linux/arch/arm/include/asm/idmap.h

#ifndef __ASM_IDMAP_H
#define __ASM_IDMAP_H

#include <linux/compiler.h>
#include <asm/pgtable.h>

/* Tag a function as requiring to be executed via an identity mapping. */
#define __idmap __section(.idmap.text) noinline notrace

extern pgd_t *idmap_pgd;

void setup_mm_for_reboot(void);

#endif	/* __ASM_IDMAP_H */
ARM: idmap: populate identity map pgd at init time using .init.text When disabling and re-enabling the MMU, it is necessary to take out an identity mapping for the code that manipulates the SCTLR in order to avoid it disappearing from under our feet. This is useful when soft rebooting and returning from CPU suspend. This patch allocates a set of page tables during boot and populates them with an identity mapping for the .idmap.text section. This means that users of the identity map do not need to manage their own pgd and can instead annotate their functions with __idmap or, in the case of assembly code, place them in the correct section. Acked-by: Dave Martin <dave.martin@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> 2011-09-30 10:43:29 +00:00			`#ifndef __ASM_IDMAP_H`
			`#define __ASM_IDMAP_H`

			`#include <linux/compiler.h>`
			`#include <asm/pgtable.h>`

			`/* Tag a function as requiring to be executed via an identity mapping. */`
			`#define __idmap __section(.idmap.text) noinline notrace`

			`extern pgd_t *idmap_pgd;`

			`void setup_mm_for_reboot(void);`

			`#endif /* __ASM_IDMAP_H */`