Subject: Re: [PATCH 0/8] Fix 8xx MMU/TLB

From: Scott Wood <[email-masked]>
Date: Fri, 30 Oct 2009 12:16:07 -0500

On Sat, Oct 17, 2009 at 02:01:38PM +0200, Joakim Tjernlund wrote:
> +     mfspr r10, SPRN_SRR0
>       DO_8xx_CPU6(0x3780, r3)
>       mtspr SPRN_MD_EPN, r10
>       mfspr r11, SPRN_M_TWB	/* Get level 1 table entry address */
> -     lwz   r11, 0(r11)	/* Get the level 1 entry */
> +     cmplwi      cr0, r11, 0x0800
> +     blt-  3f		/* Branch if user space */
> +     lis   r11, swapper_pg_dir@h
> +     ori   r11, r11, swapper_pg_dir@l
> +     rlwimi      r11, r11, 0, 2, 19

That rlwimi is a no-op -- I think you meant to use a different register
here?

> +3:   lwz   r11, 0(r11)	/* Get the level 1 entry */
>       DO_8xx_CPU6(0x3b80, r3)
>       mtspr SPRN_MD_TWC, r11	/* Load pte table base address */
>       mfspr r11, SPRN_MD_TWC	/* ....and get the pte address */
>       lwz   r11, 0(r11)	/* Get the pte */
>       /* concat physical page address(r11) and page offset(r10) */
>       rlwimi      r11, r10, 0, 20, 31

But r10 here contains SRR0 from above, and this is a data TLB error.

-Scott