ioremap_uc() is only meaningful on old x86-32 systems with the PAT extension, and on ia64 with its slightly unconventional ioremap() behavior, everywhere else this is the same as ioremap() anyway. Here, remove the ioremap_uc() definition in architecutures other than x86 and ia64. These architectures all have asm-generic/io.h included and will have the default ioremap_uc() definition which returns NULL. Note: This changes the existing behaviour and could break code calling ioremap_uc(). If any ARCH meets this breakage and really needs a specific ioremap_uc() for its own usage, one ioremap_uc() can be added in the ARCH. Link: https://lore.kernel.org/all/20191112105507.GA7122@xxxxxx/#t Signed-off-by: Baoquan He <bhe@xxxxxxxxxx> Acked-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> --- Documentation/driver-api/device-io.rst | 11 +++++++++-- arch/alpha/include/asm/io.h | 1 - arch/hexagon/include/asm/io.h | 3 --- arch/m68k/include/asm/kmap.h | 1 - arch/mips/include/asm/io.h | 1 - arch/parisc/include/asm/io.h | 2 -- arch/powerpc/include/asm/io.h | 1 - arch/sh/include/asm/io.h | 2 -- arch/sparc/include/asm/io_64.h | 1 - 9 files changed, 9 insertions(+), 14 deletions(-) diff --git a/Documentation/driver-api/device-io.rst b/Documentation/driver-api/device-io.rst index 4d2baac0311c..ec37faa37a37 100644 --- a/Documentation/driver-api/device-io.rst +++ b/Documentation/driver-api/device-io.rst @@ -408,9 +408,16 @@ functions for details on the CPU side of things. ioremap_uc() ------------ -ioremap_uc() behaves like ioremap() except that on the x86 architecture without +ioremap_uc() behaves like ioremap() except that on x86 architecture without 'PAT' mode, it marks memory as uncached even when the MTRR has designated -it as cacheable, see Documentation/x86/pat.rst. +it as cacheable, see Documentation/x86/pat.rst, and on ia64 which checks if +attributes don't match. + + +ioremap_uc() behaves like ioremap() except that on x86 and ia64 architectures. +X86 non-PAT system marks memory as uncached even when the MTRR has designated +it as cacheable in ioremap_uc()(see Documentation/x86/pat.rst). While ia64 +system firstly checks if attributes match ioremap_uc(), otherwise fails. Portable drivers should avoid the use of ioremap_uc(). diff --git a/arch/alpha/include/asm/io.h b/arch/alpha/include/asm/io.h index 7aeaf7c30a6f..076f0e4e7f1e 100644 --- a/arch/alpha/include/asm/io.h +++ b/arch/alpha/include/asm/io.h @@ -308,7 +308,6 @@ static inline void __iomem *ioremap(unsigned long port, unsigned long size) } #define ioremap_wc ioremap -#define ioremap_uc ioremap static inline void iounmap(volatile void __iomem *addr) { diff --git a/arch/hexagon/include/asm/io.h b/arch/hexagon/include/asm/io.h index dcd9cbbf5934..b9847472f25c 100644 --- a/arch/hexagon/include/asm/io.h +++ b/arch/hexagon/include/asm/io.h @@ -176,9 +176,6 @@ static inline void writel(u32 data, volatile void __iomem *addr) #define _PAGE_IOREMAP (_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \ (__HEXAGON_C_DEV << 6)) -#define ioremap_uc(addr, size) ioremap((addr), (size)) - - #define __raw_writel writel static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, diff --git a/arch/m68k/include/asm/kmap.h b/arch/m68k/include/asm/kmap.h index 4efb3efa593a..b778f015c917 100644 --- a/arch/m68k/include/asm/kmap.h +++ b/arch/m68k/include/asm/kmap.h @@ -25,7 +25,6 @@ static inline void __iomem *ioremap(unsigned long physaddr, unsigned long size) return __ioremap(physaddr, size, IOMAP_NOCACHE_SER); } -#define ioremap_uc ioremap #define ioremap_wt ioremap_wt static inline void __iomem *ioremap_wt(unsigned long physaddr, unsigned long size) diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h index 3737b48f37dd..9d93e27f7c82 100644 --- a/arch/mips/include/asm/io.h +++ b/arch/mips/include/asm/io.h @@ -167,7 +167,6 @@ void iounmap(const volatile void __iomem *addr); */ #define ioremap(offset, size) \ ioremap_prot((offset), (size), _CACHE_UNCACHED) -#define ioremap_uc ioremap /* * ioremap_cache - map bus memory into CPU space diff --git a/arch/parisc/include/asm/io.h b/arch/parisc/include/asm/io.h index 366537042465..48630c78714a 100644 --- a/arch/parisc/include/asm/io.h +++ b/arch/parisc/include/asm/io.h @@ -132,8 +132,6 @@ static inline void gsc_writeq(unsigned long long val, unsigned long addr) #define ioremap_wc(addr, size) \ ioremap_prot((addr), (size), _PAGE_IOREMAP) -#define ioremap_uc(addr, size) \ - ioremap_prot((addr), (size), _PAGE_IOREMAP) #define pci_iounmap pci_iounmap diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h index 978d687edf32..7873fc83c82c 100644 --- a/arch/powerpc/include/asm/io.h +++ b/arch/powerpc/include/asm/io.h @@ -863,7 +863,6 @@ void __iomem *ioremap_wt(phys_addr_t address, unsigned long size); #endif void __iomem *ioremap_coherent(phys_addr_t address, unsigned long size); -#define ioremap_uc(addr, size) ioremap((addr), (size)) #define ioremap_cache(addr, size) \ ioremap_prot((addr), (size), pgprot_val(PAGE_KERNEL)) diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h index b3a26b405c8d..12a892804082 100644 --- a/arch/sh/include/asm/io.h +++ b/arch/sh/include/asm/io.h @@ -278,8 +278,6 @@ unsigned long long poke_real_address_q(unsigned long long addr, ioremap_prot((addr), (size), pgprot_val(PAGE_KERNEL)) #endif /* CONFIG_MMU */ -#define ioremap_uc ioremap - /* * Convert a physical pointer to a virtual kernel pointer for /dev/mem * access diff --git a/arch/sparc/include/asm/io_64.h b/arch/sparc/include/asm/io_64.h index 9303270b22f3..d8ee1442f303 100644 --- a/arch/sparc/include/asm/io_64.h +++ b/arch/sparc/include/asm/io_64.h @@ -423,7 +423,6 @@ static inline void __iomem *ioremap(unsigned long offset, unsigned long size) return (void __iomem *)offset; } -#define ioremap_uc(X,Y) ioremap((X),(Y)) #define ioremap_wc(X,Y) ioremap((X),(Y)) #define ioremap_wt(X,Y) ioremap((X),(Y)) static inline void __iomem *ioremap_np(unsigned long offset, unsigned long size) -- 2.34.1
