x86_64: check MSR to get MMCONFIG for AMD Family 10h

so even booting kernel with acpi=off or even MCFG is not there, we still can
use MMCONFIG.

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Greg KH <greg@kroah.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 69 insertions, 6 deletions

diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index 36a4a7514b0..8707e24e625 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/arch/x86/pci/mmconfig-shared.c
@@ -100,33 +100,96 @@ static const char __init *pci_mmcfg_intel_945(void)
         return "Intel Corporation 945G/GZ/P/PL Express Memory Controller Hub";
 }
 
+static const char __init *pci_mmcfg_amd_fam10h(void)
+{
+        u32 low, high, address;
+        u64 base, msr;
+        int i;
+        unsigned segnbits = 0, busnbits;
+
+        address = MSR_FAM10H_MMIO_CONF_BASE;
+        if (rdmsr_safe(address, &low, &high))
+                return NULL;
+
+        msr = high;
+        msr <<= 32;
+        msr |= low;
+
+        /* mmconfig is not enable */
+        if (!(msr & FAM10H_MMIO_CONF_ENABLE))
+                return NULL;
+
+        base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
+
+        busnbits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
+                         FAM10H_MMIO_CONF_BUSRANGE_MASK;
+
+        /*
+         * only handle bus 0 ?
+         * need to skip it
+         */
+        if (!busnbits)
+                return NULL;
+
+        if (busnbits > 8) {
+                segnbits = busnbits - 8;
+                busnbits = 8;
+        }
+
+        pci_mmcfg_config_num = (1 << segnbits);
+        pci_mmcfg_config = kzalloc(sizeof(pci_mmcfg_config[0]) *
+                                   pci_mmcfg_config_num, GFP_KERNEL);
+        if (!pci_mmcfg_config)
+                return NULL;
+
+        for (i = 0; i < (1 << segnbits); i++) {
+                pci_mmcfg_config[i].address = base + (1<<28) * i;
+                pci_mmcfg_config[i].pci_segment = i;
+                pci_mmcfg_config[i].start_bus_number = 0;
+                pci_mmcfg_config[i].end_bus_number = (1 << busnbits) - 1;
+        }
+
+        return "AMD Family 10h NB";
+}
+
 struct pci_mmcfg_hostbridge_probe {
+        u32 bus;
+        u32 devfn;
         u32 vendor;
         u32 device;
         const char *(*probe)(void);
 };
 
 static struct pci_mmcfg_hostbridge_probe pci_mmcfg_probes[] __initdata = {
-        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_E7520_MCH, pci_mmcfg_e7520 },
-        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82945G_HB, pci_mmcfg_intel_945 },
+        { 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_INTEL,
+          PCI_DEVICE_ID_INTEL_E7520_MCH, pci_mmcfg_e7520 },
+        { 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_INTEL,
+          PCI_DEVICE_ID_INTEL_82945G_HB, pci_mmcfg_intel_945 },
+        { 0, PCI_DEVFN(0x18, 0), PCI_VENDOR_ID_AMD,
+          0x1200, pci_mmcfg_amd_fam10h },
+        { 0xff, PCI_DEVFN(0, 0), PCI_VENDOR_ID_AMD,
+          0x1200, pci_mmcfg_amd_fam10h },
 };
 
 static int __init pci_mmcfg_check_hostbridge(void)
 {
         u32 l;
+        u32 bus, devfn;
         u16 vendor, device;
         int i;
         const char *name;
 
-        pci_direct_conf1.read(0, 0, PCI_DEVFN(0,0), 0, 4, &l);
-        vendor = l & 0xffff;
-        device = (l >> 16) & 0xffff;
-
         pci_mmcfg_config_num = 0;
         pci_mmcfg_config = NULL;
         name = NULL;
 
         for (i = 0; !name && i < ARRAY_SIZE(pci_mmcfg_probes); i++) {
+                bus =  pci_mmcfg_probes[i].bus;
+                devfn = pci_mmcfg_probes[i].devfn;
+                pci_direct_conf1.read(0, bus, devfn, 0, 4, &l);
+                vendor = l & 0xffff;
+                device = (l >> 16) & 0xffff;
+
                 if (pci_mmcfg_probes[i].vendor == vendor &&
                     pci_mmcfg_probes[i].device == device)
                         name = pci_mmcfg_probes[i].probe();