[U-Boot] [PATCH V2] imx: mx7: psci: add system reset support

[Anson Huang]

Hi, Peng

Best Regards!
Anson Huang


> -----Original Message-----
> From: Peng Fan
> Sent: 2018-01-04 5:48 PM
> To: Anson Huang <anson.huang at nxp.com>; sbabic at denx.de; Fabio Estevam
> <fabio.estevam at nxp.com>; albert.u.boot at aribaud.net;
> christian.gmeiner at gmail.com; u-boot at lists.denx.de
> Subject: RE: [PATCH V2] imx: mx7: psci: add system reset support
> 
> Hi Anson,
> 
> > -----Original Message-----
> > From: Anson Huang [mailto:Anson.Huang at nxp.com]
> > Sent: Thursday, January 04, 2018 5:04 PM
> > To: sbabic at denx.de; Fabio Estevam <fabio.estevam at nxp.com>;
> > albert.u.boot at aribaud.net; christian.gmeiner at gmail.com; Peng Fan
> > <peng.fan at nxp.com>; u-boot at lists.denx.de
> > Subject: [PATCH V2] imx: mx7: psci: add system reset support
> >
> > Add i.MX7 PSCI system reset support, linux kernel now can use "reboot"
> > command to reset system.
> >
> > Signed-off-by: Anson Huang <Anson.Huang at nxp.com>
> > ---
> > changes since V1:
> > 	write WDOG register directly instead of calling reset_cpu
> > 	which is NOT safe since it is NOT in secure section.
> >  arch/arm/mach-imx/mx7/psci-mx7.c | 5 +++++
> >  arch/arm/mach-imx/mx7/psci.S     | 7 +++++++
> >  2 files changed, 12 insertions(+)
> >
> > diff --git a/arch/arm/mach-imx/mx7/psci-mx7.c b/arch/arm/mach-
> > imx/mx7/psci-mx7.c index 7f429b0..66f6db6 100644
> > --- a/arch/arm/mach-imx/mx7/psci-mx7.c
> > +++ b/arch/arm/mach-imx/mx7/psci-mx7.c
> > @@ -74,3 +74,8 @@ __secure int imx_cpu_off(int cpu)
> >  	writel(0, SRC_BASE_ADDR + cpu * 8 + SRC_GPR1_MX7D + 4);
> >  	return 0;
> >  }
> > +
> > +__secure void imx_system_reset(void)
> > +{
> > +	writew(1 << 2, WDOG1_BASE_ADDR);
> 
> I think this should be "writew((WCR_WDE | WCR_SRS),
> WDOG1_BASE_ADDR);"?

I use SRS reset which will assert reset signal immediately, no need to wait
Wdog timeout.


Anson.

> 
> Regards,
> Peng.
> 
> > +}
> > diff --git a/arch/arm/mach-imx/mx7/psci.S
> > b/arch/arm/mach-imx/mx7/psci.S index fc5eb34..59f98cd 100644
> > --- a/arch/arm/mach-imx/mx7/psci.S
> > +++ b/arch/arm/mach-imx/mx7/psci.S
> > @@ -43,4 +43,11 @@ psci_cpu_off:
> >  1: 	wfi
> >  	b 1b
> >
> > +.globl psci_system_reset
> > +psci_system_reset:
> > +	b	imx_system_reset
> > +
> > +2: 	wfi
> > +	b 2b
> > +
> >  	.popsection
> > --
> > 1.9.1