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Diffstat (limited to 'arch/i386/pci/mmconfig.c')
-rw-r--r--arch/i386/pci/mmconfig.c65
1 files changed, 56 insertions, 9 deletions
diff --git a/arch/i386/pci/mmconfig.c b/arch/i386/pci/mmconfig.c
index dfbf80cff834..4bb4d4b0f73a 100644
--- a/arch/i386/pci/mmconfig.c
+++ b/arch/i386/pci/mmconfig.c
@@ -19,21 +19,25 @@
/* The base address of the last MMCONFIG device accessed */
static u32 mmcfg_last_accessed_device;
+static DECLARE_BITMAP(fallback_slots, 32);
+
/*
* Functions for accessing PCI configuration space with MMCONFIG accesses
*/
-static u32 get_base_addr(unsigned int seg, int bus)
+static u32 get_base_addr(unsigned int seg, int bus, unsigned devfn)
{
int cfg_num = -1;
struct acpi_table_mcfg_config *cfg;
+ if (seg == 0 && bus == 0 &&
+ test_bit(PCI_SLOT(devfn), fallback_slots))
+ return 0;
+
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_config[0].base_address;
+ /* Not found - fallback to type 1 */
+ return 0;
}
cfg = &pci_mmcfg_config[cfg_num];
if (cfg->pci_segment_group_number != seg)
@@ -44,9 +48,9 @@ static u32 get_base_addr(unsigned int seg, int bus)
}
}
-static inline void pci_exp_set_dev_base(unsigned int seg, int bus, int devfn)
+static inline void pci_exp_set_dev_base(unsigned int base, int bus, int devfn)
{
- u32 dev_base = get_base_addr(seg, bus) | (bus << 20) | (devfn << 12);
+ u32 dev_base = base | (bus << 20) | (devfn << 12);
if (dev_base != mmcfg_last_accessed_device) {
mmcfg_last_accessed_device = dev_base;
set_fixmap_nocache(FIX_PCIE_MCFG, dev_base);
@@ -57,13 +61,18 @@ static int pci_mmcfg_read(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 *value)
{
unsigned long flags;
+ u32 base;
if (!value || (bus > 255) || (devfn > 255) || (reg > 4095))
return -EINVAL;
+ base = get_base_addr(seg, bus, devfn);
+ if (!base)
+ return pci_conf1_read(seg,bus,devfn,reg,len,value);
+
spin_lock_irqsave(&pci_config_lock, flags);
- pci_exp_set_dev_base(seg, bus, devfn);
+ pci_exp_set_dev_base(base, bus, devfn);
switch (len) {
case 1:
@@ -86,13 +95,18 @@ static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 value)
{
unsigned long flags;
+ u32 base;
if ((bus > 255) || (devfn > 255) || (reg > 4095))
return -EINVAL;
+ base = get_base_addr(seg, bus, devfn);
+ if (!base)
+ return pci_conf1_write(seg,bus,devfn,reg,len,value);
+
spin_lock_irqsave(&pci_config_lock, flags);
- pci_exp_set_dev_base(seg, bus, devfn);
+ pci_exp_set_dev_base(base, bus, devfn);
switch (len) {
case 1:
@@ -116,6 +130,37 @@ static struct pci_raw_ops pci_mmcfg = {
.write = pci_mmcfg_write,
};
+/* 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;
+ unsigned long flags;
+
+ for (i = 0; i < 32; i++) {
+ u32 val1;
+ u32 addr;
+
+ pci_conf1_read(0, 0, PCI_DEVFN(i, 0), 0, 4, &val1);
+ if (val1 == 0xffffffff)
+ continue;
+
+ /* Locking probably not needed, but safer */
+ spin_lock_irqsave(&pci_config_lock, flags);
+ addr = get_base_addr(0, 0, PCI_DEVFN(i, 0));
+ if (addr != 0)
+ pci_exp_set_dev_base(addr, 0, PCI_DEVFN(i, 0));
+ if (addr == 0 || readl((u32 __iomem *)mmcfg_virt_addr) != val1)
+ set_bit(i, fallback_slots);
+ spin_unlock_irqrestore(&pci_config_lock, flags);
+ }
+}
+
static int __init pci_mmcfg_init(void)
{
if ((pci_probe & PCI_PROBE_MMCONF) == 0)
@@ -131,6 +176,8 @@ static int __init pci_mmcfg_init(void)
raw_pci_ops = &pci_mmcfg;
pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
+ unreachable_devices();
+
out:
return 0;
}