+#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/module.h>
+#include <linux/sched.h>
#include <linux/ioport.h>
+#include <linux/wait.h>
+
+#include "pci.h"
/*
* This interrupt-safe spinlock protects all accesses to PCI
EXPORT_SYMBOL(pci_bus_write_config_word);
EXPORT_SYMBOL(pci_bus_write_config_dword);
-static u32 pci_user_cached_config(struct pci_dev *dev, int pos)
+/**
+ * pci_bus_set_ops - Set raw operations of pci bus
+ * @bus: pci bus struct
+ * @ops: new raw operations
+ *
+ * Return previous raw operations
+ */
+struct pci_ops *pci_bus_set_ops(struct pci_bus *bus, struct pci_ops *ops)
+{
+ struct pci_ops *old_ops;
+ unsigned long flags;
+
+ spin_lock_irqsave(&pci_lock, flags);
+ old_ops = bus->ops;
+ bus->ops = ops;
+ spin_unlock_irqrestore(&pci_lock, flags);
+ return old_ops;
+}
+EXPORT_SYMBOL(pci_bus_set_ops);
+
+/**
+ * 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)
{
- u32 data;
+ if (!dev->vpd || !dev->vpd->ops)
+ return -ENODEV;
+ return dev->vpd->ops->read(dev, pos, count, buf);
+}
+EXPORT_SYMBOL(pci_read_vpd);
- data = dev->saved_config_space[pos/sizeof(dev->saved_config_space[0])];
- data >>= (pos % sizeof(dev->saved_config_space[0])) * 8;
- return data;
+/**
+ * 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);
+
+/*
+ * The following routines are to prevent the user from accessing PCI config
+ * space when it's unsafe to do so. Some devices require this during BIST and
+ * we're required to prevent it during D-state transitions.
+ *
+ * We have a bit per device to indicate it's blocked and a global wait queue
+ * for callers to sleep on until devices are unblocked.
+ */
+static DECLARE_WAIT_QUEUE_HEAD(pci_ucfg_wait);
+
+static noinline void pci_wait_ucfg(struct pci_dev *dev)
+{
+ DECLARE_WAITQUEUE(wait, current);
+
+ __add_wait_queue(&pci_ucfg_wait, &wait);
+ do {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ spin_unlock_irq(&pci_lock);
+ schedule();
+ spin_lock_irq(&pci_lock);
+ } while (dev->block_ucfg_access);
+ __remove_wait_queue(&pci_ucfg_wait, &wait);
}
#define PCI_USER_READ_CONFIG(size,type) \
int pci_user_read_config_##size \
(struct pci_dev *dev, int pos, type *val) \
{ \
- unsigned long flags; \
int ret = 0; \
u32 data = -1; \
if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER; \
- spin_lock_irqsave(&pci_lock, flags); \
- if (likely(!dev->block_ucfg_access)) \
- ret = dev->bus->ops->read(dev->bus, dev->devfn, \
+ spin_lock_irq(&pci_lock); \
+ if (unlikely(dev->block_ucfg_access)) pci_wait_ucfg(dev); \
+ ret = dev->bus->ops->read(dev->bus, dev->devfn, \
pos, sizeof(type), &data); \
- else if (pos < sizeof(dev->saved_config_space)) \
- data = pci_user_cached_config(dev, pos); \
- spin_unlock_irqrestore(&pci_lock, flags); \
+ spin_unlock_irq(&pci_lock); \
*val = (type)data; \
return ret; \
}
int pci_user_write_config_##size \
(struct pci_dev *dev, int pos, type val) \
{ \
- unsigned long flags; \
int ret = -EIO; \
if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER; \
- spin_lock_irqsave(&pci_lock, flags); \
- if (likely(!dev->block_ucfg_access)) \
- ret = dev->bus->ops->write(dev->bus, dev->devfn, \
+ spin_lock_irq(&pci_lock); \
+ if (unlikely(dev->block_ucfg_access)) pci_wait_ucfg(dev); \
+ ret = dev->bus->ops->write(dev->bus, dev->devfn, \
pos, sizeof(type), val); \
- spin_unlock_irqrestore(&pci_lock, flags); \
+ spin_unlock_irq(&pci_lock); \
return ret; \
}
PCI_USER_WRITE_CONFIG(word, u16)
PCI_USER_WRITE_CONFIG(dword, u32)
+/* VPD access through PCI 2.2+ VPD capability */
+
+#define PCI_VPD_PCI22_SIZE (PCI_VPD_ADDR_MASK + 1)
+
+struct pci_vpd_pci22 {
+ struct pci_vpd base;
+ struct mutex lock;
+ u16 flag;
+ bool busy;
+ u8 cap;
+};
+
+/*
+ * 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.
+ */
+static int pci_vpd_pci22_wait(struct pci_dev *dev)
+{
+ struct pci_vpd_pci22 *vpd =
+ container_of(dev->vpd, struct pci_vpd_pci22, base);
+ unsigned long timeout = jiffies + HZ/20 + 2;
+ u16 status;
+ int ret;
+
+ if (!vpd->busy)
+ return 0;
+
+ for (;;) {
+ ret = pci_user_read_config_word(dev, vpd->cap + PCI_VPD_ADDR,
+ &status);
+ if (ret)
+ return ret;
+
+ if ((status & PCI_VPD_ADDR_F) == vpd->flag) {
+ vpd->busy = false;
+ return 0;
+ }
+
+ if (time_after(jiffies, timeout))
+ return -ETIMEDOUT;
+ if (fatal_signal_pending(current))
+ return -EINTR;
+ if (!cond_resched())
+ udelay(10);
+ }
+}
+
+static ssize_t pci_vpd_pci22_read(struct pci_dev *dev, loff_t pos, size_t count,
+ void *arg)
+{
+ struct pci_vpd_pci22 *vpd =
+ container_of(dev->vpd, struct pci_vpd_pci22, base);
+ int ret;
+ loff_t end = pos + count;
+ u8 *buf = arg;
+
+ if (pos < 0 || pos > vpd->base.len || end > vpd->base.len)
+ return -EINVAL;
+
+ if (mutex_lock_killable(&vpd->lock))
+ return -EINTR;
+
+ ret = pci_vpd_pci22_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 = true;
+ vpd->flag = PCI_VPD_ADDR_F;
+ ret = pci_vpd_pci22_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_pci22_write(struct pci_dev *dev, loff_t pos, size_t count,
+ const void *arg)
+{
+ struct pci_vpd_pci22 *vpd =
+ container_of(dev->vpd, struct pci_vpd_pci22, base);
+ const u8 *buf = arg;
+ loff_t end = pos + count;
+ int ret = 0;
+
+ if (pos < 0 || (pos & 3) || (count & 3) || end > vpd->base.len)
+ return -EINVAL;
+
+ if (mutex_lock_killable(&vpd->lock))
+ return -EINTR;
+
+ ret = pci_vpd_pci22_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 = true;
+ vpd->flag = 0;
+ ret = pci_vpd_pci22_wait(dev);
+
+ pos += sizeof(u32);
+ }
+out:
+ mutex_unlock(&vpd->lock);
+ return ret ? ret : count;
+}
+
+static void pci_vpd_pci22_release(struct pci_dev *dev)
+{
+ kfree(container_of(dev->vpd, struct pci_vpd_pci22, base));
+}
+
+static const struct pci_vpd_ops pci_vpd_pci22_ops = {
+ .read = pci_vpd_pci22_read,
+ .write = pci_vpd_pci22_write,
+ .release = pci_vpd_pci22_release,
+};
+
+int pci_vpd_pci22_init(struct pci_dev *dev)
+{
+ struct pci_vpd_pci22 *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->base.len = PCI_VPD_PCI22_SIZE;
+ vpd->base.ops = &pci_vpd_pci22_ops;
+ mutex_init(&vpd->lock);
+ vpd->cap = cap;
+ vpd->busy = false;
+ dev->vpd = &vpd->base;
+ return 0;
+}
+
+/**
+ * pci_vpd_truncate - Set available Vital Product Data size
+ * @dev: pci device struct
+ * @size: available memory in bytes
+ *
+ * Adjust size of available VPD area.
+ */
+int pci_vpd_truncate(struct pci_dev *dev, size_t size)
+{
+ if (!dev->vpd)
+ return -EINVAL;
+
+ /* limited by the access method */
+ if (size > dev->vpd->len)
+ return -EINVAL;
+
+ dev->vpd->len = size;
+ if (dev->vpd->attr)
+ dev->vpd->attr->size = size;
+
+ return 0;
+}
+EXPORT_SYMBOL(pci_vpd_truncate);
+
/**
* pci_block_user_cfg_access - Block userspace PCI config reads/writes
* @dev: pci device struct
*
- * This function blocks any userspace PCI config accesses from occurring.
- * When blocked, any writes will be bit bucketed and reads will return the
- * data saved using pci_save_state for the first 64 bytes of config
- * space and return 0xff for all other config reads.
- **/
+ * When user access is blocked, any reads or writes to config space will
+ * sleep until access is unblocked again. We don't allow nesting of
+ * block/unblock calls.
+ */
void pci_block_user_cfg_access(struct pci_dev *dev)
{
unsigned long flags;
+ int was_blocked;
- pci_save_state(dev);
-
- /* spinlock to synchronize with anyone reading config space now */
spin_lock_irqsave(&pci_lock, flags);
+ was_blocked = dev->block_ucfg_access;
dev->block_ucfg_access = 1;
spin_unlock_irqrestore(&pci_lock, flags);
+
+ /* If we BUG() inside the pci_lock, we're guaranteed to hose
+ * the machine */
+ BUG_ON(was_blocked);
}
EXPORT_SYMBOL_GPL(pci_block_user_cfg_access);
* @dev: pci device struct
*
* This function allows userspace PCI config accesses to resume.
- **/
+ */
void pci_unblock_user_cfg_access(struct pci_dev *dev)
{
unsigned long flags;
- /* spinlock to synchronize with anyone reading saved config space */
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. */
+ WARN_ON(!dev->block_ucfg_access);
+
dev->block_ucfg_access = 0;
+ wake_up_all(&pci_ucfg_wait);
spin_unlock_irqrestore(&pci_lock, flags);
}
EXPORT_SYMBOL_GPL(pci_unblock_user_cfg_access);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff