On Thu, 2023-09-21 at 19:04 +0800, Baoquan He wrote:
> ioremap_uc() is only meaningful on old x86-32 systems with the PAT
> extension, and on ia64 with its slightly unconventional ioremap()
> behavior. So 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.
>
> This changes the existing behaviour, while no need to worry about
> any breakage because in the only callsite of ioremap_uc(), code
> has been adjusted to eliminate the impact. Please see
> atyfb_setup_generic() of drivers/video/fbdev/aty/atyfb_base.c.
>
> If any new invocation of ioremap_uc() need be added, please consider
> using ioremap() intead or adding a ARCH specific version if necessary.
>
> Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
> Acked-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> (powerpc)
> Acked-by: Helge Deller <deller@xxxxxx> # parisc
> Cc: linux-alpha@xxxxxxxxxxxxxxx
> Cc: linux-hexagon@xxxxxxxxxxxxxxx
> Cc: linux-m68k@xxxxxxxxxxxxxxxxxxxx
> Cc: linux-mips@xxxxxxxxxxxxxxx
> Cc: linux-parisc@xxxxxxxxxxxxxxx
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> Cc: linux-sh@xxxxxxxxxxxxxxx
> Cc: sparclinux@xxxxxxxxxxxxxxx
> ---
> Documentation/driver-api/device-io.rst | 9 +++++----
> 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, 5 insertions(+), 16 deletions(-)
>
> diff --git a/Documentation/driver-api/device-io.rst b/Documentation/driver-api/device-io.rst
> index 2c7abd234f4e..d55384b106bd 100644
> --- a/Documentation/driver-api/device-io.rst
> +++ b/Documentation/driver-api/device-io.rst
> @@ -408,11 +408,12 @@ functions for details on the CPU side of things.
> ioremap_uc()
> ------------
>
> -ioremap_uc() behaves like ioremap() except that on the x86 architecture without
> -'PAT' mode, it marks memory as uncached even when the MTRR has designated
> -it as cacheable, see Documentation/arch/x86/pat.rst.
> +ioremap_uc() is only meaningful on old x86-32 systems with the PAT extension,
> +and on ia64 with its slightly unconventional ioremap() behavior, everywhere
> +elss ioremap_uc() defaults to return NULL.
>
> -Portable drivers should avoid the use of ioremap_uc().
> +
> +Portable drivers should avoid the use of ioremap_uc(), use ioremap() instead.
>
> ioremap_cache()
> ---------------
> 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 e2b308e32a37..b7bc246dbcb1 100644
> --- a/arch/hexagon/include/asm/io.h
> +++ b/arch/hexagon/include/asm/io.h
> @@ -174,9 +174,6 @@ 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 41d8bd5adef8..1ecf255efb40 100644
> --- a/arch/mips/include/asm/io.h
> +++ b/arch/mips/include/asm/io.h
> @@ -170,7 +170,6 @@ 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 0732b743e099..21bd3e8bffce 100644
> --- a/arch/powerpc/include/asm/io.h
> +++ b/arch/powerpc/include/asm/io.h
> @@ -900,7 +900,6 @@ 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 f2f38e9d489a..790bea22c9b5 100644
> --- a/arch/sh/include/asm/io.h
> +++ b/arch/sh/include/asm/io.h
> @@ -302,8 +302,6 @@ 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)
Acked-by: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx> (SuperH)
--
.''`. John Paul Adrian Glaubitz
: :' : Debian Developer
`. `' Physicist
`- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
