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authorBryan Wu <cooloney@kernel.org>2008-08-27 10:51:02 +0800
committerBryan Wu <cooloney@kernel.org>2008-08-27 10:51:02 +0800
commit639f6571458948b5112be2cf00c0c2c04db2897d (patch)
treea4dd7af33d0e92c935ba1e904f6fb7e923ac825e /arch/blackfin/include/asm/delay.h
parent3d9b7a5ce534f3963afcf8f4777267e5899fe007 (diff)
Blackfin arch: move include/asm-blackfin header files to arch/blackfin
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Diffstat (limited to 'arch/blackfin/include/asm/delay.h')
-rw-r--r--arch/blackfin/include/asm/delay.h62
1 files changed, 62 insertions, 0 deletions
diff --git a/arch/blackfin/include/asm/delay.h b/arch/blackfin/include/asm/delay.h
new file mode 100644
index 00000000000..0889c3abb59
--- /dev/null
+++ b/arch/blackfin/include/asm/delay.h
@@ -0,0 +1,62 @@
+/*
+ * delay.h - delay functions
+ *
+ * Copyright (c) 2004-2007 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#ifndef __ASM_DELAY_H__
+#define __ASM_DELAY_H__
+
+#include <mach/anomaly.h>
+
+static inline void __delay(unsigned long loops)
+{
+ if (ANOMALY_05000312) {
+ /* Interrupted loads to loop registers -> bad */
+ unsigned long tmp;
+ __asm__ __volatile__(
+ "[--SP] = LC0;"
+ "[--SP] = LT0;"
+ "[--SP] = LB0;"
+ "LSETUP (1f,1f) LC0 = %1;"
+ "1: NOP;"
+ /* We take advantage of the fact that LC0 is 0 at
+ * the end of the loop. Otherwise we'd need some
+ * NOPs after the CLI here.
+ */
+ "CLI %0;"
+ "LB0 = [SP++];"
+ "LT0 = [SP++];"
+ "LC0 = [SP++];"
+ "STI %0;"
+ : "=d" (tmp)
+ : "a" (loops)
+ );
+ } else
+ __asm__ __volatile__ (
+ "LSETUP(1f, 1f) LC0 = %0;"
+ "1: NOP;"
+ :
+ : "a" (loops)
+ : "LT0", "LB0", "LC0"
+ );
+}
+
+#include <linux/param.h> /* needed for HZ */
+
+/*
+ * Use only for very small delays ( < 1 msec). Should probably use a
+ * lookup table, really, as the multiplications take much too long with
+ * short delays. This is a "reasonable" implementation, though (and the
+ * first constant multiplications gets optimized away if the delay is
+ * a constant)
+ */
+static inline void udelay(unsigned long usecs)
+{
+ extern unsigned long loops_per_jiffy;
+ __delay(usecs * loops_per_jiffy / (1000000 / HZ));
+}
+
+#endif