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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/ia64/lib/carta_random.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/ia64/lib/carta_random.S')
-rw-r--r--kernel/arch/ia64/lib/carta_random.S54
1 files changed, 54 insertions, 0 deletions
diff --git a/kernel/arch/ia64/lib/carta_random.S b/kernel/arch/ia64/lib/carta_random.S
new file mode 100644
index 000000000..d0674c360
--- /dev/null
+++ b/kernel/arch/ia64/lib/carta_random.S
@@ -0,0 +1,54 @@
+/*
+ * Fast, simple, yet decent quality random number generator based on
+ * a paper by David G. Carta ("Two Fast Implementations of the
+ * `Minimal Standard' Random Number Generator," Communications of the
+ * ACM, January, 1990).
+ *
+ * Copyright (C) 2002 Hewlett-Packard Co
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ */
+
+#include <asm/asmmacro.h>
+
+#define a r2
+#define m r3
+#define lo r8
+#define hi r9
+#define t0 r16
+#define t1 r17
+#define seed r32
+
+GLOBAL_ENTRY(carta_random32)
+ movl a = (16807 << 16) | 16807
+ ;;
+ pmpyshr2.u t0 = a, seed, 0
+ pmpyshr2.u t1 = a, seed, 16
+ ;;
+ unpack2.l t0 = t1, t0
+ dep m = -1, r0, 0, 31
+ ;;
+ zxt4 lo = t0
+ shr.u hi = t0, 32
+ ;;
+ dep t0 = 0, hi, 15, 49 // t0 = (hi & 0x7fff)
+ ;;
+ shl t0 = t0, 16 // t0 = (hi & 0x7fff) << 16
+ shr t1 = hi, 15 // t1 = (hi >> 15)
+ ;;
+ add lo = lo, t0
+ ;;
+ cmp.gtu p6, p0 = lo, m
+ ;;
+(p6) and lo = lo, m
+ ;;
+(p6) add lo = 1, lo
+ ;;
+ add lo = lo, t1
+ ;;
+ cmp.gtu p6, p0 = lo, m
+ ;;
+(p6) and lo = lo, m
+ ;;
+(p6) add lo = 1, lo
+ br.ret.sptk.many rp
+END(carta_random32)