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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/cris/arch-v32/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/cris/arch-v32/lib/delay.c')
-rw-r--r--kernel/arch/cris/arch-v32/lib/delay.c28
1 files changed, 28 insertions, 0 deletions
diff --git a/kernel/arch/cris/arch-v32/lib/delay.c b/kernel/arch/cris/arch-v32/lib/delay.c
new file mode 100644
index 000000000..39f1ac999
--- /dev/null
+++ b/kernel/arch/cris/arch-v32/lib/delay.c
@@ -0,0 +1,28 @@
+/*
+ * Precise Delay Loops for ETRAX FS
+ *
+ * Copyright (C) 2006 Axis Communications AB.
+ *
+ */
+
+#include <hwregs/reg_map.h>
+#include <hwregs/reg_rdwr.h>
+#include <hwregs/timer_defs.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+
+/*
+ * On ETRAX FS, we can check the free-running read-only 100MHz timer
+ * getting 32-bit 10ns precision, theoretically good for 42.94967295
+ * seconds. Unsigned arithmetic and careful expression handles
+ * wrapping.
+ */
+
+void cris_delay10ns(u32 n10ns)
+{
+ u32 t0 = REG_RD(timer, regi_timer0, r_time);
+ while (REG_RD(timer, regi_timer0, r_time) - t0 < n10ns)
+ ;
+}
+EXPORT_SYMBOL(cris_delay10ns);