/* DMA mapping routines for the MN10300 arch
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#ifndef _ASM_DMA_MAPPING_H
#define _ASM_DMA_MAPPING_H
#include <linux/mm.h>
#include <linux/scatterlist.h>
#include <asm/cache.h>
#include <asm/io.h>
extern void *dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, int flag);
extern void dma_free_coherent(struct device *dev, size_t size,
void *vaddr, dma_addr_t dma_handle);
#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent((d), (s), (h), (f))
#define dma_free_noncoherent(d, s, v, h) dma_free_coherent((d), (s), (v), (h))
/*
* Map a single buffer of the indicated size for DMA in streaming mode. The
* 32-bit bus address to use is returned.
*
* Once the device is given the dma address, the device owns this memory until
* either pci_unmap_single or pci_dma_sync_single is performed.
*/
static inline
dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
enum dma_data_direction direction)
{
BUG_ON(direction == DMA_NONE);
mn10300_dcache_flush_inv();
return virt_to_bus(ptr);
}
/*
* Unmap a single streaming mode DMA translation. The dma_addr and size must
* match what was provided for in a previous pci_map_single call. All other
* usages are undefined.
*
* After this call, reads by the cpu to the buffer are guarenteed to see
* whatever the device wrote there.
*/
static inline
void dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction direction)
{
BUG_ON(direction == DMA_NONE);
}
/*
* Map a set of buffers described by scatterlist in streaming mode for DMA.
* This is the scather-gather version of the above pci_map_single interface.
* Here the scatter gather list elements are each tagged with the appropriate
* dma address and length. They are obtained via sg_dma_{address,length}(SG).
*
* NOTE: An implementation may be able to use a smaller number of DMA
* address/length pairs than there are SG table elements. (for example
* via virtual mapping capabilities) The routine returns the number of
* addr/length pairs actually used, at most nents.
*
* Device ownership issues as mentioned above for pci_map_single are the same
* here.
*/
static inline
int dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
enum dma_data_direction direction)
{
struct scatterlist *sg;
int i;
BUG_ON(!valid_dma_direction(direction));
WARN_ON(nents == 0 || sglist[0].length == 0);
for_each_sg(sglist, sg, nents, i) {
BUG_ON(!sg_page(sg));
sg->dma_address = sg_phys(sg);
}
mn10300_dcache_flush_inv();
return nents;
}
/*
* Unmap a set of streaming mode DMA translations.
* Again, cpu read rules concerning calls here are the same as for
* pci_unmap_single() above.
*/
static inline
void dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries,
enum dma_data_direction direction)
{
BUG_ON(!valid_dma_direction(direction));
}
/*
* pci_{map,unmap}_single_page maps a kernel page to a dma_addr_t. identical
* to pci_map_single, but takes a struct page instead of a virtual address
*/
static inline
dma_addr_t dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction direction)
{
BUG_ON(direction == DMA_NONE);
return page_to_bus(page) + offset;
}
static inline
void dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size,
enum dma_data_direction direction)
{
BUG_ON(direction == DMA_NONE);
}
/*
* Make physical memory consistent for a single streaming mode DMA translation
* after a transfer.
*
* If you perform a pci_map_single() but wish to interrogate the buffer using
* the cpu, yet do not wish to teardown the PCI dma mapping, you must call this
* function before doing so. At the next point you give the PCI dma address
* back to the card, the device again owns the buffer.
*/
static inline
void dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
size_t size, enum dma_data_direction direction)
{
}
static inline
void dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle,
size_t size, enum dma_data_direction direction)
{
mn10300_dcache_flush_inv();
}
static inline
void dma_sync_single_range_for_cpu(struct device *dev, dma_addr_t dma_handle,
unsigned long offset, size_t size,
enum dma_data_direction direction)
{
}
static inline void
dma_sync_single_range_for_device(struct device *dev, dma_addr_t dma_handle,
unsigned long offset, size_t size,
enum dma_data_direction direction)
{
mn10300_dcache_flush_inv();
}
/*
* Make physical memory consistent for a set of streaming mode DMA translations
* after a transfer.
*
* The same as pci_dma_sync_single but for a scatter-gather list, same rules
* and usage.
*/
static inline
void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
int nelems, enum dma_data_direction direction)
{
}
static inline
void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
int nelems, enum dma_data_direction direction)
{
mn10300_dcache_flush_inv();
}
static inline
int dma_mapping_error(dma_addr_t dma_addr)
{
return 0;
}
/*
* Return whether the given PCI device DMA address mask can be supported
* properly. For example, if your device can only drive the low 24-bits during
* PCI bus mastering, then you would pass 0x00ffffff as the mask to this
* function.
*/
static inline
int dma_supported(struct device *dev, u64 mask)
{
/*
* we fall back to GFP_DMA when the mask isn't all 1s, so we can't
* guarantee allocations that must be within a tighter range than
* GFP_DMA
*/
if (mask < 0x00ffffff)
return 0;
return 1;
}
static inline
int dma_set_mask(struct device *dev, u64 mask)
{
if (!dev->dma_mask || !dma_supported(dev, mask))
return -EIO;
*dev->dma_mask = mask;
return 0;
}
static inline
int dma_get_cache_alignment(void)
{
return 1 << L1_CACHE_SHIFT;
}
#define dma_is_consistent(d) (1)
static inline
void dma_cache_sync(void *vaddr, size_t size,
enum dma_data_direction direction)
{
mn10300_dcache_flush_inv();
}
#endif
