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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/arm/lib/delay-loop.S
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/arm/lib/delay-loop.S')
-rw-r--r--kernel/arch/arm/lib/delay-loop.S68
1 files changed, 68 insertions, 0 deletions
diff --git a/kernel/arch/arm/lib/delay-loop.S b/kernel/arch/arm/lib/delay-loop.S
new file mode 100644
index 000000000..518bf6e93
--- /dev/null
+++ b/kernel/arch/arm/lib/delay-loop.S
@@ -0,0 +1,68 @@
+/*
+ * linux/arch/arm/lib/delay.S
+ *
+ * Copyright (C) 1995, 1996 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/delay.h>
+ .text
+
+.LC0: .word loops_per_jiffy
+.LC1: .word UDELAY_MULT
+
+/*
+ * r0 <= 2000
+ * lpj <= 0x01ffffff (max. 3355 bogomips)
+ * HZ <= 1000
+ */
+
+ENTRY(__loop_udelay)
+ ldr r2, .LC1
+ mul r0, r2, r0
+ENTRY(__loop_const_udelay) @ 0 <= r0 <= 0x7fffff06
+ mov r1, #-1
+ ldr r2, .LC0
+ ldr r2, [r2] @ max = 0x01ffffff
+ add r0, r0, r1, lsr #32-14
+ mov r0, r0, lsr #14 @ max = 0x0001ffff
+ add r2, r2, r1, lsr #32-10
+ mov r2, r2, lsr #10 @ max = 0x00007fff
+ mul r0, r2, r0 @ max = 2^32-1
+ add r0, r0, r1, lsr #32-6
+ movs r0, r0, lsr #6
+ reteq lr
+
+/*
+ * loops = r0 * HZ * loops_per_jiffy / 1000000
+ */
+ .align 3
+
+@ Delay routine
+ENTRY(__loop_delay)
+ subs r0, r0, #1
+#if 0
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+ retls lr
+ subs r0, r0, #1
+#endif
+ bhi __loop_delay
+ ret lr
+ENDPROC(__loop_udelay)
+ENDPROC(__loop_const_udelay)
+ENDPROC(__loop_delay)