GNU Linux-libre 4.19.268-gnu1
[releases.git] / drivers / s390 / net / ism_drv.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ISM driver for s390.
4  *
5  * Copyright IBM Corp. 2018
6  */
7 #define KMSG_COMPONENT "ism"
8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9
10 #include <linux/module.h>
11 #include <linux/types.h>
12 #include <linux/interrupt.h>
13 #include <linux/device.h>
14 #include <linux/pci.h>
15 #include <linux/err.h>
16 #include <net/smc.h>
17
18 #include <asm/debug.h>
19
20 #include "ism.h"
21
22 MODULE_DESCRIPTION("ISM driver for s390");
23 MODULE_LICENSE("GPL");
24
25 #define PCI_DEVICE_ID_IBM_ISM 0x04ED
26 #define DRV_NAME "ism"
27
28 static const struct pci_device_id ism_device_table[] = {
29         { PCI_VDEVICE(IBM, PCI_DEVICE_ID_IBM_ISM), 0 },
30         { 0, }
31 };
32 MODULE_DEVICE_TABLE(pci, ism_device_table);
33
34 static debug_info_t *ism_debug_info;
35
36 static int ism_cmd(struct ism_dev *ism, void *cmd)
37 {
38         struct ism_req_hdr *req = cmd;
39         struct ism_resp_hdr *resp = cmd;
40
41         memcpy_toio(ism->ctl + sizeof(*req), req + 1, req->len - sizeof(*req));
42         memcpy_toio(ism->ctl, req, sizeof(*req));
43
44         WRITE_ONCE(resp->ret, ISM_ERROR);
45
46         memcpy_fromio(resp, ism->ctl, sizeof(*resp));
47         if (resp->ret) {
48                 debug_text_event(ism_debug_info, 0, "cmd failure");
49                 debug_event(ism_debug_info, 0, resp, sizeof(*resp));
50                 goto out;
51         }
52         memcpy_fromio(resp + 1, ism->ctl + sizeof(*resp),
53                       resp->len - sizeof(*resp));
54 out:
55         return resp->ret;
56 }
57
58 static int ism_cmd_simple(struct ism_dev *ism, u32 cmd_code)
59 {
60         union ism_cmd_simple cmd;
61
62         memset(&cmd, 0, sizeof(cmd));
63         cmd.request.hdr.cmd = cmd_code;
64         cmd.request.hdr.len = sizeof(cmd.request);
65
66         return ism_cmd(ism, &cmd);
67 }
68
69 static int query_info(struct ism_dev *ism)
70 {
71         union ism_qi cmd;
72
73         memset(&cmd, 0, sizeof(cmd));
74         cmd.request.hdr.cmd = ISM_QUERY_INFO;
75         cmd.request.hdr.len = sizeof(cmd.request);
76
77         if (ism_cmd(ism, &cmd))
78                 goto out;
79
80         debug_text_event(ism_debug_info, 3, "query info");
81         debug_event(ism_debug_info, 3, &cmd.response, sizeof(cmd.response));
82 out:
83         return 0;
84 }
85
86 static int register_sba(struct ism_dev *ism)
87 {
88         union ism_reg_sba cmd;
89         dma_addr_t dma_handle;
90         struct ism_sba *sba;
91
92         sba = dma_zalloc_coherent(&ism->pdev->dev, PAGE_SIZE,
93                                   &dma_handle, GFP_KERNEL);
94         if (!sba)
95                 return -ENOMEM;
96
97         memset(&cmd, 0, sizeof(cmd));
98         cmd.request.hdr.cmd = ISM_REG_SBA;
99         cmd.request.hdr.len = sizeof(cmd.request);
100         cmd.request.sba = dma_handle;
101
102         if (ism_cmd(ism, &cmd)) {
103                 dma_free_coherent(&ism->pdev->dev, PAGE_SIZE, sba, dma_handle);
104                 return -EIO;
105         }
106
107         ism->sba = sba;
108         ism->sba_dma_addr = dma_handle;
109
110         return 0;
111 }
112
113 static int register_ieq(struct ism_dev *ism)
114 {
115         union ism_reg_ieq cmd;
116         dma_addr_t dma_handle;
117         struct ism_eq *ieq;
118
119         ieq = dma_zalloc_coherent(&ism->pdev->dev, PAGE_SIZE,
120                                   &dma_handle, GFP_KERNEL);
121         if (!ieq)
122                 return -ENOMEM;
123
124         memset(&cmd, 0, sizeof(cmd));
125         cmd.request.hdr.cmd = ISM_REG_IEQ;
126         cmd.request.hdr.len = sizeof(cmd.request);
127         cmd.request.ieq = dma_handle;
128         cmd.request.len = sizeof(*ieq);
129
130         if (ism_cmd(ism, &cmd)) {
131                 dma_free_coherent(&ism->pdev->dev, PAGE_SIZE, ieq, dma_handle);
132                 return -EIO;
133         }
134
135         ism->ieq = ieq;
136         ism->ieq_idx = -1;
137         ism->ieq_dma_addr = dma_handle;
138
139         return 0;
140 }
141
142 static int unregister_sba(struct ism_dev *ism)
143 {
144         int ret;
145
146         if (!ism->sba)
147                 return 0;
148
149         ret = ism_cmd_simple(ism, ISM_UNREG_SBA);
150         if (ret && ret != ISM_ERROR)
151                 return -EIO;
152
153         dma_free_coherent(&ism->pdev->dev, PAGE_SIZE,
154                           ism->sba, ism->sba_dma_addr);
155
156         ism->sba = NULL;
157         ism->sba_dma_addr = 0;
158
159         return 0;
160 }
161
162 static int unregister_ieq(struct ism_dev *ism)
163 {
164         int ret;
165
166         if (!ism->ieq)
167                 return 0;
168
169         ret = ism_cmd_simple(ism, ISM_UNREG_IEQ);
170         if (ret && ret != ISM_ERROR)
171                 return -EIO;
172
173         dma_free_coherent(&ism->pdev->dev, PAGE_SIZE,
174                           ism->ieq, ism->ieq_dma_addr);
175
176         ism->ieq = NULL;
177         ism->ieq_dma_addr = 0;
178
179         return 0;
180 }
181
182 static int ism_read_local_gid(struct ism_dev *ism)
183 {
184         union ism_read_gid cmd;
185         int ret;
186
187         memset(&cmd, 0, sizeof(cmd));
188         cmd.request.hdr.cmd = ISM_READ_GID;
189         cmd.request.hdr.len = sizeof(cmd.request);
190
191         ret = ism_cmd(ism, &cmd);
192         if (ret)
193                 goto out;
194
195         ism->smcd->local_gid = cmd.response.gid;
196 out:
197         return ret;
198 }
199
200 static int ism_query_rgid(struct smcd_dev *smcd, u64 rgid, u32 vid_valid,
201                           u32 vid)
202 {
203         struct ism_dev *ism = smcd->priv;
204         union ism_query_rgid cmd;
205
206         memset(&cmd, 0, sizeof(cmd));
207         cmd.request.hdr.cmd = ISM_QUERY_RGID;
208         cmd.request.hdr.len = sizeof(cmd.request);
209
210         cmd.request.rgid = rgid;
211         cmd.request.vlan_valid = vid_valid;
212         cmd.request.vlan_id = vid;
213
214         return ism_cmd(ism, &cmd);
215 }
216
217 static void ism_free_dmb(struct ism_dev *ism, struct smcd_dmb *dmb)
218 {
219         clear_bit(dmb->sba_idx, ism->sba_bitmap);
220         dma_free_coherent(&ism->pdev->dev, dmb->dmb_len,
221                           dmb->cpu_addr, dmb->dma_addr);
222 }
223
224 static int ism_alloc_dmb(struct ism_dev *ism, struct smcd_dmb *dmb)
225 {
226         unsigned long bit;
227
228         if (PAGE_ALIGN(dmb->dmb_len) > dma_get_max_seg_size(&ism->pdev->dev))
229                 return -EINVAL;
230
231         if (!dmb->sba_idx) {
232                 bit = find_next_zero_bit(ism->sba_bitmap, ISM_NR_DMBS,
233                                          ISM_DMB_BIT_OFFSET);
234                 if (bit == ISM_NR_DMBS)
235                         return -ENOMEM;
236
237                 dmb->sba_idx = bit;
238         }
239         if (dmb->sba_idx < ISM_DMB_BIT_OFFSET ||
240             test_and_set_bit(dmb->sba_idx, ism->sba_bitmap))
241                 return -EINVAL;
242
243         dmb->cpu_addr = dma_zalloc_coherent(&ism->pdev->dev, dmb->dmb_len,
244                                             &dmb->dma_addr, GFP_KERNEL |
245                                             __GFP_NOWARN | __GFP_NOMEMALLOC |
246                                             __GFP_COMP | __GFP_NORETRY);
247         if (!dmb->cpu_addr)
248                 clear_bit(dmb->sba_idx, ism->sba_bitmap);
249
250         return dmb->cpu_addr ? 0 : -ENOMEM;
251 }
252
253 static int ism_register_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
254 {
255         struct ism_dev *ism = smcd->priv;
256         union ism_reg_dmb cmd;
257         int ret;
258
259         ret = ism_alloc_dmb(ism, dmb);
260         if (ret)
261                 goto out;
262
263         memset(&cmd, 0, sizeof(cmd));
264         cmd.request.hdr.cmd = ISM_REG_DMB;
265         cmd.request.hdr.len = sizeof(cmd.request);
266
267         cmd.request.dmb = dmb->dma_addr;
268         cmd.request.dmb_len = dmb->dmb_len;
269         cmd.request.sba_idx = dmb->sba_idx;
270         cmd.request.vlan_valid = dmb->vlan_valid;
271         cmd.request.vlan_id = dmb->vlan_id;
272         cmd.request.rgid = dmb->rgid;
273
274         ret = ism_cmd(ism, &cmd);
275         if (ret) {
276                 ism_free_dmb(ism, dmb);
277                 goto out;
278         }
279         dmb->dmb_tok = cmd.response.dmb_tok;
280 out:
281         return ret;
282 }
283
284 static int ism_unregister_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
285 {
286         struct ism_dev *ism = smcd->priv;
287         union ism_unreg_dmb cmd;
288         int ret;
289
290         memset(&cmd, 0, sizeof(cmd));
291         cmd.request.hdr.cmd = ISM_UNREG_DMB;
292         cmd.request.hdr.len = sizeof(cmd.request);
293
294         cmd.request.dmb_tok = dmb->dmb_tok;
295
296         ret = ism_cmd(ism, &cmd);
297         if (ret && ret != ISM_ERROR)
298                 goto out;
299
300         ism_free_dmb(ism, dmb);
301 out:
302         return ret;
303 }
304
305 static int ism_add_vlan_id(struct smcd_dev *smcd, u64 vlan_id)
306 {
307         struct ism_dev *ism = smcd->priv;
308         union ism_set_vlan_id cmd;
309
310         memset(&cmd, 0, sizeof(cmd));
311         cmd.request.hdr.cmd = ISM_ADD_VLAN_ID;
312         cmd.request.hdr.len = sizeof(cmd.request);
313
314         cmd.request.vlan_id = vlan_id;
315
316         return ism_cmd(ism, &cmd);
317 }
318
319 static int ism_del_vlan_id(struct smcd_dev *smcd, u64 vlan_id)
320 {
321         struct ism_dev *ism = smcd->priv;
322         union ism_set_vlan_id cmd;
323
324         memset(&cmd, 0, sizeof(cmd));
325         cmd.request.hdr.cmd = ISM_DEL_VLAN_ID;
326         cmd.request.hdr.len = sizeof(cmd.request);
327
328         cmd.request.vlan_id = vlan_id;
329
330         return ism_cmd(ism, &cmd);
331 }
332
333 static int ism_set_vlan_required(struct smcd_dev *smcd)
334 {
335         return ism_cmd_simple(smcd->priv, ISM_SET_VLAN);
336 }
337
338 static int ism_reset_vlan_required(struct smcd_dev *smcd)
339 {
340         return ism_cmd_simple(smcd->priv, ISM_RESET_VLAN);
341 }
342
343 static int ism_signal_ieq(struct smcd_dev *smcd, u64 rgid, u32 trigger_irq,
344                           u32 event_code, u64 info)
345 {
346         struct ism_dev *ism = smcd->priv;
347         union ism_sig_ieq cmd;
348
349         memset(&cmd, 0, sizeof(cmd));
350         cmd.request.hdr.cmd = ISM_SIGNAL_IEQ;
351         cmd.request.hdr.len = sizeof(cmd.request);
352
353         cmd.request.rgid = rgid;
354         cmd.request.trigger_irq = trigger_irq;
355         cmd.request.event_code = event_code;
356         cmd.request.info = info;
357
358         return ism_cmd(ism, &cmd);
359 }
360
361 static unsigned int max_bytes(unsigned int start, unsigned int len,
362                               unsigned int boundary)
363 {
364         return min(boundary - (start & (boundary - 1)), len);
365 }
366
367 static int ism_move(struct smcd_dev *smcd, u64 dmb_tok, unsigned int idx,
368                     bool sf, unsigned int offset, void *data, unsigned int size)
369 {
370         struct ism_dev *ism = smcd->priv;
371         unsigned int bytes;
372         u64 dmb_req;
373         int ret;
374
375         while (size) {
376                 bytes = max_bytes(offset, size, PAGE_SIZE);
377                 dmb_req = ISM_CREATE_REQ(dmb_tok, idx, size == bytes ? sf : 0,
378                                          offset);
379
380                 ret = __ism_move(ism, dmb_req, data, bytes);
381                 if (ret)
382                         return ret;
383
384                 size -= bytes;
385                 data += bytes;
386                 offset += bytes;
387         }
388
389         return 0;
390 }
391
392 static void ism_handle_event(struct ism_dev *ism)
393 {
394         struct smcd_event *entry;
395
396         while ((ism->ieq_idx + 1) != READ_ONCE(ism->ieq->header.idx)) {
397                 if (++(ism->ieq_idx) == ARRAY_SIZE(ism->ieq->entry))
398                         ism->ieq_idx = 0;
399
400                 entry = &ism->ieq->entry[ism->ieq_idx];
401                 debug_event(ism_debug_info, 2, entry, sizeof(*entry));
402                 smcd_handle_event(ism->smcd, entry);
403         }
404 }
405
406 static irqreturn_t ism_handle_irq(int irq, void *data)
407 {
408         struct ism_dev *ism = data;
409         unsigned long bit, end;
410         unsigned long *bv;
411
412         bv = (void *) &ism->sba->dmb_bits[ISM_DMB_WORD_OFFSET];
413         end = sizeof(ism->sba->dmb_bits) * BITS_PER_BYTE - ISM_DMB_BIT_OFFSET;
414
415         spin_lock(&ism->lock);
416         ism->sba->s = 0;
417         barrier();
418         for (bit = 0;;) {
419                 bit = find_next_bit_inv(bv, end, bit);
420                 if (bit >= end)
421                         break;
422
423                 clear_bit_inv(bit, bv);
424                 ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET] = 0;
425                 barrier();
426                 smcd_handle_irq(ism->smcd, bit + ISM_DMB_BIT_OFFSET);
427         }
428
429         if (ism->sba->e) {
430                 ism->sba->e = 0;
431                 barrier();
432                 ism_handle_event(ism);
433         }
434         spin_unlock(&ism->lock);
435         return IRQ_HANDLED;
436 }
437
438 static const struct smcd_ops ism_ops = {
439         .query_remote_gid = ism_query_rgid,
440         .register_dmb = ism_register_dmb,
441         .unregister_dmb = ism_unregister_dmb,
442         .add_vlan_id = ism_add_vlan_id,
443         .del_vlan_id = ism_del_vlan_id,
444         .set_vlan_required = ism_set_vlan_required,
445         .reset_vlan_required = ism_reset_vlan_required,
446         .signal_event = ism_signal_ieq,
447         .move_data = ism_move,
448 };
449
450 static int ism_dev_init(struct ism_dev *ism)
451 {
452         struct pci_dev *pdev = ism->pdev;
453         int ret;
454
455         ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
456         if (ret <= 0)
457                 goto out;
458
459         ret = request_irq(pci_irq_vector(pdev, 0), ism_handle_irq, 0,
460                           pci_name(pdev), ism);
461         if (ret)
462                 goto free_vectors;
463
464         ret = register_sba(ism);
465         if (ret)
466                 goto free_irq;
467
468         ret = register_ieq(ism);
469         if (ret)
470                 goto unreg_sba;
471
472         ret = ism_read_local_gid(ism);
473         if (ret)
474                 goto unreg_ieq;
475
476         ret = smcd_register_dev(ism->smcd);
477         if (ret)
478                 goto unreg_ieq;
479
480         query_info(ism);
481         return 0;
482
483 unreg_ieq:
484         unregister_ieq(ism);
485 unreg_sba:
486         unregister_sba(ism);
487 free_irq:
488         free_irq(pci_irq_vector(pdev, 0), ism);
489 free_vectors:
490         pci_free_irq_vectors(pdev);
491 out:
492         return ret;
493 }
494
495 static int ism_probe(struct pci_dev *pdev, const struct pci_device_id *id)
496 {
497         struct ism_dev *ism;
498         int ret;
499
500         ism = kzalloc(sizeof(*ism), GFP_KERNEL);
501         if (!ism)
502                 return -ENOMEM;
503
504         spin_lock_init(&ism->lock);
505         dev_set_drvdata(&pdev->dev, ism);
506         ism->pdev = pdev;
507
508         ret = pci_enable_device_mem(pdev);
509         if (ret)
510                 goto err;
511
512         ret = pci_request_mem_regions(pdev, DRV_NAME);
513         if (ret)
514                 goto err_disable;
515
516         ism->ctl = pci_iomap(pdev, 2, 0);
517         if (!ism->ctl)
518                 goto err_resource;
519
520         ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
521         if (ret)
522                 goto err_unmap;
523
524         pci_set_dma_seg_boundary(pdev, SZ_1M - 1);
525         pci_set_dma_max_seg_size(pdev, SZ_1M);
526         pci_set_master(pdev);
527
528         ism->smcd = smcd_alloc_dev(&pdev->dev, dev_name(&pdev->dev), &ism_ops,
529                                    ISM_NR_DMBS);
530         if (!ism->smcd)
531                 goto err_unmap;
532
533         ism->smcd->priv = ism;
534         ret = ism_dev_init(ism);
535         if (ret)
536                 goto err_free;
537
538         return 0;
539
540 err_free:
541         smcd_free_dev(ism->smcd);
542 err_unmap:
543         pci_iounmap(pdev, ism->ctl);
544 err_resource:
545         pci_release_mem_regions(pdev);
546 err_disable:
547         pci_disable_device(pdev);
548 err:
549         kfree(ism);
550         dev_set_drvdata(&pdev->dev, NULL);
551         return ret;
552 }
553
554 static void ism_dev_exit(struct ism_dev *ism)
555 {
556         struct pci_dev *pdev = ism->pdev;
557
558         smcd_unregister_dev(ism->smcd);
559         unregister_ieq(ism);
560         unregister_sba(ism);
561         free_irq(pci_irq_vector(pdev, 0), ism);
562         pci_free_irq_vectors(pdev);
563 }
564
565 static void ism_remove(struct pci_dev *pdev)
566 {
567         struct ism_dev *ism = dev_get_drvdata(&pdev->dev);
568
569         ism_dev_exit(ism);
570
571         smcd_free_dev(ism->smcd);
572         pci_iounmap(pdev, ism->ctl);
573         pci_release_mem_regions(pdev);
574         pci_disable_device(pdev);
575         dev_set_drvdata(&pdev->dev, NULL);
576         kfree(ism);
577 }
578
579 static int ism_suspend(struct device *dev)
580 {
581         struct ism_dev *ism = dev_get_drvdata(dev);
582
583         ism_dev_exit(ism);
584         return 0;
585 }
586
587 static int ism_resume(struct device *dev)
588 {
589         struct ism_dev *ism = dev_get_drvdata(dev);
590
591         return ism_dev_init(ism);
592 }
593
594 static SIMPLE_DEV_PM_OPS(ism_pm_ops, ism_suspend, ism_resume);
595
596 static struct pci_driver ism_driver = {
597         .name     = DRV_NAME,
598         .id_table = ism_device_table,
599         .probe    = ism_probe,
600         .remove   = ism_remove,
601         .driver   = {
602                 .pm = &ism_pm_ops,
603         },
604 };
605
606 static int __init ism_init(void)
607 {
608         int ret;
609
610         ism_debug_info = debug_register("ism", 2, 1, 16);
611         if (!ism_debug_info)
612                 return -ENODEV;
613
614         debug_register_view(ism_debug_info, &debug_hex_ascii_view);
615         ret = pci_register_driver(&ism_driver);
616         if (ret)
617                 debug_unregister(ism_debug_info);
618
619         return ret;
620 }
621
622 static void __exit ism_exit(void)
623 {
624         pci_unregister_driver(&ism_driver);
625         debug_unregister(ism_debug_info);
626 }
627
628 module_init(ism_init);
629 module_exit(ism_exit);