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author | Mark Salter <msalter@redhat.com> | 2014-04-07 15:39:48 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-07 16:36:15 -0700 |
commit | 9e5c33d7aeeef62e5fa7e74f94432685bd03026b (patch) | |
tree | ff62a742103d422f2c74c192af434a0023324c0e /include/asm-generic | |
parent | 6b550f6f2004017f1b4633d2c9e39b610bfe84f0 (diff) | |
download | linux-stable-9e5c33d7aeeef62e5fa7e74f94432685bd03026b.tar.gz linux-stable-9e5c33d7aeeef62e5fa7e74f94432685bd03026b.tar.bz2 linux-stable-9e5c33d7aeeef62e5fa7e74f94432685bd03026b.zip |
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>
Diffstat (limited to 'include/asm-generic')
-rw-r--r-- | include/asm-generic/early_ioremap.h | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/include/asm-generic/early_ioremap.h b/include/asm-generic/early_ioremap.h new file mode 100644 index 000000000000..a5de55c04fb2 --- /dev/null +++ b/include/asm-generic/early_ioremap.h @@ -0,0 +1,42 @@ +#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_ */ |