linux/arch/arm/include/asm/mach/map.h
Marek Szyprowski c790950928 ARM: integrate CMA with DMA-mapping subsystem
This patch adds support for CMA to dma-mapping subsystem for ARM
architecture. By default a global CMA area is used, but specific devices
are allowed to have their private memory areas if required (they can be
created with dma_declare_contiguous() function during board
initialisation).

Contiguous memory areas reserved for DMA are remapped with 2-level page
tables on boot. Once a buffer is requested, a low memory kernel mapping
is updated to to match requested memory access type.

GFP_ATOMIC allocations are performed from special pool which is created
early during boot. This way remapping page attributes is not needed on
allocation time.

CMA has been enabled unconditionally for ARMv6+ systems.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
CC: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Rob Clark <rob.clark@linaro.org>
Tested-by: Ohad Ben-Cohen <ohad@wizery.com>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Tested-by: Robert Nelson <robertcnelson@gmail.com>
Tested-by: Barry Song <Baohua.Song@csr.com>
2012-05-21 15:09:38 +02:00

47 lines
1.2 KiB
C

/*
* arch/arm/include/asm/map.h
*
* Copyright (C) 1999-2000 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Page table mapping constructs and function prototypes
*/
#include <asm/io.h>
struct map_desc {
unsigned long virtual;
unsigned long pfn;
unsigned long length;
unsigned int type;
};
/* types 0-3 are defined in asm/io.h */
#define MT_UNCACHED 4
#define MT_CACHECLEAN 5
#define MT_MINICLEAN 6
#define MT_LOW_VECTORS 7
#define MT_HIGH_VECTORS 8
#define MT_MEMORY 9
#define MT_ROM 10
#define MT_MEMORY_NONCACHED 11
#define MT_MEMORY_DTCM 12
#define MT_MEMORY_ITCM 13
#define MT_MEMORY_SO 14
#define MT_MEMORY_DMA_READY 15
#ifdef CONFIG_MMU
extern void iotable_init(struct map_desc *, int);
struct mem_type;
extern const struct mem_type *get_mem_type(unsigned int type);
/*
* external interface to remap single page with appropriate type
*/
extern int ioremap_page(unsigned long virt, unsigned long phys,
const struct mem_type *mtype);
#else
#define iotable_init(map,num) do { } while (0)
#endif