[PATCH v5 01/26] ARM: shmobile: Add watchdog support

Fabrizio Castro fabrizio.castro at bp.renesas.com
Wed Feb 28 09:37:39 PST 2018


Hi Geert,

thank you for your feedback!

> Subject: Re: [PATCH v5 01/26] ARM: shmobile: Add watchdog support
>
> Hi Fabrizio,
>
> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
> <fabrizio.castro at bp.renesas.com> wrote:
> > On R-Car Gen2 and RZ/G1 platforms, we use the SBAR registers to make non
> > boot CPUs run a routine designed to bring up SMP and deal with hot plug.
> > The value contained in the SBAR registers is not initialized by a WDT
> > triggered reset, which means that after a WDT triggered reset we jump
> > to the SMP bring up routine, preventing the system from executing the
> > bootrom code.
> >
> > The purpose of this patch is to jump to the bootrom code in case of a
> > WDT triggered reset, and keep the SMP functionality untouched.
> > In order to tell if the code had been called due to the WDT overflowing
> > we are testing WOVF from register RWTCSRA.
> >
> > The new function shmobile_boot_vector_gen2 isn't replacing
> > shmobile_boot_vector for backward compatibility reasons. The kernel
> > will install the best option (either shmobile_boot_vector or
> > shmobile_boot_vector_gen2) to ICRAM1 after parsing the device tree,
> > according to the amount of memory available.
> >
> > Since shmobile_boot_vector has become bigger, "reg" property of nodes
> > compatible with "renesas,smp-sram" now need to be set to a value
> > greater or equal to "<0 0x60>".
> >
> > Signed-off-by: Fabrizio Castro <fabrizio.castro at bp.renesas.com>
> > Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram at bp.renesas.com>
>
> > --- a/arch/arm/mach-shmobile/common.h
> > +++ b/arch/arm/mach-shmobile/common.h
> > @@ -7,6 +7,12 @@ extern void shmobile_init_delay(void);
> >  extern void shmobile_boot_vector(void);
> >  extern unsigned long shmobile_boot_fn;
> >  extern unsigned long shmobile_boot_size;
> > +#ifdef CONFIG_ARCH_RCAR_GEN2
>
> I think this #ifdef can be removed.

I'll send a new version of this patch without ifdefs.

Thanks,
Fab

>
> > +extern void shmobile_boot_vector_gen2(void);
> > +extern unsigned long shmobile_boot_fn_gen2;
> > +extern unsigned long shmobile_boot_cpu_gen2;
> > +extern unsigned long shmobile_boot_size_gen2;
> > +#endif /* CONFIG_ARCH_RCAR_GEN2 */
> >  extern void shmobile_smp_boot(void);
> >  extern void shmobile_smp_sleep(void);
> >  extern void shmobile_smp_hook(unsigned int cpu, unsigned long fn,
>
> Apart from that:
> Reviewed-by: Geert Uytterhoeven <geert+renesas at glider.be>
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds



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