From cadbfd01468663e8b9f9518a58ef67398a20d06b Mon Sep 17 00:00:00 2001 From: LEROY Christophe Date: Mon, 19 Jan 2015 17:04:44 +0100 Subject: [PATCH] powerpc/8xx: use _PAGE_RO instead of _PAGE_RW On powerpc 8xx, in TLB entries, 0x400 bit is set to 1 for read-only pages and is set to 0 for RW pages. So we should use _PAGE_RO instead of _PAGE_RW Signed-off-by: Christophe Leroy Signed-off-by: Scott Wood --- arch/powerpc/include/asm/pgtable-ppc32.h | 11 +++++------ arch/powerpc/include/asm/pte-8xx.h | 9 ++++----- arch/powerpc/kernel/head_8xx.S | 3 --- 3 files changed, 9 insertions(+), 14 deletions(-) diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h index 62a3e49a9a14..9cde3c1522e3 100644 --- a/arch/powerpc/include/asm/pgtable-ppc32.h +++ b/arch/powerpc/include/asm/pgtable-ppc32.h @@ -178,12 +178,11 @@ static inline unsigned long pte_update(pte_t *p, andc %1,%0,%5\n\ or %1,%1,%6\n\ /* 0x200 == Extended encoding, bit 22 */ \ - /* Bit 22 has to be 1 if neither _PAGE_USER nor _PAGE_RW are set */ \ - rlwimi %1,%1,32-2,0x200\n /* get _PAGE_USER */ \ - rlwinm %3,%1,32-1,0x200\n /* get _PAGE_RW */ \ - or %1,%3,%1\n\ - xori %1,%1,0x200\n" -" stwcx. %1,0,%4\n\ + /* Bit 22 has to be 1 when _PAGE_USER is unset and _PAGE_RO is set */ \ + rlwimi %1,%1,32-1,0x200\n /* get _PAGE_RO */ \ + rlwinm %3,%1,32-2,0x200\n /* get _PAGE_USER */ \ + andc %1,%1,%3\n\ + stwcx. %1,0,%4\n\ bne- 1b" : "=&r" (old), "=&r" (tmp), "=m" (*p), "=&r" (tmp2) : "r" (p), "r" (clr), "r" (set), "m" (*p) diff --git a/arch/powerpc/include/asm/pte-8xx.h b/arch/powerpc/include/asm/pte-8xx.h index daa4616e61c4..eb6edb44f140 100644 --- a/arch/powerpc/include/asm/pte-8xx.h +++ b/arch/powerpc/include/asm/pte-8xx.h @@ -46,9 +46,9 @@ * require a TLB exception handler change. It is assumed unused bits * are always zero. */ -#define _PAGE_RW 0x0400 /* lsb PP bits, inverted in HW */ +#define _PAGE_RO 0x0400 /* lsb PP bits */ #define _PAGE_USER 0x0800 /* msb PP bits */ -/* set when neither _PAGE_USER nor _PAGE_RW are set */ +/* set when _PAGE_USER is unset and _PAGE_RO is set */ #define _PAGE_KNLRO 0x0200 #define _PMD_PRESENT 0x0001 @@ -62,9 +62,8 @@ #define PTE_ATOMIC_UPDATES 1 /* We need to add _PAGE_SHARED to kernel pages */ -#define _PAGE_KERNEL_RO (_PAGE_SHARED | _PAGE_KNLRO) -#define _PAGE_KERNEL_ROX (_PAGE_EXEC | _PAGE_KNLRO) -#define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW | _PAGE_HWWRITE) +#define _PAGE_KERNEL_RO (_PAGE_SHARED | _PAGE_RO | _PAGE_KNLRO) +#define _PAGE_KERNEL_ROX (_PAGE_EXEC | _PAGE_RO | _PAGE_KNLRO) #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_PTE_8xx_H */ diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index d99aac0d69f1..65492d043964 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -441,9 +441,6 @@ DataStoreTLBMiss: and r11, r11, r10 rlwimi r10, r11, 0, _PAGE_PRESENT #endif - /* invert RW */ - xori r10, r10, _PAGE_RW - /* The Linux PTE won't go exactly into the MMU TLB. * Software indicator bits 22 and 28 must be clear. * Software indicator bits 24, 25, 26, and 27 must be -- 2.20.1