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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 00:20:36 +0200
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 00:20:36 +0200
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sh64/lib/udelay.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
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 'arch/sh64/lib/udelay.c')
-rw-r--r--arch/sh64/lib/udelay.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/arch/sh64/lib/udelay.c b/arch/sh64/lib/udelay.c
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+++ b/arch/sh64/lib/udelay.c
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+/*
+ * arch/sh64/lib/udelay.c
+ *
+ * Delay routines, using a pre-computed "loops_per_jiffy" value.
+ *
+ * Copyright (C) 2000, 2001 Paolo Alberelli
+ * Copyright (C) 2003, 2004 Paul Mundt
+ *
+ * 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.
+ */
+#include <linux/config.h>
+#include <linux/sched.h>
+#include <asm/param.h>
+
+extern unsigned long loops_per_jiffy;
+
+/*
+ * Use only for very small delays (< 1 msec).
+ *
+ * The active part of our cycle counter is only 32-bits wide, and
+ * we're treating the difference between two marks as signed. On
+ * a 1GHz box, that's about 2 seconds.
+ */
+
+void __delay(int loops)
+{
+ long long dummy;
+ __asm__ __volatile__("gettr tr0, %1\n\t"
+ "pta $+4, tr0\n\t"
+ "addi %0, -1, %0\n\t"
+ "bne %0, r63, tr0\n\t"
+ "ptabs %1, tr0\n\t":"=r"(loops),
+ "=r"(dummy)
+ :"0"(loops));
+}
+
+void __udelay(unsigned long long usecs, unsigned long lpj)
+{
+ usecs *= (((unsigned long long) HZ << 32) / 1000000) * lpj;
+ __delay((long long) usecs >> 32);
+}
+
+void __ndelay(unsigned long long nsecs, unsigned long lpj)
+{
+ nsecs *= (((unsigned long long) HZ << 32) / 1000000000) * lpj;
+ __delay((long long) nsecs >> 32);
+}
+
+void udelay(unsigned long usecs)
+{
+ __udelay(usecs, loops_per_jiffy);
+}
+
+void ndelay(unsigned long nsecs)
+{
+ __ndelay(nsecs, loops_per_jiffy);
+}
+