[RFC PATCH v1 01/17] powerpc/32: Add ioremap_wt()
From: Christophe Leroy <hidden>
Date: 2018-09-05 12:36:57
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
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 <redacted> --- 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 120a49bfb9c6..528999738645 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) { /* writeable implies dirty for kernel addresses */
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2.13.3