
1016 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1017 | uc->mem_cnt--; | |
1018 | ||
1019 | ret_val = count; | |
1020 | goto done; | |
1021 | } else if (strncmp(curr_pos, "trylock ", 8) == 0) { | |
1022 | curr_pos += 8; | |
1023 | remaining -= 8; | |
1024 | ||
2d6e9b91 | 1025 | pr_debug("client 0x%p called 'trylock'\n", priv); |
deb2d2ec BH |
1026 | |
1027 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1028 | ret_val = -EPROTO; | |
1029 | goto done; | |
1030 | } | |
1031 | /* TODO: Add this? | |
1032 | if (io_state == VGA_RSRC_NONE) { | |
1033 | ret_val = -EPROTO; | |
1034 | goto done; | |
1035 | } | |
1036 | */ | |
1037 | ||
1038 | pdev = priv->target; | |
1039 | if (priv->target == NULL) { | |
1040 | ret_val = -ENODEV; | |
1041 | goto done; | |
1042 | } | |
1043 | ||
1044 | if (vga_tryget(pdev, io_state)) { | |
1045 | /* Update the client's locks lists... */ | |
1046 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1047 | if (priv->cards[i].pdev == pdev) { | |
1048 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1049 | priv->cards[i].io_cnt++; | |
1050 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1051 | priv->cards[i].mem_cnt++; | |
1052 | break; | |
1053 | } | |
1054 | } | |
1055 | ret_val = count; | |
1056 | goto done; | |
1057 | } else { | |
1058 | ret_val = -EBUSY; | |
1059 | goto done; | |
1060 | } | |
1061 | ||
1062 | } else if (strncmp(curr_pos, "target ", 7) == 0) { | |
1063 | unsigned int domain, bus, devfn; | |
1064 | struct vga_device *vgadev; | |
1065 | ||
1066 | curr_pos += 7; | |
1067 | remaining -= 7; | |
2d6e9b91 | 1068 | pr_debug("client 0x%p called 'target'\n", priv); |
deb2d2ec | 1069 | /* if target is default */ |
2cc9116c | 1070 | if (!strncmp(curr_pos, "default", 7)) |
deb2d2ec BH |
1071 | pdev = pci_dev_get(vga_default_device()); |
1072 | else { | |
1073 | if (!vga_pci_str_to_vars(curr_pos, remaining, | |
1074 | &domain, &bus, &devfn)) { | |
1075 | ret_val = -EPROTO; | |
1076 | goto done; | |
1077 | } | |
2d6e9b91 | 1078 | pr_debug("vgaarb: %s ==> %x:%x:%x.%x\n", curr_pos, |
773a38db MT |
1079 | domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn)); |
1080 | ||
f85567c8 | 1081 | pdev = pci_get_domain_bus_and_slot(domain, bus, devfn); |
2d6e9b91 | 1082 | pr_debug("vgaarb: pdev %p\n", pdev); |
deb2d2ec | 1083 | if (!pdev) { |
f85567c8 JL |
1084 | pr_err("vgaarb: invalid PCI address %x:%x:%x\n", |
1085 | domain, bus, devfn); | |
deb2d2ec BH |
1086 | ret_val = -ENODEV; |
1087 | goto done; | |
1088 | } | |
1089 | } | |
1090 | ||
1091 | vgadev = vgadev_find(pdev); | |
2d6e9b91 | 1092 | pr_debug("vgaarb: vgadev %p\n", vgadev); |
deb2d2ec | 1093 | if (vgadev == NULL) { |
773a38db | 1094 | pr_err("vgaarb: this pci device is not a vga device\n"); |
deb2d2ec BH |
1095 | pci_dev_put(pdev); |
1096 | ret_val = -ENODEV; | |
1097 | goto done; | |
1098 | } | |
1099 | ||
1100 | priv->target = pdev; | |
1101 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1102 | if (priv->cards[i].pdev == pdev) | |
1103 | break; | |
1104 | if (priv->cards[i].pdev == NULL) { | |
1105 | priv->cards[i].pdev = pdev; | |
1106 | priv->cards[i].io_cnt = 0; | |
1107 | priv->cards[i].mem_cnt = 0; | |
1108 | break; | |
1109 | } | |
1110 | } | |
1111 | if (i == MAX_USER_CARDS) { | |
773a38db MT |
1112 | pr_err("vgaarb: maximum user cards (%d) number reached!\n", |
1113 | MAX_USER_CARDS); | |
deb2d2ec BH |
1114 | pci_dev_put(pdev); |
1115 | /* XXX: which value to return? */ | |
1116 | ret_val = -ENOMEM; | |
1117 | goto done; | |
1118 | } | |
1119 | ||
1120 | ret_val = count; | |
1121 | pci_dev_put(pdev); | |
1122 | goto done; | |
1123 | ||
1124 | ||
1125 | } else if (strncmp(curr_pos, "decodes ", 8) == 0) { | |
1126 | curr_pos += 8; | |
1127 | remaining -= 8; | |
2d6e9b91 | 1128 | pr_debug("vgaarb: client 0x%p called 'decodes'\n", priv); |
deb2d2ec BH |
1129 | |
1130 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1131 | ret_val = -EPROTO; | |
1132 | goto done; | |
1133 | } | |
1134 | pdev = priv->target; | |
1135 | if (priv->target == NULL) { | |
1136 | ret_val = -ENODEV; | |
1137 | goto done; | |
1138 | } | |
1139 | ||
1140 | __vga_set_legacy_decoding(pdev, io_state, true); | |
1141 | ret_val = count; | |
1142 | goto done; | |
1143 | } | |
1144 | /* If we got here, the message written is not part of the protocol! */ | |
1145 | kfree(kbuf); | |
1146 | return -EPROTO; | |
1147 | ||
1148 | done: | |
1149 | kfree(kbuf); | |
1150 | return ret_val; | |
1151 | } | |
1152 | ||
1153 | static unsigned int vga_arb_fpoll(struct file *file, poll_table * wait) | |
1154 | { | |
1155 | struct vga_arb_private *priv = file->private_data; | |
1156 | ||
2d6e9b91 | 1157 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1158 | |
1159 | if (priv == NULL) | |
1160 | return -ENODEV; | |
1161 | poll_wait(file, &vga_wait_queue, wait); | |
1162 | return POLLIN; | |
1163 | } | |
1164 | ||
1165 | static int vga_arb_open(struct inode *inode, struct file *file) | |
1166 | { | |
1167 | struct vga_arb_private *priv; | |
1168 | unsigned long flags; | |
1169 | ||
2d6e9b91 | 1170 | pr_debug("%s\n", __func__); |
deb2d2ec | 1171 | |
f35119d6 | 1172 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); |
deb2d2ec BH |
1173 | if (priv == NULL) |
1174 | return -ENOMEM; | |
deb2d2ec BH |
1175 | spin_lock_init(&priv->lock); |
1176 | file->private_data = priv; | |
1177 | ||
1178 | spin_lock_irqsave(&vga_user_lock, flags); | |
1179 | list_add(&priv->list, &vga_user_list); | |
1180 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1181 | ||
1182 | /* Set the client' lists of locks */ | |
1183 | priv->target = vga_default_device(); /* Maybe this is still null! */ | |
1184 | priv->cards[0].pdev = priv->target; | |
1185 | priv->cards[0].io_cnt = 0; | |
1186 | priv->cards[0].mem_cnt = 0; | |
1187 | ||
1188 | ||
1189 | return 0; | |
1190 | } | |
1191 | ||
1192 | static int vga_arb_release(struct inode *inode, struct file *file) | |
1193 | { | |
1194 | struct vga_arb_private *priv = file->private_data; | |
1195 | struct vga_arb_user_card *uc; | |
1196 | unsigned long flags; | |
1197 | int i; | |
1198 | ||
2d6e9b91 | 1199 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1200 | |
1201 | if (priv == NULL) | |
1202 | return -ENODEV; | |
1203 | ||
1204 | spin_lock_irqsave(&vga_user_lock, flags); | |
1205 | list_del(&priv->list); | |
1206 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1207 | uc = &priv->cards[i]; | |
1208 | if (uc->pdev == NULL) | |
1209 | continue; | |
2d6e9b91 | 1210 | pr_debug("uc->io_cnt == %d, uc->mem_cnt == %d\n", |
deb2d2ec BH |
1211 | uc->io_cnt, uc->mem_cnt); |
1212 | while (uc->io_cnt--) | |
1213 | vga_put(uc->pdev, VGA_RSRC_LEGACY_IO); | |
1214 | while (uc->mem_cnt--) | |
1215 | vga_put(uc->pdev, VGA_RSRC_LEGACY_MEM); | |
1216 | } | |
1217 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1218 | ||
1219 | kfree(priv); | |
1220 | ||
1221 | return 0; | |
1222 | } | |
1223 | ||
1224 | static void vga_arb_device_card_gone(struct pci_dev *pdev) | |
1225 | { | |
1226 | } | |
1227 | ||
1228 | /* | |
1229 | * callback any registered clients to let them know we have a | |
1230 | * change in VGA cards | |
1231 | */ | |
1232 | static void vga_arbiter_notify_clients(void) | |
1233 | { | |
1234 | struct vga_device *vgadev; | |
1235 | unsigned long flags; | |
1236 | uint32_t new_decodes; | |
1237 | bool new_state; | |
1238 | ||
1239 | if (!vga_arbiter_used) | |
1240 | return; | |
1241 | ||
1242 | spin_lock_irqsave(&vga_lock, flags); | |
1243 | list_for_each_entry(vgadev, &vga_list, list) { | |
1244 | if (vga_count > 1) | |
1245 | new_state = false; | |
1246 | else | |
1247 | new_state = true; | |
1248 | if (vgadev->set_vga_decode) { | |
1249 | new_decodes = vgadev->set_vga_decode(vgadev->cookie, new_state); | |
1250 | vga_update_device_decodes(vgadev, new_decodes); | |
1251 | } | |
1252 | } | |
1253 | spin_unlock_irqrestore(&vga_lock, flags); | |
1254 | } | |
1255 | ||
1256 | static int pci_notify(struct notifier_block *nb, unsigned long action, | |
1257 | void *data) | |
1258 | { | |
1259 | struct device *dev = data; | |
1260 | struct pci_dev *pdev = to_pci_dev(dev); | |
1261 | bool notify = false; | |
1262 | ||
2d6e9b91 | 1263 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1264 | |
1265 | /* For now we're only intereted in devices added and removed. I didn't | |
1266 | * test this thing here, so someone needs to double check for the | |
1267 | * cases of hotplugable vga cards. */ | |
1268 | if (action == BUS_NOTIFY_ADD_DEVICE) | |
1269 | notify = vga_arbiter_add_pci_device(pdev); | |
1270 | else if (action == BUS_NOTIFY_DEL_DEVICE) | |
1271 | notify = vga_arbiter_del_pci_device(pdev); | |
1272 | ||
1273 | if (notify) | |
1274 | vga_arbiter_notify_clients(); | |
1275 | return 0; | |
1276 | } | |
1277 | ||
1278 | static struct notifier_block pci_notifier = { | |
1279 | .notifier_call = pci_notify, | |
1280 | }; | |
1281 | ||
1282 | static const struct file_operations vga_arb_device_fops = { | |
1283 | .read = vga_arb_read, | |
1284 | .write = vga_arb_write, | |
1285 | .poll = vga_arb_fpoll, | |
1286 | .open = vga_arb_open, | |
1287 | .release = vga_arb_release, | |
6038f373 | 1288 | .llseek = noop_llseek, |
deb2d2ec BH |
1289 | }; |
1290 | ||
1291 | static struct miscdevice vga_arb_device = { | |
1292 | MISC_DYNAMIC_MINOR, "vga_arbiter", &vga_arb_device_fops | |
1293 | }; | |
1294 | ||
1295 | static int __init vga_arb_device_init(void) | |
1296 | { | |
1297 | int rc; | |
1298 | struct pci_dev *pdev; | |
3448a19d | 1299 | struct vga_device *vgadev; |
deb2d2ec BH |
1300 | |
1301 | rc = misc_register(&vga_arb_device); | |
1302 | if (rc < 0) | |
1303 | pr_err("vgaarb: error %d registering device\n", rc); | |
1304 | ||
1305 | bus_register_notifier(&pci_bus_type, &pci_notifier); | |
1306 | ||
1307 | /* We add all pci devices satisfying vga class in the arbiter by | |
1308 | * default */ | |
1309 | pdev = NULL; | |
1310 | while ((pdev = | |
1311 | pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, | |
1312 | PCI_ANY_ID, pdev)) != NULL) | |
1313 | vga_arbiter_add_pci_device(pdev); | |
1314 | ||
1315 | pr_info("vgaarb: loaded\n"); | |
3448a19d DA |
1316 | |
1317 | list_for_each_entry(vgadev, &vga_list, list) { | |
86fd887b BP |
1318 | #if defined(CONFIG_X86) || defined(CONFIG_IA64) |
1319 | /* Override I/O based detection done by vga_arbiter_add_pci_device() | |
1320 | * as it may take the wrong device (e.g. on Apple system under EFI). | |
1321 | * | |
1322 | * Select the device owning the boot framebuffer if there is one. | |
1323 | */ | |
1324 | resource_size_t start, end; | |
1325 | int i; | |
1326 | ||
1327 | /* Does firmware framebuffer belong to us? */ | |
1328 | for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) { | |
1329 | if (!(pci_resource_flags(vgadev->pdev, i) & IORESOURCE_MEM)) | |
1330 | continue; | |
1331 | ||
1332 | start = pci_resource_start(vgadev->pdev, i); | |
1333 | end = pci_resource_end(vgadev->pdev, i); | |
1334 | ||
1335 | if (!start || !end) | |
1336 | continue; | |
1337 | ||
1338 | if (screen_info.lfb_base < start || | |
1339 | (screen_info.lfb_base + screen_info.lfb_size) >= end) | |
1340 | continue; | |
1341 | if (!vga_default_device()) | |
1342 | pr_info("vgaarb: setting as boot device: PCI:%s\n", | |
1343 | pci_name(vgadev->pdev)); | |
1344 | else if (vgadev->pdev != vga_default_device()) | |
1345 | pr_info("vgaarb: overriding boot device: PCI:%s\n", | |
1346 | pci_name(vgadev->pdev)); | |
1347 | vga_set_default_device(vgadev->pdev); | |
1348 | } | |
1349 | #endif | |
3448a19d DA |
1350 | if (vgadev->bridge_has_one_vga) |
1351 | pr_info("vgaarb: bridge control possible %s\n", pci_name(vgadev->pdev)); | |
1352 | else | |
1353 | pr_info("vgaarb: no bridge control possible %s\n", pci_name(vgadev->pdev)); | |
1354 | } | |
deb2d2ec BH |
1355 | return rc; |
1356 | } | |
1357 | subsys_initcall(vga_arb_device_init); |