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Date:   Fri, 03 Mar 2023 13:40:53 +0100
From:   "Arnd Bergmann" <arnd@arndb.de>
To:     "Baoquan He" <bhe@redhat.com>, linux-kernel@vger.kernel.org
Cc:     Linux-Arch <linux-arch@vger.kernel.org>, linux-mm@kvack.org,
        "Geert Uytterhoeven" <geert@linux-m68k.org>,
        "Luis Chamberlain" <mcgrof@kernel.org>,
        "Christoph Hellwig" <hch@infradead.org>,
        "Thomas Bogendoerfer" <tsbogend@alpha.franken.de>,
        "Helge Deller" <deller@gmx.de>,
        "Serge Semin" <fancer.lancer@gmail.com>,
        "Florian Fainelli" <f.fainelli@gmail.com>,
        "Huacai Chen" <chenhuacai@kernel.org>,
        "Jiaxun Yang" <jiaxun.yang@flygoat.com>, linux-mips@vger.kernel.org
Subject: Re: [PATCH v3 1/2] mips: add <asm-generic/io.h> including
Content-Type: text/plain
Precedence: bulk

On Fri, Mar 3, 2023, at 11:28, Baoquan He wrote:
> With the adding, some default ioremap_xx methods defined in
> asm-generic/io.h can be used. E.g the default ioremap_uc() returning
> NULL.
>
> Signed-off-by: Baoquan He <bhe@redhat.com>
> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: Helge Deller <deller@gmx.de>
> Cc: Serge Semin <fancer.lancer@gmail.com>
> Cc: Florian Fainelli <f.fainelli@gmail.com>
> Cc: Huacai Chen <chenhuacai@kernel.org>
> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
> Cc: linux-mips@vger.kernel.org

Reviewed-by: Arnd Bergmann <arnd@arndb.de>

I think this is all good. I had look at what cleanups we could do as
follow-ups:

> +#define phys_to_virt phys_to_virt
>  static inline void * phys_to_virt(unsigned long address)
>  {
>  	return __va(address);

This is the same as the asm-generic version, so the mips definition
is no longer needed.

> @@ -359,6 +360,27 @@ __BUILD_MEMORY_PFX(__raw_, q, u64, 0)
>  __BUILD_MEMORY_PFX(__mem_, q, u64, 0)
>  #endif
> 
> +#define readb readb
> +#define readw readw
> +#define readl readl
> +#define writeb writeb
> +#define writew writew
> +#define writel writel
> +
> +#ifdef CONFIG_64BIT
> +#define readq readq
> +#define writeq writeq
> +#define __raw_readq __raw_readq
> +#define __raw_writeq __raw_writeq
> +#endif
> +
> +#define __raw_readb __raw_readb
> +#define __raw_readw __raw_readw
> +#define __raw_readl __raw_readl
> +#define __raw_writeb __raw_writeb
> +#define __raw_writew __raw_writew
> +#define __raw_writel __raw_writel

The mips code defines the __raw variants with slightly different
semantics on both barriers and byteswap, which makes it impractical
to share any of the above.				

> +#define memset_io memset_io
>  static inline void memset_io(volatile void __iomem *addr, unsigned 
> char val, int count)
>  {
>  	memset((void __force *) addr, val, count);
>  }
> +#define memcpy_fromio memcpy_fromio
>  static inline void memcpy_fromio(void *dst, const volatile void 
> __iomem *src, int count)
>  {
>  	memcpy(dst, (void __force *) src, count);
>  }
> +#define memcpy_toio memcpy_toio

These are again the same as the generic version

    Arnd