omap iommu: simple virtual address space management

This patch provides a device drivers, which has a omap iommu, with
address mapping APIs between device virtual address(iommu), physical
address and MPU virtual address.

There are 4 possible patterns for iommu virtual address(iova/da) mapping.

    |iova/			  mapping		iommu_		page
    | da	pa	va	(d)-(p)-(v)		function	type
  ---------------------------------------------------------------------------
  1 | c		c	c	 1 - 1 - 1	  _kmap() / _kunmap()	s
  2 | c		c,a	c	 1 - 1 - 1	_kmalloc()/ _kfree()	s
  3 | c		d	c	 1 - n - 1	  _vmap() / _vunmap()	s
  4 | c		d,a	c	 1 - n - 1	_vmalloc()/ _vfree()	n*

    'iova':	device iommu virtual address
    'da':	alias of 'iova'
    'pa':	physical address
    'va':	mpu virtual address

    'c':	contiguous memory area
    'd':	dicontiguous memory area
    'a':	anonymous memory allocation
    '()':	optional feature

    'n':	a normal page(4KB) size is used.
    's':	multiple iommu superpage(16MB, 1MB, 64KB, 4KB) size is used.

    '*':	not yet, but feasible.

Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/arch/arm/include/asm/mach/map.h b/arch/arm/include/asm/mach/map.h
index 58cf91f..742c2aa 100644
--- a/arch/arm/include/asm/mach/map.h
+++ b/arch/arm/include/asm/mach/map.h
@@ -30,6 +30,14 @@ struct map_desc {
 
 #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