1 files changed, 5 insertions, 3 deletions

diff --git a/include/asm-x86/acpi.h b/include/asm-x86/acpi.h
index 635d764dc13e..392e17336be1 100644
--- a/include/asm-x86/acpi.h
+++ b/include/asm-x86/acpi.h
@@ -1,5 +1,5 @@
-#ifndef _ASM_X86_ACPI_H
-#define _ASM_X86_ACPI_H
+#ifndef ASM_X86__ACPI_H
+#define ASM_X86__ACPI_H
 
 /*
  *  Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
@@ -140,6 +140,8 @@ static inline unsigned int acpi_processor_cstate_check(unsigned int max_cstate)
             boot_cpu_data.x86_model <= 0x05 &&
             boot_cpu_data.x86_mask < 0x0A)
                 return 1;
+        else if (boot_cpu_has(X86_FEATURE_AMDC1E))
+                return 1;
         else
                 return max_cstate;
 }
@@ -173,4 +175,4 @@ static inline void acpi_fake_nodes(const struct bootnode *fake_nodes,
 
 #define acpi_unlazy_tlb(x)      leave_mm(x)
 
-#endif /*__X86_ASM_ACPI_H*/
+#endif /* ASM_X86__ACPI_H */