Subject: Re: [PATCH v6 2/6] powerpc/book3s64/radix: Add H_RPT_INVALIDATE pgsize encodings to mmu_psize_def

From: David Gibson <[email-masked]>
Date: Tue, 23 Mar 2021 12:24:36 +1100

On Thu, Mar 11, 2021 at 02:09:35PM +0530, Bharata B Rao wrote:
> Add a field to mmu_psize_def to store the page size encodings
> of H_RPT_INVALIDATE hcall. Initialize this while scanning the radix
> AP encodings. This will be used when invalidating with required
> page size encoding in the hcall.
> 
> Signed-off-by: Bharata B Rao <[email-masked]>

Having the table be the source of truth and implementing
psize_to_rpti_pgsize() in terms of it would be nicer.  But... I guess
you can't really do that, because you're dynamically initializing the
table from the device tree, but the device tree doesn't include the
RPTI encodings.  Oh well.

Reveiwed-by: David Gibson <[email-masked]>

> ---
>  arch/powerpc/include/asm/book3s/64/mmu.h | 1 +
>  arch/powerpc/mm/book3s64/radix_pgtable.c | 5 +++++
>  2 files changed, 6 insertions(+)
> 
> diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
> index eace8c3f7b0a..c02f42d1031e 100644
> --- a/arch/powerpc/include/asm/book3s/64/mmu.h
> +++ b/arch/powerpc/include/asm/book3s/64/mmu.h
> @@ -19,6 +19,7 @@ struct mmu_psize_def {
>  	int		penc[MMU_PAGE_COUNT];	/* HPTE encoding */
>  	unsigned int	tlbiel;	/* tlbiel supported for that page size */
>  	unsigned long	avpnm;	/* bits to mask out in AVPN in the HPTE */
> +	unsigned long   h_rpt_pgsize; /* H_RPT_INVALIDATE page size encoding */
>  	union {
>  		unsigned long	sllp;	/* SLB L||LP (exact mask to use in slbmte) */
>  		unsigned long ap;	/* Ap encoding used by PowerISA 3.0 */
> diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
> index 98f0b243c1ab..1b749899016b 100644
> --- a/arch/powerpc/mm/book3s64/radix_pgtable.c
> +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
> @@ -486,6 +486,7 @@ static int __init radix_dt_scan_page_sizes(unsigned long node,
>  		def = &mmu_psize_defs[idx];
>  		def->shift = shift;
>  		def->ap  = ap;
> +		def->h_rpt_pgsize = psize_to_rpti_pgsize(idx);
>  	}
>  
>  	/* needed ? */
> @@ -560,9 +561,13 @@ void __init radix__early_init_devtree(void)
>  		 */
>  		mmu_psize_defs[MMU_PAGE_4K].shift = 12;
>  		mmu_psize_defs[MMU_PAGE_4K].ap = 0x0;
> +		mmu_psize_defs[MMU_PAGE_4K].h_rpt_pgsize =
> +			psize_to_rpti_pgsize(MMU_PAGE_4K);
>  
>  		mmu_psize_defs[MMU_PAGE_64K].shift = 16;
>  		mmu_psize_defs[MMU_PAGE_64K].ap = 0x5;
> +		mmu_psize_defs[MMU_PAGE_64K].h_rpt_pgsize =
> +			psize_to_rpti_pgsize(MMU_PAGE_64K);
>  	}
>  
>  	/*

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
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