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path: root/drivers/pci/vpd.c
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Diffstat (limited to 'drivers/pci/vpd.c')
-rw-r--r--drivers/pci/vpd.c369
1 files changed, 369 insertions, 0 deletions
diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c
index 70fba57d6103..4596452d58bf 100644
--- a/drivers/pci/vpd.c
+++ b/drivers/pci/vpd.c
@@ -7,7 +7,376 @@
*/
#include <linux/pci.h>
+#include <linux/delay.h>
#include <linux/export.h>
+#include <linux/sched/signal.h>
+#include "pci.h"
+
+/* VPD access through PCI 2.2+ VPD capability */
+
+/**
+ * pci_read_vpd - Read one entry from Vital Product Data
+ * @dev: pci device struct
+ * @pos: offset in vpd space
+ * @count: number of bytes to read
+ * @buf: pointer to where to store result
+ */
+ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf)
+{
+ if (!dev->vpd || !dev->vpd->ops)
+ return -ENODEV;
+ return dev->vpd->ops->read(dev, pos, count, buf);
+}
+EXPORT_SYMBOL(pci_read_vpd);
+
+/**
+ * pci_write_vpd - Write entry to Vital Product Data
+ * @dev: pci device struct
+ * @pos: offset in vpd space
+ * @count: number of bytes to write
+ * @buf: buffer containing write data
+ */
+ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const void *buf)
+{
+ if (!dev->vpd || !dev->vpd->ops)
+ return -ENODEV;
+ return dev->vpd->ops->write(dev, pos, count, buf);
+}
+EXPORT_SYMBOL(pci_write_vpd);
+
+/**
+ * pci_set_vpd_size - Set size of Vital Product Data space
+ * @dev: pci device struct
+ * @len: size of vpd space
+ */
+int pci_set_vpd_size(struct pci_dev *dev, size_t len)
+{
+ if (!dev->vpd || !dev->vpd->ops)
+ return -ENODEV;
+ return dev->vpd->ops->set_size(dev, len);
+}
+EXPORT_SYMBOL(pci_set_vpd_size);
+
+#define PCI_VPD_MAX_SIZE (PCI_VPD_ADDR_MASK + 1)
+
+/**
+ * pci_vpd_size - determine actual size of Vital Product Data
+ * @dev: pci device struct
+ * @old_size: current assumed size, also maximum allowed size
+ */
+static size_t pci_vpd_size(struct pci_dev *dev, size_t old_size)
+{
+ size_t off = 0;
+ unsigned char header[1+2]; /* 1 byte tag, 2 bytes length */
+
+ while (off < old_size &&
+ pci_read_vpd(dev, off, 1, header) == 1) {
+ unsigned char tag;
+
+ if (header[0] & PCI_VPD_LRDT) {
+ /* Large Resource Data Type Tag */
+ tag = pci_vpd_lrdt_tag(header);
+ /* Only read length from known tag items */
+ if ((tag == PCI_VPD_LTIN_ID_STRING) ||
+ (tag == PCI_VPD_LTIN_RO_DATA) ||
+ (tag == PCI_VPD_LTIN_RW_DATA)) {
+ if (pci_read_vpd(dev, off+1, 2,
+ &header[1]) != 2) {
+ pci_warn(dev, "invalid large VPD tag %02x size at offset %zu",
+ tag, off + 1);
+ return 0;
+ }
+ off += PCI_VPD_LRDT_TAG_SIZE +
+ pci_vpd_lrdt_size(header);
+ }
+ } else {
+ /* Short Resource Data Type Tag */
+ off += PCI_VPD_SRDT_TAG_SIZE +
+ pci_vpd_srdt_size(header);
+ tag = pci_vpd_srdt_tag(header);
+ }
+
+ if (tag == PCI_VPD_STIN_END) /* End tag descriptor */
+ return off;
+
+ if ((tag != PCI_VPD_LTIN_ID_STRING) &&
+ (tag != PCI_VPD_LTIN_RO_DATA) &&
+ (tag != PCI_VPD_LTIN_RW_DATA)) {
+ pci_warn(dev, "invalid %s VPD tag %02x at offset %zu",
+ (header[0] & PCI_VPD_LRDT) ? "large" : "short",
+ tag, off);
+ return 0;
+ }
+ }
+ return 0;
+}
+
+/*
+ * Wait for last operation to complete.
+ * This code has to spin since there is no other notification from the PCI
+ * hardware. Since the VPD is often implemented by serial attachment to an
+ * EEPROM, it may take many milliseconds to complete.
+ *
+ * Returns 0 on success, negative values indicate error.
+ */
+static int pci_vpd_wait(struct pci_dev *dev)
+{
+ struct pci_vpd *vpd = dev->vpd;
+ unsigned long timeout = jiffies + msecs_to_jiffies(125);
+ unsigned long max_sleep = 16;
+ u16 status;
+ int ret;
+
+ if (!vpd->busy)
+ return 0;
+
+ while (time_before(jiffies, timeout)) {
+ ret = pci_user_read_config_word(dev, vpd->cap + PCI_VPD_ADDR,
+ &status);
+ if (ret < 0)
+ return ret;
+
+ if ((status & PCI_VPD_ADDR_F) == vpd->flag) {
+ vpd->busy = 0;
+ return 0;
+ }
+
+ if (fatal_signal_pending(current))
+ return -EINTR;
+
+ usleep_range(10, max_sleep);
+ if (max_sleep < 1024)
+ max_sleep *= 2;
+ }
+
+ pci_warn(dev, "VPD access failed. This is likely a firmware bug on this device. Contact the card vendor for a firmware update\n");
+ return -ETIMEDOUT;
+}
+
+static ssize_t pci_vpd_read(struct pci_dev *dev, loff_t pos, size_t count,
+ void *arg)
+{
+ struct pci_vpd *vpd = dev->vpd;
+ int ret;
+ loff_t end = pos + count;
+ u8 *buf = arg;
+
+ if (pos < 0)
+ return -EINVAL;
+
+ if (!vpd->valid) {
+ vpd->valid = 1;
+ vpd->len = pci_vpd_size(dev, vpd->len);
+ }
+
+ if (vpd->len == 0)
+ return -EIO;
+
+ if (pos > vpd->len)
+ return 0;
+
+ if (end > vpd->len) {
+ end = vpd->len;
+ count = end - pos;
+ }
+
+ if (mutex_lock_killable(&vpd->lock))
+ return -EINTR;
+
+ ret = pci_vpd_wait(dev);
+ if (ret < 0)
+ goto out;
+
+ while (pos < end) {
+ u32 val;
+ unsigned int i, skip;
+
+ ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
+ pos & ~3);
+ if (ret < 0)
+ break;
+ vpd->busy = 1;
+ vpd->flag = PCI_VPD_ADDR_F;
+ ret = pci_vpd_wait(dev);
+ if (ret < 0)
+ break;
+
+ ret = pci_user_read_config_dword(dev, vpd->cap + PCI_VPD_DATA, &val);
+ if (ret < 0)
+ break;
+
+ skip = pos & 3;
+ for (i = 0; i < sizeof(u32); i++) {
+ if (i >= skip) {
+ *buf++ = val;
+ if (++pos == end)
+ break;
+ }
+ val >>= 8;
+ }
+ }
+out:
+ mutex_unlock(&vpd->lock);
+ return ret ? ret : count;
+}
+
+static ssize_t pci_vpd_write(struct pci_dev *dev, loff_t pos, size_t count,
+ const void *arg)
+{
+ struct pci_vpd *vpd = dev->vpd;
+ const u8 *buf = arg;
+ loff_t end = pos + count;
+ int ret = 0;
+
+ if (pos < 0 || (pos & 3) || (count & 3))
+ return -EINVAL;
+
+ if (!vpd->valid) {
+ vpd->valid = 1;
+ vpd->len = pci_vpd_size(dev, vpd->len);
+ }
+
+ if (vpd->len == 0)
+ return -EIO;
+
+ if (end > vpd->len)
+ return -EINVAL;
+
+ if (mutex_lock_killable(&vpd->lock))
+ return -EINTR;
+
+ ret = pci_vpd_wait(dev);
+ if (ret < 0)
+ goto out;
+
+ while (pos < end) {
+ u32 val;
+
+ val = *buf++;
+ val |= *buf++ << 8;
+ val |= *buf++ << 16;
+ val |= *buf++ << 24;
+
+ ret = pci_user_write_config_dword(dev, vpd->cap + PCI_VPD_DATA, val);
+ if (ret < 0)
+ break;
+ ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
+ pos | PCI_VPD_ADDR_F);
+ if (ret < 0)
+ break;
+
+ vpd->busy = 1;
+ vpd->flag = 0;
+ ret = pci_vpd_wait(dev);
+ if (ret < 0)
+ break;
+
+ pos += sizeof(u32);
+ }
+out:
+ mutex_unlock(&vpd->lock);
+ return ret ? ret : count;
+}
+
+static int pci_vpd_set_size(struct pci_dev *dev, size_t len)
+{
+ struct pci_vpd *vpd = dev->vpd;
+
+ if (len == 0 || len > PCI_VPD_MAX_SIZE)
+ return -EIO;
+
+ vpd->valid = 1;
+ vpd->len = len;
+
+ return 0;
+}
+
+static const struct pci_vpd_ops pci_vpd_ops = {
+ .read = pci_vpd_read,
+ .write = pci_vpd_write,
+ .set_size = pci_vpd_set_size,
+};
+
+static ssize_t pci_vpd_f0_read(struct pci_dev *dev, loff_t pos, size_t count,
+ void *arg)
+{
+ struct pci_dev *tdev = pci_get_slot(dev->bus,
+ PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
+ ssize_t ret;
+
+ if (!tdev)
+ return -ENODEV;
+
+ ret = pci_read_vpd(tdev, pos, count, arg);
+ pci_dev_put(tdev);
+ return ret;
+}
+
+static ssize_t pci_vpd_f0_write(struct pci_dev *dev, loff_t pos, size_t count,
+ const void *arg)
+{
+ struct pci_dev *tdev = pci_get_slot(dev->bus,
+ PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
+ ssize_t ret;
+
+ if (!tdev)
+ return -ENODEV;
+
+ ret = pci_write_vpd(tdev, pos, count, arg);
+ pci_dev_put(tdev);
+ return ret;
+}
+
+static int pci_vpd_f0_set_size(struct pci_dev *dev, size_t len)
+{
+ struct pci_dev *tdev = pci_get_slot(dev->bus,
+ PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
+ int ret;
+
+ if (!tdev)
+ return -ENODEV;
+
+ ret = pci_set_vpd_size(tdev, len);
+ pci_dev_put(tdev);
+ return ret;
+}
+
+static const struct pci_vpd_ops pci_vpd_f0_ops = {
+ .read = pci_vpd_f0_read,
+ .write = pci_vpd_f0_write,
+ .set_size = pci_vpd_f0_set_size,
+};
+
+int pci_vpd_init(struct pci_dev *dev)
+{
+ struct pci_vpd *vpd;
+ u8 cap;
+
+ cap = pci_find_capability(dev, PCI_CAP_ID_VPD);
+ if (!cap)
+ return -ENODEV;
+
+ vpd = kzalloc(sizeof(*vpd), GFP_ATOMIC);
+ if (!vpd)
+ return -ENOMEM;
+
+ vpd->len = PCI_VPD_MAX_SIZE;
+ if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0)
+ vpd->ops = &pci_vpd_f0_ops;
+ else
+ vpd->ops = &pci_vpd_ops;
+ mutex_init(&vpd->lock);
+ vpd->cap = cap;
+ vpd->busy = 0;
+ vpd->valid = 0;
+ dev->vpd = vpd;
+ return 0;
+}
+
+void pci_vpd_release(struct pci_dev *dev)
+{
+ kfree(dev->vpd);
+}
int pci_vpd_find_tag(const u8 *buf, unsigned int off, unsigned int len, u8 rdt)
{
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-18 21:25:22 +0300