diff options
Diffstat (limited to 'arch/i386/pci/mmconfig.c')
| -rw-r--r-- | arch/i386/pci/mmconfig.c | 65 |
1 files changed, 56 insertions, 9 deletions
diff --git a/arch/i386/pci/mmconfig.c b/arch/i386/pci/mmconfig.c index dfbf80cff834..08a084901212 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 *)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; } |
