Re: [PATCH v2 4/5] ARM: EXYNOS: add exynos_get_boot_addr() helper

From: Krzysztof Kozlowski
Date: Wed Mar 18 2015 - 11:21:43 EST


On Åro, 2015-03-18 at 16:18 +0100, Bartlomiej Zolnierkiewicz wrote:
> On Wednesday, March 18, 2015 02:43:49 PM Krzysztof Kozlowski wrote:
> > 2015-03-18 14:09 GMT+01:00 Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>:
> > > Add get_cpu_boot_addr() firmware operation and then
> > > exynos_get_boot_addr() helper.
> > >
> > > This is a preparation for adding coupled cpuidle support
> > > for Exynos3250 SoC.
> > >
> > > There should be no functional changes caused by this patch.
> > >
> > > Cc: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
> > > Cc: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
> > > Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
> > > ---
> > > arch/arm/include/asm/firmware.h | 4 ++++
> > > arch/arm/mach-exynos/firmware.c | 17 +++++++++++++++++
> > > arch/arm/mach-exynos/platsmp.c | 25 +++++++++++++++++++++++++
> > > 3 files changed, 46 insertions(+)
> > >
> > > diff --git a/arch/arm/include/asm/firmware.h b/arch/arm/include/asm/firmware.h
> > > index 89aefe1..34c1d96 100644
> > > --- a/arch/arm/include/asm/firmware.h
> > > +++ b/arch/arm/include/asm/firmware.h
> > > @@ -34,6 +34,10 @@ struct firmware_ops {
> > > */
> > > int (*set_cpu_boot_addr)(int cpu, unsigned long boot_addr);
> > > /*
> > > + * Gets boot address of specified physical CPU
> > > + */
> > > + int (*get_cpu_boot_addr)(int cpu, unsigned long *boot_addr);
> > > + /*
> > > * Boots specified physical CPU
> > > */
> > > int (*cpu_boot)(int cpu);
> > > diff --git a/arch/arm/mach-exynos/firmware.c b/arch/arm/mach-exynos/firmware.c
> > > index f236877..c9e4481 100644
> > > --- a/arch/arm/mach-exynos/firmware.c
> > > +++ b/arch/arm/mach-exynos/firmware.c
> > > @@ -104,6 +104,22 @@ static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
> > > return 0;
> > > }
> > >
> > > +static int exynos_get_cpu_boot_addr(int cpu, unsigned long *boot_addr)
> > > +{
> > > + void __iomem *boot_reg;
> > > +
> > > + if (!sysram_ns_base_addr)
> > > + return -ENODEV;
> > > +
> > > + boot_reg = sysram_ns_base_addr + 0x1c;
> > > +
> > > + if (soc_is_exynos4412())
> > > + boot_reg += 4 * cpu;
> > > +
> > > + *boot_addr = __raw_readl(boot_reg);
> > > + return 0;
> > > +}
> > > +
> > > static int exynos_cpu_suspend(unsigned long arg)
> > > {
> > > flush_cache_all();
> > > @@ -138,6 +154,7 @@ static int exynos_resume(void)
> > > static const struct firmware_ops exynos_firmware_ops = {
> > > .do_idle = IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_do_idle : NULL,
> > > .set_cpu_boot_addr = exynos_set_cpu_boot_addr,
> > > + .get_cpu_boot_addr = exynos_get_cpu_boot_addr,
> > > .cpu_boot = exynos_cpu_boot,
> > > .suspend = IS_ENABLED(CONFIG_PM_SLEEP) ? exynos_suspend : NULL,
> > > .resume = IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_resume : NULL,
> > > diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c
> > > index b7cfcdc..449edd1 100644
> > > --- a/arch/arm/mach-exynos/platsmp.c
> > > +++ b/arch/arm/mach-exynos/platsmp.c
> > > @@ -272,6 +272,31 @@ fail:
> > > return ret;
> > > }
> > >
> > > +static int exynos_get_boot_addr(u32 core_id, unsigned long *boot_addr)
> > > +{
> > > + int ret;
> > > +
> > > + /*
> > > + * Try to get boot address using firmware first
> > > + * and fall back to boot register if it fails.
> > > + */
> > > + ret = call_firmware_op(get_cpu_boot_addr, core_id, boot_addr);
> > > + if (ret && ret != -ENOSYS)
> > > + goto fail;
> >
> > The exynos_get_cpu_boot_addr() returns ENODEV. Do you really want to
> > check for ENOSYS here?
>
> Yes. When secure firmware is not present on the board the call_firmware_op()
> itself returns -ENOSYS (exynos_get_cpu_boot_addr() is not called in this
> case) and it needs to be handled in a special way.

Right, my mistake. Rest looks good:

Reviewed-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>

Best regards,
Krzysztof




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