linux-kernel - Re: [PATCH v2 1/4] ARM: exynos: clear L310_AUX_CTRL_NS_LOCKDOWN in default l2c_aux

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Date:   Tue, 1 Sep 2020 14:34:25 +0100
From:   Guillaume Tucker <guillaume.tucker@...labora.com>
To:     Russell King <linux@...linux.org.uk>,
        Krzysztof Kozlowski <krzk@...nel.org>
Cc:     Kukjin Kim <kgene@...nel.org>, Rob Herring <robh+dt@...nel.org>,
        kernel@...labora.com, devicetree@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org,
        linux-samsung-soc@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 1/4] ARM: exynos: clear L310_AUX_CTRL_NS_LOCKDOWN in
 default l2c_aux_val

Hi Krzysztof, Russell,

On 10/08/2020 13:22, Guillaume Tucker wrote:
> The L310_AUX_CTRL_NS_LOCKDOWN flag is set during the L2C enable
> sequence.  There is no need to set it in the default register value,
> this was done before support for it was implemented in the code.  It
> is not set in the hardware initial value either.
> 
> Clean this up by removing this flag from the default l2c_aux_val, and
> add it to the l2c_aux_mask to print an alert message if it was already
> set before the kernel initialisation.
> 
> Signed-off-by: Guillaume Tucker <guillaume.tucker@...labora.com>
> ---
> 
> Notes:
>     v2: fix flag name L310_AUX_CTRL_NS_LOCKDOWN
> 
>  arch/arm/mach-exynos/exynos.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

I believe this v2 series has addressed all previous comments and
you were waiting for the 5.9 merge window to end.  The patches
all still apply cleanly on v5.9-rc3.  Do you want me to resend
the series anyway or is there anything else needed at this point?

Maybe one thing that wasn't completely clear in v1 was whether
patch 2/4 was the right approach.  I've explained the reason
behind it but didn't get a final reply from Russell[1].

Best wishes,
Guillaume


[1] https://lore.kernel.org/lkml/46fa1159-fcd6-b528-b8e8-2fba048236b2@collabora.com/


> diff --git a/arch/arm/mach-exynos/exynos.c b/arch/arm/mach-exynos/exynos.c
> index 36c37444485a..a96f3353a0c1 100644
> --- a/arch/arm/mach-exynos/exynos.c
> +++ b/arch/arm/mach-exynos/exynos.c
> @@ -193,8 +193,8 @@ static void __init exynos_dt_fixup(void)
>  }
>  
>  DT_MACHINE_START(EXYNOS_DT, "Samsung Exynos (Flattened Device Tree)")
> -	.l2c_aux_val	= 0x3c400000,
> -	.l2c_aux_mask	= 0xc20fffff,
> +	.l2c_aux_val	= 0x38400000,
> +	.l2c_aux_mask	= 0xc60fffff,
>  	.smp		= smp_ops(exynos_smp_ops),
>  	.map_io		= exynos_init_io,
>  	.init_early	= exynos_firmware_init,
>