4 files changed, 18 insertions, 4 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index eb4092568f9e..ddb52b8d38a7 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -627,7 +627,7 @@ config GART_IOMMU
         bool "GART IOMMU support" if EMBEDDED
         default y
         select SWIOTLB
-        depends on X86_64 && PCI
+        depends on X86_64 && PCI && K8_NB
         ---help---
           Support for full DMA access of devices with 32bit memory access only
           on systems with more than 3GB. This is usually needed for USB,
@@ -2026,7 +2026,7 @@ endif # X86_32
 
 config K8_NB
         def_bool y
-        depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
+        depends on CPU_SUP_AMD && PCI
 
 source "drivers/pcmcia/Kconfig"
 
diff --git a/arch/x86/kernel/k8.c b/arch/x86/kernel/k8.c
index cbc4332a77b2..9b895464dd03 100644
--- a/arch/x86/kernel/k8.c
+++ b/arch/x86/kernel/k8.c
@@ -121,3 +121,17 @@ void k8_flush_garts(void)
 }
 EXPORT_SYMBOL_GPL(k8_flush_garts);
 
+static __init int init_k8_nbs(void)
+{
+        int err = 0;
+
+        err = cache_k8_northbridges();
+
+        if (err < 0)
+                printk(KERN_NOTICE "K8 NB: Cannot enumerate AMD northbridges.\n");
+
+        return err;
+}
+
+/* This has to go after the PCI subsystem */
+fs_initcall(init_k8_nbs);
diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c
index 34de53b46f87..f3af115a573a 100644
--- a/arch/x86/kernel/pci-gart_64.c
+++ b/arch/x86/kernel/pci-gart_64.c
@@ -735,7 +735,7 @@ int __init gart_iommu_init(void)
         unsigned long scratch;
         long i;
 
-        if (cache_k8_northbridges() < 0 || num_k8_northbridges == 0)
+        if (num_k8_northbridges == 0)
                 return 0;
 
 #ifndef CONFIG_AGP_AMD64
diff --git a/drivers/char/agp/Kconfig b/drivers/char/agp/Kconfig
index 2fb3a480f6b0..4b66c69eaf57 100644
--- a/drivers/char/agp/Kconfig
+++ b/drivers/char/agp/Kconfig
@@ -57,7 +57,7 @@ config AGP_AMD
 
 config AGP_AMD64
         tristate "AMD Opteron/Athlon64 on-CPU GART support"
-        depends on AGP && X86
+        depends on AGP && X86 && K8_NB
         help
           This option gives you AGP support for the GLX component of
           X using the on-CPU northbridge of the AMD Athlon64/Opteron CPUs.