Subject: Re: [PATCH 6/6] powerpc/8xx: implementation of huge pages

From: "Aneesh Kumar K.V" <[email-masked]>
Date: Sun, 14 Aug 2016 19:55:30 +0530

Christophe Leroy <[email-masked]> writes:

> The 8xx has 512k and 8M pages. This patch implements hugepages using
> those sizes.
>
> On the 8xx, the size of pages is in the PGD entry,
> using PS field (bits 28-29):
> 00 : Small pages (4k or 16k)
> 01 : 512k pages
> 10 : reserved
> 11 : 8M pages
>
> The implementation uses a mix of what is used on BOOKS and BOOKE,
> as 512k pages are in HUGEPTE tables while for 8M pages we have
> several PGD entries pointing on a leaf HUGEPTE entry
>
> For the time being, we do not support CPU15 ERRATA if HUGETLB is
> selected

Can you also document here the format for linux page table with different
huge page size. ?

>
> Signed-off-by: Christophe Leroy <[email-masked]>