[RFC PATCH 1/2] asm-generic: io: Add exec versions of ioremap

Arnd Bergmann arnd at arndb.de
Wed Nov 26 13:32:47 PST 2014


On Wednesday 26 November 2014 15:14:00 Dave Gerlach wrote:
> @@ -66,6 +66,11 @@ extern void ioport_unmap(void __iomem *);
>  #define ioremap_wc ioremap_nocache
>  #endif
>  
> +#ifndef ARCH_HAS_IOREMAP_EXEC
> +#define ioremap_exec ioremap
> +#define ioremap_exec_nocache ioremap_nocache
> +#endif
> +
>  #ifdef CONFIG_PCI
>  /* Destroy a virtual mapping cookie for a PCI BAR (memory or IO) */
>  struct pci_dev;
> 

ioremap and ioremap_nocache are the same, and there is no
architecture-independent interface to map an MMIO range as
cached because a lot of architectures can't do that.

Also, I think there are architectures that cannot execute
from uncached memory, so I think adding this as a generic
API is not a good idea.

	Arnd



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