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Diffstat (limited to 'arch/x86_64/pci/mmconfig.c')
-rw-r--r--arch/x86_64/pci/mmconfig.c29
1 files changed, 20 insertions, 9 deletions
diff --git a/arch/x86_64/pci/mmconfig.c b/arch/x86_64/pci/mmconfig.c
index a0838c4a94e4..22ff1b07d4e0 100644
--- a/arch/x86_64/pci/mmconfig.c
+++ b/arch/x86_64/pci/mmconfig.c
@@ -19,7 +19,7 @@ struct mmcfg_virt {
};
static struct mmcfg_virt *pci_mmcfg_virt;
-static char *get_virt(unsigned int seg, int bus)
+static char *get_virt(unsigned int seg, unsigned bus)
{
int cfg_num = -1;
struct acpi_table_mcfg_config *cfg;
@@ -27,10 +27,9 @@ static char *get_virt(unsigned int seg, int bus)
while (1) {
++cfg_num;
if (cfg_num >= pci_mmcfg_config_num) {
- /* something bad is going on, no cfg table is found. */
- /* so we fall back to the old way we used to do this */
- /* and just rely on the first entry to be correct. */
- return pci_mmcfg_virt[0].virt;
+ /* Not found - fall back to type 1. This happens
+ e.g. on the internal devices of a K8 northbridge. */
+ return NULL;
}
cfg = pci_mmcfg_virt[cfg_num].cfg;
if (cfg->pci_segment_group_number != seg)
@@ -43,18 +42,25 @@ static char *get_virt(unsigned int seg, int bus)
static inline char *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn)
{
-
- return get_virt(seg, bus) + ((bus << 20) | (devfn << 12));
+ char *addr = get_virt(seg, bus);
+ if (!addr)
+ return NULL;
+ return addr + ((bus << 20) | (devfn << 12));
}
static int pci_mmcfg_read(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 *value)
{
- char *addr = pci_dev_base(seg, bus, devfn);
+ char *addr;
+ /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
if (unlikely(!value || (bus > 255) || (devfn > 255) || (reg > 4095)))
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 = readb(addr + reg);
@@ -73,11 +79,16 @@ static int pci_mmcfg_read(unsigned int seg, unsigned int bus,
static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 value)
{
- char *addr = pci_dev_base(seg, bus, devfn);
+ char *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);