Re: [Qemu-devel] [PATCH 7/8] PPC: booke206: Check for min/max TLB entry size

[Scott Wood]

On 01/20/2012 10:15 PM, Alexander Graf wrote:
> @@ -4273,6 +4274,16 @@ void helper_booke206_tlbwe(void)
>          tlb->mas1 &= ~MAS1_IPROT;
>      }
>  
> +    /* check that we support the targeted size */
> +    size_tlb = (tlb->mas1 & MAS1_TSIZE_MASK) >> MAS1_TSIZE_SHIFT;
> +    size_ps = booke206_tlbnps(env, tlbn);
> +    if ((tlb->mas1 & MAS1_VALID) && (tlbncfg & TLBnCFG_AVAIL) &&
> +        !(size_ps & (1 << size_tlb))) {
> +        helper_raise_exception_err(POWERPC_EXCP_PROGRAM,
> +                                   POWERPC_EXCP_INVAL |
> +                                   POWERPC_EXCP_INVAL_INVAL);
> +    }
> +
>      if (booke206_tlb_to_page_size(env, tlb) == TARGET_PAGE_SIZE) {
>          tlb_flush_page(env, tlb->mas2 & MAS2_EPN_MASK);
>      } else {

For tlb0 on e500 and derivatives, tsize is explicitly documented as
ignored.  Software may rely on this.

-Scott