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-rw-r--r--arch/c6x/include/asm/delay.h67
1 files changed, 67 insertions, 0 deletions
diff --git a/arch/c6x/include/asm/delay.h b/arch/c6x/include/asm/delay.h
new file mode 100644
index 00000000000..f314c2e9eb5
--- /dev/null
+++ b/arch/c6x/include/asm/delay.h
@@ -0,0 +1,67 @@
+/*
+ * Port on Texas Instruments TMS320C6x architecture
+ *
+ * Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
+ * Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
+ *
+ * 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.
+ */
+#ifndef _ASM_C6X_DELAY_H
+#define _ASM_C6X_DELAY_H
+
+#include <linux/kernel.h>
+
+extern unsigned int ticks_per_ns_scaled;
+
+static inline void __delay(unsigned long loops)
+{
+ uint32_t tmp;
+
+ /* 6 cycles per loop */
+ asm volatile (" mv .s1 %0,%1\n"
+ "0: [%1] b .s1 0b\n"
+ " add .l1 -6,%0,%0\n"
+ " cmplt .l1 1,%0,%1\n"
+ " nop 3\n"
+ : "+a"(loops), "=A"(tmp));
+}
+
+static inline void _c6x_tickdelay(unsigned int x)
+{
+ uint32_t cnt, endcnt;
+
+ asm volatile (" mvc .s2 TSCL,%0\n"
+ " add .s2x %0,%1,%2\n"
+ " || mvk .l2 1,B0\n"
+ "0: [B0] b .s2 0b\n"
+ " mvc .s2 TSCL,%0\n"
+ " sub .s2 %0,%2,%0\n"
+ " cmpgt .l2 0,%0,B0\n"
+ " nop 2\n"
+ : "=b"(cnt), "+a"(x), "=b"(endcnt) : : "B0");
+}
+
+/* use scaled math to avoid slow division */
+#define C6X_NDELAY_SCALE 10
+
+static inline void _ndelay(unsigned int n)
+{
+ _c6x_tickdelay((ticks_per_ns_scaled * n) >> C6X_NDELAY_SCALE);
+}
+
+static inline void _udelay(unsigned int n)
+{
+ while (n >= 10) {
+ _ndelay(10000);
+ n -= 10;
+ }
+ while (n-- > 0)
+ _ndelay(1000);
+}
+
+#define udelay(x) _udelay((unsigned int)(x))
+#define ndelay(x) _ndelay((unsigned int)(x))
+
+#endif /* _ASM_C6X_DELAY_H */