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Note: File does not exist in v3.1.
  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
 24MODULE_DESCRIPTION("ISM driver for s390");
 25MODULE_LICENSE("GPL");
 26
 27#define PCI_DEVICE_ID_IBM_ISM 0x04ED
 28#define DRV_NAME "ism"
 29
 30static const struct pci_device_id ism_device_table[] = {
 31	{ PCI_VDEVICE(IBM, PCI_DEVICE_ID_IBM_ISM), 0 },
 32	{ 0, }
 33};
 34MODULE_DEVICE_TABLE(pci, ism_device_table);
 35
 36static debug_info_t *ism_debug_info;
 37
 38static 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));
 55out:
 56	return resp->ret;
 57}
 58
 59static 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
 70static 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));
 83out:
 84	return 0;
 85}
 86
 87static 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
114static 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
143static 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
163static 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
183static 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;
197out:
198	return ret;
199}
200
201static 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
218static 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
225static 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 |
247					   __GFP_NOMEMALLOC | __GFP_NORETRY);
248	if (!dmb->cpu_addr)
249		clear_bit(dmb->sba_idx, ism->sba_bitmap);
250
251	return dmb->cpu_addr ? 0 : -ENOMEM;
252}
253
254static int ism_register_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
255{
256	struct ism_dev *ism = smcd->priv;
257	union ism_reg_dmb cmd;
258	int ret;
259
260	ret = ism_alloc_dmb(ism, dmb);
261	if (ret)
262		goto out;
263
264	memset(&cmd, 0, sizeof(cmd));
265	cmd.request.hdr.cmd = ISM_REG_DMB;
266	cmd.request.hdr.len = sizeof(cmd.request);
267
268	cmd.request.dmb = dmb->dma_addr;
269	cmd.request.dmb_len = dmb->dmb_len;
270	cmd.request.sba_idx = dmb->sba_idx;
271	cmd.request.vlan_valid = dmb->vlan_valid;
272	cmd.request.vlan_id = dmb->vlan_id;
273	cmd.request.rgid = dmb->rgid;
274
275	ret = ism_cmd(ism, &cmd);
276	if (ret) {
277		ism_free_dmb(ism, dmb);
278		goto out;
279	}
280	dmb->dmb_tok = cmd.response.dmb_tok;
281out:
282	return ret;
283}
284
285static int ism_unregister_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
286{
287	struct ism_dev *ism = smcd->priv;
288	union ism_unreg_dmb cmd;
289	int ret;
290
291	memset(&cmd, 0, sizeof(cmd));
292	cmd.request.hdr.cmd = ISM_UNREG_DMB;
293	cmd.request.hdr.len = sizeof(cmd.request);
294
295	cmd.request.dmb_tok = dmb->dmb_tok;
296
297	ret = ism_cmd(ism, &cmd);
298	if (ret && ret != ISM_ERROR)
299		goto out;
300
301	ism_free_dmb(ism, dmb);
302out:
303	return ret;
304}
305
306static int ism_add_vlan_id(struct smcd_dev *smcd, u64 vlan_id)
307{
308	struct ism_dev *ism = smcd->priv;
309	union ism_set_vlan_id cmd;
310
311	memset(&cmd, 0, sizeof(cmd));
312	cmd.request.hdr.cmd = ISM_ADD_VLAN_ID;
313	cmd.request.hdr.len = sizeof(cmd.request);
314
315	cmd.request.vlan_id = vlan_id;
316
317	return ism_cmd(ism, &cmd);
318}
319
320static int ism_del_vlan_id(struct smcd_dev *smcd, u64 vlan_id)
321{
322	struct ism_dev *ism = smcd->priv;
323	union ism_set_vlan_id cmd;
324
325	memset(&cmd, 0, sizeof(cmd));
326	cmd.request.hdr.cmd = ISM_DEL_VLAN_ID;
327	cmd.request.hdr.len = sizeof(cmd.request);
328
329	cmd.request.vlan_id = vlan_id;
330
331	return ism_cmd(ism, &cmd);
332}
333
334static int ism_set_vlan_required(struct smcd_dev *smcd)
335{
336	return ism_cmd_simple(smcd->priv, ISM_SET_VLAN);
337}
338
339static int ism_reset_vlan_required(struct smcd_dev *smcd)
340{
341	return ism_cmd_simple(smcd->priv, ISM_RESET_VLAN);
342}
343
344static int ism_signal_ieq(struct smcd_dev *smcd, u64 rgid, u32 trigger_irq,
345			  u32 event_code, u64 info)
346{
347	struct ism_dev *ism = smcd->priv;
348	union ism_sig_ieq cmd;
349
350	memset(&cmd, 0, sizeof(cmd));
351	cmd.request.hdr.cmd = ISM_SIGNAL_IEQ;
352	cmd.request.hdr.len = sizeof(cmd.request);
353
354	cmd.request.rgid = rgid;
355	cmd.request.trigger_irq = trigger_irq;
356	cmd.request.event_code = event_code;
357	cmd.request.info = info;
358
359	return ism_cmd(ism, &cmd);
360}
361
362static unsigned int max_bytes(unsigned int start, unsigned int len,
363			      unsigned int boundary)
364{
365	return min(boundary - (start & (boundary - 1)), len);
366}
367
368static int ism_move(struct smcd_dev *smcd, u64 dmb_tok, unsigned int idx,
369		    bool sf, unsigned int offset, void *data, unsigned int size)
370{
371	struct ism_dev *ism = smcd->priv;
372	unsigned int bytes;
373	u64 dmb_req;
374	int ret;
375
376	while (size) {
377		bytes = max_bytes(offset, size, PAGE_SIZE);
378		dmb_req = ISM_CREATE_REQ(dmb_tok, idx, size == bytes ? sf : 0,
379					 offset);
380
381		ret = __ism_move(ism, dmb_req, data, bytes);
382		if (ret)
383			return ret;
384
385		size -= bytes;
386		data += bytes;
387		offset += bytes;
388	}
389
390	return 0;
391}
392
393static struct ism_systemeid SYSTEM_EID = {
394	.seid_string = "IBM-SYSZ-ISMSEID00000000",
395	.serial_number = "0000",
396	.type = "0000",
397};
398
399static void ism_create_system_eid(void)
400{
401	struct cpuid id;
402	u16 ident_tail;
403	char tmp[5];
404
405	get_cpu_id(&id);
406	ident_tail = (u16)(id.ident & ISM_IDENT_MASK);
407	snprintf(tmp, 5, "%04X", ident_tail);
408	memcpy(&SYSTEM_EID.serial_number, tmp, 4);
409	snprintf(tmp, 5, "%04X", id.machine);
410	memcpy(&SYSTEM_EID.type, tmp, 4);
411}
412
413static u8 *ism_get_system_eid(void)
414{
415	return SYSTEM_EID.seid_string;
416}
417
418static u16 ism_get_chid(struct smcd_dev *smcd)
419{
420	struct ism_dev *ism = (struct ism_dev *)smcd->priv;
421
422	if (!ism || !ism->pdev)
423		return 0;
424
425	return to_zpci(ism->pdev)->pchid;
426}
427
428static 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
442static 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	u16 dmbemask;
448
449	bv = (void *) &ism->sba->dmb_bits[ISM_DMB_WORD_OFFSET];
450	end = sizeof(ism->sba->dmb_bits) * BITS_PER_BYTE - ISM_DMB_BIT_OFFSET;
451
452	spin_lock(&ism->lock);
453	ism->sba->s = 0;
454	barrier();
455	for (bit = 0;;) {
456		bit = find_next_bit_inv(bv, end, bit);
457		if (bit >= end)
458			break;
459
460		clear_bit_inv(bit, bv);
461		dmbemask = ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET];
462		ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET] = 0;
463		barrier();
464		smcd_handle_irq(ism->smcd, bit + ISM_DMB_BIT_OFFSET, dmbemask);
465	}
466
467	if (ism->sba->e) {
468		ism->sba->e = 0;
469		barrier();
470		ism_handle_event(ism);
471	}
472	spin_unlock(&ism->lock);
473	return IRQ_HANDLED;
474}
475
476static const struct smcd_ops ism_ops = {
477	.query_remote_gid = ism_query_rgid,
478	.register_dmb = ism_register_dmb,
479	.unregister_dmb = ism_unregister_dmb,
480	.add_vlan_id = ism_add_vlan_id,
481	.del_vlan_id = ism_del_vlan_id,
482	.set_vlan_required = ism_set_vlan_required,
483	.reset_vlan_required = ism_reset_vlan_required,
484	.signal_event = ism_signal_ieq,
485	.move_data = ism_move,
486	.get_system_eid = ism_get_system_eid,
487	.get_chid = ism_get_chid,
488};
489
490static int ism_dev_init(struct ism_dev *ism)
491{
492	struct pci_dev *pdev = ism->pdev;
493	int ret;
494
495	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
496	if (ret <= 0)
497		goto out;
498
499	ret = request_irq(pci_irq_vector(pdev, 0), ism_handle_irq, 0,
500			  pci_name(pdev), ism);
501	if (ret)
502		goto free_vectors;
503
504	ret = register_sba(ism);
505	if (ret)
506		goto free_irq;
507
508	ret = register_ieq(ism);
509	if (ret)
510		goto unreg_sba;
511
512	ret = ism_read_local_gid(ism);
513	if (ret)
514		goto unreg_ieq;
515
516	if (!ism_add_vlan_id(ism->smcd, ISM_RESERVED_VLANID))
517		/* hardware is V2 capable */
518		ism_create_system_eid();
519
520	ret = smcd_register_dev(ism->smcd);
521	if (ret)
522		goto unreg_ieq;
523
524	query_info(ism);
525	return 0;
526
527unreg_ieq:
528	unregister_ieq(ism);
529unreg_sba:
530	unregister_sba(ism);
531free_irq:
532	free_irq(pci_irq_vector(pdev, 0), ism);
533free_vectors:
534	pci_free_irq_vectors(pdev);
535out:
536	return ret;
537}
538
539static int ism_probe(struct pci_dev *pdev, const struct pci_device_id *id)
540{
541	struct ism_dev *ism;
542	int ret;
543
544	ism = kzalloc(sizeof(*ism), GFP_KERNEL);
545	if (!ism)
546		return -ENOMEM;
547
548	spin_lock_init(&ism->lock);
549	dev_set_drvdata(&pdev->dev, ism);
550	ism->pdev = pdev;
551
552	ret = pci_enable_device_mem(pdev);
553	if (ret)
554		goto err;
555
556	ret = pci_request_mem_regions(pdev, DRV_NAME);
557	if (ret)
558		goto err_disable;
559
560	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
561	if (ret)
562		goto err_resource;
563
564	dma_set_seg_boundary(&pdev->dev, SZ_1M - 1);
565	dma_set_max_seg_size(&pdev->dev, SZ_1M);
566	pci_set_master(pdev);
567
568	ism->smcd = smcd_alloc_dev(&pdev->dev, dev_name(&pdev->dev), &ism_ops,
569				   ISM_NR_DMBS);
570	if (!ism->smcd) {
571		ret = -ENOMEM;
572		goto err_resource;
573	}
574
575	ism->smcd->priv = ism;
576	ret = ism_dev_init(ism);
577	if (ret)
578		goto err_free;
579
580	return 0;
581
582err_free:
583	smcd_free_dev(ism->smcd);
584err_resource:
585	pci_release_mem_regions(pdev);
586err_disable:
587	pci_disable_device(pdev);
588err:
589	kfree(ism);
590	dev_set_drvdata(&pdev->dev, NULL);
591	return ret;
592}
593
594static void ism_dev_exit(struct ism_dev *ism)
595{
596	struct pci_dev *pdev = ism->pdev;
597
598	smcd_unregister_dev(ism->smcd);
599	if (SYSTEM_EID.serial_number[0] != '0' ||
600	    SYSTEM_EID.type[0] != '0')
601		ism_del_vlan_id(ism->smcd, ISM_RESERVED_VLANID);
602	unregister_ieq(ism);
603	unregister_sba(ism);
604	free_irq(pci_irq_vector(pdev, 0), ism);
605	pci_free_irq_vectors(pdev);
606}
607
608static void ism_remove(struct pci_dev *pdev)
609{
610	struct ism_dev *ism = dev_get_drvdata(&pdev->dev);
611
612	ism_dev_exit(ism);
613
614	smcd_free_dev(ism->smcd);
615	pci_release_mem_regions(pdev);
616	pci_disable_device(pdev);
617	dev_set_drvdata(&pdev->dev, NULL);
618	kfree(ism);
619}
620
621static struct pci_driver ism_driver = {
622	.name	  = DRV_NAME,
623	.id_table = ism_device_table,
624	.probe	  = ism_probe,
625	.remove	  = ism_remove,
626};
627
628static int __init ism_init(void)
629{
630	int ret;
631
632	ism_debug_info = debug_register("ism", 2, 1, 16);
633	if (!ism_debug_info)
634		return -ENODEV;
635
636	debug_register_view(ism_debug_info, &debug_hex_ascii_view);
637	ret = pci_register_driver(&ism_driver);
638	if (ret)
639		debug_unregister(ism_debug_info);
640
641	return ret;
642}
643
644static void __exit ism_exit(void)
645{
646	pci_unregister_driver(&ism_driver);
647	debug_unregister(ism_debug_info);
648}
649
650module_init(ism_init);
651module_exit(ism_exit);