Subject: Re: [PATCH] media: fsl-viu: Use proper check for presence of {out, in}_be32()

From: Michael Ellerman <[email-masked]>
Date: Fri, 20 Nov 2020 17:25:29 +1100

Fabio Estevam <[email-masked]> writes:
> From: Geert Uytterhoeven <[email-masked]>
>
> When compile-testing on m68k or microblaze:
>
>     drivers/media/platform/fsl-viu.c:41:1: warning: "out_be32" redefined
>     drivers/media/platform/fsl-viu.c:42:1: warning: "in_be32" redefined
>
> Fix this by replacing the check for PowerPC by checks for the presence
> of {out,in}_be32().
>
> As PowerPC implements the be32 accessors using inline functions instead
> of macros, identity definions are added for all accessors to make the
> above checks work.
>
> Fixes: 29d750686331a1a9 ("media: fsl-viu: allow building it with COMPILE_TEST")
> Signed-off-by: Geert Uytterhoeven <[email-masked]>
> [fabio: adapt to mainline]
> Signed-off-by: Fabio Estevam <[email-masked]>
> ---
>  arch/powerpc/include/asm/io.h    | 14 ++++++++++++++
>  drivers/media/platform/fsl-viu.c |  5 +++--
>  2 files changed, 17 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h
> index 58635960403c..fcb250db110d 100644
> --- a/arch/powerpc/include/asm/io.h
> +++ b/arch/powerpc/include/asm/io.h
> @@ -194,6 +194,20 @@ static inline void out_be64(volatile u64 __iomem *addr, u64 val)
>  #endif
>  #endif /* __powerpc64__ */
>  
> +#define in_be16 in_be16
> +#define in_be32 in_be32
> +#define in_be64 in_be64
> +#define in_le16 in_le16
> +#define in_le32 in_le32
> +#define in_le64 in_le64
> +
> +#define out_be16 out_be16
> +#define out_be32 out_be32
> +#define out_be64 out_be64
> +#define out_le16 out_le16
> +#define out_le32 out_le32
> +#define out_le64 out_le64

I'd rather not have to carry this in arch code just for one driver.

> diff --git a/drivers/media/platform/fsl-viu.c b/drivers/media/platform/fsl-viu.c
> index 4f2a0f992905..bb6c291ed6dc 100644
> --- a/drivers/media/platform/fsl-viu.c
> +++ b/drivers/media/platform/fsl-viu.c
> @@ -31,9 +31,10 @@
>  #define DRV_NAME		"fsl_viu"
>  #define VIU_VERSION		"0.5.1"
>  
> -/* Allow building this driver with COMPILE_TEST */
> -#if !defined(CONFIG_PPC) && !defined(CONFIG_MICROBLAZE) && !defined(CONFIG_M68K)
> +#ifndef out_be32
>  #define out_be32(v, a)	iowrite32be(a, (void __iomem *)v)
> +#endif
> +#ifndef in_be32
>  #define in_be32(a)	ioread32be((void __iomem *)a)
>  #endif

Can't the driver just use ioread/write32be() on all platforms?

cheers