xref: /openbmc/linux/drivers/s390/net/ism_drv.c (revision 99a15348)
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 <linux/ctype.h>
17 #include <linux/processor.h>
18 #include <net/smc.h>
19 
20 #include <asm/debug.h>
21 
22 #include "ism.h"
23 
24 MODULE_DESCRIPTION("ISM driver for s390");
25 MODULE_LICENSE("GPL");
26 
27 #define PCI_DEVICE_ID_IBM_ISM 0x04ED
28 #define DRV_NAME "ism"
29 
30 static const struct pci_device_id ism_device_table[] = {
31 	{ PCI_VDEVICE(IBM, PCI_DEVICE_ID_IBM_ISM), 0 },
32 	{ 0, }
33 };
34 MODULE_DEVICE_TABLE(pci, ism_device_table);
35 
36 static debug_info_t *ism_debug_info;
37 
38 static int ism_cmd(struct ism_dev *ism, void *cmd)
39 {
40 	struct ism_req_hdr *req = cmd;
41 	struct ism_resp_hdr *resp = cmd;
42 
43 	__ism_write_cmd(ism, req + 1, sizeof(*req), req->len - sizeof(*req));
44 	__ism_write_cmd(ism, req, 0, sizeof(*req));
45 
46 	WRITE_ONCE(resp->ret, ISM_ERROR);
47 
48 	__ism_read_cmd(ism, resp, 0, sizeof(*resp));
49 	if (resp->ret) {
50 		debug_text_event(ism_debug_info, 0, "cmd failure");
51 		debug_event(ism_debug_info, 0, resp, sizeof(*resp));
52 		goto out;
53 	}
54 	__ism_read_cmd(ism, resp + 1, sizeof(*resp), resp->len - sizeof(*resp));
55 out:
56 	return resp->ret;
57 }
58 
59 static int ism_cmd_simple(struct ism_dev *ism, u32 cmd_code)
60 {
61 	union ism_cmd_simple cmd;
62 
63 	memset(&cmd, 0, sizeof(cmd));
64 	cmd.request.hdr.cmd = cmd_code;
65 	cmd.request.hdr.len = sizeof(cmd.request);
66 
67 	return ism_cmd(ism, &cmd);
68 }
69 
70 static int query_info(struct ism_dev *ism)
71 {
72 	union ism_qi cmd;
73 
74 	memset(&cmd, 0, sizeof(cmd));
75 	cmd.request.hdr.cmd = ISM_QUERY_INFO;
76 	cmd.request.hdr.len = sizeof(cmd.request);
77 
78 	if (ism_cmd(ism, &cmd))
79 		goto out;
80 
81 	debug_text_event(ism_debug_info, 3, "query info");
82 	debug_event(ism_debug_info, 3, &cmd.response, sizeof(cmd.response));
83 out:
84 	return 0;
85 }
86 
87 static int register_sba(struct ism_dev *ism)
88 {
89 	union ism_reg_sba cmd;
90 	dma_addr_t dma_handle;
91 	struct ism_sba *sba;
92 
93 	sba = dma_alloc_coherent(&ism->pdev->dev, PAGE_SIZE, &dma_handle,
94 				 GFP_KERNEL);
95 	if (!sba)
96 		return -ENOMEM;
97 
98 	memset(&cmd, 0, sizeof(cmd));
99 	cmd.request.hdr.cmd = ISM_REG_SBA;
100 	cmd.request.hdr.len = sizeof(cmd.request);
101 	cmd.request.sba = dma_handle;
102 
103 	if (ism_cmd(ism, &cmd)) {
104 		dma_free_coherent(&ism->pdev->dev, PAGE_SIZE, sba, dma_handle);
105 		return -EIO;
106 	}
107 
108 	ism->sba = sba;
109 	ism->sba_dma_addr = dma_handle;
110 
111 	return 0;
112 }
113 
114 static int register_ieq(struct ism_dev *ism)
115 {
116 	union ism_reg_ieq cmd;
117 	dma_addr_t dma_handle;
118 	struct ism_eq *ieq;
119 
120 	ieq = dma_alloc_coherent(&ism->pdev->dev, PAGE_SIZE, &dma_handle,
121 				 GFP_KERNEL);
122 	if (!ieq)
123 		return -ENOMEM;
124 
125 	memset(&cmd, 0, sizeof(cmd));
126 	cmd.request.hdr.cmd = ISM_REG_IEQ;
127 	cmd.request.hdr.len = sizeof(cmd.request);
128 	cmd.request.ieq = dma_handle;
129 	cmd.request.len = sizeof(*ieq);
130 
131 	if (ism_cmd(ism, &cmd)) {
132 		dma_free_coherent(&ism->pdev->dev, PAGE_SIZE, ieq, dma_handle);
133 		return -EIO;
134 	}
135 
136 	ism->ieq = ieq;
137 	ism->ieq_idx = -1;
138 	ism->ieq_dma_addr = dma_handle;
139 
140 	return 0;
141 }
142 
143 static int unregister_sba(struct ism_dev *ism)
144 {
145 	int ret;
146 
147 	if (!ism->sba)
148 		return 0;
149 
150 	ret = ism_cmd_simple(ism, ISM_UNREG_SBA);
151 	if (ret && ret != ISM_ERROR)
152 		return -EIO;
153 
154 	dma_free_coherent(&ism->pdev->dev, PAGE_SIZE,
155 			  ism->sba, ism->sba_dma_addr);
156 
157 	ism->sba = NULL;
158 	ism->sba_dma_addr = 0;
159 
160 	return 0;
161 }
162 
163 static int unregister_ieq(struct ism_dev *ism)
164 {
165 	int ret;
166 
167 	if (!ism->ieq)
168 		return 0;
169 
170 	ret = ism_cmd_simple(ism, ISM_UNREG_IEQ);
171 	if (ret && ret != ISM_ERROR)
172 		return -EIO;
173 
174 	dma_free_coherent(&ism->pdev->dev, PAGE_SIZE,
175 			  ism->ieq, ism->ieq_dma_addr);
176 
177 	ism->ieq = NULL;
178 	ism->ieq_dma_addr = 0;
179 
180 	return 0;
181 }
182 
183 static int ism_read_local_gid(struct ism_dev *ism)
184 {
185 	union ism_read_gid cmd;
186 	int ret;
187 
188 	memset(&cmd, 0, sizeof(cmd));
189 	cmd.request.hdr.cmd = ISM_READ_GID;
190 	cmd.request.hdr.len = sizeof(cmd.request);
191 
192 	ret = ism_cmd(ism, &cmd);
193 	if (ret)
194 		goto out;
195 
196 	ism->smcd->local_gid = cmd.response.gid;
197 out:
198 	return ret;
199 }
200 
201 static int ism_query_rgid(struct smcd_dev *smcd, u64 rgid, u32 vid_valid,
202 			  u32 vid)
203 {
204 	struct ism_dev *ism = smcd->priv;
205 	union ism_query_rgid cmd;
206 
207 	memset(&cmd, 0, sizeof(cmd));
208 	cmd.request.hdr.cmd = ISM_QUERY_RGID;
209 	cmd.request.hdr.len = sizeof(cmd.request);
210 
211 	cmd.request.rgid = rgid;
212 	cmd.request.vlan_valid = vid_valid;
213 	cmd.request.vlan_id = vid;
214 
215 	return ism_cmd(ism, &cmd);
216 }
217 
218 static void ism_free_dmb(struct ism_dev *ism, struct smcd_dmb *dmb)
219 {
220 	clear_bit(dmb->sba_idx, ism->sba_bitmap);
221 	dma_free_coherent(&ism->pdev->dev, dmb->dmb_len,
222 			  dmb->cpu_addr, dmb->dma_addr);
223 }
224 
225 static int ism_alloc_dmb(struct ism_dev *ism, struct smcd_dmb *dmb)
226 {
227 	unsigned long bit;
228 
229 	if (PAGE_ALIGN(dmb->dmb_len) > dma_get_max_seg_size(&ism->pdev->dev))
230 		return -EINVAL;
231 
232 	if (!dmb->sba_idx) {
233 		bit = find_next_zero_bit(ism->sba_bitmap, ISM_NR_DMBS,
234 					 ISM_DMB_BIT_OFFSET);
235 		if (bit == ISM_NR_DMBS)
236 			return -ENOSPC;
237 
238 		dmb->sba_idx = bit;
239 	}
240 	if (dmb->sba_idx < ISM_DMB_BIT_OFFSET ||
241 	    test_and_set_bit(dmb->sba_idx, ism->sba_bitmap))
242 		return -EINVAL;
243 
244 	dmb->cpu_addr = dma_alloc_coherent(&ism->pdev->dev, dmb->dmb_len,
245 					   &dmb->dma_addr,
246 					   GFP_KERNEL | __GFP_NOWARN | __GFP_NOMEMALLOC | __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 struct ism_systemeid SYSTEM_EID = {
393 	.seid_string = "IBM-SYSZ-ISMSEID00000000",
394 	.serial_number = "0000",
395 	.type = "0000",
396 };
397 
398 static void ism_create_system_eid(void)
399 {
400 	struct cpuid id;
401 	u16 ident_tail;
402 	char tmp[5];
403 
404 	get_cpu_id(&id);
405 	ident_tail = (u16)(id.ident & ISM_IDENT_MASK);
406 	snprintf(tmp, 5, "%04X", ident_tail);
407 	memcpy(&SYSTEM_EID.serial_number, tmp, 4);
408 	snprintf(tmp, 5, "%04X", id.machine);
409 	memcpy(&SYSTEM_EID.type, tmp, 4);
410 }
411 
412 static void ism_get_system_eid(struct smcd_dev *smcd, u8 **eid)
413 {
414 	*eid = &SYSTEM_EID.seid_string[0];
415 }
416 
417 static u16 ism_get_chid(struct smcd_dev *smcd)
418 {
419 	struct ism_dev *ismdev;
420 
421 	ismdev = (struct ism_dev *)smcd->priv;
422 	if (!ismdev || !ismdev->pdev)
423 		return 0;
424 
425 	return to_zpci(ismdev->pdev)->pchid;
426 }
427 
428 static void ism_handle_event(struct ism_dev *ism)
429 {
430 	struct smcd_event *entry;
431 
432 	while ((ism->ieq_idx + 1) != READ_ONCE(ism->ieq->header.idx)) {
433 		if (++(ism->ieq_idx) == ARRAY_SIZE(ism->ieq->entry))
434 			ism->ieq_idx = 0;
435 
436 		entry = &ism->ieq->entry[ism->ieq_idx];
437 		debug_event(ism_debug_info, 2, entry, sizeof(*entry));
438 		smcd_handle_event(ism->smcd, entry);
439 	}
440 }
441 
442 static irqreturn_t ism_handle_irq(int irq, void *data)
443 {
444 	struct ism_dev *ism = data;
445 	unsigned long bit, end;
446 	unsigned long *bv;
447 
448 	bv = (void *) &ism->sba->dmb_bits[ISM_DMB_WORD_OFFSET];
449 	end = sizeof(ism->sba->dmb_bits) * BITS_PER_BYTE - ISM_DMB_BIT_OFFSET;
450 
451 	spin_lock(&ism->lock);
452 	ism->sba->s = 0;
453 	barrier();
454 	for (bit = 0;;) {
455 		bit = find_next_bit_inv(bv, end, bit);
456 		if (bit >= end)
457 			break;
458 
459 		clear_bit_inv(bit, bv);
460 		ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET] = 0;
461 		barrier();
462 		smcd_handle_irq(ism->smcd, bit + ISM_DMB_BIT_OFFSET);
463 	}
464 
465 	if (ism->sba->e) {
466 		ism->sba->e = 0;
467 		barrier();
468 		ism_handle_event(ism);
469 	}
470 	spin_unlock(&ism->lock);
471 	return IRQ_HANDLED;
472 }
473 
474 static const struct smcd_ops ism_ops = {
475 	.query_remote_gid = ism_query_rgid,
476 	.register_dmb = ism_register_dmb,
477 	.unregister_dmb = ism_unregister_dmb,
478 	.add_vlan_id = ism_add_vlan_id,
479 	.del_vlan_id = ism_del_vlan_id,
480 	.set_vlan_required = ism_set_vlan_required,
481 	.reset_vlan_required = ism_reset_vlan_required,
482 	.signal_event = ism_signal_ieq,
483 	.move_data = ism_move,
484 	.get_system_eid = ism_get_system_eid,
485 	.get_chid = ism_get_chid,
486 };
487 
488 static int ism_dev_init(struct ism_dev *ism)
489 {
490 	struct pci_dev *pdev = ism->pdev;
491 	int ret;
492 
493 	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
494 	if (ret <= 0)
495 		goto out;
496 
497 	ret = request_irq(pci_irq_vector(pdev, 0), ism_handle_irq, 0,
498 			  pci_name(pdev), ism);
499 	if (ret)
500 		goto free_vectors;
501 
502 	ret = register_sba(ism);
503 	if (ret)
504 		goto free_irq;
505 
506 	ret = register_ieq(ism);
507 	if (ret)
508 		goto unreg_sba;
509 
510 	ret = ism_read_local_gid(ism);
511 	if (ret)
512 		goto unreg_ieq;
513 
514 	if (!ism_add_vlan_id(ism->smcd, ISM_RESERVED_VLANID))
515 		/* hardware is V2 capable */
516 		ism_create_system_eid();
517 
518 	ret = smcd_register_dev(ism->smcd);
519 	if (ret)
520 		goto unreg_ieq;
521 
522 	query_info(ism);
523 	return 0;
524 
525 unreg_ieq:
526 	unregister_ieq(ism);
527 unreg_sba:
528 	unregister_sba(ism);
529 free_irq:
530 	free_irq(pci_irq_vector(pdev, 0), ism);
531 free_vectors:
532 	pci_free_irq_vectors(pdev);
533 out:
534 	return ret;
535 }
536 
537 static int ism_probe(struct pci_dev *pdev, const struct pci_device_id *id)
538 {
539 	struct ism_dev *ism;
540 	int ret;
541 
542 	ism = kzalloc(sizeof(*ism), GFP_KERNEL);
543 	if (!ism)
544 		return -ENOMEM;
545 
546 	spin_lock_init(&ism->lock);
547 	dev_set_drvdata(&pdev->dev, ism);
548 	ism->pdev = pdev;
549 
550 	ret = pci_enable_device_mem(pdev);
551 	if (ret)
552 		goto err;
553 
554 	ret = pci_request_mem_regions(pdev, DRV_NAME);
555 	if (ret)
556 		goto err_disable;
557 
558 	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
559 	if (ret)
560 		goto err_resource;
561 
562 	dma_set_seg_boundary(&pdev->dev, SZ_1M - 1);
563 	dma_set_max_seg_size(&pdev->dev, SZ_1M);
564 	pci_set_master(pdev);
565 
566 	ism->smcd = smcd_alloc_dev(&pdev->dev, dev_name(&pdev->dev), &ism_ops,
567 				   ISM_NR_DMBS);
568 	if (!ism->smcd) {
569 		ret = -ENOMEM;
570 		goto err_resource;
571 	}
572 
573 	ism->smcd->priv = ism;
574 	ret = ism_dev_init(ism);
575 	if (ret)
576 		goto err_free;
577 
578 	return 0;
579 
580 err_free:
581 	smcd_free_dev(ism->smcd);
582 err_resource:
583 	pci_release_mem_regions(pdev);
584 err_disable:
585 	pci_disable_device(pdev);
586 err:
587 	kfree(ism);
588 	dev_set_drvdata(&pdev->dev, NULL);
589 	return ret;
590 }
591 
592 static void ism_dev_exit(struct ism_dev *ism)
593 {
594 	struct pci_dev *pdev = ism->pdev;
595 
596 	smcd_unregister_dev(ism->smcd);
597 	if (SYSTEM_EID.serial_number[0] != '0' ||
598 	    SYSTEM_EID.type[0] != '0')
599 		ism_del_vlan_id(ism->smcd, ISM_RESERVED_VLANID);
600 	unregister_ieq(ism);
601 	unregister_sba(ism);
602 	free_irq(pci_irq_vector(pdev, 0), ism);
603 	pci_free_irq_vectors(pdev);
604 }
605 
606 static void ism_remove(struct pci_dev *pdev)
607 {
608 	struct ism_dev *ism = dev_get_drvdata(&pdev->dev);
609 
610 	ism_dev_exit(ism);
611 
612 	smcd_free_dev(ism->smcd);
613 	pci_release_mem_regions(pdev);
614 	pci_disable_device(pdev);
615 	dev_set_drvdata(&pdev->dev, NULL);
616 	kfree(ism);
617 }
618 
619 static struct pci_driver ism_driver = {
620 	.name	  = DRV_NAME,
621 	.id_table = ism_device_table,
622 	.probe	  = ism_probe,
623 	.remove	  = ism_remove,
624 };
625 
626 static int __init ism_init(void)
627 {
628 	int ret;
629 
630 	ism_debug_info = debug_register("ism", 2, 1, 16);
631 	if (!ism_debug_info)
632 		return -ENODEV;
633 
634 	debug_register_view(ism_debug_info, &debug_hex_ascii_view);
635 	ret = pci_register_driver(&ism_driver);
636 	if (ret)
637 		debug_unregister(ism_debug_info);
638 
639 	return ret;
640 }
641 
642 static void __exit ism_exit(void)
643 {
644 	pci_unregister_driver(&ism_driver);
645 	debug_unregister(ism_debug_info);
646 }
647 
648 module_init(ism_init);
649 module_exit(ism_exit);
650