[U-Boot] [PATCH 1/5] ARM: socfpga: Add boot trampoline for Arria10

[See, Chin Liang]

Hi Marek,

On Sun, 2018-04-15 at 15:37 +0200, Marek Vasut wrote:
> The Arria10 uses slightly different boot image header than the Gen5
> SoCs,
> in particular the header itself contains an offset from the start of
> the
> header to which the Arria10 jumps. This offset must not be negative,
> yet
> the header is placed at offset 0x40 of the bootable binary.
> Therefore, to
> jump into U-Boot, add a trampoline just past the Arria10 boot header
> and
> point to this trampoline at fixed offset from the header generated
> using
> the mkimage -T socfpgaimage_v1 . Note that it is not needed to jump
> back
> to offset 0x0 of the image, it is possible to jump directly at the
> reset
> label and save processing two instructions.
> 
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Dinh Nguyen <dinguyen at kernel.org>
> Cc: Chin Liang See <chin.liang.see at intel.com>
> ---
>  arch/arm/mach-socfpga/include/mach/boot0.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/mach-socfpga/include/mach/boot0.h
> b/arch/arm/mach-socfpga/include/mach/boot0.h
> index d6b9435d33..06bbe27d2c 100644
> --- a/arch/arm/mach-socfpga/include/mach/boot0.h
> +++ b/arch/arm/mach-socfpga/include/mach/boot0.h
> @@ -18,10 +18,10 @@ _start:
>  	.word	0xcafec0d3;	/* Checksum, zero-pad */
>  	nop;
>  
> -	b reset;		/* SoCFPGA jumps here */
> -	nop;
> +	b reset;		/* SoCFPGA Gen5 jumps here */
>  	nop;
>  	nop;
> +	b reset;		/* SoCFPGA Gen10 trampoline */

Our mkpimage tools from SOCEDS is using 0x14 as offset. Wonder can we
standardize that by using 0x14 instead of proposed 0x18 in this patch?

Thanks
Chin Liang

>  #endif
>  
>  #endif /* __BOOT0_H */