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