xref: /openbmc/linux/arch/s390/pci/pci_clp.c (revision 79a93295)
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;
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 		return -ENOMEM;
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 	kfree(zdev);
223 	return rc;
224 }
225 
226 /*
227  * Enable/Disable a given PCI function defined by its function handle.
228  */
229 static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)
230 {
231 	struct clp_req_rsp_set_pci *rrb;
232 	int rc, retries = 100;
233 
234 	rrb = clp_alloc_block(GFP_KERNEL);
235 	if (!rrb)
236 		return -ENOMEM;
237 
238 	do {
239 		memset(rrb, 0, sizeof(*rrb));
240 		rrb->request.hdr.len = sizeof(rrb->request);
241 		rrb->request.hdr.cmd = CLP_SET_PCI_FN;
242 		rrb->response.hdr.len = sizeof(rrb->response);
243 		rrb->request.fh = *fh;
244 		rrb->request.oc = command;
245 		rrb->request.ndas = nr_dma_as;
246 
247 		rc = clp_req(rrb, CLP_LPS_PCI);
248 		if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
249 			retries--;
250 			if (retries < 0)
251 				break;
252 			msleep(20);
253 		}
254 	} while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
255 
256 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
257 		*fh = rrb->response.fh;
258 	else {
259 		zpci_err("Set PCI FN:\n");
260 		zpci_err_clp(rrb->response.hdr.rsp, rc);
261 		rc = -EIO;
262 	}
263 	clp_free_block(rrb);
264 	return rc;
265 }
266 
267 int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
268 {
269 	u32 fh = zdev->fh;
270 	int rc;
271 
272 	rc = clp_set_pci_fn(&fh, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
273 	if (!rc)
274 		/* Success -> store enabled handle in zdev */
275 		zdev->fh = fh;
276 
277 	zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
278 	return rc;
279 }
280 
281 int clp_disable_fh(struct zpci_dev *zdev)
282 {
283 	u32 fh = zdev->fh;
284 	int rc;
285 
286 	if (!zdev_enabled(zdev))
287 		return 0;
288 
289 	rc = clp_set_pci_fn(&fh, 0, CLP_SET_DISABLE_PCI_FN);
290 	if (!rc)
291 		/* Success -> store disabled handle in zdev */
292 		zdev->fh = fh;
293 
294 	zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
295 	return rc;
296 }
297 
298 static int clp_list_pci(struct clp_req_rsp_list_pci *rrb,
299 			void (*cb)(struct clp_fh_list_entry *entry))
300 {
301 	u64 resume_token = 0;
302 	int entries, i, rc;
303 
304 	do {
305 		memset(rrb, 0, sizeof(*rrb));
306 		rrb->request.hdr.len = sizeof(rrb->request);
307 		rrb->request.hdr.cmd = CLP_LIST_PCI;
308 		/* store as many entries as possible */
309 		rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
310 		rrb->request.resume_token = resume_token;
311 
312 		/* Get PCI function handle list */
313 		rc = clp_req(rrb, CLP_LPS_PCI);
314 		if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
315 			zpci_err("List PCI FN:\n");
316 			zpci_err_clp(rrb->response.hdr.rsp, rc);
317 			rc = -EIO;
318 			goto out;
319 		}
320 
321 		zpci_unique_uid = rrb->response.uid_checking;
322 		WARN_ON_ONCE(rrb->response.entry_size !=
323 			sizeof(struct clp_fh_list_entry));
324 
325 		entries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
326 			rrb->response.entry_size;
327 
328 		resume_token = rrb->response.resume_token;
329 		for (i = 0; i < entries; i++)
330 			cb(&rrb->response.fh_list[i]);
331 	} while (resume_token);
332 out:
333 	return rc;
334 }
335 
336 static void __clp_add(struct clp_fh_list_entry *entry)
337 {
338 	if (!entry->vendor_id)
339 		return;
340 
341 	clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
342 }
343 
344 static void __clp_rescan(struct clp_fh_list_entry *entry)
345 {
346 	struct zpci_dev *zdev;
347 
348 	if (!entry->vendor_id)
349 		return;
350 
351 	zdev = get_zdev_by_fid(entry->fid);
352 	if (!zdev) {
353 		clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
354 		return;
355 	}
356 
357 	if (!entry->config_state) {
358 		/*
359 		 * The handle is already disabled, that means no iota/irq freeing via
360 		 * the firmware interfaces anymore. Need to free resources manually
361 		 * (DMA memory, debug, sysfs)...
362 		 */
363 		zpci_stop_device(zdev);
364 	}
365 }
366 
367 static void __clp_update(struct clp_fh_list_entry *entry)
368 {
369 	struct zpci_dev *zdev;
370 
371 	if (!entry->vendor_id)
372 		return;
373 
374 	zdev = get_zdev_by_fid(entry->fid);
375 	if (!zdev)
376 		return;
377 
378 	zdev->fh = entry->fh;
379 }
380 
381 int clp_scan_pci_devices(void)
382 {
383 	struct clp_req_rsp_list_pci *rrb;
384 	int rc;
385 
386 	rrb = clp_alloc_block(GFP_KERNEL);
387 	if (!rrb)
388 		return -ENOMEM;
389 
390 	rc = clp_list_pci(rrb, __clp_add);
391 
392 	clp_free_block(rrb);
393 	return rc;
394 }
395 
396 int clp_rescan_pci_devices(void)
397 {
398 	struct clp_req_rsp_list_pci *rrb;
399 	int rc;
400 
401 	rrb = clp_alloc_block(GFP_KERNEL);
402 	if (!rrb)
403 		return -ENOMEM;
404 
405 	rc = clp_list_pci(rrb, __clp_rescan);
406 
407 	clp_free_block(rrb);
408 	return rc;
409 }
410 
411 int clp_rescan_pci_devices_simple(void)
412 {
413 	struct clp_req_rsp_list_pci *rrb;
414 	int rc;
415 
416 	rrb = clp_alloc_block(GFP_NOWAIT);
417 	if (!rrb)
418 		return -ENOMEM;
419 
420 	rc = clp_list_pci(rrb, __clp_update);
421 
422 	clp_free_block(rrb);
423 	return rc;
424 }
425 
426 static int clp_base_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
427 {
428 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
429 
430 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
431 	    lpcb->response.hdr.len > limit)
432 		return -EINVAL;
433 	return clp_req(lpcb, CLP_LPS_BASE) ? -EOPNOTSUPP : 0;
434 }
435 
436 static int clp_base_command(struct clp_req *req, struct clp_req_hdr *lpcb)
437 {
438 	switch (lpcb->cmd) {
439 	case 0x0001: /* store logical-processor characteristics */
440 		return clp_base_slpc(req, (void *) lpcb);
441 	default:
442 		return -EINVAL;
443 	}
444 }
445 
446 static int clp_pci_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
447 {
448 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
449 
450 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
451 	    lpcb->response.hdr.len > limit)
452 		return -EINVAL;
453 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
454 }
455 
456 static int clp_pci_list(struct clp_req *req, struct clp_req_rsp_list_pci *lpcb)
457 {
458 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
459 
460 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
461 	    lpcb->response.hdr.len > limit)
462 		return -EINVAL;
463 	if (lpcb->request.reserved2 != 0)
464 		return -EINVAL;
465 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
466 }
467 
468 static int clp_pci_query(struct clp_req *req,
469 			 struct clp_req_rsp_query_pci *lpcb)
470 {
471 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
472 
473 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
474 	    lpcb->response.hdr.len > limit)
475 		return -EINVAL;
476 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0)
477 		return -EINVAL;
478 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
479 }
480 
481 static int clp_pci_query_grp(struct clp_req *req,
482 			     struct clp_req_rsp_query_pci_grp *lpcb)
483 {
484 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
485 
486 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
487 	    lpcb->response.hdr.len > limit)
488 		return -EINVAL;
489 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0 ||
490 	    lpcb->request.reserved4 != 0)
491 		return -EINVAL;
492 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
493 }
494 
495 static int clp_pci_command(struct clp_req *req, struct clp_req_hdr *lpcb)
496 {
497 	switch (lpcb->cmd) {
498 	case 0x0001: /* store logical-processor characteristics */
499 		return clp_pci_slpc(req, (void *) lpcb);
500 	case 0x0002: /* list PCI functions */
501 		return clp_pci_list(req, (void *) lpcb);
502 	case 0x0003: /* query PCI function */
503 		return clp_pci_query(req, (void *) lpcb);
504 	case 0x0004: /* query PCI function group */
505 		return clp_pci_query_grp(req, (void *) lpcb);
506 	default:
507 		return -EINVAL;
508 	}
509 }
510 
511 static int clp_normal_command(struct clp_req *req)
512 {
513 	struct clp_req_hdr *lpcb;
514 	void __user *uptr;
515 	int rc;
516 
517 	rc = -EINVAL;
518 	if (req->lps != 0 && req->lps != 2)
519 		goto out;
520 
521 	rc = -ENOMEM;
522 	lpcb = clp_alloc_block(GFP_KERNEL);
523 	if (!lpcb)
524 		goto out;
525 
526 	rc = -EFAULT;
527 	uptr = (void __force __user *)(unsigned long) req->data_p;
528 	if (copy_from_user(lpcb, uptr, PAGE_SIZE) != 0)
529 		goto out_free;
530 
531 	rc = -EINVAL;
532 	if (lpcb->fmt != 0 || lpcb->reserved1 != 0 || lpcb->reserved2 != 0)
533 		goto out_free;
534 
535 	switch (req->lps) {
536 	case 0:
537 		rc = clp_base_command(req, lpcb);
538 		break;
539 	case 2:
540 		rc = clp_pci_command(req, lpcb);
541 		break;
542 	}
543 	if (rc)
544 		goto out_free;
545 
546 	rc = -EFAULT;
547 	if (copy_to_user(uptr, lpcb, PAGE_SIZE) != 0)
548 		goto out_free;
549 
550 	rc = 0;
551 
552 out_free:
553 	clp_free_block(lpcb);
554 out:
555 	return rc;
556 }
557 
558 static int clp_immediate_command(struct clp_req *req)
559 {
560 	void __user *uptr;
561 	unsigned long ilp;
562 	int exists;
563 
564 	if (req->cmd > 1 || clp_get_ilp(&ilp) != 0)
565 		return -EINVAL;
566 
567 	uptr = (void __force __user *)(unsigned long) req->data_p;
568 	if (req->cmd == 0) {
569 		/* Command code 0: test for a specific processor */
570 		exists = test_bit_inv(req->lps, &ilp);
571 		return put_user(exists, (int __user *) uptr);
572 	}
573 	/* Command code 1: return bit mask of installed processors */
574 	return put_user(ilp, (unsigned long __user *) uptr);
575 }
576 
577 static long clp_misc_ioctl(struct file *filp, unsigned int cmd,
578 			   unsigned long arg)
579 {
580 	struct clp_req req;
581 	void __user *argp;
582 
583 	if (cmd != CLP_SYNC)
584 		return -EINVAL;
585 
586 	argp = is_compat_task() ? compat_ptr(arg) : (void __user *) arg;
587 	if (copy_from_user(&req, argp, sizeof(req)))
588 		return -EFAULT;
589 	if (req.r != 0)
590 		return -EINVAL;
591 	return req.c ? clp_immediate_command(&req) : clp_normal_command(&req);
592 }
593 
594 static int clp_misc_release(struct inode *inode, struct file *filp)
595 {
596 	return 0;
597 }
598 
599 static const struct file_operations clp_misc_fops = {
600 	.owner = THIS_MODULE,
601 	.open = nonseekable_open,
602 	.release = clp_misc_release,
603 	.unlocked_ioctl = clp_misc_ioctl,
604 	.compat_ioctl = clp_misc_ioctl,
605 	.llseek = no_llseek,
606 };
607 
608 static struct miscdevice clp_misc_device = {
609 	.minor = MISC_DYNAMIC_MINOR,
610 	.name = "clp",
611 	.fops = &clp_misc_fops,
612 };
613 
614 static int __init clp_misc_init(void)
615 {
616 	return misc_register(&clp_misc_device);
617 }
618 
619 device_initcall(clp_misc_init);
620