treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / pci / vpd.c
blob7915d10f9aa103813c40709d87f014d229b25c8d
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * PCI VPD support
5 * Copyright (C) 2010 Broadcom Corporation.
6 */
8 #include <linux/pci.h>
9 #include <linux/delay.h>
10 #include <linux/export.h>
11 #include <linux/sched/signal.h>
12 #include "pci.h"
14 /* VPD access through PCI 2.2+ VPD capability */
16 struct pci_vpd_ops {
17 ssize_t (*read)(struct pci_dev *dev, loff_t pos, size_t count, void *buf);
18 ssize_t (*write)(struct pci_dev *dev, loff_t pos, size_t count, const void *buf);
19 int (*set_size)(struct pci_dev *dev, size_t len);
22 struct pci_vpd {
23 const struct pci_vpd_ops *ops;
24 struct bin_attribute *attr; /* Descriptor for sysfs VPD entry */
25 struct mutex lock;
26 unsigned int len;
27 u16 flag;
28 u8 cap;
29 unsigned int busy:1;
30 unsigned int valid:1;
33 /**
34 * pci_read_vpd - Read one entry from Vital Product Data
35 * @dev: pci device struct
36 * @pos: offset in vpd space
37 * @count: number of bytes to read
38 * @buf: pointer to where to store result
40 ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf)
42 if (!dev->vpd || !dev->vpd->ops)
43 return -ENODEV;
44 return dev->vpd->ops->read(dev, pos, count, buf);
46 EXPORT_SYMBOL(pci_read_vpd);
48 /**
49 * pci_write_vpd - Write entry to Vital Product Data
50 * @dev: pci device struct
51 * @pos: offset in vpd space
52 * @count: number of bytes to write
53 * @buf: buffer containing write data
55 ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const void *buf)
57 if (!dev->vpd || !dev->vpd->ops)
58 return -ENODEV;
59 return dev->vpd->ops->write(dev, pos, count, buf);
61 EXPORT_SYMBOL(pci_write_vpd);
63 /**
64 * pci_set_vpd_size - Set size of Vital Product Data space
65 * @dev: pci device struct
66 * @len: size of vpd space
68 int pci_set_vpd_size(struct pci_dev *dev, size_t len)
70 if (!dev->vpd || !dev->vpd->ops)
71 return -ENODEV;
72 return dev->vpd->ops->set_size(dev, len);
74 EXPORT_SYMBOL(pci_set_vpd_size);
76 #define PCI_VPD_MAX_SIZE (PCI_VPD_ADDR_MASK + 1)
78 /**
79 * pci_vpd_size - determine actual size of Vital Product Data
80 * @dev: pci device struct
81 * @old_size: current assumed size, also maximum allowed size
83 static size_t pci_vpd_size(struct pci_dev *dev, size_t old_size)
85 size_t off = 0;
86 unsigned char header[1+2]; /* 1 byte tag, 2 bytes length */
88 while (off < old_size &&
89 pci_read_vpd(dev, off, 1, header) == 1) {
90 unsigned char tag;
92 if (header[0] & PCI_VPD_LRDT) {
93 /* Large Resource Data Type Tag */
94 tag = pci_vpd_lrdt_tag(header);
95 /* Only read length from known tag items */
96 if ((tag == PCI_VPD_LTIN_ID_STRING) ||
97 (tag == PCI_VPD_LTIN_RO_DATA) ||
98 (tag == PCI_VPD_LTIN_RW_DATA)) {
99 if (pci_read_vpd(dev, off+1, 2,
100 &header[1]) != 2) {
101 pci_warn(dev, "invalid large VPD tag %02x size at offset %zu",
102 tag, off + 1);
103 return 0;
105 off += PCI_VPD_LRDT_TAG_SIZE +
106 pci_vpd_lrdt_size(header);
108 } else {
109 /* Short Resource Data Type Tag */
110 off += PCI_VPD_SRDT_TAG_SIZE +
111 pci_vpd_srdt_size(header);
112 tag = pci_vpd_srdt_tag(header);
115 if (tag == PCI_VPD_STIN_END) /* End tag descriptor */
116 return off;
118 if ((tag != PCI_VPD_LTIN_ID_STRING) &&
119 (tag != PCI_VPD_LTIN_RO_DATA) &&
120 (tag != PCI_VPD_LTIN_RW_DATA)) {
121 pci_warn(dev, "invalid %s VPD tag %02x at offset %zu",
122 (header[0] & PCI_VPD_LRDT) ? "large" : "short",
123 tag, off);
124 return 0;
127 return 0;
131 * Wait for last operation to complete.
132 * This code has to spin since there is no other notification from the PCI
133 * hardware. Since the VPD is often implemented by serial attachment to an
134 * EEPROM, it may take many milliseconds to complete.
136 * Returns 0 on success, negative values indicate error.
138 static int pci_vpd_wait(struct pci_dev *dev)
140 struct pci_vpd *vpd = dev->vpd;
141 unsigned long timeout = jiffies + msecs_to_jiffies(125);
142 unsigned long max_sleep = 16;
143 u16 status;
144 int ret;
146 if (!vpd->busy)
147 return 0;
149 do {
150 ret = pci_user_read_config_word(dev, vpd->cap + PCI_VPD_ADDR,
151 &status);
152 if (ret < 0)
153 return ret;
155 if ((status & PCI_VPD_ADDR_F) == vpd->flag) {
156 vpd->busy = 0;
157 return 0;
160 if (fatal_signal_pending(current))
161 return -EINTR;
163 if (time_after(jiffies, timeout))
164 break;
166 usleep_range(10, max_sleep);
167 if (max_sleep < 1024)
168 max_sleep *= 2;
169 } while (true);
171 pci_warn(dev, "VPD access failed. This is likely a firmware bug on this device. Contact the card vendor for a firmware update\n");
172 return -ETIMEDOUT;
175 static ssize_t pci_vpd_read(struct pci_dev *dev, loff_t pos, size_t count,
176 void *arg)
178 struct pci_vpd *vpd = dev->vpd;
179 int ret;
180 loff_t end = pos + count;
181 u8 *buf = arg;
183 if (pos < 0)
184 return -EINVAL;
186 if (!vpd->valid) {
187 vpd->valid = 1;
188 vpd->len = pci_vpd_size(dev, vpd->len);
191 if (vpd->len == 0)
192 return -EIO;
194 if (pos > vpd->len)
195 return 0;
197 if (end > vpd->len) {
198 end = vpd->len;
199 count = end - pos;
202 if (mutex_lock_killable(&vpd->lock))
203 return -EINTR;
205 ret = pci_vpd_wait(dev);
206 if (ret < 0)
207 goto out;
209 while (pos < end) {
210 u32 val;
211 unsigned int i, skip;
213 ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
214 pos & ~3);
215 if (ret < 0)
216 break;
217 vpd->busy = 1;
218 vpd->flag = PCI_VPD_ADDR_F;
219 ret = pci_vpd_wait(dev);
220 if (ret < 0)
221 break;
223 ret = pci_user_read_config_dword(dev, vpd->cap + PCI_VPD_DATA, &val);
224 if (ret < 0)
225 break;
227 skip = pos & 3;
228 for (i = 0; i < sizeof(u32); i++) {
229 if (i >= skip) {
230 *buf++ = val;
231 if (++pos == end)
232 break;
234 val >>= 8;
237 out:
238 mutex_unlock(&vpd->lock);
239 return ret ? ret : count;
242 static ssize_t pci_vpd_write(struct pci_dev *dev, loff_t pos, size_t count,
243 const void *arg)
245 struct pci_vpd *vpd = dev->vpd;
246 const u8 *buf = arg;
247 loff_t end = pos + count;
248 int ret = 0;
250 if (pos < 0 || (pos & 3) || (count & 3))
251 return -EINVAL;
253 if (!vpd->valid) {
254 vpd->valid = 1;
255 vpd->len = pci_vpd_size(dev, vpd->len);
258 if (vpd->len == 0)
259 return -EIO;
261 if (end > vpd->len)
262 return -EINVAL;
264 if (mutex_lock_killable(&vpd->lock))
265 return -EINTR;
267 ret = pci_vpd_wait(dev);
268 if (ret < 0)
269 goto out;
271 while (pos < end) {
272 u32 val;
274 val = *buf++;
275 val |= *buf++ << 8;
276 val |= *buf++ << 16;
277 val |= *buf++ << 24;
279 ret = pci_user_write_config_dword(dev, vpd->cap + PCI_VPD_DATA, val);
280 if (ret < 0)
281 break;
282 ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
283 pos | PCI_VPD_ADDR_F);
284 if (ret < 0)
285 break;
287 vpd->busy = 1;
288 vpd->flag = 0;
289 ret = pci_vpd_wait(dev);
290 if (ret < 0)
291 break;
293 pos += sizeof(u32);
295 out:
296 mutex_unlock(&vpd->lock);
297 return ret ? ret : count;
300 static int pci_vpd_set_size(struct pci_dev *dev, size_t len)
302 struct pci_vpd *vpd = dev->vpd;
304 if (len == 0 || len > PCI_VPD_MAX_SIZE)
305 return -EIO;
307 vpd->valid = 1;
308 vpd->len = len;
310 return 0;
313 static const struct pci_vpd_ops pci_vpd_ops = {
314 .read = pci_vpd_read,
315 .write = pci_vpd_write,
316 .set_size = pci_vpd_set_size,
319 static ssize_t pci_vpd_f0_read(struct pci_dev *dev, loff_t pos, size_t count,
320 void *arg)
322 struct pci_dev *tdev = pci_get_slot(dev->bus,
323 PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
324 ssize_t ret;
326 if (!tdev)
327 return -ENODEV;
329 ret = pci_read_vpd(tdev, pos, count, arg);
330 pci_dev_put(tdev);
331 return ret;
334 static ssize_t pci_vpd_f0_write(struct pci_dev *dev, loff_t pos, size_t count,
335 const void *arg)
337 struct pci_dev *tdev = pci_get_slot(dev->bus,
338 PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
339 ssize_t ret;
341 if (!tdev)
342 return -ENODEV;
344 ret = pci_write_vpd(tdev, pos, count, arg);
345 pci_dev_put(tdev);
346 return ret;
349 static int pci_vpd_f0_set_size(struct pci_dev *dev, size_t len)
351 struct pci_dev *tdev = pci_get_slot(dev->bus,
352 PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
353 int ret;
355 if (!tdev)
356 return -ENODEV;
358 ret = pci_set_vpd_size(tdev, len);
359 pci_dev_put(tdev);
360 return ret;
363 static const struct pci_vpd_ops pci_vpd_f0_ops = {
364 .read = pci_vpd_f0_read,
365 .write = pci_vpd_f0_write,
366 .set_size = pci_vpd_f0_set_size,
369 int pci_vpd_init(struct pci_dev *dev)
371 struct pci_vpd *vpd;
372 u8 cap;
374 cap = pci_find_capability(dev, PCI_CAP_ID_VPD);
375 if (!cap)
376 return -ENODEV;
378 vpd = kzalloc(sizeof(*vpd), GFP_ATOMIC);
379 if (!vpd)
380 return -ENOMEM;
382 vpd->len = PCI_VPD_MAX_SIZE;
383 if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0)
384 vpd->ops = &pci_vpd_f0_ops;
385 else
386 vpd->ops = &pci_vpd_ops;
387 mutex_init(&vpd->lock);
388 vpd->cap = cap;
389 vpd->busy = 0;
390 vpd->valid = 0;
391 dev->vpd = vpd;
392 return 0;
395 void pci_vpd_release(struct pci_dev *dev)
397 kfree(dev->vpd);
400 static ssize_t read_vpd_attr(struct file *filp, struct kobject *kobj,
401 struct bin_attribute *bin_attr, char *buf,
402 loff_t off, size_t count)
404 struct pci_dev *dev = to_pci_dev(kobj_to_dev(kobj));
406 if (bin_attr->size > 0) {
407 if (off > bin_attr->size)
408 count = 0;
409 else if (count > bin_attr->size - off)
410 count = bin_attr->size - off;
413 return pci_read_vpd(dev, off, count, buf);
416 static ssize_t write_vpd_attr(struct file *filp, struct kobject *kobj,
417 struct bin_attribute *bin_attr, char *buf,
418 loff_t off, size_t count)
420 struct pci_dev *dev = to_pci_dev(kobj_to_dev(kobj));
422 if (bin_attr->size > 0) {
423 if (off > bin_attr->size)
424 count = 0;
425 else if (count > bin_attr->size - off)
426 count = bin_attr->size - off;
429 return pci_write_vpd(dev, off, count, buf);
432 void pcie_vpd_create_sysfs_dev_files(struct pci_dev *dev)
434 int retval;
435 struct bin_attribute *attr;
437 if (!dev->vpd)
438 return;
440 attr = kzalloc(sizeof(*attr), GFP_ATOMIC);
441 if (!attr)
442 return;
444 sysfs_bin_attr_init(attr);
445 attr->size = 0;
446 attr->attr.name = "vpd";
447 attr->attr.mode = S_IRUSR | S_IWUSR;
448 attr->read = read_vpd_attr;
449 attr->write = write_vpd_attr;
450 retval = sysfs_create_bin_file(&dev->dev.kobj, attr);
451 if (retval) {
452 kfree(attr);
453 return;
456 dev->vpd->attr = attr;
459 void pcie_vpd_remove_sysfs_dev_files(struct pci_dev *dev)
461 if (dev->vpd && dev->vpd->attr) {
462 sysfs_remove_bin_file(&dev->dev.kobj, dev->vpd->attr);
463 kfree(dev->vpd->attr);
467 int pci_vpd_find_tag(const u8 *buf, unsigned int off, unsigned int len, u8 rdt)
469 int i;
471 for (i = off; i < len; ) {
472 u8 val = buf[i];
474 if (val & PCI_VPD_LRDT) {
475 /* Don't return success of the tag isn't complete */
476 if (i + PCI_VPD_LRDT_TAG_SIZE > len)
477 break;
479 if (val == rdt)
480 return i;
482 i += PCI_VPD_LRDT_TAG_SIZE +
483 pci_vpd_lrdt_size(&buf[i]);
484 } else {
485 u8 tag = val & ~PCI_VPD_SRDT_LEN_MASK;
487 if (tag == rdt)
488 return i;
490 if (tag == PCI_VPD_SRDT_END)
491 break;
493 i += PCI_VPD_SRDT_TAG_SIZE +
494 pci_vpd_srdt_size(&buf[i]);
498 return -ENOENT;
500 EXPORT_SYMBOL_GPL(pci_vpd_find_tag);
502 int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off,
503 unsigned int len, const char *kw)
505 int i;
507 for (i = off; i + PCI_VPD_INFO_FLD_HDR_SIZE <= off + len;) {
508 if (buf[i + 0] == kw[0] &&
509 buf[i + 1] == kw[1])
510 return i;
512 i += PCI_VPD_INFO_FLD_HDR_SIZE +
513 pci_vpd_info_field_size(&buf[i]);
516 return -ENOENT;
518 EXPORT_SYMBOL_GPL(pci_vpd_find_info_keyword);
520 #ifdef CONFIG_PCI_QUIRKS
522 * Quirk non-zero PCI functions to route VPD access through function 0 for
523 * devices that share VPD resources between functions. The functions are
524 * expected to be identical devices.
526 static void quirk_f0_vpd_link(struct pci_dev *dev)
528 struct pci_dev *f0;
530 if (!PCI_FUNC(dev->devfn))
531 return;
533 f0 = pci_get_slot(dev->bus, PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
534 if (!f0)
535 return;
537 if (f0->vpd && dev->class == f0->class &&
538 dev->vendor == f0->vendor && dev->device == f0->device)
539 dev->dev_flags |= PCI_DEV_FLAGS_VPD_REF_F0;
541 pci_dev_put(f0);
543 DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_INTEL, PCI_ANY_ID,
544 PCI_CLASS_NETWORK_ETHERNET, 8, quirk_f0_vpd_link);
547 * If a device follows the VPD format spec, the PCI core will not read or
548 * write past the VPD End Tag. But some vendors do not follow the VPD
549 * format spec, so we can't tell how much data is safe to access. Devices
550 * may behave unpredictably if we access too much. Blacklist these devices
551 * so we don't touch VPD at all.
553 static void quirk_blacklist_vpd(struct pci_dev *dev)
555 if (dev->vpd) {
556 dev->vpd->len = 0;
557 pci_warn(dev, FW_BUG "disabling VPD access (can't determine size of non-standard VPD format)\n");
560 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0060, quirk_blacklist_vpd);
561 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x007c, quirk_blacklist_vpd);
562 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0413, quirk_blacklist_vpd);
563 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0078, quirk_blacklist_vpd);
564 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0079, quirk_blacklist_vpd);
565 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0073, quirk_blacklist_vpd);
566 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0071, quirk_blacklist_vpd);
567 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x005b, quirk_blacklist_vpd);
568 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x002f, quirk_blacklist_vpd);
569 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x005d, quirk_blacklist_vpd);
570 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x005f, quirk_blacklist_vpd);
571 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATTANSIC, PCI_ANY_ID,
572 quirk_blacklist_vpd);
573 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_QLOGIC, 0x2261, quirk_blacklist_vpd);
575 * The Amazon Annapurna Labs 0x0031 device id is reused for other non Root Port
576 * device types, so the quirk is registered for the PCI_CLASS_BRIDGE_PCI class.
578 DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_VENDOR_ID_AMAZON_ANNAPURNA_LABS, 0x0031,
579 PCI_CLASS_BRIDGE_PCI, 8, quirk_blacklist_vpd);
582 * For Broadcom 5706, 5708, 5709 rev. A nics, any read beyond the
583 * VPD end tag will hang the device. This problem was initially
584 * observed when a vpd entry was created in sysfs
585 * ('/sys/bus/pci/devices/<id>/vpd'). A read to this sysfs entry
586 * will dump 32k of data. Reading a full 32k will cause an access
587 * beyond the VPD end tag causing the device to hang. Once the device
588 * is hung, the bnx2 driver will not be able to reset the device.
589 * We believe that it is legal to read beyond the end tag and
590 * therefore the solution is to limit the read/write length.
592 static void quirk_brcm_570x_limit_vpd(struct pci_dev *dev)
595 * Only disable the VPD capability for 5706, 5706S, 5708,
596 * 5708S and 5709 rev. A
598 if ((dev->device == PCI_DEVICE_ID_NX2_5706) ||
599 (dev->device == PCI_DEVICE_ID_NX2_5706S) ||
600 (dev->device == PCI_DEVICE_ID_NX2_5708) ||
601 (dev->device == PCI_DEVICE_ID_NX2_5708S) ||
602 ((dev->device == PCI_DEVICE_ID_NX2_5709) &&
603 (dev->revision & 0xf0) == 0x0)) {
604 if (dev->vpd)
605 dev->vpd->len = 0x80;
608 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_BROADCOM,
609 PCI_DEVICE_ID_NX2_5706,
610 quirk_brcm_570x_limit_vpd);
611 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_BROADCOM,
612 PCI_DEVICE_ID_NX2_5706S,
613 quirk_brcm_570x_limit_vpd);
614 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_BROADCOM,
615 PCI_DEVICE_ID_NX2_5708,
616 quirk_brcm_570x_limit_vpd);
617 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_BROADCOM,
618 PCI_DEVICE_ID_NX2_5708S,
619 quirk_brcm_570x_limit_vpd);
620 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_BROADCOM,
621 PCI_DEVICE_ID_NX2_5709,
622 quirk_brcm_570x_limit_vpd);
623 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_BROADCOM,
624 PCI_DEVICE_ID_NX2_5709S,
625 quirk_brcm_570x_limit_vpd);
627 static void quirk_chelsio_extend_vpd(struct pci_dev *dev)
629 int chip = (dev->device & 0xf000) >> 12;
630 int func = (dev->device & 0x0f00) >> 8;
631 int prod = (dev->device & 0x00ff) >> 0;
634 * If this is a T3-based adapter, there's a 1KB VPD area at offset
635 * 0xc00 which contains the preferred VPD values. If this is a T4 or
636 * later based adapter, the special VPD is at offset 0x400 for the
637 * Physical Functions (the SR-IOV Virtual Functions have no VPD
638 * Capabilities). The PCI VPD Access core routines will normally
639 * compute the size of the VPD by parsing the VPD Data Structure at
640 * offset 0x000. This will result in silent failures when attempting
641 * to accesses these other VPD areas which are beyond those computed
642 * limits.
644 if (chip == 0x0 && prod >= 0x20)
645 pci_set_vpd_size(dev, 8192);
646 else if (chip >= 0x4 && func < 0x8)
647 pci_set_vpd_size(dev, 2048);
650 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_CHELSIO, PCI_ANY_ID,
651 quirk_chelsio_extend_vpd);
653 #endif