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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/metag/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/metag/lib/delay.c')
-rw-r--r--kernel/arch/metag/lib/delay.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/kernel/arch/metag/lib/delay.c b/kernel/arch/metag/lib/delay.c
new file mode 100644
index 000000000..0b308f48b
--- /dev/null
+++ b/kernel/arch/metag/lib/delay.c
@@ -0,0 +1,56 @@
+/*
+ * Precise Delay Loops for Meta
+ *
+ * Copyright (C) 1993 Linus Torvalds
+ * Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
+ * Copyright (C) 2007,2009 Imagination Technologies Ltd.
+ *
+ */
+
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+
+#include <asm/core_reg.h>
+#include <asm/processor.h>
+
+/*
+ * TXTACTCYC is only 24 bits, so on chips with fast clocks it will wrap
+ * many times per-second. If it does wrap __delay will return prematurely,
+ * but this is only likely with large delay values.
+ *
+ * We also can't implement read_current_timer() with TXTACTCYC due to
+ * this wrapping behaviour.
+ */
+#define rdtimer(t) t = __core_reg_get(TXTACTCYC)
+
+void __delay(unsigned long loops)
+{
+ unsigned long bclock, now;
+
+ rdtimer(bclock);
+ do {
+ asm("NOP");
+ rdtimer(now);
+ } while ((now-bclock) < loops);
+}
+EXPORT_SYMBOL(__delay);
+
+inline void __const_udelay(unsigned long xloops)
+{
+ u64 loops = (u64)xloops * (u64)loops_per_jiffy * HZ;
+ __delay(loops >> 32);
+}
+EXPORT_SYMBOL(__const_udelay);
+
+void __udelay(unsigned long usecs)
+{
+ __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
+}
+EXPORT_SYMBOL(__udelay);
+
+void __ndelay(unsigned long nsecs)
+{
+ __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
+}
+EXPORT_SYMBOL(__ndelay);