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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/mips/lib/delay.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/mips/lib/delay.c')
-rw-r--r--kernel/arch/mips/lib/delay.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/kernel/arch/mips/lib/delay.c b/kernel/arch/mips/lib/delay.c
new file mode 100644
index 000000000..21d27c681
--- /dev/null
+++ b/kernel/arch/mips/lib/delay.c
@@ -0,0 +1,64 @@
+/*
+ * 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) 1994 by Waldorf Electronics
+ * Copyright (C) 1995 - 2000, 01, 03 by Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2007, 2014 Maciej W. Rozycki
+ */
+#include <linux/module.h>
+#include <linux/param.h>
+#include <linux/smp.h>
+#include <linux/stringify.h>
+
+#include <asm/asm.h>
+#include <asm/compiler.h>
+#include <asm/war.h>
+
+#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
+#define GCC_DADDI_IMM_ASM() "I"
+#else
+#define GCC_DADDI_IMM_ASM() "r"
+#endif
+
+void __delay(unsigned long loops)
+{
+ __asm__ __volatile__ (
+ " .set noreorder \n"
+ " .align 3 \n"
+ "1: bnez %0, 1b \n"
+ " " __stringify(LONG_SUBU) " %0, %1 \n"
+ " .set reorder \n"
+ : "=r" (loops)
+ : GCC_DADDI_IMM_ASM() (1), "0" (loops));
+}
+EXPORT_SYMBOL(__delay);
+
+/*
+ * Division by multiplication: you don't have to worry about
+ * loss of precision.
+ *
+ * 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)
+ */
+
+void __udelay(unsigned long us)
+{
+ unsigned int lpj = raw_current_cpu_data.udelay_val;
+
+ __delay((us * 0x000010c7ull * HZ * lpj) >> 32);
+}
+EXPORT_SYMBOL(__udelay);
+
+void __ndelay(unsigned long ns)
+{
+ unsigned int lpj = raw_current_cpu_data.udelay_val;
+
+ __delay((ns * 0x00000005ull * HZ * lpj) >> 32);
+}
+EXPORT_SYMBOL(__ndelay);