Patchwork [U-Boot,v5,1/5] lib: add rand() function

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Submitter Michael Walle
Date May 11, 2012, 10:50 p.m.
Message ID <1336776649-9316-2-git-send-email-michael@walle.cc>
Download mbox | patch
Permalink /patch/158623/
State Superseded
Delegated to: Prafulla Wadaskar
Headers show

Comments

Michael Walle - May 11, 2012, 10:50 p.m.
It's a PRNG using the simple and fast xorshift method.

Signed-off-by: Michael Walle <michael@walle.cc>
Cc: Wolfgang Denk <wd@denx.de>
---
 include/common.h |    6 ++++++
 lib/Makefile     |    1 +
 lib/rand.c       |   43 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 50 insertions(+), 0 deletions(-)
 create mode 100644 lib/rand.c
Michael Walle - May 23, 2012, 4:34 p.m.
Am Samstag 12 Mai 2012, 00:50:45 schrieb Michael Walle:
> It's a PRNG using the simple and fast xorshift method.
> 
> Signed-off-by: Michael Walle <michael@walle.cc>
> Cc: Wolfgang Denk <wd@denx.de>


Hi Wolfgang,

can you ack this patch? In that case i could add the acked-by line in the next 
version of this patch series to ease the picking by Prafulla. All your 
previous comments should be addressed :)


> ---
>  include/common.h |    6 ++++++
>  lib/Makefile     |    1 +
>  lib/rand.c       |   43 +++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 50 insertions(+), 0 deletions(-)
>  create mode 100644 lib/rand.c
> 
> diff --git a/include/common.h b/include/common.h
> index 4b5841e..a9cb62c 100644
> --- a/include/common.h
> +++ b/include/common.h
> @@ -733,6 +733,12 @@ char *	strmhz(char *buf, unsigned long hz);
>  /* lib/crc32.c */
>  #include <u-boot/crc.h>
> 
> +/* lib/rand.c */
> +#ifdef CONFIG_RANDOM_MACADDR
> +void srand(unsigned int seed);
> +unsigned int rand(void);
> +#endif
> +
>  /* common/console.c */
>  int	console_init_f(void);	/* Before relocation; uses the serial  stuff	
*/
>  int	console_init_r(void);	/* After  relocation; uses the console stuff	
*/
> diff --git a/lib/Makefile b/lib/Makefile
> index a0fec60..74579f9 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -65,6 +65,7 @@ COBJS-y += string.o
>  COBJS-y += time.o
>  COBJS-$(CONFIG_BOOTP_PXE) += uuid.o
>  COBJS-y += vsprintf.o
> +COBJS-$(CONFIG_RANDOM_MACADDR) += rand.o
> 
>  COBJS	:= $(COBJS-y)
>  SRCS	:= $(COBJS:.o=.c)
> diff --git a/lib/rand.c b/lib/rand.c
> new file mode 100644
> index 0000000..6cb76ac
> --- /dev/null
> +++ b/lib/rand.c
> @@ -0,0 +1,43 @@
> +/*
> + * Simple xorshift PRNG
> + *   see http://www.jstatsoft.org/v08/i14/paper
> + *
> + * Copyright (c) 2012 Michael Walle
> + * Michael Walle <michael@walle.cc>
> + *
> + * See file CREDITS for list of people who contributed to this
> + * project.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
> + * MA 02111-1307 USA
> + */
> +
> +#include <common.h>
> +
> +static unsigned int y = 1U;
> +
> +void srand(unsigned int seed)
> +{
> +	y = seed;
> +}
> +
> +unsigned int rand(void)
> +{
> +	y ^= (y << 13);
> +	y ^= (y >> 17);
> +	y ^= (y << 5);
> +
> +	return y;
> +}
Prafulla Wadaskar - May 24, 2012, 4:32 a.m.
> -----Original Message-----
> From: Michael Walle [mailto:michael@walle.cc]
> Sent: 23 May 2012 22:05
> To: u-boot@lists.denx.de
> Cc: Prafulla Wadaskar; Wolfgang Denk
> Subject: Re: [PATCH v5 1/5] lib: add rand() function
> 
> Am Samstag 12 Mai 2012, 00:50:45 schrieb Michael Walle:
> > It's a PRNG using the simple and fast xorshift method.
> >
> > Signed-off-by: Michael Walle <michael@walle.cc>
> > Cc: Wolfgang Denk <wd@denx.de>
> 
> 
> Hi Wolfgang,
> 
> can you ack this patch? In that case i could add the acked-by line in
> the next
> version of this patch series to ease the picking by Prafulla. All your
> previous comments should be addressed :)
> 
> 
> > ---
> >  include/common.h |    6 ++++++
> >  lib/Makefile     |    1 +
> >  lib/rand.c       |   43 +++++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 50 insertions(+), 0 deletions(-)
> >  create mode 100644 lib/rand.c
> >

If I consider the files being checked in, those are generic, I would suggest if Wolfgang can pull them.

Regards..
Prafulla . . .
Michael Walle - May 24, 2012, 10:34 a.m.
On Thu, May 24, 2012 06:32, Prafulla Wadaskar wrote:
>> Hi Wolfgang,
>>
>> can you ack this patch? In that case i could add the acked-by line in
>> the next
>> version of this patch series to ease the picking by Prafulla. All your
>> previous comments should be addressed :)
>>
>>
>> > ---
>> >  include/common.h |    6 ++++++
>> >  lib/Makefile     |    1 +
>> >  lib/rand.c       |   43 +++++++++++++++++++++++++++++++++++++++++++
>> >  3 files changed, 50 insertions(+), 0 deletions(-)
>> >  create mode 100644 lib/rand.c
>> >
>
> If I consider the files being checked in, those are generic, I would
> suggest if Wolfgang can pull them.

Wolfgang won't pull this alone, see here:
  http://lists.denx.de/pipermail/u-boot/2012-May/124191.html
and here
  http://lists.denx.de/pipermail/u-boot/2012-May/124202.html

Patch

diff --git a/include/common.h b/include/common.h
index 4b5841e..a9cb62c 100644
--- a/include/common.h
+++ b/include/common.h
@@ -733,6 +733,12 @@  char *	strmhz(char *buf, unsigned long hz);
 /* lib/crc32.c */
 #include <u-boot/crc.h>
 
+/* lib/rand.c */
+#ifdef CONFIG_RANDOM_MACADDR
+void srand(unsigned int seed);
+unsigned int rand(void);
+#endif
+
 /* common/console.c */
 int	console_init_f(void);	/* Before relocation; uses the serial  stuff	*/
 int	console_init_r(void);	/* After  relocation; uses the console stuff	*/
diff --git a/lib/Makefile b/lib/Makefile
index a0fec60..74579f9 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -65,6 +65,7 @@  COBJS-y += string.o
 COBJS-y += time.o
 COBJS-$(CONFIG_BOOTP_PXE) += uuid.o
 COBJS-y += vsprintf.o
+COBJS-$(CONFIG_RANDOM_MACADDR) += rand.o
 
 COBJS	:= $(COBJS-y)
 SRCS	:= $(COBJS:.o=.c)
diff --git a/lib/rand.c b/lib/rand.c
new file mode 100644
index 0000000..6cb76ac
--- /dev/null
+++ b/lib/rand.c
@@ -0,0 +1,43 @@ 
+/*
+ * Simple xorshift PRNG
+ *   see http://www.jstatsoft.org/v08/i14/paper
+ *
+ * Copyright (c) 2012 Michael Walle
+ * Michael Walle <michael@walle.cc>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+
+static unsigned int y = 1U;
+
+void srand(unsigned int seed)
+{
+	y = seed;
+}
+
+unsigned int rand(void)
+{
+	y ^= (y << 13);
+	y ^= (y >> 17);
+	y ^= (y << 5);
+
+	return y;
+}