[U-Boot] [PATCH 3/4] arm: Support new Xilinx Zynq platform

[Michal Simek <monstr@monstr.eu>]

On 08/14/2012 05:36 PM, Joe Hershberger wrote:
> Hi Michal,
>
> On Tue, Aug 14, 2012 at 6:42 AM, Michal Simek <monstr@monstr.eu> wrote:
>> Add timer driver.
>>
>> Signed-off-by: Michal Simek <monstr@monstr.eu>
>> ---
>>   arch/arm/cpu/armv7/zynq/Makefile |   48 ++++++++++++
>>   arch/arm/cpu/armv7/zynq/timer.c  |  151 ++++++++++++++++++++++++++++++++++++++
>>   2 files changed, 199 insertions(+), 0 deletions(-)
>>   create mode 100644 arch/arm/cpu/armv7/zynq/Makefile
>>   create mode 100644 arch/arm/cpu/armv7/zynq/timer.c
>>
>> diff --git a/arch/arm/cpu/armv7/zynq/Makefile b/arch/arm/cpu/armv7/zynq/Makefile
>> new file mode 100644
>> index 0000000..814c1d4
>> --- /dev/null
>> +++ b/arch/arm/cpu/armv7/zynq/Makefile
>> @@ -0,0 +1,48 @@
>> +#
>> +# (C) Copyright 2000-2003
>> +# Wolfgang Denk, DENX Software Engineering, wd at denx.de.
>> +#
>> +# (C) Copyright 2008
>> +# Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
>> +#
>> +# 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 $(TOPDIR)/config.mk
>> +
>> +LIB    = $(obj)lib$(SOC).o
>> +
>
> You should include the lowlevel_init.o here instead of in the board.

Probably make sense.


>
>> +COBJS  = timer.o
>> +
>
> Preferably emulate the Makefile in arch/arm/cpu/armv7/tegra2/.  By
> that I mean use COBJS-y instead of COBJS directly.  This is more
> forward looking to allow for features to be disabled in the future.

no problem with that.

>
>> +SRCS   := $(SOBJS:.o=.S) $(COBJS:.o=.c)
>> +OBJS   := $(addprefix $(obj),$(SOBJS) $(COBJS))
>> +
>> +all:   $(obj).depend $(LIB)
>> +
>> +$(LIB): $(OBJS)
>> +       $(call cmd_link_o_target, $(OBJS))
>> +
>> +#########################################################################
>> +
>> +# defines $(obj).depend target
>> +include $(SRCTREE)/rules.mk
>> +
>> +sinclude $(obj).depend
>> +
>> +#########################################################################
>> diff --git a/arch/arm/cpu/armv7/zynq/timer.c b/arch/arm/cpu/armv7/zynq/timer.c
>> new file mode 100644
>> index 0000000..d79da97
>> --- /dev/null
>> +++ b/arch/arm/cpu/armv7/zynq/timer.c
>> @@ -0,0 +1,151 @@
>> +/*
>> + * Copyright (C) 2012 Michal Simek <monstr@monstr.eu>
>> + * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved.
>> + *
>> + * (C) Copyright 2008
>> + * Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
>> + *
>> + * (C) Copyright 2004
>> + * Philippe Robin, ARM Ltd. <philippe.robin@arm.com>
>> + *
>> + * (C) Copyright 2002-2004
>> + * Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
>> + *
>> + * (C) Copyright 2003
>> + * Texas Instruments <www.ti.com>
>> + *
>> + * (C) Copyright 2002
>> + * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
>> + * Marius Groeger <mgroeger@sysgo.de>
>> + *
>> + * (C) Copyright 2002
>> + * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
>> + * Alex Zuepke <azu@sysgo.de>
>> + *
>> + * 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>
>> +#include <div64.h>
>> +#include <asm/io.h>
>> +
>> +DECLARE_GLOBAL_DATA_PTR;
>> +
>> +struct scu_timer {
>> +       u32 load; /* Timer Load Register */
>> +       u32 counter; /* Timer Counter Register */
>> +       u32 control; /* Timer Control Register */
>> +};
>
> You are using the timer in the ARM Cortex A9 core.  This is not
> Zynq-specific in any way.  It should be made available in a different
> place.  Probably in arch/arm/lib.  It should be stripped on any "XSCU"
> references.  Use ARM names instead.


Based on this I can't see the reason why XSCU should be stripped.
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0407f/BABDEAGJ.html

It is SCU private timer. Agree that we can remove X prefix.


I don't think that arch/arm/lib is the proper location for that.
I am not arm specialist to say that this timer is available in all arm families
to be in lib folder.

Thanks,
Michal

-- 
Michal Simek, Ing. (M.Eng)
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/
Microblaze U-BOOT custodian