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1/*
2 * linux/arch/arm/common/amba.c
3 *
4 * Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/device.h>
13#include <linux/string.h>
14#include <linux/slab.h>
15#include <linux/io.h>
16#include <linux/pm.h>
17#include <linux/pm_runtime.h>
18#include <linux/amba/bus.h>
19
20#include <asm/irq.h>
21#include <asm/sizes.h>
22
23#define to_amba_driver(d) container_of(d, struct amba_driver, drv)
24
25static const struct amba_id *
26amba_lookup(const struct amba_id *table, struct amba_device *dev)
27{
28 int ret = 0;
29
30 while (table->mask) {
31 ret = (dev->periphid & table->mask) == table->id;
32 if (ret)
33 break;
34 table++;
35 }
36
37 return ret ? table : NULL;
38}
39
40static int amba_match(struct device *dev, struct device_driver *drv)
41{
42 struct amba_device *pcdev = to_amba_device(dev);
43 struct amba_driver *pcdrv = to_amba_driver(drv);
44
45 return amba_lookup(pcdrv->id_table, pcdev) != NULL;
46}
47
48#ifdef CONFIG_HOTPLUG
49static int amba_uevent(struct device *dev, struct kobj_uevent_env *env)
50{
51 struct amba_device *pcdev = to_amba_device(dev);
52 int retval = 0;
53
54 retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid);
55 return retval;
56}
57#else
58#define amba_uevent NULL
59#endif
60
61#define amba_attr_func(name,fmt,arg...) \
62static ssize_t name##_show(struct device *_dev, \
63 struct device_attribute *attr, char *buf) \
64{ \
65 struct amba_device *dev = to_amba_device(_dev); \
66 return sprintf(buf, fmt, arg); \
67}
68
69#define amba_attr(name,fmt,arg...) \
70amba_attr_func(name,fmt,arg) \
71static DEVICE_ATTR(name, S_IRUGO, name##_show, NULL)
72
73amba_attr_func(id, "%08x\n", dev->periphid);
74amba_attr(irq0, "%u\n", dev->irq[0]);
75amba_attr(irq1, "%u\n", dev->irq[1]);
76amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n",
77 (unsigned long long)dev->res.start, (unsigned long long)dev->res.end,
78 dev->res.flags);
79
80static struct device_attribute amba_dev_attrs[] = {
81 __ATTR_RO(id),
82 __ATTR_RO(resource),
83 __ATTR_NULL,
84};
85
86#ifdef CONFIG_PM_SLEEP
87
88static int amba_legacy_suspend(struct device *dev, pm_message_t mesg)
89{
90 struct amba_driver *adrv = to_amba_driver(dev->driver);
91 struct amba_device *adev = to_amba_device(dev);
92 int ret = 0;
93
94 if (dev->driver && adrv->suspend)
95 ret = adrv->suspend(adev, mesg);
96
97 return ret;
98}
99
100static int amba_legacy_resume(struct device *dev)
101{
102 struct amba_driver *adrv = to_amba_driver(dev->driver);
103 struct amba_device *adev = to_amba_device(dev);
104 int ret = 0;
105
106 if (dev->driver && adrv->resume)
107 ret = adrv->resume(adev);
108
109 return ret;
110}
111
112static int amba_pm_prepare(struct device *dev)
113{
114 struct device_driver *drv = dev->driver;
115 int ret = 0;
116
117 if (drv && drv->pm && drv->pm->prepare)
118 ret = drv->pm->prepare(dev);
119
120 return ret;
121}
122
123static void amba_pm_complete(struct device *dev)
124{
125 struct device_driver *drv = dev->driver;
126
127 if (drv && drv->pm && drv->pm->complete)
128 drv->pm->complete(dev);
129}
130
131#else /* !CONFIG_PM_SLEEP */
132
133#define amba_pm_prepare NULL
134#define amba_pm_complete NULL
135
136#endif /* !CONFIG_PM_SLEEP */
137
138#ifdef CONFIG_SUSPEND
139
140static int amba_pm_suspend(struct device *dev)
141{
142 struct device_driver *drv = dev->driver;
143 int ret = 0;
144
145 if (!drv)
146 return 0;
147
148 if (drv->pm) {
149 if (drv->pm->suspend)
150 ret = drv->pm->suspend(dev);
151 } else {
152 ret = amba_legacy_suspend(dev, PMSG_SUSPEND);
153 }
154
155 return ret;
156}
157
158static int amba_pm_suspend_noirq(struct device *dev)
159{
160 struct device_driver *drv = dev->driver;
161 int ret = 0;
162
163 if (!drv)
164 return 0;
165
166 if (drv->pm) {
167 if (drv->pm->suspend_noirq)
168 ret = drv->pm->suspend_noirq(dev);
169 }
170
171 return ret;
172}
173
174static int amba_pm_resume(struct device *dev)
175{
176 struct device_driver *drv = dev->driver;
177 int ret = 0;
178
179 if (!drv)
180 return 0;
181
182 if (drv->pm) {
183 if (drv->pm->resume)
184 ret = drv->pm->resume(dev);
185 } else {
186 ret = amba_legacy_resume(dev);
187 }
188
189 return ret;
190}
191
192static int amba_pm_resume_noirq(struct device *dev)
193{
194 struct device_driver *drv = dev->driver;
195 int ret = 0;
196
197 if (!drv)
198 return 0;
199
200 if (drv->pm) {
201 if (drv->pm->resume_noirq)
202 ret = drv->pm->resume_noirq(dev);
203 }
204
205 return ret;
206}
207
208#else /* !CONFIG_SUSPEND */
209
210#define amba_pm_suspend NULL
211#define amba_pm_resume NULL
212#define amba_pm_suspend_noirq NULL
213#define amba_pm_resume_noirq NULL
214
215#endif /* !CONFIG_SUSPEND */
216
217#ifdef CONFIG_HIBERNATE_CALLBACKS
218
219static int amba_pm_freeze(struct device *dev)
220{
221 struct device_driver *drv = dev->driver;
222 int ret = 0;
223
224 if (!drv)
225 return 0;
226
227 if (drv->pm) {
228 if (drv->pm->freeze)
229 ret = drv->pm->freeze(dev);
230 } else {
231 ret = amba_legacy_suspend(dev, PMSG_FREEZE);
232 }
233
234 return ret;
235}
236
237static int amba_pm_freeze_noirq(struct device *dev)
238{
239 struct device_driver *drv = dev->driver;
240 int ret = 0;
241
242 if (!drv)
243 return 0;
244
245 if (drv->pm) {
246 if (drv->pm->freeze_noirq)
247 ret = drv->pm->freeze_noirq(dev);
248 }
249
250 return ret;
251}
252
253static int amba_pm_thaw(struct device *dev)
254{
255 struct device_driver *drv = dev->driver;
256 int ret = 0;
257
258 if (!drv)
259 return 0;
260
261 if (drv->pm) {
262 if (drv->pm->thaw)
263 ret = drv->pm->thaw(dev);
264 } else {
265 ret = amba_legacy_resume(dev);
266 }
267
268 return ret;
269}
270
271static int amba_pm_thaw_noirq(struct device *dev)
272{
273 struct device_driver *drv = dev->driver;
274 int ret = 0;
275
276 if (!drv)
277 return 0;
278
279 if (drv->pm) {
280 if (drv->pm->thaw_noirq)
281 ret = drv->pm->thaw_noirq(dev);
282 }
283
284 return ret;
285}
286
287static int amba_pm_poweroff(struct device *dev)
288{
289 struct device_driver *drv = dev->driver;
290 int ret = 0;
291
292 if (!drv)
293 return 0;
294
295 if (drv->pm) {
296 if (drv->pm->poweroff)
297 ret = drv->pm->poweroff(dev);
298 } else {
299 ret = amba_legacy_suspend(dev, PMSG_HIBERNATE);
300 }
301
302 return ret;
303}
304
305static int amba_pm_poweroff_noirq(struct device *dev)
306{
307 struct device_driver *drv = dev->driver;
308 int ret = 0;
309
310 if (!drv)
311 return 0;
312
313 if (drv->pm) {
314 if (drv->pm->poweroff_noirq)
315 ret = drv->pm->poweroff_noirq(dev);
316 }
317
318 return ret;
319}
320
321static int amba_pm_restore(struct device *dev)
322{
323 struct device_driver *drv = dev->driver;
324 int ret = 0;
325
326 if (!drv)
327 return 0;
328
329 if (drv->pm) {
330 if (drv->pm->restore)
331 ret = drv->pm->restore(dev);
332 } else {
333 ret = amba_legacy_resume(dev);
334 }
335
336 return ret;
337}
338
339static int amba_pm_restore_noirq(struct device *dev)
340{
341 struct device_driver *drv = dev->driver;
342 int ret = 0;
343
344 if (!drv)
345 return 0;
346
347 if (drv->pm) {
348 if (drv->pm->restore_noirq)
349 ret = drv->pm->restore_noirq(dev);
350 }
351
352 return ret;
353}
354
355#else /* !CONFIG_HIBERNATE_CALLBACKS */
356
357#define amba_pm_freeze NULL
358#define amba_pm_thaw NULL
359#define amba_pm_poweroff NULL
360#define amba_pm_restore NULL
361#define amba_pm_freeze_noirq NULL
362#define amba_pm_thaw_noirq NULL
363#define amba_pm_poweroff_noirq NULL
364#define amba_pm_restore_noirq NULL
365
366#endif /* !CONFIG_HIBERNATE_CALLBACKS */
367
368#ifdef CONFIG_PM
369
370static const struct dev_pm_ops amba_pm = {
371 .prepare = amba_pm_prepare,
372 .complete = amba_pm_complete,
373 .suspend = amba_pm_suspend,
374 .resume = amba_pm_resume,
375 .freeze = amba_pm_freeze,
376 .thaw = amba_pm_thaw,
377 .poweroff = amba_pm_poweroff,
378 .restore = amba_pm_restore,
379 .suspend_noirq = amba_pm_suspend_noirq,
380 .resume_noirq = amba_pm_resume_noirq,
381 .freeze_noirq = amba_pm_freeze_noirq,
382 .thaw_noirq = amba_pm_thaw_noirq,
383 .poweroff_noirq = amba_pm_poweroff_noirq,
384 .restore_noirq = amba_pm_restore_noirq,
385 SET_RUNTIME_PM_OPS(
386 pm_generic_runtime_suspend,
387 pm_generic_runtime_resume,
388 pm_generic_runtime_idle
389 )
390};
391
392#define AMBA_PM (&amba_pm)
393
394#else /* !CONFIG_PM */
395
396#define AMBA_PM NULL
397
398#endif /* !CONFIG_PM */
399
400/*
401 * Primecells are part of the Advanced Microcontroller Bus Architecture,
402 * so we call the bus "amba".
403 */
404struct bus_type amba_bustype = {
405 .name = "amba",
406 .dev_attrs = amba_dev_attrs,
407 .match = amba_match,
408 .uevent = amba_uevent,
409 .pm = AMBA_PM,
410};
411
412static int __init amba_init(void)
413{
414 return bus_register(&amba_bustype);
415}
416
417postcore_initcall(amba_init);
418
419static int amba_get_enable_pclk(struct amba_device *pcdev)
420{
421 struct clk *pclk = clk_get(&pcdev->dev, "apb_pclk");
422 int ret;
423
424 pcdev->pclk = pclk;
425
426 if (IS_ERR(pclk))
427 return PTR_ERR(pclk);
428
429 ret = clk_enable(pclk);
430 if (ret)
431 clk_put(pclk);
432
433 return ret;
434}
435
436static void amba_put_disable_pclk(struct amba_device *pcdev)
437{
438 struct clk *pclk = pcdev->pclk;
439
440 clk_disable(pclk);
441 clk_put(pclk);
442}
443
444static int amba_get_enable_vcore(struct amba_device *pcdev)
445{
446 struct regulator *vcore = regulator_get(&pcdev->dev, "vcore");
447 int ret;
448
449 pcdev->vcore = vcore;
450
451 if (IS_ERR(vcore)) {
452 /* It is OK not to supply a vcore regulator */
453 if (PTR_ERR(vcore) == -ENODEV)
454 return 0;
455 return PTR_ERR(vcore);
456 }
457
458 ret = regulator_enable(vcore);
459 if (ret) {
460 regulator_put(vcore);
461 pcdev->vcore = ERR_PTR(-ENODEV);
462 }
463
464 return ret;
465}
466
467static void amba_put_disable_vcore(struct amba_device *pcdev)
468{
469 struct regulator *vcore = pcdev->vcore;
470
471 if (!IS_ERR(vcore)) {
472 regulator_disable(vcore);
473 regulator_put(vcore);
474 }
475}
476
477/*
478 * These are the device model conversion veneers; they convert the
479 * device model structures to our more specific structures.
480 */
481static int amba_probe(struct device *dev)
482{
483 struct amba_device *pcdev = to_amba_device(dev);
484 struct amba_driver *pcdrv = to_amba_driver(dev->driver);
485 const struct amba_id *id = amba_lookup(pcdrv->id_table, pcdev);
486 int ret;
487
488 do {
489 ret = amba_get_enable_vcore(pcdev);
490 if (ret)
491 break;
492
493 ret = amba_get_enable_pclk(pcdev);
494 if (ret)
495 break;
496
497 ret = pcdrv->probe(pcdev, id);
498 if (ret == 0)
499 break;
500
501 amba_put_disable_pclk(pcdev);
502 amba_put_disable_vcore(pcdev);
503 } while (0);
504
505 return ret;
506}
507
508static int amba_remove(struct device *dev)
509{
510 struct amba_device *pcdev = to_amba_device(dev);
511 struct amba_driver *drv = to_amba_driver(dev->driver);
512 int ret = drv->remove(pcdev);
513
514 amba_put_disable_pclk(pcdev);
515 amba_put_disable_vcore(pcdev);
516
517 return ret;
518}
519
520static void amba_shutdown(struct device *dev)
521{
522 struct amba_driver *drv = to_amba_driver(dev->driver);
523 drv->shutdown(to_amba_device(dev));
524}
525
526/**
527 * amba_driver_register - register an AMBA device driver
528 * @drv: amba device driver structure
529 *
530 * Register an AMBA device driver with the Linux device model
531 * core. If devices pre-exist, the drivers probe function will
532 * be called.
533 */
534int amba_driver_register(struct amba_driver *drv)
535{
536 drv->drv.bus = &amba_bustype;
537
538#define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
539 SETFN(probe);
540 SETFN(remove);
541 SETFN(shutdown);
542
543 return driver_register(&drv->drv);
544}
545
546/**
547 * amba_driver_unregister - remove an AMBA device driver
548 * @drv: AMBA device driver structure to remove
549 *
550 * Unregister an AMBA device driver from the Linux device
551 * model. The device model will call the drivers remove function
552 * for each device the device driver is currently handling.
553 */
554void amba_driver_unregister(struct amba_driver *drv)
555{
556 driver_unregister(&drv->drv);
557}
558
559
560static void amba_device_release(struct device *dev)
561{
562 struct amba_device *d = to_amba_device(dev);
563
564 if (d->res.parent)
565 release_resource(&d->res);
566 kfree(d);
567}
568
569/**
570 * amba_device_register - register an AMBA device
571 * @dev: AMBA device to register
572 * @parent: parent memory resource
573 *
574 * Setup the AMBA device, reading the cell ID if present.
575 * Claim the resource, and register the AMBA device with
576 * the Linux device manager.
577 */
578int amba_device_register(struct amba_device *dev, struct resource *parent)
579{
580 u32 size;
581 void __iomem *tmp;
582 int i, ret;
583
584 device_initialize(&dev->dev);
585
586 /*
587 * Copy from device_add
588 */
589 if (dev->dev.init_name) {
590 dev_set_name(&dev->dev, "%s", dev->dev.init_name);
591 dev->dev.init_name = NULL;
592 }
593
594 dev->dev.release = amba_device_release;
595 dev->dev.bus = &amba_bustype;
596 dev->dev.dma_mask = &dev->dma_mask;
597 dev->res.name = dev_name(&dev->dev);
598
599 if (!dev->dev.coherent_dma_mask && dev->dma_mask)
600 dev_warn(&dev->dev, "coherent dma mask is unset\n");
601
602 ret = request_resource(parent, &dev->res);
603 if (ret)
604 goto err_out;
605
606 /* Hard-coded primecell ID instead of plug-n-play */
607 if (dev->periphid != 0)
608 goto skip_probe;
609
610 /*
611 * Dynamically calculate the size of the resource
612 * and use this for iomap
613 */
614 size = resource_size(&dev->res);
615 tmp = ioremap(dev->res.start, size);
616 if (!tmp) {
617 ret = -ENOMEM;
618 goto err_release;
619 }
620
621 ret = amba_get_enable_pclk(dev);
622 if (ret == 0) {
623 u32 pid, cid;
624
625 /*
626 * Read pid and cid based on size of resource
627 * they are located at end of region
628 */
629 for (pid = 0, i = 0; i < 4; i++)
630 pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) <<
631 (i * 8);
632 for (cid = 0, i = 0; i < 4; i++)
633 cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) <<
634 (i * 8);
635
636 amba_put_disable_pclk(dev);
637
638 if (cid == AMBA_CID)
639 dev->periphid = pid;
640
641 if (!dev->periphid)
642 ret = -ENODEV;
643 }
644
645 iounmap(tmp);
646
647 if (ret)
648 goto err_release;
649
650 skip_probe:
651 ret = device_add(&dev->dev);
652 if (ret)
653 goto err_release;
654
655 if (dev->irq[0] != NO_IRQ)
656 ret = device_create_file(&dev->dev, &dev_attr_irq0);
657 if (ret == 0 && dev->irq[1] != NO_IRQ)
658 ret = device_create_file(&dev->dev, &dev_attr_irq1);
659 if (ret == 0)
660 return ret;
661
662 device_unregister(&dev->dev);
663
664 err_release:
665 release_resource(&dev->res);
666 err_out:
667 return ret;
668}
669
670/**
671 * amba_device_unregister - unregister an AMBA device
672 * @dev: AMBA device to remove
673 *
674 * Remove the specified AMBA device from the Linux device
675 * manager. All files associated with this object will be
676 * destroyed, and device drivers notified that the device has
677 * been removed. The AMBA device's resources including
678 * the amba_device structure will be freed once all
679 * references to it have been dropped.
680 */
681void amba_device_unregister(struct amba_device *dev)
682{
683 device_unregister(&dev->dev);
684}
685
686
687struct find_data {
688 struct amba_device *dev;
689 struct device *parent;
690 const char *busid;
691 unsigned int id;
692 unsigned int mask;
693};
694
695static int amba_find_match(struct device *dev, void *data)
696{
697 struct find_data *d = data;
698 struct amba_device *pcdev = to_amba_device(dev);
699 int r;
700
701 r = (pcdev->periphid & d->mask) == d->id;
702 if (d->parent)
703 r &= d->parent == dev->parent;
704 if (d->busid)
705 r &= strcmp(dev_name(dev), d->busid) == 0;
706
707 if (r) {
708 get_device(dev);
709 d->dev = pcdev;
710 }
711
712 return r;
713}
714
715/**
716 * amba_find_device - locate an AMBA device given a bus id
717 * @busid: bus id for device (or NULL)
718 * @parent: parent device (or NULL)
719 * @id: peripheral ID (or 0)
720 * @mask: peripheral ID mask (or 0)
721 *
722 * Return the AMBA device corresponding to the supplied parameters.
723 * If no device matches, returns NULL.
724 *
725 * NOTE: When a valid device is found, its refcount is
726 * incremented, and must be decremented before the returned
727 * reference.
728 */
729struct amba_device *
730amba_find_device(const char *busid, struct device *parent, unsigned int id,
731 unsigned int mask)
732{
733 struct find_data data;
734
735 data.dev = NULL;
736 data.parent = parent;
737 data.busid = busid;
738 data.id = id;
739 data.mask = mask;
740
741 bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
742
743 return data.dev;
744}
745
746/**
747 * amba_request_regions - request all mem regions associated with device
748 * @dev: amba_device structure for device
749 * @name: name, or NULL to use driver name
750 */
751int amba_request_regions(struct amba_device *dev, const char *name)
752{
753 int ret = 0;
754 u32 size;
755
756 if (!name)
757 name = dev->dev.driver->name;
758
759 size = resource_size(&dev->res);
760
761 if (!request_mem_region(dev->res.start, size, name))
762 ret = -EBUSY;
763
764 return ret;
765}
766
767/**
768 * amba_release_regions - release mem regions associated with device
769 * @dev: amba_device structure for device
770 *
771 * Release regions claimed by a successful call to amba_request_regions.
772 */
773void amba_release_regions(struct amba_device *dev)
774{
775 u32 size;
776
777 size = resource_size(&dev->res);
778 release_mem_region(dev->res.start, size);
779}
780
781EXPORT_SYMBOL(amba_driver_register);
782EXPORT_SYMBOL(amba_driver_unregister);
783EXPORT_SYMBOL(amba_device_register);
784EXPORT_SYMBOL(amba_device_unregister);
785EXPORT_SYMBOL(amba_find_device);
786EXPORT_SYMBOL(amba_request_regions);
787EXPORT_SYMBOL(amba_release_regions);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/common/amba.c
4 *
5 * Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
6 */
7#include <linux/module.h>
8#include <linux/init.h>
9#include <linux/device.h>
10#include <linux/string.h>
11#include <linux/slab.h>
12#include <linux/io.h>
13#include <linux/pm.h>
14#include <linux/pm_runtime.h>
15#include <linux/pm_domain.h>
16#include <linux/amba/bus.h>
17#include <linux/sizes.h>
18#include <linux/limits.h>
19#include <linux/clk/clk-conf.h>
20#include <linux/platform_device.h>
21#include <linux/reset.h>
22
23#include <asm/irq.h>
24
25#define to_amba_driver(d) container_of(d, struct amba_driver, drv)
26
27/* called on periphid match and class 0x9 coresight device. */
28static int
29amba_cs_uci_id_match(const struct amba_id *table, struct amba_device *dev)
30{
31 int ret = 0;
32 struct amba_cs_uci_id *uci;
33
34 uci = table->data;
35
36 /* no table data or zero mask - return match on periphid */
37 if (!uci || (uci->devarch_mask == 0))
38 return 1;
39
40 /* test against read devtype and masked devarch value */
41 ret = (dev->uci.devtype == uci->devtype) &&
42 ((dev->uci.devarch & uci->devarch_mask) == uci->devarch);
43 return ret;
44}
45
46static const struct amba_id *
47amba_lookup(const struct amba_id *table, struct amba_device *dev)
48{
49 while (table->mask) {
50 if (((dev->periphid & table->mask) == table->id) &&
51 ((dev->cid != CORESIGHT_CID) ||
52 (amba_cs_uci_id_match(table, dev))))
53 return table;
54 table++;
55 }
56 return NULL;
57}
58
59static int amba_match(struct device *dev, struct device_driver *drv)
60{
61 struct amba_device *pcdev = to_amba_device(dev);
62 struct amba_driver *pcdrv = to_amba_driver(drv);
63
64 /* When driver_override is set, only bind to the matching driver */
65 if (pcdev->driver_override)
66 return !strcmp(pcdev->driver_override, drv->name);
67
68 return amba_lookup(pcdrv->id_table, pcdev) != NULL;
69}
70
71static int amba_uevent(struct device *dev, struct kobj_uevent_env *env)
72{
73 struct amba_device *pcdev = to_amba_device(dev);
74 int retval = 0;
75
76 retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid);
77 if (retval)
78 return retval;
79
80 retval = add_uevent_var(env, "MODALIAS=amba:d%08X", pcdev->periphid);
81 return retval;
82}
83
84static ssize_t driver_override_show(struct device *_dev,
85 struct device_attribute *attr, char *buf)
86{
87 struct amba_device *dev = to_amba_device(_dev);
88 ssize_t len;
89
90 device_lock(_dev);
91 len = sprintf(buf, "%s\n", dev->driver_override);
92 device_unlock(_dev);
93 return len;
94}
95
96static ssize_t driver_override_store(struct device *_dev,
97 struct device_attribute *attr,
98 const char *buf, size_t count)
99{
100 struct amba_device *dev = to_amba_device(_dev);
101 char *driver_override, *old, *cp;
102
103 /* We need to keep extra room for a newline */
104 if (count >= (PAGE_SIZE - 1))
105 return -EINVAL;
106
107 driver_override = kstrndup(buf, count, GFP_KERNEL);
108 if (!driver_override)
109 return -ENOMEM;
110
111 cp = strchr(driver_override, '\n');
112 if (cp)
113 *cp = '\0';
114
115 device_lock(_dev);
116 old = dev->driver_override;
117 if (strlen(driver_override)) {
118 dev->driver_override = driver_override;
119 } else {
120 kfree(driver_override);
121 dev->driver_override = NULL;
122 }
123 device_unlock(_dev);
124
125 kfree(old);
126
127 return count;
128}
129static DEVICE_ATTR_RW(driver_override);
130
131#define amba_attr_func(name,fmt,arg...) \
132static ssize_t name##_show(struct device *_dev, \
133 struct device_attribute *attr, char *buf) \
134{ \
135 struct amba_device *dev = to_amba_device(_dev); \
136 return sprintf(buf, fmt, arg); \
137} \
138static DEVICE_ATTR_RO(name)
139
140amba_attr_func(id, "%08x\n", dev->periphid);
141amba_attr_func(irq0, "%u\n", dev->irq[0]);
142amba_attr_func(irq1, "%u\n", dev->irq[1]);
143amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n",
144 (unsigned long long)dev->res.start, (unsigned long long)dev->res.end,
145 dev->res.flags);
146
147static struct attribute *amba_dev_attrs[] = {
148 &dev_attr_id.attr,
149 &dev_attr_resource.attr,
150 &dev_attr_driver_override.attr,
151 NULL,
152};
153ATTRIBUTE_GROUPS(amba_dev);
154
155#ifdef CONFIG_PM
156/*
157 * Hooks to provide runtime PM of the pclk (bus clock). It is safe to
158 * enable/disable the bus clock at runtime PM suspend/resume as this
159 * does not result in loss of context.
160 */
161static int amba_pm_runtime_suspend(struct device *dev)
162{
163 struct amba_device *pcdev = to_amba_device(dev);
164 int ret = pm_generic_runtime_suspend(dev);
165
166 if (ret == 0 && dev->driver) {
167 if (pm_runtime_is_irq_safe(dev))
168 clk_disable(pcdev->pclk);
169 else
170 clk_disable_unprepare(pcdev->pclk);
171 }
172
173 return ret;
174}
175
176static int amba_pm_runtime_resume(struct device *dev)
177{
178 struct amba_device *pcdev = to_amba_device(dev);
179 int ret;
180
181 if (dev->driver) {
182 if (pm_runtime_is_irq_safe(dev))
183 ret = clk_enable(pcdev->pclk);
184 else
185 ret = clk_prepare_enable(pcdev->pclk);
186 /* Failure is probably fatal to the system, but... */
187 if (ret)
188 return ret;
189 }
190
191 return pm_generic_runtime_resume(dev);
192}
193#endif /* CONFIG_PM */
194
195static const struct dev_pm_ops amba_pm = {
196 .suspend = pm_generic_suspend,
197 .resume = pm_generic_resume,
198 .freeze = pm_generic_freeze,
199 .thaw = pm_generic_thaw,
200 .poweroff = pm_generic_poweroff,
201 .restore = pm_generic_restore,
202 SET_RUNTIME_PM_OPS(
203 amba_pm_runtime_suspend,
204 amba_pm_runtime_resume,
205 NULL
206 )
207};
208
209/*
210 * Primecells are part of the Advanced Microcontroller Bus Architecture,
211 * so we call the bus "amba".
212 * DMA configuration for platform and AMBA bus is same. So here we reuse
213 * platform's DMA config routine.
214 */
215struct bus_type amba_bustype = {
216 .name = "amba",
217 .dev_groups = amba_dev_groups,
218 .match = amba_match,
219 .uevent = amba_uevent,
220 .dma_configure = platform_dma_configure,
221 .pm = &amba_pm,
222};
223EXPORT_SYMBOL_GPL(amba_bustype);
224
225static int __init amba_init(void)
226{
227 return bus_register(&amba_bustype);
228}
229
230postcore_initcall(amba_init);
231
232static int amba_get_enable_pclk(struct amba_device *pcdev)
233{
234 int ret;
235
236 pcdev->pclk = clk_get(&pcdev->dev, "apb_pclk");
237 if (IS_ERR(pcdev->pclk))
238 return PTR_ERR(pcdev->pclk);
239
240 ret = clk_prepare_enable(pcdev->pclk);
241 if (ret)
242 clk_put(pcdev->pclk);
243
244 return ret;
245}
246
247static void amba_put_disable_pclk(struct amba_device *pcdev)
248{
249 clk_disable_unprepare(pcdev->pclk);
250 clk_put(pcdev->pclk);
251}
252
253/*
254 * These are the device model conversion veneers; they convert the
255 * device model structures to our more specific structures.
256 */
257static int amba_probe(struct device *dev)
258{
259 struct amba_device *pcdev = to_amba_device(dev);
260 struct amba_driver *pcdrv = to_amba_driver(dev->driver);
261 const struct amba_id *id = amba_lookup(pcdrv->id_table, pcdev);
262 int ret;
263
264 do {
265 ret = of_clk_set_defaults(dev->of_node, false);
266 if (ret < 0)
267 break;
268
269 ret = dev_pm_domain_attach(dev, true);
270 if (ret)
271 break;
272
273 ret = amba_get_enable_pclk(pcdev);
274 if (ret) {
275 dev_pm_domain_detach(dev, true);
276 break;
277 }
278
279 pm_runtime_get_noresume(dev);
280 pm_runtime_set_active(dev);
281 pm_runtime_enable(dev);
282
283 ret = pcdrv->probe(pcdev, id);
284 if (ret == 0)
285 break;
286
287 pm_runtime_disable(dev);
288 pm_runtime_set_suspended(dev);
289 pm_runtime_put_noidle(dev);
290
291 amba_put_disable_pclk(pcdev);
292 dev_pm_domain_detach(dev, true);
293 } while (0);
294
295 return ret;
296}
297
298static int amba_remove(struct device *dev)
299{
300 struct amba_device *pcdev = to_amba_device(dev);
301 struct amba_driver *drv = to_amba_driver(dev->driver);
302 int ret;
303
304 pm_runtime_get_sync(dev);
305 ret = drv->remove(pcdev);
306 pm_runtime_put_noidle(dev);
307
308 /* Undo the runtime PM settings in amba_probe() */
309 pm_runtime_disable(dev);
310 pm_runtime_set_suspended(dev);
311 pm_runtime_put_noidle(dev);
312
313 amba_put_disable_pclk(pcdev);
314 dev_pm_domain_detach(dev, true);
315
316 return ret;
317}
318
319static void amba_shutdown(struct device *dev)
320{
321 struct amba_driver *drv = to_amba_driver(dev->driver);
322 drv->shutdown(to_amba_device(dev));
323}
324
325/**
326 * amba_driver_register - register an AMBA device driver
327 * @drv: amba device driver structure
328 *
329 * Register an AMBA device driver with the Linux device model
330 * core. If devices pre-exist, the drivers probe function will
331 * be called.
332 */
333int amba_driver_register(struct amba_driver *drv)
334{
335 drv->drv.bus = &amba_bustype;
336
337#define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
338 SETFN(probe);
339 SETFN(remove);
340 SETFN(shutdown);
341
342 return driver_register(&drv->drv);
343}
344
345/**
346 * amba_driver_unregister - remove an AMBA device driver
347 * @drv: AMBA device driver structure to remove
348 *
349 * Unregister an AMBA device driver from the Linux device
350 * model. The device model will call the drivers remove function
351 * for each device the device driver is currently handling.
352 */
353void amba_driver_unregister(struct amba_driver *drv)
354{
355 driver_unregister(&drv->drv);
356}
357
358
359static void amba_device_release(struct device *dev)
360{
361 struct amba_device *d = to_amba_device(dev);
362
363 if (d->res.parent)
364 release_resource(&d->res);
365 kfree(d);
366}
367
368static int amba_device_try_add(struct amba_device *dev, struct resource *parent)
369{
370 u32 size;
371 void __iomem *tmp;
372 int i, ret;
373
374 WARN_ON(dev->irq[0] == (unsigned int)-1);
375 WARN_ON(dev->irq[1] == (unsigned int)-1);
376
377 ret = request_resource(parent, &dev->res);
378 if (ret)
379 goto err_out;
380
381 /* Hard-coded primecell ID instead of plug-n-play */
382 if (dev->periphid != 0)
383 goto skip_probe;
384
385 /*
386 * Dynamically calculate the size of the resource
387 * and use this for iomap
388 */
389 size = resource_size(&dev->res);
390 tmp = ioremap(dev->res.start, size);
391 if (!tmp) {
392 ret = -ENOMEM;
393 goto err_release;
394 }
395
396 ret = dev_pm_domain_attach(&dev->dev, true);
397 if (ret) {
398 iounmap(tmp);
399 goto err_release;
400 }
401
402 ret = amba_get_enable_pclk(dev);
403 if (ret == 0) {
404 u32 pid, cid;
405 struct reset_control *rstc;
406
407 /*
408 * Find reset control(s) of the amba bus and de-assert them.
409 */
410 rstc = of_reset_control_array_get_optional_shared(dev->dev.of_node);
411 if (IS_ERR(rstc)) {
412 ret = PTR_ERR(rstc);
413 if (ret != -EPROBE_DEFER)
414 dev_err(&dev->dev, "can't get reset: %d\n",
415 ret);
416 goto err_reset;
417 }
418 reset_control_deassert(rstc);
419 reset_control_put(rstc);
420
421 /*
422 * Read pid and cid based on size of resource
423 * they are located at end of region
424 */
425 for (pid = 0, i = 0; i < 4; i++)
426 pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) <<
427 (i * 8);
428 for (cid = 0, i = 0; i < 4; i++)
429 cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) <<
430 (i * 8);
431
432 if (cid == CORESIGHT_CID) {
433 /* set the base to the start of the last 4k block */
434 void __iomem *csbase = tmp + size - 4096;
435
436 dev->uci.devarch =
437 readl(csbase + UCI_REG_DEVARCH_OFFSET);
438 dev->uci.devtype =
439 readl(csbase + UCI_REG_DEVTYPE_OFFSET) & 0xff;
440 }
441
442 amba_put_disable_pclk(dev);
443
444 if (cid == AMBA_CID || cid == CORESIGHT_CID) {
445 dev->periphid = pid;
446 dev->cid = cid;
447 }
448
449 if (!dev->periphid)
450 ret = -ENODEV;
451 }
452
453 iounmap(tmp);
454 dev_pm_domain_detach(&dev->dev, true);
455
456 if (ret)
457 goto err_release;
458
459 skip_probe:
460 ret = device_add(&dev->dev);
461 if (ret)
462 goto err_release;
463
464 if (dev->irq[0])
465 ret = device_create_file(&dev->dev, &dev_attr_irq0);
466 if (ret == 0 && dev->irq[1])
467 ret = device_create_file(&dev->dev, &dev_attr_irq1);
468 if (ret == 0)
469 return ret;
470
471 device_unregister(&dev->dev);
472
473 err_release:
474 release_resource(&dev->res);
475 err_out:
476 return ret;
477
478 err_reset:
479 amba_put_disable_pclk(dev);
480 iounmap(tmp);
481 dev_pm_domain_detach(&dev->dev, true);
482 goto err_release;
483}
484
485/*
486 * Registration of AMBA device require reading its pid and cid registers.
487 * To do this, the device must be turned on (if it is a part of power domain)
488 * and have clocks enabled. However in some cases those resources might not be
489 * yet available. Returning EPROBE_DEFER is not a solution in such case,
490 * because callers don't handle this special error code. Instead such devices
491 * are added to the special list and their registration is retried from
492 * periodic worker, until all resources are available and registration succeeds.
493 */
494struct deferred_device {
495 struct amba_device *dev;
496 struct resource *parent;
497 struct list_head node;
498};
499
500static LIST_HEAD(deferred_devices);
501static DEFINE_MUTEX(deferred_devices_lock);
502
503static void amba_deferred_retry_func(struct work_struct *dummy);
504static DECLARE_DELAYED_WORK(deferred_retry_work, amba_deferred_retry_func);
505
506#define DEFERRED_DEVICE_TIMEOUT (msecs_to_jiffies(5 * 1000))
507
508static void amba_deferred_retry_func(struct work_struct *dummy)
509{
510 struct deferred_device *ddev, *tmp;
511
512 mutex_lock(&deferred_devices_lock);
513
514 list_for_each_entry_safe(ddev, tmp, &deferred_devices, node) {
515 int ret = amba_device_try_add(ddev->dev, ddev->parent);
516
517 if (ret == -EPROBE_DEFER)
518 continue;
519
520 list_del_init(&ddev->node);
521 kfree(ddev);
522 }
523
524 if (!list_empty(&deferred_devices))
525 schedule_delayed_work(&deferred_retry_work,
526 DEFERRED_DEVICE_TIMEOUT);
527
528 mutex_unlock(&deferred_devices_lock);
529}
530
531/**
532 * amba_device_add - add a previously allocated AMBA device structure
533 * @dev: AMBA device allocated by amba_device_alloc
534 * @parent: resource parent for this devices resources
535 *
536 * Claim the resource, and read the device cell ID if not already
537 * initialized. Register the AMBA device with the Linux device
538 * manager.
539 */
540int amba_device_add(struct amba_device *dev, struct resource *parent)
541{
542 int ret = amba_device_try_add(dev, parent);
543
544 if (ret == -EPROBE_DEFER) {
545 struct deferred_device *ddev;
546
547 ddev = kmalloc(sizeof(*ddev), GFP_KERNEL);
548 if (!ddev)
549 return -ENOMEM;
550
551 ddev->dev = dev;
552 ddev->parent = parent;
553 ret = 0;
554
555 mutex_lock(&deferred_devices_lock);
556
557 if (list_empty(&deferred_devices))
558 schedule_delayed_work(&deferred_retry_work,
559 DEFERRED_DEVICE_TIMEOUT);
560 list_add_tail(&ddev->node, &deferred_devices);
561
562 mutex_unlock(&deferred_devices_lock);
563 }
564 return ret;
565}
566EXPORT_SYMBOL_GPL(amba_device_add);
567
568static struct amba_device *
569amba_aphb_device_add(struct device *parent, const char *name,
570 resource_size_t base, size_t size, int irq1, int irq2,
571 void *pdata, unsigned int periphid, u64 dma_mask,
572 struct resource *resbase)
573{
574 struct amba_device *dev;
575 int ret;
576
577 dev = amba_device_alloc(name, base, size);
578 if (!dev)
579 return ERR_PTR(-ENOMEM);
580
581 dev->dev.coherent_dma_mask = dma_mask;
582 dev->irq[0] = irq1;
583 dev->irq[1] = irq2;
584 dev->periphid = periphid;
585 dev->dev.platform_data = pdata;
586 dev->dev.parent = parent;
587
588 ret = amba_device_add(dev, resbase);
589 if (ret) {
590 amba_device_put(dev);
591 return ERR_PTR(ret);
592 }
593
594 return dev;
595}
596
597struct amba_device *
598amba_apb_device_add(struct device *parent, const char *name,
599 resource_size_t base, size_t size, int irq1, int irq2,
600 void *pdata, unsigned int periphid)
601{
602 return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata,
603 periphid, 0, &iomem_resource);
604}
605EXPORT_SYMBOL_GPL(amba_apb_device_add);
606
607struct amba_device *
608amba_ahb_device_add(struct device *parent, const char *name,
609 resource_size_t base, size_t size, int irq1, int irq2,
610 void *pdata, unsigned int periphid)
611{
612 return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata,
613 periphid, ~0ULL, &iomem_resource);
614}
615EXPORT_SYMBOL_GPL(amba_ahb_device_add);
616
617struct amba_device *
618amba_apb_device_add_res(struct device *parent, const char *name,
619 resource_size_t base, size_t size, int irq1,
620 int irq2, void *pdata, unsigned int periphid,
621 struct resource *resbase)
622{
623 return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata,
624 periphid, 0, resbase);
625}
626EXPORT_SYMBOL_GPL(amba_apb_device_add_res);
627
628struct amba_device *
629amba_ahb_device_add_res(struct device *parent, const char *name,
630 resource_size_t base, size_t size, int irq1,
631 int irq2, void *pdata, unsigned int periphid,
632 struct resource *resbase)
633{
634 return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata,
635 periphid, ~0ULL, resbase);
636}
637EXPORT_SYMBOL_GPL(amba_ahb_device_add_res);
638
639
640static void amba_device_initialize(struct amba_device *dev, const char *name)
641{
642 device_initialize(&dev->dev);
643 if (name)
644 dev_set_name(&dev->dev, "%s", name);
645 dev->dev.release = amba_device_release;
646 dev->dev.bus = &amba_bustype;
647 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
648 dev->res.name = dev_name(&dev->dev);
649}
650
651/**
652 * amba_device_alloc - allocate an AMBA device
653 * @name: sysfs name of the AMBA device
654 * @base: base of AMBA device
655 * @size: size of AMBA device
656 *
657 * Allocate and initialize an AMBA device structure. Returns %NULL
658 * on failure.
659 */
660struct amba_device *amba_device_alloc(const char *name, resource_size_t base,
661 size_t size)
662{
663 struct amba_device *dev;
664
665 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
666 if (dev) {
667 amba_device_initialize(dev, name);
668 dev->res.start = base;
669 dev->res.end = base + size - 1;
670 dev->res.flags = IORESOURCE_MEM;
671 }
672
673 return dev;
674}
675EXPORT_SYMBOL_GPL(amba_device_alloc);
676
677/**
678 * amba_device_register - register an AMBA device
679 * @dev: AMBA device to register
680 * @parent: parent memory resource
681 *
682 * Setup the AMBA device, reading the cell ID if present.
683 * Claim the resource, and register the AMBA device with
684 * the Linux device manager.
685 */
686int amba_device_register(struct amba_device *dev, struct resource *parent)
687{
688 amba_device_initialize(dev, dev->dev.init_name);
689 dev->dev.init_name = NULL;
690
691 return amba_device_add(dev, parent);
692}
693
694/**
695 * amba_device_put - put an AMBA device
696 * @dev: AMBA device to put
697 */
698void amba_device_put(struct amba_device *dev)
699{
700 put_device(&dev->dev);
701}
702EXPORT_SYMBOL_GPL(amba_device_put);
703
704/**
705 * amba_device_unregister - unregister an AMBA device
706 * @dev: AMBA device to remove
707 *
708 * Remove the specified AMBA device from the Linux device
709 * manager. All files associated with this object will be
710 * destroyed, and device drivers notified that the device has
711 * been removed. The AMBA device's resources including
712 * the amba_device structure will be freed once all
713 * references to it have been dropped.
714 */
715void amba_device_unregister(struct amba_device *dev)
716{
717 device_unregister(&dev->dev);
718}
719
720
721struct find_data {
722 struct amba_device *dev;
723 struct device *parent;
724 const char *busid;
725 unsigned int id;
726 unsigned int mask;
727};
728
729static int amba_find_match(struct device *dev, void *data)
730{
731 struct find_data *d = data;
732 struct amba_device *pcdev = to_amba_device(dev);
733 int r;
734
735 r = (pcdev->periphid & d->mask) == d->id;
736 if (d->parent)
737 r &= d->parent == dev->parent;
738 if (d->busid)
739 r &= strcmp(dev_name(dev), d->busid) == 0;
740
741 if (r) {
742 get_device(dev);
743 d->dev = pcdev;
744 }
745
746 return r;
747}
748
749/**
750 * amba_find_device - locate an AMBA device given a bus id
751 * @busid: bus id for device (or NULL)
752 * @parent: parent device (or NULL)
753 * @id: peripheral ID (or 0)
754 * @mask: peripheral ID mask (or 0)
755 *
756 * Return the AMBA device corresponding to the supplied parameters.
757 * If no device matches, returns NULL.
758 *
759 * NOTE: When a valid device is found, its refcount is
760 * incremented, and must be decremented before the returned
761 * reference.
762 */
763struct amba_device *
764amba_find_device(const char *busid, struct device *parent, unsigned int id,
765 unsigned int mask)
766{
767 struct find_data data;
768
769 data.dev = NULL;
770 data.parent = parent;
771 data.busid = busid;
772 data.id = id;
773 data.mask = mask;
774
775 bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
776
777 return data.dev;
778}
779
780/**
781 * amba_request_regions - request all mem regions associated with device
782 * @dev: amba_device structure for device
783 * @name: name, or NULL to use driver name
784 */
785int amba_request_regions(struct amba_device *dev, const char *name)
786{
787 int ret = 0;
788 u32 size;
789
790 if (!name)
791 name = dev->dev.driver->name;
792
793 size = resource_size(&dev->res);
794
795 if (!request_mem_region(dev->res.start, size, name))
796 ret = -EBUSY;
797
798 return ret;
799}
800
801/**
802 * amba_release_regions - release mem regions associated with device
803 * @dev: amba_device structure for device
804 *
805 * Release regions claimed by a successful call to amba_request_regions.
806 */
807void amba_release_regions(struct amba_device *dev)
808{
809 u32 size;
810
811 size = resource_size(&dev->res);
812 release_mem_region(dev->res.start, size);
813}
814
815EXPORT_SYMBOL(amba_driver_register);
816EXPORT_SYMBOL(amba_driver_unregister);
817EXPORT_SYMBOL(amba_device_register);
818EXPORT_SYMBOL(amba_device_unregister);
819EXPORT_SYMBOL(amba_find_device);
820EXPORT_SYMBOL(amba_request_regions);
821EXPORT_SYMBOL(amba_release_regions);