blob: 0e963431b7293bb17c4b71da1eababa95569dd6c [file] [log] [blame]
/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* 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.
*
* vineetg: Feb 2009
* -For AA4 board, kernel to DMA address APIs
*/
/*
* kernel addresses are 0x800_000 based, while Bus addr are 0 based
*/
#ifndef __PLAT_DMA_ADDR_H
#define __PLAT_DMA_ADDR_H
#include <linux/device.h>
static inline unsigned long plat_dma_addr_to_kernel(struct device *dev,
dma_addr_t dma_addr)
{
return dma_addr + PAGE_OFFSET;
}
static inline dma_addr_t plat_kernel_addr_to_dma(struct device *dev, void *ptr)
{
unsigned long addr = (unsigned long)ptr;
/*
* To Catch buggy drivers which can call DMA map API with kernel vaddr
* i.e. for buffers alloc via vmalloc or ioremap which are not
* gaurnateed to be PHY contiguous and hence unfit for DMA anyways.
* On ARC kernel virtual address is 0x7000_0000 to 0x7FFF_FFFF, so
* ideally we want to check this range here, but our implementation is
* better as it checks for even worse user virtual address as well.
*/
if (likely(addr >= PAGE_OFFSET))
return addr - PAGE_OFFSET;
BUG();
return addr;
}
#endif