Subject: Re: [PATCH] powerpc: Add support for early tlbilx opcode

From: Michael Ellerman <[email-masked]>
Date: Tue, 07 Apr 2009 16:43:41 +1000

On Tue, 2009-04-07 at 01:13 -0500, Kumar Gala wrote:
> During the ISA 2.06 development the opcode for tlbilx changed and some
> early implementations used to old opcode.  Add support for a MMU_FTR
> fixup to deal with this.
> 
> Signed-off-by: Kumar Gala <[email-masked]>
> ---
>  arch/powerpc/include/asm/mmu.h        |    6 ++++++
>  arch/powerpc/include/asm/ppc-opcode.h |   11 ++++++++++-
>  arch/powerpc/kernel/cputable.c        |    2 +-
>  arch/powerpc/mm/tlb_nohash_low.S      |   14 +++++++++++++-
>  4 files changed, 30 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h
> index cbf1543..86d2366 100644
> --- a/arch/powerpc/include/asm/mmu.h
> +++ b/arch/powerpc/include/asm/mmu.h
> @@ -52,6 +52,12 @@
>   */
>  #define MMU_FTR_NEED_DTLB_SW_LRU	ASM_CONST(0x00200000)
>  
> +/* This indicates that the processor uses the wrong opcode for tlbilx
> + * instructions.  During the ISA 2.06 development the opcode for tlbilx
> + * changed and some early implementations used to old opcode
> + */
> +#define MMU_FTR_TLBILX_EARLY_OPCODE	ASM_CONST(0x00400000)

You're actually going to ship those parts? :)

It seems a pity to use up a feature bit.

cheers

-- 
Michael Ellerman
OzLabs, IBM Australia Development Lab

wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)

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we borrow it from our children. - S.M.A.R.T Person