summaryrefslogtreecommitdiffstats
path: root/qemu/roms/u-boot/lib/rand.c
diff options
context:
space:
mode:
authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/u-boot/lib/rand.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/u-boot/lib/rand.c')
-rw-r--r--qemu/roms/u-boot/lib/rand.c32
1 files changed, 32 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/lib/rand.c b/qemu/roms/u-boot/lib/rand.c
new file mode 100644
index 000000000..5c367e186
--- /dev/null
+++ b/qemu/roms/u-boot/lib/rand.c
@@ -0,0 +1,32 @@
+/*
+ * Simple xorshift PRNG
+ * see http://www.jstatsoft.org/v08/i14/paper
+ *
+ * Copyright (c) 2012 Michael Walle
+ * Michael Walle <michael@walle.cc>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+
+static unsigned int y = 1U;
+
+unsigned int rand_r(unsigned int *seedp)
+{
+ *seedp ^= (*seedp << 13);
+ *seedp ^= (*seedp >> 17);
+ *seedp ^= (*seedp << 5);
+
+ return *seedp;
+}
+
+unsigned int rand(void)
+{
+ return rand_r(&y);
+}
+
+void srand(unsigned int seed)
+{
+ y = seed;
+}