[U-Boot] [PATCH v4] Fix board init code to use a valid C runtime environment

[Alexey Brodkin <Alexey.Brodkin@synopsys.com>]

Hi Albert,

On Sun, 2015-11-15 at 19:25 +0100, Albert ARIBAUD wrote:
> board_init_f_mem() alters the C runtime environment's
> stack it ls actually already using. This is not a valid
> C runtime environment.
> 
> Split board_init_f_mem into C functions which do not
> alter their own stack and therefore run in a valid C
> runtime environment.
> 
> Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
> ---
> Cc:ing custodians for all architectures which this
> patch affects.
> 
> This patch has been build-tested for all there
> architectures, and run-tested on ARM OpenRD Client.
> 
> For NIOS2, this patch contains all manual v1 and v2
> fixes by Thomas.
> 
> For x86, this patch contains all manual v2 fixes by Bin.
> 
> Changes in v4:
> - Add comments on reserving GD at the lowest location
> - Add comments on post-incrementing base for each "chunk"
> 
> Changes in v3:
> - Rebase after commit 9ac4fc82
> - Simplify malloc conditional as per commit 9ac4fc82
> - Fix NIOS2 return value register (r2, not r4)
> - Fix x86 subl argument inversion
> - Group allocations in a single function
> - Group initializations in a single function
> 
> Changes in v2:
> - Fix all checkpatch issues
> - Fix board_init_f_malloc prototype mismatch
> - Fix board_init_[f_]xxx typo in NIOS2
> - Fix aarch64 asm 'sub' syntax error
> 
>  arch/arc/lib/start.S            |  12 +++--
>  arch/arm/lib/crt0.S             |   6 ++-
>  arch/arm/lib/crt0_64.S          |   6 ++-
>  arch/microblaze/cpu/start.S     |   4 +-
>  arch/nios2/cpu/start.S          |  13 +++--
>  arch/powerpc/cpu/ppc4xx/start.S |  10 ++--
>  arch/x86/cpu/start.S            |   5 +-
>  arch/x86/lib/fsp/fsp_common.c   |   4 +-
>  common/init/board_init.c        | 108 +++++++++++++++++++++++++++++++++++-----
>  include/common.h                |  33 +++++-------
>  10 files changed, 144 insertions(+), 57 deletions(-)
> 
> diff --git a/arch/arc/lib/start.S b/arch/arc/lib/start.S
> index 26a5934..2a99193 100644
> --- a/arch/arc/lib/start.S
> +++ b/arch/arc/lib/start.S
> @@ -54,14 +54,16 @@ ENTRY(_start)
>  	mov	%sp, CONFIG_SYS_INIT_SP_ADDR
>  	mov	%fp, %sp
>  
> -	/* Allocate and zero GD, update SP */
> -	mov	%r0, %sp
> -	bl	board_init_f_mem
> -
> +	/* Get reserved area size, update SP and FP */
> +	bl	board_init_f_get_reserve_size
>  	/* Update stack- and frame-pointers */

I think we don't need to mention SP/FP update in comments twice here.
I.e. either strip ", update SP and FP" from your introduced comment or
which I really like more remove following line with comment entirely:
---------->8----------
	/* Update stack- and frame-pointers */
---------->8----------

Not sure if this tiny nitpick worth respinning thought.

Otherwise build and run tested on free nSIM,
see "Running U-Boot on ARC in Free nSIM" section in
http://www.denx.de/wiki/U-Boot/ARCNotes if of any interest how to do it
yourself.

Feel free to add
---------->8----------
Acked-by: Alexey Brodkin <abrodkin@synopsys.com>
---------->8----------

-Alexey