[U-Boot] [PATCH 1/2] MX28: Drop the cp15 reconfiguration from SPL

[Stefano Babic]

On 06/08/2012 23:34, Marek Vasut wrote:
> The SPL doesn't need the CP15 reconfiguration, as that's what the
> BootROM does for us already. Moreover, when the CP15 is reconfigured
> and the code returns control to BootROM, the USB boot works no more.
> 
> Remove the code and allow [1] to work properly as well.
> 
> [1] http://git.bfuser.eu/?p=marex/mxsldr.git;a=summary
> 
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Stefano Babic <sbabic at denx.de>
> Cc: Fabio Estevam <fabio.estevam at freescale.com>
> ---
>  arch/arm/cpu/arm926ejs/mx28/start.S |   42 -----------------------------------
>  1 file changed, 42 deletions(-)
> 
> diff --git a/arch/arm/cpu/arm926ejs/mx28/start.S b/arch/arm/cpu/arm926ejs/mx28/start.S
> index e572b78..7ccd337 100644
> --- a/arch/arm/cpu/arm926ejs/mx28/start.S
> +++ b/arch/arm/cpu/arm926ejs/mx28/start.S
> @@ -180,14 +180,6 @@ _reset:
>  	orr	r0,r0,#0xd3
>  	msr	cpsr,r0
>  
> -	/*
> -	 * we do sys-critical inits only at reboot,
> -	 * not when booting from ram!
> -	 */
> -#ifndef CONFIG_SKIP_LOWLEVEL_INIT
> -	bl	cpu_init_crit
> -#endif
> -
>  	bl	board_init_ll
>  
>  	/*
> @@ -207,40 +199,6 @@ _reset:
>  	pop	{r0-r12,r14}
>  	bx	lr
>  
> -/*
> - *************************************************************************
> - *
> - * CPU_init_critical registers
> - *
> - * setup important registers
> - * setup memory timing
> - *
> - *************************************************************************
> - */
> -#ifndef CONFIG_SKIP_LOWLEVEL_INIT
> -cpu_init_crit:
> -	/*
> -	 * flush v4 I/D caches
> -	 */
> -	mov	r0, #0
> -	mcr	p15, 0, r0, c7, c7, 0	/* flush v3/v4 cache */
> -	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
> -
> -	/*
> -	 * disable MMU stuff and caches
> -	 */
> -	mrc	p15, 0, r0, c1, c0, 0
> -	bic	r0, r0, #0x00002300	/* clear bits 13, 9:8 (--V- --RS) */
> -	bic	r0, r0, #0x00000087	/* clear bits 7, 2:0 (B--- -CAM) */
> -	orr	r0, r0, #0x00000002	/* set bit 2 (A) Align */
> -	orr	r0, r0, #0x00001000	/* set bit 12 (I) I-Cache */
> -	mcr	p15, 0, r0, c1, c0, 0
> -
> -	mov	pc, lr		/* back to my caller */
> -
> -	.align	5
> -#endif /* CONFIG_SKIP_LOWLEVEL_INIT */
> -
>  _hang:
>  	ldr	sp, _TEXT_BASE			/* switch to abort stack */
>  1:
> 

Acked-by: Stefano Babic <sbabic at denx.de>

Best regards,
Stefano Babic

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