[U-Boot] [PATCH] arm: Add support for semihosting for armv8 fastmodel targets.

[Albert ARIBAUD]

Hi Darwin,

On Wed, 12 Mar 2014 09:04:01 -0700, Darwin Rambo <drambo at broadcom.com>
wrote:

> The reason for this change is to be able to use the ARM Trusted Firmware
> (ATF) to load the various ATF images, plus u-boot, which can then load
> the kernel/ramdisk/dtb with calls to an external host from a standard
> fastmodel armv8 board file using semihosting, and then launch the kernel
> without a bootwrapper. This gives us a more realistic boot sequence.
> 
> Rather than create a new armv8 board similar to armltd/vexpress64, add
> semihosting calls to the existing one, enabled with CONFIG_SEMIHOSTING.
> Also add a new board config file vexpress_aemv8a_semi.h. This change is
> tested and works on the ARM foundation model.
> 
> Support for armv7 in fastmodel is less useful due to the wide range of
> available silicon but this change contains an untested armv7 placeholder
> if desired.
> 
> The level of semihosting support is minimal, restricted to just what it
> takes to load images to memory. If more semihosting functionality is
> required, such as file seek, outputting strings, reading characters, etc,
> then it can be easily added later.
> 
> Signed-off-by: Darwin Rambo <drambo at broadcom.com>
> ---

If you're only adding semihosting to vexpress_aemv8a, not creating a
new board, then why add a new header file? Can you not just reuse
orextend the existing header file, and make the new entry in
boards.cfg define option CONFIG_SEMIHOSTING instead?  

> diff --git a/board/armltd/vexpress64/vexpress64.c b/board/armltd/vexpress64/vexpress64.c
> index 2ec3bc9..9b64f71 100644
> --- a/board/armltd/vexpress64/vexpress64.c
> +++ b/board/armltd/vexpress64/vexpress64.c

> @@ -31,11 +35,6 @@ int dram_init(void)
>  	return 0;
>  }
>  
> -int timer_init(void)
> -{
> -	return 0;
> -}
> -

This removal does not seem to be described in the commit summary.

Amicalement,
-- 
Albert.