diff options
Diffstat (limited to 'drivers/pci/access.c')
-rw-r--r-- | drivers/pci/access.c | 380 |
1 files changed, 7 insertions, 373 deletions
diff --git a/drivers/pci/access.c b/drivers/pci/access.c index 5e9a9822d9d4..a3ad2fe185b9 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 -#include <linux/delay.h> #include <linux/pci.h> #include <linux/module.h> -#include <linux/sched/signal.h> #include <linux/slab.h> #include <linux/ioport.h> #include <linux/wait.h> @@ -17,9 +15,9 @@ DEFINE_RAW_SPINLOCK(pci_lock); /* - * Wrappers for all PCI configuration access functions. They just check - * alignment, do locking and call the low-level functions pointed to - * by pci_dev->ops. + * Wrappers for all PCI configuration access functions. They just check + * alignment, do locking and call the low-level functions pointed to + * by pci_dev->ops. */ #define PCI_byte_BAD 0 @@ -264,372 +262,6 @@ PCI_USER_WRITE_CONFIG(byte, u8) PCI_USER_WRITE_CONFIG(word, u16) PCI_USER_WRITE_CONFIG(dword, u32) -/* 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); -} - /** * pci_cfg_access_lock - Lock PCI config reads/writes * @dev: pci device struct @@ -686,8 +318,10 @@ void pci_cfg_access_unlock(struct pci_dev *dev) raw_spin_lock_irqsave(&pci_lock, flags); - /* This indicates a problem in the caller, but we don't need - * to kill them, unlike a double-block above. */ + /* + * This indicates a problem in the caller, but we don't need + * to kill them, unlike a double-block above. + */ WARN_ON(!dev->block_cfg_access); dev->block_cfg_access = 0; |