1 files changed, 34 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/delay.h b/arch/powerpc/include/asm/delay.h
new file mode 100644
index 000000000000..f9200a65c632
--- /dev/null
+++ b/arch/powerpc/include/asm/delay.h
@@ -0,0 +1,34 @@
+#ifndef _ASM_POWERPC_DELAY_H
+#define _ASM_POWERPC_DELAY_H
+#ifdef __KERNEL__
+
+/*
+ * Copyright 1996, Paul Mackerras.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * PPC64 Support added by Dave Engebretsen, Todd Inglett, Mike Corrigan,
+ * Anton Blanchard.
+ */
+
+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 mdelay(n)       udelay((n) * 1000)
+#endif
+
+#endif /* __KERNEL__ */
+#endif /* _ASM_POWERPC_DELAY_H */