xref: /openbmc/linux/arch/s390/pci/pci_clp.c (revision 0e96cf7f)
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 	zdev->mio_capable = response->mio_addr_avail;
167 	for (i = 0; i < PCI_BAR_COUNT; i++) {
168 		if (!(response->mio.valid & (1 << (PCI_BAR_COUNT - i - 1))))
169 			continue;
170 
171 		zdev->bars[i].mio_wb = (void __iomem *) response->mio.addr[i].wb;
172 		zdev->bars[i].mio_wt = (void __iomem *) response->mio.addr[i].wt;
173 	}
174 	return 0;
175 }
176 
177 static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh)
178 {
179 	struct clp_req_rsp_query_pci *rrb;
180 	int rc;
181 
182 	rrb = clp_alloc_block(GFP_KERNEL);
183 	if (!rrb)
184 		return -ENOMEM;
185 
186 	memset(rrb, 0, sizeof(*rrb));
187 	rrb->request.hdr.len = sizeof(rrb->request);
188 	rrb->request.hdr.cmd = CLP_QUERY_PCI_FN;
189 	rrb->response.hdr.len = sizeof(rrb->response);
190 	rrb->request.fh = fh;
191 
192 	rc = clp_req(rrb, CLP_LPS_PCI);
193 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
194 		rc = clp_store_query_pci_fn(zdev, &rrb->response);
195 		if (rc)
196 			goto out;
197 		rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
198 	} else {
199 		zpci_err("Q PCI FN:\n");
200 		zpci_err_clp(rrb->response.hdr.rsp, rc);
201 		rc = -EIO;
202 	}
203 out:
204 	clp_free_block(rrb);
205 	return rc;
206 }
207 
208 int clp_add_pci_device(u32 fid, u32 fh, int configured)
209 {
210 	struct zpci_dev *zdev;
211 	int rc = -ENOMEM;
212 
213 	zpci_dbg(3, "add fid:%x, fh:%x, c:%d\n", fid, fh, configured);
214 	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
215 	if (!zdev)
216 		goto error;
217 
218 	zdev->fh = fh;
219 	zdev->fid = fid;
220 
221 	/* Query function properties and update zdev */
222 	rc = clp_query_pci_fn(zdev, fh);
223 	if (rc)
224 		goto error;
225 
226 	if (configured)
227 		zdev->state = ZPCI_FN_STATE_CONFIGURED;
228 	else
229 		zdev->state = ZPCI_FN_STATE_STANDBY;
230 
231 	rc = zpci_create_device(zdev);
232 	if (rc)
233 		goto error;
234 	return 0;
235 
236 error:
237 	zpci_dbg(0, "add fid:%x, rc:%d\n", fid, rc);
238 	kfree(zdev);
239 	return rc;
240 }
241 
242 /*
243  * Enable/Disable a given PCI function defined by its function handle.
244  */
245 static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)
246 {
247 	struct clp_req_rsp_set_pci *rrb;
248 	int rc, retries = 100;
249 
250 	rrb = clp_alloc_block(GFP_KERNEL);
251 	if (!rrb)
252 		return -ENOMEM;
253 
254 	do {
255 		memset(rrb, 0, sizeof(*rrb));
256 		rrb->request.hdr.len = sizeof(rrb->request);
257 		rrb->request.hdr.cmd = CLP_SET_PCI_FN;
258 		rrb->response.hdr.len = sizeof(rrb->response);
259 		rrb->request.fh = *fh;
260 		rrb->request.oc = command;
261 		rrb->request.ndas = nr_dma_as;
262 
263 		rc = clp_req(rrb, CLP_LPS_PCI);
264 		if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
265 			retries--;
266 			if (retries < 0)
267 				break;
268 			msleep(20);
269 		}
270 	} while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
271 
272 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
273 		*fh = rrb->response.fh;
274 	else {
275 		zpci_err("Set PCI FN:\n");
276 		zpci_err_clp(rrb->response.hdr.rsp, rc);
277 		rc = -EIO;
278 	}
279 	clp_free_block(rrb);
280 	return rc;
281 }
282 
283 int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
284 {
285 	u32 fh = zdev->fh;
286 	int rc;
287 
288 	rc = clp_set_pci_fn(&fh, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
289 	zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, fh, rc);
290 	if (rc)
291 		goto out;
292 
293 	zdev->fh = fh;
294 	if (zdev->mio_capable) {
295 		rc = clp_set_pci_fn(&fh, nr_dma_as, CLP_SET_ENABLE_MIO);
296 		zpci_dbg(3, "ena mio fid:%x, fh:%x, rc:%d\n", zdev->fid, fh, rc);
297 		if (rc)
298 			clp_disable_fh(zdev);
299 	}
300 out:
301 	return rc;
302 }
303 
304 int clp_disable_fh(struct zpci_dev *zdev)
305 {
306 	u32 fh = zdev->fh;
307 	int rc;
308 
309 	if (!zdev_enabled(zdev))
310 		return 0;
311 
312 	rc = clp_set_pci_fn(&fh, 0, CLP_SET_DISABLE_PCI_FN);
313 	zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, fh, rc);
314 	if (!rc)
315 		zdev->fh = fh;
316 
317 	return rc;
318 }
319 
320 static int clp_list_pci(struct clp_req_rsp_list_pci *rrb, void *data,
321 			void (*cb)(struct clp_fh_list_entry *, void *))
322 {
323 	u64 resume_token = 0;
324 	int entries, i, rc;
325 
326 	do {
327 		memset(rrb, 0, sizeof(*rrb));
328 		rrb->request.hdr.len = sizeof(rrb->request);
329 		rrb->request.hdr.cmd = CLP_LIST_PCI;
330 		/* store as many entries as possible */
331 		rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
332 		rrb->request.resume_token = resume_token;
333 
334 		/* Get PCI function handle list */
335 		rc = clp_req(rrb, CLP_LPS_PCI);
336 		if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
337 			zpci_err("List PCI FN:\n");
338 			zpci_err_clp(rrb->response.hdr.rsp, rc);
339 			rc = -EIO;
340 			goto out;
341 		}
342 
343 		update_uid_checking(rrb->response.uid_checking);
344 		WARN_ON_ONCE(rrb->response.entry_size !=
345 			sizeof(struct clp_fh_list_entry));
346 
347 		entries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
348 			rrb->response.entry_size;
349 
350 		resume_token = rrb->response.resume_token;
351 		for (i = 0; i < entries; i++)
352 			cb(&rrb->response.fh_list[i], data);
353 	} while (resume_token);
354 out:
355 	return rc;
356 }
357 
358 static void __clp_add(struct clp_fh_list_entry *entry, void *data)
359 {
360 	struct zpci_dev *zdev;
361 
362 	if (!entry->vendor_id)
363 		return;
364 
365 	zdev = get_zdev_by_fid(entry->fid);
366 	if (!zdev)
367 		clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
368 }
369 
370 static void __clp_update(struct clp_fh_list_entry *entry, void *data)
371 {
372 	struct zpci_dev *zdev;
373 
374 	if (!entry->vendor_id)
375 		return;
376 
377 	zdev = get_zdev_by_fid(entry->fid);
378 	if (!zdev)
379 		return;
380 
381 	zdev->fh = entry->fh;
382 }
383 
384 int clp_scan_pci_devices(void)
385 {
386 	struct clp_req_rsp_list_pci *rrb;
387 	int rc;
388 
389 	rrb = clp_alloc_block(GFP_KERNEL);
390 	if (!rrb)
391 		return -ENOMEM;
392 
393 	rc = clp_list_pci(rrb, NULL, __clp_add);
394 
395 	clp_free_block(rrb);
396 	return rc;
397 }
398 
399 int clp_rescan_pci_devices(void)
400 {
401 	struct clp_req_rsp_list_pci *rrb;
402 	int rc;
403 
404 	zpci_remove_reserved_devices();
405 
406 	rrb = clp_alloc_block(GFP_KERNEL);
407 	if (!rrb)
408 		return -ENOMEM;
409 
410 	rc = clp_list_pci(rrb, NULL, __clp_add);
411 
412 	clp_free_block(rrb);
413 	return rc;
414 }
415 
416 int clp_rescan_pci_devices_simple(void)
417 {
418 	struct clp_req_rsp_list_pci *rrb;
419 	int rc;
420 
421 	rrb = clp_alloc_block(GFP_NOWAIT);
422 	if (!rrb)
423 		return -ENOMEM;
424 
425 	rc = clp_list_pci(rrb, NULL, __clp_update);
426 
427 	clp_free_block(rrb);
428 	return rc;
429 }
430 
431 struct clp_state_data {
432 	u32 fid;
433 	enum zpci_state state;
434 };
435 
436 static void __clp_get_state(struct clp_fh_list_entry *entry, void *data)
437 {
438 	struct clp_state_data *sd = data;
439 
440 	if (entry->fid != sd->fid)
441 		return;
442 
443 	sd->state = entry->config_state;
444 }
445 
446 int clp_get_state(u32 fid, enum zpci_state *state)
447 {
448 	struct clp_req_rsp_list_pci *rrb;
449 	struct clp_state_data sd = {fid, ZPCI_FN_STATE_RESERVED};
450 	int rc;
451 
452 	rrb = clp_alloc_block(GFP_ATOMIC);
453 	if (!rrb)
454 		return -ENOMEM;
455 
456 	rc = clp_list_pci(rrb, &sd, __clp_get_state);
457 	if (!rc)
458 		*state = sd.state;
459 
460 	clp_free_block(rrb);
461 	return rc;
462 }
463 
464 static int clp_base_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
465 {
466 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
467 
468 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
469 	    lpcb->response.hdr.len > limit)
470 		return -EINVAL;
471 	return clp_req(lpcb, CLP_LPS_BASE) ? -EOPNOTSUPP : 0;
472 }
473 
474 static int clp_base_command(struct clp_req *req, struct clp_req_hdr *lpcb)
475 {
476 	switch (lpcb->cmd) {
477 	case 0x0001: /* store logical-processor characteristics */
478 		return clp_base_slpc(req, (void *) lpcb);
479 	default:
480 		return -EINVAL;
481 	}
482 }
483 
484 static int clp_pci_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
485 {
486 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
487 
488 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
489 	    lpcb->response.hdr.len > limit)
490 		return -EINVAL;
491 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
492 }
493 
494 static int clp_pci_list(struct clp_req *req, struct clp_req_rsp_list_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)
502 		return -EINVAL;
503 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
504 }
505 
506 static int clp_pci_query(struct clp_req *req,
507 			 struct clp_req_rsp_query_pci *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 		return -EINVAL;
516 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
517 }
518 
519 static int clp_pci_query_grp(struct clp_req *req,
520 			     struct clp_req_rsp_query_pci_grp *lpcb)
521 {
522 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
523 
524 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
525 	    lpcb->response.hdr.len > limit)
526 		return -EINVAL;
527 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0 ||
528 	    lpcb->request.reserved4 != 0)
529 		return -EINVAL;
530 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
531 }
532 
533 static int clp_pci_command(struct clp_req *req, struct clp_req_hdr *lpcb)
534 {
535 	switch (lpcb->cmd) {
536 	case 0x0001: /* store logical-processor characteristics */
537 		return clp_pci_slpc(req, (void *) lpcb);
538 	case 0x0002: /* list PCI functions */
539 		return clp_pci_list(req, (void *) lpcb);
540 	case 0x0003: /* query PCI function */
541 		return clp_pci_query(req, (void *) lpcb);
542 	case 0x0004: /* query PCI function group */
543 		return clp_pci_query_grp(req, (void *) lpcb);
544 	default:
545 		return -EINVAL;
546 	}
547 }
548 
549 static int clp_normal_command(struct clp_req *req)
550 {
551 	struct clp_req_hdr *lpcb;
552 	void __user *uptr;
553 	int rc;
554 
555 	rc = -EINVAL;
556 	if (req->lps != 0 && req->lps != 2)
557 		goto out;
558 
559 	rc = -ENOMEM;
560 	lpcb = clp_alloc_block(GFP_KERNEL);
561 	if (!lpcb)
562 		goto out;
563 
564 	rc = -EFAULT;
565 	uptr = (void __force __user *)(unsigned long) req->data_p;
566 	if (copy_from_user(lpcb, uptr, PAGE_SIZE) != 0)
567 		goto out_free;
568 
569 	rc = -EINVAL;
570 	if (lpcb->fmt != 0 || lpcb->reserved1 != 0 || lpcb->reserved2 != 0)
571 		goto out_free;
572 
573 	switch (req->lps) {
574 	case 0:
575 		rc = clp_base_command(req, lpcb);
576 		break;
577 	case 2:
578 		rc = clp_pci_command(req, lpcb);
579 		break;
580 	}
581 	if (rc)
582 		goto out_free;
583 
584 	rc = -EFAULT;
585 	if (copy_to_user(uptr, lpcb, PAGE_SIZE) != 0)
586 		goto out_free;
587 
588 	rc = 0;
589 
590 out_free:
591 	clp_free_block(lpcb);
592 out:
593 	return rc;
594 }
595 
596 static int clp_immediate_command(struct clp_req *req)
597 {
598 	void __user *uptr;
599 	unsigned long ilp;
600 	int exists;
601 
602 	if (req->cmd > 1 || clp_get_ilp(&ilp) != 0)
603 		return -EINVAL;
604 
605 	uptr = (void __force __user *)(unsigned long) req->data_p;
606 	if (req->cmd == 0) {
607 		/* Command code 0: test for a specific processor */
608 		exists = test_bit_inv(req->lps, &ilp);
609 		return put_user(exists, (int __user *) uptr);
610 	}
611 	/* Command code 1: return bit mask of installed processors */
612 	return put_user(ilp, (unsigned long __user *) uptr);
613 }
614 
615 static long clp_misc_ioctl(struct file *filp, unsigned int cmd,
616 			   unsigned long arg)
617 {
618 	struct clp_req req;
619 	void __user *argp;
620 
621 	if (cmd != CLP_SYNC)
622 		return -EINVAL;
623 
624 	argp = is_compat_task() ? compat_ptr(arg) : (void __user *) arg;
625 	if (copy_from_user(&req, argp, sizeof(req)))
626 		return -EFAULT;
627 	if (req.r != 0)
628 		return -EINVAL;
629 	return req.c ? clp_immediate_command(&req) : clp_normal_command(&req);
630 }
631 
632 static int clp_misc_release(struct inode *inode, struct file *filp)
633 {
634 	return 0;
635 }
636 
637 static const struct file_operations clp_misc_fops = {
638 	.owner = THIS_MODULE,
639 	.open = nonseekable_open,
640 	.release = clp_misc_release,
641 	.unlocked_ioctl = clp_misc_ioctl,
642 	.compat_ioctl = clp_misc_ioctl,
643 	.llseek = no_llseek,
644 };
645 
646 static struct miscdevice clp_misc_device = {
647 	.minor = MISC_DYNAMIC_MINOR,
648 	.name = "clp",
649 	.fops = &clp_misc_fops,
650 };
651 
652 static int __init clp_misc_init(void)
653 {
654 	return misc_register(&clp_misc_device);
655 }
656 
657 device_initcall(clp_misc_init);
658