[PATCH 1/2] ARM/MXS: add new way to reset the whole SoC

[Juergen Beisert]

Hi Uwe,

Uwe Kleine-König wrote:
> On Wed, Jun 20, 2012 at 03:49:12PM +0200, Juergen Beisert wrote:
> > Currently the watchdog is occupied for system reset. This usage collides
> > with the dedicated usage of a watchdog. This patch change the behaviour
> > of at least i.MX23/i.MX28 where the chipset supports a simple and
> > powerful alternative to reset the whole SoC (including the PMIC).
> >
> > Signed-off-by: Juergen Beisert <jbe at pengutronix.de>
> > ---
> >  arch/arm/mach-mxs/soc-imx23.c |   37
> > +++++++++++++++++++++++++++++++++++++ arch/arm/mach-mxs/soc-imx28.c |  
> > 37 +++++++++++++++++++++++++++++++++++++ 2 files changed, 74
> > insertions(+)
> >  create mode 100644 arch/arm/mach-mxs/soc-imx23.c
> >  create mode 100644 arch/arm/mach-mxs/soc-imx28.c
> >
> > diff --git a/arch/arm/mach-mxs/soc-imx23.c
> > b/arch/arm/mach-mxs/soc-imx23.c new file mode 100644
> > index 0000000..964b722
> > --- /dev/null
> > +++ b/arch/arm/mach-mxs/soc-imx23.c
> > @@ -0,0 +1,37 @@
> > +/*
> > + * (c) 2012 Juergen Beisert <kernel at pengutronix.de>
> > + *
> > + * 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.
> > + *
> > + * Collection of some SoC specific functions
> > + */
> > +
> > +#include <common.h>
> > +#include <init.h>
> > +#include <mach/imx-regs.h>
> > +#include <io.h>
> > +
> > +#define HW_CLKCTRL_RESET 0x120
> > +# define HW_CLKCTRL_RESET_CHIP (1 << 1)
> > +
> > +/* Reset the full i.MX23 SoC via a chipset feature */
> > +void __noreturn reset_cpu (unsigned long addr)
>
> coding style ---------------^, no space here.

Okay.

> > +{
> > +	u32 reg;
> > +
> > +	reg = readl(IMX_CCM_BASE + HW_CLKCTRL_RESET);
> > +	writel(reg | HW_CLKCTRL_RESET_CHIP, IMX_CCM_BASE + HW_CLKCTRL_RESET);
> > +
> > +	while (1)
> > +		;
> > +	/*NOTREACHED*/
> > +}
> > +EXPORT_SYMBOL(reset_cpu);
> > diff --git a/arch/arm/mach-mxs/soc-imx28.c
> > b/arch/arm/mach-mxs/soc-imx28.c new file mode 100644
> > index 0000000..c7a34a8
> > --- /dev/null
> > +++ b/arch/arm/mach-mxs/soc-imx28.c
> > @@ -0,0 +1,37 @@
> > +/*
> > + * (c) 2012 Juergen Beisert <kernel at pengutronix.de>
> > + *
> > + * 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.
> > + *
> > + * Collection of some SoC specific functions
> > + */
> > +
> > +#include <common.h>
> > +#include <init.h>
> > +#include <mach/imx-regs.h>
> > +#include <io.h>
> > +
> > +#define HW_CLKCTRL_RESET 0x1e0
> > +# define HW_CLKCTRL_RESET_CHIP (1 << 1)
> > +
> > +/* Reset the full i.MX28 SoC via a chipset feature */
> > +void __noreturn reset_cpu (unsigned long addr)
> > +{
> > +	u32 reg;
> > +
> > +	reg = readl(IMX_CCM_BASE + HW_CLKCTRL_RESET);
> > +	writel(reg | HW_CLKCTRL_RESET_CHIP, IMX_CCM_BASE + HW_CLKCTRL_RESET);
> > +
> > +	while (1)
> > +		;
> > +	/*NOTREACHED*/
> > +}
> > +EXPORT_SYMBOL(reset_cpu);
>
> Is it worth to introduce a common function
>
> 	void __noreturn sensiblename(unsigned long clkctrl_reset_offset, unsigned
> long unused) {
> 		...
> 	}
>
> and make the reset_cpu functions for imx23 and imx28 just call
> sensiblename()?

Refer "http://www.spinics.net/lists/u-boot-v2/msg07681.html"

jbe

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