[PATCH 03/12] Add pre-bootloader (pbl) image support

[Sascha Hauer]

On Mon, Jul 30, 2012 at 12:02:36PM +0200, Jean-Christophe PLAGNIOL-VILLARD wrote:
> +
> +	/* Setup the stack */
> +	r = STACK_BASE + STACK_SIZE - 16;
> +	__asm__ __volatile__("mov sp, %0" : : "r"(r));
> +	/* clear bss */
> +	memset(__bss_start, 0, __bss_stop - __bss_start);
> +
> +	start_barebox();
> +}
> +#else
>  void __naked __section(.text_entry) start(void)
>  {
>  	barebox_arm_head();
>  }
> +#endif
>  
>  /*
>   * The actual reset vector. This code is position independent and usually
> @@ -73,6 +97,14 @@ void __naked __bare_init reset(void)
>  	board_init_lowlevel_return();
>  }
>  
> +#ifdef __PBL__
> +void barebox_pbl(uint32_t offset)
> +{
> +}
> +#else
> +void barebox_pbl(uint32_t offset) {}
> +#endif
> +
>  /*
>   * Board code can jump here by either returning from board_init_lowlevel
>   * or by calling this function directly.
> @@ -105,8 +137,11 @@ void __naked __section(.text_ll_return) board_init_lowlevel_return(void)
>  	/* flush I-cache before jumping to the copied binary */
>  	__asm__ __volatile__("mcr p15, 0, %0, c7, c5, 0" : : "r" (0));
>  
> -	/* call start_barebox with its absolute address */
> -	r = (unsigned int)&start_barebox;
> -	__asm__ __volatile__("mov pc, %0" : : "r"(r));
> +	if (IS_ENABLED(CONFIG_PBL_IMAGE)) {
> +		barebox_pbl(offset);

The pbl should be called at it's absolute address, not at it's relative
address. This makes sure that the pbl code is running in a completely
valid C environment.

I fixed that before applying

Sascha

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