diff options
| author | Christophe Leroy <christophe.leroy@c-s.fr> | 2016-12-07 08:47:28 +0100 |
|---|---|---|
| committer | Scott Wood <oss@buserror.net> | 2016-12-09 22:49:07 -0600 |
| commit | 4b91428699477532ab1255c2dd5819713e9e8985 (patch) | |
| tree | fdfb7370974a1ec518d40cc4b145c02886de831e /arch/powerpc/include/asm/nohash/pgtable.h | |
| parent | 03bb2d65900c87a6cc860310b4d598c68fb83393 (diff) | |
powerpc/8xx: Implement support of hugepages
8xx uses a two level page table with two different linux page size
support (4k and 16k). 8xx also support two different hugepage sizes
512k and 8M. In order to support them on linux we define two different
page table layout.
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
For 512K hugepage size a pgd entry have the below format
[<hugepte address >0101] . The hugepte table allocated will contain 8
entries pointing to 512K huge pte in 4k pages mode and 64 entries in
16k pages mode.
For 8M in 16k mode, a pgd entry have the below format
[<hugepte address >1101] . The hugepte table allocated will contain 8
entries pointing to 8M huge pte.
For 8M in 4k mode, multiple pgd entries point to the same hugepte
address and pgd entry will have the below format
[<hugepte address>1101]. The hugepte table allocated will only have one
entry.
For the time being, we do not support CPU15 ERRATA when HUGETLB is
selected
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> (v3, for the generic bits)
Signed-off-by: Scott Wood <oss@buserror.net>
Diffstat (limited to 'arch/powerpc/include/asm/nohash/pgtable.h')
| -rw-r--r-- | arch/powerpc/include/asm/nohash/pgtable.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h index 1263c22d60d8..172849727054 100644 --- a/arch/powerpc/include/asm/nohash/pgtable.h +++ b/arch/powerpc/include/asm/nohash/pgtable.h @@ -226,7 +226,11 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, #ifdef CONFIG_HUGETLB_PAGE static inline int hugepd_ok(hugepd_t hpd) { +#ifdef CONFIG_PPC_8xx + return ((hpd.pd & 0x4) != 0); +#else return (hpd.pd > 0); +#endif } static inline int pmd_huge(pmd_t pmd) |