linux/arch/arm/include/asm/fixmap.h
Stefan Agner a5f4c561b3 ARM: 8415/1: early fixmap support for earlycon
Add early fixmap support, initially to support permanent, fixed
mapping support for early console. A temporary, early pte is
created which is migrated to a permanent mapping in paging_init.
This is also needed since the attributes may change as the memory
types are initialized. The 3MiB range of fixmap spans two pte
tables, but currently only one pte is created for early fixmap
support.

Re-add FIX_KMAP_BEGIN to the index calculation in highmem.c since
the index for kmap does not start at zero anymore. This reverts
4221e2e6b3 ("ARM: 8031/1: fixmap: remove FIX_KMAP_BEGIN and
FIX_KMAP_END") to some extent.

Cc: Mark Salter <msalter@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-08-18 14:00:29 +01:00

39 lines
1.0 KiB
C

#ifndef _ASM_FIXMAP_H
#define _ASM_FIXMAP_H
#define FIXADDR_START 0xffc00000UL
#define FIXADDR_END 0xfff00000UL
#define FIXADDR_TOP (FIXADDR_END - PAGE_SIZE)
#include <asm/kmap_types.h>
#include <asm/pgtable.h>
enum fixed_addresses {
FIX_EARLYCON_MEM_BASE,
__end_of_permanent_fixed_addresses,
FIX_KMAP_BEGIN = __end_of_permanent_fixed_addresses,
FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
/* Support writing RO kernel text via kprobes, jump labels, etc. */
FIX_TEXT_POKE0,
FIX_TEXT_POKE1,
__end_of_fixed_addresses
};
#define FIXMAP_PAGE_COMMON (L_PTE_YOUNG | L_PTE_PRESENT | L_PTE_XN | L_PTE_DIRTY)
#define FIXMAP_PAGE_NORMAL (FIXMAP_PAGE_COMMON | L_PTE_MT_WRITEBACK)
/* Used by set_fixmap_(io|nocache), both meant for mapping a device */
#define FIXMAP_PAGE_IO (FIXMAP_PAGE_COMMON | L_PTE_MT_DEV_SHARED | L_PTE_SHARED)
#define FIXMAP_PAGE_NOCACHE FIXMAP_PAGE_IO
void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
void __init early_fixmap_init(void);
#include <asm-generic/fixmap.h>
#endif