xref: /openbmc/linux/drivers/vfio/platform/vfio_platform_common.c (revision 4baf4a2919b2a13a7f67d63f34b03f823ea7c0e8)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2013 - Virtual Open Systems
4  * Author: Antonios Motakis <a.motakis@virtualopensystems.com>
5  */
6 
7 #define dev_fmt(fmt)	"VFIO: " fmt
8 
9 #include <linux/device.h>
10 #include <linux/acpi.h>
11 #include <linux/iommu.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/slab.h>
16 #include <linux/types.h>
17 #include <linux/uaccess.h>
18 #include <linux/vfio.h>
19 
20 #include "vfio_platform_private.h"
21 
22 #define DRIVER_VERSION  "0.10"
23 #define DRIVER_AUTHOR   "Antonios Motakis <a.motakis@virtualopensystems.com>"
24 #define DRIVER_DESC     "VFIO platform base module"
25 
26 #define VFIO_PLATFORM_IS_ACPI(vdev) ((vdev)->acpihid != NULL)
27 
28 static LIST_HEAD(reset_list);
29 static DEFINE_MUTEX(driver_lock);
30 
vfio_platform_lookup_reset(const char * compat,struct module ** module)31 static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
32 					struct module **module)
33 {
34 	struct vfio_platform_reset_node *iter;
35 	vfio_platform_reset_fn_t reset_fn = NULL;
36 
37 	mutex_lock(&driver_lock);
38 	list_for_each_entry(iter, &reset_list, link) {
39 		if (!strcmp(iter->compat, compat) &&
40 			try_module_get(iter->owner)) {
41 			*module = iter->owner;
42 			reset_fn = iter->of_reset;
43 			break;
44 		}
45 	}
46 	mutex_unlock(&driver_lock);
47 	return reset_fn;
48 }
49 
vfio_platform_acpi_probe(struct vfio_platform_device * vdev,struct device * dev)50 static int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
51 				    struct device *dev)
52 {
53 	struct acpi_device *adev;
54 
55 	if (acpi_disabled)
56 		return -ENOENT;
57 
58 	adev = ACPI_COMPANION(dev);
59 	if (!adev) {
60 		dev_err(dev, "ACPI companion device not found for %s\n",
61 			vdev->name);
62 		return -ENODEV;
63 	}
64 
65 #ifdef CONFIG_ACPI
66 	vdev->acpihid = acpi_device_hid(adev);
67 #endif
68 	return WARN_ON(!vdev->acpihid) ? -EINVAL : 0;
69 }
70 
vfio_platform_acpi_call_reset(struct vfio_platform_device * vdev,const char ** extra_dbg)71 static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev,
72 				  const char **extra_dbg)
73 {
74 #ifdef CONFIG_ACPI
75 	struct device *dev = vdev->device;
76 	acpi_handle handle = ACPI_HANDLE(dev);
77 	acpi_status acpi_ret;
78 
79 	acpi_ret = acpi_evaluate_object(handle, "_RST", NULL, NULL);
80 	if (ACPI_FAILURE(acpi_ret)) {
81 		if (extra_dbg)
82 			*extra_dbg = acpi_format_exception(acpi_ret);
83 		return -EINVAL;
84 	}
85 
86 	return 0;
87 #else
88 	return -ENOENT;
89 #endif
90 }
91 
vfio_platform_acpi_has_reset(struct vfio_platform_device * vdev)92 static bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
93 {
94 #ifdef CONFIG_ACPI
95 	struct device *dev = vdev->device;
96 	acpi_handle handle = ACPI_HANDLE(dev);
97 
98 	return acpi_has_method(handle, "_RST");
99 #else
100 	return false;
101 #endif
102 }
103 
vfio_platform_has_reset(struct vfio_platform_device * vdev)104 static bool vfio_platform_has_reset(struct vfio_platform_device *vdev)
105 {
106 	if (VFIO_PLATFORM_IS_ACPI(vdev))
107 		return vfio_platform_acpi_has_reset(vdev);
108 
109 	return vdev->of_reset ? true : false;
110 }
111 
vfio_platform_get_reset(struct vfio_platform_device * vdev)112 static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
113 {
114 	if (VFIO_PLATFORM_IS_ACPI(vdev))
115 		return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT;
116 
117 	vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
118 						    &vdev->reset_module);
119 	if (!vdev->of_reset) {
120 		request_module("vfio-reset:%s", vdev->compat);
121 		vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
122 							&vdev->reset_module);
123 	}
124 
125 	return vdev->of_reset ? 0 : -ENOENT;
126 }
127 
vfio_platform_put_reset(struct vfio_platform_device * vdev)128 static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
129 {
130 	if (VFIO_PLATFORM_IS_ACPI(vdev))
131 		return;
132 
133 	if (vdev->of_reset)
134 		module_put(vdev->reset_module);
135 }
136 
vfio_platform_regions_init(struct vfio_platform_device * vdev)137 static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
138 {
139 	int cnt = 0, i;
140 
141 	while (vdev->get_resource(vdev, cnt))
142 		cnt++;
143 
144 	vdev->regions = kcalloc(cnt, sizeof(struct vfio_platform_region),
145 				GFP_KERNEL_ACCOUNT);
146 	if (!vdev->regions)
147 		return -ENOMEM;
148 
149 	for (i = 0; i < cnt;  i++) {
150 		struct resource *res =
151 			vdev->get_resource(vdev, i);
152 
153 		vdev->regions[i].addr = res->start;
154 		vdev->regions[i].size = resource_size(res);
155 		vdev->regions[i].flags = 0;
156 
157 		switch (resource_type(res)) {
158 		case IORESOURCE_MEM:
159 			vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_MMIO;
160 			vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
161 			if (!(res->flags & IORESOURCE_READONLY))
162 				vdev->regions[i].flags |=
163 					VFIO_REGION_INFO_FLAG_WRITE;
164 
165 			/*
166 			 * Only regions addressed with PAGE granularity may be
167 			 * MMAPed securely.
168 			 */
169 			if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
170 					!(vdev->regions[i].size & ~PAGE_MASK))
171 				vdev->regions[i].flags |=
172 					VFIO_REGION_INFO_FLAG_MMAP;
173 
174 			break;
175 		case IORESOURCE_IO:
176 			vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_PIO;
177 			break;
178 		default:
179 			goto err;
180 		}
181 	}
182 
183 	vdev->num_regions = cnt;
184 
185 	return 0;
186 err:
187 	kfree(vdev->regions);
188 	return -EINVAL;
189 }
190 
vfio_platform_regions_cleanup(struct vfio_platform_device * vdev)191 static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
192 {
193 	int i;
194 
195 	for (i = 0; i < vdev->num_regions; i++)
196 		iounmap(vdev->regions[i].ioaddr);
197 
198 	vdev->num_regions = 0;
199 	kfree(vdev->regions);
200 }
201 
vfio_platform_call_reset(struct vfio_platform_device * vdev,const char ** extra_dbg)202 static int vfio_platform_call_reset(struct vfio_platform_device *vdev,
203 				    const char **extra_dbg)
204 {
205 	if (VFIO_PLATFORM_IS_ACPI(vdev)) {
206 		dev_info(vdev->device, "reset\n");
207 		return vfio_platform_acpi_call_reset(vdev, extra_dbg);
208 	} else if (vdev->of_reset) {
209 		dev_info(vdev->device, "reset\n");
210 		return vdev->of_reset(vdev);
211 	}
212 
213 	dev_warn(vdev->device, "no reset function found!\n");
214 	return -EINVAL;
215 }
216 
vfio_platform_close_device(struct vfio_device * core_vdev)217 void vfio_platform_close_device(struct vfio_device *core_vdev)
218 {
219 	struct vfio_platform_device *vdev =
220 		container_of(core_vdev, struct vfio_platform_device, vdev);
221 	const char *extra_dbg = NULL;
222 	int ret;
223 
224 	ret = vfio_platform_call_reset(vdev, &extra_dbg);
225 	if (WARN_ON(ret && vdev->reset_required)) {
226 		dev_warn(
227 			vdev->device,
228 			"reset driver is required and reset call failed in release (%d) %s\n",
229 			ret, extra_dbg ? extra_dbg : "");
230 	}
231 	pm_runtime_put(vdev->device);
232 	vfio_platform_regions_cleanup(vdev);
233 	vfio_platform_irq_cleanup(vdev);
234 }
235 EXPORT_SYMBOL_GPL(vfio_platform_close_device);
236 
vfio_platform_open_device(struct vfio_device * core_vdev)237 int vfio_platform_open_device(struct vfio_device *core_vdev)
238 {
239 	struct vfio_platform_device *vdev =
240 		container_of(core_vdev, struct vfio_platform_device, vdev);
241 	const char *extra_dbg = NULL;
242 	int ret;
243 
244 	ret = vfio_platform_regions_init(vdev);
245 	if (ret)
246 		return ret;
247 
248 	ret = vfio_platform_irq_init(vdev);
249 	if (ret)
250 		goto err_irq;
251 
252 	ret = pm_runtime_get_sync(vdev->device);
253 	if (ret < 0)
254 		goto err_rst;
255 
256 	ret = vfio_platform_call_reset(vdev, &extra_dbg);
257 	if (ret && vdev->reset_required) {
258 		dev_warn(
259 			vdev->device,
260 			"reset driver is required and reset call failed in open (%d) %s\n",
261 			ret, extra_dbg ? extra_dbg : "");
262 		goto err_rst;
263 	}
264 	return 0;
265 
266 err_rst:
267 	pm_runtime_put(vdev->device);
268 	vfio_platform_irq_cleanup(vdev);
269 err_irq:
270 	vfio_platform_regions_cleanup(vdev);
271 	return ret;
272 }
273 EXPORT_SYMBOL_GPL(vfio_platform_open_device);
274 
vfio_platform_ioctl(struct vfio_device * core_vdev,unsigned int cmd,unsigned long arg)275 long vfio_platform_ioctl(struct vfio_device *core_vdev,
276 			 unsigned int cmd, unsigned long arg)
277 {
278 	struct vfio_platform_device *vdev =
279 		container_of(core_vdev, struct vfio_platform_device, vdev);
280 
281 	unsigned long minsz;
282 
283 	if (cmd == VFIO_DEVICE_GET_INFO) {
284 		struct vfio_device_info info;
285 
286 		minsz = offsetofend(struct vfio_device_info, num_irqs);
287 
288 		if (copy_from_user(&info, (void __user *)arg, minsz))
289 			return -EFAULT;
290 
291 		if (info.argsz < minsz)
292 			return -EINVAL;
293 
294 		if (vfio_platform_has_reset(vdev))
295 			vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
296 		info.flags = vdev->flags;
297 		info.num_regions = vdev->num_regions;
298 		info.num_irqs = vdev->num_irqs;
299 
300 		return copy_to_user((void __user *)arg, &info, minsz) ?
301 			-EFAULT : 0;
302 
303 	} else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
304 		struct vfio_region_info info;
305 
306 		minsz = offsetofend(struct vfio_region_info, offset);
307 
308 		if (copy_from_user(&info, (void __user *)arg, minsz))
309 			return -EFAULT;
310 
311 		if (info.argsz < minsz)
312 			return -EINVAL;
313 
314 		if (info.index >= vdev->num_regions)
315 			return -EINVAL;
316 
317 		/* map offset to the physical address  */
318 		info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
319 		info.size = vdev->regions[info.index].size;
320 		info.flags = vdev->regions[info.index].flags;
321 
322 		return copy_to_user((void __user *)arg, &info, minsz) ?
323 			-EFAULT : 0;
324 
325 	} else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
326 		struct vfio_irq_info info;
327 
328 		minsz = offsetofend(struct vfio_irq_info, count);
329 
330 		if (copy_from_user(&info, (void __user *)arg, minsz))
331 			return -EFAULT;
332 
333 		if (info.argsz < minsz)
334 			return -EINVAL;
335 
336 		if (info.index >= vdev->num_irqs)
337 			return -EINVAL;
338 
339 		info.flags = vdev->irqs[info.index].flags;
340 		info.count = vdev->irqs[info.index].count;
341 
342 		return copy_to_user((void __user *)arg, &info, minsz) ?
343 			-EFAULT : 0;
344 
345 	} else if (cmd == VFIO_DEVICE_SET_IRQS) {
346 		struct vfio_irq_set hdr;
347 		u8 *data = NULL;
348 		int ret = 0;
349 		size_t data_size = 0;
350 
351 		minsz = offsetofend(struct vfio_irq_set, count);
352 
353 		if (copy_from_user(&hdr, (void __user *)arg, minsz))
354 			return -EFAULT;
355 
356 		ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
357 						 vdev->num_irqs, &data_size);
358 		if (ret)
359 			return ret;
360 
361 		if (data_size) {
362 			data = memdup_user((void __user *)(arg + minsz),
363 					    data_size);
364 			if (IS_ERR(data))
365 				return PTR_ERR(data);
366 		}
367 
368 		mutex_lock(&vdev->igate);
369 
370 		ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
371 						   hdr.start, hdr.count, data);
372 		mutex_unlock(&vdev->igate);
373 		kfree(data);
374 
375 		return ret;
376 
377 	} else if (cmd == VFIO_DEVICE_RESET) {
378 		return vfio_platform_call_reset(vdev, NULL);
379 	}
380 
381 	return -ENOTTY;
382 }
383 EXPORT_SYMBOL_GPL(vfio_platform_ioctl);
384 
vfio_platform_read_mmio(struct vfio_platform_region * reg,char __user * buf,size_t count,loff_t off)385 static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
386 				       char __user *buf, size_t count,
387 				       loff_t off)
388 {
389 	unsigned int done = 0;
390 
391 	if (off >= reg->size)
392 		return -EINVAL;
393 
394 	count = min_t(size_t, count, reg->size - off);
395 
396 	if (!reg->ioaddr) {
397 		reg->ioaddr =
398 			ioremap(reg->addr, reg->size);
399 
400 		if (!reg->ioaddr)
401 			return -ENOMEM;
402 	}
403 
404 	while (count) {
405 		size_t filled;
406 
407 		if (count >= 4 && !(off % 4)) {
408 			u32 val;
409 
410 			val = ioread32(reg->ioaddr + off);
411 			if (copy_to_user(buf, &val, 4))
412 				goto err;
413 
414 			filled = 4;
415 		} else if (count >= 2 && !(off % 2)) {
416 			u16 val;
417 
418 			val = ioread16(reg->ioaddr + off);
419 			if (copy_to_user(buf, &val, 2))
420 				goto err;
421 
422 			filled = 2;
423 		} else {
424 			u8 val;
425 
426 			val = ioread8(reg->ioaddr + off);
427 			if (copy_to_user(buf, &val, 1))
428 				goto err;
429 
430 			filled = 1;
431 		}
432 
433 
434 		count -= filled;
435 		done += filled;
436 		off += filled;
437 		buf += filled;
438 	}
439 
440 	return done;
441 err:
442 	return -EFAULT;
443 }
444 
vfio_platform_read(struct vfio_device * core_vdev,char __user * buf,size_t count,loff_t * ppos)445 ssize_t vfio_platform_read(struct vfio_device *core_vdev,
446 			   char __user *buf, size_t count, loff_t *ppos)
447 {
448 	struct vfio_platform_device *vdev =
449 		container_of(core_vdev, struct vfio_platform_device, vdev);
450 	unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
451 	loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
452 
453 	if (index >= vdev->num_regions)
454 		return -EINVAL;
455 
456 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
457 		return -EINVAL;
458 
459 	if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
460 		return vfio_platform_read_mmio(&vdev->regions[index],
461 							buf, count, off);
462 	else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
463 		return -EINVAL; /* not implemented */
464 
465 	return -EINVAL;
466 }
467 EXPORT_SYMBOL_GPL(vfio_platform_read);
468 
vfio_platform_write_mmio(struct vfio_platform_region * reg,const char __user * buf,size_t count,loff_t off)469 static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
470 					const char __user *buf, size_t count,
471 					loff_t off)
472 {
473 	unsigned int done = 0;
474 
475 	if (off >= reg->size)
476 		return -EINVAL;
477 
478 	count = min_t(size_t, count, reg->size - off);
479 
480 	if (!reg->ioaddr) {
481 		reg->ioaddr =
482 			ioremap(reg->addr, reg->size);
483 
484 		if (!reg->ioaddr)
485 			return -ENOMEM;
486 	}
487 
488 	while (count) {
489 		size_t filled;
490 
491 		if (count >= 4 && !(off % 4)) {
492 			u32 val;
493 
494 			if (copy_from_user(&val, buf, 4))
495 				goto err;
496 			iowrite32(val, reg->ioaddr + off);
497 
498 			filled = 4;
499 		} else if (count >= 2 && !(off % 2)) {
500 			u16 val;
501 
502 			if (copy_from_user(&val, buf, 2))
503 				goto err;
504 			iowrite16(val, reg->ioaddr + off);
505 
506 			filled = 2;
507 		} else {
508 			u8 val;
509 
510 			if (copy_from_user(&val, buf, 1))
511 				goto err;
512 			iowrite8(val, reg->ioaddr + off);
513 
514 			filled = 1;
515 		}
516 
517 		count -= filled;
518 		done += filled;
519 		off += filled;
520 		buf += filled;
521 	}
522 
523 	return done;
524 err:
525 	return -EFAULT;
526 }
527 
vfio_platform_write(struct vfio_device * core_vdev,const char __user * buf,size_t count,loff_t * ppos)528 ssize_t vfio_platform_write(struct vfio_device *core_vdev, const char __user *buf,
529 			    size_t count, loff_t *ppos)
530 {
531 	struct vfio_platform_device *vdev =
532 		container_of(core_vdev, struct vfio_platform_device, vdev);
533 	unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
534 	loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
535 
536 	if (index >= vdev->num_regions)
537 		return -EINVAL;
538 
539 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
540 		return -EINVAL;
541 
542 	if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
543 		return vfio_platform_write_mmio(&vdev->regions[index],
544 							buf, count, off);
545 	else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
546 		return -EINVAL; /* not implemented */
547 
548 	return -EINVAL;
549 }
550 EXPORT_SYMBOL_GPL(vfio_platform_write);
551 
vfio_platform_mmap_mmio(struct vfio_platform_region region,struct vm_area_struct * vma)552 static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
553 				   struct vm_area_struct *vma)
554 {
555 	u64 req_len, pgoff, req_start;
556 
557 	req_len = vma->vm_end - vma->vm_start;
558 	pgoff = vma->vm_pgoff &
559 		((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
560 	req_start = pgoff << PAGE_SHIFT;
561 
562 	if (region.size < PAGE_SIZE || req_start + req_len > region.size)
563 		return -EINVAL;
564 
565 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
566 	vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
567 
568 	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
569 			       req_len, vma->vm_page_prot);
570 }
571 
vfio_platform_mmap(struct vfio_device * core_vdev,struct vm_area_struct * vma)572 int vfio_platform_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
573 {
574 	struct vfio_platform_device *vdev =
575 		container_of(core_vdev, struct vfio_platform_device, vdev);
576 	unsigned int index;
577 
578 	index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
579 
580 	if (vma->vm_end < vma->vm_start)
581 		return -EINVAL;
582 	if (!(vma->vm_flags & VM_SHARED))
583 		return -EINVAL;
584 	if (index >= vdev->num_regions)
585 		return -EINVAL;
586 	if (vma->vm_start & ~PAGE_MASK)
587 		return -EINVAL;
588 	if (vma->vm_end & ~PAGE_MASK)
589 		return -EINVAL;
590 
591 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
592 		return -EINVAL;
593 
594 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
595 			&& (vma->vm_flags & VM_READ))
596 		return -EINVAL;
597 
598 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
599 			&& (vma->vm_flags & VM_WRITE))
600 		return -EINVAL;
601 
602 	vma->vm_private_data = vdev;
603 
604 	if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
605 		return vfio_platform_mmap_mmio(vdev->regions[index], vma);
606 
607 	else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
608 		return -EINVAL; /* not implemented */
609 
610 	return -EINVAL;
611 }
612 EXPORT_SYMBOL_GPL(vfio_platform_mmap);
613 
vfio_platform_of_probe(struct vfio_platform_device * vdev,struct device * dev)614 static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
615 			   struct device *dev)
616 {
617 	int ret;
618 
619 	ret = device_property_read_string(dev, "compatible",
620 					  &vdev->compat);
621 	if (ret)
622 		dev_err(dev, "Cannot retrieve compat for %s\n", vdev->name);
623 
624 	return ret;
625 }
626 
627 /*
628  * There can be two kernel build combinations. One build where
629  * ACPI is not selected in Kconfig and another one with the ACPI Kconfig.
630  *
631  * In the first case, vfio_platform_acpi_probe will return since
632  * acpi_disabled is 1. DT user will not see any kind of messages from
633  * ACPI.
634  *
635  * In the second case, both DT and ACPI is compiled in but the system is
636  * booting with any of these combinations.
637  *
638  * If the firmware is DT type, then acpi_disabled is 1. The ACPI probe routine
639  * terminates immediately without any messages.
640  *
641  * If the firmware is ACPI type, then acpi_disabled is 0. All other checks are
642  * valid checks. We cannot claim that this system is DT.
643  */
vfio_platform_init_common(struct vfio_platform_device * vdev)644 int vfio_platform_init_common(struct vfio_platform_device *vdev)
645 {
646 	int ret;
647 	struct device *dev = vdev->vdev.dev;
648 
649 	ret = vfio_platform_acpi_probe(vdev, dev);
650 	if (ret)
651 		ret = vfio_platform_of_probe(vdev, dev);
652 
653 	if (ret)
654 		return ret;
655 
656 	vdev->device = dev;
657 	mutex_init(&vdev->igate);
658 
659 	ret = vfio_platform_get_reset(vdev);
660 	if (ret && vdev->reset_required) {
661 		dev_err(dev, "No reset function found for device %s\n",
662 			vdev->name);
663 		return ret;
664 	}
665 
666 	return 0;
667 }
668 EXPORT_SYMBOL_GPL(vfio_platform_init_common);
669 
vfio_platform_release_common(struct vfio_platform_device * vdev)670 void vfio_platform_release_common(struct vfio_platform_device *vdev)
671 {
672 	vfio_platform_put_reset(vdev);
673 }
674 EXPORT_SYMBOL_GPL(vfio_platform_release_common);
675 
__vfio_platform_register_reset(struct vfio_platform_reset_node * node)676 void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
677 {
678 	mutex_lock(&driver_lock);
679 	list_add(&node->link, &reset_list);
680 	mutex_unlock(&driver_lock);
681 }
682 EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
683 
vfio_platform_unregister_reset(const char * compat,vfio_platform_reset_fn_t fn)684 void vfio_platform_unregister_reset(const char *compat,
685 				    vfio_platform_reset_fn_t fn)
686 {
687 	struct vfio_platform_reset_node *iter, *temp;
688 
689 	mutex_lock(&driver_lock);
690 	list_for_each_entry_safe(iter, temp, &reset_list, link) {
691 		if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
692 			list_del(&iter->link);
693 			break;
694 		}
695 	}
696 
697 	mutex_unlock(&driver_lock);
698 
699 }
700 EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
701 
702 MODULE_VERSION(DRIVER_VERSION);
703 MODULE_LICENSE("GPL v2");
704 MODULE_AUTHOR(DRIVER_AUTHOR);
705 MODULE_DESCRIPTION(DRIVER_DESC);
706