Re: [PATCH 7/9] ARM: tegra: enable cache via TF

[Russell King - ARM Linux <linux-I+IVW8TIWO2tmTQ+vhA3Yw@public.gmane.org>]

On Thu, Jul 20, 2017 at 02:29:25AM +0200, Michał Mirosław wrote:
> diff --git a/arch/arm/mach-tegra/reset-handler.S b/arch/arm/mach-tegra/reset-handler.S
> index 805f306fa6f7..aae7f5961563 100644
> --- a/arch/arm/mach-tegra/reset-handler.S
> +++ b/arch/arm/mach-tegra/reset-handler.S
> @@ -78,8 +78,20 @@ ENTRY(tegra_resume)
>  	orr	r1, r1, #1
>  	str	r1, [r0]
>  #endif
> +#ifdef CONFIG_TRUSTED_FOUNDATIONS
> +	adr	r3, __tegra_smc_stack
> +	stmia	r3, {r4-r12, sp, lr}
>  
> -#ifdef CONFIG_CACHE_L2X0
> +	mov	r0, #3	// local wake
> +	mov	r3, #0
> +	mov	r4, #0
> +	dsb
> +	.arch_extension	sec
> +	smc	#0
> +
> +	adr	r3, __tegra_smc_stack
> +	ldmia	r3, {r4-r12, sp, pc}

You don't want to jump to the 'lr' value previously stacked here.  I
also wonder whether you need all this stacking, or whether you're
just doing it because you don't know whether its necessary.  From
what I can see, the only register that this code cares about is r8,
although it would be wise to place a comment in the code if the smc
call corrupts the other registers.

-- 
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