x86/PCI: amd: factor out MMCONFIG discovery

This factors out the AMD native MMCONFIG discovery so we can use it
outside amd_bus.c.

amd_bus.c reads AMD MSRs so it can remove the MMCONFIG area from the
PCI resources.  We may also need the MMCONFIG information to work
around BIOS defects in the ACPI MCFG table.

Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: stable@kernel.org       # 2.6.34+
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 11 insertions, 31 deletions

diff --git a/arch/x86/pci/amd_bus.c b/arch/x86/pci/amd_bus.c
index 7b7a89712d50..0567df3890e1 100644
--- a/arch/x86/pci/amd_bus.c
+++ b/arch/x86/pci/amd_bus.c
@@ -30,34 +30,6 @@ static struct pci_hostbridge_probe pci_probes[] __initdata = {
         { 0, 0x18, PCI_VENDOR_ID_AMD, 0x1300 },
 };
 
-static u64 __initdata fam10h_mmconf_start;
-static u64 __initdata fam10h_mmconf_end;
-static void __init get_pci_mmcfg_amd_fam10h_range(void)
-{
-        u32 address;
-        u64 base, msr;
-        unsigned segn_busn_bits;
-
-        /* assume all cpus from fam10h have mmconf */
-        if (boot_cpu_data.x86 < 0x10)
-                return;
-
-        address = MSR_FAM10H_MMIO_CONF_BASE;
-        rdmsrl(address, msr);
-
-        /* mmconfig is not enable */
-        if (!(msr & FAM10H_MMIO_CONF_ENABLE))
-                return;
-
-        base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
-
-        segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
-                         FAM10H_MMIO_CONF_BUSRANGE_MASK;
-
-        fam10h_mmconf_start = base;
-        fam10h_mmconf_end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
-}
-
 #define RANGE_NUM 16
 
 /**
@@ -85,6 +57,9 @@ static int __init early_fill_mp_bus_info(void)
         u64 val;
         u32 address;
         bool found;
+        struct resource fam10h_mmconf_res, *fam10h_mmconf;
+        u64 fam10h_mmconf_start;
+        u64 fam10h_mmconf_end;
 
         if (!early_pci_allowed())
                 return -1;
@@ -211,12 +186,17 @@ static int __init early_fill_mp_bus_info(void)
                 subtract_range(range, RANGE_NUM, 0, end);
 
         /* get mmconfig */
-        get_pci_mmcfg_amd_fam10h_range();
+        fam10h_mmconf = amd_get_mmconfig_range(&fam10h_mmconf_res);
         /* need to take out mmconf range */
-        if (fam10h_mmconf_end) {
-                printk(KERN_DEBUG "Fam 10h mmconf [%llx, %llx]\n", fam10h_mmconf_start, fam10h_mmconf_end);
+        if (fam10h_mmconf) {
+                printk(KERN_DEBUG "Fam 10h mmconf %pR\n", fam10h_mmconf);
+                fam10h_mmconf_start = fam10h_mmconf->start;
+                fam10h_mmconf_end = fam10h_mmconf->end;
                 subtract_range(range, RANGE_NUM, fam10h_mmconf_start,
                                  fam10h_mmconf_end + 1);
+        } else {
+                fam10h_mmconf_start = 0;
+                fam10h_mmconf_end = 0;
         }
 
         /* mmio resource */