From c341a108a58100b4d0774ddb1dacbd67dfa749b3 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 11 Mar 2019 08:30:32 +0000 Subject: [PATCH] powerpc/8xx: Only define APG0 and APG1 Since the 8xx implements hardware page table walk assistance, the PGD entries always point to a 4k aligned page, so the 2 upper bits of the APG are not clobbered anymore and remain 0. Therefore only APG0 and APG1 are used and need a definition. We set the other APG to the lowest permission level. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/nohash/32/mmu-8xx.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/include/asm/nohash/32/mmu-8xx.h b/arch/powerpc/include/asm/nohash/32/mmu-8xx.h index 0a1a3fc54e54..fc5a653d5dd2 100644 --- a/arch/powerpc/include/asm/nohash/32/mmu-8xx.h +++ b/arch/powerpc/include/asm/nohash/32/mmu-8xx.h @@ -35,11 +35,11 @@ * Then we use the APG to say whether accesses are according to Page rules or * "all Supervisor" rules (Access to all) * Therefore, we define 2 APG groups. lsb is _PMD_USER - * 0 => No user => 01 (all accesses performed according to page definition) + * 0 => Kernel => 01 (all accesses performed according to page definition) * 1 => User => 00 (all accesses performed as supervisor iaw page definition) - * We define all 16 groups so that all other bits of APG can take any value + * 2-16 => NA => 11 (all accesses performed as user iaw page definition) */ -#define MI_APG_INIT 0x44444444 +#define MI_APG_INIT 0x4fffffff /* The effective page number register. When read, contains the information * about the last instruction TLB miss. When MI_RPN is written, bits in @@ -108,11 +108,11 @@ * Then we use the APG to say whether accesses are according to Page rules or * "all Supervisor" rules (Access to all) * Therefore, we define 2 APG groups. lsb is _PMD_USER - * 0 => No user => 01 (all accesses performed according to page definition) + * 0 => Kernel => 01 (all accesses performed according to page definition) * 1 => User => 00 (all accesses performed as supervisor iaw page definition) - * We define all 16 groups so that all other bits of APG can take any value + * 2-16 => NA => 11 (all accesses performed as user iaw page definition) */ -#define MD_APG_INIT 0x44444444 +#define MD_APG_INIT 0x4fffffff /* The effective page number register. When read, contains the information * about the last instruction TLB miss. When MD_RPN is written, bits in -- 2.30.2