From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wolfgang Denk <wd@denx.de>
Date: Fri, 01 Dec 2006 15:31:52 +0100
Subject: [U-Boot-Users] [PATCH 00/07 v2]: Add mpc7448hpc2 (Taiga) board
	support
In-Reply-To: Your message of "01 Dec 2006 16:09:27 +0800."
	<1164960567.6742.25.camel@localhost.localdomain> 
Message-ID: <20061201143152.9F8E4352621@atlas.denx.de>
List-Id: <u-boot.lists.denx.de>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
To: u-boot@lists.denx.de

In message <1164960567.6742.25.camel@localhost.localdomain> you wrote:
> 
> index d92f142..8a4d141 100644
> --- a/lib_ppc/extable.c
> +++ b/lib_ppc/extable.c
> @@ -50,15 +50,29 @@ search_one_table(const struct exception_
>  		 const struct exception_table_entry *last,
>  		 unsigned long value)
>  {
> +	DECLARE_GLOBAL_DATA_PTR;
> +
>  	while (first <= last) {
>  		const struct exception_table_entry *mid;
>  		long diff;
>  
>  		mid = (last - first) / 2 + first;
> -		diff = mid->insn - value;
> -		if (diff == 0)
> -			return mid->fixup;
> -		else if (diff < 0)
> +		if (mid > CFG_MONITOR_BASE) { 
> +		/* exception occurs in FLASH, before u-boot relocation.
> +		 * No relocation offset is needed. 
> +		 */
> +			diff = mid->insn - value;
> +			if (diff == 0)
> +				return mid->fixup;
> +		} else {
> +		/* exception occurs in RAM, after u-boot relocation. 
> +		 * A relocation offset should be added.
> +		 */
> +			diff = (mid->insn + gd->reloc_off) - value;
> +			if (diff == 0)
> +				return (mid->fixup + gd->reloc_off);
> +		}
> +		if (diff < 0)
>  			first = mid+1;
>  		else
>  			last = mid-1;

The problem I see  with  this  code  is  that  it  is  based  on  the
assumption  that  CFG_MONITOR_BASE  is  greater than any RAM address.
While this is always true so far, I would rather not rely on this.

And I still don't understand why this change is necessary, and/or  if
this  is  the right fix. If a fix is needed, then probably the values
of "value" is wrong in the first place, so the fix should be  in  the
calling routine.

Also please note that the DECLARE_GLOBAL_DATA_PTR declaration must be
placed outside the function, i. e. on file scope.



Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Wisdom is one of the few things that looks bigger the further away it
is.                               - Terry Pratchett, _Witches Abroad_