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 | ||
8b7e2e86 TR |
32 | #define pr_fmt(fmt) "vgaarb: " fmt |
33 | ||
a75d68f6 BH |
34 | #define vgaarb_dbg(dev, fmt, arg...) dev_dbg(dev, "vgaarb: " fmt, ##arg) |
35 | #define vgaarb_info(dev, fmt, arg...) dev_info(dev, "vgaarb: " fmt, ##arg) | |
36 | #define vgaarb_err(dev, fmt, arg...) dev_err(dev, "vgaarb: " fmt, ##arg) | |
37 | ||
deb2d2ec BH |
38 | #include <linux/module.h> |
39 | #include <linux/kernel.h> | |
40 | #include <linux/pci.h> | |
41 | #include <linux/errno.h> | |
42 | #include <linux/init.h> | |
43 | #include <linux/list.h> | |
44 | #include <linux/sched.h> | |
45 | #include <linux/wait.h> | |
46 | #include <linux/spinlock.h> | |
47 | #include <linux/poll.h> | |
48 | #include <linux/miscdevice.h> | |
5a0e3ad6 | 49 | #include <linux/slab.h> |
86fd887b | 50 | #include <linux/screen_info.h> |
deb2d2ec BH |
51 | |
52 | #include <linux/uaccess.h> | |
53 | ||
54 | #include <linux/vgaarb.h> | |
55 | ||
56 | static void vga_arbiter_notify_clients(void); | |
57 | /* | |
58 | * We keep a list of all vga devices in the system to speed | |
59 | * up the various operations of the arbiter | |
60 | */ | |
61 | struct vga_device { | |
62 | struct list_head list; | |
63 | struct pci_dev *pdev; | |
64 | unsigned int decodes; /* what does it decodes */ | |
65 | unsigned int owns; /* what does it owns */ | |
66 | unsigned int locks; /* what does it locks */ | |
67 | unsigned int io_lock_cnt; /* legacy IO lock count */ | |
68 | unsigned int mem_lock_cnt; /* legacy MEM lock count */ | |
69 | unsigned int io_norm_cnt; /* normal IO count */ | |
70 | unsigned int mem_norm_cnt; /* normal MEM count */ | |
3448a19d | 71 | bool bridge_has_one_vga; |
deb2d2ec BH |
72 | /* allow IRQ enable/disable hook */ |
73 | void *cookie; | |
74 | void (*irq_set_state)(void *cookie, bool enable); | |
75 | unsigned int (*set_vga_decode)(void *cookie, bool decode); | |
76 | }; | |
77 | ||
78 | static LIST_HEAD(vga_list); | |
79 | static int vga_count, vga_decode_count; | |
80 | static bool vga_arbiter_used; | |
81 | static DEFINE_SPINLOCK(vga_lock); | |
82 | static DECLARE_WAIT_QUEUE_HEAD(vga_wait_queue); | |
83 | ||
84 | ||
85 | static const char *vga_iostate_to_str(unsigned int iostate) | |
86 | { | |
87 | /* Ignore VGA_RSRC_IO and VGA_RSRC_MEM */ | |
88 | iostate &= VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
89 | switch (iostate) { | |
90 | case VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM: | |
91 | return "io+mem"; | |
92 | case VGA_RSRC_LEGACY_IO: | |
93 | return "io"; | |
94 | case VGA_RSRC_LEGACY_MEM: | |
95 | return "mem"; | |
96 | } | |
97 | return "none"; | |
98 | } | |
99 | ||
100 | static int vga_str_to_iostate(char *buf, int str_size, int *io_state) | |
101 | { | |
102 | /* we could in theory hand out locks on IO and mem | |
103 | * separately to userspace but it can cause deadlocks */ | |
104 | if (strncmp(buf, "none", 4) == 0) { | |
105 | *io_state = VGA_RSRC_NONE; | |
106 | return 1; | |
107 | } | |
108 | ||
109 | /* XXX We're not chekcing the str_size! */ | |
110 | if (strncmp(buf, "io+mem", 6) == 0) | |
111 | goto both; | |
112 | else if (strncmp(buf, "io", 2) == 0) | |
113 | goto both; | |
114 | else if (strncmp(buf, "mem", 3) == 0) | |
115 | goto both; | |
116 | return 0; | |
117 | both: | |
118 | *io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
119 | return 1; | |
120 | } | |
121 | ||
deb2d2ec BH |
122 | /* this is only used a cookie - it should not be dereferenced */ |
123 | static struct pci_dev *vga_default; | |
deb2d2ec BH |
124 | |
125 | static void vga_arb_device_card_gone(struct pci_dev *pdev); | |
126 | ||
127 | /* Find somebody in our list */ | |
128 | static struct vga_device *vgadev_find(struct pci_dev *pdev) | |
129 | { | |
130 | struct vga_device *vgadev; | |
131 | ||
132 | list_for_each_entry(vgadev, &vga_list, list) | |
133 | if (pdev == vgadev->pdev) | |
134 | return vgadev; | |
135 | return NULL; | |
136 | } | |
137 | ||
b754b35b DV |
138 | /** |
139 | * vga_default_device - return the default VGA device, for vgacon | |
140 | * | |
141 | * This can be defined by the platform. The default implementation | |
142 | * is rather dumb and will probably only work properly on single | |
143 | * vga card setups and/or x86 platforms. | |
144 | * | |
145 | * If your VGA default device is not PCI, you'll have to return | |
146 | * NULL here. In this case, I assume it will not conflict with | |
147 | * any PCI card. If this is not true, I'll have to define two archs | |
148 | * hooks for enabling/disabling the VGA default device if that is | |
149 | * possible. This may be a problem with real _ISA_ VGA cards, in | |
150 | * addition to a PCI one. I don't know at this point how to deal | |
151 | * with that card. Can theirs IOs be disabled at all ? If not, then | |
152 | * I suppose it's a matter of having the proper arch hook telling | |
153 | * us about it, so we basically never allow anybody to succeed a | |
154 | * vga_get()... | |
155 | */ | |
deb2d2ec BH |
156 | struct pci_dev *vga_default_device(void) |
157 | { | |
158 | return vga_default; | |
159 | } | |
1b23170a MG |
160 | EXPORT_SYMBOL_GPL(vga_default_device); |
161 | ||
1a39b310 MG |
162 | void vga_set_default_device(struct pci_dev *pdev) |
163 | { | |
84544a1d YL |
164 | if (vga_default == pdev) |
165 | return; | |
166 | ||
167 | pci_dev_put(vga_default); | |
168 | vga_default = pci_dev_get(pdev); | |
1a39b310 | 169 | } |
deb2d2ec BH |
170 | |
171 | static inline void vga_irq_set_state(struct vga_device *vgadev, bool state) | |
172 | { | |
173 | if (vgadev->irq_set_state) | |
174 | vgadev->irq_set_state(vgadev->cookie, state); | |
175 | } | |
176 | ||
177 | ||
178 | /* If we don't ever use VGA arb we should avoid | |
179 | turning off anything anywhere due to old X servers getting | |
180 | confused about the boot device not being VGA */ | |
181 | static void vga_check_first_use(void) | |
182 | { | |
183 | /* we should inform all GPUs in the system that | |
25985edc | 184 | * VGA arb has occurred and to try and disable resources |
deb2d2ec BH |
185 | * if they can */ |
186 | if (!vga_arbiter_used) { | |
187 | vga_arbiter_used = true; | |
188 | vga_arbiter_notify_clients(); | |
189 | } | |
190 | } | |
191 | ||
192 | static struct vga_device *__vga_tryget(struct vga_device *vgadev, | |
193 | unsigned int rsrc) | |
194 | { | |
a75d68f6 | 195 | struct device *dev = &vgadev->pdev->dev; |
deb2d2ec BH |
196 | unsigned int wants, legacy_wants, match; |
197 | struct vga_device *conflict; | |
198 | unsigned int pci_bits; | |
3448a19d DA |
199 | u32 flags = 0; |
200 | ||
deb2d2ec BH |
201 | /* Account for "normal" resources to lock. If we decode the legacy, |
202 | * counterpart, we need to request it as well | |
203 | */ | |
204 | if ((rsrc & VGA_RSRC_NORMAL_IO) && | |
205 | (vgadev->decodes & VGA_RSRC_LEGACY_IO)) | |
206 | rsrc |= VGA_RSRC_LEGACY_IO; | |
207 | if ((rsrc & VGA_RSRC_NORMAL_MEM) && | |
208 | (vgadev->decodes & VGA_RSRC_LEGACY_MEM)) | |
209 | rsrc |= VGA_RSRC_LEGACY_MEM; | |
210 | ||
a75d68f6 BH |
211 | vgaarb_dbg(dev, "%s: %d\n", __func__, rsrc); |
212 | vgaarb_dbg(dev, "%s: owns: %d\n", __func__, vgadev->owns); | |
deb2d2ec BH |
213 | |
214 | /* Check what resources we need to acquire */ | |
215 | wants = rsrc & ~vgadev->owns; | |
216 | ||
217 | /* We already own everything, just mark locked & bye bye */ | |
218 | if (wants == 0) | |
219 | goto lock_them; | |
220 | ||
221 | /* We don't need to request a legacy resource, we just enable | |
222 | * appropriate decoding and go | |
223 | */ | |
224 | legacy_wants = wants & VGA_RSRC_LEGACY_MASK; | |
225 | if (legacy_wants == 0) | |
226 | goto enable_them; | |
227 | ||
228 | /* Ok, we don't, let's find out how we need to kick off */ | |
229 | list_for_each_entry(conflict, &vga_list, list) { | |
230 | unsigned int lwants = legacy_wants; | |
231 | unsigned int change_bridge = 0; | |
232 | ||
233 | /* Don't conflict with myself */ | |
234 | if (vgadev == conflict) | |
235 | continue; | |
236 | ||
237 | /* Check if the architecture allows a conflict between those | |
238 | * 2 devices or if they are on separate domains | |
239 | */ | |
240 | if (!vga_conflicts(vgadev->pdev, conflict->pdev)) | |
241 | continue; | |
242 | ||
243 | /* We have a possible conflict. before we go further, we must | |
244 | * check if we sit on the same bus as the conflicting device. | |
245 | * if we don't, then we must tie both IO and MEM resources | |
246 | * together since there is only a single bit controlling | |
247 | * VGA forwarding on P2P bridges | |
248 | */ | |
249 | if (vgadev->pdev->bus != conflict->pdev->bus) { | |
250 | change_bridge = 1; | |
251 | lwants = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
252 | } | |
253 | ||
254 | /* Check if the guy has a lock on the resource. If he does, | |
255 | * return the conflicting entry | |
256 | */ | |
257 | if (conflict->locks & lwants) | |
258 | return conflict; | |
259 | ||
4e4e7dc5 AW |
260 | /* Ok, now check if it owns the resource we want. We can |
261 | * lock resources that are not decoded, therefore a device | |
262 | * can own resources it doesn't decode. | |
deb2d2ec | 263 | */ |
deb2d2ec BH |
264 | match = lwants & conflict->owns; |
265 | if (!match) | |
266 | continue; | |
267 | ||
268 | /* looks like he doesn't have a lock, we can steal | |
269 | * them from him | |
270 | */ | |
deb2d2ec | 271 | |
3448a19d | 272 | flags = 0; |
deb2d2ec | 273 | pci_bits = 0; |
deb2d2ec | 274 | |
4e4e7dc5 AW |
275 | /* If we can't control legacy resources via the bridge, we |
276 | * also need to disable normal decoding. | |
277 | */ | |
3448a19d | 278 | if (!conflict->bridge_has_one_vga) { |
4e4e7dc5 | 279 | if ((match & conflict->decodes) & VGA_RSRC_LEGACY_MEM) |
3448a19d | 280 | pci_bits |= PCI_COMMAND_MEMORY; |
4e4e7dc5 | 281 | if ((match & conflict->decodes) & VGA_RSRC_LEGACY_IO) |
3448a19d | 282 | pci_bits |= PCI_COMMAND_IO; |
4e4e7dc5 AW |
283 | |
284 | if (pci_bits) { | |
285 | vga_irq_set_state(conflict, false); | |
286 | flags |= PCI_VGA_STATE_CHANGE_DECODES; | |
287 | } | |
3448a19d DA |
288 | } |
289 | ||
290 | if (change_bridge) | |
291 | flags |= PCI_VGA_STATE_CHANGE_BRIDGE; | |
292 | ||
293 | pci_set_vga_state(conflict->pdev, false, pci_bits, flags); | |
f22d776f | 294 | conflict->owns &= ~match; |
4e4e7dc5 AW |
295 | |
296 | /* If we disabled normal decoding, reflect it in owns */ | |
297 | if (pci_bits & PCI_COMMAND_MEMORY) | |
deb2d2ec | 298 | conflict->owns &= ~VGA_RSRC_NORMAL_MEM; |
4e4e7dc5 | 299 | if (pci_bits & PCI_COMMAND_IO) |
deb2d2ec BH |
300 | conflict->owns &= ~VGA_RSRC_NORMAL_IO; |
301 | } | |
302 | ||
303 | enable_them: | |
304 | /* ok dude, we got it, everybody conflicting has been disabled, let's | |
4e4e7dc5 AW |
305 | * enable us. Mark any bits in "owns" regardless of whether we |
306 | * decoded them. We can lock resources we don't decode, therefore | |
307 | * we must track them via "owns". | |
deb2d2ec | 308 | */ |
3448a19d | 309 | flags = 0; |
deb2d2ec | 310 | pci_bits = 0; |
deb2d2ec | 311 | |
3448a19d DA |
312 | if (!vgadev->bridge_has_one_vga) { |
313 | flags |= PCI_VGA_STATE_CHANGE_DECODES; | |
314 | if (wants & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) | |
315 | pci_bits |= PCI_COMMAND_MEMORY; | |
316 | if (wants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) | |
317 | pci_bits |= PCI_COMMAND_IO; | |
318 | } | |
4e4e7dc5 | 319 | if (wants & VGA_RSRC_LEGACY_MASK) |
3448a19d DA |
320 | flags |= PCI_VGA_STATE_CHANGE_BRIDGE; |
321 | ||
322 | pci_set_vga_state(vgadev->pdev, true, pci_bits, flags); | |
323 | ||
5d90ccf9 | 324 | if (!vgadev->bridge_has_one_vga) |
3448a19d | 325 | vga_irq_set_state(vgadev, true); |
5d90ccf9 | 326 | |
4e4e7dc5 | 327 | vgadev->owns |= wants; |
deb2d2ec BH |
328 | lock_them: |
329 | vgadev->locks |= (rsrc & VGA_RSRC_LEGACY_MASK); | |
330 | if (rsrc & VGA_RSRC_LEGACY_IO) | |
331 | vgadev->io_lock_cnt++; | |
332 | if (rsrc & VGA_RSRC_LEGACY_MEM) | |
333 | vgadev->mem_lock_cnt++; | |
334 | if (rsrc & VGA_RSRC_NORMAL_IO) | |
335 | vgadev->io_norm_cnt++; | |
336 | if (rsrc & VGA_RSRC_NORMAL_MEM) | |
337 | vgadev->mem_norm_cnt++; | |
338 | ||
339 | return NULL; | |
340 | } | |
341 | ||
342 | static void __vga_put(struct vga_device *vgadev, unsigned int rsrc) | |
343 | { | |
a75d68f6 | 344 | struct device *dev = &vgadev->pdev->dev; |
deb2d2ec BH |
345 | unsigned int old_locks = vgadev->locks; |
346 | ||
a75d68f6 | 347 | vgaarb_dbg(dev, "%s\n", __func__); |
deb2d2ec BH |
348 | |
349 | /* Update our counters, and account for equivalent legacy resources | |
350 | * if we decode them | |
351 | */ | |
352 | if ((rsrc & VGA_RSRC_NORMAL_IO) && vgadev->io_norm_cnt > 0) { | |
353 | vgadev->io_norm_cnt--; | |
354 | if (vgadev->decodes & VGA_RSRC_LEGACY_IO) | |
355 | rsrc |= VGA_RSRC_LEGACY_IO; | |
356 | } | |
357 | if ((rsrc & VGA_RSRC_NORMAL_MEM) && vgadev->mem_norm_cnt > 0) { | |
358 | vgadev->mem_norm_cnt--; | |
359 | if (vgadev->decodes & VGA_RSRC_LEGACY_MEM) | |
360 | rsrc |= VGA_RSRC_LEGACY_MEM; | |
361 | } | |
362 | if ((rsrc & VGA_RSRC_LEGACY_IO) && vgadev->io_lock_cnt > 0) | |
363 | vgadev->io_lock_cnt--; | |
364 | if ((rsrc & VGA_RSRC_LEGACY_MEM) && vgadev->mem_lock_cnt > 0) | |
365 | vgadev->mem_lock_cnt--; | |
366 | ||
367 | /* Just clear lock bits, we do lazy operations so we don't really | |
368 | * have to bother about anything else at this point | |
369 | */ | |
370 | if (vgadev->io_lock_cnt == 0) | |
371 | vgadev->locks &= ~VGA_RSRC_LEGACY_IO; | |
372 | if (vgadev->mem_lock_cnt == 0) | |
373 | vgadev->locks &= ~VGA_RSRC_LEGACY_MEM; | |
374 | ||
375 | /* Kick the wait queue in case somebody was waiting if we actually | |
376 | * released something | |
377 | */ | |
378 | if (old_locks != vgadev->locks) | |
379 | wake_up_all(&vga_wait_queue); | |
380 | } | |
381 | ||
b754b35b DV |
382 | /** |
383 | * vga_get - acquire & locks VGA resources | |
384 | * @pdev: pci device of the VGA card or NULL for the system default | |
385 | * @rsrc: bit mask of resources to acquire and lock | |
386 | * @interruptible: blocking should be interruptible by signals ? | |
387 | * | |
388 | * This function acquires VGA resources for the given card and mark those | |
389 | * resources locked. If the resource requested are "normal" (and not legacy) | |
390 | * resources, the arbiter will first check whether the card is doing legacy | |
391 | * decoding for that type of resource. If yes, the lock is "converted" into a | |
392 | * legacy resource lock. | |
393 | * | |
394 | * The arbiter will first look for all VGA cards that might conflict and disable | |
395 | * their IOs and/or Memory access, including VGA forwarding on P2P bridges if | |
396 | * necessary, so that the requested resources can be used. Then, the card is | |
397 | * marked as locking these resources and the IO and/or Memory accesses are | |
398 | * enabled on the card (including VGA forwarding on parent P2P bridges if any). | |
399 | * | |
400 | * This function will block if some conflicting card is already locking one of | |
401 | * the required resources (or any resource on a different bus segment, since P2P | |
402 | * bridges don't differentiate VGA memory and IO afaik). You can indicate | |
403 | * whether this blocking should be interruptible by a signal (for userland | |
404 | * interface) or not. | |
405 | * | |
406 | * Must not be called at interrupt time or in atomic context. If the card | |
407 | * already owns the resources, the function succeeds. Nested calls are | |
408 | * supported (a per-resource counter is maintained) | |
409 | * | |
410 | * On success, release the VGA resource again with vga_put(). | |
411 | * | |
412 | * Returns: | |
413 | * | |
414 | * 0 on success, negative error code on failure. | |
415 | */ | |
deb2d2ec BH |
416 | int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible) |
417 | { | |
418 | struct vga_device *vgadev, *conflict; | |
419 | unsigned long flags; | |
420 | wait_queue_t wait; | |
421 | int rc = 0; | |
422 | ||
423 | vga_check_first_use(); | |
424 | /* The one who calls us should check for this, but lets be sure... */ | |
425 | if (pdev == NULL) | |
426 | pdev = vga_default_device(); | |
427 | if (pdev == NULL) | |
428 | return 0; | |
429 | ||
430 | for (;;) { | |
431 | spin_lock_irqsave(&vga_lock, flags); | |
432 | vgadev = vgadev_find(pdev); | |
433 | if (vgadev == NULL) { | |
434 | spin_unlock_irqrestore(&vga_lock, flags); | |
435 | rc = -ENODEV; | |
436 | break; | |
437 | } | |
438 | conflict = __vga_tryget(vgadev, rsrc); | |
439 | spin_unlock_irqrestore(&vga_lock, flags); | |
440 | if (conflict == NULL) | |
441 | break; | |
442 | ||
443 | ||
444 | /* We have a conflict, we wait until somebody kicks the | |
445 | * work queue. Currently we have one work queue that we | |
446 | * kick each time some resources are released, but it would | |
447 | * be fairly easy to have a per device one so that we only | |
448 | * need to attach to the conflicting device | |
449 | */ | |
450 | init_waitqueue_entry(&wait, current); | |
451 | add_wait_queue(&vga_wait_queue, &wait); | |
452 | set_current_state(interruptible ? | |
453 | TASK_INTERRUPTIBLE : | |
454 | TASK_UNINTERRUPTIBLE); | |
9f5bd308 KS |
455 | if (interruptible && signal_pending(current)) { |
456 | __set_current_state(TASK_RUNNING); | |
457 | remove_wait_queue(&vga_wait_queue, &wait); | |
458 | rc = -ERESTARTSYS; | |
deb2d2ec BH |
459 | break; |
460 | } | |
461 | schedule(); | |
462 | remove_wait_queue(&vga_wait_queue, &wait); | |
deb2d2ec BH |
463 | } |
464 | return rc; | |
465 | } | |
466 | EXPORT_SYMBOL(vga_get); | |
467 | ||
b754b35b DV |
468 | /** |
469 | * vga_tryget - try to acquire & lock legacy VGA resources | |
470 | * @pdev: pci devivce of VGA card or NULL for system default | |
471 | * @rsrc: bit mask of resources to acquire and lock | |
472 | * | |
473 | * This function performs the same operation as vga_get(), but will return an | |
474 | * error (-EBUSY) instead of blocking if the resources are already locked by | |
475 | * another card. It can be called in any context | |
476 | * | |
477 | * On success, release the VGA resource again with vga_put(). | |
478 | * | |
479 | * Returns: | |
480 | * | |
481 | * 0 on success, negative error code on failure. | |
482 | */ | |
deb2d2ec BH |
483 | int vga_tryget(struct pci_dev *pdev, unsigned int rsrc) |
484 | { | |
485 | struct vga_device *vgadev; | |
486 | unsigned long flags; | |
487 | int rc = 0; | |
488 | ||
489 | vga_check_first_use(); | |
490 | ||
491 | /* The one who calls us should check for this, but lets be sure... */ | |
492 | if (pdev == NULL) | |
493 | pdev = vga_default_device(); | |
494 | if (pdev == NULL) | |
495 | return 0; | |
496 | spin_lock_irqsave(&vga_lock, flags); | |
497 | vgadev = vgadev_find(pdev); | |
498 | if (vgadev == NULL) { | |
499 | rc = -ENODEV; | |
500 | goto bail; | |
501 | } | |
502 | if (__vga_tryget(vgadev, rsrc)) | |
503 | rc = -EBUSY; | |
504 | bail: | |
505 | spin_unlock_irqrestore(&vga_lock, flags); | |
506 | return rc; | |
507 | } | |
508 | EXPORT_SYMBOL(vga_tryget); | |
509 | ||
b754b35b DV |
510 | /** |
511 | * vga_put - release lock on legacy VGA resources | |
512 | * @pdev: pci device of VGA card or NULL for system default | |
513 | * @rsrc: but mask of resource to release | |
514 | * | |
515 | * This fuction releases resources previously locked by vga_get() or | |
516 | * vga_tryget(). The resources aren't disabled right away, so that a subsequence | |
517 | * vga_get() on the same card will succeed immediately. Resources have a | |
518 | * counter, so locks are only released if the counter reaches 0. | |
519 | */ | |
deb2d2ec BH |
520 | void vga_put(struct pci_dev *pdev, unsigned int rsrc) |
521 | { | |
522 | struct vga_device *vgadev; | |
523 | unsigned long flags; | |
524 | ||
525 | /* The one who calls us should check for this, but lets be sure... */ | |
526 | if (pdev == NULL) | |
527 | pdev = vga_default_device(); | |
528 | if (pdev == NULL) | |
529 | return; | |
530 | spin_lock_irqsave(&vga_lock, flags); | |
531 | vgadev = vgadev_find(pdev); | |
532 | if (vgadev == NULL) | |
533 | goto bail; | |
534 | __vga_put(vgadev, rsrc); | |
535 | bail: | |
536 | spin_unlock_irqrestore(&vga_lock, flags); | |
537 | } | |
538 | EXPORT_SYMBOL(vga_put); | |
539 | ||
5d90ccf9 TR |
540 | /* |
541 | * Rules for using a bridge to control a VGA descendant decoding: if a bridge | |
542 | * has only one VGA descendant then it can be used to control the VGA routing | |
543 | * for that device. It should always use the bridge closest to the device to | |
544 | * control it. If a bridge has a direct VGA descendant, but also have a sub- | |
545 | * bridge VGA descendant then we cannot use that bridge to control the direct | |
546 | * VGA descendant. So for every device we register, we need to iterate all | |
547 | * its parent bridges so we can invalidate any devices using them properly. | |
548 | */ | |
3448a19d DA |
549 | static void vga_arbiter_check_bridge_sharing(struct vga_device *vgadev) |
550 | { | |
551 | struct vga_device *same_bridge_vgadev; | |
552 | struct pci_bus *new_bus, *bus; | |
553 | struct pci_dev *new_bridge, *bridge; | |
554 | ||
555 | vgadev->bridge_has_one_vga = true; | |
556 | ||
557 | if (list_empty(&vga_list)) | |
558 | return; | |
559 | ||
560 | /* okay iterate the new devices bridge hierarachy */ | |
561 | new_bus = vgadev->pdev->bus; | |
562 | while (new_bus) { | |
563 | new_bridge = new_bus->self; | |
564 | ||
f6252114 DA |
565 | /* go through list of devices already registered */ |
566 | list_for_each_entry(same_bridge_vgadev, &vga_list, list) { | |
567 | bus = same_bridge_vgadev->pdev->bus; | |
568 | bridge = bus->self; | |
569 | ||
570 | /* see if the share a bridge with this device */ | |
571 | if (new_bridge == bridge) { | |
5d90ccf9 TR |
572 | /* |
573 | * If their direct parent bridge is the same | |
574 | * as any bridge of this device then it can't | |
575 | * be used for that device. | |
576 | */ | |
f6252114 DA |
577 | same_bridge_vgadev->bridge_has_one_vga = false; |
578 | } | |
3448a19d | 579 | |
5d90ccf9 TR |
580 | /* |
581 | * Now iterate the previous devices bridge hierarchy. | |
582 | * If the new devices parent bridge is in the other | |
583 | * devices hierarchy then we can't use it to control | |
584 | * this device | |
585 | */ | |
f6252114 DA |
586 | while (bus) { |
587 | bridge = bus->self; | |
5d90ccf9 TR |
588 | |
589 | if (bridge && bridge == vgadev->pdev->bus->self) | |
590 | vgadev->bridge_has_one_vga = false; | |
591 | ||
f6252114 | 592 | bus = bus->parent; |
3448a19d DA |
593 | } |
594 | } | |
595 | new_bus = new_bus->parent; | |
596 | } | |
597 | } | |
598 | ||
deb2d2ec BH |
599 | /* |
600 | * Currently, we assume that the "initial" setup of the system is | |
601 | * not sane, that is we come up with conflicting devices and let | |
602 | * the arbiter's client decides if devices decodes or not legacy | |
603 | * things. | |
604 | */ | |
605 | static bool vga_arbiter_add_pci_device(struct pci_dev *pdev) | |
606 | { | |
607 | struct vga_device *vgadev; | |
608 | unsigned long flags; | |
609 | struct pci_bus *bus; | |
610 | struct pci_dev *bridge; | |
611 | u16 cmd; | |
612 | ||
613 | /* Only deal with VGA class devices */ | |
614 | if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA) | |
615 | return false; | |
616 | ||
617 | /* Allocate structure */ | |
945ef5bb | 618 | vgadev = kzalloc(sizeof(struct vga_device), GFP_KERNEL); |
deb2d2ec | 619 | if (vgadev == NULL) { |
a75d68f6 | 620 | vgaarb_err(&pdev->dev, "failed to allocate VGA arbiter data\n"); |
5d90ccf9 TR |
621 | /* |
622 | * What to do on allocation failure ? For now, let's just do | |
623 | * nothing, I'm not sure there is anything saner to be done. | |
deb2d2ec BH |
624 | */ |
625 | return false; | |
626 | } | |
627 | ||
deb2d2ec BH |
628 | /* Take lock & check for duplicates */ |
629 | spin_lock_irqsave(&vga_lock, flags); | |
630 | if (vgadev_find(pdev) != NULL) { | |
631 | BUG_ON(1); | |
632 | goto fail; | |
633 | } | |
634 | vgadev->pdev = pdev; | |
635 | ||
636 | /* By default, assume we decode everything */ | |
637 | vgadev->decodes = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM | | |
638 | VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM; | |
639 | ||
640 | /* by default mark it as decoding */ | |
641 | vga_decode_count++; | |
642 | /* Mark that we "own" resources based on our enables, we will | |
643 | * clear that below if the bridge isn't forwarding | |
644 | */ | |
645 | pci_read_config_word(pdev, PCI_COMMAND, &cmd); | |
646 | if (cmd & PCI_COMMAND_IO) | |
647 | vgadev->owns |= VGA_RSRC_LEGACY_IO; | |
648 | if (cmd & PCI_COMMAND_MEMORY) | |
649 | vgadev->owns |= VGA_RSRC_LEGACY_MEM; | |
650 | ||
651 | /* Check if VGA cycles can get down to us */ | |
652 | bus = pdev->bus; | |
653 | while (bus) { | |
654 | bridge = bus->self; | |
655 | if (bridge) { | |
656 | u16 l; | |
5d90ccf9 TR |
657 | |
658 | pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, &l); | |
deb2d2ec BH |
659 | if (!(l & PCI_BRIDGE_CTL_VGA)) { |
660 | vgadev->owns = 0; | |
661 | break; | |
662 | } | |
663 | } | |
664 | bus = bus->parent; | |
665 | } | |
666 | ||
667 | /* Deal with VGA default device. Use first enabled one | |
668 | * by default if arch doesn't have it's own hook | |
669 | */ | |
deb2d2ec | 670 | if (vga_default == NULL && |
86fd887b | 671 | ((vgadev->owns & VGA_RSRC_LEGACY_MASK) == VGA_RSRC_LEGACY_MASK)) { |
a75d68f6 | 672 | vgaarb_info(&pdev->dev, "setting as boot VGA device\n"); |
84544a1d | 673 | vga_set_default_device(pdev); |
86fd887b | 674 | } |
deb2d2ec | 675 | |
3448a19d DA |
676 | vga_arbiter_check_bridge_sharing(vgadev); |
677 | ||
deb2d2ec BH |
678 | /* Add to the list */ |
679 | list_add(&vgadev->list, &vga_list); | |
680 | vga_count++; | |
a75d68f6 | 681 | vgaarb_info(&pdev->dev, "VGA device added: decodes=%s,owns=%s,locks=%s\n", |
deb2d2ec BH |
682 | vga_iostate_to_str(vgadev->decodes), |
683 | vga_iostate_to_str(vgadev->owns), | |
684 | vga_iostate_to_str(vgadev->locks)); | |
685 | ||
686 | spin_unlock_irqrestore(&vga_lock, flags); | |
687 | return true; | |
688 | fail: | |
689 | spin_unlock_irqrestore(&vga_lock, flags); | |
690 | kfree(vgadev); | |
691 | return false; | |
692 | } | |
693 | ||
694 | static bool vga_arbiter_del_pci_device(struct pci_dev *pdev) | |
695 | { | |
696 | struct vga_device *vgadev; | |
697 | unsigned long flags; | |
698 | bool ret = true; | |
699 | ||
700 | spin_lock_irqsave(&vga_lock, flags); | |
701 | vgadev = vgadev_find(pdev); | |
702 | if (vgadev == NULL) { | |
703 | ret = false; | |
704 | goto bail; | |
705 | } | |
706 | ||
84544a1d YL |
707 | if (vga_default == pdev) |
708 | vga_set_default_device(NULL); | |
deb2d2ec BH |
709 | |
710 | if (vgadev->decodes & (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)) | |
711 | vga_decode_count--; | |
712 | ||
713 | /* Remove entry from list */ | |
714 | list_del(&vgadev->list); | |
715 | vga_count--; | |
716 | /* Notify userland driver that the device is gone so it discards | |
717 | * it's copies of the pci_dev pointer | |
718 | */ | |
719 | vga_arb_device_card_gone(pdev); | |
720 | ||
721 | /* Wake up all possible waiters */ | |
722 | wake_up_all(&vga_wait_queue); | |
723 | bail: | |
724 | spin_unlock_irqrestore(&vga_lock, flags); | |
725 | kfree(vgadev); | |
726 | return ret; | |
727 | } | |
728 | ||
729 | /* this is called with the lock */ | |
730 | static inline void vga_update_device_decodes(struct vga_device *vgadev, | |
731 | int new_decodes) | |
732 | { | |
a75d68f6 | 733 | struct device *dev = &vgadev->pdev->dev; |
5c0f6ee7 | 734 | int old_decodes, decodes_removed, decodes_unlocked; |
deb2d2ec BH |
735 | |
736 | old_decodes = vgadev->decodes; | |
5c0f6ee7 AW |
737 | decodes_removed = ~new_decodes & old_decodes; |
738 | decodes_unlocked = vgadev->locks & decodes_removed; | |
deb2d2ec BH |
739 | vgadev->decodes = new_decodes; |
740 | ||
a75d68f6 | 741 | vgaarb_info(dev, "changed VGA decodes: olddecodes=%s,decodes=%s:owns=%s\n", |
deb2d2ec BH |
742 | vga_iostate_to_str(old_decodes), |
743 | vga_iostate_to_str(vgadev->decodes), | |
744 | vga_iostate_to_str(vgadev->owns)); | |
745 | ||
5c0f6ee7 AW |
746 | /* if we removed locked decodes, lock count goes to zero, and release */ |
747 | if (decodes_unlocked) { | |
748 | if (decodes_unlocked & VGA_RSRC_LEGACY_IO) | |
749 | vgadev->io_lock_cnt = 0; | |
750 | if (decodes_unlocked & VGA_RSRC_LEGACY_MEM) | |
751 | vgadev->mem_lock_cnt = 0; | |
752 | __vga_put(vgadev, decodes_unlocked); | |
deb2d2ec BH |
753 | } |
754 | ||
755 | /* change decodes counter */ | |
5c0f6ee7 AW |
756 | if (old_decodes & VGA_RSRC_LEGACY_MASK && |
757 | !(new_decodes & VGA_RSRC_LEGACY_MASK)) | |
758 | vga_decode_count--; | |
759 | if (!(old_decodes & VGA_RSRC_LEGACY_MASK) && | |
760 | new_decodes & VGA_RSRC_LEGACY_MASK) | |
761 | vga_decode_count++; | |
a75d68f6 | 762 | vgaarb_dbg(dev, "decoding count now is: %d\n", vga_decode_count); |
deb2d2ec BH |
763 | } |
764 | ||
5d90ccf9 TR |
765 | static void __vga_set_legacy_decoding(struct pci_dev *pdev, |
766 | unsigned int decodes, | |
767 | bool userspace) | |
deb2d2ec BH |
768 | { |
769 | struct vga_device *vgadev; | |
770 | unsigned long flags; | |
771 | ||
772 | decodes &= VGA_RSRC_LEGACY_MASK; | |
773 | ||
774 | spin_lock_irqsave(&vga_lock, flags); | |
775 | vgadev = vgadev_find(pdev); | |
776 | if (vgadev == NULL) | |
777 | goto bail; | |
778 | ||
779 | /* don't let userspace futz with kernel driver decodes */ | |
780 | if (userspace && vgadev->set_vga_decode) | |
781 | goto bail; | |
782 | ||
783 | /* update the device decodes + counter */ | |
784 | vga_update_device_decodes(vgadev, decodes); | |
785 | ||
786 | /* XXX if somebody is going from "doesn't decode" to "decodes" state | |
787 | * here, additional care must be taken as we may have pending owner | |
788 | * ship of non-legacy region ... | |
789 | */ | |
790 | bail: | |
791 | spin_unlock_irqrestore(&vga_lock, flags); | |
792 | } | |
793 | ||
794 | void vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes) | |
795 | { | |
796 | __vga_set_legacy_decoding(pdev, decodes, false); | |
797 | } | |
798 | EXPORT_SYMBOL(vga_set_legacy_decoding); | |
799 | ||
b754b35b DV |
800 | /** |
801 | * vga_client_register - register or unregister a VGA arbitration client | |
802 | * @pdev: pci device of the VGA client | |
803 | * @cookie: client cookie to be used in callbacks | |
804 | * @irq_set_state: irq state change callback | |
805 | * @set_vga_decode: vga decode change callback | |
806 | * | |
807 | * Clients have two callback mechanisms they can use. | |
808 | * | |
809 | * @irq_set_state callback: If a client can't disable its GPUs VGA | |
810 | * resources, then we need to be able to ask it to turn off its irqs when we | |
811 | * turn off its mem and io decoding. | |
812 | * | |
813 | * @set_vga_decode callback: If a client can disable its GPU VGA resource, it | |
814 | * will get a callback from this to set the encode/decode state. | |
815 | * | |
816 | * Rationale: we cannot disable VGA decode resources unconditionally some single | |
817 | * GPU laptops seem to require ACPI or BIOS access to the VGA registers to | |
818 | * control things like backlights etc. Hopefully newer multi-GPU laptops do | |
819 | * something saner, and desktops won't have any special ACPI for this. The | |
820 | * driver will get a callback when VGA arbitration is first used by userspace | |
821 | * since some older X servers have issues. | |
822 | * | |
823 | * This function does not check whether a client for @pdev has been registered | |
824 | * already. | |
825 | * | |
826 | * To unregister just call this function with @irq_set_state and @set_vga_decode | |
827 | * both set to NULL for the same @pdev as originally used to register them. | |
828 | * | |
829 | * Returns: 0 on success, -1 on failure | |
830 | */ | |
deb2d2ec BH |
831 | int vga_client_register(struct pci_dev *pdev, void *cookie, |
832 | void (*irq_set_state)(void *cookie, bool state), | |
5d90ccf9 TR |
833 | unsigned int (*set_vga_decode)(void *cookie, |
834 | bool decode)) | |
deb2d2ec | 835 | { |
934f992c | 836 | int ret = -ENODEV; |
deb2d2ec BH |
837 | struct vga_device *vgadev; |
838 | unsigned long flags; | |
839 | ||
840 | spin_lock_irqsave(&vga_lock, flags); | |
841 | vgadev = vgadev_find(pdev); | |
842 | if (!vgadev) | |
843 | goto bail; | |
844 | ||
845 | vgadev->irq_set_state = irq_set_state; | |
846 | vgadev->set_vga_decode = set_vga_decode; | |
847 | vgadev->cookie = cookie; | |
848 | ret = 0; | |
849 | ||
850 | bail: | |
851 | spin_unlock_irqrestore(&vga_lock, flags); | |
852 | return ret; | |
853 | ||
854 | } | |
855 | EXPORT_SYMBOL(vga_client_register); | |
856 | ||
857 | /* | |
858 | * Char driver implementation | |
859 | * | |
860 | * Semantics is: | |
861 | * | |
862 | * open : open user instance of the arbitrer. by default, it's | |
863 | * attached to the default VGA device of the system. | |
864 | * | |
865 | * close : close user instance, release locks | |
866 | * | |
867 | * read : return a string indicating the status of the target. | |
868 | * an IO state string is of the form {io,mem,io+mem,none}, | |
869 | * mc and ic are respectively mem and io lock counts (for | |
870 | * debugging/diagnostic only). "decodes" indicate what the | |
871 | * card currently decodes, "owns" indicates what is currently | |
872 | * enabled on it, and "locks" indicates what is locked by this | |
873 | * card. If the card is unplugged, we get "invalid" then for | |
874 | * card_ID and an -ENODEV error is returned for any command | |
875 | * until a new card is targeted | |
876 | * | |
877 | * "<card_ID>,decodes=<io_state>,owns=<io_state>,locks=<io_state> (ic,mc)" | |
878 | * | |
879 | * write : write a command to the arbiter. List of commands is: | |
880 | * | |
881 | * target <card_ID> : switch target to card <card_ID> (see below) | |
882 | * lock <io_state> : acquires locks on target ("none" is invalid io_state) | |
883 | * trylock <io_state> : non-blocking acquire locks on target | |
884 | * unlock <io_state> : release locks on target | |
885 | * unlock all : release all locks on target held by this user | |
886 | * decodes <io_state> : set the legacy decoding attributes for the card | |
887 | * | |
888 | * poll : event if something change on any card (not just the target) | |
889 | * | |
890 | * card_ID is of the form "PCI:domain:bus:dev.fn". It can be set to "default" | |
891 | * to go back to the system default card (TODO: not implemented yet). | |
892 | * Currently, only PCI is supported as a prefix, but the userland API may | |
893 | * support other bus types in the future, even if the current kernel | |
894 | * implementation doesn't. | |
895 | * | |
896 | * Note about locks: | |
897 | * | |
898 | * The driver keeps track of which user has what locks on which card. It | |
899 | * supports stacking, like the kernel one. This complexifies the implementation | |
900 | * a bit, but makes the arbiter more tolerant to userspace problems and able | |
901 | * to properly cleanup in all cases when a process dies. | |
902 | * Currently, a max of 16 cards simultaneously can have locks issued from | |
903 | * userspace for a given user (file descriptor instance) of the arbiter. | |
904 | * | |
905 | * If the device is hot-unplugged, there is a hook inside the module to notify | |
906 | * they being added/removed in the system and automatically added/removed in | |
907 | * the arbiter. | |
908 | */ | |
909 | ||
36028f33 | 910 | #define MAX_USER_CARDS CONFIG_VGA_ARB_MAX_GPUS |
deb2d2ec BH |
911 | #define PCI_INVALID_CARD ((struct pci_dev *)-1UL) |
912 | ||
913 | /* | |
914 | * Each user has an array of these, tracking which cards have locks | |
915 | */ | |
916 | struct vga_arb_user_card { | |
917 | struct pci_dev *pdev; | |
918 | unsigned int mem_cnt; | |
919 | unsigned int io_cnt; | |
920 | }; | |
921 | ||
922 | struct vga_arb_private { | |
923 | struct list_head list; | |
924 | struct pci_dev *target; | |
925 | struct vga_arb_user_card cards[MAX_USER_CARDS]; | |
926 | spinlock_t lock; | |
927 | }; | |
928 | ||
929 | static LIST_HEAD(vga_user_list); | |
930 | static DEFINE_SPINLOCK(vga_user_lock); | |
931 | ||
932 | ||
933 | /* | |
934 | * This function gets a string in the format: "PCI:domain:bus:dev.fn" and | |
935 | * returns the respective values. If the string is not in this format, | |
936 | * it returns 0. | |
937 | */ | |
938 | static int vga_pci_str_to_vars(char *buf, int count, unsigned int *domain, | |
939 | unsigned int *bus, unsigned int *devfn) | |
940 | { | |
941 | int n; | |
942 | unsigned int slot, func; | |
943 | ||
944 | ||
945 | n = sscanf(buf, "PCI:%x:%x:%x.%x", domain, bus, &slot, &func); | |
946 | if (n != 4) | |
947 | return 0; | |
948 | ||
949 | *devfn = PCI_DEVFN(slot, func); | |
950 | ||
951 | return 1; | |
952 | } | |
953 | ||
5d90ccf9 | 954 | static ssize_t vga_arb_read(struct file *file, char __user *buf, |
deb2d2ec BH |
955 | size_t count, loff_t *ppos) |
956 | { | |
957 | struct vga_arb_private *priv = file->private_data; | |
958 | struct vga_device *vgadev; | |
959 | struct pci_dev *pdev; | |
960 | unsigned long flags; | |
961 | size_t len; | |
962 | int rc; | |
963 | char *lbuf; | |
964 | ||
965 | lbuf = kmalloc(1024, GFP_KERNEL); | |
966 | if (lbuf == NULL) | |
967 | return -ENOMEM; | |
968 | ||
969 | /* Shields against vga_arb_device_card_gone (pci_dev going | |
970 | * away), and allows access to vga list | |
971 | */ | |
972 | spin_lock_irqsave(&vga_lock, flags); | |
973 | ||
25985edc | 974 | /* If we are targeting the default, use it */ |
deb2d2ec BH |
975 | pdev = priv->target; |
976 | if (pdev == NULL || pdev == PCI_INVALID_CARD) { | |
977 | spin_unlock_irqrestore(&vga_lock, flags); | |
978 | len = sprintf(lbuf, "invalid"); | |
979 | goto done; | |
980 | } | |
981 | ||
982 | /* Find card vgadev structure */ | |
983 | vgadev = vgadev_find(pdev); | |
984 | if (vgadev == NULL) { | |
985 | /* Wow, it's not in the list, that shouldn't happen, | |
986 | * let's fix us up and return invalid card | |
987 | */ | |
988 | if (pdev == priv->target) | |
989 | vga_arb_device_card_gone(pdev); | |
990 | spin_unlock_irqrestore(&vga_lock, flags); | |
991 | len = sprintf(lbuf, "invalid"); | |
992 | goto done; | |
993 | } | |
994 | ||
995 | /* Fill the buffer with infos */ | |
996 | len = snprintf(lbuf, 1024, | |
997 | "count:%d,PCI:%s,decodes=%s,owns=%s,locks=%s(%d:%d)\n", | |
998 | vga_decode_count, pci_name(pdev), | |
999 | vga_iostate_to_str(vgadev->decodes), | |
1000 | vga_iostate_to_str(vgadev->owns), | |
1001 | vga_iostate_to_str(vgadev->locks), | |
1002 | vgadev->io_lock_cnt, vgadev->mem_lock_cnt); | |
1003 | ||
1004 | spin_unlock_irqrestore(&vga_lock, flags); | |
1005 | done: | |
1006 | ||
1007 | /* Copy that to user */ | |
1008 | if (len > count) | |
1009 | len = count; | |
1010 | rc = copy_to_user(buf, lbuf, len); | |
1011 | kfree(lbuf); | |
1012 | if (rc) | |
1013 | return -EFAULT; | |
1014 | return len; | |
1015 | } | |
1016 | ||
1017 | /* | |
1018 | * TODO: To avoid parsing inside kernel and to improve the speed we may | |
1019 | * consider use ioctl here | |
1020 | */ | |
5d90ccf9 | 1021 | static ssize_t vga_arb_write(struct file *file, const char __user *buf, |
deb2d2ec BH |
1022 | size_t count, loff_t *ppos) |
1023 | { | |
1024 | struct vga_arb_private *priv = file->private_data; | |
1025 | struct vga_arb_user_card *uc = NULL; | |
1026 | struct pci_dev *pdev; | |
1027 | ||
1028 | unsigned int io_state; | |
1029 | ||
49521b13 | 1030 | char kbuf[64], *curr_pos; |
deb2d2ec BH |
1031 | size_t remaining = count; |
1032 | ||
1033 | int ret_val; | |
1034 | int i; | |
1035 | ||
49521b13 DV |
1036 | if (count >= sizeof(kbuf)) |
1037 | return -EINVAL; | |
1038 | if (copy_from_user(kbuf, buf, count)) | |
deb2d2ec | 1039 | return -EFAULT; |
deb2d2ec BH |
1040 | curr_pos = kbuf; |
1041 | kbuf[count] = '\0'; /* Just to make sure... */ | |
1042 | ||
1043 | if (strncmp(curr_pos, "lock ", 5) == 0) { | |
1044 | curr_pos += 5; | |
1045 | remaining -= 5; | |
1046 | ||
2d6e9b91 | 1047 | pr_debug("client 0x%p called 'lock'\n", priv); |
deb2d2ec BH |
1048 | |
1049 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1050 | ret_val = -EPROTO; | |
1051 | goto done; | |
1052 | } | |
1053 | if (io_state == VGA_RSRC_NONE) { | |
1054 | ret_val = -EPROTO; | |
1055 | goto done; | |
1056 | } | |
1057 | ||
1058 | pdev = priv->target; | |
1059 | if (priv->target == NULL) { | |
1060 | ret_val = -ENODEV; | |
1061 | goto done; | |
1062 | } | |
1063 | ||
1064 | vga_get_uninterruptible(pdev, io_state); | |
1065 | ||
1066 | /* Update the client's locks lists... */ | |
1067 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1068 | if (priv->cards[i].pdev == pdev) { | |
1069 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1070 | priv->cards[i].io_cnt++; | |
1071 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1072 | priv->cards[i].mem_cnt++; | |
1073 | break; | |
1074 | } | |
1075 | } | |
1076 | ||
1077 | ret_val = count; | |
1078 | goto done; | |
1079 | } else if (strncmp(curr_pos, "unlock ", 7) == 0) { | |
1080 | curr_pos += 7; | |
1081 | remaining -= 7; | |
1082 | ||
2d6e9b91 | 1083 | pr_debug("client 0x%p called 'unlock'\n", priv); |
deb2d2ec BH |
1084 | |
1085 | if (strncmp(curr_pos, "all", 3) == 0) | |
1086 | io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
1087 | else { | |
1088 | if (!vga_str_to_iostate | |
1089 | (curr_pos, remaining, &io_state)) { | |
1090 | ret_val = -EPROTO; | |
1091 | goto done; | |
1092 | } | |
1093 | /* TODO: Add this? | |
1094 | if (io_state == VGA_RSRC_NONE) { | |
1095 | ret_val = -EPROTO; | |
1096 | goto done; | |
1097 | } | |
1098 | */ | |
1099 | } | |
1100 | ||
1101 | pdev = priv->target; | |
1102 | if (priv->target == NULL) { | |
1103 | ret_val = -ENODEV; | |
1104 | goto done; | |
1105 | } | |
1106 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1107 | if (priv->cards[i].pdev == pdev) | |
1108 | uc = &priv->cards[i]; | |
1109 | } | |
1110 | ||
c916874d JL |
1111 | if (!uc) { |
1112 | ret_val = -EINVAL; | |
1113 | goto done; | |
1114 | } | |
deb2d2ec | 1115 | |
c916874d JL |
1116 | if (io_state & VGA_RSRC_LEGACY_IO && uc->io_cnt == 0) { |
1117 | ret_val = -EINVAL; | |
1118 | goto done; | |
1119 | } | |
deb2d2ec | 1120 | |
c916874d JL |
1121 | if (io_state & VGA_RSRC_LEGACY_MEM && uc->mem_cnt == 0) { |
1122 | ret_val = -EINVAL; | |
1123 | goto done; | |
1124 | } | |
deb2d2ec BH |
1125 | |
1126 | vga_put(pdev, io_state); | |
1127 | ||
1128 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1129 | uc->io_cnt--; | |
1130 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1131 | uc->mem_cnt--; | |
1132 | ||
1133 | ret_val = count; | |
1134 | goto done; | |
1135 | } else if (strncmp(curr_pos, "trylock ", 8) == 0) { | |
1136 | curr_pos += 8; | |
1137 | remaining -= 8; | |
1138 | ||
2d6e9b91 | 1139 | pr_debug("client 0x%p called 'trylock'\n", priv); |
deb2d2ec BH |
1140 | |
1141 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1142 | ret_val = -EPROTO; | |
1143 | goto done; | |
1144 | } | |
1145 | /* TODO: Add this? | |
1146 | if (io_state == VGA_RSRC_NONE) { | |
1147 | ret_val = -EPROTO; | |
1148 | goto done; | |
1149 | } | |
1150 | */ | |
1151 | ||
1152 | pdev = priv->target; | |
1153 | if (priv->target == NULL) { | |
1154 | ret_val = -ENODEV; | |
1155 | goto done; | |
1156 | } | |
1157 | ||
1158 | if (vga_tryget(pdev, io_state)) { | |
1159 | /* Update the client's locks lists... */ | |
1160 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1161 | if (priv->cards[i].pdev == pdev) { | |
1162 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1163 | priv->cards[i].io_cnt++; | |
1164 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1165 | priv->cards[i].mem_cnt++; | |
1166 | break; | |
1167 | } | |
1168 | } | |
1169 | ret_val = count; | |
1170 | goto done; | |
1171 | } else { | |
1172 | ret_val = -EBUSY; | |
1173 | goto done; | |
1174 | } | |
1175 | ||
1176 | } else if (strncmp(curr_pos, "target ", 7) == 0) { | |
1177 | unsigned int domain, bus, devfn; | |
1178 | struct vga_device *vgadev; | |
1179 | ||
1180 | curr_pos += 7; | |
1181 | remaining -= 7; | |
2d6e9b91 | 1182 | pr_debug("client 0x%p called 'target'\n", priv); |
deb2d2ec | 1183 | /* if target is default */ |
2cc9116c | 1184 | if (!strncmp(curr_pos, "default", 7)) |
deb2d2ec BH |
1185 | pdev = pci_dev_get(vga_default_device()); |
1186 | else { | |
1187 | if (!vga_pci_str_to_vars(curr_pos, remaining, | |
1188 | &domain, &bus, &devfn)) { | |
1189 | ret_val = -EPROTO; | |
1190 | goto done; | |
1191 | } | |
f85567c8 | 1192 | pdev = pci_get_domain_bus_and_slot(domain, bus, devfn); |
deb2d2ec | 1193 | if (!pdev) { |
cf590b87 BH |
1194 | pr_debug("invalid PCI address %04x:%02x:%02x.%x\n", |
1195 | domain, bus, PCI_SLOT(devfn), | |
1196 | PCI_FUNC(devfn)); | |
deb2d2ec BH |
1197 | ret_val = -ENODEV; |
1198 | goto done; | |
1199 | } | |
a75d68f6 BH |
1200 | |
1201 | pr_debug("%s ==> %04x:%02x:%02x.%x pdev %p\n", curr_pos, | |
1202 | domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn), | |
1203 | pdev); | |
deb2d2ec BH |
1204 | } |
1205 | ||
1206 | vgadev = vgadev_find(pdev); | |
8b7e2e86 | 1207 | pr_debug("vgadev %p\n", vgadev); |
deb2d2ec | 1208 | if (vgadev == NULL) { |
eb6944f2 | 1209 | if (pdev) { |
cf590b87 | 1210 | vgaarb_dbg(&pdev->dev, "not a VGA device\n"); |
eb6944f2 TR |
1211 | pci_dev_put(pdev); |
1212 | } | |
1213 | ||
deb2d2ec BH |
1214 | ret_val = -ENODEV; |
1215 | goto done; | |
1216 | } | |
1217 | ||
1218 | priv->target = pdev; | |
1219 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1220 | if (priv->cards[i].pdev == pdev) | |
1221 | break; | |
1222 | if (priv->cards[i].pdev == NULL) { | |
1223 | priv->cards[i].pdev = pdev; | |
1224 | priv->cards[i].io_cnt = 0; | |
1225 | priv->cards[i].mem_cnt = 0; | |
1226 | break; | |
1227 | } | |
1228 | } | |
1229 | if (i == MAX_USER_CARDS) { | |
cf590b87 | 1230 | vgaarb_dbg(&pdev->dev, "maximum user cards (%d) number reached, ignoring this one!\n", |
773a38db | 1231 | MAX_USER_CARDS); |
deb2d2ec BH |
1232 | pci_dev_put(pdev); |
1233 | /* XXX: which value to return? */ | |
1234 | ret_val = -ENOMEM; | |
1235 | goto done; | |
1236 | } | |
1237 | ||
1238 | ret_val = count; | |
1239 | pci_dev_put(pdev); | |
1240 | goto done; | |
1241 | ||
1242 | ||
1243 | } else if (strncmp(curr_pos, "decodes ", 8) == 0) { | |
1244 | curr_pos += 8; | |
1245 | remaining -= 8; | |
8b7e2e86 | 1246 | pr_debug("client 0x%p called 'decodes'\n", priv); |
deb2d2ec BH |
1247 | |
1248 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1249 | ret_val = -EPROTO; | |
1250 | goto done; | |
1251 | } | |
1252 | pdev = priv->target; | |
1253 | if (priv->target == NULL) { | |
1254 | ret_val = -ENODEV; | |
1255 | goto done; | |
1256 | } | |
1257 | ||
1258 | __vga_set_legacy_decoding(pdev, io_state, true); | |
1259 | ret_val = count; | |
1260 | goto done; | |
1261 | } | |
1262 | /* If we got here, the message written is not part of the protocol! */ | |
deb2d2ec BH |
1263 | return -EPROTO; |
1264 | ||
1265 | done: | |
deb2d2ec BH |
1266 | return ret_val; |
1267 | } | |
1268 | ||
5d90ccf9 | 1269 | static unsigned int vga_arb_fpoll(struct file *file, poll_table *wait) |
deb2d2ec | 1270 | { |
2d6e9b91 | 1271 | pr_debug("%s\n", __func__); |
deb2d2ec | 1272 | |
deb2d2ec BH |
1273 | poll_wait(file, &vga_wait_queue, wait); |
1274 | return POLLIN; | |
1275 | } | |
1276 | ||
1277 | static int vga_arb_open(struct inode *inode, struct file *file) | |
1278 | { | |
1279 | struct vga_arb_private *priv; | |
1280 | unsigned long flags; | |
1281 | ||
2d6e9b91 | 1282 | pr_debug("%s\n", __func__); |
deb2d2ec | 1283 | |
f35119d6 | 1284 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); |
deb2d2ec BH |
1285 | if (priv == NULL) |
1286 | return -ENOMEM; | |
deb2d2ec BH |
1287 | spin_lock_init(&priv->lock); |
1288 | file->private_data = priv; | |
1289 | ||
1290 | spin_lock_irqsave(&vga_user_lock, flags); | |
1291 | list_add(&priv->list, &vga_user_list); | |
1292 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1293 | ||
1294 | /* Set the client' lists of locks */ | |
1295 | priv->target = vga_default_device(); /* Maybe this is still null! */ | |
1296 | priv->cards[0].pdev = priv->target; | |
1297 | priv->cards[0].io_cnt = 0; | |
1298 | priv->cards[0].mem_cnt = 0; | |
1299 | ||
1300 | ||
1301 | return 0; | |
1302 | } | |
1303 | ||
1304 | static int vga_arb_release(struct inode *inode, struct file *file) | |
1305 | { | |
1306 | struct vga_arb_private *priv = file->private_data; | |
1307 | struct vga_arb_user_card *uc; | |
1308 | unsigned long flags; | |
1309 | int i; | |
1310 | ||
2d6e9b91 | 1311 | pr_debug("%s\n", __func__); |
deb2d2ec | 1312 | |
deb2d2ec BH |
1313 | spin_lock_irqsave(&vga_user_lock, flags); |
1314 | list_del(&priv->list); | |
1315 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1316 | uc = &priv->cards[i]; | |
1317 | if (uc->pdev == NULL) | |
1318 | continue; | |
a75d68f6 BH |
1319 | vgaarb_dbg(&uc->pdev->dev, "uc->io_cnt == %d, uc->mem_cnt == %d\n", |
1320 | uc->io_cnt, uc->mem_cnt); | |
deb2d2ec BH |
1321 | while (uc->io_cnt--) |
1322 | vga_put(uc->pdev, VGA_RSRC_LEGACY_IO); | |
1323 | while (uc->mem_cnt--) | |
1324 | vga_put(uc->pdev, VGA_RSRC_LEGACY_MEM); | |
1325 | } | |
1326 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1327 | ||
1328 | kfree(priv); | |
1329 | ||
1330 | return 0; | |
1331 | } | |
1332 | ||
1333 | static void vga_arb_device_card_gone(struct pci_dev *pdev) | |
1334 | { | |
1335 | } | |
1336 | ||
1337 | /* | |
1338 | * callback any registered clients to let them know we have a | |
1339 | * change in VGA cards | |
1340 | */ | |
1341 | static void vga_arbiter_notify_clients(void) | |
1342 | { | |
1343 | struct vga_device *vgadev; | |
1344 | unsigned long flags; | |
1345 | uint32_t new_decodes; | |
1346 | bool new_state; | |
1347 | ||
1348 | if (!vga_arbiter_used) | |
1349 | return; | |
1350 | ||
1351 | spin_lock_irqsave(&vga_lock, flags); | |
1352 | list_for_each_entry(vgadev, &vga_list, list) { | |
1353 | if (vga_count > 1) | |
1354 | new_state = false; | |
1355 | else | |
1356 | new_state = true; | |
1357 | if (vgadev->set_vga_decode) { | |
5d90ccf9 TR |
1358 | new_decodes = vgadev->set_vga_decode(vgadev->cookie, |
1359 | new_state); | |
deb2d2ec BH |
1360 | vga_update_device_decodes(vgadev, new_decodes); |
1361 | } | |
1362 | } | |
1363 | spin_unlock_irqrestore(&vga_lock, flags); | |
1364 | } | |
1365 | ||
1366 | static int pci_notify(struct notifier_block *nb, unsigned long action, | |
1367 | void *data) | |
1368 | { | |
1369 | struct device *dev = data; | |
1370 | struct pci_dev *pdev = to_pci_dev(dev); | |
1371 | bool notify = false; | |
1372 | ||
a75d68f6 | 1373 | vgaarb_dbg(dev, "%s\n", __func__); |
deb2d2ec BH |
1374 | |
1375 | /* For now we're only intereted in devices added and removed. I didn't | |
1376 | * test this thing here, so someone needs to double check for the | |
1377 | * cases of hotplugable vga cards. */ | |
1378 | if (action == BUS_NOTIFY_ADD_DEVICE) | |
1379 | notify = vga_arbiter_add_pci_device(pdev); | |
1380 | else if (action == BUS_NOTIFY_DEL_DEVICE) | |
1381 | notify = vga_arbiter_del_pci_device(pdev); | |
1382 | ||
1383 | if (notify) | |
1384 | vga_arbiter_notify_clients(); | |
1385 | return 0; | |
1386 | } | |
1387 | ||
1388 | static struct notifier_block pci_notifier = { | |
1389 | .notifier_call = pci_notify, | |
1390 | }; | |
1391 | ||
1392 | static const struct file_operations vga_arb_device_fops = { | |
1393 | .read = vga_arb_read, | |
1394 | .write = vga_arb_write, | |
1395 | .poll = vga_arb_fpoll, | |
1396 | .open = vga_arb_open, | |
1397 | .release = vga_arb_release, | |
6038f373 | 1398 | .llseek = noop_llseek, |
deb2d2ec BH |
1399 | }; |
1400 | ||
1401 | static struct miscdevice vga_arb_device = { | |
1402 | MISC_DYNAMIC_MINOR, "vga_arbiter", &vga_arb_device_fops | |
1403 | }; | |
1404 | ||
1405 | static int __init vga_arb_device_init(void) | |
1406 | { | |
1407 | int rc; | |
1408 | struct pci_dev *pdev; | |
3448a19d | 1409 | struct vga_device *vgadev; |
deb2d2ec BH |
1410 | |
1411 | rc = misc_register(&vga_arb_device); | |
1412 | if (rc < 0) | |
8b7e2e86 | 1413 | pr_err("error %d registering device\n", rc); |
deb2d2ec BH |
1414 | |
1415 | bus_register_notifier(&pci_bus_type, &pci_notifier); | |
1416 | ||
1417 | /* We add all pci devices satisfying vga class in the arbiter by | |
1418 | * default */ | |
1419 | pdev = NULL; | |
1420 | while ((pdev = | |
1421 | pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, | |
1422 | PCI_ANY_ID, pdev)) != NULL) | |
1423 | vga_arbiter_add_pci_device(pdev); | |
1424 | ||
3448a19d | 1425 | list_for_each_entry(vgadev, &vga_list, list) { |
ed2ab35e | 1426 | struct device *dev = &vgadev->pdev->dev; |
86fd887b | 1427 | #if defined(CONFIG_X86) || defined(CONFIG_IA64) |
5d90ccf9 TR |
1428 | /* |
1429 | * Override vga_arbiter_add_pci_device()'s I/O based detection | |
1430 | * as it may take the wrong device (e.g. on Apple system under | |
1431 | * EFI). | |
86fd887b | 1432 | * |
5d90ccf9 TR |
1433 | * Select the device owning the boot framebuffer if there is |
1434 | * one. | |
86fd887b | 1435 | */ |
5d90ccf9 TR |
1436 | resource_size_t start, end, limit; |
1437 | unsigned long flags; | |
86fd887b BP |
1438 | int i; |
1439 | ||
5d90ccf9 TR |
1440 | limit = screen_info.lfb_base + screen_info.lfb_size; |
1441 | ||
86fd887b BP |
1442 | /* Does firmware framebuffer belong to us? */ |
1443 | for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) { | |
5d90ccf9 TR |
1444 | flags = pci_resource_flags(vgadev->pdev, i); |
1445 | ||
1446 | if ((flags & IORESOURCE_MEM) == 0) | |
86fd887b BP |
1447 | continue; |
1448 | ||
1449 | start = pci_resource_start(vgadev->pdev, i); | |
1450 | end = pci_resource_end(vgadev->pdev, i); | |
1451 | ||
1452 | if (!start || !end) | |
1453 | continue; | |
1454 | ||
5d90ccf9 | 1455 | if (screen_info.lfb_base < start || limit >= end) |
86fd887b | 1456 | continue; |
5d90ccf9 | 1457 | |
86fd887b | 1458 | if (!vga_default_device()) |
a75d68f6 | 1459 | vgaarb_info(dev, "setting as boot device\n"); |
86fd887b | 1460 | else if (vgadev->pdev != vga_default_device()) |
a75d68f6 | 1461 | vgaarb_info(dev, "overriding boot device\n"); |
86fd887b BP |
1462 | vga_set_default_device(vgadev->pdev); |
1463 | } | |
1464 | #endif | |
3448a19d | 1465 | if (vgadev->bridge_has_one_vga) |
a75d68f6 | 1466 | vgaarb_info(dev, "bridge control possible\n"); |
3448a19d | 1467 | else |
a75d68f6 | 1468 | vgaarb_info(dev, "no bridge control possible\n"); |
3448a19d | 1469 | } |
a75d68f6 BH |
1470 | |
1471 | pr_info("loaded\n"); | |
deb2d2ec BH |
1472 | return rc; |
1473 | } | |
1474 | subsys_initcall(vga_arb_device_init); |