xref: /openbmc/linux/arch/s390/pci/pci_clp.c (revision 78560d41)
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 __always_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_STD_NUM_BARS; 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_STD_NUM_BARS; i++) {
168 		if (!(response->mio.valid & (1 << (PCI_STD_NUM_BARS - 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 and update its function handle if
244  * necessary
245  */
246 static int clp_set_pci_fn(struct zpci_dev *zdev, u8 nr_dma_as, u8 command)
247 {
248 	struct clp_req_rsp_set_pci *rrb;
249 	int rc, retries = 100;
250 	u32 fid = zdev->fid;
251 
252 	rrb = clp_alloc_block(GFP_KERNEL);
253 	if (!rrb)
254 		return -ENOMEM;
255 
256 	do {
257 		memset(rrb, 0, sizeof(*rrb));
258 		rrb->request.hdr.len = sizeof(rrb->request);
259 		rrb->request.hdr.cmd = CLP_SET_PCI_FN;
260 		rrb->response.hdr.len = sizeof(rrb->response);
261 		rrb->request.fh = zdev->fh;
262 		rrb->request.oc = command;
263 		rrb->request.ndas = nr_dma_as;
264 
265 		rc = clp_req(rrb, CLP_LPS_PCI);
266 		if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
267 			retries--;
268 			if (retries < 0)
269 				break;
270 			msleep(20);
271 		}
272 	} while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
273 
274 	if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
275 		zpci_err("Set PCI FN:\n");
276 		zpci_err_clp(rrb->response.hdr.rsp, rc);
277 	}
278 
279 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
280 		zdev->fh = rrb->response.fh;
281 	} else if (!rc && rrb->response.hdr.rsp == CLP_RC_SETPCIFN_ALRDY &&
282 			rrb->response.fh == 0) {
283 		/* Function is already in desired state - update handle */
284 		rc = clp_rescan_pci_devices_simple(&fid);
285 	}
286 	clp_free_block(rrb);
287 	return rc;
288 }
289 
290 int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
291 {
292 	int rc;
293 
294 	rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
295 	zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
296 	if (rc)
297 		goto out;
298 
299 	if (zpci_use_mio(zdev)) {
300 		rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_MIO);
301 		zpci_dbg(3, "ena mio fid:%x, fh:%x, rc:%d\n",
302 				zdev->fid, zdev->fh, rc);
303 		if (rc)
304 			clp_disable_fh(zdev);
305 	}
306 out:
307 	return rc;
308 }
309 
310 int clp_disable_fh(struct zpci_dev *zdev)
311 {
312 	u32 fh = zdev->fh;
313 	int rc;
314 
315 	if (!zdev_enabled(zdev))
316 		return 0;
317 
318 	rc = clp_set_pci_fn(zdev, 0, CLP_SET_DISABLE_PCI_FN);
319 	zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, fh, rc);
320 	return rc;
321 }
322 
323 static int clp_list_pci(struct clp_req_rsp_list_pci *rrb, void *data,
324 			void (*cb)(struct clp_fh_list_entry *, void *))
325 {
326 	u64 resume_token = 0;
327 	int entries, i, rc;
328 
329 	do {
330 		memset(rrb, 0, sizeof(*rrb));
331 		rrb->request.hdr.len = sizeof(rrb->request);
332 		rrb->request.hdr.cmd = CLP_LIST_PCI;
333 		/* store as many entries as possible */
334 		rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
335 		rrb->request.resume_token = resume_token;
336 
337 		/* Get PCI function handle list */
338 		rc = clp_req(rrb, CLP_LPS_PCI);
339 		if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
340 			zpci_err("List PCI FN:\n");
341 			zpci_err_clp(rrb->response.hdr.rsp, rc);
342 			rc = -EIO;
343 			goto out;
344 		}
345 
346 		update_uid_checking(rrb->response.uid_checking);
347 		WARN_ON_ONCE(rrb->response.entry_size !=
348 			sizeof(struct clp_fh_list_entry));
349 
350 		entries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
351 			rrb->response.entry_size;
352 
353 		resume_token = rrb->response.resume_token;
354 		for (i = 0; i < entries; i++)
355 			cb(&rrb->response.fh_list[i], data);
356 	} while (resume_token);
357 out:
358 	return rc;
359 }
360 
361 static void __clp_add(struct clp_fh_list_entry *entry, void *data)
362 {
363 	struct zpci_dev *zdev;
364 
365 	if (!entry->vendor_id)
366 		return;
367 
368 	zdev = get_zdev_by_fid(entry->fid);
369 	if (!zdev)
370 		clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
371 }
372 
373 static void __clp_update(struct clp_fh_list_entry *entry, void *data)
374 {
375 	struct zpci_dev *zdev;
376 	u32 *fid = data;
377 
378 	if (!entry->vendor_id)
379 		return;
380 
381 	if (fid && *fid != entry->fid)
382 		return;
383 
384 	zdev = get_zdev_by_fid(entry->fid);
385 	if (!zdev)
386 		return;
387 
388 	zdev->fh = entry->fh;
389 }
390 
391 int clp_scan_pci_devices(void)
392 {
393 	struct clp_req_rsp_list_pci *rrb;
394 	int rc;
395 
396 	rrb = clp_alloc_block(GFP_KERNEL);
397 	if (!rrb)
398 		return -ENOMEM;
399 
400 	rc = clp_list_pci(rrb, NULL, __clp_add);
401 
402 	clp_free_block(rrb);
403 	return rc;
404 }
405 
406 int clp_rescan_pci_devices(void)
407 {
408 	struct clp_req_rsp_list_pci *rrb;
409 	int rc;
410 
411 	zpci_remove_reserved_devices();
412 
413 	rrb = clp_alloc_block(GFP_KERNEL);
414 	if (!rrb)
415 		return -ENOMEM;
416 
417 	rc = clp_list_pci(rrb, NULL, __clp_add);
418 
419 	clp_free_block(rrb);
420 	return rc;
421 }
422 
423 /* Rescan PCI functions and refresh function handles. If fid is non-NULL only
424  * refresh the handle of the function matching @fid
425  */
426 int clp_rescan_pci_devices_simple(u32 *fid)
427 {
428 	struct clp_req_rsp_list_pci *rrb;
429 	int rc;
430 
431 	rrb = clp_alloc_block(GFP_NOWAIT);
432 	if (!rrb)
433 		return -ENOMEM;
434 
435 	rc = clp_list_pci(rrb, fid, __clp_update);
436 
437 	clp_free_block(rrb);
438 	return rc;
439 }
440 
441 struct clp_state_data {
442 	u32 fid;
443 	enum zpci_state state;
444 };
445 
446 static void __clp_get_state(struct clp_fh_list_entry *entry, void *data)
447 {
448 	struct clp_state_data *sd = data;
449 
450 	if (entry->fid != sd->fid)
451 		return;
452 
453 	sd->state = entry->config_state;
454 }
455 
456 int clp_get_state(u32 fid, enum zpci_state *state)
457 {
458 	struct clp_req_rsp_list_pci *rrb;
459 	struct clp_state_data sd = {fid, ZPCI_FN_STATE_RESERVED};
460 	int rc;
461 
462 	rrb = clp_alloc_block(GFP_ATOMIC);
463 	if (!rrb)
464 		return -ENOMEM;
465 
466 	rc = clp_list_pci(rrb, &sd, __clp_get_state);
467 	if (!rc)
468 		*state = sd.state;
469 
470 	clp_free_block(rrb);
471 	return rc;
472 }
473 
474 static int clp_base_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
475 {
476 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
477 
478 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
479 	    lpcb->response.hdr.len > limit)
480 		return -EINVAL;
481 	return clp_req(lpcb, CLP_LPS_BASE) ? -EOPNOTSUPP : 0;
482 }
483 
484 static int clp_base_command(struct clp_req *req, struct clp_req_hdr *lpcb)
485 {
486 	switch (lpcb->cmd) {
487 	case 0x0001: /* store logical-processor characteristics */
488 		return clp_base_slpc(req, (void *) lpcb);
489 	default:
490 		return -EINVAL;
491 	}
492 }
493 
494 static int clp_pci_slpc(struct clp_req *req, struct clp_req_rsp_slpc *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 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
502 }
503 
504 static int clp_pci_list(struct clp_req *req, struct clp_req_rsp_list_pci *lpcb)
505 {
506 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
507 
508 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
509 	    lpcb->response.hdr.len > limit)
510 		return -EINVAL;
511 	if (lpcb->request.reserved2 != 0)
512 		return -EINVAL;
513 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
514 }
515 
516 static int clp_pci_query(struct clp_req *req,
517 			 struct clp_req_rsp_query_pci *lpcb)
518 {
519 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
520 
521 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
522 	    lpcb->response.hdr.len > limit)
523 		return -EINVAL;
524 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0)
525 		return -EINVAL;
526 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
527 }
528 
529 static int clp_pci_query_grp(struct clp_req *req,
530 			     struct clp_req_rsp_query_pci_grp *lpcb)
531 {
532 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
533 
534 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
535 	    lpcb->response.hdr.len > limit)
536 		return -EINVAL;
537 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0 ||
538 	    lpcb->request.reserved4 != 0)
539 		return -EINVAL;
540 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
541 }
542 
543 static int clp_pci_command(struct clp_req *req, struct clp_req_hdr *lpcb)
544 {
545 	switch (lpcb->cmd) {
546 	case 0x0001: /* store logical-processor characteristics */
547 		return clp_pci_slpc(req, (void *) lpcb);
548 	case 0x0002: /* list PCI functions */
549 		return clp_pci_list(req, (void *) lpcb);
550 	case 0x0003: /* query PCI function */
551 		return clp_pci_query(req, (void *) lpcb);
552 	case 0x0004: /* query PCI function group */
553 		return clp_pci_query_grp(req, (void *) lpcb);
554 	default:
555 		return -EINVAL;
556 	}
557 }
558 
559 static int clp_normal_command(struct clp_req *req)
560 {
561 	struct clp_req_hdr *lpcb;
562 	void __user *uptr;
563 	int rc;
564 
565 	rc = -EINVAL;
566 	if (req->lps != 0 && req->lps != 2)
567 		goto out;
568 
569 	rc = -ENOMEM;
570 	lpcb = clp_alloc_block(GFP_KERNEL);
571 	if (!lpcb)
572 		goto out;
573 
574 	rc = -EFAULT;
575 	uptr = (void __force __user *)(unsigned long) req->data_p;
576 	if (copy_from_user(lpcb, uptr, PAGE_SIZE) != 0)
577 		goto out_free;
578 
579 	rc = -EINVAL;
580 	if (lpcb->fmt != 0 || lpcb->reserved1 != 0 || lpcb->reserved2 != 0)
581 		goto out_free;
582 
583 	switch (req->lps) {
584 	case 0:
585 		rc = clp_base_command(req, lpcb);
586 		break;
587 	case 2:
588 		rc = clp_pci_command(req, lpcb);
589 		break;
590 	}
591 	if (rc)
592 		goto out_free;
593 
594 	rc = -EFAULT;
595 	if (copy_to_user(uptr, lpcb, PAGE_SIZE) != 0)
596 		goto out_free;
597 
598 	rc = 0;
599 
600 out_free:
601 	clp_free_block(lpcb);
602 out:
603 	return rc;
604 }
605 
606 static int clp_immediate_command(struct clp_req *req)
607 {
608 	void __user *uptr;
609 	unsigned long ilp;
610 	int exists;
611 
612 	if (req->cmd > 1 || clp_get_ilp(&ilp) != 0)
613 		return -EINVAL;
614 
615 	uptr = (void __force __user *)(unsigned long) req->data_p;
616 	if (req->cmd == 0) {
617 		/* Command code 0: test for a specific processor */
618 		exists = test_bit_inv(req->lps, &ilp);
619 		return put_user(exists, (int __user *) uptr);
620 	}
621 	/* Command code 1: return bit mask of installed processors */
622 	return put_user(ilp, (unsigned long __user *) uptr);
623 }
624 
625 static long clp_misc_ioctl(struct file *filp, unsigned int cmd,
626 			   unsigned long arg)
627 {
628 	struct clp_req req;
629 	void __user *argp;
630 
631 	if (cmd != CLP_SYNC)
632 		return -EINVAL;
633 
634 	argp = is_compat_task() ? compat_ptr(arg) : (void __user *) arg;
635 	if (copy_from_user(&req, argp, sizeof(req)))
636 		return -EFAULT;
637 	if (req.r != 0)
638 		return -EINVAL;
639 	return req.c ? clp_immediate_command(&req) : clp_normal_command(&req);
640 }
641 
642 static int clp_misc_release(struct inode *inode, struct file *filp)
643 {
644 	return 0;
645 }
646 
647 static const struct file_operations clp_misc_fops = {
648 	.owner = THIS_MODULE,
649 	.open = nonseekable_open,
650 	.release = clp_misc_release,
651 	.unlocked_ioctl = clp_misc_ioctl,
652 	.compat_ioctl = clp_misc_ioctl,
653 	.llseek = no_llseek,
654 };
655 
656 static struct miscdevice clp_misc_device = {
657 	.minor = MISC_DYNAMIC_MINOR,
658 	.name = "clp",
659 	.fops = &clp_misc_fops,
660 };
661 
662 static int __init clp_misc_init(void)
663 {
664 	return misc_register(&clp_misc_device);
665 }
666 
667 device_initcall(clp_misc_init);
668