diff options
Diffstat (limited to 'drivers/pci/pci.c')
| -rw-r--r-- | drivers/pci/pci.c | 112 |
1 files changed, 100 insertions, 12 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 5a14b73cf3a..6bfb942428e 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -68,12 +68,14 @@ pci_max_busnr(void) #endif /* 0 */ -static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn, u8 pos, int cap) +#define PCI_FIND_CAP_TTL 48 + +static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn, + u8 pos, int cap, int *ttl) { u8 id; - int ttl = 48; - while (ttl--) { + while ((*ttl)--) { pci_bus_read_config_byte(bus, devfn, pos, &pos); if (pos < 0x40) break; @@ -89,6 +91,14 @@ static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn, u8 pos, return 0; } +static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn, + u8 pos, int cap) +{ + int ttl = PCI_FIND_CAP_TTL; + + return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl); +} + int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap) { return __pci_find_next_cap(dev->bus, dev->devfn, @@ -96,10 +106,10 @@ int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap) } EXPORT_SYMBOL_GPL(pci_find_next_capability); -static int __pci_bus_find_cap(struct pci_bus *bus, unsigned int devfn, u8 hdr_type, int cap) +static int __pci_bus_find_cap_start(struct pci_bus *bus, + unsigned int devfn, u8 hdr_type) { u16 status; - u8 pos; pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status); if (!(status & PCI_STATUS_CAP_LIST)) @@ -108,15 +118,14 @@ static int __pci_bus_find_cap(struct pci_bus *bus, unsigned int devfn, u8 hdr_ty switch (hdr_type) { case PCI_HEADER_TYPE_NORMAL: case PCI_HEADER_TYPE_BRIDGE: - pos = PCI_CAPABILITY_LIST; - break; + return PCI_CAPABILITY_LIST; case PCI_HEADER_TYPE_CARDBUS: - pos = PCI_CB_CAPABILITY_LIST; - break; + return PCI_CB_CAPABILITY_LIST; default: return 0; } - return __pci_find_next_cap(bus, devfn, pos, cap); + + return 0; } /** @@ -140,7 +149,13 @@ static int __pci_bus_find_cap(struct pci_bus *bus, unsigned int devfn, u8 hdr_ty */ int pci_find_capability(struct pci_dev *dev, int cap) { - return __pci_bus_find_cap(dev->bus, dev->devfn, dev->hdr_type, cap); + int pos; + + pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type); + if (pos) + pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap); + + return pos; } /** @@ -158,11 +173,16 @@ int pci_find_capability(struct pci_dev *dev, int cap) */ int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap) { + int pos; u8 hdr_type; pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type); - return __pci_bus_find_cap(bus, devfn, hdr_type & 0x7f, cap); + pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f); + if (pos) + pos = __pci_find_next_cap(bus, devfn, pos, cap); + + return pos; } /** @@ -214,6 +234,74 @@ int pci_find_ext_capability(struct pci_dev *dev, int cap) } EXPORT_SYMBOL_GPL(pci_find_ext_capability); +static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap) +{ + int rc, ttl = PCI_FIND_CAP_TTL; + u8 cap, mask; + + if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST) + mask = HT_3BIT_CAP_MASK; + else + mask = HT_5BIT_CAP_MASK; + + pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos, + PCI_CAP_ID_HT, &ttl); + while (pos) { + rc = pci_read_config_byte(dev, pos + 3, &cap); + if (rc != PCIBIOS_SUCCESSFUL) + return 0; + + if ((cap & mask) == ht_cap) + return pos; + + pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos, + PCI_CAP_ID_HT, &ttl); + } + + return 0; +} +/** + * pci_find_next_ht_capability - query a device's Hypertransport capabilities + * @dev: PCI device to query + * @pos: Position from which to continue searching + * @ht_cap: Hypertransport capability code + * + * To be used in conjunction with pci_find_ht_capability() to search for + * all capabilities matching @ht_cap. @pos should always be a value returned + * from pci_find_ht_capability(). + * + * NB. To be 100% safe against broken PCI devices, the caller should take + * steps to avoid an infinite loop. + */ +int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap) +{ + return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap); +} +EXPORT_SYMBOL_GPL(pci_find_next_ht_capability); + +/** + * pci_find_ht_capability - query a device's Hypertransport capabilities + * @dev: PCI device to query + * @ht_cap: Hypertransport capability code + * + * Tell if a device supports a given Hypertransport capability. + * Returns an address within the device's PCI configuration space + * or 0 in case the device does not support the request capability. + * The address points to the PCI capability, of type PCI_CAP_ID_HT, + * which has a Hypertransport capability matching @ht_cap. + */ +int pci_find_ht_capability(struct pci_dev *dev, int ht_cap) +{ + int pos; + + pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type); + if (pos) + pos = __pci_find_next_ht_cap(dev, pos, ht_cap); + + return pos; +} +EXPORT_SYMBOL_GPL(pci_find_ht_capability); + /** * pci_find_parent_resource - return resource region of parent bus of given region * @dev: PCI device structure contains resources to be searched |