xref: /openbmc/linux/arch/s390/pci/pci_clp.c (revision 4da722ca19f30f7db250db808d1ab1703607a932)
1 /*
2  * Copyright IBM Corp. 2012
3  *
4  * Author(s):
5  *   Jan Glauber <jang@linux.vnet.ibm.com>
6  */
7 
8 #define KMSG_COMPONENT "zpci"
9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10 
11 #include <linux/compat.h>
12 #include <linux/kernel.h>
13 #include <linux/miscdevice.h>
14 #include <linux/slab.h>
15 #include <linux/err.h>
16 #include <linux/delay.h>
17 #include <linux/pci.h>
18 #include <linux/uaccess.h>
19 #include <asm/pci_debug.h>
20 #include <asm/pci_clp.h>
21 #include <asm/compat.h>
22 #include <asm/clp.h>
23 #include <uapi/asm/clp.h>
24 
25 bool zpci_unique_uid;
26 
27 static inline void zpci_err_clp(unsigned int rsp, int rc)
28 {
29 	struct {
30 		unsigned int rsp;
31 		int rc;
32 	} __packed data = {rsp, rc};
33 
34 	zpci_err_hex(&data, sizeof(data));
35 }
36 
37 /*
38  * Call Logical Processor with c=1, lps=0 and command 1
39  * to get the bit mask of installed logical processors
40  */
41 static inline int clp_get_ilp(unsigned long *ilp)
42 {
43 	unsigned long mask;
44 	int cc = 3;
45 
46 	asm volatile (
47 		"	.insn	rrf,0xb9a00000,%[mask],%[cmd],8,0\n"
48 		"0:	ipm	%[cc]\n"
49 		"	srl	%[cc],28\n"
50 		"1:\n"
51 		EX_TABLE(0b, 1b)
52 		: [cc] "+d" (cc), [mask] "=d" (mask) : [cmd] "a" (1)
53 		: "cc");
54 	*ilp = mask;
55 	return cc;
56 }
57 
58 /*
59  * Call Logical Processor with c=0, the give constant lps and an lpcb request.
60  */
61 static inline int clp_req(void *data, unsigned int lps)
62 {
63 	struct { u8 _[CLP_BLK_SIZE]; } *req = data;
64 	u64 ignored;
65 	int cc = 3;
66 
67 	asm volatile (
68 		"	.insn	rrf,0xb9a00000,%[ign],%[req],0,%[lps]\n"
69 		"0:	ipm	%[cc]\n"
70 		"	srl	%[cc],28\n"
71 		"1:\n"
72 		EX_TABLE(0b, 1b)
73 		: [cc] "+d" (cc), [ign] "=d" (ignored), "+m" (*req)
74 		: [req] "a" (req), [lps] "i" (lps)
75 		: "cc");
76 	return cc;
77 }
78 
79 static void *clp_alloc_block(gfp_t gfp_mask)
80 {
81 	return (void *) __get_free_pages(gfp_mask, get_order(CLP_BLK_SIZE));
82 }
83 
84 static void clp_free_block(void *ptr)
85 {
86 	free_pages((unsigned long) ptr, get_order(CLP_BLK_SIZE));
87 }
88 
89 static void clp_store_query_pci_fngrp(struct zpci_dev *zdev,
90 				      struct clp_rsp_query_pci_grp *response)
91 {
92 	zdev->tlb_refresh = response->refresh;
93 	zdev->dma_mask = response->dasm;
94 	zdev->msi_addr = response->msia;
95 	zdev->max_msi = response->noi;
96 	zdev->fmb_update = response->mui;
97 
98 	switch (response->version) {
99 	case 1:
100 		zdev->max_bus_speed = PCIE_SPEED_5_0GT;
101 		break;
102 	default:
103 		zdev->max_bus_speed = PCI_SPEED_UNKNOWN;
104 		break;
105 	}
106 }
107 
108 static int clp_query_pci_fngrp(struct zpci_dev *zdev, u8 pfgid)
109 {
110 	struct clp_req_rsp_query_pci_grp *rrb;
111 	int rc;
112 
113 	rrb = clp_alloc_block(GFP_KERNEL);
114 	if (!rrb)
115 		return -ENOMEM;
116 
117 	memset(rrb, 0, sizeof(*rrb));
118 	rrb->request.hdr.len = sizeof(rrb->request);
119 	rrb->request.hdr.cmd = CLP_QUERY_PCI_FNGRP;
120 	rrb->response.hdr.len = sizeof(rrb->response);
121 	rrb->request.pfgid = pfgid;
122 
123 	rc = clp_req(rrb, CLP_LPS_PCI);
124 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
125 		clp_store_query_pci_fngrp(zdev, &rrb->response);
126 	else {
127 		zpci_err("Q PCI FGRP:\n");
128 		zpci_err_clp(rrb->response.hdr.rsp, rc);
129 		rc = -EIO;
130 	}
131 	clp_free_block(rrb);
132 	return rc;
133 }
134 
135 static int clp_store_query_pci_fn(struct zpci_dev *zdev,
136 				  struct clp_rsp_query_pci *response)
137 {
138 	int i;
139 
140 	for (i = 0; i < PCI_BAR_COUNT; i++) {
141 		zdev->bars[i].val = le32_to_cpu(response->bar[i]);
142 		zdev->bars[i].size = response->bar_size[i];
143 	}
144 	zdev->start_dma = response->sdma;
145 	zdev->end_dma = response->edma;
146 	zdev->pchid = response->pchid;
147 	zdev->pfgid = response->pfgid;
148 	zdev->pft = response->pft;
149 	zdev->vfn = response->vfn;
150 	zdev->uid = response->uid;
151 	zdev->fmb_length = sizeof(u32) * response->fmb_len;
152 
153 	memcpy(zdev->pfip, response->pfip, sizeof(zdev->pfip));
154 	if (response->util_str_avail) {
155 		memcpy(zdev->util_str, response->util_str,
156 		       sizeof(zdev->util_str));
157 	}
158 
159 	return 0;
160 }
161 
162 static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh)
163 {
164 	struct clp_req_rsp_query_pci *rrb;
165 	int rc;
166 
167 	rrb = clp_alloc_block(GFP_KERNEL);
168 	if (!rrb)
169 		return -ENOMEM;
170 
171 	memset(rrb, 0, sizeof(*rrb));
172 	rrb->request.hdr.len = sizeof(rrb->request);
173 	rrb->request.hdr.cmd = CLP_QUERY_PCI_FN;
174 	rrb->response.hdr.len = sizeof(rrb->response);
175 	rrb->request.fh = fh;
176 
177 	rc = clp_req(rrb, CLP_LPS_PCI);
178 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
179 		rc = clp_store_query_pci_fn(zdev, &rrb->response);
180 		if (rc)
181 			goto out;
182 		rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
183 	} else {
184 		zpci_err("Q PCI FN:\n");
185 		zpci_err_clp(rrb->response.hdr.rsp, rc);
186 		rc = -EIO;
187 	}
188 out:
189 	clp_free_block(rrb);
190 	return rc;
191 }
192 
193 int clp_add_pci_device(u32 fid, u32 fh, int configured)
194 {
195 	struct zpci_dev *zdev;
196 	int rc = -ENOMEM;
197 
198 	zpci_dbg(3, "add fid:%x, fh:%x, c:%d\n", fid, fh, configured);
199 	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
200 	if (!zdev)
201 		goto error;
202 
203 	zdev->fh = fh;
204 	zdev->fid = fid;
205 
206 	/* Query function properties and update zdev */
207 	rc = clp_query_pci_fn(zdev, fh);
208 	if (rc)
209 		goto error;
210 
211 	if (configured)
212 		zdev->state = ZPCI_FN_STATE_CONFIGURED;
213 	else
214 		zdev->state = ZPCI_FN_STATE_STANDBY;
215 
216 	rc = zpci_create_device(zdev);
217 	if (rc)
218 		goto error;
219 	return 0;
220 
221 error:
222 	zpci_dbg(0, "add fid:%x, rc:%d\n", fid, rc);
223 	kfree(zdev);
224 	return rc;
225 }
226 
227 /*
228  * Enable/Disable a given PCI function defined by its function handle.
229  */
230 static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)
231 {
232 	struct clp_req_rsp_set_pci *rrb;
233 	int rc, retries = 100;
234 
235 	rrb = clp_alloc_block(GFP_KERNEL);
236 	if (!rrb)
237 		return -ENOMEM;
238 
239 	do {
240 		memset(rrb, 0, sizeof(*rrb));
241 		rrb->request.hdr.len = sizeof(rrb->request);
242 		rrb->request.hdr.cmd = CLP_SET_PCI_FN;
243 		rrb->response.hdr.len = sizeof(rrb->response);
244 		rrb->request.fh = *fh;
245 		rrb->request.oc = command;
246 		rrb->request.ndas = nr_dma_as;
247 
248 		rc = clp_req(rrb, CLP_LPS_PCI);
249 		if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
250 			retries--;
251 			if (retries < 0)
252 				break;
253 			msleep(20);
254 		}
255 	} while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
256 
257 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
258 		*fh = rrb->response.fh;
259 	else {
260 		zpci_err("Set PCI FN:\n");
261 		zpci_err_clp(rrb->response.hdr.rsp, rc);
262 		rc = -EIO;
263 	}
264 	clp_free_block(rrb);
265 	return rc;
266 }
267 
268 int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
269 {
270 	u32 fh = zdev->fh;
271 	int rc;
272 
273 	rc = clp_set_pci_fn(&fh, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
274 	if (!rc)
275 		/* Success -> store enabled handle in zdev */
276 		zdev->fh = fh;
277 
278 	zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
279 	return rc;
280 }
281 
282 int clp_disable_fh(struct zpci_dev *zdev)
283 {
284 	u32 fh = zdev->fh;
285 	int rc;
286 
287 	if (!zdev_enabled(zdev))
288 		return 0;
289 
290 	rc = clp_set_pci_fn(&fh, 0, CLP_SET_DISABLE_PCI_FN);
291 	if (!rc)
292 		/* Success -> store disabled handle in zdev */
293 		zdev->fh = fh;
294 
295 	zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
296 	return rc;
297 }
298 
299 static int clp_list_pci(struct clp_req_rsp_list_pci *rrb, void *data,
300 			void (*cb)(struct clp_fh_list_entry *, void *))
301 {
302 	u64 resume_token = 0;
303 	int entries, i, rc;
304 
305 	do {
306 		memset(rrb, 0, sizeof(*rrb));
307 		rrb->request.hdr.len = sizeof(rrb->request);
308 		rrb->request.hdr.cmd = CLP_LIST_PCI;
309 		/* store as many entries as possible */
310 		rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
311 		rrb->request.resume_token = resume_token;
312 
313 		/* Get PCI function handle list */
314 		rc = clp_req(rrb, CLP_LPS_PCI);
315 		if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
316 			zpci_err("List PCI FN:\n");
317 			zpci_err_clp(rrb->response.hdr.rsp, rc);
318 			rc = -EIO;
319 			goto out;
320 		}
321 
322 		zpci_unique_uid = rrb->response.uid_checking;
323 		WARN_ON_ONCE(rrb->response.entry_size !=
324 			sizeof(struct clp_fh_list_entry));
325 
326 		entries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
327 			rrb->response.entry_size;
328 
329 		resume_token = rrb->response.resume_token;
330 		for (i = 0; i < entries; i++)
331 			cb(&rrb->response.fh_list[i], data);
332 	} while (resume_token);
333 out:
334 	return rc;
335 }
336 
337 static void __clp_add(struct clp_fh_list_entry *entry, void *data)
338 {
339 	struct zpci_dev *zdev;
340 
341 	if (!entry->vendor_id)
342 		return;
343 
344 	zdev = get_zdev_by_fid(entry->fid);
345 	if (!zdev)
346 		clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
347 }
348 
349 static void __clp_update(struct clp_fh_list_entry *entry, void *data)
350 {
351 	struct zpci_dev *zdev;
352 
353 	if (!entry->vendor_id)
354 		return;
355 
356 	zdev = get_zdev_by_fid(entry->fid);
357 	if (!zdev)
358 		return;
359 
360 	zdev->fh = entry->fh;
361 }
362 
363 int clp_scan_pci_devices(void)
364 {
365 	struct clp_req_rsp_list_pci *rrb;
366 	int rc;
367 
368 	rrb = clp_alloc_block(GFP_KERNEL);
369 	if (!rrb)
370 		return -ENOMEM;
371 
372 	rc = clp_list_pci(rrb, NULL, __clp_add);
373 
374 	clp_free_block(rrb);
375 	return rc;
376 }
377 
378 int clp_rescan_pci_devices(void)
379 {
380 	struct clp_req_rsp_list_pci *rrb;
381 	int rc;
382 
383 	zpci_remove_reserved_devices();
384 
385 	rrb = clp_alloc_block(GFP_KERNEL);
386 	if (!rrb)
387 		return -ENOMEM;
388 
389 	rc = clp_list_pci(rrb, NULL, __clp_add);
390 
391 	clp_free_block(rrb);
392 	return rc;
393 }
394 
395 int clp_rescan_pci_devices_simple(void)
396 {
397 	struct clp_req_rsp_list_pci *rrb;
398 	int rc;
399 
400 	rrb = clp_alloc_block(GFP_NOWAIT);
401 	if (!rrb)
402 		return -ENOMEM;
403 
404 	rc = clp_list_pci(rrb, NULL, __clp_update);
405 
406 	clp_free_block(rrb);
407 	return rc;
408 }
409 
410 struct clp_state_data {
411 	u32 fid;
412 	enum zpci_state state;
413 };
414 
415 static void __clp_get_state(struct clp_fh_list_entry *entry, void *data)
416 {
417 	struct clp_state_data *sd = data;
418 
419 	if (entry->fid != sd->fid)
420 		return;
421 
422 	sd->state = entry->config_state;
423 }
424 
425 int clp_get_state(u32 fid, enum zpci_state *state)
426 {
427 	struct clp_req_rsp_list_pci *rrb;
428 	struct clp_state_data sd = {fid, ZPCI_FN_STATE_RESERVED};
429 	int rc;
430 
431 	rrb = clp_alloc_block(GFP_KERNEL);
432 	if (!rrb)
433 		return -ENOMEM;
434 
435 	rc = clp_list_pci(rrb, &sd, __clp_get_state);
436 	if (!rc)
437 		*state = sd.state;
438 
439 	clp_free_block(rrb);
440 	return rc;
441 }
442 
443 static int clp_base_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
444 {
445 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
446 
447 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
448 	    lpcb->response.hdr.len > limit)
449 		return -EINVAL;
450 	return clp_req(lpcb, CLP_LPS_BASE) ? -EOPNOTSUPP : 0;
451 }
452 
453 static int clp_base_command(struct clp_req *req, struct clp_req_hdr *lpcb)
454 {
455 	switch (lpcb->cmd) {
456 	case 0x0001: /* store logical-processor characteristics */
457 		return clp_base_slpc(req, (void *) lpcb);
458 	default:
459 		return -EINVAL;
460 	}
461 }
462 
463 static int clp_pci_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
464 {
465 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
466 
467 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
468 	    lpcb->response.hdr.len > limit)
469 		return -EINVAL;
470 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
471 }
472 
473 static int clp_pci_list(struct clp_req *req, struct clp_req_rsp_list_pci *lpcb)
474 {
475 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
476 
477 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
478 	    lpcb->response.hdr.len > limit)
479 		return -EINVAL;
480 	if (lpcb->request.reserved2 != 0)
481 		return -EINVAL;
482 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
483 }
484 
485 static int clp_pci_query(struct clp_req *req,
486 			 struct clp_req_rsp_query_pci *lpcb)
487 {
488 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
489 
490 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
491 	    lpcb->response.hdr.len > limit)
492 		return -EINVAL;
493 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0)
494 		return -EINVAL;
495 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
496 }
497 
498 static int clp_pci_query_grp(struct clp_req *req,
499 			     struct clp_req_rsp_query_pci_grp *lpcb)
500 {
501 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
502 
503 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
504 	    lpcb->response.hdr.len > limit)
505 		return -EINVAL;
506 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0 ||
507 	    lpcb->request.reserved4 != 0)
508 		return -EINVAL;
509 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
510 }
511 
512 static int clp_pci_command(struct clp_req *req, struct clp_req_hdr *lpcb)
513 {
514 	switch (lpcb->cmd) {
515 	case 0x0001: /* store logical-processor characteristics */
516 		return clp_pci_slpc(req, (void *) lpcb);
517 	case 0x0002: /* list PCI functions */
518 		return clp_pci_list(req, (void *) lpcb);
519 	case 0x0003: /* query PCI function */
520 		return clp_pci_query(req, (void *) lpcb);
521 	case 0x0004: /* query PCI function group */
522 		return clp_pci_query_grp(req, (void *) lpcb);
523 	default:
524 		return -EINVAL;
525 	}
526 }
527 
528 static int clp_normal_command(struct clp_req *req)
529 {
530 	struct clp_req_hdr *lpcb;
531 	void __user *uptr;
532 	int rc;
533 
534 	rc = -EINVAL;
535 	if (req->lps != 0 && req->lps != 2)
536 		goto out;
537 
538 	rc = -ENOMEM;
539 	lpcb = clp_alloc_block(GFP_KERNEL);
540 	if (!lpcb)
541 		goto out;
542 
543 	rc = -EFAULT;
544 	uptr = (void __force __user *)(unsigned long) req->data_p;
545 	if (copy_from_user(lpcb, uptr, PAGE_SIZE) != 0)
546 		goto out_free;
547 
548 	rc = -EINVAL;
549 	if (lpcb->fmt != 0 || lpcb->reserved1 != 0 || lpcb->reserved2 != 0)
550 		goto out_free;
551 
552 	switch (req->lps) {
553 	case 0:
554 		rc = clp_base_command(req, lpcb);
555 		break;
556 	case 2:
557 		rc = clp_pci_command(req, lpcb);
558 		break;
559 	}
560 	if (rc)
561 		goto out_free;
562 
563 	rc = -EFAULT;
564 	if (copy_to_user(uptr, lpcb, PAGE_SIZE) != 0)
565 		goto out_free;
566 
567 	rc = 0;
568 
569 out_free:
570 	clp_free_block(lpcb);
571 out:
572 	return rc;
573 }
574 
575 static int clp_immediate_command(struct clp_req *req)
576 {
577 	void __user *uptr;
578 	unsigned long ilp;
579 	int exists;
580 
581 	if (req->cmd > 1 || clp_get_ilp(&ilp) != 0)
582 		return -EINVAL;
583 
584 	uptr = (void __force __user *)(unsigned long) req->data_p;
585 	if (req->cmd == 0) {
586 		/* Command code 0: test for a specific processor */
587 		exists = test_bit_inv(req->lps, &ilp);
588 		return put_user(exists, (int __user *) uptr);
589 	}
590 	/* Command code 1: return bit mask of installed processors */
591 	return put_user(ilp, (unsigned long __user *) uptr);
592 }
593 
594 static long clp_misc_ioctl(struct file *filp, unsigned int cmd,
595 			   unsigned long arg)
596 {
597 	struct clp_req req;
598 	void __user *argp;
599 
600 	if (cmd != CLP_SYNC)
601 		return -EINVAL;
602 
603 	argp = is_compat_task() ? compat_ptr(arg) : (void __user *) arg;
604 	if (copy_from_user(&req, argp, sizeof(req)))
605 		return -EFAULT;
606 	if (req.r != 0)
607 		return -EINVAL;
608 	return req.c ? clp_immediate_command(&req) : clp_normal_command(&req);
609 }
610 
611 static int clp_misc_release(struct inode *inode, struct file *filp)
612 {
613 	return 0;
614 }
615 
616 static const struct file_operations clp_misc_fops = {
617 	.owner = THIS_MODULE,
618 	.open = nonseekable_open,
619 	.release = clp_misc_release,
620 	.unlocked_ioctl = clp_misc_ioctl,
621 	.compat_ioctl = clp_misc_ioctl,
622 	.llseek = no_llseek,
623 };
624 
625 static struct miscdevice clp_misc_device = {
626 	.minor = MISC_DYNAMIC_MINOR,
627 	.name = "clp",
628 	.fops = &clp_misc_fops,
629 };
630 
631 static int __init clp_misc_init(void)
632 {
633 	return misc_register(&clp_misc_device);
634 }
635 
636 device_initcall(clp_misc_init);
637