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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/sh/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/sh/lib/delay.c')
-rw-r--r--kernel/arch/sh/lib/delay.c53
1 files changed, 53 insertions, 0 deletions
diff --git a/kernel/arch/sh/lib/delay.c b/kernel/arch/sh/lib/delay.c
new file mode 100644
index 000000000..0901b2f14
--- /dev/null
+++ b/kernel/arch/sh/lib/delay.c
@@ -0,0 +1,53 @@
+/*
+ * Precise Delay Loops for SuperH
+ *
+ * Copyright (C) 1999 Niibe Yutaka & Kaz Kojima
+ */
+
+#include <linux/sched.h>
+#include <linux/delay.h>
+
+void __delay(unsigned long loops)
+{
+ __asm__ __volatile__(
+ /*
+ * ST40-300 appears to have an issue with this code,
+ * normally taking two cycles each loop, as with all
+ * other SH variants. If however the branch and the
+ * delay slot straddle an 8 byte boundary, this increases
+ * to 3 cycles.
+ * This align directive ensures this doesn't occur.
+ */
+ ".balign 8\n\t"
+
+ "tst %0, %0\n\t"
+ "1:\t"
+ "bf/s 1b\n\t"
+ " dt %0"
+ : "=r" (loops)
+ : "0" (loops)
+ : "t");
+}
+
+inline void __const_udelay(unsigned long xloops)
+{
+ xloops *= 4;
+ __asm__("dmulu.l %0, %2\n\t"
+ "sts mach, %0"
+ : "=r" (xloops)
+ : "0" (xloops),
+ "r" (cpu_data[raw_smp_processor_id()].loops_per_jiffy * (HZ/4))
+ : "macl", "mach");
+ __delay(++xloops);
+}
+
+void __udelay(unsigned long usecs)
+{
+ __const_udelay(usecs * 0x000010c6); /* 2**32 / 1000000 */
+}
+
+void __ndelay(unsigned long nsecs)
+{
+ __const_udelay(nsecs * 0x00000005);
+}
+