1 files changed, 75 insertions, 0 deletions
diff --git a/kernel/arch/xtensa/include/asm/delay.h b/kernel/arch/xtensa/include/asm/delay.h
new file mode 100644
index 000000000..24304b39a
--- /dev/null
+++ b/kernel/arch/xtensa/include/asm/delay.h
@@ -0,0 +1,75 @@
+/*
+ * include/asm-xtensa/delay.h
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2001 - 2005 Tensilica Inc.
+ *
+ */
+
+#ifndef _XTENSA_DELAY_H
+#define _XTENSA_DELAY_H
+
+#include <asm/timex.h>
+#include <asm/param.h>
+
+extern unsigned long loops_per_jiffy;
+
+static inline void __delay(unsigned long loops)
+{
+	if (__builtin_constant_p(loops) && loops < 2)
+		__asm__ __volatile__ ("nop");
+	else if (loops >= 2)
+		/* 2 cycles per loop. */
+		__asm__ __volatile__ ("1: addi %0, %0, -2; bgeui %0, 2, 1b"
+				: "+r" (loops));
+}
+
+/* Undefined function to get compile-time error */
+void __bad_udelay(void);
+void __bad_ndelay(void);
+
+#define __MAX_UDELAY 30000
+#define __MAX_NDELAY 30000
+
+static inline void __udelay(unsigned long usecs)
+{
+	unsigned long start = get_ccount();
+	unsigned long cycles = (usecs * (ccount_freq >> 15)) >> 5;
+
+	/* Note: all variables are unsigned (can wrap around)! */
+	while (((unsigned long)get_ccount()) - start < cycles)
+		cpu_relax();
+}
+
+static inline void udelay(unsigned long usec)
+{
+	if (__builtin_constant_p(usec) && usec >= __MAX_UDELAY)
+		__bad_udelay();
+	else
+		__udelay(usec);
+}
+
+static inline void __ndelay(unsigned long nsec)
+{
+	/*
+	 * Inner shift makes sure multiplication doesn't overflow
+	 * for legitimate nsec values
+	 */
+	unsigned long cycles = (nsec * (ccount_freq >> 15)) >> 15;
+	__delay(cycles);
+}
+
+#define ndelay(n) ndelay(n)
+
+static inline void ndelay(unsigned long nsec)
+{
+	if (__builtin_constant_p(nsec) && nsec >= __MAX_NDELAY)
+		__bad_ndelay();
+	else
+		__ndelay(nsec);
+}
+
+#endif