xref: /openbmc/linux/arch/s390/pci/pci_clp.c (revision 0c874100)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright IBM Corp. 2012
4  *
5  * Author(s):
6  *   Jan Glauber <jang@linux.vnet.ibm.com>
7  */
8 
9 #define KMSG_COMPONENT "zpci"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11 
12 #include <linux/compat.h>
13 #include <linux/kernel.h>
14 #include <linux/miscdevice.h>
15 #include <linux/slab.h>
16 #include <linux/err.h>
17 #include <linux/delay.h>
18 #include <linux/pci.h>
19 #include <linux/uaccess.h>
20 #include <asm/pci_debug.h>
21 #include <asm/pci_clp.h>
22 #include <asm/clp.h>
23 #include <uapi/asm/clp.h>
24 
25 bool zpci_unique_uid;
26 
27 static void update_uid_checking(bool new)
28 {
29 	if (zpci_unique_uid != new)
30 		zpci_dbg(1, "uid checking:%d\n", new);
31 
32 	zpci_unique_uid = new;
33 }
34 
35 static inline void zpci_err_clp(unsigned int rsp, int rc)
36 {
37 	struct {
38 		unsigned int rsp;
39 		int rc;
40 	} __packed data = {rsp, rc};
41 
42 	zpci_err_hex(&data, sizeof(data));
43 }
44 
45 /*
46  * Call Logical Processor with c=1, lps=0 and command 1
47  * to get the bit mask of installed logical processors
48  */
49 static inline int clp_get_ilp(unsigned long *ilp)
50 {
51 	unsigned long mask;
52 	int cc = 3;
53 
54 	asm volatile (
55 		"	.insn	rrf,0xb9a00000,%[mask],%[cmd],8,0\n"
56 		"0:	ipm	%[cc]\n"
57 		"	srl	%[cc],28\n"
58 		"1:\n"
59 		EX_TABLE(0b, 1b)
60 		: [cc] "+d" (cc), [mask] "=d" (mask) : [cmd] "a" (1)
61 		: "cc");
62 	*ilp = mask;
63 	return cc;
64 }
65 
66 /*
67  * Call Logical Processor with c=0, the give constant lps and an lpcb request.
68  */
69 static inline int clp_req(void *data, unsigned int lps)
70 {
71 	struct { u8 _[CLP_BLK_SIZE]; } *req = data;
72 	u64 ignored;
73 	int cc = 3;
74 
75 	asm volatile (
76 		"	.insn	rrf,0xb9a00000,%[ign],%[req],0,%[lps]\n"
77 		"0:	ipm	%[cc]\n"
78 		"	srl	%[cc],28\n"
79 		"1:\n"
80 		EX_TABLE(0b, 1b)
81 		: [cc] "+d" (cc), [ign] "=d" (ignored), "+m" (*req)
82 		: [req] "a" (req), [lps] "i" (lps)
83 		: "cc");
84 	return cc;
85 }
86 
87 static void *clp_alloc_block(gfp_t gfp_mask)
88 {
89 	return (void *) __get_free_pages(gfp_mask, get_order(CLP_BLK_SIZE));
90 }
91 
92 static void clp_free_block(void *ptr)
93 {
94 	free_pages((unsigned long) ptr, get_order(CLP_BLK_SIZE));
95 }
96 
97 static void clp_store_query_pci_fngrp(struct zpci_dev *zdev,
98 				      struct clp_rsp_query_pci_grp *response)
99 {
100 	zdev->tlb_refresh = response->refresh;
101 	zdev->dma_mask = response->dasm;
102 	zdev->msi_addr = response->msia;
103 	zdev->max_msi = response->noi;
104 	zdev->fmb_update = response->mui;
105 
106 	switch (response->version) {
107 	case 1:
108 		zdev->max_bus_speed = PCIE_SPEED_5_0GT;
109 		break;
110 	default:
111 		zdev->max_bus_speed = PCI_SPEED_UNKNOWN;
112 		break;
113 	}
114 }
115 
116 static int clp_query_pci_fngrp(struct zpci_dev *zdev, u8 pfgid)
117 {
118 	struct clp_req_rsp_query_pci_grp *rrb;
119 	int rc;
120 
121 	rrb = clp_alloc_block(GFP_KERNEL);
122 	if (!rrb)
123 		return -ENOMEM;
124 
125 	memset(rrb, 0, sizeof(*rrb));
126 	rrb->request.hdr.len = sizeof(rrb->request);
127 	rrb->request.hdr.cmd = CLP_QUERY_PCI_FNGRP;
128 	rrb->response.hdr.len = sizeof(rrb->response);
129 	rrb->request.pfgid = pfgid;
130 
131 	rc = clp_req(rrb, CLP_LPS_PCI);
132 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
133 		clp_store_query_pci_fngrp(zdev, &rrb->response);
134 	else {
135 		zpci_err("Q PCI FGRP:\n");
136 		zpci_err_clp(rrb->response.hdr.rsp, rc);
137 		rc = -EIO;
138 	}
139 	clp_free_block(rrb);
140 	return rc;
141 }
142 
143 static int clp_store_query_pci_fn(struct zpci_dev *zdev,
144 				  struct clp_rsp_query_pci *response)
145 {
146 	int i;
147 
148 	for (i = 0; i < PCI_BAR_COUNT; i++) {
149 		zdev->bars[i].val = le32_to_cpu(response->bar[i]);
150 		zdev->bars[i].size = response->bar_size[i];
151 	}
152 	zdev->start_dma = response->sdma;
153 	zdev->end_dma = response->edma;
154 	zdev->pchid = response->pchid;
155 	zdev->pfgid = response->pfgid;
156 	zdev->pft = response->pft;
157 	zdev->vfn = response->vfn;
158 	zdev->uid = response->uid;
159 	zdev->fmb_length = sizeof(u32) * response->fmb_len;
160 
161 	memcpy(zdev->pfip, response->pfip, sizeof(zdev->pfip));
162 	if (response->util_str_avail) {
163 		memcpy(zdev->util_str, response->util_str,
164 		       sizeof(zdev->util_str));
165 	}
166 
167 	return 0;
168 }
169 
170 static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh)
171 {
172 	struct clp_req_rsp_query_pci *rrb;
173 	int rc;
174 
175 	rrb = clp_alloc_block(GFP_KERNEL);
176 	if (!rrb)
177 		return -ENOMEM;
178 
179 	memset(rrb, 0, sizeof(*rrb));
180 	rrb->request.hdr.len = sizeof(rrb->request);
181 	rrb->request.hdr.cmd = CLP_QUERY_PCI_FN;
182 	rrb->response.hdr.len = sizeof(rrb->response);
183 	rrb->request.fh = fh;
184 
185 	rc = clp_req(rrb, CLP_LPS_PCI);
186 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
187 		rc = clp_store_query_pci_fn(zdev, &rrb->response);
188 		if (rc)
189 			goto out;
190 		rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
191 	} else {
192 		zpci_err("Q PCI FN:\n");
193 		zpci_err_clp(rrb->response.hdr.rsp, rc);
194 		rc = -EIO;
195 	}
196 out:
197 	clp_free_block(rrb);
198 	return rc;
199 }
200 
201 int clp_add_pci_device(u32 fid, u32 fh, int configured)
202 {
203 	struct zpci_dev *zdev;
204 	int rc = -ENOMEM;
205 
206 	zpci_dbg(3, "add fid:%x, fh:%x, c:%d\n", fid, fh, configured);
207 	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
208 	if (!zdev)
209 		goto error;
210 
211 	zdev->fh = fh;
212 	zdev->fid = fid;
213 
214 	/* Query function properties and update zdev */
215 	rc = clp_query_pci_fn(zdev, fh);
216 	if (rc)
217 		goto error;
218 
219 	if (configured)
220 		zdev->state = ZPCI_FN_STATE_CONFIGURED;
221 	else
222 		zdev->state = ZPCI_FN_STATE_STANDBY;
223 
224 	rc = zpci_create_device(zdev);
225 	if (rc)
226 		goto error;
227 	return 0;
228 
229 error:
230 	zpci_dbg(0, "add fid:%x, rc:%d\n", fid, rc);
231 	kfree(zdev);
232 	return rc;
233 }
234 
235 /*
236  * Enable/Disable a given PCI function defined by its function handle.
237  */
238 static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)
239 {
240 	struct clp_req_rsp_set_pci *rrb;
241 	int rc, retries = 100;
242 
243 	rrb = clp_alloc_block(GFP_KERNEL);
244 	if (!rrb)
245 		return -ENOMEM;
246 
247 	do {
248 		memset(rrb, 0, sizeof(*rrb));
249 		rrb->request.hdr.len = sizeof(rrb->request);
250 		rrb->request.hdr.cmd = CLP_SET_PCI_FN;
251 		rrb->response.hdr.len = sizeof(rrb->response);
252 		rrb->request.fh = *fh;
253 		rrb->request.oc = command;
254 		rrb->request.ndas = nr_dma_as;
255 
256 		rc = clp_req(rrb, CLP_LPS_PCI);
257 		if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
258 			retries--;
259 			if (retries < 0)
260 				break;
261 			msleep(20);
262 		}
263 	} while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
264 
265 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
266 		*fh = rrb->response.fh;
267 	else {
268 		zpci_err("Set PCI FN:\n");
269 		zpci_err_clp(rrb->response.hdr.rsp, rc);
270 		rc = -EIO;
271 	}
272 	clp_free_block(rrb);
273 	return rc;
274 }
275 
276 int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
277 {
278 	u32 fh = zdev->fh;
279 	int rc;
280 
281 	rc = clp_set_pci_fn(&fh, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
282 	if (!rc)
283 		/* Success -> store enabled handle in zdev */
284 		zdev->fh = fh;
285 
286 	zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
287 	return rc;
288 }
289 
290 int clp_disable_fh(struct zpci_dev *zdev)
291 {
292 	u32 fh = zdev->fh;
293 	int rc;
294 
295 	if (!zdev_enabled(zdev))
296 		return 0;
297 
298 	rc = clp_set_pci_fn(&fh, 0, CLP_SET_DISABLE_PCI_FN);
299 	if (!rc)
300 		/* Success -> store disabled handle in zdev */
301 		zdev->fh = fh;
302 
303 	zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
304 	return rc;
305 }
306 
307 static int clp_list_pci(struct clp_req_rsp_list_pci *rrb, void *data,
308 			void (*cb)(struct clp_fh_list_entry *, void *))
309 {
310 	u64 resume_token = 0;
311 	int entries, i, rc;
312 
313 	do {
314 		memset(rrb, 0, sizeof(*rrb));
315 		rrb->request.hdr.len = sizeof(rrb->request);
316 		rrb->request.hdr.cmd = CLP_LIST_PCI;
317 		/* store as many entries as possible */
318 		rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
319 		rrb->request.resume_token = resume_token;
320 
321 		/* Get PCI function handle list */
322 		rc = clp_req(rrb, CLP_LPS_PCI);
323 		if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
324 			zpci_err("List PCI FN:\n");
325 			zpci_err_clp(rrb->response.hdr.rsp, rc);
326 			rc = -EIO;
327 			goto out;
328 		}
329 
330 		update_uid_checking(rrb->response.uid_checking);
331 		WARN_ON_ONCE(rrb->response.entry_size !=
332 			sizeof(struct clp_fh_list_entry));
333 
334 		entries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
335 			rrb->response.entry_size;
336 
337 		resume_token = rrb->response.resume_token;
338 		for (i = 0; i < entries; i++)
339 			cb(&rrb->response.fh_list[i], data);
340 	} while (resume_token);
341 out:
342 	return rc;
343 }
344 
345 static void __clp_add(struct clp_fh_list_entry *entry, void *data)
346 {
347 	struct zpci_dev *zdev;
348 
349 	if (!entry->vendor_id)
350 		return;
351 
352 	zdev = get_zdev_by_fid(entry->fid);
353 	if (!zdev)
354 		clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
355 }
356 
357 static void __clp_update(struct clp_fh_list_entry *entry, void *data)
358 {
359 	struct zpci_dev *zdev;
360 
361 	if (!entry->vendor_id)
362 		return;
363 
364 	zdev = get_zdev_by_fid(entry->fid);
365 	if (!zdev)
366 		return;
367 
368 	zdev->fh = entry->fh;
369 }
370 
371 int clp_scan_pci_devices(void)
372 {
373 	struct clp_req_rsp_list_pci *rrb;
374 	int rc;
375 
376 	rrb = clp_alloc_block(GFP_KERNEL);
377 	if (!rrb)
378 		return -ENOMEM;
379 
380 	rc = clp_list_pci(rrb, NULL, __clp_add);
381 
382 	clp_free_block(rrb);
383 	return rc;
384 }
385 
386 int clp_rescan_pci_devices(void)
387 {
388 	struct clp_req_rsp_list_pci *rrb;
389 	int rc;
390 
391 	zpci_remove_reserved_devices();
392 
393 	rrb = clp_alloc_block(GFP_KERNEL);
394 	if (!rrb)
395 		return -ENOMEM;
396 
397 	rc = clp_list_pci(rrb, NULL, __clp_add);
398 
399 	clp_free_block(rrb);
400 	return rc;
401 }
402 
403 int clp_rescan_pci_devices_simple(void)
404 {
405 	struct clp_req_rsp_list_pci *rrb;
406 	int rc;
407 
408 	rrb = clp_alloc_block(GFP_NOWAIT);
409 	if (!rrb)
410 		return -ENOMEM;
411 
412 	rc = clp_list_pci(rrb, NULL, __clp_update);
413 
414 	clp_free_block(rrb);
415 	return rc;
416 }
417 
418 struct clp_state_data {
419 	u32 fid;
420 	enum zpci_state state;
421 };
422 
423 static void __clp_get_state(struct clp_fh_list_entry *entry, void *data)
424 {
425 	struct clp_state_data *sd = data;
426 
427 	if (entry->fid != sd->fid)
428 		return;
429 
430 	sd->state = entry->config_state;
431 }
432 
433 int clp_get_state(u32 fid, enum zpci_state *state)
434 {
435 	struct clp_req_rsp_list_pci *rrb;
436 	struct clp_state_data sd = {fid, ZPCI_FN_STATE_RESERVED};
437 	int rc;
438 
439 	rrb = clp_alloc_block(GFP_KERNEL);
440 	if (!rrb)
441 		return -ENOMEM;
442 
443 	rc = clp_list_pci(rrb, &sd, __clp_get_state);
444 	if (!rc)
445 		*state = sd.state;
446 
447 	clp_free_block(rrb);
448 	return rc;
449 }
450 
451 static int clp_base_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
452 {
453 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
454 
455 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
456 	    lpcb->response.hdr.len > limit)
457 		return -EINVAL;
458 	return clp_req(lpcb, CLP_LPS_BASE) ? -EOPNOTSUPP : 0;
459 }
460 
461 static int clp_base_command(struct clp_req *req, struct clp_req_hdr *lpcb)
462 {
463 	switch (lpcb->cmd) {
464 	case 0x0001: /* store logical-processor characteristics */
465 		return clp_base_slpc(req, (void *) lpcb);
466 	default:
467 		return -EINVAL;
468 	}
469 }
470 
471 static int clp_pci_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
472 {
473 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
474 
475 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
476 	    lpcb->response.hdr.len > limit)
477 		return -EINVAL;
478 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
479 }
480 
481 static int clp_pci_list(struct clp_req *req, struct clp_req_rsp_list_pci *lpcb)
482 {
483 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
484 
485 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
486 	    lpcb->response.hdr.len > limit)
487 		return -EINVAL;
488 	if (lpcb->request.reserved2 != 0)
489 		return -EINVAL;
490 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
491 }
492 
493 static int clp_pci_query(struct clp_req *req,
494 			 struct clp_req_rsp_query_pci *lpcb)
495 {
496 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
497 
498 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
499 	    lpcb->response.hdr.len > limit)
500 		return -EINVAL;
501 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0)
502 		return -EINVAL;
503 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
504 }
505 
506 static int clp_pci_query_grp(struct clp_req *req,
507 			     struct clp_req_rsp_query_pci_grp *lpcb)
508 {
509 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
510 
511 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
512 	    lpcb->response.hdr.len > limit)
513 		return -EINVAL;
514 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0 ||
515 	    lpcb->request.reserved4 != 0)
516 		return -EINVAL;
517 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
518 }
519 
520 static int clp_pci_command(struct clp_req *req, struct clp_req_hdr *lpcb)
521 {
522 	switch (lpcb->cmd) {
523 	case 0x0001: /* store logical-processor characteristics */
524 		return clp_pci_slpc(req, (void *) lpcb);
525 	case 0x0002: /* list PCI functions */
526 		return clp_pci_list(req, (void *) lpcb);
527 	case 0x0003: /* query PCI function */
528 		return clp_pci_query(req, (void *) lpcb);
529 	case 0x0004: /* query PCI function group */
530 		return clp_pci_query_grp(req, (void *) lpcb);
531 	default:
532 		return -EINVAL;
533 	}
534 }
535 
536 static int clp_normal_command(struct clp_req *req)
537 {
538 	struct clp_req_hdr *lpcb;
539 	void __user *uptr;
540 	int rc;
541 
542 	rc = -EINVAL;
543 	if (req->lps != 0 && req->lps != 2)
544 		goto out;
545 
546 	rc = -ENOMEM;
547 	lpcb = clp_alloc_block(GFP_KERNEL);
548 	if (!lpcb)
549 		goto out;
550 
551 	rc = -EFAULT;
552 	uptr = (void __force __user *)(unsigned long) req->data_p;
553 	if (copy_from_user(lpcb, uptr, PAGE_SIZE) != 0)
554 		goto out_free;
555 
556 	rc = -EINVAL;
557 	if (lpcb->fmt != 0 || lpcb->reserved1 != 0 || lpcb->reserved2 != 0)
558 		goto out_free;
559 
560 	switch (req->lps) {
561 	case 0:
562 		rc = clp_base_command(req, lpcb);
563 		break;
564 	case 2:
565 		rc = clp_pci_command(req, lpcb);
566 		break;
567 	}
568 	if (rc)
569 		goto out_free;
570 
571 	rc = -EFAULT;
572 	if (copy_to_user(uptr, lpcb, PAGE_SIZE) != 0)
573 		goto out_free;
574 
575 	rc = 0;
576 
577 out_free:
578 	clp_free_block(lpcb);
579 out:
580 	return rc;
581 }
582 
583 static int clp_immediate_command(struct clp_req *req)
584 {
585 	void __user *uptr;
586 	unsigned long ilp;
587 	int exists;
588 
589 	if (req->cmd > 1 || clp_get_ilp(&ilp) != 0)
590 		return -EINVAL;
591 
592 	uptr = (void __force __user *)(unsigned long) req->data_p;
593 	if (req->cmd == 0) {
594 		/* Command code 0: test for a specific processor */
595 		exists = test_bit_inv(req->lps, &ilp);
596 		return put_user(exists, (int __user *) uptr);
597 	}
598 	/* Command code 1: return bit mask of installed processors */
599 	return put_user(ilp, (unsigned long __user *) uptr);
600 }
601 
602 static long clp_misc_ioctl(struct file *filp, unsigned int cmd,
603 			   unsigned long arg)
604 {
605 	struct clp_req req;
606 	void __user *argp;
607 
608 	if (cmd != CLP_SYNC)
609 		return -EINVAL;
610 
611 	argp = is_compat_task() ? compat_ptr(arg) : (void __user *) arg;
612 	if (copy_from_user(&req, argp, sizeof(req)))
613 		return -EFAULT;
614 	if (req.r != 0)
615 		return -EINVAL;
616 	return req.c ? clp_immediate_command(&req) : clp_normal_command(&req);
617 }
618 
619 static int clp_misc_release(struct inode *inode, struct file *filp)
620 {
621 	return 0;
622 }
623 
624 static const struct file_operations clp_misc_fops = {
625 	.owner = THIS_MODULE,
626 	.open = nonseekable_open,
627 	.release = clp_misc_release,
628 	.unlocked_ioctl = clp_misc_ioctl,
629 	.compat_ioctl = clp_misc_ioctl,
630 	.llseek = no_llseek,
631 };
632 
633 static struct miscdevice clp_misc_device = {
634 	.minor = MISC_DYNAMIC_MINOR,
635 	.name = "clp",
636 	.fops = &clp_misc_fops,
637 };
638 
639 static int __init clp_misc_init(void)
640 {
641 	return misc_register(&clp_misc_device);
642 }
643 
644 device_initcall(clp_misc_init);
645