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Commit | Line | Data |
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deb2d2ec | 1 | /* |
c0db9cbc TV |
2 | * vgaarb.c: Implements the VGA arbitration. For details refer to |
3 | * Documentation/vgaarbiter.txt | |
4 | * | |
deb2d2ec BH |
5 | * |
6 | * (C) Copyright 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org> | |
7 | * (C) Copyright 2007 Paulo R. Zanoni <przanoni@gmail.com> | |
8 | * (C) Copyright 2007, 2009 Tiago Vignatti <vignatti@freedesktop.org> | |
9 | * | |
c0db9cbc TV |
10 | * Permission is hereby granted, free of charge, to any person obtaining a |
11 | * copy of this software and associated documentation files (the "Software"), | |
12 | * to deal in the Software without restriction, including without limitation | |
13 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, | |
14 | * and/or sell copies of the Software, and to permit persons to whom the | |
15 | * Software is furnished to do so, subject to the following conditions: | |
16 | * | |
17 | * The above copyright notice and this permission notice (including the next | |
18 | * paragraph) shall be included in all copies or substantial portions of the | |
19 | * Software. | |
20 | * | |
21 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
22 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
23 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
24 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
25 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
26 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER | |
27 | * DEALINGS | |
28 | * IN THE SOFTWARE. | |
29 | * | |
deb2d2ec BH |
30 | */ |
31 | ||
8b7e2e86 TR |
32 | #define pr_fmt(fmt) "vgaarb: " fmt |
33 | ||
deb2d2ec BH |
34 | #include <linux/module.h> |
35 | #include <linux/kernel.h> | |
36 | #include <linux/pci.h> | |
37 | #include <linux/errno.h> | |
38 | #include <linux/init.h> | |
39 | #include <linux/list.h> | |
40 | #include <linux/sched.h> | |
41 | #include <linux/wait.h> | |
42 | #include <linux/spinlock.h> | |
43 | #include <linux/poll.h> | |
44 | #include <linux/miscdevice.h> | |
5a0e3ad6 | 45 | #include <linux/slab.h> |
86fd887b | 46 | #include <linux/screen_info.h> |
deb2d2ec BH |
47 | |
48 | #include <linux/uaccess.h> | |
49 | ||
50 | #include <linux/vgaarb.h> | |
51 | ||
52 | static void vga_arbiter_notify_clients(void); | |
53 | /* | |
54 | * We keep a list of all vga devices in the system to speed | |
55 | * up the various operations of the arbiter | |
56 | */ | |
57 | struct vga_device { | |
58 | struct list_head list; | |
59 | struct pci_dev *pdev; | |
60 | unsigned int decodes; /* what does it decodes */ | |
61 | unsigned int owns; /* what does it owns */ | |
62 | unsigned int locks; /* what does it locks */ | |
63 | unsigned int io_lock_cnt; /* legacy IO lock count */ | |
64 | unsigned int mem_lock_cnt; /* legacy MEM lock count */ | |
65 | unsigned int io_norm_cnt; /* normal IO count */ | |
66 | unsigned int mem_norm_cnt; /* normal MEM count */ | |
3448a19d | 67 | bool bridge_has_one_vga; |
deb2d2ec BH |
68 | /* allow IRQ enable/disable hook */ |
69 | void *cookie; | |
70 | void (*irq_set_state)(void *cookie, bool enable); | |
71 | unsigned int (*set_vga_decode)(void *cookie, bool decode); | |
72 | }; | |
73 | ||
74 | static LIST_HEAD(vga_list); | |
75 | static int vga_count, vga_decode_count; | |
76 | static bool vga_arbiter_used; | |
77 | static DEFINE_SPINLOCK(vga_lock); | |
78 | static DECLARE_WAIT_QUEUE_HEAD(vga_wait_queue); | |
79 | ||
80 | ||
81 | static const char *vga_iostate_to_str(unsigned int iostate) | |
82 | { | |
83 | /* Ignore VGA_RSRC_IO and VGA_RSRC_MEM */ | |
84 | iostate &= VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
85 | switch (iostate) { | |
86 | case VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM: | |
87 | return "io+mem"; | |
88 | case VGA_RSRC_LEGACY_IO: | |
89 | return "io"; | |
90 | case VGA_RSRC_LEGACY_MEM: | |
91 | return "mem"; | |
92 | } | |
93 | return "none"; | |
94 | } | |
95 | ||
96 | static int vga_str_to_iostate(char *buf, int str_size, int *io_state) | |
97 | { | |
98 | /* we could in theory hand out locks on IO and mem | |
99 | * separately to userspace but it can cause deadlocks */ | |
100 | if (strncmp(buf, "none", 4) == 0) { | |
101 | *io_state = VGA_RSRC_NONE; | |
102 | return 1; | |
103 | } | |
104 | ||
105 | /* XXX We're not chekcing the str_size! */ | |
106 | if (strncmp(buf, "io+mem", 6) == 0) | |
107 | goto both; | |
108 | else if (strncmp(buf, "io", 2) == 0) | |
109 | goto both; | |
110 | else if (strncmp(buf, "mem", 3) == 0) | |
111 | goto both; | |
112 | return 0; | |
113 | both: | |
114 | *io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
115 | return 1; | |
116 | } | |
117 | ||
deb2d2ec BH |
118 | /* this is only used a cookie - it should not be dereferenced */ |
119 | static struct pci_dev *vga_default; | |
deb2d2ec BH |
120 | |
121 | static void vga_arb_device_card_gone(struct pci_dev *pdev); | |
122 | ||
123 | /* Find somebody in our list */ | |
124 | static struct vga_device *vgadev_find(struct pci_dev *pdev) | |
125 | { | |
126 | struct vga_device *vgadev; | |
127 | ||
128 | list_for_each_entry(vgadev, &vga_list, list) | |
129 | if (pdev == vgadev->pdev) | |
130 | return vgadev; | |
131 | return NULL; | |
132 | } | |
133 | ||
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 | } | |
1a39b310 | 139 | |
1b23170a MG |
140 | EXPORT_SYMBOL_GPL(vga_default_device); |
141 | ||
1a39b310 MG |
142 | void vga_set_default_device(struct pci_dev *pdev) |
143 | { | |
84544a1d YL |
144 | if (vga_default == pdev) |
145 | return; | |
146 | ||
147 | pci_dev_put(vga_default); | |
148 | vga_default = pci_dev_get(pdev); | |
1a39b310 | 149 | } |
deb2d2ec BH |
150 | |
151 | static inline void vga_irq_set_state(struct vga_device *vgadev, bool state) | |
152 | { | |
153 | if (vgadev->irq_set_state) | |
154 | vgadev->irq_set_state(vgadev->cookie, state); | |
155 | } | |
156 | ||
157 | ||
158 | /* If we don't ever use VGA arb we should avoid | |
159 | turning off anything anywhere due to old X servers getting | |
160 | confused about the boot device not being VGA */ | |
161 | static void vga_check_first_use(void) | |
162 | { | |
163 | /* we should inform all GPUs in the system that | |
25985edc | 164 | * VGA arb has occurred and to try and disable resources |
deb2d2ec BH |
165 | * if they can */ |
166 | if (!vga_arbiter_used) { | |
167 | vga_arbiter_used = true; | |
168 | vga_arbiter_notify_clients(); | |
169 | } | |
170 | } | |
171 | ||
172 | static struct vga_device *__vga_tryget(struct vga_device *vgadev, | |
173 | unsigned int rsrc) | |
174 | { | |
175 | unsigned int wants, legacy_wants, match; | |
176 | struct vga_device *conflict; | |
177 | unsigned int pci_bits; | |
3448a19d DA |
178 | u32 flags = 0; |
179 | ||
deb2d2ec BH |
180 | /* Account for "normal" resources to lock. If we decode the legacy, |
181 | * counterpart, we need to request it as well | |
182 | */ | |
183 | if ((rsrc & VGA_RSRC_NORMAL_IO) && | |
184 | (vgadev->decodes & VGA_RSRC_LEGACY_IO)) | |
185 | rsrc |= VGA_RSRC_LEGACY_IO; | |
186 | if ((rsrc & VGA_RSRC_NORMAL_MEM) && | |
187 | (vgadev->decodes & VGA_RSRC_LEGACY_MEM)) | |
188 | rsrc |= VGA_RSRC_LEGACY_MEM; | |
189 | ||
2d6e9b91 TV |
190 | pr_debug("%s: %d\n", __func__, rsrc); |
191 | pr_debug("%s: owns: %d\n", __func__, vgadev->owns); | |
deb2d2ec BH |
192 | |
193 | /* Check what resources we need to acquire */ | |
194 | wants = rsrc & ~vgadev->owns; | |
195 | ||
196 | /* We already own everything, just mark locked & bye bye */ | |
197 | if (wants == 0) | |
198 | goto lock_them; | |
199 | ||
200 | /* We don't need to request a legacy resource, we just enable | |
201 | * appropriate decoding and go | |
202 | */ | |
203 | legacy_wants = wants & VGA_RSRC_LEGACY_MASK; | |
204 | if (legacy_wants == 0) | |
205 | goto enable_them; | |
206 | ||
207 | /* Ok, we don't, let's find out how we need to kick off */ | |
208 | list_for_each_entry(conflict, &vga_list, list) { | |
209 | unsigned int lwants = legacy_wants; | |
210 | unsigned int change_bridge = 0; | |
211 | ||
212 | /* Don't conflict with myself */ | |
213 | if (vgadev == conflict) | |
214 | continue; | |
215 | ||
216 | /* Check if the architecture allows a conflict between those | |
217 | * 2 devices or if they are on separate domains | |
218 | */ | |
219 | if (!vga_conflicts(vgadev->pdev, conflict->pdev)) | |
220 | continue; | |
221 | ||
222 | /* We have a possible conflict. before we go further, we must | |
223 | * check if we sit on the same bus as the conflicting device. | |
224 | * if we don't, then we must tie both IO and MEM resources | |
225 | * together since there is only a single bit controlling | |
226 | * VGA forwarding on P2P bridges | |
227 | */ | |
228 | if (vgadev->pdev->bus != conflict->pdev->bus) { | |
229 | change_bridge = 1; | |
230 | lwants = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
231 | } | |
232 | ||
233 | /* Check if the guy has a lock on the resource. If he does, | |
234 | * return the conflicting entry | |
235 | */ | |
236 | if (conflict->locks & lwants) | |
237 | return conflict; | |
238 | ||
4e4e7dc5 AW |
239 | /* Ok, now check if it owns the resource we want. We can |
240 | * lock resources that are not decoded, therefore a device | |
241 | * can own resources it doesn't decode. | |
deb2d2ec | 242 | */ |
deb2d2ec BH |
243 | match = lwants & conflict->owns; |
244 | if (!match) | |
245 | continue; | |
246 | ||
247 | /* looks like he doesn't have a lock, we can steal | |
248 | * them from him | |
249 | */ | |
deb2d2ec | 250 | |
3448a19d | 251 | flags = 0; |
deb2d2ec | 252 | pci_bits = 0; |
deb2d2ec | 253 | |
4e4e7dc5 AW |
254 | /* If we can't control legacy resources via the bridge, we |
255 | * also need to disable normal decoding. | |
256 | */ | |
3448a19d | 257 | if (!conflict->bridge_has_one_vga) { |
4e4e7dc5 | 258 | if ((match & conflict->decodes) & VGA_RSRC_LEGACY_MEM) |
3448a19d | 259 | pci_bits |= PCI_COMMAND_MEMORY; |
4e4e7dc5 | 260 | if ((match & conflict->decodes) & VGA_RSRC_LEGACY_IO) |
3448a19d | 261 | pci_bits |= PCI_COMMAND_IO; |
4e4e7dc5 AW |
262 | |
263 | if (pci_bits) { | |
264 | vga_irq_set_state(conflict, false); | |
265 | flags |= PCI_VGA_STATE_CHANGE_DECODES; | |
266 | } | |
3448a19d DA |
267 | } |
268 | ||
269 | if (change_bridge) | |
270 | flags |= PCI_VGA_STATE_CHANGE_BRIDGE; | |
271 | ||
272 | pci_set_vga_state(conflict->pdev, false, pci_bits, flags); | |
f22d776f | 273 | conflict->owns &= ~match; |
4e4e7dc5 AW |
274 | |
275 | /* If we disabled normal decoding, reflect it in owns */ | |
276 | if (pci_bits & PCI_COMMAND_MEMORY) | |
deb2d2ec | 277 | conflict->owns &= ~VGA_RSRC_NORMAL_MEM; |
4e4e7dc5 | 278 | if (pci_bits & PCI_COMMAND_IO) |
deb2d2ec BH |
279 | conflict->owns &= ~VGA_RSRC_NORMAL_IO; |
280 | } | |
281 | ||
282 | enable_them: | |
283 | /* ok dude, we got it, everybody conflicting has been disabled, let's | |
4e4e7dc5 AW |
284 | * enable us. Mark any bits in "owns" regardless of whether we |
285 | * decoded them. We can lock resources we don't decode, therefore | |
286 | * we must track them via "owns". | |
deb2d2ec | 287 | */ |
3448a19d | 288 | flags = 0; |
deb2d2ec | 289 | pci_bits = 0; |
deb2d2ec | 290 | |
3448a19d DA |
291 | if (!vgadev->bridge_has_one_vga) { |
292 | flags |= PCI_VGA_STATE_CHANGE_DECODES; | |
293 | if (wants & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) | |
294 | pci_bits |= PCI_COMMAND_MEMORY; | |
295 | if (wants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) | |
296 | pci_bits |= PCI_COMMAND_IO; | |
297 | } | |
4e4e7dc5 | 298 | if (wants & VGA_RSRC_LEGACY_MASK) |
3448a19d DA |
299 | flags |= PCI_VGA_STATE_CHANGE_BRIDGE; |
300 | ||
301 | pci_set_vga_state(vgadev->pdev, true, pci_bits, flags); | |
302 | ||
303 | if (!vgadev->bridge_has_one_vga) { | |
304 | vga_irq_set_state(vgadev, true); | |
305 | } | |
4e4e7dc5 | 306 | vgadev->owns |= wants; |
deb2d2ec BH |
307 | lock_them: |
308 | vgadev->locks |= (rsrc & VGA_RSRC_LEGACY_MASK); | |
309 | if (rsrc & VGA_RSRC_LEGACY_IO) | |
310 | vgadev->io_lock_cnt++; | |
311 | if (rsrc & VGA_RSRC_LEGACY_MEM) | |
312 | vgadev->mem_lock_cnt++; | |
313 | if (rsrc & VGA_RSRC_NORMAL_IO) | |
314 | vgadev->io_norm_cnt++; | |
315 | if (rsrc & VGA_RSRC_NORMAL_MEM) | |
316 | vgadev->mem_norm_cnt++; | |
317 | ||
318 | return NULL; | |
319 | } | |
320 | ||
321 | static void __vga_put(struct vga_device *vgadev, unsigned int rsrc) | |
322 | { | |
323 | unsigned int old_locks = vgadev->locks; | |
324 | ||
2d6e9b91 | 325 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
326 | |
327 | /* Update our counters, and account for equivalent legacy resources | |
328 | * if we decode them | |
329 | */ | |
330 | if ((rsrc & VGA_RSRC_NORMAL_IO) && vgadev->io_norm_cnt > 0) { | |
331 | vgadev->io_norm_cnt--; | |
332 | if (vgadev->decodes & VGA_RSRC_LEGACY_IO) | |
333 | rsrc |= VGA_RSRC_LEGACY_IO; | |
334 | } | |
335 | if ((rsrc & VGA_RSRC_NORMAL_MEM) && vgadev->mem_norm_cnt > 0) { | |
336 | vgadev->mem_norm_cnt--; | |
337 | if (vgadev->decodes & VGA_RSRC_LEGACY_MEM) | |
338 | rsrc |= VGA_RSRC_LEGACY_MEM; | |
339 | } | |
340 | if ((rsrc & VGA_RSRC_LEGACY_IO) && vgadev->io_lock_cnt > 0) | |
341 | vgadev->io_lock_cnt--; | |
342 | if ((rsrc & VGA_RSRC_LEGACY_MEM) && vgadev->mem_lock_cnt > 0) | |
343 | vgadev->mem_lock_cnt--; | |
344 | ||
345 | /* Just clear lock bits, we do lazy operations so we don't really | |
346 | * have to bother about anything else at this point | |
347 | */ | |
348 | if (vgadev->io_lock_cnt == 0) | |
349 | vgadev->locks &= ~VGA_RSRC_LEGACY_IO; | |
350 | if (vgadev->mem_lock_cnt == 0) | |
351 | vgadev->locks &= ~VGA_RSRC_LEGACY_MEM; | |
352 | ||
353 | /* Kick the wait queue in case somebody was waiting if we actually | |
354 | * released something | |
355 | */ | |
356 | if (old_locks != vgadev->locks) | |
357 | wake_up_all(&vga_wait_queue); | |
358 | } | |
359 | ||
360 | int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible) | |
361 | { | |
362 | struct vga_device *vgadev, *conflict; | |
363 | unsigned long flags; | |
364 | wait_queue_t wait; | |
365 | int rc = 0; | |
366 | ||
367 | vga_check_first_use(); | |
368 | /* The one who calls us should check for this, but lets be sure... */ | |
369 | if (pdev == NULL) | |
370 | pdev = vga_default_device(); | |
371 | if (pdev == NULL) | |
372 | return 0; | |
373 | ||
374 | for (;;) { | |
375 | spin_lock_irqsave(&vga_lock, flags); | |
376 | vgadev = vgadev_find(pdev); | |
377 | if (vgadev == NULL) { | |
378 | spin_unlock_irqrestore(&vga_lock, flags); | |
379 | rc = -ENODEV; | |
380 | break; | |
381 | } | |
382 | conflict = __vga_tryget(vgadev, rsrc); | |
383 | spin_unlock_irqrestore(&vga_lock, flags); | |
384 | if (conflict == NULL) | |
385 | break; | |
386 | ||
387 | ||
388 | /* We have a conflict, we wait until somebody kicks the | |
389 | * work queue. Currently we have one work queue that we | |
390 | * kick each time some resources are released, but it would | |
391 | * be fairly easy to have a per device one so that we only | |
392 | * need to attach to the conflicting device | |
393 | */ | |
394 | init_waitqueue_entry(&wait, current); | |
395 | add_wait_queue(&vga_wait_queue, &wait); | |
396 | set_current_state(interruptible ? | |
397 | TASK_INTERRUPTIBLE : | |
398 | TASK_UNINTERRUPTIBLE); | |
399 | if (signal_pending(current)) { | |
400 | rc = -EINTR; | |
401 | break; | |
402 | } | |
403 | schedule(); | |
404 | remove_wait_queue(&vga_wait_queue, &wait); | |
deb2d2ec BH |
405 | } |
406 | return rc; | |
407 | } | |
408 | EXPORT_SYMBOL(vga_get); | |
409 | ||
410 | int vga_tryget(struct pci_dev *pdev, unsigned int rsrc) | |
411 | { | |
412 | struct vga_device *vgadev; | |
413 | unsigned long flags; | |
414 | int rc = 0; | |
415 | ||
416 | vga_check_first_use(); | |
417 | ||
418 | /* The one who calls us should check for this, but lets be sure... */ | |
419 | if (pdev == NULL) | |
420 | pdev = vga_default_device(); | |
421 | if (pdev == NULL) | |
422 | return 0; | |
423 | spin_lock_irqsave(&vga_lock, flags); | |
424 | vgadev = vgadev_find(pdev); | |
425 | if (vgadev == NULL) { | |
426 | rc = -ENODEV; | |
427 | goto bail; | |
428 | } | |
429 | if (__vga_tryget(vgadev, rsrc)) | |
430 | rc = -EBUSY; | |
431 | bail: | |
432 | spin_unlock_irqrestore(&vga_lock, flags); | |
433 | return rc; | |
434 | } | |
435 | EXPORT_SYMBOL(vga_tryget); | |
436 | ||
437 | void vga_put(struct pci_dev *pdev, unsigned int rsrc) | |
438 | { | |
439 | struct vga_device *vgadev; | |
440 | unsigned long flags; | |
441 | ||
442 | /* The one who calls us should check for this, but lets be sure... */ | |
443 | if (pdev == NULL) | |
444 | pdev = vga_default_device(); | |
445 | if (pdev == NULL) | |
446 | return; | |
447 | spin_lock_irqsave(&vga_lock, flags); | |
448 | vgadev = vgadev_find(pdev); | |
449 | if (vgadev == NULL) | |
450 | goto bail; | |
451 | __vga_put(vgadev, rsrc); | |
452 | bail: | |
453 | spin_unlock_irqrestore(&vga_lock, flags); | |
454 | } | |
455 | EXPORT_SYMBOL(vga_put); | |
456 | ||
3448a19d DA |
457 | /* Rules for using a bridge to control a VGA descendant decoding: |
458 | if a bridge has only one VGA descendant then it can be used | |
459 | to control the VGA routing for that device. | |
460 | It should always use the bridge closest to the device to control it. | |
461 | If a bridge has a direct VGA descendant, but also have a sub-bridge | |
462 | VGA descendant then we cannot use that bridge to control the direct VGA descendant. | |
463 | So for every device we register, we need to iterate all its parent bridges | |
464 | so we can invalidate any devices using them properly. | |
465 | */ | |
466 | static void vga_arbiter_check_bridge_sharing(struct vga_device *vgadev) | |
467 | { | |
468 | struct vga_device *same_bridge_vgadev; | |
469 | struct pci_bus *new_bus, *bus; | |
470 | struct pci_dev *new_bridge, *bridge; | |
471 | ||
472 | vgadev->bridge_has_one_vga = true; | |
473 | ||
474 | if (list_empty(&vga_list)) | |
475 | return; | |
476 | ||
477 | /* okay iterate the new devices bridge hierarachy */ | |
478 | new_bus = vgadev->pdev->bus; | |
479 | while (new_bus) { | |
480 | new_bridge = new_bus->self; | |
481 | ||
f6252114 DA |
482 | /* go through list of devices already registered */ |
483 | list_for_each_entry(same_bridge_vgadev, &vga_list, list) { | |
484 | bus = same_bridge_vgadev->pdev->bus; | |
485 | bridge = bus->self; | |
486 | ||
487 | /* see if the share a bridge with this device */ | |
488 | if (new_bridge == bridge) { | |
489 | /* if their direct parent bridge is the same | |
490 | as any bridge of this device then it can't be used | |
491 | for that device */ | |
492 | same_bridge_vgadev->bridge_has_one_vga = false; | |
493 | } | |
3448a19d | 494 | |
f6252114 DA |
495 | /* now iterate the previous devices bridge hierarchy */ |
496 | /* if the new devices parent bridge is in the other devices | |
497 | hierarchy then we can't use it to control this device */ | |
498 | while (bus) { | |
499 | bridge = bus->self; | |
500 | if (bridge) { | |
501 | if (bridge == vgadev->pdev->bus->self) | |
502 | vgadev->bridge_has_one_vga = false; | |
3448a19d | 503 | } |
f6252114 | 504 | bus = bus->parent; |
3448a19d DA |
505 | } |
506 | } | |
507 | new_bus = new_bus->parent; | |
508 | } | |
509 | } | |
510 | ||
deb2d2ec BH |
511 | /* |
512 | * Currently, we assume that the "initial" setup of the system is | |
513 | * not sane, that is we come up with conflicting devices and let | |
514 | * the arbiter's client decides if devices decodes or not legacy | |
515 | * things. | |
516 | */ | |
517 | static bool vga_arbiter_add_pci_device(struct pci_dev *pdev) | |
518 | { | |
519 | struct vga_device *vgadev; | |
520 | unsigned long flags; | |
521 | struct pci_bus *bus; | |
522 | struct pci_dev *bridge; | |
523 | u16 cmd; | |
524 | ||
525 | /* Only deal with VGA class devices */ | |
526 | if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA) | |
527 | return false; | |
528 | ||
529 | /* Allocate structure */ | |
530 | vgadev = kmalloc(sizeof(struct vga_device), GFP_KERNEL); | |
531 | if (vgadev == NULL) { | |
8b7e2e86 | 532 | pr_err("failed to allocate pci device\n"); |
deb2d2ec BH |
533 | /* What to do on allocation failure ? For now, let's |
534 | * just do nothing, I'm not sure there is anything saner | |
535 | * to be done | |
536 | */ | |
537 | return false; | |
538 | } | |
539 | ||
540 | memset(vgadev, 0, sizeof(*vgadev)); | |
541 | ||
542 | /* Take lock & check for duplicates */ | |
543 | spin_lock_irqsave(&vga_lock, flags); | |
544 | if (vgadev_find(pdev) != NULL) { | |
545 | BUG_ON(1); | |
546 | goto fail; | |
547 | } | |
548 | vgadev->pdev = pdev; | |
549 | ||
550 | /* By default, assume we decode everything */ | |
551 | vgadev->decodes = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM | | |
552 | VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM; | |
553 | ||
554 | /* by default mark it as decoding */ | |
555 | vga_decode_count++; | |
556 | /* Mark that we "own" resources based on our enables, we will | |
557 | * clear that below if the bridge isn't forwarding | |
558 | */ | |
559 | pci_read_config_word(pdev, PCI_COMMAND, &cmd); | |
560 | if (cmd & PCI_COMMAND_IO) | |
561 | vgadev->owns |= VGA_RSRC_LEGACY_IO; | |
562 | if (cmd & PCI_COMMAND_MEMORY) | |
563 | vgadev->owns |= VGA_RSRC_LEGACY_MEM; | |
564 | ||
565 | /* Check if VGA cycles can get down to us */ | |
566 | bus = pdev->bus; | |
567 | while (bus) { | |
568 | bridge = bus->self; | |
569 | if (bridge) { | |
570 | u16 l; | |
571 | pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, | |
572 | &l); | |
573 | if (!(l & PCI_BRIDGE_CTL_VGA)) { | |
574 | vgadev->owns = 0; | |
575 | break; | |
576 | } | |
577 | } | |
578 | bus = bus->parent; | |
579 | } | |
580 | ||
581 | /* Deal with VGA default device. Use first enabled one | |
582 | * by default if arch doesn't have it's own hook | |
583 | */ | |
deb2d2ec | 584 | if (vga_default == NULL && |
86fd887b | 585 | ((vgadev->owns & VGA_RSRC_LEGACY_MASK) == VGA_RSRC_LEGACY_MASK)) { |
8b7e2e86 | 586 | pr_info("setting as boot device: PCI:%s\n", pci_name(pdev)); |
84544a1d | 587 | vga_set_default_device(pdev); |
86fd887b | 588 | } |
deb2d2ec | 589 | |
3448a19d DA |
590 | vga_arbiter_check_bridge_sharing(vgadev); |
591 | ||
deb2d2ec BH |
592 | /* Add to the list */ |
593 | list_add(&vgadev->list, &vga_list); | |
594 | vga_count++; | |
8b7e2e86 | 595 | pr_info("device added: PCI:%s,decodes=%s,owns=%s,locks=%s\n", |
deb2d2ec BH |
596 | pci_name(pdev), |
597 | vga_iostate_to_str(vgadev->decodes), | |
598 | vga_iostate_to_str(vgadev->owns), | |
599 | vga_iostate_to_str(vgadev->locks)); | |
600 | ||
601 | spin_unlock_irqrestore(&vga_lock, flags); | |
602 | return true; | |
603 | fail: | |
604 | spin_unlock_irqrestore(&vga_lock, flags); | |
605 | kfree(vgadev); | |
606 | return false; | |
607 | } | |
608 | ||
609 | static bool vga_arbiter_del_pci_device(struct pci_dev *pdev) | |
610 | { | |
611 | struct vga_device *vgadev; | |
612 | unsigned long flags; | |
613 | bool ret = true; | |
614 | ||
615 | spin_lock_irqsave(&vga_lock, flags); | |
616 | vgadev = vgadev_find(pdev); | |
617 | if (vgadev == NULL) { | |
618 | ret = false; | |
619 | goto bail; | |
620 | } | |
621 | ||
84544a1d YL |
622 | if (vga_default == pdev) |
623 | vga_set_default_device(NULL); | |
deb2d2ec BH |
624 | |
625 | if (vgadev->decodes & (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)) | |
626 | vga_decode_count--; | |
627 | ||
628 | /* Remove entry from list */ | |
629 | list_del(&vgadev->list); | |
630 | vga_count--; | |
631 | /* Notify userland driver that the device is gone so it discards | |
632 | * it's copies of the pci_dev pointer | |
633 | */ | |
634 | vga_arb_device_card_gone(pdev); | |
635 | ||
636 | /* Wake up all possible waiters */ | |
637 | wake_up_all(&vga_wait_queue); | |
638 | bail: | |
639 | spin_unlock_irqrestore(&vga_lock, flags); | |
640 | kfree(vgadev); | |
641 | return ret; | |
642 | } | |
643 | ||
644 | /* this is called with the lock */ | |
645 | static inline void vga_update_device_decodes(struct vga_device *vgadev, | |
646 | int new_decodes) | |
647 | { | |
5c0f6ee7 | 648 | int old_decodes, decodes_removed, decodes_unlocked; |
deb2d2ec BH |
649 | |
650 | old_decodes = vgadev->decodes; | |
5c0f6ee7 AW |
651 | decodes_removed = ~new_decodes & old_decodes; |
652 | decodes_unlocked = vgadev->locks & decodes_removed; | |
deb2d2ec BH |
653 | vgadev->decodes = new_decodes; |
654 | ||
8b7e2e86 | 655 | pr_info("device changed decodes: PCI:%s,olddecodes=%s,decodes=%s:owns=%s\n", |
deb2d2ec BH |
656 | pci_name(vgadev->pdev), |
657 | vga_iostate_to_str(old_decodes), | |
658 | vga_iostate_to_str(vgadev->decodes), | |
659 | vga_iostate_to_str(vgadev->owns)); | |
660 | ||
5c0f6ee7 AW |
661 | /* if we removed locked decodes, lock count goes to zero, and release */ |
662 | if (decodes_unlocked) { | |
663 | if (decodes_unlocked & VGA_RSRC_LEGACY_IO) | |
664 | vgadev->io_lock_cnt = 0; | |
665 | if (decodes_unlocked & VGA_RSRC_LEGACY_MEM) | |
666 | vgadev->mem_lock_cnt = 0; | |
667 | __vga_put(vgadev, decodes_unlocked); | |
deb2d2ec BH |
668 | } |
669 | ||
670 | /* change decodes counter */ | |
5c0f6ee7 AW |
671 | if (old_decodes & VGA_RSRC_LEGACY_MASK && |
672 | !(new_decodes & VGA_RSRC_LEGACY_MASK)) | |
673 | vga_decode_count--; | |
674 | if (!(old_decodes & VGA_RSRC_LEGACY_MASK) && | |
675 | new_decodes & VGA_RSRC_LEGACY_MASK) | |
676 | vga_decode_count++; | |
8b7e2e86 | 677 | pr_debug("decoding count now is: %d\n", vga_decode_count); |
deb2d2ec BH |
678 | } |
679 | ||
201ba4c4 | 680 | static void __vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes, bool userspace) |
deb2d2ec BH |
681 | { |
682 | struct vga_device *vgadev; | |
683 | unsigned long flags; | |
684 | ||
685 | decodes &= VGA_RSRC_LEGACY_MASK; | |
686 | ||
687 | spin_lock_irqsave(&vga_lock, flags); | |
688 | vgadev = vgadev_find(pdev); | |
689 | if (vgadev == NULL) | |
690 | goto bail; | |
691 | ||
692 | /* don't let userspace futz with kernel driver decodes */ | |
693 | if (userspace && vgadev->set_vga_decode) | |
694 | goto bail; | |
695 | ||
696 | /* update the device decodes + counter */ | |
697 | vga_update_device_decodes(vgadev, decodes); | |
698 | ||
699 | /* XXX if somebody is going from "doesn't decode" to "decodes" state | |
700 | * here, additional care must be taken as we may have pending owner | |
701 | * ship of non-legacy region ... | |
702 | */ | |
703 | bail: | |
704 | spin_unlock_irqrestore(&vga_lock, flags); | |
705 | } | |
706 | ||
707 | void vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes) | |
708 | { | |
709 | __vga_set_legacy_decoding(pdev, decodes, false); | |
710 | } | |
711 | EXPORT_SYMBOL(vga_set_legacy_decoding); | |
712 | ||
deb2d2ec BH |
713 | /* call with NULL to unregister */ |
714 | int vga_client_register(struct pci_dev *pdev, void *cookie, | |
715 | void (*irq_set_state)(void *cookie, bool state), | |
716 | unsigned int (*set_vga_decode)(void *cookie, bool decode)) | |
717 | { | |
934f992c | 718 | int ret = -ENODEV; |
deb2d2ec BH |
719 | struct vga_device *vgadev; |
720 | unsigned long flags; | |
721 | ||
722 | spin_lock_irqsave(&vga_lock, flags); | |
723 | vgadev = vgadev_find(pdev); | |
724 | if (!vgadev) | |
725 | goto bail; | |
726 | ||
727 | vgadev->irq_set_state = irq_set_state; | |
728 | vgadev->set_vga_decode = set_vga_decode; | |
729 | vgadev->cookie = cookie; | |
730 | ret = 0; | |
731 | ||
732 | bail: | |
733 | spin_unlock_irqrestore(&vga_lock, flags); | |
734 | return ret; | |
735 | ||
736 | } | |
737 | EXPORT_SYMBOL(vga_client_register); | |
738 | ||
739 | /* | |
740 | * Char driver implementation | |
741 | * | |
742 | * Semantics is: | |
743 | * | |
744 | * open : open user instance of the arbitrer. by default, it's | |
745 | * attached to the default VGA device of the system. | |
746 | * | |
747 | * close : close user instance, release locks | |
748 | * | |
749 | * read : return a string indicating the status of the target. | |
750 | * an IO state string is of the form {io,mem,io+mem,none}, | |
751 | * mc and ic are respectively mem and io lock counts (for | |
752 | * debugging/diagnostic only). "decodes" indicate what the | |
753 | * card currently decodes, "owns" indicates what is currently | |
754 | * enabled on it, and "locks" indicates what is locked by this | |
755 | * card. If the card is unplugged, we get "invalid" then for | |
756 | * card_ID and an -ENODEV error is returned for any command | |
757 | * until a new card is targeted | |
758 | * | |
759 | * "<card_ID>,decodes=<io_state>,owns=<io_state>,locks=<io_state> (ic,mc)" | |
760 | * | |
761 | * write : write a command to the arbiter. List of commands is: | |
762 | * | |
763 | * target <card_ID> : switch target to card <card_ID> (see below) | |
764 | * lock <io_state> : acquires locks on target ("none" is invalid io_state) | |
765 | * trylock <io_state> : non-blocking acquire locks on target | |
766 | * unlock <io_state> : release locks on target | |
767 | * unlock all : release all locks on target held by this user | |
768 | * decodes <io_state> : set the legacy decoding attributes for the card | |
769 | * | |
770 | * poll : event if something change on any card (not just the target) | |
771 | * | |
772 | * card_ID is of the form "PCI:domain:bus:dev.fn". It can be set to "default" | |
773 | * to go back to the system default card (TODO: not implemented yet). | |
774 | * Currently, only PCI is supported as a prefix, but the userland API may | |
775 | * support other bus types in the future, even if the current kernel | |
776 | * implementation doesn't. | |
777 | * | |
778 | * Note about locks: | |
779 | * | |
780 | * The driver keeps track of which user has what locks on which card. It | |
781 | * supports stacking, like the kernel one. This complexifies the implementation | |
782 | * a bit, but makes the arbiter more tolerant to userspace problems and able | |
783 | * to properly cleanup in all cases when a process dies. | |
784 | * Currently, a max of 16 cards simultaneously can have locks issued from | |
785 | * userspace for a given user (file descriptor instance) of the arbiter. | |
786 | * | |
787 | * If the device is hot-unplugged, there is a hook inside the module to notify | |
788 | * they being added/removed in the system and automatically added/removed in | |
789 | * the arbiter. | |
790 | */ | |
791 | ||
36028f33 | 792 | #define MAX_USER_CARDS CONFIG_VGA_ARB_MAX_GPUS |
deb2d2ec BH |
793 | #define PCI_INVALID_CARD ((struct pci_dev *)-1UL) |
794 | ||
795 | /* | |
796 | * Each user has an array of these, tracking which cards have locks | |
797 | */ | |
798 | struct vga_arb_user_card { | |
799 | struct pci_dev *pdev; | |
800 | unsigned int mem_cnt; | |
801 | unsigned int io_cnt; | |
802 | }; | |
803 | ||
804 | struct vga_arb_private { | |
805 | struct list_head list; | |
806 | struct pci_dev *target; | |
807 | struct vga_arb_user_card cards[MAX_USER_CARDS]; | |
808 | spinlock_t lock; | |
809 | }; | |
810 | ||
811 | static LIST_HEAD(vga_user_list); | |
812 | static DEFINE_SPINLOCK(vga_user_lock); | |
813 | ||
814 | ||
815 | /* | |
816 | * This function gets a string in the format: "PCI:domain:bus:dev.fn" and | |
817 | * returns the respective values. If the string is not in this format, | |
818 | * it returns 0. | |
819 | */ | |
820 | static int vga_pci_str_to_vars(char *buf, int count, unsigned int *domain, | |
821 | unsigned int *bus, unsigned int *devfn) | |
822 | { | |
823 | int n; | |
824 | unsigned int slot, func; | |
825 | ||
826 | ||
827 | n = sscanf(buf, "PCI:%x:%x:%x.%x", domain, bus, &slot, &func); | |
828 | if (n != 4) | |
829 | return 0; | |
830 | ||
831 | *devfn = PCI_DEVFN(slot, func); | |
832 | ||
833 | return 1; | |
834 | } | |
835 | ||
836 | static ssize_t vga_arb_read(struct file *file, char __user * buf, | |
837 | size_t count, loff_t *ppos) | |
838 | { | |
839 | struct vga_arb_private *priv = file->private_data; | |
840 | struct vga_device *vgadev; | |
841 | struct pci_dev *pdev; | |
842 | unsigned long flags; | |
843 | size_t len; | |
844 | int rc; | |
845 | char *lbuf; | |
846 | ||
847 | lbuf = kmalloc(1024, GFP_KERNEL); | |
848 | if (lbuf == NULL) | |
849 | return -ENOMEM; | |
850 | ||
851 | /* Shields against vga_arb_device_card_gone (pci_dev going | |
852 | * away), and allows access to vga list | |
853 | */ | |
854 | spin_lock_irqsave(&vga_lock, flags); | |
855 | ||
25985edc | 856 | /* If we are targeting the default, use it */ |
deb2d2ec BH |
857 | pdev = priv->target; |
858 | if (pdev == NULL || pdev == PCI_INVALID_CARD) { | |
859 | spin_unlock_irqrestore(&vga_lock, flags); | |
860 | len = sprintf(lbuf, "invalid"); | |
861 | goto done; | |
862 | } | |
863 | ||
864 | /* Find card vgadev structure */ | |
865 | vgadev = vgadev_find(pdev); | |
866 | if (vgadev == NULL) { | |
867 | /* Wow, it's not in the list, that shouldn't happen, | |
868 | * let's fix us up and return invalid card | |
869 | */ | |
870 | if (pdev == priv->target) | |
871 | vga_arb_device_card_gone(pdev); | |
872 | spin_unlock_irqrestore(&vga_lock, flags); | |
873 | len = sprintf(lbuf, "invalid"); | |
874 | goto done; | |
875 | } | |
876 | ||
877 | /* Fill the buffer with infos */ | |
878 | len = snprintf(lbuf, 1024, | |
879 | "count:%d,PCI:%s,decodes=%s,owns=%s,locks=%s(%d:%d)\n", | |
880 | vga_decode_count, pci_name(pdev), | |
881 | vga_iostate_to_str(vgadev->decodes), | |
882 | vga_iostate_to_str(vgadev->owns), | |
883 | vga_iostate_to_str(vgadev->locks), | |
884 | vgadev->io_lock_cnt, vgadev->mem_lock_cnt); | |
885 | ||
886 | spin_unlock_irqrestore(&vga_lock, flags); | |
887 | done: | |
888 | ||
889 | /* Copy that to user */ | |
890 | if (len > count) | |
891 | len = count; | |
892 | rc = copy_to_user(buf, lbuf, len); | |
893 | kfree(lbuf); | |
894 | if (rc) | |
895 | return -EFAULT; | |
896 | return len; | |
897 | } | |
898 | ||
899 | /* | |
900 | * TODO: To avoid parsing inside kernel and to improve the speed we may | |
901 | * consider use ioctl here | |
902 | */ | |
903 | static ssize_t vga_arb_write(struct file *file, const char __user * buf, | |
904 | size_t count, loff_t *ppos) | |
905 | { | |
906 | struct vga_arb_private *priv = file->private_data; | |
907 | struct vga_arb_user_card *uc = NULL; | |
908 | struct pci_dev *pdev; | |
909 | ||
910 | unsigned int io_state; | |
911 | ||
912 | char *kbuf, *curr_pos; | |
913 | size_t remaining = count; | |
914 | ||
915 | int ret_val; | |
916 | int i; | |
917 | ||
918 | ||
919 | kbuf = kmalloc(count + 1, GFP_KERNEL); | |
920 | if (!kbuf) | |
921 | return -ENOMEM; | |
922 | ||
923 | if (copy_from_user(kbuf, buf, count)) { | |
924 | kfree(kbuf); | |
925 | return -EFAULT; | |
926 | } | |
927 | curr_pos = kbuf; | |
928 | kbuf[count] = '\0'; /* Just to make sure... */ | |
929 | ||
930 | if (strncmp(curr_pos, "lock ", 5) == 0) { | |
931 | curr_pos += 5; | |
932 | remaining -= 5; | |
933 | ||
2d6e9b91 | 934 | pr_debug("client 0x%p called 'lock'\n", priv); |
deb2d2ec BH |
935 | |
936 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
937 | ret_val = -EPROTO; | |
938 | goto done; | |
939 | } | |
940 | if (io_state == VGA_RSRC_NONE) { | |
941 | ret_val = -EPROTO; | |
942 | goto done; | |
943 | } | |
944 | ||
945 | pdev = priv->target; | |
946 | if (priv->target == NULL) { | |
947 | ret_val = -ENODEV; | |
948 | goto done; | |
949 | } | |
950 | ||
951 | vga_get_uninterruptible(pdev, io_state); | |
952 | ||
953 | /* Update the client's locks lists... */ | |
954 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
955 | if (priv->cards[i].pdev == pdev) { | |
956 | if (io_state & VGA_RSRC_LEGACY_IO) | |
957 | priv->cards[i].io_cnt++; | |
958 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
959 | priv->cards[i].mem_cnt++; | |
960 | break; | |
961 | } | |
962 | } | |
963 | ||
964 | ret_val = count; | |
965 | goto done; | |
966 | } else if (strncmp(curr_pos, "unlock ", 7) == 0) { | |
967 | curr_pos += 7; | |
968 | remaining -= 7; | |
969 | ||
2d6e9b91 | 970 | pr_debug("client 0x%p called 'unlock'\n", priv); |
deb2d2ec BH |
971 | |
972 | if (strncmp(curr_pos, "all", 3) == 0) | |
973 | io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
974 | else { | |
975 | if (!vga_str_to_iostate | |
976 | (curr_pos, remaining, &io_state)) { | |
977 | ret_val = -EPROTO; | |
978 | goto done; | |
979 | } | |
980 | /* TODO: Add this? | |
981 | if (io_state == VGA_RSRC_NONE) { | |
982 | ret_val = -EPROTO; | |
983 | goto done; | |
984 | } | |
985 | */ | |
986 | } | |
987 | ||
988 | pdev = priv->target; | |
989 | if (priv->target == NULL) { | |
990 | ret_val = -ENODEV; | |
991 | goto done; | |
992 | } | |
993 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
994 | if (priv->cards[i].pdev == pdev) | |
995 | uc = &priv->cards[i]; | |
996 | } | |
997 | ||
c916874d JL |
998 | if (!uc) { |
999 | ret_val = -EINVAL; | |
1000 | goto done; | |
1001 | } | |
deb2d2ec | 1002 | |
c916874d JL |
1003 | if (io_state & VGA_RSRC_LEGACY_IO && uc->io_cnt == 0) { |
1004 | ret_val = -EINVAL; | |
1005 | goto done; | |
1006 | } | |
deb2d2ec | 1007 | |
c916874d JL |
1008 | if (io_state & VGA_RSRC_LEGACY_MEM && uc->mem_cnt == 0) { |
1009 | ret_val = -EINVAL; | |
1010 | goto done; | |
1011 | } | |
deb2d2ec BH |
1012 | |
1013 | vga_put(pdev, io_state); | |
1014 | ||
1015 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1016 | uc->io_cnt--; | |
1017 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1018 | uc->mem_cnt--; | |
1019 | ||
1020 | ret_val = count; | |
1021 | goto done; | |
1022 | } else if (strncmp(curr_pos, "trylock ", 8) == 0) { | |
1023 | curr_pos += 8; | |
1024 | remaining -= 8; | |
1025 | ||
2d6e9b91 | 1026 | pr_debug("client 0x%p called 'trylock'\n", priv); |
deb2d2ec BH |
1027 | |
1028 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1029 | ret_val = -EPROTO; | |
1030 | goto done; | |
1031 | } | |
1032 | /* TODO: Add this? | |
1033 | if (io_state == VGA_RSRC_NONE) { | |
1034 | ret_val = -EPROTO; | |
1035 | goto done; | |
1036 | } | |
1037 | */ | |
1038 | ||
1039 | pdev = priv->target; | |
1040 | if (priv->target == NULL) { | |
1041 | ret_val = -ENODEV; | |
1042 | goto done; | |
1043 | } | |
1044 | ||
1045 | if (vga_tryget(pdev, io_state)) { | |
1046 | /* Update the client's locks lists... */ | |
1047 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1048 | if (priv->cards[i].pdev == pdev) { | |
1049 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1050 | priv->cards[i].io_cnt++; | |
1051 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1052 | priv->cards[i].mem_cnt++; | |
1053 | break; | |
1054 | } | |
1055 | } | |
1056 | ret_val = count; | |
1057 | goto done; | |
1058 | } else { | |
1059 | ret_val = -EBUSY; | |
1060 | goto done; | |
1061 | } | |
1062 | ||
1063 | } else if (strncmp(curr_pos, "target ", 7) == 0) { | |
1064 | unsigned int domain, bus, devfn; | |
1065 | struct vga_device *vgadev; | |
1066 | ||
1067 | curr_pos += 7; | |
1068 | remaining -= 7; | |
2d6e9b91 | 1069 | pr_debug("client 0x%p called 'target'\n", priv); |
deb2d2ec | 1070 | /* if target is default */ |
2cc9116c | 1071 | if (!strncmp(curr_pos, "default", 7)) |
deb2d2ec BH |
1072 | pdev = pci_dev_get(vga_default_device()); |
1073 | else { | |
1074 | if (!vga_pci_str_to_vars(curr_pos, remaining, | |
1075 | &domain, &bus, &devfn)) { | |
1076 | ret_val = -EPROTO; | |
1077 | goto done; | |
1078 | } | |
8b7e2e86 | 1079 | pr_debug("%s ==> %x:%x:%x.%x\n", curr_pos, |
773a38db MT |
1080 | domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn)); |
1081 | ||
f85567c8 | 1082 | pdev = pci_get_domain_bus_and_slot(domain, bus, devfn); |
8b7e2e86 | 1083 | pr_debug("pdev %p\n", pdev); |
deb2d2ec | 1084 | if (!pdev) { |
8b7e2e86 | 1085 | pr_err("invalid PCI address %x:%x:%x\n", |
f85567c8 | 1086 | domain, bus, devfn); |
deb2d2ec BH |
1087 | ret_val = -ENODEV; |
1088 | goto done; | |
1089 | } | |
1090 | } | |
1091 | ||
1092 | vgadev = vgadev_find(pdev); | |
8b7e2e86 | 1093 | pr_debug("vgadev %p\n", vgadev); |
deb2d2ec | 1094 | if (vgadev == NULL) { |
eb6944f2 | 1095 | if (pdev) { |
8b7e2e86 | 1096 | pr_err("this pci device is not a vga device\n"); |
eb6944f2 TR |
1097 | pci_dev_put(pdev); |
1098 | } | |
1099 | ||
deb2d2ec BH |
1100 | ret_val = -ENODEV; |
1101 | goto done; | |
1102 | } | |
1103 | ||
1104 | priv->target = pdev; | |
1105 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1106 | if (priv->cards[i].pdev == pdev) | |
1107 | break; | |
1108 | if (priv->cards[i].pdev == NULL) { | |
1109 | priv->cards[i].pdev = pdev; | |
1110 | priv->cards[i].io_cnt = 0; | |
1111 | priv->cards[i].mem_cnt = 0; | |
1112 | break; | |
1113 | } | |
1114 | } | |
1115 | if (i == MAX_USER_CARDS) { | |
8b7e2e86 | 1116 | pr_err("maximum user cards (%d) number reached!\n", |
773a38db | 1117 | MAX_USER_CARDS); |
deb2d2ec BH |
1118 | pci_dev_put(pdev); |
1119 | /* XXX: which value to return? */ | |
1120 | ret_val = -ENOMEM; | |
1121 | goto done; | |
1122 | } | |
1123 | ||
1124 | ret_val = count; | |
1125 | pci_dev_put(pdev); | |
1126 | goto done; | |
1127 | ||
1128 | ||
1129 | } else if (strncmp(curr_pos, "decodes ", 8) == 0) { | |
1130 | curr_pos += 8; | |
1131 | remaining -= 8; | |
8b7e2e86 | 1132 | pr_debug("client 0x%p called 'decodes'\n", priv); |
deb2d2ec BH |
1133 | |
1134 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1135 | ret_val = -EPROTO; | |
1136 | goto done; | |
1137 | } | |
1138 | pdev = priv->target; | |
1139 | if (priv->target == NULL) { | |
1140 | ret_val = -ENODEV; | |
1141 | goto done; | |
1142 | } | |
1143 | ||
1144 | __vga_set_legacy_decoding(pdev, io_state, true); | |
1145 | ret_val = count; | |
1146 | goto done; | |
1147 | } | |
1148 | /* If we got here, the message written is not part of the protocol! */ | |
1149 | kfree(kbuf); | |
1150 | return -EPROTO; | |
1151 | ||
1152 | done: | |
1153 | kfree(kbuf); | |
1154 | return ret_val; | |
1155 | } | |
1156 | ||
1157 | static unsigned int vga_arb_fpoll(struct file *file, poll_table * wait) | |
1158 | { | |
1159 | struct vga_arb_private *priv = file->private_data; | |
1160 | ||
2d6e9b91 | 1161 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1162 | |
1163 | if (priv == NULL) | |
1164 | return -ENODEV; | |
1165 | poll_wait(file, &vga_wait_queue, wait); | |
1166 | return POLLIN; | |
1167 | } | |
1168 | ||
1169 | static int vga_arb_open(struct inode *inode, struct file *file) | |
1170 | { | |
1171 | struct vga_arb_private *priv; | |
1172 | unsigned long flags; | |
1173 | ||
2d6e9b91 | 1174 | pr_debug("%s\n", __func__); |
deb2d2ec | 1175 | |
f35119d6 | 1176 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); |
deb2d2ec BH |
1177 | if (priv == NULL) |
1178 | return -ENOMEM; | |
deb2d2ec BH |
1179 | spin_lock_init(&priv->lock); |
1180 | file->private_data = priv; | |
1181 | ||
1182 | spin_lock_irqsave(&vga_user_lock, flags); | |
1183 | list_add(&priv->list, &vga_user_list); | |
1184 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1185 | ||
1186 | /* Set the client' lists of locks */ | |
1187 | priv->target = vga_default_device(); /* Maybe this is still null! */ | |
1188 | priv->cards[0].pdev = priv->target; | |
1189 | priv->cards[0].io_cnt = 0; | |
1190 | priv->cards[0].mem_cnt = 0; | |
1191 | ||
1192 | ||
1193 | return 0; | |
1194 | } | |
1195 | ||
1196 | static int vga_arb_release(struct inode *inode, struct file *file) | |
1197 | { | |
1198 | struct vga_arb_private *priv = file->private_data; | |
1199 | struct vga_arb_user_card *uc; | |
1200 | unsigned long flags; | |
1201 | int i; | |
1202 | ||
2d6e9b91 | 1203 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1204 | |
1205 | if (priv == NULL) | |
1206 | return -ENODEV; | |
1207 | ||
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) { | |
1253 | new_decodes = vgadev->set_vga_decode(vgadev->cookie, new_state); | |
1254 | vga_update_device_decodes(vgadev, new_decodes); | |
1255 | } | |
1256 | } | |
1257 | spin_unlock_irqrestore(&vga_lock, flags); | |
1258 | } | |
1259 | ||
1260 | static int pci_notify(struct notifier_block *nb, unsigned long action, | |
1261 | void *data) | |
1262 | { | |
1263 | struct device *dev = data; | |
1264 | struct pci_dev *pdev = to_pci_dev(dev); | |
1265 | bool notify = false; | |
1266 | ||
2d6e9b91 | 1267 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1268 | |
1269 | /* For now we're only intereted in devices added and removed. I didn't | |
1270 | * test this thing here, so someone needs to double check for the | |
1271 | * cases of hotplugable vga cards. */ | |
1272 | if (action == BUS_NOTIFY_ADD_DEVICE) | |
1273 | notify = vga_arbiter_add_pci_device(pdev); | |
1274 | else if (action == BUS_NOTIFY_DEL_DEVICE) | |
1275 | notify = vga_arbiter_del_pci_device(pdev); | |
1276 | ||
1277 | if (notify) | |
1278 | vga_arbiter_notify_clients(); | |
1279 | return 0; | |
1280 | } | |
1281 | ||
1282 | static struct notifier_block pci_notifier = { | |
1283 | .notifier_call = pci_notify, | |
1284 | }; | |
1285 | ||
1286 | static const struct file_operations vga_arb_device_fops = { | |
1287 | .read = vga_arb_read, | |
1288 | .write = vga_arb_write, | |
1289 | .poll = vga_arb_fpoll, | |
1290 | .open = vga_arb_open, | |
1291 | .release = vga_arb_release, | |
6038f373 | 1292 | .llseek = noop_llseek, |
deb2d2ec BH |
1293 | }; |
1294 | ||
1295 | static struct miscdevice vga_arb_device = { | |
1296 | MISC_DYNAMIC_MINOR, "vga_arbiter", &vga_arb_device_fops | |
1297 | }; | |
1298 | ||
1299 | static int __init vga_arb_device_init(void) | |
1300 | { | |
1301 | int rc; | |
1302 | struct pci_dev *pdev; | |
3448a19d | 1303 | struct vga_device *vgadev; |
deb2d2ec BH |
1304 | |
1305 | rc = misc_register(&vga_arb_device); | |
1306 | if (rc < 0) | |
8b7e2e86 | 1307 | pr_err("error %d registering device\n", rc); |
deb2d2ec BH |
1308 | |
1309 | bus_register_notifier(&pci_bus_type, &pci_notifier); | |
1310 | ||
1311 | /* We add all pci devices satisfying vga class in the arbiter by | |
1312 | * default */ | |
1313 | pdev = NULL; | |
1314 | while ((pdev = | |
1315 | pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, | |
1316 | PCI_ANY_ID, pdev)) != NULL) | |
1317 | vga_arbiter_add_pci_device(pdev); | |
1318 | ||
8b7e2e86 | 1319 | pr_info("loaded\n"); |
3448a19d DA |
1320 | |
1321 | list_for_each_entry(vgadev, &vga_list, list) { | |
86fd887b BP |
1322 | #if defined(CONFIG_X86) || defined(CONFIG_IA64) |
1323 | /* Override I/O based detection done by vga_arbiter_add_pci_device() | |
1324 | * as it may take the wrong device (e.g. on Apple system under EFI). | |
1325 | * | |
1326 | * Select the device owning the boot framebuffer if there is one. | |
1327 | */ | |
1328 | resource_size_t start, end; | |
1329 | int i; | |
1330 | ||
1331 | /* Does firmware framebuffer belong to us? */ | |
1332 | for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) { | |
1333 | if (!(pci_resource_flags(vgadev->pdev, i) & IORESOURCE_MEM)) | |
1334 | continue; | |
1335 | ||
1336 | start = pci_resource_start(vgadev->pdev, i); | |
1337 | end = pci_resource_end(vgadev->pdev, i); | |
1338 | ||
1339 | if (!start || !end) | |
1340 | continue; | |
1341 | ||
1342 | if (screen_info.lfb_base < start || | |
1343 | (screen_info.lfb_base + screen_info.lfb_size) >= end) | |
1344 | continue; | |
1345 | if (!vga_default_device()) | |
8b7e2e86 | 1346 | pr_info("setting as boot device: PCI:%s\n", |
86fd887b BP |
1347 | pci_name(vgadev->pdev)); |
1348 | else if (vgadev->pdev != vga_default_device()) | |
8b7e2e86 | 1349 | pr_info("overriding boot device: PCI:%s\n", |
86fd887b BP |
1350 | pci_name(vgadev->pdev)); |
1351 | vga_set_default_device(vgadev->pdev); | |
1352 | } | |
1353 | #endif | |
3448a19d | 1354 | if (vgadev->bridge_has_one_vga) |
8b7e2e86 | 1355 | pr_info("bridge control possible %s\n", pci_name(vgadev->pdev)); |
3448a19d | 1356 | else |
8b7e2e86 | 1357 | pr_info("no bridge control possible %s\n", pci_name(vgadev->pdev)); |
3448a19d | 1358 | } |
deb2d2ec BH |
1359 | return rc; |
1360 | } | |
1361 | subsys_initcall(vga_arb_device_init); |