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-rw-r--r--arch/avr32/lib/delay.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/arch/avr32/lib/delay.c b/arch/avr32/lib/delay.c
new file mode 100644
index 000000000..c2f4a07dc
--- /dev/null
+++ b/arch/avr32/lib/delay.c
@@ -0,0 +1,57 @@
+/*
+ * Precise Delay Loops for avr32
+ *
+ * Copyright (C) 1993 Linus Torvalds
+ * Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
+ * Copyright (C) 2005-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/timex.h>
+#include <linux/param.h>
+#include <linux/types.h>
+#include <linux/init.h>
+
+#include <asm/processor.h>
+#include <asm/sysreg.h>
+
+int read_current_timer(unsigned long *timer_value)
+{
+ *timer_value = sysreg_read(COUNT);
+ return 0;
+}
+
+void __delay(unsigned long loops)
+{
+ unsigned bclock, now;
+
+ bclock = sysreg_read(COUNT);
+ do {
+ now = sysreg_read(COUNT);
+ } while ((now - bclock) < loops);
+}
+
+inline void __const_udelay(unsigned long xloops)
+{
+ unsigned long long loops;
+
+ asm("mulu.d %0, %1, %2"
+ : "=r"(loops)
+ : "r"(current_cpu_data.loops_per_jiffy * HZ), "r"(xloops));
+ __delay(loops >> 32);
+}
+
+void __udelay(unsigned long usecs)
+{
+ __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
+}
+
+void __ndelay(unsigned long nsecs)
+{
+ __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
+}