xref: /kernel/linux/linux-5.10/arch/s390/pci/pci_clp.c (revision 8c2ecf20)
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#include "pci_bus.h"
26
27bool zpci_unique_uid;
28
29void update_uid_checking(bool new)
30{
31	if (zpci_unique_uid != new)
32		zpci_dbg(1, "uid checking:%d\n", new);
33
34	zpci_unique_uid = new;
35}
36
37static inline void zpci_err_clp(unsigned int rsp, int rc)
38{
39	struct {
40		unsigned int rsp;
41		int rc;
42	} __packed data = {rsp, rc};
43
44	zpci_err_hex(&data, sizeof(data));
45}
46
47/*
48 * Call Logical Processor with c=1, lps=0 and command 1
49 * to get the bit mask of installed logical processors
50 */
51static inline int clp_get_ilp(unsigned long *ilp)
52{
53	unsigned long mask;
54	int cc = 3;
55
56	asm volatile (
57		"	.insn	rrf,0xb9a00000,%[mask],%[cmd],8,0\n"
58		"0:	ipm	%[cc]\n"
59		"	srl	%[cc],28\n"
60		"1:\n"
61		EX_TABLE(0b, 1b)
62		: [cc] "+d" (cc), [mask] "=d" (mask) : [cmd] "a" (1)
63		: "cc");
64	*ilp = mask;
65	return cc;
66}
67
68/*
69 * Call Logical Processor with c=0, the give constant lps and an lpcb request.
70 */
71static __always_inline int clp_req(void *data, unsigned int lps)
72{
73	struct { u8 _[CLP_BLK_SIZE]; } *req = data;
74	u64 ignored;
75	int cc = 3;
76
77	asm volatile (
78		"	.insn	rrf,0xb9a00000,%[ign],%[req],0,%[lps]\n"
79		"0:	ipm	%[cc]\n"
80		"	srl	%[cc],28\n"
81		"1:\n"
82		EX_TABLE(0b, 1b)
83		: [cc] "+d" (cc), [ign] "=d" (ignored), "+m" (*req)
84		: [req] "a" (req), [lps] "i" (lps)
85		: "cc");
86	return cc;
87}
88
89static void *clp_alloc_block(gfp_t gfp_mask)
90{
91	return (void *) __get_free_pages(gfp_mask, get_order(CLP_BLK_SIZE));
92}
93
94static void clp_free_block(void *ptr)
95{
96	free_pages((unsigned long) ptr, get_order(CLP_BLK_SIZE));
97}
98
99static void clp_store_query_pci_fngrp(struct zpci_dev *zdev,
100				      struct clp_rsp_query_pci_grp *response)
101{
102	zdev->tlb_refresh = response->refresh;
103	zdev->dma_mask = response->dasm;
104	zdev->msi_addr = response->msia;
105	zdev->max_msi = response->noi;
106	zdev->fmb_update = response->mui;
107	zdev->version = response->version;
108
109	switch (response->version) {
110	case 1:
111		zdev->max_bus_speed = PCIE_SPEED_5_0GT;
112		break;
113	default:
114		zdev->max_bus_speed = PCI_SPEED_UNKNOWN;
115		break;
116	}
117}
118
119static int clp_query_pci_fngrp(struct zpci_dev *zdev, u8 pfgid)
120{
121	struct clp_req_rsp_query_pci_grp *rrb;
122	int rc;
123
124	rrb = clp_alloc_block(GFP_KERNEL);
125	if (!rrb)
126		return -ENOMEM;
127
128	memset(rrb, 0, sizeof(*rrb));
129	rrb->request.hdr.len = sizeof(rrb->request);
130	rrb->request.hdr.cmd = CLP_QUERY_PCI_FNGRP;
131	rrb->response.hdr.len = sizeof(rrb->response);
132	rrb->request.pfgid = pfgid;
133
134	rc = clp_req(rrb, CLP_LPS_PCI);
135	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
136		clp_store_query_pci_fngrp(zdev, &rrb->response);
137	else {
138		zpci_err("Q PCI FGRP:\n");
139		zpci_err_clp(rrb->response.hdr.rsp, rc);
140		rc = -EIO;
141	}
142	clp_free_block(rrb);
143	return rc;
144}
145
146static int clp_store_query_pci_fn(struct zpci_dev *zdev,
147				  struct clp_rsp_query_pci *response)
148{
149	int i;
150
151	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
152		zdev->bars[i].val = le32_to_cpu(response->bar[i]);
153		zdev->bars[i].size = response->bar_size[i];
154	}
155	zdev->start_dma = response->sdma;
156	zdev->end_dma = response->edma;
157	zdev->pchid = response->pchid;
158	zdev->pfgid = response->pfgid;
159	zdev->pft = response->pft;
160	zdev->vfn = response->vfn;
161	zdev->port = response->port;
162	zdev->uid = response->uid;
163	zdev->fmb_length = sizeof(u32) * response->fmb_len;
164	zdev->rid_available = response->rid_avail;
165	zdev->is_physfn = response->is_physfn;
166	if (!s390_pci_no_rid && zdev->rid_available)
167		zdev->devfn = response->rid & ZPCI_RID_MASK_DEVFN;
168
169	memcpy(zdev->pfip, response->pfip, sizeof(zdev->pfip));
170	if (response->util_str_avail) {
171		memcpy(zdev->util_str, response->util_str,
172		       sizeof(zdev->util_str));
173		zdev->util_str_avail = 1;
174	}
175	zdev->mio_capable = response->mio_addr_avail;
176	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
177		if (!(response->mio.valid & (1 << (PCI_STD_NUM_BARS - i - 1))))
178			continue;
179
180		zdev->bars[i].mio_wb = (void __iomem *) response->mio.addr[i].wb;
181		zdev->bars[i].mio_wt = (void __iomem *) response->mio.addr[i].wt;
182	}
183	return 0;
184}
185
186int clp_query_pci_fn(struct zpci_dev *zdev)
187{
188	struct clp_req_rsp_query_pci *rrb;
189	int rc;
190
191	rrb = clp_alloc_block(GFP_KERNEL);
192	if (!rrb)
193		return -ENOMEM;
194
195	memset(rrb, 0, sizeof(*rrb));
196	rrb->request.hdr.len = sizeof(rrb->request);
197	rrb->request.hdr.cmd = CLP_QUERY_PCI_FN;
198	rrb->response.hdr.len = sizeof(rrb->response);
199	rrb->request.fh = zdev->fh;
200
201	rc = clp_req(rrb, CLP_LPS_PCI);
202	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
203		rc = clp_store_query_pci_fn(zdev, &rrb->response);
204		if (rc)
205			goto out;
206		rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
207	} else {
208		zpci_err("Q PCI FN:\n");
209		zpci_err_clp(rrb->response.hdr.rsp, rc);
210		rc = -EIO;
211	}
212out:
213	clp_free_block(rrb);
214	return rc;
215}
216
217static int clp_refresh_fh(u32 fid);
218/**
219 * clp_set_pci_fn() - Execute a command on a PCI function
220 * @zdev: Function that will be affected
221 * @nr_dma_as: DMA address space number
222 * @command: The command code to execute
223 *
224 * Returns: 0 on success, < 0 for Linux errors (e.g. -ENOMEM), and
225 * > 0 for non-success platform responses
226 */
227static int clp_set_pci_fn(struct zpci_dev *zdev, u8 nr_dma_as, u8 command)
228{
229	struct clp_req_rsp_set_pci *rrb;
230	int rc, retries = 100;
231
232	rrb = clp_alloc_block(GFP_KERNEL);
233	if (!rrb)
234		return -ENOMEM;
235
236	do {
237		memset(rrb, 0, sizeof(*rrb));
238		rrb->request.hdr.len = sizeof(rrb->request);
239		rrb->request.hdr.cmd = CLP_SET_PCI_FN;
240		rrb->response.hdr.len = sizeof(rrb->response);
241		rrb->request.fh = zdev->fh;
242		rrb->request.oc = command;
243		rrb->request.ndas = nr_dma_as;
244
245		rc = clp_req(rrb, CLP_LPS_PCI);
246		if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
247			retries--;
248			if (retries < 0)
249				break;
250			msleep(20);
251		}
252	} while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
253
254	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
255		zdev->fh = rrb->response.fh;
256	} else if (!rc && rrb->response.hdr.rsp == CLP_RC_SETPCIFN_ALRDY) {
257		/* Function is already in desired state - update handle */
258		rc = clp_refresh_fh(zdev->fid);
259	} else {
260		zpci_err("Set PCI FN:\n");
261		zpci_err_clp(rrb->response.hdr.rsp, rc);
262		if (!rc)
263			rc = rrb->response.hdr.rsp;
264	}
265	clp_free_block(rrb);
266	return rc;
267}
268
269int clp_setup_writeback_mio(void)
270{
271	struct clp_req_rsp_slpc_pci *rrb;
272	u8  wb_bit_pos;
273	int rc;
274
275	rrb = clp_alloc_block(GFP_KERNEL);
276	if (!rrb)
277		return -ENOMEM;
278
279	memset(rrb, 0, sizeof(*rrb));
280	rrb->request.hdr.len = sizeof(rrb->request);
281	rrb->request.hdr.cmd = CLP_SLPC;
282	rrb->response.hdr.len = sizeof(rrb->response);
283
284	rc = clp_req(rrb, CLP_LPS_PCI);
285	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
286		if (rrb->response.vwb) {
287			wb_bit_pos = rrb->response.mio_wb;
288			set_bit_inv(wb_bit_pos, &mio_wb_bit_mask);
289			zpci_dbg(3, "wb bit: %d\n", wb_bit_pos);
290		} else {
291			zpci_dbg(3, "wb bit: n.a.\n");
292		}
293
294	} else {
295		zpci_err("SLPC PCI:\n");
296		zpci_err_clp(rrb->response.hdr.rsp, rc);
297		rc = -EIO;
298	}
299	clp_free_block(rrb);
300	return rc;
301}
302
303int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
304{
305	int rc;
306
307	rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
308	zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
309	if (!rc && zpci_use_mio(zdev)) {
310		rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_MIO);
311		zpci_dbg(3, "ena mio fid:%x, fh:%x, rc:%d\n",
312				zdev->fid, zdev->fh, rc);
313		if (rc)
314			clp_disable_fh(zdev);
315	}
316	return rc;
317}
318
319int clp_disable_fh(struct zpci_dev *zdev)
320{
321	int rc;
322
323	if (!zdev_enabled(zdev))
324		return 0;
325
326	rc = clp_set_pci_fn(zdev, 0, CLP_SET_DISABLE_PCI_FN);
327	zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
328	return rc;
329}
330
331static int clp_list_pci(struct clp_req_rsp_list_pci *rrb, void *data,
332			void (*cb)(struct clp_fh_list_entry *, void *))
333{
334	u64 resume_token = 0;
335	int entries, i, rc;
336
337	do {
338		memset(rrb, 0, sizeof(*rrb));
339		rrb->request.hdr.len = sizeof(rrb->request);
340		rrb->request.hdr.cmd = CLP_LIST_PCI;
341		/* store as many entries as possible */
342		rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
343		rrb->request.resume_token = resume_token;
344
345		/* Get PCI function handle list */
346		rc = clp_req(rrb, CLP_LPS_PCI);
347		if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
348			zpci_err("List PCI FN:\n");
349			zpci_err_clp(rrb->response.hdr.rsp, rc);
350			rc = -EIO;
351			goto out;
352		}
353
354		update_uid_checking(rrb->response.uid_checking);
355		WARN_ON_ONCE(rrb->response.entry_size !=
356			sizeof(struct clp_fh_list_entry));
357
358		entries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
359			rrb->response.entry_size;
360
361		resume_token = rrb->response.resume_token;
362		for (i = 0; i < entries; i++)
363			cb(&rrb->response.fh_list[i], data);
364	} while (resume_token);
365out:
366	return rc;
367}
368
369static void __clp_add(struct clp_fh_list_entry *entry, void *data)
370{
371	struct zpci_dev *zdev;
372
373	if (!entry->vendor_id)
374		return;
375
376	zdev = get_zdev_by_fid(entry->fid);
377	if (zdev) {
378		zpci_zdev_put(zdev);
379		return;
380	}
381	zpci_create_device(entry->fid, entry->fh, entry->config_state);
382}
383
384int 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
399static void __clp_refresh_fh(struct clp_fh_list_entry *entry, void *data)
400{
401	struct zpci_dev *zdev;
402	u32 fid = *((u32 *)data);
403
404	if (!entry->vendor_id || fid != entry->fid)
405		return;
406
407	zdev = get_zdev_by_fid(fid);
408	if (!zdev)
409		return;
410
411	zdev->fh = entry->fh;
412}
413
414/*
415 * Refresh the function handle of the function matching @fid
416 */
417static int clp_refresh_fh(u32 fid)
418{
419	struct clp_req_rsp_list_pci *rrb;
420	int rc;
421
422	rrb = clp_alloc_block(GFP_NOWAIT);
423	if (!rrb)
424		return -ENOMEM;
425
426	rc = clp_list_pci(rrb, &fid, __clp_refresh_fh);
427
428	clp_free_block(rrb);
429	return rc;
430}
431
432struct clp_state_data {
433	u32 fid;
434	enum zpci_state state;
435};
436
437static void __clp_get_state(struct clp_fh_list_entry *entry, void *data)
438{
439	struct clp_state_data *sd = data;
440
441	if (entry->fid != sd->fid)
442		return;
443
444	sd->state = entry->config_state;
445}
446
447int clp_get_state(u32 fid, enum zpci_state *state)
448{
449	struct clp_req_rsp_list_pci *rrb;
450	struct clp_state_data sd = {fid, ZPCI_FN_STATE_RESERVED};
451	int rc;
452
453	rrb = clp_alloc_block(GFP_ATOMIC);
454	if (!rrb)
455		return -ENOMEM;
456
457	rc = clp_list_pci(rrb, &sd, __clp_get_state);
458	if (!rc)
459		*state = sd.state;
460
461	clp_free_block(rrb);
462	return rc;
463}
464
465static int clp_base_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
466{
467	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
468
469	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
470	    lpcb->response.hdr.len > limit)
471		return -EINVAL;
472	return clp_req(lpcb, CLP_LPS_BASE) ? -EOPNOTSUPP : 0;
473}
474
475static int clp_base_command(struct clp_req *req, struct clp_req_hdr *lpcb)
476{
477	switch (lpcb->cmd) {
478	case 0x0001: /* store logical-processor characteristics */
479		return clp_base_slpc(req, (void *) lpcb);
480	default:
481		return -EINVAL;
482	}
483}
484
485static int clp_pci_slpc(struct clp_req *req, struct clp_req_rsp_slpc_pci *lpcb)
486{
487	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
488
489	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
490	    lpcb->response.hdr.len > limit)
491		return -EINVAL;
492	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
493}
494
495static int clp_pci_list(struct clp_req *req, struct clp_req_rsp_list_pci *lpcb)
496{
497	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
498
499	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
500	    lpcb->response.hdr.len > limit)
501		return -EINVAL;
502	if (lpcb->request.reserved2 != 0)
503		return -EINVAL;
504	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
505}
506
507static int clp_pci_query(struct clp_req *req,
508			 struct clp_req_rsp_query_pci *lpcb)
509{
510	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
511
512	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
513	    lpcb->response.hdr.len > limit)
514		return -EINVAL;
515	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0)
516		return -EINVAL;
517	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
518}
519
520static int clp_pci_query_grp(struct clp_req *req,
521			     struct clp_req_rsp_query_pci_grp *lpcb)
522{
523	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
524
525	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
526	    lpcb->response.hdr.len > limit)
527		return -EINVAL;
528	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0 ||
529	    lpcb->request.reserved4 != 0)
530		return -EINVAL;
531	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
532}
533
534static int clp_pci_command(struct clp_req *req, struct clp_req_hdr *lpcb)
535{
536	switch (lpcb->cmd) {
537	case 0x0001: /* store logical-processor characteristics */
538		return clp_pci_slpc(req, (void *) lpcb);
539	case 0x0002: /* list PCI functions */
540		return clp_pci_list(req, (void *) lpcb);
541	case 0x0003: /* query PCI function */
542		return clp_pci_query(req, (void *) lpcb);
543	case 0x0004: /* query PCI function group */
544		return clp_pci_query_grp(req, (void *) lpcb);
545	default:
546		return -EINVAL;
547	}
548}
549
550static int clp_normal_command(struct clp_req *req)
551{
552	struct clp_req_hdr *lpcb;
553	void __user *uptr;
554	int rc;
555
556	rc = -EINVAL;
557	if (req->lps != 0 && req->lps != 2)
558		goto out;
559
560	rc = -ENOMEM;
561	lpcb = clp_alloc_block(GFP_KERNEL);
562	if (!lpcb)
563		goto out;
564
565	rc = -EFAULT;
566	uptr = (void __force __user *)(unsigned long) req->data_p;
567	if (copy_from_user(lpcb, uptr, PAGE_SIZE) != 0)
568		goto out_free;
569
570	rc = -EINVAL;
571	if (lpcb->fmt != 0 || lpcb->reserved1 != 0 || lpcb->reserved2 != 0)
572		goto out_free;
573
574	switch (req->lps) {
575	case 0:
576		rc = clp_base_command(req, lpcb);
577		break;
578	case 2:
579		rc = clp_pci_command(req, lpcb);
580		break;
581	}
582	if (rc)
583		goto out_free;
584
585	rc = -EFAULT;
586	if (copy_to_user(uptr, lpcb, PAGE_SIZE) != 0)
587		goto out_free;
588
589	rc = 0;
590
591out_free:
592	clp_free_block(lpcb);
593out:
594	return rc;
595}
596
597static int clp_immediate_command(struct clp_req *req)
598{
599	void __user *uptr;
600	unsigned long ilp;
601	int exists;
602
603	if (req->cmd > 1 || clp_get_ilp(&ilp) != 0)
604		return -EINVAL;
605
606	uptr = (void __force __user *)(unsigned long) req->data_p;
607	if (req->cmd == 0) {
608		/* Command code 0: test for a specific processor */
609		exists = test_bit_inv(req->lps, &ilp);
610		return put_user(exists, (int __user *) uptr);
611	}
612	/* Command code 1: return bit mask of installed processors */
613	return put_user(ilp, (unsigned long __user *) uptr);
614}
615
616static long clp_misc_ioctl(struct file *filp, unsigned int cmd,
617			   unsigned long arg)
618{
619	struct clp_req req;
620	void __user *argp;
621
622	if (cmd != CLP_SYNC)
623		return -EINVAL;
624
625	argp = is_compat_task() ? compat_ptr(arg) : (void __user *) arg;
626	if (copy_from_user(&req, argp, sizeof(req)))
627		return -EFAULT;
628	if (req.r != 0)
629		return -EINVAL;
630	return req.c ? clp_immediate_command(&req) : clp_normal_command(&req);
631}
632
633static int clp_misc_release(struct inode *inode, struct file *filp)
634{
635	return 0;
636}
637
638static const struct file_operations clp_misc_fops = {
639	.owner = THIS_MODULE,
640	.open = nonseekable_open,
641	.release = clp_misc_release,
642	.unlocked_ioctl = clp_misc_ioctl,
643	.compat_ioctl = clp_misc_ioctl,
644	.llseek = no_llseek,
645};
646
647static struct miscdevice clp_misc_device = {
648	.minor = MISC_DYNAMIC_MINOR,
649	.name = "clp",
650	.fops = &clp_misc_fops,
651};
652
653static int __init clp_misc_init(void)
654{
655	return misc_register(&clp_misc_device);
656}
657
658device_initcall(clp_misc_init);
659