static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 value)
{
char __iomem *addr;
/* Why do we have this when nobody checks it. How about a BUG()!? -AK */
if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095)))
return -EINVAL;
addr = pci_dev_base(seg, bus, devfn);
if (!addr)
return pci_conf1_write(seg,bus,devfn,reg,len,value);
switch (len) {
case 1:
writeb(value, addr + reg);
break;
case 2:
writew(value, addr + reg);
break;
case 4:
writel(value, addr + reg);
break;
}
return 0;
}
static int pci_mmcfg_read(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 *value)
{
char __iomem *addr;
/* Why do we have this when nobody checks it. How about a BUG()!? -AK */
if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) {
*value = -1;
return -EINVAL;
}
addr = pci_dev_base(seg, bus, devfn);
if (!addr)
return pci_conf1_read(seg,bus,devfn,reg,len,value);
switch (len) {
case 1:
*value = mmio_config_readb(addr + reg);
break;
case 2:
*value = mmio_config_readw(addr + reg);
break;
case 4:
*value = mmio_config_readl(addr + reg);
break;
}
return 0;
}
static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 value)
{
char __iomem *addr;
/* Why do we have this when nobody checks it. How about a BUG()!? -AK */
if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095)))
return -EINVAL;
rcu_read_lock();
addr = pci_dev_base(seg, bus, devfn);
if (!addr) {
rcu_read_unlock();
return -EINVAL;
}
switch (len) {
case 1:
mmio_config_writeb(addr + reg, value);
break;
case 2:
mmio_config_writew(addr + reg, value);
break;
case 4:
mmio_config_writel(addr + reg, value);
break;
}
rcu_read_unlock();
return 0;
}
/* K8 systems have some devices (typically in the builtin northbridge)
that are only accessible using type1
Normally this can be expressed in the MCFG by not listing them
and assigning suitable _SEGs, but this isn't implemented in some BIOS.
Instead try to discover all devices on bus 0 that are unreachable using MM
and fallback for them.
We only do this for bus 0/seg 0 */
static __init void unreachable_devices(void)
{
int i;
for (i = 0; i < 32; i++) {
u32 val1;
char __iomem *addr;
pci_conf1_read(0, 0, PCI_DEVFN(i,0), 0, 4, &val1);
if (val1 == 0xffffffff)
continue;
addr = pci_dev_base(0, 0, PCI_DEVFN(i, 0));
if (addr == NULL|| readl(addr) != val1) {
set_bit(i, &fallback_slots);
}
}
}
int __init pci_mmcfg_arch_reachable(unsigned int seg, unsigned int bus,
unsigned int devfn)
{
return pci_dev_base(seg, bus, devfn) != NULL;
}