linux/include/asm-generic/early_ioremap.h
Mark Salter 9e5c33d7ae mm: create generic early_ioremap() support
This patch creates a generic implementation of early_ioremap() support
based on the existing x86 implementation.  early_ioremp() is useful for
early boot code which needs to temporarily map I/O or memory regions
before normal mapping functions such as ioremap() are available.

Some architectures have optional MMU.  In the no-MMU case, the remap
functions simply return the passed in physical address and the unmap
functions do nothing.

Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:36:15 -07:00

42 lines
1.3 KiB
C

#ifndef _ASM_EARLY_IOREMAP_H_
#define _ASM_EARLY_IOREMAP_H_
#include <linux/types.h>
/*
* early_ioremap() and early_iounmap() are for temporary early boot-time
* mappings, before the real ioremap() is functional.
*/
extern void __iomem *early_ioremap(resource_size_t phys_addr,
unsigned long size);
extern void *early_memremap(resource_size_t phys_addr,
unsigned long size);
extern void early_iounmap(void __iomem *addr, unsigned long size);
extern void early_memunmap(void *addr, unsigned long size);
/*
* Weak function called by early_ioremap_reset(). It does nothing, but
* architectures may provide their own version to do any needed cleanups.
*/
extern void early_ioremap_shutdown(void);
#if defined(CONFIG_GENERIC_EARLY_IOREMAP) && defined(CONFIG_MMU)
/* Arch-specific initialization */
extern void early_ioremap_init(void);
/* Generic initialization called by architecture code */
extern void early_ioremap_setup(void);
/*
* Called as last step in paging_init() so library can act
* accordingly for subsequent map/unmap requests.
*/
extern void early_ioremap_reset(void);
#else
static inline void early_ioremap_init(void) { }
static inline void early_ioremap_setup(void) { }
static inline void early_ioremap_reset(void) { }
#endif
#endif /* _ASM_EARLY_IOREMAP_H_ */