From 69d3a84a646d6ad6cd693a7a3d5b9af414113d2c Mon Sep 17 00:00:00 2001 From: Hiroshi DOYU Date: Wed, 28 Jan 2009 21:32:08 +0200 Subject: 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 --- arch/arm/mm/mmu.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arm/mm/mmu.c') diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index e6344ece00c..70974d75a07 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -255,6 +255,7 @@ const struct mem_type *get_mem_type(unsigned int type) { return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL; } +EXPORT_SYMBOL(get_mem_type); /* * Adjust the PMD section entries according to the CPU in use. -- cgit v1.2.3