Re: [PATCH -next] powerpc/mpic_msgr: fix cast removes address space of expression warnings

[Christophe Leroy <christophe.leroy@csgroup.eu>]

Le 01/09/2022 à 10:54, ruanjinjie a écrit :
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> 
> When build Linux kernel, encounter the following warnings:
> 
> ./arch/powerpc/sysdev/mpic_msgr.c:230:38: warning: cast removes address space '__iomem' of expression
> ./arch/powerpc/sysdev/mpic_msgr.c:230:27: warning: incorrect type in assignment (different address spaces)
> 
> The data type of msgr->mer and msgr->base are 'u32 __iomem *', but
> converted to 'u32 *' and 'u8 *' directly and cause above warnings, now
> recover their data types to fix these warnings.

I think the best would be to change MPIC_MSGR_MER_OFFSET to 0x40 and 
then drop the casts completely:

	msgr->mer = msgr->base + MPIC_MSGR_MER_OFFSET;

> 
> Signed-off-by: ruanjinjie <ruanjinjie@huawei.com>
> ---
>   arch/powerpc/sysdev/mpic_msgr.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/sysdev/mpic_msgr.c b/arch/powerpc/sysdev/mpic_msgr.c
> index 698fefaaa6dd..cbb0d24f15ba 100644
> --- a/arch/powerpc/sysdev/mpic_msgr.c
> +++ b/arch/powerpc/sysdev/mpic_msgr.c
> @@ -227,7 +227,7 @@ static int mpic_msgr_probe(struct platform_device *dev)
> 
>                  reg_number = block_number * MPIC_MSGR_REGISTERS_PER_BLOCK + i;
>                  msgr->base = msgr_block_addr + i * MPIC_MSGR_STRIDE;
> -               msgr->mer = (u32 *)((u8 *)msgr->base + MPIC_MSGR_MER_OFFSET);
> +               msgr->mer = (u32 __iomem *)((u8 __iomem *)msgr->base + MPIC_MSGR_MER_OFFSET);
>                  msgr->in_use = MSGR_FREE;
>                  msgr->num = i;
>                  raw_spin_lock_init(&msgr->lock);
> --
> 2.25.1
>