Merge tag 'media/v6.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...
[platform/kernel/linux-starfive.git] / drivers / fpga / dfl.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for FPGA Device Feature List (DFL) Support
4  *
5  * Copyright (C) 2017-2018 Intel Corporation, Inc.
6  *
7  * Authors:
8  *   Kang Luwei <luwei.kang@intel.com>
9  *   Zhang Yi <yi.z.zhang@intel.com>
10  *   Wu Hao <hao.wu@intel.com>
11  *   Xiao Guangrong <guangrong.xiao@linux.intel.com>
12  */
13 #include <linux/dfl.h>
14 #include <linux/fpga-dfl.h>
15 #include <linux/module.h>
16 #include <linux/uaccess.h>
17
18 #include "dfl.h"
19
20 static DEFINE_MUTEX(dfl_id_mutex);
21
22 /*
23  * when adding a new feature dev support in DFL framework, it's required to
24  * add a new item in enum dfl_id_type and provide related information in below
25  * dfl_devs table which is indexed by dfl_id_type, e.g. name string used for
26  * platform device creation (define name strings in dfl.h, as they could be
27  * reused by platform device drivers).
28  *
29  * if the new feature dev needs chardev support, then it's required to add
30  * a new item in dfl_chardevs table and configure dfl_devs[i].devt_type as
31  * index to dfl_chardevs table. If no chardev support just set devt_type
32  * as one invalid index (DFL_FPGA_DEVT_MAX).
33  */
34 enum dfl_fpga_devt_type {
35         DFL_FPGA_DEVT_FME,
36         DFL_FPGA_DEVT_PORT,
37         DFL_FPGA_DEVT_MAX,
38 };
39
40 static struct lock_class_key dfl_pdata_keys[DFL_ID_MAX];
41
42 static const char *dfl_pdata_key_strings[DFL_ID_MAX] = {
43         "dfl-fme-pdata",
44         "dfl-port-pdata",
45 };
46
47 /**
48  * dfl_dev_info - dfl feature device information.
49  * @name: name string of the feature platform device.
50  * @dfh_id: id value in Device Feature Header (DFH) register by DFL spec.
51  * @id: idr id of the feature dev.
52  * @devt_type: index to dfl_chrdevs[].
53  */
54 struct dfl_dev_info {
55         const char *name;
56         u16 dfh_id;
57         struct idr id;
58         enum dfl_fpga_devt_type devt_type;
59 };
60
61 /* it is indexed by dfl_id_type */
62 static struct dfl_dev_info dfl_devs[] = {
63         {.name = DFL_FPGA_FEATURE_DEV_FME, .dfh_id = DFH_ID_FIU_FME,
64          .devt_type = DFL_FPGA_DEVT_FME},
65         {.name = DFL_FPGA_FEATURE_DEV_PORT, .dfh_id = DFH_ID_FIU_PORT,
66          .devt_type = DFL_FPGA_DEVT_PORT},
67 };
68
69 /**
70  * dfl_chardev_info - chardev information of dfl feature device
71  * @name: nmae string of the char device.
72  * @devt: devt of the char device.
73  */
74 struct dfl_chardev_info {
75         const char *name;
76         dev_t devt;
77 };
78
79 /* indexed by enum dfl_fpga_devt_type */
80 static struct dfl_chardev_info dfl_chrdevs[] = {
81         {.name = DFL_FPGA_FEATURE_DEV_FME},
82         {.name = DFL_FPGA_FEATURE_DEV_PORT},
83 };
84
85 static void dfl_ids_init(void)
86 {
87         int i;
88
89         for (i = 0; i < ARRAY_SIZE(dfl_devs); i++)
90                 idr_init(&dfl_devs[i].id);
91 }
92
93 static void dfl_ids_destroy(void)
94 {
95         int i;
96
97         for (i = 0; i < ARRAY_SIZE(dfl_devs); i++)
98                 idr_destroy(&dfl_devs[i].id);
99 }
100
101 static int dfl_id_alloc(enum dfl_id_type type, struct device *dev)
102 {
103         int id;
104
105         WARN_ON(type >= DFL_ID_MAX);
106         mutex_lock(&dfl_id_mutex);
107         id = idr_alloc(&dfl_devs[type].id, dev, 0, 0, GFP_KERNEL);
108         mutex_unlock(&dfl_id_mutex);
109
110         return id;
111 }
112
113 static void dfl_id_free(enum dfl_id_type type, int id)
114 {
115         WARN_ON(type >= DFL_ID_MAX);
116         mutex_lock(&dfl_id_mutex);
117         idr_remove(&dfl_devs[type].id, id);
118         mutex_unlock(&dfl_id_mutex);
119 }
120
121 static enum dfl_id_type feature_dev_id_type(struct platform_device *pdev)
122 {
123         int i;
124
125         for (i = 0; i < ARRAY_SIZE(dfl_devs); i++)
126                 if (!strcmp(dfl_devs[i].name, pdev->name))
127                         return i;
128
129         return DFL_ID_MAX;
130 }
131
132 static enum dfl_id_type dfh_id_to_type(u16 id)
133 {
134         int i;
135
136         for (i = 0; i < ARRAY_SIZE(dfl_devs); i++)
137                 if (dfl_devs[i].dfh_id == id)
138                         return i;
139
140         return DFL_ID_MAX;
141 }
142
143 /*
144  * introduce a global port_ops list, it allows port drivers to register ops
145  * in such list, then other feature devices (e.g. FME), could use the port
146  * functions even related port platform device is hidden. Below is one example,
147  * in virtualization case of PCIe-based FPGA DFL device, when SRIOV is
148  * enabled, port (and it's AFU) is turned into VF and port platform device
149  * is hidden from system but it's still required to access port to finish FPGA
150  * reconfiguration function in FME.
151  */
152
153 static DEFINE_MUTEX(dfl_port_ops_mutex);
154 static LIST_HEAD(dfl_port_ops_list);
155
156 /**
157  * dfl_fpga_port_ops_get - get matched port ops from the global list
158  * @pdev: platform device to match with associated port ops.
159  * Return: matched port ops on success, NULL otherwise.
160  *
161  * Please note that must dfl_fpga_port_ops_put after use the port_ops.
162  */
163 struct dfl_fpga_port_ops *dfl_fpga_port_ops_get(struct platform_device *pdev)
164 {
165         struct dfl_fpga_port_ops *ops = NULL;
166
167         mutex_lock(&dfl_port_ops_mutex);
168         if (list_empty(&dfl_port_ops_list))
169                 goto done;
170
171         list_for_each_entry(ops, &dfl_port_ops_list, node) {
172                 /* match port_ops using the name of platform device */
173                 if (!strcmp(pdev->name, ops->name)) {
174                         if (!try_module_get(ops->owner))
175                                 ops = NULL;
176                         goto done;
177                 }
178         }
179
180         ops = NULL;
181 done:
182         mutex_unlock(&dfl_port_ops_mutex);
183         return ops;
184 }
185 EXPORT_SYMBOL_GPL(dfl_fpga_port_ops_get);
186
187 /**
188  * dfl_fpga_port_ops_put - put port ops
189  * @ops: port ops.
190  */
191 void dfl_fpga_port_ops_put(struct dfl_fpga_port_ops *ops)
192 {
193         if (ops && ops->owner)
194                 module_put(ops->owner);
195 }
196 EXPORT_SYMBOL_GPL(dfl_fpga_port_ops_put);
197
198 /**
199  * dfl_fpga_port_ops_add - add port_ops to global list
200  * @ops: port ops to add.
201  */
202 void dfl_fpga_port_ops_add(struct dfl_fpga_port_ops *ops)
203 {
204         mutex_lock(&dfl_port_ops_mutex);
205         list_add_tail(&ops->node, &dfl_port_ops_list);
206         mutex_unlock(&dfl_port_ops_mutex);
207 }
208 EXPORT_SYMBOL_GPL(dfl_fpga_port_ops_add);
209
210 /**
211  * dfl_fpga_port_ops_del - remove port_ops from global list
212  * @ops: port ops to del.
213  */
214 void dfl_fpga_port_ops_del(struct dfl_fpga_port_ops *ops)
215 {
216         mutex_lock(&dfl_port_ops_mutex);
217         list_del(&ops->node);
218         mutex_unlock(&dfl_port_ops_mutex);
219 }
220 EXPORT_SYMBOL_GPL(dfl_fpga_port_ops_del);
221
222 /**
223  * dfl_fpga_check_port_id - check the port id
224  * @pdev: port platform device.
225  * @pport_id: port id to compare.
226  *
227  * Return: 1 if port device matches with given port id, otherwise 0.
228  */
229 int dfl_fpga_check_port_id(struct platform_device *pdev, void *pport_id)
230 {
231         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
232         struct dfl_fpga_port_ops *port_ops;
233
234         if (pdata->id != FEATURE_DEV_ID_UNUSED)
235                 return pdata->id == *(int *)pport_id;
236
237         port_ops = dfl_fpga_port_ops_get(pdev);
238         if (!port_ops || !port_ops->get_id)
239                 return 0;
240
241         pdata->id = port_ops->get_id(pdev);
242         dfl_fpga_port_ops_put(port_ops);
243
244         return pdata->id == *(int *)pport_id;
245 }
246 EXPORT_SYMBOL_GPL(dfl_fpga_check_port_id);
247
248 static DEFINE_IDA(dfl_device_ida);
249
250 static const struct dfl_device_id *
251 dfl_match_one_device(const struct dfl_device_id *id, struct dfl_device *ddev)
252 {
253         if (id->type == ddev->type && id->feature_id == ddev->feature_id)
254                 return id;
255
256         return NULL;
257 }
258
259 static int dfl_bus_match(struct device *dev, struct device_driver *drv)
260 {
261         struct dfl_device *ddev = to_dfl_dev(dev);
262         struct dfl_driver *ddrv = to_dfl_drv(drv);
263         const struct dfl_device_id *id_entry;
264
265         id_entry = ddrv->id_table;
266         if (id_entry) {
267                 while (id_entry->feature_id) {
268                         if (dfl_match_one_device(id_entry, ddev)) {
269                                 ddev->id_entry = id_entry;
270                                 return 1;
271                         }
272                         id_entry++;
273                 }
274         }
275
276         return 0;
277 }
278
279 static int dfl_bus_probe(struct device *dev)
280 {
281         struct dfl_driver *ddrv = to_dfl_drv(dev->driver);
282         struct dfl_device *ddev = to_dfl_dev(dev);
283
284         return ddrv->probe(ddev);
285 }
286
287 static void dfl_bus_remove(struct device *dev)
288 {
289         struct dfl_driver *ddrv = to_dfl_drv(dev->driver);
290         struct dfl_device *ddev = to_dfl_dev(dev);
291
292         if (ddrv->remove)
293                 ddrv->remove(ddev);
294 }
295
296 static int dfl_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
297 {
298         struct dfl_device *ddev = to_dfl_dev(dev);
299
300         return add_uevent_var(env, "MODALIAS=dfl:t%04Xf%04X",
301                               ddev->type, ddev->feature_id);
302 }
303
304 static ssize_t
305 type_show(struct device *dev, struct device_attribute *attr, char *buf)
306 {
307         struct dfl_device *ddev = to_dfl_dev(dev);
308
309         return sprintf(buf, "0x%x\n", ddev->type);
310 }
311 static DEVICE_ATTR_RO(type);
312
313 static ssize_t
314 feature_id_show(struct device *dev, struct device_attribute *attr, char *buf)
315 {
316         struct dfl_device *ddev = to_dfl_dev(dev);
317
318         return sprintf(buf, "0x%x\n", ddev->feature_id);
319 }
320 static DEVICE_ATTR_RO(feature_id);
321
322 static struct attribute *dfl_dev_attrs[] = {
323         &dev_attr_type.attr,
324         &dev_attr_feature_id.attr,
325         NULL,
326 };
327 ATTRIBUTE_GROUPS(dfl_dev);
328
329 static struct bus_type dfl_bus_type = {
330         .name           = "dfl",
331         .match          = dfl_bus_match,
332         .probe          = dfl_bus_probe,
333         .remove         = dfl_bus_remove,
334         .uevent         = dfl_bus_uevent,
335         .dev_groups     = dfl_dev_groups,
336 };
337
338 static void release_dfl_dev(struct device *dev)
339 {
340         struct dfl_device *ddev = to_dfl_dev(dev);
341
342         if (ddev->mmio_res.parent)
343                 release_resource(&ddev->mmio_res);
344
345         ida_free(&dfl_device_ida, ddev->id);
346         kfree(ddev->irqs);
347         kfree(ddev);
348 }
349
350 static struct dfl_device *
351 dfl_dev_add(struct dfl_feature_platform_data *pdata,
352             struct dfl_feature *feature)
353 {
354         struct platform_device *pdev = pdata->dev;
355         struct resource *parent_res;
356         struct dfl_device *ddev;
357         int id, i, ret;
358
359         ddev = kzalloc(sizeof(*ddev), GFP_KERNEL);
360         if (!ddev)
361                 return ERR_PTR(-ENOMEM);
362
363         id = ida_alloc(&dfl_device_ida, GFP_KERNEL);
364         if (id < 0) {
365                 dev_err(&pdev->dev, "unable to get id\n");
366                 kfree(ddev);
367                 return ERR_PTR(id);
368         }
369
370         /* freeing resources by put_device() after device_initialize() */
371         device_initialize(&ddev->dev);
372         ddev->dev.parent = &pdev->dev;
373         ddev->dev.bus = &dfl_bus_type;
374         ddev->dev.release = release_dfl_dev;
375         ddev->id = id;
376         ret = dev_set_name(&ddev->dev, "dfl_dev.%d", id);
377         if (ret)
378                 goto put_dev;
379
380         ddev->type = feature_dev_id_type(pdev);
381         ddev->feature_id = feature->id;
382         ddev->revision = feature->revision;
383         ddev->cdev = pdata->dfl_cdev;
384
385         /* add mmio resource */
386         parent_res = &pdev->resource[feature->resource_index];
387         ddev->mmio_res.flags = IORESOURCE_MEM;
388         ddev->mmio_res.start = parent_res->start;
389         ddev->mmio_res.end = parent_res->end;
390         ddev->mmio_res.name = dev_name(&ddev->dev);
391         ret = insert_resource(parent_res, &ddev->mmio_res);
392         if (ret) {
393                 dev_err(&pdev->dev, "%s failed to claim resource: %pR\n",
394                         dev_name(&ddev->dev), &ddev->mmio_res);
395                 goto put_dev;
396         }
397
398         /* then add irq resource */
399         if (feature->nr_irqs) {
400                 ddev->irqs = kcalloc(feature->nr_irqs,
401                                      sizeof(*ddev->irqs), GFP_KERNEL);
402                 if (!ddev->irqs) {
403                         ret = -ENOMEM;
404                         goto put_dev;
405                 }
406
407                 for (i = 0; i < feature->nr_irqs; i++)
408                         ddev->irqs[i] = feature->irq_ctx[i].irq;
409
410                 ddev->num_irqs = feature->nr_irqs;
411         }
412
413         ret = device_add(&ddev->dev);
414         if (ret)
415                 goto put_dev;
416
417         dev_dbg(&pdev->dev, "add dfl_dev: %s\n", dev_name(&ddev->dev));
418         return ddev;
419
420 put_dev:
421         /* calls release_dfl_dev() which does the clean up  */
422         put_device(&ddev->dev);
423         return ERR_PTR(ret);
424 }
425
426 static void dfl_devs_remove(struct dfl_feature_platform_data *pdata)
427 {
428         struct dfl_feature *feature;
429
430         dfl_fpga_dev_for_each_feature(pdata, feature) {
431                 if (feature->ddev) {
432                         device_unregister(&feature->ddev->dev);
433                         feature->ddev = NULL;
434                 }
435         }
436 }
437
438 static int dfl_devs_add(struct dfl_feature_platform_data *pdata)
439 {
440         struct dfl_feature *feature;
441         struct dfl_device *ddev;
442         int ret;
443
444         dfl_fpga_dev_for_each_feature(pdata, feature) {
445                 if (feature->ioaddr)
446                         continue;
447
448                 if (feature->ddev) {
449                         ret = -EEXIST;
450                         goto err;
451                 }
452
453                 ddev = dfl_dev_add(pdata, feature);
454                 if (IS_ERR(ddev)) {
455                         ret = PTR_ERR(ddev);
456                         goto err;
457                 }
458
459                 feature->ddev = ddev;
460         }
461
462         return 0;
463
464 err:
465         dfl_devs_remove(pdata);
466         return ret;
467 }
468
469 int __dfl_driver_register(struct dfl_driver *dfl_drv, struct module *owner)
470 {
471         if (!dfl_drv || !dfl_drv->probe || !dfl_drv->id_table)
472                 return -EINVAL;
473
474         dfl_drv->drv.owner = owner;
475         dfl_drv->drv.bus = &dfl_bus_type;
476
477         return driver_register(&dfl_drv->drv);
478 }
479 EXPORT_SYMBOL(__dfl_driver_register);
480
481 void dfl_driver_unregister(struct dfl_driver *dfl_drv)
482 {
483         driver_unregister(&dfl_drv->drv);
484 }
485 EXPORT_SYMBOL(dfl_driver_unregister);
486
487 #define is_header_feature(feature) ((feature)->id == FEATURE_ID_FIU_HEADER)
488
489 /**
490  * dfl_fpga_dev_feature_uinit - uinit for sub features of dfl feature device
491  * @pdev: feature device.
492  */
493 void dfl_fpga_dev_feature_uinit(struct platform_device *pdev)
494 {
495         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
496         struct dfl_feature *feature;
497
498         dfl_devs_remove(pdata);
499
500         dfl_fpga_dev_for_each_feature(pdata, feature) {
501                 if (feature->ops) {
502                         if (feature->ops->uinit)
503                                 feature->ops->uinit(pdev, feature);
504                         feature->ops = NULL;
505                 }
506         }
507 }
508 EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_uinit);
509
510 static int dfl_feature_instance_init(struct platform_device *pdev,
511                                      struct dfl_feature_platform_data *pdata,
512                                      struct dfl_feature *feature,
513                                      struct dfl_feature_driver *drv)
514 {
515         void __iomem *base;
516         int ret = 0;
517
518         if (!is_header_feature(feature)) {
519                 base = devm_platform_ioremap_resource(pdev,
520                                                       feature->resource_index);
521                 if (IS_ERR(base)) {
522                         dev_err(&pdev->dev,
523                                 "ioremap failed for feature 0x%x!\n",
524                                 feature->id);
525                         return PTR_ERR(base);
526                 }
527
528                 feature->ioaddr = base;
529         }
530
531         if (drv->ops->init) {
532                 ret = drv->ops->init(pdev, feature);
533                 if (ret)
534                         return ret;
535         }
536
537         feature->ops = drv->ops;
538
539         return ret;
540 }
541
542 static bool dfl_feature_drv_match(struct dfl_feature *feature,
543                                   struct dfl_feature_driver *driver)
544 {
545         const struct dfl_feature_id *ids = driver->id_table;
546
547         if (ids) {
548                 while (ids->id) {
549                         if (ids->id == feature->id)
550                                 return true;
551                         ids++;
552                 }
553         }
554         return false;
555 }
556
557 /**
558  * dfl_fpga_dev_feature_init - init for sub features of dfl feature device
559  * @pdev: feature device.
560  * @feature_drvs: drvs for sub features.
561  *
562  * This function will match sub features with given feature drvs list and
563  * use matched drv to init related sub feature.
564  *
565  * Return: 0 on success, negative error code otherwise.
566  */
567 int dfl_fpga_dev_feature_init(struct platform_device *pdev,
568                               struct dfl_feature_driver *feature_drvs)
569 {
570         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
571         struct dfl_feature_driver *drv = feature_drvs;
572         struct dfl_feature *feature;
573         int ret;
574
575         while (drv->ops) {
576                 dfl_fpga_dev_for_each_feature(pdata, feature) {
577                         if (dfl_feature_drv_match(feature, drv)) {
578                                 ret = dfl_feature_instance_init(pdev, pdata,
579                                                                 feature, drv);
580                                 if (ret)
581                                         goto exit;
582                         }
583                 }
584                 drv++;
585         }
586
587         ret = dfl_devs_add(pdata);
588         if (ret)
589                 goto exit;
590
591         return 0;
592 exit:
593         dfl_fpga_dev_feature_uinit(pdev);
594         return ret;
595 }
596 EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init);
597
598 static void dfl_chardev_uinit(void)
599 {
600         int i;
601
602         for (i = 0; i < DFL_FPGA_DEVT_MAX; i++)
603                 if (MAJOR(dfl_chrdevs[i].devt)) {
604                         unregister_chrdev_region(dfl_chrdevs[i].devt,
605                                                  MINORMASK + 1);
606                         dfl_chrdevs[i].devt = MKDEV(0, 0);
607                 }
608 }
609
610 static int dfl_chardev_init(void)
611 {
612         int i, ret;
613
614         for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) {
615                 ret = alloc_chrdev_region(&dfl_chrdevs[i].devt, 0,
616                                           MINORMASK + 1, dfl_chrdevs[i].name);
617                 if (ret)
618                         goto exit;
619         }
620
621         return 0;
622
623 exit:
624         dfl_chardev_uinit();
625         return ret;
626 }
627
628 static dev_t dfl_get_devt(enum dfl_fpga_devt_type type, int id)
629 {
630         if (type >= DFL_FPGA_DEVT_MAX)
631                 return 0;
632
633         return MKDEV(MAJOR(dfl_chrdevs[type].devt), id);
634 }
635
636 /**
637  * dfl_fpga_dev_ops_register - register cdev ops for feature dev
638  *
639  * @pdev: feature dev.
640  * @fops: file operations for feature dev's cdev.
641  * @owner: owning module/driver.
642  *
643  * Return: 0 on success, negative error code otherwise.
644  */
645 int dfl_fpga_dev_ops_register(struct platform_device *pdev,
646                               const struct file_operations *fops,
647                               struct module *owner)
648 {
649         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
650
651         cdev_init(&pdata->cdev, fops);
652         pdata->cdev.owner = owner;
653
654         /*
655          * set parent to the feature device so that its refcount is
656          * decreased after the last refcount of cdev is gone, that
657          * makes sure the feature device is valid during device
658          * file's life-cycle.
659          */
660         pdata->cdev.kobj.parent = &pdev->dev.kobj;
661
662         return cdev_add(&pdata->cdev, pdev->dev.devt, 1);
663 }
664 EXPORT_SYMBOL_GPL(dfl_fpga_dev_ops_register);
665
666 /**
667  * dfl_fpga_dev_ops_unregister - unregister cdev ops for feature dev
668  * @pdev: feature dev.
669  */
670 void dfl_fpga_dev_ops_unregister(struct platform_device *pdev)
671 {
672         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
673
674         cdev_del(&pdata->cdev);
675 }
676 EXPORT_SYMBOL_GPL(dfl_fpga_dev_ops_unregister);
677
678 /**
679  * struct build_feature_devs_info - info collected during feature dev build.
680  *
681  * @dev: device to enumerate.
682  * @cdev: the container device for all feature devices.
683  * @nr_irqs: number of irqs for all feature devices.
684  * @irq_table: Linux IRQ numbers for all irqs, indexed by local irq index of
685  *             this device.
686  * @feature_dev: current feature device.
687  * @ioaddr: header register region address of current FIU in enumeration.
688  * @start: register resource start of current FIU.
689  * @len: max register resource length of current FIU.
690  * @sub_features: a sub features linked list for feature device in enumeration.
691  * @feature_num: number of sub features for feature device in enumeration.
692  */
693 struct build_feature_devs_info {
694         struct device *dev;
695         struct dfl_fpga_cdev *cdev;
696         unsigned int nr_irqs;
697         int *irq_table;
698
699         struct platform_device *feature_dev;
700         void __iomem *ioaddr;
701         resource_size_t start;
702         resource_size_t len;
703         struct list_head sub_features;
704         int feature_num;
705 };
706
707 /**
708  * struct dfl_feature_info - sub feature info collected during feature dev build
709  *
710  * @fid: id of this sub feature.
711  * @mmio_res: mmio resource of this sub feature.
712  * @ioaddr: mapped base address of mmio resource.
713  * @node: node in sub_features linked list.
714  * @irq_base: start of irq index in this sub feature.
715  * @nr_irqs: number of irqs of this sub feature.
716  */
717 struct dfl_feature_info {
718         u16 fid;
719         u8 revision;
720         struct resource mmio_res;
721         void __iomem *ioaddr;
722         struct list_head node;
723         unsigned int irq_base;
724         unsigned int nr_irqs;
725 };
726
727 static void dfl_fpga_cdev_add_port_dev(struct dfl_fpga_cdev *cdev,
728                                        struct platform_device *port)
729 {
730         struct dfl_feature_platform_data *pdata = dev_get_platdata(&port->dev);
731
732         mutex_lock(&cdev->lock);
733         list_add(&pdata->node, &cdev->port_dev_list);
734         get_device(&pdata->dev->dev);
735         mutex_unlock(&cdev->lock);
736 }
737
738 /*
739  * register current feature device, it is called when we need to switch to
740  * another feature parsing or we have parsed all features on given device
741  * feature list.
742  */
743 static int build_info_commit_dev(struct build_feature_devs_info *binfo)
744 {
745         struct platform_device *fdev = binfo->feature_dev;
746         struct dfl_feature_platform_data *pdata;
747         struct dfl_feature_info *finfo, *p;
748         enum dfl_id_type type;
749         int ret, index = 0, res_idx = 0;
750
751         type = feature_dev_id_type(fdev);
752         if (WARN_ON_ONCE(type >= DFL_ID_MAX))
753                 return -EINVAL;
754
755         /*
756          * we do not need to care for the memory which is associated with
757          * the platform device. After calling platform_device_unregister(),
758          * it will be automatically freed by device's release() callback,
759          * platform_device_release().
760          */
761         pdata = kzalloc(struct_size(pdata, features, binfo->feature_num), GFP_KERNEL);
762         if (!pdata)
763                 return -ENOMEM;
764
765         pdata->dev = fdev;
766         pdata->num = binfo->feature_num;
767         pdata->dfl_cdev = binfo->cdev;
768         pdata->id = FEATURE_DEV_ID_UNUSED;
769         mutex_init(&pdata->lock);
770         lockdep_set_class_and_name(&pdata->lock, &dfl_pdata_keys[type],
771                                    dfl_pdata_key_strings[type]);
772
773         /*
774          * the count should be initialized to 0 to make sure
775          *__fpga_port_enable() following __fpga_port_disable()
776          * works properly for port device.
777          * and it should always be 0 for fme device.
778          */
779         WARN_ON(pdata->disable_count);
780
781         fdev->dev.platform_data = pdata;
782
783         /* each sub feature has one MMIO resource */
784         fdev->num_resources = binfo->feature_num;
785         fdev->resource = kcalloc(binfo->feature_num, sizeof(*fdev->resource),
786                                  GFP_KERNEL);
787         if (!fdev->resource)
788                 return -ENOMEM;
789
790         /* fill features and resource information for feature dev */
791         list_for_each_entry_safe(finfo, p, &binfo->sub_features, node) {
792                 struct dfl_feature *feature = &pdata->features[index++];
793                 struct dfl_feature_irq_ctx *ctx;
794                 unsigned int i;
795
796                 /* save resource information for each feature */
797                 feature->dev = fdev;
798                 feature->id = finfo->fid;
799                 feature->revision = finfo->revision;
800
801                 /*
802                  * the FIU header feature has some fundamental functions (sriov
803                  * set, port enable/disable) needed for the dfl bus device and
804                  * other sub features. So its mmio resource should be mapped by
805                  * DFL bus device. And we should not assign it to feature
806                  * devices (dfl-fme/afu) again.
807                  */
808                 if (is_header_feature(feature)) {
809                         feature->resource_index = -1;
810                         feature->ioaddr =
811                                 devm_ioremap_resource(binfo->dev,
812                                                       &finfo->mmio_res);
813                         if (IS_ERR(feature->ioaddr))
814                                 return PTR_ERR(feature->ioaddr);
815                 } else {
816                         feature->resource_index = res_idx;
817                         fdev->resource[res_idx++] = finfo->mmio_res;
818                 }
819
820                 if (finfo->nr_irqs) {
821                         ctx = devm_kcalloc(binfo->dev, finfo->nr_irqs,
822                                            sizeof(*ctx), GFP_KERNEL);
823                         if (!ctx)
824                                 return -ENOMEM;
825
826                         for (i = 0; i < finfo->nr_irqs; i++)
827                                 ctx[i].irq =
828                                         binfo->irq_table[finfo->irq_base + i];
829
830                         feature->irq_ctx = ctx;
831                         feature->nr_irqs = finfo->nr_irqs;
832                 }
833
834                 list_del(&finfo->node);
835                 kfree(finfo);
836         }
837
838         ret = platform_device_add(binfo->feature_dev);
839         if (!ret) {
840                 if (type == PORT_ID)
841                         dfl_fpga_cdev_add_port_dev(binfo->cdev,
842                                                    binfo->feature_dev);
843                 else
844                         binfo->cdev->fme_dev =
845                                         get_device(&binfo->feature_dev->dev);
846                 /*
847                  * reset it to avoid build_info_free() freeing their resource.
848                  *
849                  * The resource of successfully registered feature devices
850                  * will be freed by platform_device_unregister(). See the
851                  * comments in build_info_create_dev().
852                  */
853                 binfo->feature_dev = NULL;
854         }
855
856         return ret;
857 }
858
859 static int
860 build_info_create_dev(struct build_feature_devs_info *binfo,
861                       enum dfl_id_type type)
862 {
863         struct platform_device *fdev;
864
865         if (type >= DFL_ID_MAX)
866                 return -EINVAL;
867
868         /*
869          * we use -ENODEV as the initialization indicator which indicates
870          * whether the id need to be reclaimed
871          */
872         fdev = platform_device_alloc(dfl_devs[type].name, -ENODEV);
873         if (!fdev)
874                 return -ENOMEM;
875
876         binfo->feature_dev = fdev;
877         binfo->feature_num = 0;
878
879         INIT_LIST_HEAD(&binfo->sub_features);
880
881         fdev->id = dfl_id_alloc(type, &fdev->dev);
882         if (fdev->id < 0)
883                 return fdev->id;
884
885         fdev->dev.parent = &binfo->cdev->region->dev;
886         fdev->dev.devt = dfl_get_devt(dfl_devs[type].devt_type, fdev->id);
887
888         return 0;
889 }
890
891 static void build_info_free(struct build_feature_devs_info *binfo)
892 {
893         struct dfl_feature_info *finfo, *p;
894
895         /*
896          * it is a valid id, free it. See comments in
897          * build_info_create_dev()
898          */
899         if (binfo->feature_dev && binfo->feature_dev->id >= 0) {
900                 dfl_id_free(feature_dev_id_type(binfo->feature_dev),
901                             binfo->feature_dev->id);
902
903                 list_for_each_entry_safe(finfo, p, &binfo->sub_features, node) {
904                         list_del(&finfo->node);
905                         kfree(finfo);
906                 }
907         }
908
909         platform_device_put(binfo->feature_dev);
910
911         devm_kfree(binfo->dev, binfo);
912 }
913
914 static inline u32 feature_size(u64 value)
915 {
916         u32 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, value);
917         /* workaround for private features with invalid size, use 4K instead */
918         return ofst ? ofst : 4096;
919 }
920
921 static u16 feature_id(u64 value)
922 {
923         u16 id = FIELD_GET(DFH_ID, value);
924         u8 type = FIELD_GET(DFH_TYPE, value);
925
926         if (type == DFH_TYPE_FIU)
927                 return FEATURE_ID_FIU_HEADER;
928         else if (type == DFH_TYPE_PRIVATE)
929                 return id;
930         else if (type == DFH_TYPE_AFU)
931                 return FEATURE_ID_AFU;
932
933         WARN_ON(1);
934         return 0;
935 }
936
937 static int parse_feature_irqs(struct build_feature_devs_info *binfo,
938                               resource_size_t ofst, u16 fid,
939                               unsigned int *irq_base, unsigned int *nr_irqs)
940 {
941         void __iomem *base = binfo->ioaddr + ofst;
942         unsigned int i, ibase, inr = 0;
943         enum dfl_id_type type;
944         int virq;
945         u64 v;
946
947         type = feature_dev_id_type(binfo->feature_dev);
948
949         /*
950          * Ideally DFL framework should only read info from DFL header, but
951          * current version DFL only provides mmio resources information for
952          * each feature in DFL Header, no field for interrupt resources.
953          * Interrupt resource information is provided by specific mmio
954          * registers of each private feature which supports interrupt. So in
955          * order to parse and assign irq resources, DFL framework has to look
956          * into specific capability registers of these private features.
957          *
958          * Once future DFL version supports generic interrupt resource
959          * information in common DFL headers, the generic interrupt parsing
960          * code will be added. But in order to be compatible to old version
961          * DFL, the driver may still fall back to these quirks.
962          */
963         if (type == PORT_ID) {
964                 switch (fid) {
965                 case PORT_FEATURE_ID_UINT:
966                         v = readq(base + PORT_UINT_CAP);
967                         ibase = FIELD_GET(PORT_UINT_CAP_FST_VECT, v);
968                         inr = FIELD_GET(PORT_UINT_CAP_INT_NUM, v);
969                         break;
970                 case PORT_FEATURE_ID_ERROR:
971                         v = readq(base + PORT_ERROR_CAP);
972                         ibase = FIELD_GET(PORT_ERROR_CAP_INT_VECT, v);
973                         inr = FIELD_GET(PORT_ERROR_CAP_SUPP_INT, v);
974                         break;
975                 }
976         } else if (type == FME_ID) {
977                 if (fid == FME_FEATURE_ID_GLOBAL_ERR) {
978                         v = readq(base + FME_ERROR_CAP);
979                         ibase = FIELD_GET(FME_ERROR_CAP_INT_VECT, v);
980                         inr = FIELD_GET(FME_ERROR_CAP_SUPP_INT, v);
981                 }
982         }
983
984         if (!inr) {
985                 *irq_base = 0;
986                 *nr_irqs = 0;
987                 return 0;
988         }
989
990         dev_dbg(binfo->dev, "feature: 0x%x, irq_base: %u, nr_irqs: %u\n",
991                 fid, ibase, inr);
992
993         if (ibase + inr > binfo->nr_irqs) {
994                 dev_err(binfo->dev,
995                         "Invalid interrupt number in feature 0x%x\n", fid);
996                 return -EINVAL;
997         }
998
999         for (i = 0; i < inr; i++) {
1000                 virq = binfo->irq_table[ibase + i];
1001                 if (virq < 0 || virq > NR_IRQS) {
1002                         dev_err(binfo->dev,
1003                                 "Invalid irq table entry for feature 0x%x\n",
1004                                 fid);
1005                         return -EINVAL;
1006                 }
1007         }
1008
1009         *irq_base = ibase;
1010         *nr_irqs = inr;
1011
1012         return 0;
1013 }
1014
1015 /*
1016  * when create sub feature instances, for private features, it doesn't need
1017  * to provide resource size and feature id as they could be read from DFH
1018  * register. For afu sub feature, its register region only contains user
1019  * defined registers, so never trust any information from it, just use the
1020  * resource size information provided by its parent FIU.
1021  */
1022 static int
1023 create_feature_instance(struct build_feature_devs_info *binfo,
1024                         resource_size_t ofst, resource_size_t size, u16 fid)
1025 {
1026         unsigned int irq_base, nr_irqs;
1027         struct dfl_feature_info *finfo;
1028         u8 revision = 0;
1029         int ret;
1030         u64 v;
1031
1032         if (fid != FEATURE_ID_AFU) {
1033                 v = readq(binfo->ioaddr + ofst);
1034                 revision = FIELD_GET(DFH_REVISION, v);
1035
1036                 /* read feature size and id if inputs are invalid */
1037                 size = size ? size : feature_size(v);
1038                 fid = fid ? fid : feature_id(v);
1039         }
1040
1041         if (binfo->len - ofst < size)
1042                 return -EINVAL;
1043
1044         ret = parse_feature_irqs(binfo, ofst, fid, &irq_base, &nr_irqs);
1045         if (ret)
1046                 return ret;
1047
1048         finfo = kzalloc(sizeof(*finfo), GFP_KERNEL);
1049         if (!finfo)
1050                 return -ENOMEM;
1051
1052         finfo->fid = fid;
1053         finfo->revision = revision;
1054         finfo->mmio_res.start = binfo->start + ofst;
1055         finfo->mmio_res.end = finfo->mmio_res.start + size - 1;
1056         finfo->mmio_res.flags = IORESOURCE_MEM;
1057         finfo->irq_base = irq_base;
1058         finfo->nr_irqs = nr_irqs;
1059
1060         list_add_tail(&finfo->node, &binfo->sub_features);
1061         binfo->feature_num++;
1062
1063         return 0;
1064 }
1065
1066 static int parse_feature_port_afu(struct build_feature_devs_info *binfo,
1067                                   resource_size_t ofst)
1068 {
1069         u64 v = readq(binfo->ioaddr + PORT_HDR_CAP);
1070         u32 size = FIELD_GET(PORT_CAP_MMIO_SIZE, v) << 10;
1071
1072         WARN_ON(!size);
1073
1074         return create_feature_instance(binfo, ofst, size, FEATURE_ID_AFU);
1075 }
1076
1077 #define is_feature_dev_detected(binfo) (!!(binfo)->feature_dev)
1078
1079 static int parse_feature_afu(struct build_feature_devs_info *binfo,
1080                              resource_size_t ofst)
1081 {
1082         if (!is_feature_dev_detected(binfo)) {
1083                 dev_err(binfo->dev, "this AFU does not belong to any FIU.\n");
1084                 return -EINVAL;
1085         }
1086
1087         switch (feature_dev_id_type(binfo->feature_dev)) {
1088         case PORT_ID:
1089                 return parse_feature_port_afu(binfo, ofst);
1090         default:
1091                 dev_info(binfo->dev, "AFU belonging to FIU %s is not supported yet.\n",
1092                          binfo->feature_dev->name);
1093         }
1094
1095         return 0;
1096 }
1097
1098 static int build_info_prepare(struct build_feature_devs_info *binfo,
1099                               resource_size_t start, resource_size_t len)
1100 {
1101         struct device *dev = binfo->dev;
1102         void __iomem *ioaddr;
1103
1104         if (!devm_request_mem_region(dev, start, len, dev_name(dev))) {
1105                 dev_err(dev, "request region fail, start:%pa, len:%pa\n",
1106                         &start, &len);
1107                 return -EBUSY;
1108         }
1109
1110         ioaddr = devm_ioremap(dev, start, len);
1111         if (!ioaddr) {
1112                 dev_err(dev, "ioremap region fail, start:%pa, len:%pa\n",
1113                         &start, &len);
1114                 return -ENOMEM;
1115         }
1116
1117         binfo->start = start;
1118         binfo->len = len;
1119         binfo->ioaddr = ioaddr;
1120
1121         return 0;
1122 }
1123
1124 static void build_info_complete(struct build_feature_devs_info *binfo)
1125 {
1126         devm_iounmap(binfo->dev, binfo->ioaddr);
1127         devm_release_mem_region(binfo->dev, binfo->start, binfo->len);
1128 }
1129
1130 static int parse_feature_fiu(struct build_feature_devs_info *binfo,
1131                              resource_size_t ofst)
1132 {
1133         int ret = 0;
1134         u32 offset;
1135         u16 id;
1136         u64 v;
1137
1138         if (is_feature_dev_detected(binfo)) {
1139                 build_info_complete(binfo);
1140
1141                 ret = build_info_commit_dev(binfo);
1142                 if (ret)
1143                         return ret;
1144
1145                 ret = build_info_prepare(binfo, binfo->start + ofst,
1146                                          binfo->len - ofst);
1147                 if (ret)
1148                         return ret;
1149         }
1150
1151         v = readq(binfo->ioaddr + DFH);
1152         id = FIELD_GET(DFH_ID, v);
1153
1154         /* create platform device for dfl feature dev */
1155         ret = build_info_create_dev(binfo, dfh_id_to_type(id));
1156         if (ret)
1157                 return ret;
1158
1159         ret = create_feature_instance(binfo, 0, 0, 0);
1160         if (ret)
1161                 return ret;
1162         /*
1163          * find and parse FIU's child AFU via its NEXT_AFU register.
1164          * please note that only Port has valid NEXT_AFU pointer per spec.
1165          */
1166         v = readq(binfo->ioaddr + NEXT_AFU);
1167
1168         offset = FIELD_GET(NEXT_AFU_NEXT_DFH_OFST, v);
1169         if (offset)
1170                 return parse_feature_afu(binfo, offset);
1171
1172         dev_dbg(binfo->dev, "No AFUs detected on FIU %d\n", id);
1173
1174         return ret;
1175 }
1176
1177 static int parse_feature_private(struct build_feature_devs_info *binfo,
1178                                  resource_size_t ofst)
1179 {
1180         if (!is_feature_dev_detected(binfo)) {
1181                 dev_err(binfo->dev, "the private feature 0x%x does not belong to any AFU.\n",
1182                         feature_id(readq(binfo->ioaddr + ofst)));
1183                 return -EINVAL;
1184         }
1185
1186         return create_feature_instance(binfo, ofst, 0, 0);
1187 }
1188
1189 /**
1190  * parse_feature - parse a feature on given device feature list
1191  *
1192  * @binfo: build feature devices information.
1193  * @ofst: offset to current FIU header
1194  */
1195 static int parse_feature(struct build_feature_devs_info *binfo,
1196                          resource_size_t ofst)
1197 {
1198         u64 v;
1199         u32 type;
1200
1201         v = readq(binfo->ioaddr + ofst + DFH);
1202         type = FIELD_GET(DFH_TYPE, v);
1203
1204         switch (type) {
1205         case DFH_TYPE_AFU:
1206                 return parse_feature_afu(binfo, ofst);
1207         case DFH_TYPE_PRIVATE:
1208                 return parse_feature_private(binfo, ofst);
1209         case DFH_TYPE_FIU:
1210                 return parse_feature_fiu(binfo, ofst);
1211         default:
1212                 dev_info(binfo->dev,
1213                          "Feature Type %x is not supported.\n", type);
1214         }
1215
1216         return 0;
1217 }
1218
1219 static int parse_feature_list(struct build_feature_devs_info *binfo,
1220                               resource_size_t start, resource_size_t len)
1221 {
1222         resource_size_t end = start + len;
1223         int ret = 0;
1224         u32 ofst = 0;
1225         u64 v;
1226
1227         ret = build_info_prepare(binfo, start, len);
1228         if (ret)
1229                 return ret;
1230
1231         /* walk through the device feature list via DFH's next DFH pointer. */
1232         for (; start < end; start += ofst) {
1233                 if (end - start < DFH_SIZE) {
1234                         dev_err(binfo->dev, "The region is too small to contain a feature.\n");
1235                         return -EINVAL;
1236                 }
1237
1238                 ret = parse_feature(binfo, start - binfo->start);
1239                 if (ret)
1240                         return ret;
1241
1242                 v = readq(binfo->ioaddr + start - binfo->start + DFH);
1243                 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, v);
1244
1245                 /* stop parsing if EOL(End of List) is set or offset is 0 */
1246                 if ((v & DFH_EOL) || !ofst)
1247                         break;
1248         }
1249
1250         /* commit current feature device when reach the end of list */
1251         build_info_complete(binfo);
1252
1253         if (is_feature_dev_detected(binfo))
1254                 ret = build_info_commit_dev(binfo);
1255
1256         return ret;
1257 }
1258
1259 struct dfl_fpga_enum_info *dfl_fpga_enum_info_alloc(struct device *dev)
1260 {
1261         struct dfl_fpga_enum_info *info;
1262
1263         get_device(dev);
1264
1265         info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
1266         if (!info) {
1267                 put_device(dev);
1268                 return NULL;
1269         }
1270
1271         info->dev = dev;
1272         INIT_LIST_HEAD(&info->dfls);
1273
1274         return info;
1275 }
1276 EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_alloc);
1277
1278 void dfl_fpga_enum_info_free(struct dfl_fpga_enum_info *info)
1279 {
1280         struct dfl_fpga_enum_dfl *tmp, *dfl;
1281         struct device *dev;
1282
1283         if (!info)
1284                 return;
1285
1286         dev = info->dev;
1287
1288         /* remove all device feature lists in the list. */
1289         list_for_each_entry_safe(dfl, tmp, &info->dfls, node) {
1290                 list_del(&dfl->node);
1291                 devm_kfree(dev, dfl);
1292         }
1293
1294         /* remove irq table */
1295         if (info->irq_table)
1296                 devm_kfree(dev, info->irq_table);
1297
1298         devm_kfree(dev, info);
1299         put_device(dev);
1300 }
1301 EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_free);
1302
1303 /**
1304  * dfl_fpga_enum_info_add_dfl - add info of a device feature list to enum info
1305  *
1306  * @info: ptr to dfl_fpga_enum_info
1307  * @start: mmio resource address of the device feature list.
1308  * @len: mmio resource length of the device feature list.
1309  *
1310  * One FPGA device may have one or more Device Feature Lists (DFLs), use this
1311  * function to add information of each DFL to common data structure for next
1312  * step enumeration.
1313  *
1314  * Return: 0 on success, negative error code otherwise.
1315  */
1316 int dfl_fpga_enum_info_add_dfl(struct dfl_fpga_enum_info *info,
1317                                resource_size_t start, resource_size_t len)
1318 {
1319         struct dfl_fpga_enum_dfl *dfl;
1320
1321         dfl = devm_kzalloc(info->dev, sizeof(*dfl), GFP_KERNEL);
1322         if (!dfl)
1323                 return -ENOMEM;
1324
1325         dfl->start = start;
1326         dfl->len = len;
1327
1328         list_add_tail(&dfl->node, &info->dfls);
1329
1330         return 0;
1331 }
1332 EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_add_dfl);
1333
1334 /**
1335  * dfl_fpga_enum_info_add_irq - add irq table to enum info
1336  *
1337  * @info: ptr to dfl_fpga_enum_info
1338  * @nr_irqs: number of irqs of the DFL fpga device to be enumerated.
1339  * @irq_table: Linux IRQ numbers for all irqs, indexed by local irq index of
1340  *             this device.
1341  *
1342  * One FPGA device may have several interrupts. This function adds irq
1343  * information of the DFL fpga device to enum info for next step enumeration.
1344  * This function should be called before dfl_fpga_feature_devs_enumerate().
1345  * As we only support one irq domain for all DFLs in the same enum info, adding
1346  * irq table a second time for the same enum info will return error.
1347  *
1348  * If we need to enumerate DFLs which belong to different irq domains, we
1349  * should fill more enum info and enumerate them one by one.
1350  *
1351  * Return: 0 on success, negative error code otherwise.
1352  */
1353 int dfl_fpga_enum_info_add_irq(struct dfl_fpga_enum_info *info,
1354                                unsigned int nr_irqs, int *irq_table)
1355 {
1356         if (!nr_irqs || !irq_table)
1357                 return -EINVAL;
1358
1359         if (info->irq_table)
1360                 return -EEXIST;
1361
1362         info->irq_table = devm_kmemdup(info->dev, irq_table,
1363                                        sizeof(int) * nr_irqs, GFP_KERNEL);
1364         if (!info->irq_table)
1365                 return -ENOMEM;
1366
1367         info->nr_irqs = nr_irqs;
1368
1369         return 0;
1370 }
1371 EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_add_irq);
1372
1373 static int remove_feature_dev(struct device *dev, void *data)
1374 {
1375         struct platform_device *pdev = to_platform_device(dev);
1376         enum dfl_id_type type = feature_dev_id_type(pdev);
1377         int id = pdev->id;
1378
1379         platform_device_unregister(pdev);
1380
1381         dfl_id_free(type, id);
1382
1383         return 0;
1384 }
1385
1386 static void remove_feature_devs(struct dfl_fpga_cdev *cdev)
1387 {
1388         device_for_each_child(&cdev->region->dev, NULL, remove_feature_dev);
1389 }
1390
1391 /**
1392  * dfl_fpga_feature_devs_enumerate - enumerate feature devices
1393  * @info: information for enumeration.
1394  *
1395  * This function creates a container device (base FPGA region), enumerates
1396  * feature devices based on the enumeration info and creates platform devices
1397  * under the container device.
1398  *
1399  * Return: dfl_fpga_cdev struct on success, -errno on failure
1400  */
1401 struct dfl_fpga_cdev *
1402 dfl_fpga_feature_devs_enumerate(struct dfl_fpga_enum_info *info)
1403 {
1404         struct build_feature_devs_info *binfo;
1405         struct dfl_fpga_enum_dfl *dfl;
1406         struct dfl_fpga_cdev *cdev;
1407         int ret = 0;
1408
1409         if (!info->dev)
1410                 return ERR_PTR(-ENODEV);
1411
1412         cdev = devm_kzalloc(info->dev, sizeof(*cdev), GFP_KERNEL);
1413         if (!cdev)
1414                 return ERR_PTR(-ENOMEM);
1415
1416         cdev->parent = info->dev;
1417         mutex_init(&cdev->lock);
1418         INIT_LIST_HEAD(&cdev->port_dev_list);
1419
1420         cdev->region = fpga_region_register(info->dev, NULL, NULL);
1421         if (IS_ERR(cdev->region)) {
1422                 ret = PTR_ERR(cdev->region);
1423                 goto free_cdev_exit;
1424         }
1425
1426         /* create and init build info for enumeration */
1427         binfo = devm_kzalloc(info->dev, sizeof(*binfo), GFP_KERNEL);
1428         if (!binfo) {
1429                 ret = -ENOMEM;
1430                 goto unregister_region_exit;
1431         }
1432
1433         binfo->dev = info->dev;
1434         binfo->cdev = cdev;
1435
1436         binfo->nr_irqs = info->nr_irqs;
1437         if (info->nr_irqs)
1438                 binfo->irq_table = info->irq_table;
1439
1440         /*
1441          * start enumeration for all feature devices based on Device Feature
1442          * Lists.
1443          */
1444         list_for_each_entry(dfl, &info->dfls, node) {
1445                 ret = parse_feature_list(binfo, dfl->start, dfl->len);
1446                 if (ret) {
1447                         remove_feature_devs(cdev);
1448                         build_info_free(binfo);
1449                         goto unregister_region_exit;
1450                 }
1451         }
1452
1453         build_info_free(binfo);
1454
1455         return cdev;
1456
1457 unregister_region_exit:
1458         fpga_region_unregister(cdev->region);
1459 free_cdev_exit:
1460         devm_kfree(info->dev, cdev);
1461         return ERR_PTR(ret);
1462 }
1463 EXPORT_SYMBOL_GPL(dfl_fpga_feature_devs_enumerate);
1464
1465 /**
1466  * dfl_fpga_feature_devs_remove - remove all feature devices
1467  * @cdev: fpga container device.
1468  *
1469  * Remove the container device and all feature devices under given container
1470  * devices.
1471  */
1472 void dfl_fpga_feature_devs_remove(struct dfl_fpga_cdev *cdev)
1473 {
1474         struct dfl_feature_platform_data *pdata, *ptmp;
1475
1476         mutex_lock(&cdev->lock);
1477         if (cdev->fme_dev)
1478                 put_device(cdev->fme_dev);
1479
1480         list_for_each_entry_safe(pdata, ptmp, &cdev->port_dev_list, node) {
1481                 struct platform_device *port_dev = pdata->dev;
1482
1483                 /* remove released ports */
1484                 if (!device_is_registered(&port_dev->dev)) {
1485                         dfl_id_free(feature_dev_id_type(port_dev),
1486                                     port_dev->id);
1487                         platform_device_put(port_dev);
1488                 }
1489
1490                 list_del(&pdata->node);
1491                 put_device(&port_dev->dev);
1492         }
1493         mutex_unlock(&cdev->lock);
1494
1495         remove_feature_devs(cdev);
1496
1497         fpga_region_unregister(cdev->region);
1498         devm_kfree(cdev->parent, cdev);
1499 }
1500 EXPORT_SYMBOL_GPL(dfl_fpga_feature_devs_remove);
1501
1502 /**
1503  * __dfl_fpga_cdev_find_port - find a port under given container device
1504  *
1505  * @cdev: container device
1506  * @data: data passed to match function
1507  * @match: match function used to find specific port from the port device list
1508  *
1509  * Find a port device under container device. This function needs to be
1510  * invoked with lock held.
1511  *
1512  * Return: pointer to port's platform device if successful, NULL otherwise.
1513  *
1514  * NOTE: you will need to drop the device reference with put_device() after use.
1515  */
1516 struct platform_device *
1517 __dfl_fpga_cdev_find_port(struct dfl_fpga_cdev *cdev, void *data,
1518                           int (*match)(struct platform_device *, void *))
1519 {
1520         struct dfl_feature_platform_data *pdata;
1521         struct platform_device *port_dev;
1522
1523         list_for_each_entry(pdata, &cdev->port_dev_list, node) {
1524                 port_dev = pdata->dev;
1525
1526                 if (match(port_dev, data) && get_device(&port_dev->dev))
1527                         return port_dev;
1528         }
1529
1530         return NULL;
1531 }
1532 EXPORT_SYMBOL_GPL(__dfl_fpga_cdev_find_port);
1533
1534 static int __init dfl_fpga_init(void)
1535 {
1536         int ret;
1537
1538         ret = bus_register(&dfl_bus_type);
1539         if (ret)
1540                 return ret;
1541
1542         dfl_ids_init();
1543
1544         ret = dfl_chardev_init();
1545         if (ret) {
1546                 dfl_ids_destroy();
1547                 bus_unregister(&dfl_bus_type);
1548         }
1549
1550         return ret;
1551 }
1552
1553 /**
1554  * dfl_fpga_cdev_release_port - release a port platform device
1555  *
1556  * @cdev: parent container device.
1557  * @port_id: id of the port platform device.
1558  *
1559  * This function allows user to release a port platform device. This is a
1560  * mandatory step before turn a port from PF into VF for SRIOV support.
1561  *
1562  * Return: 0 on success, negative error code otherwise.
1563  */
1564 int dfl_fpga_cdev_release_port(struct dfl_fpga_cdev *cdev, int port_id)
1565 {
1566         struct dfl_feature_platform_data *pdata;
1567         struct platform_device *port_pdev;
1568         int ret = -ENODEV;
1569
1570         mutex_lock(&cdev->lock);
1571         port_pdev = __dfl_fpga_cdev_find_port(cdev, &port_id,
1572                                               dfl_fpga_check_port_id);
1573         if (!port_pdev)
1574                 goto unlock_exit;
1575
1576         if (!device_is_registered(&port_pdev->dev)) {
1577                 ret = -EBUSY;
1578                 goto put_dev_exit;
1579         }
1580
1581         pdata = dev_get_platdata(&port_pdev->dev);
1582
1583         mutex_lock(&pdata->lock);
1584         ret = dfl_feature_dev_use_begin(pdata, true);
1585         mutex_unlock(&pdata->lock);
1586         if (ret)
1587                 goto put_dev_exit;
1588
1589         platform_device_del(port_pdev);
1590         cdev->released_port_num++;
1591 put_dev_exit:
1592         put_device(&port_pdev->dev);
1593 unlock_exit:
1594         mutex_unlock(&cdev->lock);
1595         return ret;
1596 }
1597 EXPORT_SYMBOL_GPL(dfl_fpga_cdev_release_port);
1598
1599 /**
1600  * dfl_fpga_cdev_assign_port - assign a port platform device back
1601  *
1602  * @cdev: parent container device.
1603  * @port_id: id of the port platform device.
1604  *
1605  * This function allows user to assign a port platform device back. This is
1606  * a mandatory step after disable SRIOV support.
1607  *
1608  * Return: 0 on success, negative error code otherwise.
1609  */
1610 int dfl_fpga_cdev_assign_port(struct dfl_fpga_cdev *cdev, int port_id)
1611 {
1612         struct dfl_feature_platform_data *pdata;
1613         struct platform_device *port_pdev;
1614         int ret = -ENODEV;
1615
1616         mutex_lock(&cdev->lock);
1617         port_pdev = __dfl_fpga_cdev_find_port(cdev, &port_id,
1618                                               dfl_fpga_check_port_id);
1619         if (!port_pdev)
1620                 goto unlock_exit;
1621
1622         if (device_is_registered(&port_pdev->dev)) {
1623                 ret = -EBUSY;
1624                 goto put_dev_exit;
1625         }
1626
1627         ret = platform_device_add(port_pdev);
1628         if (ret)
1629                 goto put_dev_exit;
1630
1631         pdata = dev_get_platdata(&port_pdev->dev);
1632
1633         mutex_lock(&pdata->lock);
1634         dfl_feature_dev_use_end(pdata);
1635         mutex_unlock(&pdata->lock);
1636
1637         cdev->released_port_num--;
1638 put_dev_exit:
1639         put_device(&port_pdev->dev);
1640 unlock_exit:
1641         mutex_unlock(&cdev->lock);
1642         return ret;
1643 }
1644 EXPORT_SYMBOL_GPL(dfl_fpga_cdev_assign_port);
1645
1646 static void config_port_access_mode(struct device *fme_dev, int port_id,
1647                                     bool is_vf)
1648 {
1649         void __iomem *base;
1650         u64 v;
1651
1652         base = dfl_get_feature_ioaddr_by_id(fme_dev, FME_FEATURE_ID_HEADER);
1653
1654         v = readq(base + FME_HDR_PORT_OFST(port_id));
1655
1656         v &= ~FME_PORT_OFST_ACC_CTRL;
1657         v |= FIELD_PREP(FME_PORT_OFST_ACC_CTRL,
1658                         is_vf ? FME_PORT_OFST_ACC_VF : FME_PORT_OFST_ACC_PF);
1659
1660         writeq(v, base + FME_HDR_PORT_OFST(port_id));
1661 }
1662
1663 #define config_port_vf_mode(dev, id) config_port_access_mode(dev, id, true)
1664 #define config_port_pf_mode(dev, id) config_port_access_mode(dev, id, false)
1665
1666 /**
1667  * dfl_fpga_cdev_config_ports_pf - configure ports to PF access mode
1668  *
1669  * @cdev: parent container device.
1670  *
1671  * This function is needed in sriov configuration routine. It could be used to
1672  * configure the all released ports from VF access mode to PF.
1673  */
1674 void dfl_fpga_cdev_config_ports_pf(struct dfl_fpga_cdev *cdev)
1675 {
1676         struct dfl_feature_platform_data *pdata;
1677
1678         mutex_lock(&cdev->lock);
1679         list_for_each_entry(pdata, &cdev->port_dev_list, node) {
1680                 if (device_is_registered(&pdata->dev->dev))
1681                         continue;
1682
1683                 config_port_pf_mode(cdev->fme_dev, pdata->id);
1684         }
1685         mutex_unlock(&cdev->lock);
1686 }
1687 EXPORT_SYMBOL_GPL(dfl_fpga_cdev_config_ports_pf);
1688
1689 /**
1690  * dfl_fpga_cdev_config_ports_vf - configure ports to VF access mode
1691  *
1692  * @cdev: parent container device.
1693  * @num_vfs: VF device number.
1694  *
1695  * This function is needed in sriov configuration routine. It could be used to
1696  * configure the released ports from PF access mode to VF.
1697  *
1698  * Return: 0 on success, negative error code otherwise.
1699  */
1700 int dfl_fpga_cdev_config_ports_vf(struct dfl_fpga_cdev *cdev, int num_vfs)
1701 {
1702         struct dfl_feature_platform_data *pdata;
1703         int ret = 0;
1704
1705         mutex_lock(&cdev->lock);
1706         /*
1707          * can't turn multiple ports into 1 VF device, only 1 port for 1 VF
1708          * device, so if released port number doesn't match VF device number,
1709          * then reject the request with -EINVAL error code.
1710          */
1711         if (cdev->released_port_num != num_vfs) {
1712                 ret = -EINVAL;
1713                 goto done;
1714         }
1715
1716         list_for_each_entry(pdata, &cdev->port_dev_list, node) {
1717                 if (device_is_registered(&pdata->dev->dev))
1718                         continue;
1719
1720                 config_port_vf_mode(cdev->fme_dev, pdata->id);
1721         }
1722 done:
1723         mutex_unlock(&cdev->lock);
1724         return ret;
1725 }
1726 EXPORT_SYMBOL_GPL(dfl_fpga_cdev_config_ports_vf);
1727
1728 static irqreturn_t dfl_irq_handler(int irq, void *arg)
1729 {
1730         struct eventfd_ctx *trigger = arg;
1731
1732         eventfd_signal(trigger, 1);
1733         return IRQ_HANDLED;
1734 }
1735
1736 static int do_set_irq_trigger(struct dfl_feature *feature, unsigned int idx,
1737                               int fd)
1738 {
1739         struct platform_device *pdev = feature->dev;
1740         struct eventfd_ctx *trigger;
1741         int irq, ret;
1742
1743         irq = feature->irq_ctx[idx].irq;
1744
1745         if (feature->irq_ctx[idx].trigger) {
1746                 free_irq(irq, feature->irq_ctx[idx].trigger);
1747                 kfree(feature->irq_ctx[idx].name);
1748                 eventfd_ctx_put(feature->irq_ctx[idx].trigger);
1749                 feature->irq_ctx[idx].trigger = NULL;
1750         }
1751
1752         if (fd < 0)
1753                 return 0;
1754
1755         feature->irq_ctx[idx].name =
1756                 kasprintf(GFP_KERNEL, "fpga-irq[%u](%s-%x)", idx,
1757                           dev_name(&pdev->dev), feature->id);
1758         if (!feature->irq_ctx[idx].name)
1759                 return -ENOMEM;
1760
1761         trigger = eventfd_ctx_fdget(fd);
1762         if (IS_ERR(trigger)) {
1763                 ret = PTR_ERR(trigger);
1764                 goto free_name;
1765         }
1766
1767         ret = request_irq(irq, dfl_irq_handler, 0,
1768                           feature->irq_ctx[idx].name, trigger);
1769         if (!ret) {
1770                 feature->irq_ctx[idx].trigger = trigger;
1771                 return ret;
1772         }
1773
1774         eventfd_ctx_put(trigger);
1775 free_name:
1776         kfree(feature->irq_ctx[idx].name);
1777
1778         return ret;
1779 }
1780
1781 /**
1782  * dfl_fpga_set_irq_triggers - set eventfd triggers for dfl feature interrupts
1783  *
1784  * @feature: dfl sub feature.
1785  * @start: start of irq index in this dfl sub feature.
1786  * @count: number of irqs.
1787  * @fds: eventfds to bind with irqs. unbind related irq if fds[n] is negative.
1788  *       unbind "count" specified number of irqs if fds ptr is NULL.
1789  *
1790  * Bind given eventfds with irqs in this dfl sub feature. Unbind related irq if
1791  * fds[n] is negative. Unbind "count" specified number of irqs if fds ptr is
1792  * NULL.
1793  *
1794  * Return: 0 on success, negative error code otherwise.
1795  */
1796 int dfl_fpga_set_irq_triggers(struct dfl_feature *feature, unsigned int start,
1797                               unsigned int count, int32_t *fds)
1798 {
1799         unsigned int i;
1800         int ret = 0;
1801
1802         /* overflow */
1803         if (unlikely(start + count < start))
1804                 return -EINVAL;
1805
1806         /* exceeds nr_irqs */
1807         if (start + count > feature->nr_irqs)
1808                 return -EINVAL;
1809
1810         for (i = 0; i < count; i++) {
1811                 int fd = fds ? fds[i] : -1;
1812
1813                 ret = do_set_irq_trigger(feature, start + i, fd);
1814                 if (ret) {
1815                         while (i--)
1816                                 do_set_irq_trigger(feature, start + i, -1);
1817                         break;
1818                 }
1819         }
1820
1821         return ret;
1822 }
1823 EXPORT_SYMBOL_GPL(dfl_fpga_set_irq_triggers);
1824
1825 /**
1826  * dfl_feature_ioctl_get_num_irqs - dfl feature _GET_IRQ_NUM ioctl interface.
1827  * @pdev: the feature device which has the sub feature
1828  * @feature: the dfl sub feature
1829  * @arg: ioctl argument
1830  *
1831  * Return: 0 on success, negative error code otherwise.
1832  */
1833 long dfl_feature_ioctl_get_num_irqs(struct platform_device *pdev,
1834                                     struct dfl_feature *feature,
1835                                     unsigned long arg)
1836 {
1837         return put_user(feature->nr_irqs, (__u32 __user *)arg);
1838 }
1839 EXPORT_SYMBOL_GPL(dfl_feature_ioctl_get_num_irqs);
1840
1841 /**
1842  * dfl_feature_ioctl_set_irq - dfl feature _SET_IRQ ioctl interface.
1843  * @pdev: the feature device which has the sub feature
1844  * @feature: the dfl sub feature
1845  * @arg: ioctl argument
1846  *
1847  * Return: 0 on success, negative error code otherwise.
1848  */
1849 long dfl_feature_ioctl_set_irq(struct platform_device *pdev,
1850                                struct dfl_feature *feature,
1851                                unsigned long arg)
1852 {
1853         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
1854         struct dfl_fpga_irq_set hdr;
1855         s32 *fds;
1856         long ret;
1857
1858         if (!feature->nr_irqs)
1859                 return -ENOENT;
1860
1861         if (copy_from_user(&hdr, (void __user *)arg, sizeof(hdr)))
1862                 return -EFAULT;
1863
1864         if (!hdr.count || (hdr.start + hdr.count > feature->nr_irqs) ||
1865             (hdr.start + hdr.count < hdr.start))
1866                 return -EINVAL;
1867
1868         fds = memdup_user((void __user *)(arg + sizeof(hdr)),
1869                           array_size(hdr.count, sizeof(s32)));
1870         if (IS_ERR(fds))
1871                 return PTR_ERR(fds);
1872
1873         mutex_lock(&pdata->lock);
1874         ret = dfl_fpga_set_irq_triggers(feature, hdr.start, hdr.count, fds);
1875         mutex_unlock(&pdata->lock);
1876
1877         kfree(fds);
1878         return ret;
1879 }
1880 EXPORT_SYMBOL_GPL(dfl_feature_ioctl_set_irq);
1881
1882 static void __exit dfl_fpga_exit(void)
1883 {
1884         dfl_chardev_uinit();
1885         dfl_ids_destroy();
1886         bus_unregister(&dfl_bus_type);
1887 }
1888
1889 module_init(dfl_fpga_init);
1890 module_exit(dfl_fpga_exit);
1891
1892 MODULE_DESCRIPTION("FPGA Device Feature List (DFL) Support");
1893 MODULE_AUTHOR("Intel Corporation");
1894 MODULE_LICENSE("GPL v2");