int xen_host_pci_find_ext_cap_offset(XenHostPCIDevice *d, uint32_t cap)
{
uint32_t header = 0;
int max_cap = XEN_HOST_PCI_MAX_EXT_CAP;
int pos = PCI_CONFIG_SPACE_SIZE;
do {
if (xen_host_pci_get_long(d, pos, &header)) {
break;
}
/*
* If we have no capabilities, this is indicated by cap ID,
* cap version and next pointer all being 0.
*/
if (header == 0) {
break;
}
if (PCI_EXT_CAP_ID(header) == cap) {
return pos;
}
pos = PCI_EXT_CAP_NEXT(header);
if (pos < PCI_CONFIG_SPACE_SIZE) {
break;
}
max_cap--;
} while (max_cap > 0);
return -1;
}
static uint16_t pcie_find_capability_list(PCIDevice *dev, uint16_t cap_id,
uint16_t *prev_p)
{
uint16_t prev = 0;
uint16_t next;
uint32_t header = pci_get_long(dev->config + PCI_CONFIG_SPACE_SIZE);
if (!header) {
/* no extended capability */
next = 0;
goto out;
}
for (next = PCI_CONFIG_SPACE_SIZE; next;
prev = next, next = PCI_EXT_CAP_NEXT(header)) {
assert(next >= PCI_CONFIG_SPACE_SIZE);
assert(next <= PCIE_CONFIG_SPACE_SIZE - 8);
header = pci_get_long(dev->config + next);
if (PCI_EXT_CAP_ID(header) == cap_id) {
break;
}
}
out:
if (prev_p) {
*prev_p = prev;
}
return next;
}
/*
* caller must supply valid (offset, size) * such that the range shouldn't
* overlap with other capability or other registers.
* This function doesn't check it.
*/
void pcie_add_capability(PCIDevice *dev,
uint16_t cap_id, uint8_t cap_ver,
uint16_t offset, uint16_t size)
{
uint32_t header;
uint16_t next;
assert(offset >= PCI_CONFIG_SPACE_SIZE);
assert(offset < offset + size);
assert(offset + size < PCIE_CONFIG_SPACE_SIZE);
assert(size >= 8);
assert(pci_is_express(dev));
if (offset == PCI_CONFIG_SPACE_SIZE) {
header = pci_get_long(dev->config + offset);
next = PCI_EXT_CAP_NEXT(header);
} else {
uint16_t prev;
/* 0 is reserved cap id. use internally to find the last capability
in the linked list */
next = pcie_find_capability_list(dev, 0, &prev);
assert(prev >= PCI_CONFIG_SPACE_SIZE);
assert(next == 0);
pcie_ext_cap_set_next(dev, prev, offset);
}
pci_set_long(dev->config + offset, PCI_EXT_CAP(cap_id, cap_ver, next));
/* Make capability read-only by default */
memset(dev->wmask + offset, 0, size);
memset(dev->w1cmask + offset, 0, size);
/* Check capability by default */
memset(dev->cmask + offset, 0xFF, size);
}
/**
* fixed_bar_cap - return the offset of the fixed BAR cap if found
* @bus: PCI bus
* @devfn: device in question
*
* Look for the fixed BAR cap on @bus and @devfn, returning its offset
* if found or 0 otherwise.
*/
static int fixed_bar_cap(struct pci_bus *bus, unsigned int devfn)
{
int pos;
u32 pcie_cap = 0, cap_data;
pos = PCIE_CAP_OFFSET;
if (!raw_pci_ext_ops)
return 0;
while (pos) {
if (raw_pci_ext_ops->read(pci_domain_nr(bus), bus->number,
devfn, pos, 4, &pcie_cap))
return 0;
if (PCI_EXT_CAP_ID(pcie_cap) == 0x0000 ||
PCI_EXT_CAP_ID(pcie_cap) == 0xffff)
break;
if (PCI_EXT_CAP_ID(pcie_cap) == PCI_EXT_CAP_ID_VNDR) {
raw_pci_ext_ops->read(pci_domain_nr(bus), bus->number,
devfn, pos + 4, 4, &cap_data);
if ((cap_data & 0xffff) == PCIE_VNDR_CAP_ID_FIXED_BAR)
return pos;
}
pos = PCI_EXT_CAP_NEXT(pcie_cap);
}
return 0;
}
