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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/property.h>
22#include <linux/reset.h>
23#include <linux/of_irq.h>
24#include <linux/of_device.h>
25#include <linux/acpi.h>
26#include <linux/iommu.h>
27#include <linux/dma-map-ops.h>
28
29#define to_amba_driver(d) container_of(d, struct amba_driver, drv)
30
31/* called on periphid match and class 0x9 coresight device. */
32static int
33amba_cs_uci_id_match(const struct amba_id *table, struct amba_device *dev)
34{
35 int ret = 0;
36 struct amba_cs_uci_id *uci;
37
38 uci = table->data;
39
40 /* no table data or zero mask - return match on periphid */
41 if (!uci || (uci->devarch_mask == 0))
42 return 1;
43
44 /* test against read devtype and masked devarch value */
45 ret = (dev->uci.devtype == uci->devtype) &&
46 ((dev->uci.devarch & uci->devarch_mask) == uci->devarch);
47 return ret;
48}
49
50static const struct amba_id *
51amba_lookup(const struct amba_id *table, struct amba_device *dev)
52{
53 while (table->mask) {
54 if (((dev->periphid & table->mask) == table->id) &&
55 ((dev->cid != CORESIGHT_CID) ||
56 (amba_cs_uci_id_match(table, dev))))
57 return table;
58 table++;
59 }
60 return NULL;
61}
62
63static int amba_get_enable_pclk(struct amba_device *pcdev)
64{
65 int ret;
66
67 pcdev->pclk = clk_get(&pcdev->dev, "apb_pclk");
68 if (IS_ERR(pcdev->pclk))
69 return PTR_ERR(pcdev->pclk);
70
71 ret = clk_prepare_enable(pcdev->pclk);
72 if (ret)
73 clk_put(pcdev->pclk);
74
75 return ret;
76}
77
78static void amba_put_disable_pclk(struct amba_device *pcdev)
79{
80 clk_disable_unprepare(pcdev->pclk);
81 clk_put(pcdev->pclk);
82}
83
84
85static ssize_t driver_override_show(struct device *_dev,
86 struct device_attribute *attr, char *buf)
87{
88 struct amba_device *dev = to_amba_device(_dev);
89 ssize_t len;
90
91 device_lock(_dev);
92 len = sprintf(buf, "%s\n", dev->driver_override);
93 device_unlock(_dev);
94 return len;
95}
96
97static ssize_t driver_override_store(struct device *_dev,
98 struct device_attribute *attr,
99 const char *buf, size_t count)
100{
101 struct amba_device *dev = to_amba_device(_dev);
102 int ret;
103
104 ret = driver_set_override(_dev, &dev->driver_override, buf, count);
105 if (ret)
106 return ret;
107
108 return count;
109}
110static DEVICE_ATTR_RW(driver_override);
111
112#define amba_attr_func(name,fmt,arg...) \
113static ssize_t name##_show(struct device *_dev, \
114 struct device_attribute *attr, char *buf) \
115{ \
116 struct amba_device *dev = to_amba_device(_dev); \
117 return sprintf(buf, fmt, arg); \
118} \
119static DEVICE_ATTR_RO(name)
120
121amba_attr_func(id, "%08x\n", dev->periphid);
122amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n",
123 (unsigned long long)dev->res.start, (unsigned long long)dev->res.end,
124 dev->res.flags);
125
126static struct attribute *amba_dev_attrs[] = {
127 &dev_attr_id.attr,
128 &dev_attr_resource.attr,
129 &dev_attr_driver_override.attr,
130 NULL,
131};
132ATTRIBUTE_GROUPS(amba_dev);
133
134static int amba_read_periphid(struct amba_device *dev)
135{
136 struct reset_control *rstc;
137 u32 size, pid, cid;
138 void __iomem *tmp;
139 int i, ret;
140
141 ret = dev_pm_domain_attach(&dev->dev, true);
142 if (ret) {
143 dev_dbg(&dev->dev, "can't get PM domain: %d\n", ret);
144 goto err_out;
145 }
146
147 ret = amba_get_enable_pclk(dev);
148 if (ret) {
149 dev_dbg(&dev->dev, "can't get pclk: %d\n", ret);
150 goto err_pm;
151 }
152
153 /*
154 * Find reset control(s) of the amba bus and de-assert them.
155 */
156 rstc = of_reset_control_array_get_optional_shared(dev->dev.of_node);
157 if (IS_ERR(rstc)) {
158 ret = PTR_ERR(rstc);
159 if (ret != -EPROBE_DEFER)
160 dev_err(&dev->dev, "can't get reset: %d\n", ret);
161 goto err_clk;
162 }
163 reset_control_deassert(rstc);
164 reset_control_put(rstc);
165
166 size = resource_size(&dev->res);
167 tmp = ioremap(dev->res.start, size);
168 if (!tmp) {
169 ret = -ENOMEM;
170 goto err_clk;
171 }
172
173 /*
174 * Read pid and cid based on size of resource
175 * they are located at end of region
176 */
177 for (pid = 0, i = 0; i < 4; i++)
178 pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) << (i * 8);
179 for (cid = 0, i = 0; i < 4; i++)
180 cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) << (i * 8);
181
182 if (cid == CORESIGHT_CID) {
183 /* set the base to the start of the last 4k block */
184 void __iomem *csbase = tmp + size - 4096;
185
186 dev->uci.devarch = readl(csbase + UCI_REG_DEVARCH_OFFSET);
187 dev->uci.devtype = readl(csbase + UCI_REG_DEVTYPE_OFFSET) & 0xff;
188 }
189
190 if (cid == AMBA_CID || cid == CORESIGHT_CID) {
191 dev->periphid = pid;
192 dev->cid = cid;
193 }
194
195 if (!dev->periphid)
196 ret = -ENODEV;
197
198 iounmap(tmp);
199
200err_clk:
201 amba_put_disable_pclk(dev);
202err_pm:
203 dev_pm_domain_detach(&dev->dev, true);
204err_out:
205 return ret;
206}
207
208static int amba_match(struct device *dev, struct device_driver *drv)
209{
210 struct amba_device *pcdev = to_amba_device(dev);
211 struct amba_driver *pcdrv = to_amba_driver(drv);
212
213 mutex_lock(&pcdev->periphid_lock);
214 if (!pcdev->periphid) {
215 int ret = amba_read_periphid(pcdev);
216
217 /*
218 * Returning any error other than -EPROBE_DEFER from bus match
219 * can cause driver registration failure. So, if there's a
220 * permanent failure in reading pid and cid, simply map it to
221 * -EPROBE_DEFER.
222 */
223 if (ret) {
224 mutex_unlock(&pcdev->periphid_lock);
225 return -EPROBE_DEFER;
226 }
227 dev_set_uevent_suppress(dev, false);
228 kobject_uevent(&dev->kobj, KOBJ_ADD);
229 }
230 mutex_unlock(&pcdev->periphid_lock);
231
232 /* When driver_override is set, only bind to the matching driver */
233 if (pcdev->driver_override)
234 return !strcmp(pcdev->driver_override, drv->name);
235
236 return amba_lookup(pcdrv->id_table, pcdev) != NULL;
237}
238
239static int amba_uevent(const struct device *dev, struct kobj_uevent_env *env)
240{
241 const struct amba_device *pcdev = to_amba_device(dev);
242 int retval = 0;
243
244 retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid);
245 if (retval)
246 return retval;
247
248 retval = add_uevent_var(env, "MODALIAS=amba:d%08X", pcdev->periphid);
249 return retval;
250}
251
252static int of_amba_device_decode_irq(struct amba_device *dev)
253{
254 struct device_node *node = dev->dev.of_node;
255 int i, irq = 0;
256
257 if (IS_ENABLED(CONFIG_OF_IRQ) && node) {
258 /* Decode the IRQs and address ranges */
259 for (i = 0; i < AMBA_NR_IRQS; i++) {
260 irq = of_irq_get(node, i);
261 if (irq < 0) {
262 if (irq == -EPROBE_DEFER)
263 return irq;
264 irq = 0;
265 }
266
267 dev->irq[i] = irq;
268 }
269 }
270
271 return 0;
272}
273
274/*
275 * These are the device model conversion veneers; they convert the
276 * device model structures to our more specific structures.
277 */
278static int amba_probe(struct device *dev)
279{
280 struct amba_device *pcdev = to_amba_device(dev);
281 struct amba_driver *pcdrv = to_amba_driver(dev->driver);
282 const struct amba_id *id = amba_lookup(pcdrv->id_table, pcdev);
283 int ret;
284
285 do {
286 ret = of_amba_device_decode_irq(pcdev);
287 if (ret)
288 break;
289
290 ret = of_clk_set_defaults(dev->of_node, false);
291 if (ret < 0)
292 break;
293
294 ret = dev_pm_domain_attach(dev, true);
295 if (ret)
296 break;
297
298 ret = amba_get_enable_pclk(pcdev);
299 if (ret) {
300 dev_pm_domain_detach(dev, true);
301 break;
302 }
303
304 pm_runtime_get_noresume(dev);
305 pm_runtime_set_active(dev);
306 pm_runtime_enable(dev);
307
308 ret = pcdrv->probe(pcdev, id);
309 if (ret == 0)
310 break;
311
312 pm_runtime_disable(dev);
313 pm_runtime_set_suspended(dev);
314 pm_runtime_put_noidle(dev);
315
316 amba_put_disable_pclk(pcdev);
317 dev_pm_domain_detach(dev, true);
318 } while (0);
319
320 return ret;
321}
322
323static void amba_remove(struct device *dev)
324{
325 struct amba_device *pcdev = to_amba_device(dev);
326 struct amba_driver *drv = to_amba_driver(dev->driver);
327
328 pm_runtime_get_sync(dev);
329 if (drv->remove)
330 drv->remove(pcdev);
331 pm_runtime_put_noidle(dev);
332
333 /* Undo the runtime PM settings in amba_probe() */
334 pm_runtime_disable(dev);
335 pm_runtime_set_suspended(dev);
336 pm_runtime_put_noidle(dev);
337
338 amba_put_disable_pclk(pcdev);
339 dev_pm_domain_detach(dev, true);
340}
341
342static void amba_shutdown(struct device *dev)
343{
344 struct amba_driver *drv;
345
346 if (!dev->driver)
347 return;
348
349 drv = to_amba_driver(dev->driver);
350 if (drv->shutdown)
351 drv->shutdown(to_amba_device(dev));
352}
353
354static int amba_dma_configure(struct device *dev)
355{
356 struct amba_driver *drv = to_amba_driver(dev->driver);
357 enum dev_dma_attr attr;
358 int ret = 0;
359
360 if (dev->of_node) {
361 ret = of_dma_configure(dev, dev->of_node, true);
362 } else if (has_acpi_companion(dev)) {
363 attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
364 ret = acpi_dma_configure(dev, attr);
365 }
366
367 if (!ret && !drv->driver_managed_dma) {
368 ret = iommu_device_use_default_domain(dev);
369 if (ret)
370 arch_teardown_dma_ops(dev);
371 }
372
373 return ret;
374}
375
376static void amba_dma_cleanup(struct device *dev)
377{
378 struct amba_driver *drv = to_amba_driver(dev->driver);
379
380 if (!drv->driver_managed_dma)
381 iommu_device_unuse_default_domain(dev);
382}
383
384#ifdef CONFIG_PM
385/*
386 * Hooks to provide runtime PM of the pclk (bus clock). It is safe to
387 * enable/disable the bus clock at runtime PM suspend/resume as this
388 * does not result in loss of context.
389 */
390static int amba_pm_runtime_suspend(struct device *dev)
391{
392 struct amba_device *pcdev = to_amba_device(dev);
393 int ret = pm_generic_runtime_suspend(dev);
394
395 if (ret == 0 && dev->driver) {
396 if (pm_runtime_is_irq_safe(dev))
397 clk_disable(pcdev->pclk);
398 else
399 clk_disable_unprepare(pcdev->pclk);
400 }
401
402 return ret;
403}
404
405static int amba_pm_runtime_resume(struct device *dev)
406{
407 struct amba_device *pcdev = to_amba_device(dev);
408 int ret;
409
410 if (dev->driver) {
411 if (pm_runtime_is_irq_safe(dev))
412 ret = clk_enable(pcdev->pclk);
413 else
414 ret = clk_prepare_enable(pcdev->pclk);
415 /* Failure is probably fatal to the system, but... */
416 if (ret)
417 return ret;
418 }
419
420 return pm_generic_runtime_resume(dev);
421}
422#endif /* CONFIG_PM */
423
424static const struct dev_pm_ops amba_pm = {
425 SET_RUNTIME_PM_OPS(
426 amba_pm_runtime_suspend,
427 amba_pm_runtime_resume,
428 NULL
429 )
430};
431
432/*
433 * Primecells are part of the Advanced Microcontroller Bus Architecture,
434 * so we call the bus "amba".
435 * DMA configuration for platform and AMBA bus is same. So here we reuse
436 * platform's DMA config routine.
437 */
438struct bus_type amba_bustype = {
439 .name = "amba",
440 .dev_groups = amba_dev_groups,
441 .match = amba_match,
442 .uevent = amba_uevent,
443 .probe = amba_probe,
444 .remove = amba_remove,
445 .shutdown = amba_shutdown,
446 .dma_configure = amba_dma_configure,
447 .dma_cleanup = amba_dma_cleanup,
448 .pm = &amba_pm,
449};
450EXPORT_SYMBOL_GPL(amba_bustype);
451
452static int __init amba_init(void)
453{
454 return bus_register(&amba_bustype);
455}
456
457postcore_initcall(amba_init);
458
459static int amba_proxy_probe(struct amba_device *adev,
460 const struct amba_id *id)
461{
462 WARN(1, "Stub driver should never match any device.\n");
463 return -ENODEV;
464}
465
466static const struct amba_id amba_stub_drv_ids[] = {
467 { 0, 0 },
468};
469
470static struct amba_driver amba_proxy_drv = {
471 .drv = {
472 .name = "amba-proxy",
473 },
474 .probe = amba_proxy_probe,
475 .id_table = amba_stub_drv_ids,
476};
477
478static int __init amba_stub_drv_init(void)
479{
480 if (!IS_ENABLED(CONFIG_MODULES))
481 return 0;
482
483 /*
484 * The amba_match() function will get called only if there is at least
485 * one amba driver registered. If all amba drivers are modules and are
486 * only loaded based on uevents, then we'll hit a chicken-and-egg
487 * situation where amba_match() is waiting on drivers and drivers are
488 * waiting on amba_match(). So, register a stub driver to make sure
489 * amba_match() is called even if no amba driver has been registered.
490 */
491 return amba_driver_register(&amba_proxy_drv);
492}
493late_initcall_sync(amba_stub_drv_init);
494
495/**
496 * amba_driver_register - register an AMBA device driver
497 * @drv: amba device driver structure
498 *
499 * Register an AMBA device driver with the Linux device model
500 * core. If devices pre-exist, the drivers probe function will
501 * be called.
502 */
503int amba_driver_register(struct amba_driver *drv)
504{
505 if (!drv->probe)
506 return -EINVAL;
507
508 drv->drv.bus = &amba_bustype;
509
510 return driver_register(&drv->drv);
511}
512EXPORT_SYMBOL(amba_driver_register);
513
514/**
515 * amba_driver_unregister - remove an AMBA device driver
516 * @drv: AMBA device driver structure to remove
517 *
518 * Unregister an AMBA device driver from the Linux device
519 * model. The device model will call the drivers remove function
520 * for each device the device driver is currently handling.
521 */
522void amba_driver_unregister(struct amba_driver *drv)
523{
524 driver_unregister(&drv->drv);
525}
526EXPORT_SYMBOL(amba_driver_unregister);
527
528static void amba_device_release(struct device *dev)
529{
530 struct amba_device *d = to_amba_device(dev);
531
532 fwnode_handle_put(dev_fwnode(&d->dev));
533 if (d->res.parent)
534 release_resource(&d->res);
535 mutex_destroy(&d->periphid_lock);
536 kfree(d);
537}
538
539/**
540 * amba_device_add - add a previously allocated AMBA device structure
541 * @dev: AMBA device allocated by amba_device_alloc
542 * @parent: resource parent for this devices resources
543 *
544 * Claim the resource, and read the device cell ID if not already
545 * initialized. Register the AMBA device with the Linux device
546 * manager.
547 */
548int amba_device_add(struct amba_device *dev, struct resource *parent)
549{
550 int ret;
551
552 fwnode_handle_get(dev_fwnode(&dev->dev));
553
554 ret = request_resource(parent, &dev->res);
555 if (ret)
556 return ret;
557
558 /* If primecell ID isn't hard-coded, figure it out */
559 if (!dev->periphid) {
560 /*
561 * AMBA device uevents require reading its pid and cid
562 * registers. To do this, the device must be on, clocked and
563 * out of reset. However in some cases those resources might
564 * not yet be available. If that's the case, we suppress the
565 * generation of uevents until we can read the pid and cid
566 * registers. See also amba_match().
567 */
568 if (amba_read_periphid(dev))
569 dev_set_uevent_suppress(&dev->dev, true);
570 }
571
572 ret = device_add(&dev->dev);
573 if (ret)
574 release_resource(&dev->res);
575
576 return ret;
577}
578EXPORT_SYMBOL_GPL(amba_device_add);
579
580static void amba_device_initialize(struct amba_device *dev, const char *name)
581{
582 device_initialize(&dev->dev);
583 if (name)
584 dev_set_name(&dev->dev, "%s", name);
585 dev->dev.release = amba_device_release;
586 dev->dev.bus = &amba_bustype;
587 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
588 dev->dev.dma_parms = &dev->dma_parms;
589 dev->res.name = dev_name(&dev->dev);
590 mutex_init(&dev->periphid_lock);
591}
592
593/**
594 * amba_device_alloc - allocate an AMBA device
595 * @name: sysfs name of the AMBA device
596 * @base: base of AMBA device
597 * @size: size of AMBA device
598 *
599 * Allocate and initialize an AMBA device structure. Returns %NULL
600 * on failure.
601 */
602struct amba_device *amba_device_alloc(const char *name, resource_size_t base,
603 size_t size)
604{
605 struct amba_device *dev;
606
607 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
608 if (dev) {
609 amba_device_initialize(dev, name);
610 dev->res.start = base;
611 dev->res.end = base + size - 1;
612 dev->res.flags = IORESOURCE_MEM;
613 }
614
615 return dev;
616}
617EXPORT_SYMBOL_GPL(amba_device_alloc);
618
619/**
620 * amba_device_register - register an AMBA device
621 * @dev: AMBA device to register
622 * @parent: parent memory resource
623 *
624 * Setup the AMBA device, reading the cell ID if present.
625 * Claim the resource, and register the AMBA device with
626 * the Linux device manager.
627 */
628int amba_device_register(struct amba_device *dev, struct resource *parent)
629{
630 amba_device_initialize(dev, dev->dev.init_name);
631 dev->dev.init_name = NULL;
632
633 return amba_device_add(dev, parent);
634}
635EXPORT_SYMBOL(amba_device_register);
636
637/**
638 * amba_device_put - put an AMBA device
639 * @dev: AMBA device to put
640 */
641void amba_device_put(struct amba_device *dev)
642{
643 put_device(&dev->dev);
644}
645EXPORT_SYMBOL_GPL(amba_device_put);
646
647/**
648 * amba_device_unregister - unregister an AMBA device
649 * @dev: AMBA device to remove
650 *
651 * Remove the specified AMBA device from the Linux device
652 * manager. All files associated with this object will be
653 * destroyed, and device drivers notified that the device has
654 * been removed. The AMBA device's resources including
655 * the amba_device structure will be freed once all
656 * references to it have been dropped.
657 */
658void amba_device_unregister(struct amba_device *dev)
659{
660 device_unregister(&dev->dev);
661}
662EXPORT_SYMBOL(amba_device_unregister);
663
664/**
665 * amba_request_regions - request all mem regions associated with device
666 * @dev: amba_device structure for device
667 * @name: name, or NULL to use driver name
668 */
669int amba_request_regions(struct amba_device *dev, const char *name)
670{
671 int ret = 0;
672 u32 size;
673
674 if (!name)
675 name = dev->dev.driver->name;
676
677 size = resource_size(&dev->res);
678
679 if (!request_mem_region(dev->res.start, size, name))
680 ret = -EBUSY;
681
682 return ret;
683}
684EXPORT_SYMBOL(amba_request_regions);
685
686/**
687 * amba_release_regions - release mem regions associated with device
688 * @dev: amba_device structure for device
689 *
690 * Release regions claimed by a successful call to amba_request_regions.
691 */
692void amba_release_regions(struct amba_device *dev)
693{
694 u32 size;
695
696 size = resource_size(&dev->res);
697 release_mem_region(dev->res.start, size);
698}
699EXPORT_SYMBOL(amba_release_regions);