1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * CDX bus driver.
4 *
5 * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
6 */
7
8 /*
9 * Architecture Overview
10 * =====================
11 * CDX is a Hardware Architecture designed for AMD FPGA devices. It
12 * consists of sophisticated mechanism for interaction between FPGA,
13 * Firmware and the APUs (Application CPUs).
14 *
15 * Firmware resides on RPU (Realtime CPUs) which interacts with
16 * the FPGA program manager and the APUs. The RPU provides memory-mapped
17 * interface (RPU if) which is used to communicate with APUs.
18 *
19 * The diagram below shows an overview of the CDX architecture:
20 *
21 * +--------------------------------------+
22 * | Application CPUs (APU) |
23 * | |
24 * | CDX device drivers|
25 * | Linux OS | |
26 * | CDX bus |
27 * | | |
28 * | CDX controller |
29 * | | |
30 * +-----------------------------|--------+
31 * | (discover, config,
32 * | reset, rescan)
33 * |
34 * +------------------------| RPU if |----+
35 * | | |
36 * | V |
37 * | Realtime CPUs (RPU) |
38 * | |
39 * +--------------------------------------+
40 * |
41 * +---------------------|----------------+
42 * | FPGA | |
43 * | +-----------------------+ |
44 * | | | | |
45 * | +-------+ +-------+ +-------+ |
46 * | | dev 1 | | dev 2 | | dev 3 | |
47 * | +-------+ +-------+ +-------+ |
48 * +--------------------------------------+
49 *
50 * The RPU firmware extracts the device information from the loaded FPGA
51 * image and implements a mechanism that allows the APU drivers to
52 * enumerate such devices (device personality and resource details) via
53 * a dedicated communication channel. RPU mediates operations such as
54 * discover, reset and rescan of the FPGA devices for the APU. This is
55 * done using memory mapped interface provided by the RPU to APU.
56 */
57
58 #include <linux/init.h>
59 #include <linux/irqdomain.h>
60 #include <linux/kernel.h>
61 #include <linux/of.h>
62 #include <linux/of_device.h>
63 #include <linux/of_platform.h>
64 #include <linux/platform_device.h>
65 #include <linux/slab.h>
66 #include <linux/mm.h>
67 #include <linux/idr.h>
68 #include <linux/cdx/cdx_bus.h>
69 #include <linux/iommu.h>
70 #include <linux/dma-map-ops.h>
71 #include <linux/debugfs.h>
72 #include "cdx.h"
73
74 /* Default DMA mask for devices on a CDX bus */
75 #define CDX_DEFAULT_DMA_MASK (~0ULL)
76 #define MAX_CDX_CONTROLLERS 16
77
78 /* IDA for CDX controllers registered with the CDX bus */
79 static DEFINE_IDA(cdx_controller_ida);
80 /* Lock to protect controller ops */
81 static DEFINE_MUTEX(cdx_controller_lock);
82 /* Debugfs dir for cdx bus */
83 static struct dentry *cdx_debugfs_dir;
84
85 static char *compat_node_name = "xlnx,versal-net-cdx";
86
87 static void cdx_destroy_res_attr(struct cdx_device *cdx_dev, int num);
88
89 /**
90 * cdx_dev_reset - Reset a CDX device
91 * @dev: CDX device
92 *
93 * Return: -errno on failure, 0 on success.
94 */
cdx_dev_reset(struct device * dev)95 int cdx_dev_reset(struct device *dev)
96 {
97 struct cdx_device *cdx_dev = to_cdx_device(dev);
98 struct cdx_controller *cdx = cdx_dev->cdx;
99 struct cdx_device_config dev_config = {0};
100 struct cdx_driver *cdx_drv;
101 int ret;
102
103 cdx_drv = to_cdx_driver(dev->driver);
104 /* Notify driver that device is being reset */
105 if (cdx_drv && cdx_drv->reset_prepare)
106 cdx_drv->reset_prepare(cdx_dev);
107
108 dev_config.type = CDX_DEV_RESET_CONF;
109 ret = cdx->ops->dev_configure(cdx, cdx_dev->bus_num,
110 cdx_dev->dev_num, &dev_config);
111 if (ret)
112 dev_err(dev, "cdx device reset failed\n");
113
114 /* Notify driver that device reset is complete */
115 if (cdx_drv && cdx_drv->reset_done)
116 cdx_drv->reset_done(cdx_dev);
117
118 return ret;
119 }
120 EXPORT_SYMBOL_GPL(cdx_dev_reset);
121
122 /**
123 * reset_cdx_device - Reset a CDX device
124 * @dev: CDX device
125 * @data: This is always passed as NULL, and is not used in this API,
126 * but is required here as the device_for_each_child() API expects
127 * the passed function to have this as an argument.
128 *
129 * Return: -errno on failure, 0 on success.
130 */
reset_cdx_device(struct device * dev,void * data)131 static int reset_cdx_device(struct device *dev, void *data)
132 {
133 return cdx_dev_reset(dev);
134 }
135
136 /**
137 * cdx_unregister_device - Unregister a CDX device
138 * @dev: CDX device
139 * @data: This is always passed as NULL, and is not used in this API,
140 * but is required here as the bus_for_each_dev() API expects
141 * the passed function (cdx_unregister_device) to have this
142 * as an argument.
143 *
144 * Return: 0 on success.
145 */
cdx_unregister_device(struct device * dev,void * data)146 static int cdx_unregister_device(struct device *dev,
147 void *data)
148 {
149 struct cdx_device *cdx_dev = to_cdx_device(dev);
150 struct cdx_controller *cdx = cdx_dev->cdx;
151
152 if (cdx_dev->is_bus) {
153 device_for_each_child(dev, NULL, cdx_unregister_device);
154 if (cdx_dev->enabled && cdx->ops->bus_disable)
155 cdx->ops->bus_disable(cdx, cdx_dev->bus_num);
156 } else {
157 cdx_destroy_res_attr(cdx_dev, MAX_CDX_DEV_RESOURCES);
158 debugfs_remove_recursive(cdx_dev->debugfs_dir);
159 kfree(cdx_dev->driver_override);
160 cdx_dev->driver_override = NULL;
161 }
162
163 /*
164 * Do not free cdx_dev here as it would be freed in
165 * cdx_device_release() called from within put_device().
166 */
167 device_del(&cdx_dev->dev);
168 put_device(&cdx_dev->dev);
169
170 return 0;
171 }
172
cdx_unregister_devices(struct bus_type * bus)173 static void cdx_unregister_devices(struct bus_type *bus)
174 {
175 /* Reset all the devices attached to cdx bus */
176 bus_for_each_dev(bus, NULL, NULL, cdx_unregister_device);
177 }
178
179 /**
180 * cdx_match_one_device - Tell if a CDX device structure has a matching
181 * CDX device id structure
182 * @id: single CDX device id structure to match
183 * @dev: the CDX device structure to match against
184 *
185 * Return: matching cdx_device_id structure or NULL if there is no match.
186 */
187 static inline const struct cdx_device_id *
cdx_match_one_device(const struct cdx_device_id * id,const struct cdx_device * dev)188 cdx_match_one_device(const struct cdx_device_id *id,
189 const struct cdx_device *dev)
190 {
191 /* Use vendor ID and device ID for matching */
192 if ((id->vendor == CDX_ANY_ID || id->vendor == dev->vendor) &&
193 (id->device == CDX_ANY_ID || id->device == dev->device) &&
194 (id->subvendor == CDX_ANY_ID || id->subvendor == dev->subsystem_vendor) &&
195 (id->subdevice == CDX_ANY_ID || id->subdevice == dev->subsystem_device) &&
196 !((id->class ^ dev->class) & id->class_mask))
197 return id;
198 return NULL;
199 }
200
201 /**
202 * cdx_match_id - See if a CDX device matches a given cdx_id table
203 * @ids: array of CDX device ID structures to search in
204 * @dev: the CDX device structure to match against.
205 *
206 * Used by a driver to check whether a CDX device is in its list of
207 * supported devices. Returns the matching cdx_device_id structure or
208 * NULL if there is no match.
209 *
210 * Return: matching cdx_device_id structure or NULL if there is no match.
211 */
212 static inline const struct cdx_device_id *
cdx_match_id(const struct cdx_device_id * ids,struct cdx_device * dev)213 cdx_match_id(const struct cdx_device_id *ids, struct cdx_device *dev)
214 {
215 if (ids) {
216 while (ids->vendor || ids->device) {
217 if (cdx_match_one_device(ids, dev))
218 return ids;
219 ids++;
220 }
221 }
222 return NULL;
223 }
224
cdx_set_master(struct cdx_device * cdx_dev)225 int cdx_set_master(struct cdx_device *cdx_dev)
226 {
227 struct cdx_controller *cdx = cdx_dev->cdx;
228 struct cdx_device_config dev_config;
229 int ret = -EOPNOTSUPP;
230
231 dev_config.type = CDX_DEV_BUS_MASTER_CONF;
232 dev_config.bus_master_enable = true;
233 if (cdx->ops->dev_configure)
234 ret = cdx->ops->dev_configure(cdx, cdx_dev->bus_num,
235 cdx_dev->dev_num, &dev_config);
236
237 return ret;
238 }
239 EXPORT_SYMBOL_GPL(cdx_set_master);
240
cdx_clear_master(struct cdx_device * cdx_dev)241 int cdx_clear_master(struct cdx_device *cdx_dev)
242 {
243 struct cdx_controller *cdx = cdx_dev->cdx;
244 struct cdx_device_config dev_config;
245 int ret = -EOPNOTSUPP;
246
247 dev_config.type = CDX_DEV_BUS_MASTER_CONF;
248 dev_config.bus_master_enable = false;
249 if (cdx->ops->dev_configure)
250 ret = cdx->ops->dev_configure(cdx, cdx_dev->bus_num,
251 cdx_dev->dev_num, &dev_config);
252
253 return ret;
254 }
255 EXPORT_SYMBOL_GPL(cdx_clear_master);
256
257 /**
258 * cdx_bus_match - device to driver matching callback
259 * @dev: the cdx device to match against
260 * @drv: the device driver to search for matching cdx device
261 * structures
262 *
263 * Return: true on success, false otherwise.
264 */
cdx_bus_match(struct device * dev,const struct device_driver * drv)265 static int cdx_bus_match(struct device *dev, const struct device_driver *drv)
266 {
267 struct cdx_device *cdx_dev = to_cdx_device(dev);
268 const struct cdx_driver *cdx_drv = to_cdx_driver(drv);
269 const struct cdx_device_id *found_id = NULL;
270 const struct cdx_device_id *ids;
271
272 if (cdx_dev->is_bus)
273 return false;
274
275 ids = cdx_drv->match_id_table;
276
277 /* When driver_override is set, only bind to the matching driver */
278 if (cdx_dev->driver_override && strcmp(cdx_dev->driver_override, drv->name))
279 return false;
280
281 found_id = cdx_match_id(ids, cdx_dev);
282 if (!found_id)
283 return false;
284
285 do {
286 /*
287 * In case override_only was set, enforce driver_override
288 * matching.
289 */
290 if (!found_id->override_only)
291 return true;
292 if (cdx_dev->driver_override)
293 return true;
294
295 ids = found_id + 1;
296 found_id = cdx_match_id(ids, cdx_dev);
297 } while (found_id);
298
299 return false;
300 }
301
cdx_probe(struct device * dev)302 static int cdx_probe(struct device *dev)
303 {
304 struct cdx_driver *cdx_drv = to_cdx_driver(dev->driver);
305 struct cdx_device *cdx_dev = to_cdx_device(dev);
306 struct cdx_controller *cdx = cdx_dev->cdx;
307 int error;
308
309 /*
310 * Setup MSI device data so that generic MSI alloc/free can
311 * be used by the device driver.
312 */
313 if (cdx->msi_domain) {
314 error = msi_setup_device_data(&cdx_dev->dev);
315 if (error)
316 return error;
317 }
318
319 error = cdx_drv->probe(cdx_dev);
320 if (error) {
321 dev_err_probe(dev, error, "%s failed\n", __func__);
322 return error;
323 }
324
325 return 0;
326 }
327
cdx_remove(struct device * dev)328 static void cdx_remove(struct device *dev)
329 {
330 struct cdx_driver *cdx_drv = to_cdx_driver(dev->driver);
331 struct cdx_device *cdx_dev = to_cdx_device(dev);
332
333 if (cdx_drv && cdx_drv->remove)
334 cdx_drv->remove(cdx_dev);
335 }
336
cdx_shutdown(struct device * dev)337 static void cdx_shutdown(struct device *dev)
338 {
339 struct cdx_driver *cdx_drv = to_cdx_driver(dev->driver);
340 struct cdx_device *cdx_dev = to_cdx_device(dev);
341
342 if (cdx_drv && cdx_drv->shutdown)
343 cdx_drv->shutdown(cdx_dev);
344 }
345
cdx_dma_configure(struct device * dev)346 static int cdx_dma_configure(struct device *dev)
347 {
348 struct cdx_driver *cdx_drv = to_cdx_driver(dev->driver);
349 struct cdx_device *cdx_dev = to_cdx_device(dev);
350 struct cdx_controller *cdx = cdx_dev->cdx;
351 u32 input_id = cdx_dev->req_id;
352 int ret;
353
354 ret = of_dma_configure_id(dev, cdx->dev->of_node, 0, &input_id);
355 if (ret && ret != -EPROBE_DEFER) {
356 dev_err(dev, "of_dma_configure_id() failed\n");
357 return ret;
358 }
359
360 if (!ret && !cdx_drv->driver_managed_dma) {
361 ret = iommu_device_use_default_domain(dev);
362 if (ret)
363 arch_teardown_dma_ops(dev);
364 }
365
366 return 0;
367 }
368
cdx_dma_cleanup(struct device * dev)369 static void cdx_dma_cleanup(struct device *dev)
370 {
371 struct cdx_driver *cdx_drv = to_cdx_driver(dev->driver);
372
373 if (!cdx_drv->driver_managed_dma)
374 iommu_device_unuse_default_domain(dev);
375 }
376
377 /* show configuration fields */
378 #define cdx_config_attr(field, format_string) \
379 static ssize_t \
380 field##_show(struct device *dev, struct device_attribute *attr, char *buf) \
381 { \
382 struct cdx_device *cdx_dev = to_cdx_device(dev); \
383 return sysfs_emit(buf, format_string, cdx_dev->field); \
384 } \
385 static DEVICE_ATTR_RO(field)
386
387 cdx_config_attr(vendor, "0x%04x\n");
388 cdx_config_attr(device, "0x%04x\n");
389 cdx_config_attr(subsystem_vendor, "0x%04x\n");
390 cdx_config_attr(subsystem_device, "0x%04x\n");
391 cdx_config_attr(revision, "0x%02x\n");
392 cdx_config_attr(class, "0x%06x\n");
393
remove_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)394 static ssize_t remove_store(struct device *dev,
395 struct device_attribute *attr,
396 const char *buf, size_t count)
397 {
398 bool val;
399
400 if (kstrtobool(buf, &val) < 0)
401 return -EINVAL;
402
403 if (!val)
404 return -EINVAL;
405
406 if (device_remove_file_self(dev, attr)) {
407 int ret;
408
409 ret = cdx_unregister_device(dev, NULL);
410 if (ret)
411 return ret;
412 }
413
414 return count;
415 }
416 static DEVICE_ATTR_WO(remove);
417
reset_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)418 static ssize_t reset_store(struct device *dev, struct device_attribute *attr,
419 const char *buf, size_t count)
420 {
421 struct cdx_device *cdx_dev = to_cdx_device(dev);
422 bool val;
423 int ret;
424
425 if (kstrtobool(buf, &val) < 0)
426 return -EINVAL;
427
428 if (!val)
429 return -EINVAL;
430
431 if (cdx_dev->is_bus)
432 /* Reset all the devices attached to cdx bus */
433 ret = device_for_each_child(dev, NULL, reset_cdx_device);
434 else
435 ret = cdx_dev_reset(dev);
436
437 return ret < 0 ? ret : count;
438 }
439 static DEVICE_ATTR_WO(reset);
440
modalias_show(struct device * dev,struct device_attribute * attr,char * buf)441 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
442 char *buf)
443 {
444 struct cdx_device *cdx_dev = to_cdx_device(dev);
445
446 return sprintf(buf, "cdx:v%04Xd%04Xsv%04Xsd%04Xc%06X\n", cdx_dev->vendor,
447 cdx_dev->device, cdx_dev->subsystem_vendor, cdx_dev->subsystem_device,
448 cdx_dev->class);
449 }
450 static DEVICE_ATTR_RO(modalias);
451
driver_override_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)452 static ssize_t driver_override_store(struct device *dev,
453 struct device_attribute *attr,
454 const char *buf, size_t count)
455 {
456 struct cdx_device *cdx_dev = to_cdx_device(dev);
457 int ret;
458
459 if (WARN_ON(dev->bus != &cdx_bus_type))
460 return -EINVAL;
461
462 ret = driver_set_override(dev, &cdx_dev->driver_override, buf, count);
463 if (ret)
464 return ret;
465
466 return count;
467 }
468
driver_override_show(struct device * dev,struct device_attribute * attr,char * buf)469 static ssize_t driver_override_show(struct device *dev,
470 struct device_attribute *attr, char *buf)
471 {
472 struct cdx_device *cdx_dev = to_cdx_device(dev);
473 ssize_t len;
474
475 device_lock(dev);
476 len = sysfs_emit(buf, "%s\n", cdx_dev->driver_override);
477 device_unlock(dev);
478 return len;
479 }
480 static DEVICE_ATTR_RW(driver_override);
481
enable_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)482 static ssize_t enable_store(struct device *dev, struct device_attribute *attr,
483 const char *buf, size_t count)
484 {
485 struct cdx_device *cdx_dev = to_cdx_device(dev);
486 struct cdx_controller *cdx = cdx_dev->cdx;
487 bool enable;
488 int ret;
489
490 if (kstrtobool(buf, &enable) < 0)
491 return -EINVAL;
492
493 if (enable == cdx_dev->enabled)
494 return count;
495
496 if (enable && cdx->ops->bus_enable)
497 ret = cdx->ops->bus_enable(cdx, cdx_dev->bus_num);
498 else if (!enable && cdx->ops->bus_disable)
499 ret = cdx->ops->bus_disable(cdx, cdx_dev->bus_num);
500 else
501 ret = -EOPNOTSUPP;
502
503 if (!ret)
504 cdx_dev->enabled = enable;
505
506 return ret < 0 ? ret : count;
507 }
508
enable_show(struct device * dev,struct device_attribute * attr,char * buf)509 static ssize_t enable_show(struct device *dev, struct device_attribute *attr, char *buf)
510 {
511 struct cdx_device *cdx_dev = to_cdx_device(dev);
512
513 return sysfs_emit(buf, "%u\n", cdx_dev->enabled);
514 }
515 static DEVICE_ATTR_RW(enable);
516
cdx_dev_attrs_are_visible(struct kobject * kobj,struct attribute * a,int n)517 static umode_t cdx_dev_attrs_are_visible(struct kobject *kobj, struct attribute *a, int n)
518 {
519 struct device *dev = kobj_to_dev(kobj);
520 struct cdx_device *cdx_dev;
521
522 cdx_dev = to_cdx_device(dev);
523 if (!cdx_dev->is_bus)
524 return a->mode;
525
526 return 0;
527 }
528
cdx_bus_attrs_are_visible(struct kobject * kobj,struct attribute * a,int n)529 static umode_t cdx_bus_attrs_are_visible(struct kobject *kobj, struct attribute *a, int n)
530 {
531 struct device *dev = kobj_to_dev(kobj);
532 struct cdx_device *cdx_dev;
533
534 cdx_dev = to_cdx_device(dev);
535 if (cdx_dev->is_bus)
536 return a->mode;
537
538 return 0;
539 }
540
541 static struct attribute *cdx_dev_attrs[] = {
542 &dev_attr_remove.attr,
543 &dev_attr_reset.attr,
544 &dev_attr_vendor.attr,
545 &dev_attr_device.attr,
546 &dev_attr_subsystem_vendor.attr,
547 &dev_attr_subsystem_device.attr,
548 &dev_attr_class.attr,
549 &dev_attr_revision.attr,
550 &dev_attr_modalias.attr,
551 &dev_attr_driver_override.attr,
552 NULL,
553 };
554
555 static const struct attribute_group cdx_dev_group = {
556 .attrs = cdx_dev_attrs,
557 .is_visible = cdx_dev_attrs_are_visible,
558 };
559
560 static struct attribute *cdx_bus_dev_attrs[] = {
561 &dev_attr_enable.attr,
562 &dev_attr_reset.attr,
563 NULL,
564 };
565
566 static const struct attribute_group cdx_bus_dev_group = {
567 .attrs = cdx_bus_dev_attrs,
568 .is_visible = cdx_bus_attrs_are_visible,
569 };
570
571 static const struct attribute_group *cdx_dev_groups[] = {
572 &cdx_dev_group,
573 &cdx_bus_dev_group,
574 NULL,
575 };
576
cdx_debug_resource_show(struct seq_file * s,void * data)577 static int cdx_debug_resource_show(struct seq_file *s, void *data)
578 {
579 struct cdx_device *cdx_dev = s->private;
580 int i;
581
582 for (i = 0; i < MAX_CDX_DEV_RESOURCES; i++) {
583 struct resource *res = &cdx_dev->res[i];
584
585 seq_printf(s, "%pr\n", res);
586 }
587
588 return 0;
589 }
590 DEFINE_SHOW_ATTRIBUTE(cdx_debug_resource);
591
cdx_device_debugfs_init(struct cdx_device * cdx_dev)592 static void cdx_device_debugfs_init(struct cdx_device *cdx_dev)
593 {
594 cdx_dev->debugfs_dir = debugfs_create_dir(dev_name(&cdx_dev->dev), cdx_debugfs_dir);
595 if (IS_ERR(cdx_dev->debugfs_dir))
596 return;
597
598 debugfs_create_file("resource", 0444, cdx_dev->debugfs_dir, cdx_dev,
599 &cdx_debug_resource_fops);
600 }
601
rescan_store(const struct bus_type * bus,const char * buf,size_t count)602 static ssize_t rescan_store(const struct bus_type *bus,
603 const char *buf, size_t count)
604 {
605 struct cdx_controller *cdx;
606 struct platform_device *pd;
607 struct device_node *np;
608 bool val;
609
610 if (kstrtobool(buf, &val) < 0)
611 return -EINVAL;
612
613 if (!val)
614 return -EINVAL;
615
616 mutex_lock(&cdx_controller_lock);
617
618 /* Unregister all the devices on the bus */
619 cdx_unregister_devices(&cdx_bus_type);
620
621 /* Rescan all the devices */
622 for_each_compatible_node(np, NULL, compat_node_name) {
623 pd = of_find_device_by_node(np);
624 if (!pd) {
625 of_node_put(np);
626 count = -EINVAL;
627 goto unlock;
628 }
629
630 cdx = platform_get_drvdata(pd);
631 if (cdx && cdx->controller_registered && cdx->ops->scan)
632 cdx->ops->scan(cdx);
633
634 put_device(&pd->dev);
635 }
636
637 unlock:
638 mutex_unlock(&cdx_controller_lock);
639
640 return count;
641 }
642 static BUS_ATTR_WO(rescan);
643
644 static struct attribute *cdx_bus_attrs[] = {
645 &bus_attr_rescan.attr,
646 NULL,
647 };
648 ATTRIBUTE_GROUPS(cdx_bus);
649
650 struct bus_type cdx_bus_type = {
651 .name = "cdx",
652 .match = cdx_bus_match,
653 .probe = cdx_probe,
654 .remove = cdx_remove,
655 .shutdown = cdx_shutdown,
656 .dma_configure = cdx_dma_configure,
657 .dma_cleanup = cdx_dma_cleanup,
658 .bus_groups = cdx_bus_groups,
659 .dev_groups = cdx_dev_groups,
660 };
661 EXPORT_SYMBOL_GPL(cdx_bus_type);
662
__cdx_driver_register(struct cdx_driver * cdx_driver,struct module * owner)663 int __cdx_driver_register(struct cdx_driver *cdx_driver,
664 struct module *owner)
665 {
666 int error;
667
668 cdx_driver->driver.owner = owner;
669 cdx_driver->driver.bus = &cdx_bus_type;
670
671 error = driver_register(&cdx_driver->driver);
672 if (error) {
673 pr_err("driver_register() failed for %s: %d\n",
674 cdx_driver->driver.name, error);
675 return error;
676 }
677
678 return 0;
679 }
680 EXPORT_SYMBOL_GPL(__cdx_driver_register);
681
cdx_driver_unregister(struct cdx_driver * cdx_driver)682 void cdx_driver_unregister(struct cdx_driver *cdx_driver)
683 {
684 driver_unregister(&cdx_driver->driver);
685 }
686 EXPORT_SYMBOL_GPL(cdx_driver_unregister);
687
cdx_device_release(struct device * dev)688 static void cdx_device_release(struct device *dev)
689 {
690 struct cdx_device *cdx_dev = to_cdx_device(dev);
691
692 kfree(cdx_dev);
693 }
694
695 static const struct vm_operations_struct cdx_phys_vm_ops = {
696 #ifdef CONFIG_HAVE_IOREMAP_PROT
697 .access = generic_access_phys,
698 #endif
699 };
700
701 /**
702 * cdx_mmap_resource - map a CDX resource into user memory space
703 * @fp: File pointer. Not used in this function, but required where
704 * this API is registered as a callback.
705 * @kobj: kobject for mapping
706 * @attr: struct bin_attribute for the file being mapped
707 * @vma: struct vm_area_struct passed into the mmap
708 *
709 * Use the regular CDX mapping routines to map a CDX resource into userspace.
710 *
711 * Return: true on success, false otherwise.
712 */
cdx_mmap_resource(struct file * fp,struct kobject * kobj,struct bin_attribute * attr,struct vm_area_struct * vma)713 static int cdx_mmap_resource(struct file *fp, struct kobject *kobj,
714 struct bin_attribute *attr,
715 struct vm_area_struct *vma)
716 {
717 struct cdx_device *cdx_dev = to_cdx_device(kobj_to_dev(kobj));
718 int num = (unsigned long)attr->private;
719 struct resource *res;
720 unsigned long size;
721
722 res = &cdx_dev->res[num];
723 if (iomem_is_exclusive(res->start))
724 return -EINVAL;
725
726 /* Make sure the caller is mapping a valid resource for this device */
727 size = ((cdx_resource_len(cdx_dev, num) - 1) >> PAGE_SHIFT) + 1;
728 if (vma->vm_pgoff + vma_pages(vma) > size)
729 return -EINVAL;
730
731 /*
732 * Map memory region and vm->vm_pgoff is expected to be an
733 * offset within that region.
734 */
735 vma->vm_page_prot = pgprot_device(vma->vm_page_prot);
736 vma->vm_pgoff += (cdx_resource_start(cdx_dev, num) >> PAGE_SHIFT);
737 vma->vm_ops = &cdx_phys_vm_ops;
738 return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
739 vma->vm_end - vma->vm_start,
740 vma->vm_page_prot);
741 }
742
cdx_destroy_res_attr(struct cdx_device * cdx_dev,int num)743 static void cdx_destroy_res_attr(struct cdx_device *cdx_dev, int num)
744 {
745 int i;
746
747 /* removing the bin attributes */
748 for (i = 0; i < num; i++) {
749 struct bin_attribute *res_attr;
750
751 res_attr = cdx_dev->res_attr[i];
752 if (res_attr) {
753 sysfs_remove_bin_file(&cdx_dev->dev.kobj, res_attr);
754 kfree(res_attr);
755 }
756 }
757 }
758
759 #define CDX_RES_ATTR_NAME_LEN 10
cdx_create_res_attr(struct cdx_device * cdx_dev,int num)760 static int cdx_create_res_attr(struct cdx_device *cdx_dev, int num)
761 {
762 struct bin_attribute *res_attr;
763 char *res_attr_name;
764 int ret;
765
766 res_attr = kzalloc(sizeof(*res_attr) + CDX_RES_ATTR_NAME_LEN, GFP_ATOMIC);
767 if (!res_attr)
768 return -ENOMEM;
769
770 res_attr_name = (char *)(res_attr + 1);
771
772 sysfs_bin_attr_init(res_attr);
773
774 cdx_dev->res_attr[num] = res_attr;
775 sprintf(res_attr_name, "resource%d", num);
776
777 res_attr->mmap = cdx_mmap_resource;
778 res_attr->attr.name = res_attr_name;
779 res_attr->attr.mode = 0600;
780 res_attr->size = cdx_resource_len(cdx_dev, num);
781 res_attr->private = (void *)(unsigned long)num;
782 ret = sysfs_create_bin_file(&cdx_dev->dev.kobj, res_attr);
783 if (ret)
784 kfree(res_attr);
785
786 return ret;
787 }
788
cdx_device_add(struct cdx_dev_params * dev_params)789 int cdx_device_add(struct cdx_dev_params *dev_params)
790 {
791 struct cdx_controller *cdx = dev_params->cdx;
792 struct cdx_device *cdx_dev;
793 int ret, i;
794
795 cdx_dev = kzalloc(sizeof(*cdx_dev), GFP_KERNEL);
796 if (!cdx_dev)
797 return -ENOMEM;
798
799 /* Populate resource */
800 memcpy(cdx_dev->res, dev_params->res, sizeof(struct resource) *
801 dev_params->res_count);
802 cdx_dev->res_count = dev_params->res_count;
803
804 /* Populate CDX dev params */
805 cdx_dev->req_id = dev_params->req_id;
806 cdx_dev->msi_dev_id = dev_params->msi_dev_id;
807 cdx_dev->vendor = dev_params->vendor;
808 cdx_dev->device = dev_params->device;
809 cdx_dev->subsystem_vendor = dev_params->subsys_vendor;
810 cdx_dev->subsystem_device = dev_params->subsys_device;
811 cdx_dev->class = dev_params->class;
812 cdx_dev->revision = dev_params->revision;
813 cdx_dev->bus_num = dev_params->bus_num;
814 cdx_dev->dev_num = dev_params->dev_num;
815 cdx_dev->cdx = dev_params->cdx;
816 cdx_dev->dma_mask = CDX_DEFAULT_DMA_MASK;
817
818 /* Initialize generic device */
819 device_initialize(&cdx_dev->dev);
820 cdx_dev->dev.parent = dev_params->parent;
821 cdx_dev->dev.bus = &cdx_bus_type;
822 cdx_dev->dev.dma_mask = &cdx_dev->dma_mask;
823 cdx_dev->dev.release = cdx_device_release;
824 cdx_dev->msi_write_pending = false;
825 mutex_init(&cdx_dev->irqchip_lock);
826
827 /* Set Name */
828 dev_set_name(&cdx_dev->dev, "cdx-%02x:%02x",
829 ((cdx->id << CDX_CONTROLLER_ID_SHIFT) | (cdx_dev->bus_num & CDX_BUS_NUM_MASK)),
830 cdx_dev->dev_num);
831
832 if (cdx->msi_domain) {
833 cdx_dev->num_msi = dev_params->num_msi;
834 dev_set_msi_domain(&cdx_dev->dev, cdx->msi_domain);
835 }
836
837 ret = device_add(&cdx_dev->dev);
838 if (ret) {
839 dev_err(&cdx_dev->dev,
840 "cdx device add failed: %d", ret);
841 goto fail;
842 }
843
844 /* Create resource<N> attributes */
845 for (i = 0; i < MAX_CDX_DEV_RESOURCES; i++) {
846 if (cdx_resource_flags(cdx_dev, i) & IORESOURCE_MEM) {
847 /* skip empty resources */
848 if (!cdx_resource_len(cdx_dev, i))
849 continue;
850
851 ret = cdx_create_res_attr(cdx_dev, i);
852 if (ret != 0) {
853 dev_err(&cdx_dev->dev,
854 "cdx device resource<%d> file creation failed: %d", i, ret);
855 goto resource_create_fail;
856 }
857 }
858 }
859
860 cdx_device_debugfs_init(cdx_dev);
861
862 return 0;
863 resource_create_fail:
864 cdx_destroy_res_attr(cdx_dev, i);
865 device_del(&cdx_dev->dev);
866 fail:
867 /*
868 * Do not free cdx_dev here as it would be freed in
869 * cdx_device_release() called from put_device().
870 */
871 put_device(&cdx_dev->dev);
872
873 return ret;
874 }
875 EXPORT_SYMBOL_NS_GPL(cdx_device_add, CDX_BUS_CONTROLLER);
876
cdx_bus_add(struct cdx_controller * cdx,u8 bus_num)877 struct device *cdx_bus_add(struct cdx_controller *cdx, u8 bus_num)
878 {
879 struct cdx_device *cdx_dev;
880 int ret;
881
882 cdx_dev = kzalloc(sizeof(*cdx_dev), GFP_KERNEL);
883 if (!cdx_dev)
884 return NULL;
885
886 device_initialize(&cdx_dev->dev);
887 cdx_dev->cdx = cdx;
888
889 cdx_dev->dev.parent = cdx->dev;
890 cdx_dev->dev.bus = &cdx_bus_type;
891 cdx_dev->dev.release = cdx_device_release;
892 cdx_dev->is_bus = true;
893 cdx_dev->bus_num = bus_num;
894
895 dev_set_name(&cdx_dev->dev, "cdx-%02x",
896 ((cdx->id << CDX_CONTROLLER_ID_SHIFT) | (bus_num & CDX_BUS_NUM_MASK)));
897
898 ret = device_add(&cdx_dev->dev);
899 if (ret) {
900 dev_err(&cdx_dev->dev, "cdx bus device add failed: %d\n", ret);
901 goto device_add_fail;
902 }
903
904 if (cdx->ops->bus_enable) {
905 ret = cdx->ops->bus_enable(cdx, bus_num);
906 if (ret && ret != -EALREADY) {
907 dev_err(cdx->dev, "cdx bus enable failed: %d\n", ret);
908 goto bus_enable_fail;
909 }
910 }
911
912 cdx_dev->enabled = true;
913 return &cdx_dev->dev;
914
915 bus_enable_fail:
916 device_del(&cdx_dev->dev);
917 device_add_fail:
918 put_device(&cdx_dev->dev);
919
920 return NULL;
921 }
922 EXPORT_SYMBOL_NS_GPL(cdx_bus_add, CDX_BUS_CONTROLLER);
923
cdx_register_controller(struct cdx_controller * cdx)924 int cdx_register_controller(struct cdx_controller *cdx)
925 {
926 int ret;
927
928 ret = ida_alloc_range(&cdx_controller_ida, 0, MAX_CDX_CONTROLLERS - 1, GFP_KERNEL);
929 if (ret < 0) {
930 dev_err(cdx->dev,
931 "No free index available. Maximum controllers already registered\n");
932 cdx->id = (u8)MAX_CDX_CONTROLLERS;
933 return ret;
934 }
935
936 mutex_lock(&cdx_controller_lock);
937 cdx->id = ret;
938
939 /* Scan all the devices */
940 if (cdx->ops->scan)
941 cdx->ops->scan(cdx);
942 cdx->controller_registered = true;
943 mutex_unlock(&cdx_controller_lock);
944
945 return 0;
946 }
947 EXPORT_SYMBOL_NS_GPL(cdx_register_controller, CDX_BUS_CONTROLLER);
948
cdx_unregister_controller(struct cdx_controller * cdx)949 void cdx_unregister_controller(struct cdx_controller *cdx)
950 {
951 if (cdx->id >= MAX_CDX_CONTROLLERS)
952 return;
953
954 mutex_lock(&cdx_controller_lock);
955
956 cdx->controller_registered = false;
957 device_for_each_child(cdx->dev, NULL, cdx_unregister_device);
958 ida_free(&cdx_controller_ida, cdx->id);
959
960 mutex_unlock(&cdx_controller_lock);
961 }
962 EXPORT_SYMBOL_NS_GPL(cdx_unregister_controller, CDX_BUS_CONTROLLER);
963
cdx_bus_init(void)964 static int __init cdx_bus_init(void)
965 {
966 int ret;
967
968 ret = bus_register(&cdx_bus_type);
969 if (!ret)
970 cdx_debugfs_dir = debugfs_create_dir(cdx_bus_type.name, NULL);
971
972 return ret;
973 }
974 postcore_initcall(cdx_bus_init);
975