-#ifndef __ASM_X86_PROCESSOR_H
-#define __ASM_X86_PROCESSOR_H
+#ifndef ASM_X86__PROCESSOR_H
+#define ASM_X86__PROCESSOR_H
#include <asm/processor-flags.h>
extern unsigned long idle_halt;
extern unsigned long idle_nomwait;
+/*
+ * on systems with caches, caches must be flashed as the absolute
+ * last instruction before going into a suspended halt. Otherwise,
+ * dirty data can linger in the cache and become stale on resume,
+ * leading to strange errors.
+ *
+ * perform a variety of operations to guarantee that the compiler
+ * will not reorder instructions. wbinvd itself is serializing
+ * so the processor will not reorder.
+ *
+ * Systems without cache can just go into halt.
+ */
+static inline void wbinvd_halt(void)
+{
+ mb();
+ /* check for clflush to determine if wbinvd is legal */
+ if (cpu_has_clflush)
+ asm volatile("cli; wbinvd; 1: hlt; jmp 1b" : : : "memory");
+ else
+ while (1)
+ halt();
+}
+
extern void enable_sep_cpu(void);
extern int sysenter_setup(void);
extern int get_tsc_mode(unsigned long adr);
extern int set_tsc_mode(unsigned int val);
-#endif
+#endif /* ASM_X86__PROCESSOR_H */