On Thu, 19 May 2022 16:25:50 +0800 Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:
> Add special hook for architecture to verify or setup addr, size
> or prot when ioremap() or iounmap(), which will make the generic
> ioremap more useful.
>
> arch_ioremap() return a pointer,
> - IS_ERR means return an error
> - NULL means continue to remap
> - a non-NULL, non-IS_ERR pointer is directly returned
> arch_iounmap() return a int value,
> - 0 means continue to vunmap
> - error code means skip vunmap and return directly
>
> ...
>
> --- a/include/asm-generic/io.h
> +++ b/include/asm-generic/io.h
> @@ -964,6 +964,30 @@ static inline void iounmap(volatile void __iomem *addr)
> #elif defined(CONFIG_GENERIC_IOREMAP)
> #include <linux/pgtable.h>
>
> +/*
> + * Arch code can implement the following two special hooks when using GENERIC_IOREMAP
> + * arch_ioremap() return a pointer,
> + * - IS_ERR means return an error
> + * - NULL means continue to remap
> + * - a non-NULL, non-IS_ERR pointer is returned directly
> + * arch_iounmap() return a int,
> + * - 0 means continue to vunmap
> + * - error code means skip vunmap and return directly
> + */
> +#ifndef arch_ioremap
> +static inline void __iomem *arch_ioremap(phys_addr_t phys_addr, size_t size, unsigned long prot)
> +{
> + return NULL;
> +}
Maybe should do
#define arch_ioremap arch_ioremap
here
> +#endif
> +
> +#ifndef arch_iounmap
> +static inline int arch_iounmap(void __iomem *addr)
> +{
> + return 0;
> +}
and here.
It shouldn't matter a lot because this file has inclusion guards.
However it seems tidier and perhaps other code will want to know
whether this was defined. Dunno.
Otherwise,
Acked-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Please take this patch and [2/6] and [3/6] via the appropriate arm tree.
