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Subject: Re: [PATCH 1/6] 8xx: DTLB Error must check for more errors.
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
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Date: Fri, 09 Oct 2009 07:48:18 +1100
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Cc: Scott Wood <scottwood@freescale.com>,
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On Thu, 2009-10-08 at 15:24 +0200, Joakim Tjernlund wrote:
> DataTLBError currently does:
>  if ((err & 0x02000000) == 0)
>     DSI();
> This won't handle a store with no valid translation.
> Change this to
>  if ((err & 0x48000000) != 0)
>     DSI();
> that is, branch to DSI if either !permission or
> !translation.
> ---

As I said earlier, I don't think this is necessary, just get rid of the
whole bunch of code in DataTLBError :-)

Ben.

>  arch/powerpc/kernel/head_8xx.S |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
> index 52ff8c5..118bb05 100644
> --- a/arch/powerpc/kernel/head_8xx.S
> +++ b/arch/powerpc/kernel/head_8xx.S
> @@ -472,8 +472,8 @@ DataTLBError:
>  	/* First, make sure this was a store operation.
>  	*/
>  	mfspr	r10, SPRN_DSISR
> -	andis.	r11, r10, 0x0200	/* If set, indicates store op */
> -	beq	2f
> +	andis.	r11, r10, 0x4800 /* no translation, no permission. */
> +	bne	2f	/* branch if either is set */
>  
>  	/* The EA of a data TLB miss is automatically stored in the MD_EPN
>  	 * register.  The EA of a data TLB error is automatically stored in