Other arches have ioremap_wt() to map IO areas write-through. Implement it on PPC as well in order to avoid drivers using __ioremap(_PAGE_WRITETHRU)
Signed-off-by: Christophe Leroy christophe.leroy@c-s.fr --- arch/powerpc/include/asm/io.h | 6 ++++++ arch/powerpc/mm/pgtable_32.c | 8 ++++++++ 2 files changed, 14 insertions(+)
diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h index e0331e754568..3380b5b22450 100644 --- a/arch/powerpc/include/asm/io.h +++ b/arch/powerpc/include/asm/io.h @@ -3,6 +3,9 @@ #ifdef __KERNEL__
#define ARCH_HAS_IOREMAP_WC +#ifdef CONFIG_PPC32 +#define ARCH_HAS_IOREMAP_WT +#endif
/* * This program is free software; you can redistribute it and/or @@ -746,6 +749,8 @@ static inline void iosync(void) * * * ioremap_wc enables write combining * + * * ioremap_wt enables write through + * * * iounmap undoes such a mapping and can be hooked * * * __ioremap_at (and the pending __iounmap_at) are low level functions to @@ -767,6 +772,7 @@ extern void __iomem *ioremap(phys_addr_t address, unsigned long size); extern void __iomem *ioremap_prot(phys_addr_t address, unsigned long size, unsigned long flags); extern void __iomem *ioremap_wc(phys_addr_t address, unsigned long size); +void __iomem *ioremap_wt(phys_addr_t address, unsigned long size); #define ioremap_nocache(addr, size) ioremap((addr), (size)) #define ioremap_uc(addr, size) ioremap((addr), (size)) #define ioremap_cache(addr, size) \ diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index 2bbc22384f78..b2e73e82f8fc 100644 --- a/arch/powerpc/mm/pgtable_32.c +++ b/arch/powerpc/mm/pgtable_32.c @@ -90,6 +90,14 @@ ioremap_wc(phys_addr_t addr, unsigned long size) EXPORT_SYMBOL(ioremap_wc);
void __iomem * +ioremap_wt(phys_addr_t addr, unsigned long size) +{ + return __ioremap_caller(addr, size, _PAGE_WRITETHRU, + __builtin_return_address(0)); +} +EXPORT_SYMBOL(ioremap_wt); + +void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags) { pte_t pte = __pte(flags);