blob: 00d115b22bd8b322be6b5d7b090eaa4fa42eab11 [file] [log] [blame]
Pawel Molledfd52e2011-10-24 14:07:03 +01001/*
2 * Virtio memory mapped device driver
3 *
4 * Copyright 2011, ARM Ltd.
5 *
6 * This module allows virtio devices to be used over a virtual, memory mapped
7 * platform device.
8 *
Pawel Moll81a054c2012-05-09 18:30:16 +01009 * The guest device(s) may be instantiated in one of three equivalent ways:
10 *
11 * 1. Static platform device in board's code, eg.:
12 *
13 * static struct platform_device v2m_virtio_device = {
14 * .name = "virtio-mmio",
15 * .id = -1,
16 * .num_resources = 2,
17 * .resource = (struct resource []) {
18 * {
19 * .start = 0x1001e000,
20 * .end = 0x1001e0ff,
21 * .flags = IORESOURCE_MEM,
22 * }, {
23 * .start = 42 + 32,
24 * .end = 42 + 32,
25 * .flags = IORESOURCE_IRQ,
26 * },
27 * }
28 * };
29 *
30 * 2. Device Tree node, eg.:
31 *
32 * virtio_block@1e000 {
33 * compatible = "virtio,mmio";
34 * reg = <0x1e000 0x100>;
35 * interrupts = <42>;
36 * }
37 *
38 * 3. Kernel module (or command line) parameter. Can be used more than once -
39 * one device will be created for each one. Syntax:
40 *
41 * [virtio_mmio.]device=<size>@<baseaddr>:<irq>[:<id>]
42 * where:
43 * <size> := size (can use standard suffixes like K, M or G)
44 * <baseaddr> := physical base address
45 * <irq> := interrupt number (as passed to request_irq())
46 * <id> := (optional) platform device id
47 * eg.:
48 * virtio_mmio.device=0x100@0x100b0000:48 \
49 * virtio_mmio.device=1K@0x1001e000:74
50 *
51 *
52 *
Pawel Molledfd52e2011-10-24 14:07:03 +010053 * Registers layout (all 32-bit wide):
54 *
55 * offset d. name description
56 * ------ -- ---------------- -----------------
57 *
58 * 0x000 R MagicValue Magic value "virt"
59 * 0x004 R Version Device version (current max. 1)
60 * 0x008 R DeviceID Virtio device ID
61 * 0x00c R VendorID Virtio vendor ID
62 *
63 * 0x010 R HostFeatures Features supported by the host
64 * 0x014 W HostFeaturesSel Set of host features to access via HostFeatures
65 *
66 * 0x020 W GuestFeatures Features activated by the guest
67 * 0x024 W GuestFeaturesSel Set of activated features to set via GuestFeatures
68 * 0x028 W GuestPageSize Size of guest's memory page in bytes
69 *
70 * 0x030 W QueueSel Queue selector
71 * 0x034 R QueueNumMax Maximum size of the currently selected queue
72 * 0x038 W QueueNum Queue size for the currently selected queue
73 * 0x03c W QueueAlign Used Ring alignment for the current queue
74 * 0x040 RW QueuePFN PFN for the currently selected queue
75 *
76 * 0x050 W QueueNotify Queue notifier
77 * 0x060 R InterruptStatus Interrupt status register
Ryota Ozaki0d34cc22013-02-04 10:35:30 +103078 * 0x064 W InterruptACK Interrupt acknowledge register
Pawel Molledfd52e2011-10-24 14:07:03 +010079 * 0x070 RW Status Device status register
80 *
81 * 0x100+ RW Device-specific configuration space
82 *
83 * Based on Virtio PCI driver by Anthony Liguori, copyright IBM Corp. 2007
84 *
85 * This work is licensed under the terms of the GNU GPL, version 2 or later.
86 * See the COPYING file in the top-level directory.
87 */
88
Pawel Moll81a054c2012-05-09 18:30:16 +010089#define pr_fmt(fmt) "virtio-mmio: " fmt
90
Pawel Molledfd52e2011-10-24 14:07:03 +010091#include <linux/highmem.h>
92#include <linux/interrupt.h>
93#include <linux/io.h>
94#include <linux/list.h>
95#include <linux/module.h>
96#include <linux/platform_device.h>
97#include <linux/slab.h>
98#include <linux/spinlock.h>
99#include <linux/virtio.h>
100#include <linux/virtio_config.h>
101#include <linux/virtio_mmio.h>
102#include <linux/virtio_ring.h>
103
104
105
106/* The alignment to use between consumer and producer parts of vring.
107 * Currently hardcoded to the page size. */
108#define VIRTIO_MMIO_VRING_ALIGN PAGE_SIZE
109
110
111
112#define to_virtio_mmio_device(_plat_dev) \
113 container_of(_plat_dev, struct virtio_mmio_device, vdev)
114
115struct virtio_mmio_device {
116 struct virtio_device vdev;
117 struct platform_device *pdev;
118
119 void __iomem *base;
120 unsigned long version;
121
122 /* a list of queues so we can dispatch IRQs */
123 spinlock_t lock;
124 struct list_head virtqueues;
125};
126
127struct virtio_mmio_vq_info {
128 /* the actual virtqueue */
129 struct virtqueue *vq;
130
131 /* the number of entries in the queue */
132 unsigned int num;
133
Pawel Molledfd52e2011-10-24 14:07:03 +0100134 /* the virtual address of the ring queue */
135 void *queue;
136
137 /* the list node for the virtqueues list */
138 struct list_head node;
139};
140
141
142
143/* Configuration interface */
144
Michael S. Tsirkind0254772014-10-07 16:39:43 +0200145static u64 vm_get_features(struct virtio_device *vdev)
Pawel Molledfd52e2011-10-24 14:07:03 +0100146{
147 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
148
149 /* TODO: Features > 32 bits */
150 writel(0, vm_dev->base + VIRTIO_MMIO_HOST_FEATURES_SEL);
151
152 return readl(vm_dev->base + VIRTIO_MMIO_HOST_FEATURES);
153}
154
Michael S. Tsirkin5c609a52014-12-04 20:20:27 +0200155static int vm_finalize_features(struct virtio_device *vdev)
Pawel Molledfd52e2011-10-24 14:07:03 +0100156{
157 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
Pawel Molledfd52e2011-10-24 14:07:03 +0100158
159 /* Give virtio_ring a chance to accept features. */
160 vring_transport_features(vdev);
161
Michael S. Tsirkin93d389f2014-11-27 13:45:58 +0200162 /* Make sure we don't have any features > 32 bits! */
163 BUG_ON((u32)vdev->features != vdev->features);
164
Michael S. Tsirkine16e12b2014-10-07 16:39:42 +0200165 writel(0, vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES_SEL);
166 writel(vdev->features, vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES);
Michael S. Tsirkin5c609a52014-12-04 20:20:27 +0200167
168 return 0;
Pawel Molledfd52e2011-10-24 14:07:03 +0100169}
170
171static void vm_get(struct virtio_device *vdev, unsigned offset,
172 void *buf, unsigned len)
173{
174 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
175 u8 *ptr = buf;
176 int i;
177
178 for (i = 0; i < len; i++)
179 ptr[i] = readb(vm_dev->base + VIRTIO_MMIO_CONFIG + offset + i);
180}
181
182static void vm_set(struct virtio_device *vdev, unsigned offset,
183 const void *buf, unsigned len)
184{
185 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
186 const u8 *ptr = buf;
187 int i;
188
189 for (i = 0; i < len; i++)
190 writeb(ptr[i], vm_dev->base + VIRTIO_MMIO_CONFIG + offset + i);
191}
192
193static u8 vm_get_status(struct virtio_device *vdev)
194{
195 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
196
197 return readl(vm_dev->base + VIRTIO_MMIO_STATUS) & 0xff;
198}
199
200static void vm_set_status(struct virtio_device *vdev, u8 status)
201{
202 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
203
204 /* We should never be setting status to 0. */
205 BUG_ON(status == 0);
206
207 writel(status, vm_dev->base + VIRTIO_MMIO_STATUS);
208}
209
210static void vm_reset(struct virtio_device *vdev)
211{
212 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
213
214 /* 0 status means a reset. */
215 writel(0, vm_dev->base + VIRTIO_MMIO_STATUS);
216}
217
218
219
220/* Transport interface */
221
222/* the notify function used when creating a virt queue */
Heinz Graalfs46f9c2b2013-10-29 09:38:50 +1030223static bool vm_notify(struct virtqueue *vq)
Pawel Molledfd52e2011-10-24 14:07:03 +0100224{
225 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
Pawel Molledfd52e2011-10-24 14:07:03 +0100226
227 /* We write the queue's selector into the notification register to
228 * signal the other end */
Rusty Russell06ca2872012-10-16 23:56:14 +1030229 writel(vq->index, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY);
Heinz Graalfs46f9c2b2013-10-29 09:38:50 +1030230 return true;
Pawel Molledfd52e2011-10-24 14:07:03 +0100231}
232
233/* Notify all virtqueues on an interrupt. */
234static irqreturn_t vm_interrupt(int irq, void *opaque)
235{
236 struct virtio_mmio_device *vm_dev = opaque;
237 struct virtio_mmio_vq_info *info;
Pawel Molledfd52e2011-10-24 14:07:03 +0100238 unsigned long status;
239 unsigned long flags;
240 irqreturn_t ret = IRQ_NONE;
241
242 /* Read and acknowledge interrupts */
243 status = readl(vm_dev->base + VIRTIO_MMIO_INTERRUPT_STATUS);
244 writel(status, vm_dev->base + VIRTIO_MMIO_INTERRUPT_ACK);
245
Michael S. Tsirkin016c98c2014-10-14 10:40:34 +1030246 if (unlikely(status & VIRTIO_MMIO_INT_CONFIG)) {
247 virtio_config_changed(&vm_dev->vdev);
Pawel Molledfd52e2011-10-24 14:07:03 +0100248 ret = IRQ_HANDLED;
249 }
250
251 if (likely(status & VIRTIO_MMIO_INT_VRING)) {
252 spin_lock_irqsave(&vm_dev->lock, flags);
253 list_for_each_entry(info, &vm_dev->virtqueues, node)
254 ret |= vring_interrupt(irq, info->vq);
255 spin_unlock_irqrestore(&vm_dev->lock, flags);
256 }
257
258 return ret;
259}
260
261
262
263static void vm_del_vq(struct virtqueue *vq)
264{
265 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
266 struct virtio_mmio_vq_info *info = vq->priv;
267 unsigned long flags, size;
Rusty Russell06ca2872012-10-16 23:56:14 +1030268 unsigned int index = vq->index;
Pawel Molledfd52e2011-10-24 14:07:03 +0100269
270 spin_lock_irqsave(&vm_dev->lock, flags);
271 list_del(&info->node);
272 spin_unlock_irqrestore(&vm_dev->lock, flags);
273
274 vring_del_virtqueue(vq);
275
276 /* Select and deactivate the queue */
Jason Wang17bb6d42012-08-28 13:54:13 +0200277 writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL);
Pawel Molledfd52e2011-10-24 14:07:03 +0100278 writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN);
279
280 size = PAGE_ALIGN(vring_size(info->num, VIRTIO_MMIO_VRING_ALIGN));
281 free_pages_exact(info->queue, size);
282 kfree(info);
283}
284
285static void vm_del_vqs(struct virtio_device *vdev)
286{
287 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
288 struct virtqueue *vq, *n;
289
290 list_for_each_entry_safe(vq, n, &vdev->vqs, list)
291 vm_del_vq(vq);
292
293 free_irq(platform_get_irq(vm_dev->pdev, 0), vm_dev);
294}
295
296
297
298static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index,
299 void (*callback)(struct virtqueue *vq),
300 const char *name)
301{
302 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
303 struct virtio_mmio_vq_info *info;
304 struct virtqueue *vq;
305 unsigned long flags, size;
306 int err;
307
Michael S. Tsirkin6457f122012-09-05 21:47:45 +0300308 if (!name)
309 return NULL;
310
Pawel Molledfd52e2011-10-24 14:07:03 +0100311 /* Select the queue we're interested in */
312 writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL);
313
314 /* Queue shouldn't already be set up. */
315 if (readl(vm_dev->base + VIRTIO_MMIO_QUEUE_PFN)) {
316 err = -ENOENT;
317 goto error_available;
318 }
319
320 /* Allocate and fill out our active queue description */
321 info = kmalloc(sizeof(*info), GFP_KERNEL);
322 if (!info) {
323 err = -ENOMEM;
324 goto error_kmalloc;
325 }
Pawel Molledfd52e2011-10-24 14:07:03 +0100326
327 /* Allocate pages for the queue - start with a queue as big as
328 * possible (limited by maximum size allowed by device), drop down
329 * to a minimal size, just big enough to fit descriptor table
330 * and two rings (which makes it "alignment_size * 2")
331 */
332 info->num = readl(vm_dev->base + VIRTIO_MMIO_QUEUE_NUM_MAX);
Brian Foleyd78b5192012-09-24 14:33:42 +0100333
334 /* If the device reports a 0 entry queue, we won't be able to
335 * use it to perform I/O, and vring_new_virtqueue() can't create
336 * empty queues anyway, so don't bother to set up the device.
337 */
338 if (info->num == 0) {
339 err = -ENOENT;
340 goto error_alloc_pages;
341 }
342
Pawel Molledfd52e2011-10-24 14:07:03 +0100343 while (1) {
344 size = PAGE_ALIGN(vring_size(info->num,
345 VIRTIO_MMIO_VRING_ALIGN));
Brian Foley3850d292012-09-24 14:33:41 +0100346 /* Did the last iter shrink the queue below minimum size? */
347 if (size < VIRTIO_MMIO_VRING_ALIGN * 2) {
Pawel Molledfd52e2011-10-24 14:07:03 +0100348 err = -ENOMEM;
349 goto error_alloc_pages;
350 }
351
352 info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
353 if (info->queue)
354 break;
355
356 info->num /= 2;
357 }
358
359 /* Activate the queue */
360 writel(info->num, vm_dev->base + VIRTIO_MMIO_QUEUE_NUM);
361 writel(VIRTIO_MMIO_VRING_ALIGN,
362 vm_dev->base + VIRTIO_MMIO_QUEUE_ALIGN);
363 writel(virt_to_phys(info->queue) >> PAGE_SHIFT,
364 vm_dev->base + VIRTIO_MMIO_QUEUE_PFN);
365
366 /* Create the vring */
Jason Wang17bb6d42012-08-28 13:54:13 +0200367 vq = vring_new_virtqueue(index, info->num, VIRTIO_MMIO_VRING_ALIGN, vdev,
Rusty Russell7b21e342012-01-12 15:44:42 +1030368 true, info->queue, vm_notify, callback, name);
Pawel Molledfd52e2011-10-24 14:07:03 +0100369 if (!vq) {
370 err = -ENOMEM;
371 goto error_new_virtqueue;
372 }
373
374 vq->priv = info;
375 info->vq = vq;
376
377 spin_lock_irqsave(&vm_dev->lock, flags);
378 list_add(&info->node, &vm_dev->virtqueues);
379 spin_unlock_irqrestore(&vm_dev->lock, flags);
380
381 return vq;
382
383error_new_virtqueue:
384 writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN);
385 free_pages_exact(info->queue, size);
386error_alloc_pages:
387 kfree(info);
388error_kmalloc:
389error_available:
390 return ERR_PTR(err);
391}
392
393static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
394 struct virtqueue *vqs[],
395 vq_callback_t *callbacks[],
396 const char *names[])
397{
398 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
399 unsigned int irq = platform_get_irq(vm_dev->pdev, 0);
400 int i, err;
401
402 err = request_irq(irq, vm_interrupt, IRQF_SHARED,
403 dev_name(&vdev->dev), vm_dev);
404 if (err)
405 return err;
406
407 for (i = 0; i < nvqs; ++i) {
408 vqs[i] = vm_setup_vq(vdev, i, callbacks[i], names[i]);
409 if (IS_ERR(vqs[i])) {
410 vm_del_vqs(vdev);
411 return PTR_ERR(vqs[i]);
412 }
413 }
414
415 return 0;
416}
417
Rick Jones66846042011-11-14 14:17:08 +0000418static const char *vm_bus_name(struct virtio_device *vdev)
419{
420 struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
Pawel Molledfd52e2011-10-24 14:07:03 +0100421
Rick Jones66846042011-11-14 14:17:08 +0000422 return vm_dev->pdev->name;
423}
Pawel Molledfd52e2011-10-24 14:07:03 +0100424
Stephen Hemminger93503932013-02-10 15:57:38 +1030425static const struct virtio_config_ops virtio_mmio_config_ops = {
Pawel Molledfd52e2011-10-24 14:07:03 +0100426 .get = vm_get,
427 .set = vm_set,
428 .get_status = vm_get_status,
429 .set_status = vm_set_status,
430 .reset = vm_reset,
431 .find_vqs = vm_find_vqs,
432 .del_vqs = vm_del_vqs,
433 .get_features = vm_get_features,
434 .finalize_features = vm_finalize_features,
Rick Jones66846042011-11-14 14:17:08 +0000435 .bus_name = vm_bus_name,
Pawel Molledfd52e2011-10-24 14:07:03 +0100436};
437
438
439
440/* Platform device */
441
Greg Kroah-Hartman8590dbc2012-12-21 13:05:30 -0800442static int virtio_mmio_probe(struct platform_device *pdev)
Pawel Molledfd52e2011-10-24 14:07:03 +0100443{
444 struct virtio_mmio_device *vm_dev;
445 struct resource *mem;
446 unsigned long magic;
447
448 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
449 if (!mem)
450 return -EINVAL;
451
452 if (!devm_request_mem_region(&pdev->dev, mem->start,
453 resource_size(mem), pdev->name))
454 return -EBUSY;
455
456 vm_dev = devm_kzalloc(&pdev->dev, sizeof(*vm_dev), GFP_KERNEL);
457 if (!vm_dev)
458 return -ENOMEM;
459
460 vm_dev->vdev.dev.parent = &pdev->dev;
461 vm_dev->vdev.config = &virtio_mmio_config_ops;
462 vm_dev->pdev = pdev;
463 INIT_LIST_HEAD(&vm_dev->virtqueues);
464 spin_lock_init(&vm_dev->lock);
465
466 vm_dev->base = devm_ioremap(&pdev->dev, mem->start, resource_size(mem));
467 if (vm_dev->base == NULL)
468 return -EFAULT;
469
470 /* Check magic value */
471 magic = readl(vm_dev->base + VIRTIO_MMIO_MAGIC_VALUE);
Marc Zyngier4ae85372013-11-05 21:21:28 +1030472 if (magic != ('v' | 'i' << 8 | 'r' << 16 | 't' << 24)) {
Pawel Molledfd52e2011-10-24 14:07:03 +0100473 dev_warn(&pdev->dev, "Wrong magic value 0x%08lx!\n", magic);
474 return -ENODEV;
475 }
476
477 /* Check device version */
478 vm_dev->version = readl(vm_dev->base + VIRTIO_MMIO_VERSION);
479 if (vm_dev->version != 1) {
480 dev_err(&pdev->dev, "Version %ld not supported!\n",
481 vm_dev->version);
482 return -ENXIO;
483 }
484
485 vm_dev->vdev.id.device = readl(vm_dev->base + VIRTIO_MMIO_DEVICE_ID);
486 vm_dev->vdev.id.vendor = readl(vm_dev->base + VIRTIO_MMIO_VENDOR_ID);
487
488 writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE);
489
490 platform_set_drvdata(pdev, vm_dev);
491
492 return register_virtio_device(&vm_dev->vdev);
493}
494
Greg Kroah-Hartman8590dbc2012-12-21 13:05:30 -0800495static int virtio_mmio_remove(struct platform_device *pdev)
Pawel Molledfd52e2011-10-24 14:07:03 +0100496{
497 struct virtio_mmio_device *vm_dev = platform_get_drvdata(pdev);
498
499 unregister_virtio_device(&vm_dev->vdev);
500
501 return 0;
502}
503
504
505
Pawel Moll81a054c2012-05-09 18:30:16 +0100506/* Devices list parameter */
507
508#if defined(CONFIG_VIRTIO_MMIO_CMDLINE_DEVICES)
509
510static struct device vm_cmdline_parent = {
511 .init_name = "virtio-mmio-cmdline",
512};
513
514static int vm_cmdline_parent_registered;
515static int vm_cmdline_id;
516
517static int vm_cmdline_set(const char *device,
518 const struct kernel_param *kp)
519{
520 int err;
521 struct resource resources[2] = {};
522 char *str;
Pawel Moll40f99382012-11-22 12:30:24 +1030523 long long int base, size;
524 unsigned int irq;
Pawel Moll81a054c2012-05-09 18:30:16 +0100525 int processed, consumed = 0;
526 struct platform_device *pdev;
527
Pawel Moll40f99382012-11-22 12:30:24 +1030528 /* Consume "size" part of the command line parameter */
529 size = memparse(device, &str);
Pawel Moll81a054c2012-05-09 18:30:16 +0100530
Pawel Moll40f99382012-11-22 12:30:24 +1030531 /* Get "@<base>:<irq>[:<id>]" chunks */
Pawel Moll81a054c2012-05-09 18:30:16 +0100532 processed = sscanf(str, "@%lli:%u%n:%d%n",
Pawel Moll40f99382012-11-22 12:30:24 +1030533 &base, &irq, &consumed,
Pawel Moll81a054c2012-05-09 18:30:16 +0100534 &vm_cmdline_id, &consumed);
535
Pawel Moll40f99382012-11-22 12:30:24 +1030536 /*
537 * sscanf() must processes at least 2 chunks; also there
538 * must be no extra characters after the last chunk, so
539 * str[consumed] must be '\0'
540 */
541 if (processed < 2 || str[consumed])
Pawel Moll81a054c2012-05-09 18:30:16 +0100542 return -EINVAL;
543
Pawel Moll40f99382012-11-22 12:30:24 +1030544 resources[0].flags = IORESOURCE_MEM;
Pawel Moll81a054c2012-05-09 18:30:16 +0100545 resources[0].start = base;
Pawel Moll40f99382012-11-22 12:30:24 +1030546 resources[0].end = base + size - 1;
547
548 resources[1].flags = IORESOURCE_IRQ;
549 resources[1].start = resources[1].end = irq;
Pawel Moll81a054c2012-05-09 18:30:16 +0100550
551 if (!vm_cmdline_parent_registered) {
552 err = device_register(&vm_cmdline_parent);
553 if (err) {
554 pr_err("Failed to register parent device!\n");
555 return err;
556 }
557 vm_cmdline_parent_registered = 1;
558 }
559
560 pr_info("Registering device virtio-mmio.%d at 0x%llx-0x%llx, IRQ %d.\n",
561 vm_cmdline_id,
562 (unsigned long long)resources[0].start,
563 (unsigned long long)resources[0].end,
564 (int)resources[1].start);
565
566 pdev = platform_device_register_resndata(&vm_cmdline_parent,
567 "virtio-mmio", vm_cmdline_id++,
568 resources, ARRAY_SIZE(resources), NULL, 0);
569 if (IS_ERR(pdev))
570 return PTR_ERR(pdev);
571
572 return 0;
573}
574
575static int vm_cmdline_get_device(struct device *dev, void *data)
576{
577 char *buffer = data;
578 unsigned int len = strlen(buffer);
579 struct platform_device *pdev = to_platform_device(dev);
580
581 snprintf(buffer + len, PAGE_SIZE - len, "0x%llx@0x%llx:%llu:%d\n",
582 pdev->resource[0].end - pdev->resource[0].start + 1ULL,
583 (unsigned long long)pdev->resource[0].start,
584 (unsigned long long)pdev->resource[1].start,
585 pdev->id);
586 return 0;
587}
588
589static int vm_cmdline_get(char *buffer, const struct kernel_param *kp)
590{
591 buffer[0] = '\0';
592 device_for_each_child(&vm_cmdline_parent, buffer,
593 vm_cmdline_get_device);
594 return strlen(buffer) + 1;
595}
596
597static struct kernel_param_ops vm_cmdline_param_ops = {
598 .set = vm_cmdline_set,
599 .get = vm_cmdline_get,
600};
601
602device_param_cb(device, &vm_cmdline_param_ops, NULL, S_IRUSR);
603
604static int vm_unregister_cmdline_device(struct device *dev,
605 void *data)
606{
607 platform_device_unregister(to_platform_device(dev));
608
609 return 0;
610}
611
612static void vm_unregister_cmdline_devices(void)
613{
614 if (vm_cmdline_parent_registered) {
615 device_for_each_child(&vm_cmdline_parent, NULL,
616 vm_unregister_cmdline_device);
617 device_unregister(&vm_cmdline_parent);
618 vm_cmdline_parent_registered = 0;
619 }
620}
621
622#else
623
624static void vm_unregister_cmdline_devices(void)
625{
626}
627
628#endif
629
Pawel Molledfd52e2011-10-24 14:07:03 +0100630/* Platform driver */
631
632static struct of_device_id virtio_mmio_match[] = {
633 { .compatible = "virtio,mmio", },
634 {},
635};
636MODULE_DEVICE_TABLE(of, virtio_mmio_match);
637
638static struct platform_driver virtio_mmio_driver = {
639 .probe = virtio_mmio_probe,
Greg Kroah-Hartman8590dbc2012-12-21 13:05:30 -0800640 .remove = virtio_mmio_remove,
Pawel Molledfd52e2011-10-24 14:07:03 +0100641 .driver = {
642 .name = "virtio-mmio",
Pawel Molledfd52e2011-10-24 14:07:03 +0100643 .of_match_table = virtio_mmio_match,
644 },
645};
646
647static int __init virtio_mmio_init(void)
648{
649 return platform_driver_register(&virtio_mmio_driver);
650}
651
652static void __exit virtio_mmio_exit(void)
653{
654 platform_driver_unregister(&virtio_mmio_driver);
Pawel Moll81a054c2012-05-09 18:30:16 +0100655 vm_unregister_cmdline_devices();
Pawel Molledfd52e2011-10-24 14:07:03 +0100656}
657
658module_init(virtio_mmio_init);
659module_exit(virtio_mmio_exit);
660
661MODULE_AUTHOR("Pawel Moll <pawel.moll@arm.com>");
662MODULE_DESCRIPTION("Platform bus driver for memory mapped virtio devices");
663MODULE_LICENSE("GPL");