fix build bug in "x86: add PCI extended config space access for AMD Barcelona"
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 99221f9..656b40a 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -4,6 +4,7 @@
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/apic.h>
+#include <asm/mmconfig.h>
#include <mach_apic.h>
#include "../setup.h"
diff --git a/include/asm-x86/mmconfig.h b/include/asm-x86/mmconfig.h
index 46d6bb1..691798f 100644
--- a/include/asm-x86/mmconfig.h
+++ b/include/asm-x86/mmconfig.h
@@ -9,6 +9,10 @@
static inline void check_enable_amd_mmconf_dmi(void) { }
#endif
+#if defined(CONFIG_SMP) && defined(CONFIG_X86_64)
extern void __cpuinit amd_enable_pci_ext_cfg(struct cpuinfo_x86 *c);
+#else
+static inline void amd_enable_pci_ext_cfg(struct cpuinfo_x86 *c) { }
+#endif
#endif