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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-m68k/delay.h
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-m68k/delay.h')
-rw-r--r--include/asm-m68k/delay.h57
1 files changed, 57 insertions, 0 deletions
diff --git a/include/asm-m68k/delay.h b/include/asm-m68k/delay.h
new file mode 100644
index 000000000000..5ed92851bc6f
--- /dev/null
+++ b/include/asm-m68k/delay.h
@@ -0,0 +1,57 @@
+#ifndef _M68K_DELAY_H
+#define _M68K_DELAY_H
+
+#include <asm/param.h>
+
+/*
+ * Copyright (C) 1994 Hamish Macdonald
+ *
+ * Delay routines, using a pre-computed "loops_per_jiffy" value.
+ */
+
+static inline void __delay(unsigned long loops)
+{
+ __asm__ __volatile__ ("1: subql #1,%0; jcc 1b"
+ : "=d" (loops) : "0" (loops));
+}
+
+extern void __bad_udelay(void);
+
+/*
+ * 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 __const_udelay(unsigned long xloops)
+{
+ unsigned long tmp;
+
+ __asm__ ("mulul %2,%0:%1"
+ : "=d" (xloops), "=d" (tmp)
+ : "d" (xloops), "1" (loops_per_jiffy));
+ __delay(xloops * HZ);
+}
+
+static inline void __udelay(unsigned long usecs)
+{
+ __const_udelay(usecs * 4295); /* 2**32 / 1000000 */
+}
+
+#define udelay(n) (__builtin_constant_p(n) ? \
+ ((n) > 20000 ? __bad_udelay() : __const_udelay((n) * 4295)) : \
+ __udelay(n))
+
+static inline unsigned long muldiv(unsigned long a, unsigned long b,
+ unsigned long c)
+{
+ unsigned long tmp;
+
+ __asm__ ("mulul %2,%0:%1; divul %3,%0:%1"
+ : "=d" (tmp), "=d" (a)
+ : "d" (b), "d" (c), "1" (a));
+ return a;
+}
+
+#endif /* defined(_M68K_DELAY_H) */