X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=include%2Fasm-powerpc%2Fdelay.h;h=f9200a65c632b9421d02b16106feded2eb3eb4eb;hb=c45c357d7dbc9e94338f44349e0035149da86b26;hp=1492aa9ab716414aa98b17dec31f5840e0a37b02;hpb=4060994c3e337b40e0f6fa8ce2cc178e021baf3d;p=powerpc.git

diff --git a/include/asm-powerpc/delay.h b/include/asm-powerpc/delay.h
index 1492aa9ab7..f9200a65c6 100644
--- a/include/asm-powerpc/delay.h
+++ b/include/asm-powerpc/delay.h
@@ -1,5 +1,6 @@
 #ifndef _ASM_POWERPC_DELAY_H
 #define _ASM_POWERPC_DELAY_H
+#ifdef __KERNEL__
 
 /*
  * Copyright 1996, Paul Mackerras.
@@ -13,43 +14,21 @@
  * Anton Blanchard.
  */
 
-extern unsigned long tb_ticks_per_usec;
+extern void __delay(unsigned long loops);
+extern void udelay(unsigned long usecs);
 
+/*
+ * On shared processor machines the generic implementation of mdelay can
+ * result in large errors. While each iteration of the loop inside mdelay
+ * is supposed to take 1ms, the hypervisor could sleep our partition for
+ * longer (eg 10ms). With the right timing these errors can add up.
+ *
+ * Since there is no 32bit overflow issue on 64bit kernels, just call
+ * udelay directly.
+ */
 #ifdef CONFIG_PPC64
-/* define these here to prevent circular dependencies */
-/* these instructions control the thread priority on multi-threaded cpus */
-#define __HMT_low()	asm volatile("or 1,1,1")
-#define __HMT_medium()	asm volatile("or 2,2,2")
-#else
-#define __HMT_low()
-#define __HMT_medium()
+#define mdelay(n)	udelay((n) * 1000)
 #endif
 
-#define __barrier()	asm volatile("" ::: "memory")
-
-static inline unsigned long __get_tb(void)
-{
-	unsigned long rval;
-
-	asm volatile("mftb %0" : "=r" (rval));
-	return rval;
-}
-
-static inline void __delay(unsigned long loops)
-{
-	unsigned long start = __get_tb();
-
-	while((__get_tb() - start) < loops)
-		__HMT_low();
-	__HMT_medium();
-	__barrier();
-}
-
-static inline void udelay(unsigned long usecs)
-{
-	unsigned long loops = tb_ticks_per_usec * usecs;
-
-	__delay(loops);
-}
-
+#endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_DELAY_H */