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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 | ||
8b7e2e86 TR |
32 | #define pr_fmt(fmt) "vgaarb: " fmt |
33 | ||
deb2d2ec BH |
34 | #include <linux/module.h> |
35 | #include <linux/kernel.h> | |
36 | #include <linux/pci.h> | |
37 | #include <linux/errno.h> | |
38 | #include <linux/init.h> | |
39 | #include <linux/list.h> | |
40 | #include <linux/sched.h> | |
41 | #include <linux/wait.h> | |
42 | #include <linux/spinlock.h> | |
43 | #include <linux/poll.h> | |
44 | #include <linux/miscdevice.h> | |
5a0e3ad6 | 45 | #include <linux/slab.h> |
86fd887b | 46 | #include <linux/screen_info.h> |
deb2d2ec BH |
47 | |
48 | #include <linux/uaccess.h> | |
49 | ||
50 | #include <linux/vgaarb.h> | |
51 | ||
52 | static void vga_arbiter_notify_clients(void); | |
53 | /* | |
54 | * We keep a list of all vga devices in the system to speed | |
55 | * up the various operations of the arbiter | |
56 | */ | |
57 | struct vga_device { | |
58 | struct list_head list; | |
59 | struct pci_dev *pdev; | |
60 | unsigned int decodes; /* what does it decodes */ | |
61 | unsigned int owns; /* what does it owns */ | |
62 | unsigned int locks; /* what does it locks */ | |
63 | unsigned int io_lock_cnt; /* legacy IO lock count */ | |
64 | unsigned int mem_lock_cnt; /* legacy MEM lock count */ | |
65 | unsigned int io_norm_cnt; /* normal IO count */ | |
66 | unsigned int mem_norm_cnt; /* normal MEM count */ | |
3448a19d | 67 | bool bridge_has_one_vga; |
deb2d2ec BH |
68 | /* allow IRQ enable/disable hook */ |
69 | void *cookie; | |
70 | void (*irq_set_state)(void *cookie, bool enable); | |
71 | unsigned int (*set_vga_decode)(void *cookie, bool decode); | |
72 | }; | |
73 | ||
74 | static LIST_HEAD(vga_list); | |
75 | static int vga_count, vga_decode_count; | |
76 | static bool vga_arbiter_used; | |
77 | static DEFINE_SPINLOCK(vga_lock); | |
78 | static DECLARE_WAIT_QUEUE_HEAD(vga_wait_queue); | |
79 | ||
80 | ||
81 | static const char *vga_iostate_to_str(unsigned int iostate) | |
82 | { | |
83 | /* Ignore VGA_RSRC_IO and VGA_RSRC_MEM */ | |
84 | iostate &= VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
85 | switch (iostate) { | |
86 | case VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM: | |
87 | return "io+mem"; | |
88 | case VGA_RSRC_LEGACY_IO: | |
89 | return "io"; | |
90 | case VGA_RSRC_LEGACY_MEM: | |
91 | return "mem"; | |
92 | } | |
93 | return "none"; | |
94 | } | |
95 | ||
96 | static int vga_str_to_iostate(char *buf, int str_size, int *io_state) | |
97 | { | |
98 | /* we could in theory hand out locks on IO and mem | |
99 | * separately to userspace but it can cause deadlocks */ | |
100 | if (strncmp(buf, "none", 4) == 0) { | |
101 | *io_state = VGA_RSRC_NONE; | |
102 | return 1; | |
103 | } | |
104 | ||
105 | /* XXX We're not chekcing the str_size! */ | |
106 | if (strncmp(buf, "io+mem", 6) == 0) | |
107 | goto both; | |
108 | else if (strncmp(buf, "io", 2) == 0) | |
109 | goto both; | |
110 | else if (strncmp(buf, "mem", 3) == 0) | |
111 | goto both; | |
112 | return 0; | |
113 | both: | |
114 | *io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
115 | return 1; | |
116 | } | |
117 | ||
deb2d2ec BH |
118 | /* this is only used a cookie - it should not be dereferenced */ |
119 | static struct pci_dev *vga_default; | |
deb2d2ec BH |
120 | |
121 | static void vga_arb_device_card_gone(struct pci_dev *pdev); | |
122 | ||
123 | /* Find somebody in our list */ | |
124 | static struct vga_device *vgadev_find(struct pci_dev *pdev) | |
125 | { | |
126 | struct vga_device *vgadev; | |
127 | ||
128 | list_for_each_entry(vgadev, &vga_list, list) | |
129 | if (pdev == vgadev->pdev) | |
130 | return vgadev; | |
131 | return NULL; | |
132 | } | |
133 | ||
b754b35b DV |
134 | /** |
135 | * vga_default_device - return the default VGA device, for vgacon | |
136 | * | |
137 | * This can be defined by the platform. The default implementation | |
138 | * is rather dumb and will probably only work properly on single | |
139 | * vga card setups and/or x86 platforms. | |
140 | * | |
141 | * If your VGA default device is not PCI, you'll have to return | |
142 | * NULL here. In this case, I assume it will not conflict with | |
143 | * any PCI card. If this is not true, I'll have to define two archs | |
144 | * hooks for enabling/disabling the VGA default device if that is | |
145 | * possible. This may be a problem with real _ISA_ VGA cards, in | |
146 | * addition to a PCI one. I don't know at this point how to deal | |
147 | * with that card. Can theirs IOs be disabled at all ? If not, then | |
148 | * I suppose it's a matter of having the proper arch hook telling | |
149 | * us about it, so we basically never allow anybody to succeed a | |
150 | * vga_get()... | |
151 | */ | |
deb2d2ec BH |
152 | struct pci_dev *vga_default_device(void) |
153 | { | |
154 | return vga_default; | |
155 | } | |
1b23170a MG |
156 | EXPORT_SYMBOL_GPL(vga_default_device); |
157 | ||
1a39b310 MG |
158 | void vga_set_default_device(struct pci_dev *pdev) |
159 | { | |
84544a1d YL |
160 | if (vga_default == pdev) |
161 | return; | |
162 | ||
163 | pci_dev_put(vga_default); | |
164 | vga_default = pci_dev_get(pdev); | |
1a39b310 | 165 | } |
deb2d2ec BH |
166 | |
167 | static inline void vga_irq_set_state(struct vga_device *vgadev, bool state) | |
168 | { | |
169 | if (vgadev->irq_set_state) | |
170 | vgadev->irq_set_state(vgadev->cookie, state); | |
171 | } | |
172 | ||
173 | ||
174 | /* If we don't ever use VGA arb we should avoid | |
175 | turning off anything anywhere due to old X servers getting | |
176 | confused about the boot device not being VGA */ | |
177 | static void vga_check_first_use(void) | |
178 | { | |
179 | /* we should inform all GPUs in the system that | |
25985edc | 180 | * VGA arb has occurred and to try and disable resources |
deb2d2ec BH |
181 | * if they can */ |
182 | if (!vga_arbiter_used) { | |
183 | vga_arbiter_used = true; | |
184 | vga_arbiter_notify_clients(); | |
185 | } | |
186 | } | |
187 | ||
188 | static struct vga_device *__vga_tryget(struct vga_device *vgadev, | |
189 | unsigned int rsrc) | |
190 | { | |
191 | unsigned int wants, legacy_wants, match; | |
192 | struct vga_device *conflict; | |
193 | unsigned int pci_bits; | |
3448a19d DA |
194 | u32 flags = 0; |
195 | ||
deb2d2ec BH |
196 | /* Account for "normal" resources to lock. If we decode the legacy, |
197 | * counterpart, we need to request it as well | |
198 | */ | |
199 | if ((rsrc & VGA_RSRC_NORMAL_IO) && | |
200 | (vgadev->decodes & VGA_RSRC_LEGACY_IO)) | |
201 | rsrc |= VGA_RSRC_LEGACY_IO; | |
202 | if ((rsrc & VGA_RSRC_NORMAL_MEM) && | |
203 | (vgadev->decodes & VGA_RSRC_LEGACY_MEM)) | |
204 | rsrc |= VGA_RSRC_LEGACY_MEM; | |
205 | ||
2d6e9b91 TV |
206 | pr_debug("%s: %d\n", __func__, rsrc); |
207 | pr_debug("%s: owns: %d\n", __func__, vgadev->owns); | |
deb2d2ec BH |
208 | |
209 | /* Check what resources we need to acquire */ | |
210 | wants = rsrc & ~vgadev->owns; | |
211 | ||
212 | /* We already own everything, just mark locked & bye bye */ | |
213 | if (wants == 0) | |
214 | goto lock_them; | |
215 | ||
216 | /* We don't need to request a legacy resource, we just enable | |
217 | * appropriate decoding and go | |
218 | */ | |
219 | legacy_wants = wants & VGA_RSRC_LEGACY_MASK; | |
220 | if (legacy_wants == 0) | |
221 | goto enable_them; | |
222 | ||
223 | /* Ok, we don't, let's find out how we need to kick off */ | |
224 | list_for_each_entry(conflict, &vga_list, list) { | |
225 | unsigned int lwants = legacy_wants; | |
226 | unsigned int change_bridge = 0; | |
227 | ||
228 | /* Don't conflict with myself */ | |
229 | if (vgadev == conflict) | |
230 | continue; | |
231 | ||
232 | /* Check if the architecture allows a conflict between those | |
233 | * 2 devices or if they are on separate domains | |
234 | */ | |
235 | if (!vga_conflicts(vgadev->pdev, conflict->pdev)) | |
236 | continue; | |
237 | ||
238 | /* We have a possible conflict. before we go further, we must | |
239 | * check if we sit on the same bus as the conflicting device. | |
240 | * if we don't, then we must tie both IO and MEM resources | |
241 | * together since there is only a single bit controlling | |
242 | * VGA forwarding on P2P bridges | |
243 | */ | |
244 | if (vgadev->pdev->bus != conflict->pdev->bus) { | |
245 | change_bridge = 1; | |
246 | lwants = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
247 | } | |
248 | ||
249 | /* Check if the guy has a lock on the resource. If he does, | |
250 | * return the conflicting entry | |
251 | */ | |
252 | if (conflict->locks & lwants) | |
253 | return conflict; | |
254 | ||
4e4e7dc5 AW |
255 | /* Ok, now check if it owns the resource we want. We can |
256 | * lock resources that are not decoded, therefore a device | |
257 | * can own resources it doesn't decode. | |
deb2d2ec | 258 | */ |
deb2d2ec BH |
259 | match = lwants & conflict->owns; |
260 | if (!match) | |
261 | continue; | |
262 | ||
263 | /* looks like he doesn't have a lock, we can steal | |
264 | * them from him | |
265 | */ | |
deb2d2ec | 266 | |
3448a19d | 267 | flags = 0; |
deb2d2ec | 268 | pci_bits = 0; |
deb2d2ec | 269 | |
4e4e7dc5 AW |
270 | /* If we can't control legacy resources via the bridge, we |
271 | * also need to disable normal decoding. | |
272 | */ | |
3448a19d | 273 | if (!conflict->bridge_has_one_vga) { |
4e4e7dc5 | 274 | if ((match & conflict->decodes) & VGA_RSRC_LEGACY_MEM) |
3448a19d | 275 | pci_bits |= PCI_COMMAND_MEMORY; |
4e4e7dc5 | 276 | if ((match & conflict->decodes) & VGA_RSRC_LEGACY_IO) |
3448a19d | 277 | pci_bits |= PCI_COMMAND_IO; |
4e4e7dc5 AW |
278 | |
279 | if (pci_bits) { | |
280 | vga_irq_set_state(conflict, false); | |
281 | flags |= PCI_VGA_STATE_CHANGE_DECODES; | |
282 | } | |
3448a19d DA |
283 | } |
284 | ||
285 | if (change_bridge) | |
286 | flags |= PCI_VGA_STATE_CHANGE_BRIDGE; | |
287 | ||
288 | pci_set_vga_state(conflict->pdev, false, pci_bits, flags); | |
f22d776f | 289 | conflict->owns &= ~match; |
4e4e7dc5 AW |
290 | |
291 | /* If we disabled normal decoding, reflect it in owns */ | |
292 | if (pci_bits & PCI_COMMAND_MEMORY) | |
deb2d2ec | 293 | conflict->owns &= ~VGA_RSRC_NORMAL_MEM; |
4e4e7dc5 | 294 | if (pci_bits & PCI_COMMAND_IO) |
deb2d2ec BH |
295 | conflict->owns &= ~VGA_RSRC_NORMAL_IO; |
296 | } | |
297 | ||
298 | enable_them: | |
299 | /* ok dude, we got it, everybody conflicting has been disabled, let's | |
4e4e7dc5 AW |
300 | * enable us. Mark any bits in "owns" regardless of whether we |
301 | * decoded them. We can lock resources we don't decode, therefore | |
302 | * we must track them via "owns". | |
deb2d2ec | 303 | */ |
3448a19d | 304 | flags = 0; |
deb2d2ec | 305 | pci_bits = 0; |
deb2d2ec | 306 | |
3448a19d DA |
307 | if (!vgadev->bridge_has_one_vga) { |
308 | flags |= PCI_VGA_STATE_CHANGE_DECODES; | |
309 | if (wants & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) | |
310 | pci_bits |= PCI_COMMAND_MEMORY; | |
311 | if (wants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) | |
312 | pci_bits |= PCI_COMMAND_IO; | |
313 | } | |
4e4e7dc5 | 314 | if (wants & VGA_RSRC_LEGACY_MASK) |
3448a19d DA |
315 | flags |= PCI_VGA_STATE_CHANGE_BRIDGE; |
316 | ||
317 | pci_set_vga_state(vgadev->pdev, true, pci_bits, flags); | |
318 | ||
5d90ccf9 | 319 | if (!vgadev->bridge_has_one_vga) |
3448a19d | 320 | vga_irq_set_state(vgadev, true); |
5d90ccf9 | 321 | |
4e4e7dc5 | 322 | vgadev->owns |= wants; |
deb2d2ec BH |
323 | lock_them: |
324 | vgadev->locks |= (rsrc & VGA_RSRC_LEGACY_MASK); | |
325 | if (rsrc & VGA_RSRC_LEGACY_IO) | |
326 | vgadev->io_lock_cnt++; | |
327 | if (rsrc & VGA_RSRC_LEGACY_MEM) | |
328 | vgadev->mem_lock_cnt++; | |
329 | if (rsrc & VGA_RSRC_NORMAL_IO) | |
330 | vgadev->io_norm_cnt++; | |
331 | if (rsrc & VGA_RSRC_NORMAL_MEM) | |
332 | vgadev->mem_norm_cnt++; | |
333 | ||
334 | return NULL; | |
335 | } | |
336 | ||
337 | static void __vga_put(struct vga_device *vgadev, unsigned int rsrc) | |
338 | { | |
339 | unsigned int old_locks = vgadev->locks; | |
340 | ||
2d6e9b91 | 341 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
342 | |
343 | /* Update our counters, and account for equivalent legacy resources | |
344 | * if we decode them | |
345 | */ | |
346 | if ((rsrc & VGA_RSRC_NORMAL_IO) && vgadev->io_norm_cnt > 0) { | |
347 | vgadev->io_norm_cnt--; | |
348 | if (vgadev->decodes & VGA_RSRC_LEGACY_IO) | |
349 | rsrc |= VGA_RSRC_LEGACY_IO; | |
350 | } | |
351 | if ((rsrc & VGA_RSRC_NORMAL_MEM) && vgadev->mem_norm_cnt > 0) { | |
352 | vgadev->mem_norm_cnt--; | |
353 | if (vgadev->decodes & VGA_RSRC_LEGACY_MEM) | |
354 | rsrc |= VGA_RSRC_LEGACY_MEM; | |
355 | } | |
356 | if ((rsrc & VGA_RSRC_LEGACY_IO) && vgadev->io_lock_cnt > 0) | |
357 | vgadev->io_lock_cnt--; | |
358 | if ((rsrc & VGA_RSRC_LEGACY_MEM) && vgadev->mem_lock_cnt > 0) | |
359 | vgadev->mem_lock_cnt--; | |
360 | ||
361 | /* Just clear lock bits, we do lazy operations so we don't really | |
362 | * have to bother about anything else at this point | |
363 | */ | |
364 | if (vgadev->io_lock_cnt == 0) | |
365 | vgadev->locks &= ~VGA_RSRC_LEGACY_IO; | |
366 | if (vgadev->mem_lock_cnt == 0) | |
367 | vgadev->locks &= ~VGA_RSRC_LEGACY_MEM; | |
368 | ||
369 | /* Kick the wait queue in case somebody was waiting if we actually | |
370 | * released something | |
371 | */ | |
372 | if (old_locks != vgadev->locks) | |
373 | wake_up_all(&vga_wait_queue); | |
374 | } | |
375 | ||
b754b35b DV |
376 | /** |
377 | * vga_get - acquire & locks VGA resources | |
378 | * @pdev: pci device of the VGA card or NULL for the system default | |
379 | * @rsrc: bit mask of resources to acquire and lock | |
380 | * @interruptible: blocking should be interruptible by signals ? | |
381 | * | |
382 | * This function acquires VGA resources for the given card and mark those | |
383 | * resources locked. If the resource requested are "normal" (and not legacy) | |
384 | * resources, the arbiter will first check whether the card is doing legacy | |
385 | * decoding for that type of resource. If yes, the lock is "converted" into a | |
386 | * legacy resource lock. | |
387 | * | |
388 | * The arbiter will first look for all VGA cards that might conflict and disable | |
389 | * their IOs and/or Memory access, including VGA forwarding on P2P bridges if | |
390 | * necessary, so that the requested resources can be used. Then, the card is | |
391 | * marked as locking these resources and the IO and/or Memory accesses are | |
392 | * enabled on the card (including VGA forwarding on parent P2P bridges if any). | |
393 | * | |
394 | * This function will block if some conflicting card is already locking one of | |
395 | * the required resources (or any resource on a different bus segment, since P2P | |
396 | * bridges don't differentiate VGA memory and IO afaik). You can indicate | |
397 | * whether this blocking should be interruptible by a signal (for userland | |
398 | * interface) or not. | |
399 | * | |
400 | * Must not be called at interrupt time or in atomic context. If the card | |
401 | * already owns the resources, the function succeeds. Nested calls are | |
402 | * supported (a per-resource counter is maintained) | |
403 | * | |
404 | * On success, release the VGA resource again with vga_put(). | |
405 | * | |
406 | * Returns: | |
407 | * | |
408 | * 0 on success, negative error code on failure. | |
409 | */ | |
deb2d2ec BH |
410 | int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible) |
411 | { | |
412 | struct vga_device *vgadev, *conflict; | |
413 | unsigned long flags; | |
414 | wait_queue_t wait; | |
415 | int rc = 0; | |
416 | ||
417 | vga_check_first_use(); | |
418 | /* The one who calls us should check for this, but lets be sure... */ | |
419 | if (pdev == NULL) | |
420 | pdev = vga_default_device(); | |
421 | if (pdev == NULL) | |
422 | return 0; | |
423 | ||
424 | for (;;) { | |
425 | spin_lock_irqsave(&vga_lock, flags); | |
426 | vgadev = vgadev_find(pdev); | |
427 | if (vgadev == NULL) { | |
428 | spin_unlock_irqrestore(&vga_lock, flags); | |
429 | rc = -ENODEV; | |
430 | break; | |
431 | } | |
432 | conflict = __vga_tryget(vgadev, rsrc); | |
433 | spin_unlock_irqrestore(&vga_lock, flags); | |
434 | if (conflict == NULL) | |
435 | break; | |
436 | ||
437 | ||
438 | /* We have a conflict, we wait until somebody kicks the | |
439 | * work queue. Currently we have one work queue that we | |
440 | * kick each time some resources are released, but it would | |
441 | * be fairly easy to have a per device one so that we only | |
442 | * need to attach to the conflicting device | |
443 | */ | |
444 | init_waitqueue_entry(&wait, current); | |
445 | add_wait_queue(&vga_wait_queue, &wait); | |
446 | set_current_state(interruptible ? | |
447 | TASK_INTERRUPTIBLE : | |
448 | TASK_UNINTERRUPTIBLE); | |
9f5bd308 KS |
449 | if (interruptible && signal_pending(current)) { |
450 | __set_current_state(TASK_RUNNING); | |
451 | remove_wait_queue(&vga_wait_queue, &wait); | |
452 | rc = -ERESTARTSYS; | |
deb2d2ec BH |
453 | break; |
454 | } | |
455 | schedule(); | |
456 | remove_wait_queue(&vga_wait_queue, &wait); | |
deb2d2ec BH |
457 | } |
458 | return rc; | |
459 | } | |
460 | EXPORT_SYMBOL(vga_get); | |
461 | ||
b754b35b DV |
462 | /** |
463 | * vga_tryget - try to acquire & lock legacy VGA resources | |
464 | * @pdev: pci devivce of VGA card or NULL for system default | |
465 | * @rsrc: bit mask of resources to acquire and lock | |
466 | * | |
467 | * This function performs the same operation as vga_get(), but will return an | |
468 | * error (-EBUSY) instead of blocking if the resources are already locked by | |
469 | * another card. It can be called in any context | |
470 | * | |
471 | * On success, release the VGA resource again with vga_put(). | |
472 | * | |
473 | * Returns: | |
474 | * | |
475 | * 0 on success, negative error code on failure. | |
476 | */ | |
deb2d2ec BH |
477 | int vga_tryget(struct pci_dev *pdev, unsigned int rsrc) |
478 | { | |
479 | struct vga_device *vgadev; | |
480 | unsigned long flags; | |
481 | int rc = 0; | |
482 | ||
483 | vga_check_first_use(); | |
484 | ||
485 | /* The one who calls us should check for this, but lets be sure... */ | |
486 | if (pdev == NULL) | |
487 | pdev = vga_default_device(); | |
488 | if (pdev == NULL) | |
489 | return 0; | |
490 | spin_lock_irqsave(&vga_lock, flags); | |
491 | vgadev = vgadev_find(pdev); | |
492 | if (vgadev == NULL) { | |
493 | rc = -ENODEV; | |
494 | goto bail; | |
495 | } | |
496 | if (__vga_tryget(vgadev, rsrc)) | |
497 | rc = -EBUSY; | |
498 | bail: | |
499 | spin_unlock_irqrestore(&vga_lock, flags); | |
500 | return rc; | |
501 | } | |
502 | EXPORT_SYMBOL(vga_tryget); | |
503 | ||
b754b35b DV |
504 | /** |
505 | * vga_put - release lock on legacy VGA resources | |
506 | * @pdev: pci device of VGA card or NULL for system default | |
507 | * @rsrc: but mask of resource to release | |
508 | * | |
509 | * This fuction releases resources previously locked by vga_get() or | |
510 | * vga_tryget(). The resources aren't disabled right away, so that a subsequence | |
511 | * vga_get() on the same card will succeed immediately. Resources have a | |
512 | * counter, so locks are only released if the counter reaches 0. | |
513 | */ | |
deb2d2ec BH |
514 | void vga_put(struct pci_dev *pdev, unsigned int rsrc) |
515 | { | |
516 | struct vga_device *vgadev; | |
517 | unsigned long flags; | |
518 | ||
519 | /* The one who calls us should check for this, but lets be sure... */ | |
520 | if (pdev == NULL) | |
521 | pdev = vga_default_device(); | |
522 | if (pdev == NULL) | |
523 | return; | |
524 | spin_lock_irqsave(&vga_lock, flags); | |
525 | vgadev = vgadev_find(pdev); | |
526 | if (vgadev == NULL) | |
527 | goto bail; | |
528 | __vga_put(vgadev, rsrc); | |
529 | bail: | |
530 | spin_unlock_irqrestore(&vga_lock, flags); | |
531 | } | |
532 | EXPORT_SYMBOL(vga_put); | |
533 | ||
5d90ccf9 TR |
534 | /* |
535 | * Rules for using a bridge to control a VGA descendant decoding: if a bridge | |
536 | * has only one VGA descendant then it can be used to control the VGA routing | |
537 | * for that device. It should always use the bridge closest to the device to | |
538 | * control it. If a bridge has a direct VGA descendant, but also have a sub- | |
539 | * bridge VGA descendant then we cannot use that bridge to control the direct | |
540 | * VGA descendant. So for every device we register, we need to iterate all | |
541 | * its parent bridges so we can invalidate any devices using them properly. | |
542 | */ | |
3448a19d DA |
543 | static void vga_arbiter_check_bridge_sharing(struct vga_device *vgadev) |
544 | { | |
545 | struct vga_device *same_bridge_vgadev; | |
546 | struct pci_bus *new_bus, *bus; | |
547 | struct pci_dev *new_bridge, *bridge; | |
548 | ||
549 | vgadev->bridge_has_one_vga = true; | |
550 | ||
551 | if (list_empty(&vga_list)) | |
552 | return; | |
553 | ||
554 | /* okay iterate the new devices bridge hierarachy */ | |
555 | new_bus = vgadev->pdev->bus; | |
556 | while (new_bus) { | |
557 | new_bridge = new_bus->self; | |
558 | ||
f6252114 DA |
559 | /* go through list of devices already registered */ |
560 | list_for_each_entry(same_bridge_vgadev, &vga_list, list) { | |
561 | bus = same_bridge_vgadev->pdev->bus; | |
562 | bridge = bus->self; | |
563 | ||
564 | /* see if the share a bridge with this device */ | |
565 | if (new_bridge == bridge) { | |
5d90ccf9 TR |
566 | /* |
567 | * If their direct parent bridge is the same | |
568 | * as any bridge of this device then it can't | |
569 | * be used for that device. | |
570 | */ | |
f6252114 DA |
571 | same_bridge_vgadev->bridge_has_one_vga = false; |
572 | } | |
3448a19d | 573 | |
5d90ccf9 TR |
574 | /* |
575 | * Now iterate the previous devices bridge hierarchy. | |
576 | * If the new devices parent bridge is in the other | |
577 | * devices hierarchy then we can't use it to control | |
578 | * this device | |
579 | */ | |
f6252114 DA |
580 | while (bus) { |
581 | bridge = bus->self; | |
5d90ccf9 TR |
582 | |
583 | if (bridge && bridge == vgadev->pdev->bus->self) | |
584 | vgadev->bridge_has_one_vga = false; | |
585 | ||
f6252114 | 586 | bus = bus->parent; |
3448a19d DA |
587 | } |
588 | } | |
589 | new_bus = new_bus->parent; | |
590 | } | |
591 | } | |
592 | ||
deb2d2ec BH |
593 | /* |
594 | * Currently, we assume that the "initial" setup of the system is | |
595 | * not sane, that is we come up with conflicting devices and let | |
596 | * the arbiter's client decides if devices decodes or not legacy | |
597 | * things. | |
598 | */ | |
599 | static bool vga_arbiter_add_pci_device(struct pci_dev *pdev) | |
600 | { | |
601 | struct vga_device *vgadev; | |
602 | unsigned long flags; | |
603 | struct pci_bus *bus; | |
604 | struct pci_dev *bridge; | |
605 | u16 cmd; | |
606 | ||
607 | /* Only deal with VGA class devices */ | |
608 | if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA) | |
609 | return false; | |
610 | ||
611 | /* Allocate structure */ | |
945ef5bb | 612 | vgadev = kzalloc(sizeof(struct vga_device), GFP_KERNEL); |
deb2d2ec | 613 | if (vgadev == NULL) { |
8b7e2e86 | 614 | pr_err("failed to allocate pci device\n"); |
5d90ccf9 TR |
615 | /* |
616 | * What to do on allocation failure ? For now, let's just do | |
617 | * nothing, I'm not sure there is anything saner to be done. | |
deb2d2ec BH |
618 | */ |
619 | return false; | |
620 | } | |
621 | ||
deb2d2ec BH |
622 | /* Take lock & check for duplicates */ |
623 | spin_lock_irqsave(&vga_lock, flags); | |
624 | if (vgadev_find(pdev) != NULL) { | |
625 | BUG_ON(1); | |
626 | goto fail; | |
627 | } | |
628 | vgadev->pdev = pdev; | |
629 | ||
630 | /* By default, assume we decode everything */ | |
631 | vgadev->decodes = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM | | |
632 | VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM; | |
633 | ||
634 | /* by default mark it as decoding */ | |
635 | vga_decode_count++; | |
636 | /* Mark that we "own" resources based on our enables, we will | |
637 | * clear that below if the bridge isn't forwarding | |
638 | */ | |
639 | pci_read_config_word(pdev, PCI_COMMAND, &cmd); | |
640 | if (cmd & PCI_COMMAND_IO) | |
641 | vgadev->owns |= VGA_RSRC_LEGACY_IO; | |
642 | if (cmd & PCI_COMMAND_MEMORY) | |
643 | vgadev->owns |= VGA_RSRC_LEGACY_MEM; | |
644 | ||
645 | /* Check if VGA cycles can get down to us */ | |
646 | bus = pdev->bus; | |
647 | while (bus) { | |
648 | bridge = bus->self; | |
649 | if (bridge) { | |
650 | u16 l; | |
5d90ccf9 TR |
651 | |
652 | pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, &l); | |
deb2d2ec BH |
653 | if (!(l & PCI_BRIDGE_CTL_VGA)) { |
654 | vgadev->owns = 0; | |
655 | break; | |
656 | } | |
657 | } | |
658 | bus = bus->parent; | |
659 | } | |
660 | ||
661 | /* Deal with VGA default device. Use first enabled one | |
662 | * by default if arch doesn't have it's own hook | |
663 | */ | |
deb2d2ec | 664 | if (vga_default == NULL && |
86fd887b | 665 | ((vgadev->owns & VGA_RSRC_LEGACY_MASK) == VGA_RSRC_LEGACY_MASK)) { |
8b7e2e86 | 666 | pr_info("setting as boot device: PCI:%s\n", pci_name(pdev)); |
84544a1d | 667 | vga_set_default_device(pdev); |
86fd887b | 668 | } |
deb2d2ec | 669 | |
3448a19d DA |
670 | vga_arbiter_check_bridge_sharing(vgadev); |
671 | ||
deb2d2ec BH |
672 | /* Add to the list */ |
673 | list_add(&vgadev->list, &vga_list); | |
674 | vga_count++; | |
8b7e2e86 | 675 | pr_info("device added: PCI:%s,decodes=%s,owns=%s,locks=%s\n", |
deb2d2ec BH |
676 | pci_name(pdev), |
677 | vga_iostate_to_str(vgadev->decodes), | |
678 | vga_iostate_to_str(vgadev->owns), | |
679 | vga_iostate_to_str(vgadev->locks)); | |
680 | ||
681 | spin_unlock_irqrestore(&vga_lock, flags); | |
682 | return true; | |
683 | fail: | |
684 | spin_unlock_irqrestore(&vga_lock, flags); | |
685 | kfree(vgadev); | |
686 | return false; | |
687 | } | |
688 | ||
689 | static bool vga_arbiter_del_pci_device(struct pci_dev *pdev) | |
690 | { | |
691 | struct vga_device *vgadev; | |
692 | unsigned long flags; | |
693 | bool ret = true; | |
694 | ||
695 | spin_lock_irqsave(&vga_lock, flags); | |
696 | vgadev = vgadev_find(pdev); | |
697 | if (vgadev == NULL) { | |
698 | ret = false; | |
699 | goto bail; | |
700 | } | |
701 | ||
84544a1d YL |
702 | if (vga_default == pdev) |
703 | vga_set_default_device(NULL); | |
deb2d2ec BH |
704 | |
705 | if (vgadev->decodes & (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)) | |
706 | vga_decode_count--; | |
707 | ||
708 | /* Remove entry from list */ | |
709 | list_del(&vgadev->list); | |
710 | vga_count--; | |
711 | /* Notify userland driver that the device is gone so it discards | |
712 | * it's copies of the pci_dev pointer | |
713 | */ | |
714 | vga_arb_device_card_gone(pdev); | |
715 | ||
716 | /* Wake up all possible waiters */ | |
717 | wake_up_all(&vga_wait_queue); | |
718 | bail: | |
719 | spin_unlock_irqrestore(&vga_lock, flags); | |
720 | kfree(vgadev); | |
721 | return ret; | |
722 | } | |
723 | ||
724 | /* this is called with the lock */ | |
725 | static inline void vga_update_device_decodes(struct vga_device *vgadev, | |
726 | int new_decodes) | |
727 | { | |
5c0f6ee7 | 728 | int old_decodes, decodes_removed, decodes_unlocked; |
deb2d2ec BH |
729 | |
730 | old_decodes = vgadev->decodes; | |
5c0f6ee7 AW |
731 | decodes_removed = ~new_decodes & old_decodes; |
732 | decodes_unlocked = vgadev->locks & decodes_removed; | |
deb2d2ec BH |
733 | vgadev->decodes = new_decodes; |
734 | ||
8b7e2e86 | 735 | pr_info("device changed decodes: PCI:%s,olddecodes=%s,decodes=%s:owns=%s\n", |
deb2d2ec BH |
736 | pci_name(vgadev->pdev), |
737 | vga_iostate_to_str(old_decodes), | |
738 | vga_iostate_to_str(vgadev->decodes), | |
739 | vga_iostate_to_str(vgadev->owns)); | |
740 | ||
5c0f6ee7 AW |
741 | /* if we removed locked decodes, lock count goes to zero, and release */ |
742 | if (decodes_unlocked) { | |
743 | if (decodes_unlocked & VGA_RSRC_LEGACY_IO) | |
744 | vgadev->io_lock_cnt = 0; | |
745 | if (decodes_unlocked & VGA_RSRC_LEGACY_MEM) | |
746 | vgadev->mem_lock_cnt = 0; | |
747 | __vga_put(vgadev, decodes_unlocked); | |
deb2d2ec BH |
748 | } |
749 | ||
750 | /* change decodes counter */ | |
5c0f6ee7 AW |
751 | if (old_decodes & VGA_RSRC_LEGACY_MASK && |
752 | !(new_decodes & VGA_RSRC_LEGACY_MASK)) | |
753 | vga_decode_count--; | |
754 | if (!(old_decodes & VGA_RSRC_LEGACY_MASK) && | |
755 | new_decodes & VGA_RSRC_LEGACY_MASK) | |
756 | vga_decode_count++; | |
8b7e2e86 | 757 | pr_debug("decoding count now is: %d\n", vga_decode_count); |
deb2d2ec BH |
758 | } |
759 | ||
5d90ccf9 TR |
760 | static void __vga_set_legacy_decoding(struct pci_dev *pdev, |
761 | unsigned int decodes, | |
762 | bool userspace) | |
deb2d2ec BH |
763 | { |
764 | struct vga_device *vgadev; | |
765 | unsigned long flags; | |
766 | ||
767 | decodes &= VGA_RSRC_LEGACY_MASK; | |
768 | ||
769 | spin_lock_irqsave(&vga_lock, flags); | |
770 | vgadev = vgadev_find(pdev); | |
771 | if (vgadev == NULL) | |
772 | goto bail; | |
773 | ||
774 | /* don't let userspace futz with kernel driver decodes */ | |
775 | if (userspace && vgadev->set_vga_decode) | |
776 | goto bail; | |
777 | ||
778 | /* update the device decodes + counter */ | |
779 | vga_update_device_decodes(vgadev, decodes); | |
780 | ||
781 | /* XXX if somebody is going from "doesn't decode" to "decodes" state | |
782 | * here, additional care must be taken as we may have pending owner | |
783 | * ship of non-legacy region ... | |
784 | */ | |
785 | bail: | |
786 | spin_unlock_irqrestore(&vga_lock, flags); | |
787 | } | |
788 | ||
789 | void vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes) | |
790 | { | |
791 | __vga_set_legacy_decoding(pdev, decodes, false); | |
792 | } | |
793 | EXPORT_SYMBOL(vga_set_legacy_decoding); | |
794 | ||
b754b35b DV |
795 | /** |
796 | * vga_client_register - register or unregister a VGA arbitration client | |
797 | * @pdev: pci device of the VGA client | |
798 | * @cookie: client cookie to be used in callbacks | |
799 | * @irq_set_state: irq state change callback | |
800 | * @set_vga_decode: vga decode change callback | |
801 | * | |
802 | * Clients have two callback mechanisms they can use. | |
803 | * | |
804 | * @irq_set_state callback: If a client can't disable its GPUs VGA | |
805 | * resources, then we need to be able to ask it to turn off its irqs when we | |
806 | * turn off its mem and io decoding. | |
807 | * | |
808 | * @set_vga_decode callback: If a client can disable its GPU VGA resource, it | |
809 | * will get a callback from this to set the encode/decode state. | |
810 | * | |
811 | * Rationale: we cannot disable VGA decode resources unconditionally some single | |
812 | * GPU laptops seem to require ACPI or BIOS access to the VGA registers to | |
813 | * control things like backlights etc. Hopefully newer multi-GPU laptops do | |
814 | * something saner, and desktops won't have any special ACPI for this. The | |
815 | * driver will get a callback when VGA arbitration is first used by userspace | |
816 | * since some older X servers have issues. | |
817 | * | |
818 | * This function does not check whether a client for @pdev has been registered | |
819 | * already. | |
820 | * | |
821 | * To unregister just call this function with @irq_set_state and @set_vga_decode | |
822 | * both set to NULL for the same @pdev as originally used to register them. | |
823 | * | |
824 | * Returns: 0 on success, -1 on failure | |
825 | */ | |
deb2d2ec BH |
826 | int vga_client_register(struct pci_dev *pdev, void *cookie, |
827 | void (*irq_set_state)(void *cookie, bool state), | |
5d90ccf9 TR |
828 | unsigned int (*set_vga_decode)(void *cookie, |
829 | bool decode)) | |
deb2d2ec | 830 | { |
934f992c | 831 | int ret = -ENODEV; |
deb2d2ec BH |
832 | struct vga_device *vgadev; |
833 | unsigned long flags; | |
834 | ||
835 | spin_lock_irqsave(&vga_lock, flags); | |
836 | vgadev = vgadev_find(pdev); | |
837 | if (!vgadev) | |
838 | goto bail; | |
839 | ||
840 | vgadev->irq_set_state = irq_set_state; | |
841 | vgadev->set_vga_decode = set_vga_decode; | |
842 | vgadev->cookie = cookie; | |
843 | ret = 0; | |
844 | ||
845 | bail: | |
846 | spin_unlock_irqrestore(&vga_lock, flags); | |
847 | return ret; | |
848 | ||
849 | } | |
850 | EXPORT_SYMBOL(vga_client_register); | |
851 | ||
852 | /* | |
853 | * Char driver implementation | |
854 | * | |
855 | * Semantics is: | |
856 | * | |
857 | * open : open user instance of the arbitrer. by default, it's | |
858 | * attached to the default VGA device of the system. | |
859 | * | |
860 | * close : close user instance, release locks | |
861 | * | |
862 | * read : return a string indicating the status of the target. | |
863 | * an IO state string is of the form {io,mem,io+mem,none}, | |
864 | * mc and ic are respectively mem and io lock counts (for | |
865 | * debugging/diagnostic only). "decodes" indicate what the | |
866 | * card currently decodes, "owns" indicates what is currently | |
867 | * enabled on it, and "locks" indicates what is locked by this | |
868 | * card. If the card is unplugged, we get "invalid" then for | |
869 | * card_ID and an -ENODEV error is returned for any command | |
870 | * until a new card is targeted | |
871 | * | |
872 | * "<card_ID>,decodes=<io_state>,owns=<io_state>,locks=<io_state> (ic,mc)" | |
873 | * | |
874 | * write : write a command to the arbiter. List of commands is: | |
875 | * | |
876 | * target <card_ID> : switch target to card <card_ID> (see below) | |
877 | * lock <io_state> : acquires locks on target ("none" is invalid io_state) | |
878 | * trylock <io_state> : non-blocking acquire locks on target | |
879 | * unlock <io_state> : release locks on target | |
880 | * unlock all : release all locks on target held by this user | |
881 | * decodes <io_state> : set the legacy decoding attributes for the card | |
882 | * | |
883 | * poll : event if something change on any card (not just the target) | |
884 | * | |
885 | * card_ID is of the form "PCI:domain:bus:dev.fn". It can be set to "default" | |
886 | * to go back to the system default card (TODO: not implemented yet). | |
887 | * Currently, only PCI is supported as a prefix, but the userland API may | |
888 | * support other bus types in the future, even if the current kernel | |
889 | * implementation doesn't. | |
890 | * | |
891 | * Note about locks: | |
892 | * | |
893 | * The driver keeps track of which user has what locks on which card. It | |
894 | * supports stacking, like the kernel one. This complexifies the implementation | |
895 | * a bit, but makes the arbiter more tolerant to userspace problems and able | |
896 | * to properly cleanup in all cases when a process dies. | |
897 | * Currently, a max of 16 cards simultaneously can have locks issued from | |
898 | * userspace for a given user (file descriptor instance) of the arbiter. | |
899 | * | |
900 | * If the device is hot-unplugged, there is a hook inside the module to notify | |
901 | * they being added/removed in the system and automatically added/removed in | |
902 | * the arbiter. | |
903 | */ | |
904 | ||
36028f33 | 905 | #define MAX_USER_CARDS CONFIG_VGA_ARB_MAX_GPUS |
deb2d2ec BH |
906 | #define PCI_INVALID_CARD ((struct pci_dev *)-1UL) |
907 | ||
908 | /* | |
909 | * Each user has an array of these, tracking which cards have locks | |
910 | */ | |
911 | struct vga_arb_user_card { | |
912 | struct pci_dev *pdev; | |
913 | unsigned int mem_cnt; | |
914 | unsigned int io_cnt; | |
915 | }; | |
916 | ||
917 | struct vga_arb_private { | |
918 | struct list_head list; | |
919 | struct pci_dev *target; | |
920 | struct vga_arb_user_card cards[MAX_USER_CARDS]; | |
921 | spinlock_t lock; | |
922 | }; | |
923 | ||
924 | static LIST_HEAD(vga_user_list); | |
925 | static DEFINE_SPINLOCK(vga_user_lock); | |
926 | ||
927 | ||
928 | /* | |
929 | * This function gets a string in the format: "PCI:domain:bus:dev.fn" and | |
930 | * returns the respective values. If the string is not in this format, | |
931 | * it returns 0. | |
932 | */ | |
933 | static int vga_pci_str_to_vars(char *buf, int count, unsigned int *domain, | |
934 | unsigned int *bus, unsigned int *devfn) | |
935 | { | |
936 | int n; | |
937 | unsigned int slot, func; | |
938 | ||
939 | ||
940 | n = sscanf(buf, "PCI:%x:%x:%x.%x", domain, bus, &slot, &func); | |
941 | if (n != 4) | |
942 | return 0; | |
943 | ||
944 | *devfn = PCI_DEVFN(slot, func); | |
945 | ||
946 | return 1; | |
947 | } | |
948 | ||
5d90ccf9 | 949 | static ssize_t vga_arb_read(struct file *file, char __user *buf, |
deb2d2ec BH |
950 | size_t count, loff_t *ppos) |
951 | { | |
952 | struct vga_arb_private *priv = file->private_data; | |
953 | struct vga_device *vgadev; | |
954 | struct pci_dev *pdev; | |
955 | unsigned long flags; | |
956 | size_t len; | |
957 | int rc; | |
958 | char *lbuf; | |
959 | ||
960 | lbuf = kmalloc(1024, GFP_KERNEL); | |
961 | if (lbuf == NULL) | |
962 | return -ENOMEM; | |
963 | ||
964 | /* Shields against vga_arb_device_card_gone (pci_dev going | |
965 | * away), and allows access to vga list | |
966 | */ | |
967 | spin_lock_irqsave(&vga_lock, flags); | |
968 | ||
25985edc | 969 | /* If we are targeting the default, use it */ |
deb2d2ec BH |
970 | pdev = priv->target; |
971 | if (pdev == NULL || pdev == PCI_INVALID_CARD) { | |
972 | spin_unlock_irqrestore(&vga_lock, flags); | |
973 | len = sprintf(lbuf, "invalid"); | |
974 | goto done; | |
975 | } | |
976 | ||
977 | /* Find card vgadev structure */ | |
978 | vgadev = vgadev_find(pdev); | |
979 | if (vgadev == NULL) { | |
980 | /* Wow, it's not in the list, that shouldn't happen, | |
981 | * let's fix us up and return invalid card | |
982 | */ | |
983 | if (pdev == priv->target) | |
984 | vga_arb_device_card_gone(pdev); | |
985 | spin_unlock_irqrestore(&vga_lock, flags); | |
986 | len = sprintf(lbuf, "invalid"); | |
987 | goto done; | |
988 | } | |
989 | ||
990 | /* Fill the buffer with infos */ | |
991 | len = snprintf(lbuf, 1024, | |
992 | "count:%d,PCI:%s,decodes=%s,owns=%s,locks=%s(%d:%d)\n", | |
993 | vga_decode_count, pci_name(pdev), | |
994 | vga_iostate_to_str(vgadev->decodes), | |
995 | vga_iostate_to_str(vgadev->owns), | |
996 | vga_iostate_to_str(vgadev->locks), | |
997 | vgadev->io_lock_cnt, vgadev->mem_lock_cnt); | |
998 | ||
999 | spin_unlock_irqrestore(&vga_lock, flags); | |
1000 | done: | |
1001 | ||
1002 | /* Copy that to user */ | |
1003 | if (len > count) | |
1004 | len = count; | |
1005 | rc = copy_to_user(buf, lbuf, len); | |
1006 | kfree(lbuf); | |
1007 | if (rc) | |
1008 | return -EFAULT; | |
1009 | return len; | |
1010 | } | |
1011 | ||
1012 | /* | |
1013 | * TODO: To avoid parsing inside kernel and to improve the speed we may | |
1014 | * consider use ioctl here | |
1015 | */ | |
5d90ccf9 | 1016 | static ssize_t vga_arb_write(struct file *file, const char __user *buf, |
deb2d2ec BH |
1017 | size_t count, loff_t *ppos) |
1018 | { | |
1019 | struct vga_arb_private *priv = file->private_data; | |
1020 | struct vga_arb_user_card *uc = NULL; | |
1021 | struct pci_dev *pdev; | |
1022 | ||
1023 | unsigned int io_state; | |
1024 | ||
49521b13 | 1025 | char kbuf[64], *curr_pos; |
deb2d2ec BH |
1026 | size_t remaining = count; |
1027 | ||
1028 | int ret_val; | |
1029 | int i; | |
1030 | ||
49521b13 DV |
1031 | if (count >= sizeof(kbuf)) |
1032 | return -EINVAL; | |
1033 | if (copy_from_user(kbuf, buf, count)) | |
deb2d2ec | 1034 | return -EFAULT; |
deb2d2ec BH |
1035 | curr_pos = kbuf; |
1036 | kbuf[count] = '\0'; /* Just to make sure... */ | |
1037 | ||
1038 | if (strncmp(curr_pos, "lock ", 5) == 0) { | |
1039 | curr_pos += 5; | |
1040 | remaining -= 5; | |
1041 | ||
2d6e9b91 | 1042 | pr_debug("client 0x%p called 'lock'\n", priv); |
deb2d2ec BH |
1043 | |
1044 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1045 | ret_val = -EPROTO; | |
1046 | goto done; | |
1047 | } | |
1048 | if (io_state == VGA_RSRC_NONE) { | |
1049 | ret_val = -EPROTO; | |
1050 | goto done; | |
1051 | } | |
1052 | ||
1053 | pdev = priv->target; | |
1054 | if (priv->target == NULL) { | |
1055 | ret_val = -ENODEV; | |
1056 | goto done; | |
1057 | } | |
1058 | ||
1059 | vga_get_uninterruptible(pdev, io_state); | |
1060 | ||
1061 | /* Update the client's locks lists... */ | |
1062 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1063 | if (priv->cards[i].pdev == pdev) { | |
1064 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1065 | priv->cards[i].io_cnt++; | |
1066 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1067 | priv->cards[i].mem_cnt++; | |
1068 | break; | |
1069 | } | |
1070 | } | |
1071 | ||
1072 | ret_val = count; | |
1073 | goto done; | |
1074 | } else if (strncmp(curr_pos, "unlock ", 7) == 0) { | |
1075 | curr_pos += 7; | |
1076 | remaining -= 7; | |
1077 | ||
2d6e9b91 | 1078 | pr_debug("client 0x%p called 'unlock'\n", priv); |
deb2d2ec BH |
1079 | |
1080 | if (strncmp(curr_pos, "all", 3) == 0) | |
1081 | io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
1082 | else { | |
1083 | if (!vga_str_to_iostate | |
1084 | (curr_pos, remaining, &io_state)) { | |
1085 | ret_val = -EPROTO; | |
1086 | goto done; | |
1087 | } | |
1088 | /* TODO: Add this? | |
1089 | if (io_state == VGA_RSRC_NONE) { | |
1090 | ret_val = -EPROTO; | |
1091 | goto done; | |
1092 | } | |
1093 | */ | |
1094 | } | |
1095 | ||
1096 | pdev = priv->target; | |
1097 | if (priv->target == NULL) { | |
1098 | ret_val = -ENODEV; | |
1099 | goto done; | |
1100 | } | |
1101 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1102 | if (priv->cards[i].pdev == pdev) | |
1103 | uc = &priv->cards[i]; | |
1104 | } | |
1105 | ||
c916874d JL |
1106 | if (!uc) { |
1107 | ret_val = -EINVAL; | |
1108 | goto done; | |
1109 | } | |
deb2d2ec | 1110 | |
c916874d JL |
1111 | if (io_state & VGA_RSRC_LEGACY_IO && uc->io_cnt == 0) { |
1112 | ret_val = -EINVAL; | |
1113 | goto done; | |
1114 | } | |
deb2d2ec | 1115 | |
c916874d JL |
1116 | if (io_state & VGA_RSRC_LEGACY_MEM && uc->mem_cnt == 0) { |
1117 | ret_val = -EINVAL; | |
1118 | goto done; | |
1119 | } | |
deb2d2ec BH |
1120 | |
1121 | vga_put(pdev, io_state); | |
1122 | ||
1123 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1124 | uc->io_cnt--; | |
1125 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1126 | uc->mem_cnt--; | |
1127 | ||
1128 | ret_val = count; | |
1129 | goto done; | |
1130 | } else if (strncmp(curr_pos, "trylock ", 8) == 0) { | |
1131 | curr_pos += 8; | |
1132 | remaining -= 8; | |
1133 | ||
2d6e9b91 | 1134 | pr_debug("client 0x%p called 'trylock'\n", priv); |
deb2d2ec BH |
1135 | |
1136 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1137 | ret_val = -EPROTO; | |
1138 | goto done; | |
1139 | } | |
1140 | /* TODO: Add this? | |
1141 | if (io_state == VGA_RSRC_NONE) { | |
1142 | ret_val = -EPROTO; | |
1143 | goto done; | |
1144 | } | |
1145 | */ | |
1146 | ||
1147 | pdev = priv->target; | |
1148 | if (priv->target == NULL) { | |
1149 | ret_val = -ENODEV; | |
1150 | goto done; | |
1151 | } | |
1152 | ||
1153 | if (vga_tryget(pdev, io_state)) { | |
1154 | /* Update the client's locks lists... */ | |
1155 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1156 | if (priv->cards[i].pdev == pdev) { | |
1157 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1158 | priv->cards[i].io_cnt++; | |
1159 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1160 | priv->cards[i].mem_cnt++; | |
1161 | break; | |
1162 | } | |
1163 | } | |
1164 | ret_val = count; | |
1165 | goto done; | |
1166 | } else { | |
1167 | ret_val = -EBUSY; | |
1168 | goto done; | |
1169 | } | |
1170 | ||
1171 | } else if (strncmp(curr_pos, "target ", 7) == 0) { | |
1172 | unsigned int domain, bus, devfn; | |
1173 | struct vga_device *vgadev; | |
1174 | ||
1175 | curr_pos += 7; | |
1176 | remaining -= 7; | |
2d6e9b91 | 1177 | pr_debug("client 0x%p called 'target'\n", priv); |
deb2d2ec | 1178 | /* if target is default */ |
2cc9116c | 1179 | if (!strncmp(curr_pos, "default", 7)) |
deb2d2ec BH |
1180 | pdev = pci_dev_get(vga_default_device()); |
1181 | else { | |
1182 | if (!vga_pci_str_to_vars(curr_pos, remaining, | |
1183 | &domain, &bus, &devfn)) { | |
1184 | ret_val = -EPROTO; | |
1185 | goto done; | |
1186 | } | |
8b7e2e86 | 1187 | pr_debug("%s ==> %x:%x:%x.%x\n", curr_pos, |
773a38db MT |
1188 | domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn)); |
1189 | ||
f85567c8 | 1190 | pdev = pci_get_domain_bus_and_slot(domain, bus, devfn); |
8b7e2e86 | 1191 | pr_debug("pdev %p\n", pdev); |
deb2d2ec | 1192 | if (!pdev) { |
8b7e2e86 | 1193 | pr_err("invalid PCI address %x:%x:%x\n", |
f85567c8 | 1194 | domain, bus, devfn); |
deb2d2ec BH |
1195 | ret_val = -ENODEV; |
1196 | goto done; | |
1197 | } | |
1198 | } | |
1199 | ||
1200 | vgadev = vgadev_find(pdev); | |
8b7e2e86 | 1201 | pr_debug("vgadev %p\n", vgadev); |
deb2d2ec | 1202 | if (vgadev == NULL) { |
eb6944f2 | 1203 | if (pdev) { |
8b7e2e86 | 1204 | pr_err("this pci device is not a vga device\n"); |
eb6944f2 TR |
1205 | pci_dev_put(pdev); |
1206 | } | |
1207 | ||
deb2d2ec BH |
1208 | ret_val = -ENODEV; |
1209 | goto done; | |
1210 | } | |
1211 | ||
1212 | priv->target = pdev; | |
1213 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1214 | if (priv->cards[i].pdev == pdev) | |
1215 | break; | |
1216 | if (priv->cards[i].pdev == NULL) { | |
1217 | priv->cards[i].pdev = pdev; | |
1218 | priv->cards[i].io_cnt = 0; | |
1219 | priv->cards[i].mem_cnt = 0; | |
1220 | break; | |
1221 | } | |
1222 | } | |
1223 | if (i == MAX_USER_CARDS) { | |
8b7e2e86 | 1224 | pr_err("maximum user cards (%d) number reached!\n", |
773a38db | 1225 | MAX_USER_CARDS); |
deb2d2ec BH |
1226 | pci_dev_put(pdev); |
1227 | /* XXX: which value to return? */ | |
1228 | ret_val = -ENOMEM; | |
1229 | goto done; | |
1230 | } | |
1231 | ||
1232 | ret_val = count; | |
1233 | pci_dev_put(pdev); | |
1234 | goto done; | |
1235 | ||
1236 | ||
1237 | } else if (strncmp(curr_pos, "decodes ", 8) == 0) { | |
1238 | curr_pos += 8; | |
1239 | remaining -= 8; | |
8b7e2e86 | 1240 | pr_debug("client 0x%p called 'decodes'\n", priv); |
deb2d2ec BH |
1241 | |
1242 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1243 | ret_val = -EPROTO; | |
1244 | goto done; | |
1245 | } | |
1246 | pdev = priv->target; | |
1247 | if (priv->target == NULL) { | |
1248 | ret_val = -ENODEV; | |
1249 | goto done; | |
1250 | } | |
1251 | ||
1252 | __vga_set_legacy_decoding(pdev, io_state, true); | |
1253 | ret_val = count; | |
1254 | goto done; | |
1255 | } | |
1256 | /* If we got here, the message written is not part of the protocol! */ | |
deb2d2ec BH |
1257 | return -EPROTO; |
1258 | ||
1259 | done: | |
deb2d2ec BH |
1260 | return ret_val; |
1261 | } | |
1262 | ||
5d90ccf9 | 1263 | static unsigned int vga_arb_fpoll(struct file *file, poll_table *wait) |
deb2d2ec | 1264 | { |
2d6e9b91 | 1265 | pr_debug("%s\n", __func__); |
deb2d2ec | 1266 | |
deb2d2ec BH |
1267 | poll_wait(file, &vga_wait_queue, wait); |
1268 | return POLLIN; | |
1269 | } | |
1270 | ||
1271 | static int vga_arb_open(struct inode *inode, struct file *file) | |
1272 | { | |
1273 | struct vga_arb_private *priv; | |
1274 | unsigned long flags; | |
1275 | ||
2d6e9b91 | 1276 | pr_debug("%s\n", __func__); |
deb2d2ec | 1277 | |
f35119d6 | 1278 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); |
deb2d2ec BH |
1279 | if (priv == NULL) |
1280 | return -ENOMEM; | |
deb2d2ec BH |
1281 | spin_lock_init(&priv->lock); |
1282 | file->private_data = priv; | |
1283 | ||
1284 | spin_lock_irqsave(&vga_user_lock, flags); | |
1285 | list_add(&priv->list, &vga_user_list); | |
1286 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1287 | ||
1288 | /* Set the client' lists of locks */ | |
1289 | priv->target = vga_default_device(); /* Maybe this is still null! */ | |
1290 | priv->cards[0].pdev = priv->target; | |
1291 | priv->cards[0].io_cnt = 0; | |
1292 | priv->cards[0].mem_cnt = 0; | |
1293 | ||
1294 | ||
1295 | return 0; | |
1296 | } | |
1297 | ||
1298 | static int vga_arb_release(struct inode *inode, struct file *file) | |
1299 | { | |
1300 | struct vga_arb_private *priv = file->private_data; | |
1301 | struct vga_arb_user_card *uc; | |
1302 | unsigned long flags; | |
1303 | int i; | |
1304 | ||
2d6e9b91 | 1305 | pr_debug("%s\n", __func__); |
deb2d2ec | 1306 | |
deb2d2ec BH |
1307 | spin_lock_irqsave(&vga_user_lock, flags); |
1308 | list_del(&priv->list); | |
1309 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1310 | uc = &priv->cards[i]; | |
1311 | if (uc->pdev == NULL) | |
1312 | continue; | |
2d6e9b91 | 1313 | pr_debug("uc->io_cnt == %d, uc->mem_cnt == %d\n", |
deb2d2ec BH |
1314 | uc->io_cnt, uc->mem_cnt); |
1315 | while (uc->io_cnt--) | |
1316 | vga_put(uc->pdev, VGA_RSRC_LEGACY_IO); | |
1317 | while (uc->mem_cnt--) | |
1318 | vga_put(uc->pdev, VGA_RSRC_LEGACY_MEM); | |
1319 | } | |
1320 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1321 | ||
1322 | kfree(priv); | |
1323 | ||
1324 | return 0; | |
1325 | } | |
1326 | ||
1327 | static void vga_arb_device_card_gone(struct pci_dev *pdev) | |
1328 | { | |
1329 | } | |
1330 | ||
1331 | /* | |
1332 | * callback any registered clients to let them know we have a | |
1333 | * change in VGA cards | |
1334 | */ | |
1335 | static void vga_arbiter_notify_clients(void) | |
1336 | { | |
1337 | struct vga_device *vgadev; | |
1338 | unsigned long flags; | |
1339 | uint32_t new_decodes; | |
1340 | bool new_state; | |
1341 | ||
1342 | if (!vga_arbiter_used) | |
1343 | return; | |
1344 | ||
1345 | spin_lock_irqsave(&vga_lock, flags); | |
1346 | list_for_each_entry(vgadev, &vga_list, list) { | |
1347 | if (vga_count > 1) | |
1348 | new_state = false; | |
1349 | else | |
1350 | new_state = true; | |
1351 | if (vgadev->set_vga_decode) { | |
5d90ccf9 TR |
1352 | new_decodes = vgadev->set_vga_decode(vgadev->cookie, |
1353 | new_state); | |
deb2d2ec BH |
1354 | vga_update_device_decodes(vgadev, new_decodes); |
1355 | } | |
1356 | } | |
1357 | spin_unlock_irqrestore(&vga_lock, flags); | |
1358 | } | |
1359 | ||
1360 | static int pci_notify(struct notifier_block *nb, unsigned long action, | |
1361 | void *data) | |
1362 | { | |
1363 | struct device *dev = data; | |
1364 | struct pci_dev *pdev = to_pci_dev(dev); | |
1365 | bool notify = false; | |
1366 | ||
2d6e9b91 | 1367 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1368 | |
1369 | /* For now we're only intereted in devices added and removed. I didn't | |
1370 | * test this thing here, so someone needs to double check for the | |
1371 | * cases of hotplugable vga cards. */ | |
1372 | if (action == BUS_NOTIFY_ADD_DEVICE) | |
1373 | notify = vga_arbiter_add_pci_device(pdev); | |
1374 | else if (action == BUS_NOTIFY_DEL_DEVICE) | |
1375 | notify = vga_arbiter_del_pci_device(pdev); | |
1376 | ||
1377 | if (notify) | |
1378 | vga_arbiter_notify_clients(); | |
1379 | return 0; | |
1380 | } | |
1381 | ||
1382 | static struct notifier_block pci_notifier = { | |
1383 | .notifier_call = pci_notify, | |
1384 | }; | |
1385 | ||
1386 | static const struct file_operations vga_arb_device_fops = { | |
1387 | .read = vga_arb_read, | |
1388 | .write = vga_arb_write, | |
1389 | .poll = vga_arb_fpoll, | |
1390 | .open = vga_arb_open, | |
1391 | .release = vga_arb_release, | |
6038f373 | 1392 | .llseek = noop_llseek, |
deb2d2ec BH |
1393 | }; |
1394 | ||
1395 | static struct miscdevice vga_arb_device = { | |
1396 | MISC_DYNAMIC_MINOR, "vga_arbiter", &vga_arb_device_fops | |
1397 | }; | |
1398 | ||
1399 | static int __init vga_arb_device_init(void) | |
1400 | { | |
1401 | int rc; | |
1402 | struct pci_dev *pdev; | |
3448a19d | 1403 | struct vga_device *vgadev; |
deb2d2ec BH |
1404 | |
1405 | rc = misc_register(&vga_arb_device); | |
1406 | if (rc < 0) | |
8b7e2e86 | 1407 | pr_err("error %d registering device\n", rc); |
deb2d2ec BH |
1408 | |
1409 | bus_register_notifier(&pci_bus_type, &pci_notifier); | |
1410 | ||
1411 | /* We add all pci devices satisfying vga class in the arbiter by | |
1412 | * default */ | |
1413 | pdev = NULL; | |
1414 | while ((pdev = | |
1415 | pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, | |
1416 | PCI_ANY_ID, pdev)) != NULL) | |
1417 | vga_arbiter_add_pci_device(pdev); | |
1418 | ||
8b7e2e86 | 1419 | pr_info("loaded\n"); |
3448a19d DA |
1420 | |
1421 | list_for_each_entry(vgadev, &vga_list, list) { | |
86fd887b | 1422 | #if defined(CONFIG_X86) || defined(CONFIG_IA64) |
5d90ccf9 TR |
1423 | /* |
1424 | * Override vga_arbiter_add_pci_device()'s I/O based detection | |
1425 | * as it may take the wrong device (e.g. on Apple system under | |
1426 | * EFI). | |
86fd887b | 1427 | * |
5d90ccf9 TR |
1428 | * Select the device owning the boot framebuffer if there is |
1429 | * one. | |
86fd887b | 1430 | */ |
5d90ccf9 TR |
1431 | resource_size_t start, end, limit; |
1432 | unsigned long flags; | |
86fd887b BP |
1433 | int i; |
1434 | ||
5d90ccf9 TR |
1435 | limit = screen_info.lfb_base + screen_info.lfb_size; |
1436 | ||
86fd887b BP |
1437 | /* Does firmware framebuffer belong to us? */ |
1438 | for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) { | |
5d90ccf9 TR |
1439 | flags = pci_resource_flags(vgadev->pdev, i); |
1440 | ||
1441 | if ((flags & IORESOURCE_MEM) == 0) | |
86fd887b BP |
1442 | continue; |
1443 | ||
1444 | start = pci_resource_start(vgadev->pdev, i); | |
1445 | end = pci_resource_end(vgadev->pdev, i); | |
1446 | ||
1447 | if (!start || !end) | |
1448 | continue; | |
1449 | ||
5d90ccf9 | 1450 | if (screen_info.lfb_base < start || limit >= end) |
86fd887b | 1451 | continue; |
5d90ccf9 | 1452 | |
86fd887b | 1453 | if (!vga_default_device()) |
8b7e2e86 | 1454 | pr_info("setting as boot device: PCI:%s\n", |
86fd887b BP |
1455 | pci_name(vgadev->pdev)); |
1456 | else if (vgadev->pdev != vga_default_device()) | |
8b7e2e86 | 1457 | pr_info("overriding boot device: PCI:%s\n", |
86fd887b BP |
1458 | pci_name(vgadev->pdev)); |
1459 | vga_set_default_device(vgadev->pdev); | |
1460 | } | |
1461 | #endif | |
3448a19d | 1462 | if (vgadev->bridge_has_one_vga) |
5d90ccf9 TR |
1463 | pr_info("bridge control possible %s\n", |
1464 | pci_name(vgadev->pdev)); | |
3448a19d | 1465 | else |
5d90ccf9 TR |
1466 | pr_info("no bridge control possible %s\n", |
1467 | pci_name(vgadev->pdev)); | |
3448a19d | 1468 | } |
deb2d2ec BH |
1469 | return rc; |
1470 | } | |
1471 | subsys_initcall(vga_arb_device_init); |