powerpc/mm: Define platform default caches related flags

Cache related flags like _PAGE_COHERENT and _PAGE_WRITETHRU
are defined on most platforms. The platforms not defining
them don't define any alternative. So we can give them a NUL
value directly for those platforms directly.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Christophe Leroy 2018-10-09 13:52:14 +00:00 committed by Michael Ellerman
parent a0da4bc166
commit cbcbbf4afd
3 changed files with 7 additions and 11 deletions

View file

@ -53,6 +53,9 @@
/* No page size encoding in the linux PTE */
#define _PAGE_PSIZE 0
/* cache related flags non existing on 40x */
#define _PAGE_COHERENT 0
#define _PAGE_KERNEL_RO 0
#define _PAGE_KERNEL_ROX _PAGE_EXEC
#define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW | _PAGE_HWWRITE)

View file

@ -46,6 +46,10 @@
#define _PAGE_NA 0x0200 /* Supervisor NA, User no access */
#define _PAGE_RO 0x0600 /* Supervisor RO, User no access */
/* cache related flags non existing on 8xx */
#define _PAGE_COHERENT 0
#define _PAGE_WRITETHRU 0
#define _PAGE_KERNEL_RO (_PAGE_PRIVILEGED | _PAGE_RO)
#define _PAGE_KERNEL_ROX (_PAGE_PRIVILEGED | _PAGE_RO | _PAGE_EXEC)
#define _PAGE_KERNEL_RW (_PAGE_PRIVILEGED | _PAGE_DIRTY)

View file

@ -1,17 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 */
/* Included from asm/pgtable-*.h only ! */
/*
* Some bits are only used on some cpu families... Make sure that all
* the undefined gets a sensible default
*/
#ifndef _PAGE_COHERENT
#define _PAGE_COHERENT 0
#endif
#ifndef _PAGE_WRITETHRU
#define _PAGE_WRITETHRU 0
#endif
/* Location of the PFN in the PTE. Most 32-bit platforms use the same
* as _PAGE_SHIFT here (ie, naturally aligned).
* Platform who don't just pre-define the value so we don't override it here