104 строки
3.1 KiB
C
104 строки
3.1 KiB
C
/*
|
|
* Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corporation
|
|
*
|
|
* Provide default implementations of the DMA mapping callbacks for
|
|
* busses using the iommu infrastructure
|
|
*/
|
|
|
|
#include <asm/iommu.h>
|
|
|
|
/*
|
|
* Generic iommu implementation
|
|
*/
|
|
|
|
/* Allocates a contiguous real buffer and creates mappings over it.
|
|
* Returns the virtual address of the buffer and sets dma_handle
|
|
* to the dma address (mapping) of the first page.
|
|
*/
|
|
static void *dma_iommu_alloc_coherent(struct device *dev, size_t size,
|
|
dma_addr_t *dma_handle, gfp_t flag)
|
|
{
|
|
return iommu_alloc_coherent(dev, dev->archdata.dma_data, size,
|
|
dma_handle, device_to_mask(dev), flag,
|
|
dev_to_node(dev));
|
|
}
|
|
|
|
static void dma_iommu_free_coherent(struct device *dev, size_t size,
|
|
void *vaddr, dma_addr_t dma_handle)
|
|
{
|
|
iommu_free_coherent(dev->archdata.dma_data, size, vaddr, dma_handle);
|
|
}
|
|
|
|
/* Creates TCEs for a user provided buffer. The user buffer must be
|
|
* contiguous real kernel storage (not vmalloc). The address of the buffer
|
|
* passed here is the kernel (virtual) address of the buffer. The buffer
|
|
* need not be page aligned, the dma_addr_t returned will point to the same
|
|
* byte within the page as vaddr.
|
|
*/
|
|
static dma_addr_t dma_iommu_map_single(struct device *dev, void *vaddr,
|
|
size_t size,
|
|
enum dma_data_direction direction,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
return iommu_map_single(dev, dev->archdata.dma_data, vaddr, size,
|
|
device_to_mask(dev), direction, attrs);
|
|
}
|
|
|
|
|
|
static void dma_iommu_unmap_single(struct device *dev, dma_addr_t dma_handle,
|
|
size_t size,
|
|
enum dma_data_direction direction,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
iommu_unmap_single(dev->archdata.dma_data, dma_handle, size, direction,
|
|
attrs);
|
|
}
|
|
|
|
|
|
static int dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist,
|
|
int nelems, enum dma_data_direction direction,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
return iommu_map_sg(dev, dev->archdata.dma_data, sglist, nelems,
|
|
device_to_mask(dev), direction, attrs);
|
|
}
|
|
|
|
static void dma_iommu_unmap_sg(struct device *dev, struct scatterlist *sglist,
|
|
int nelems, enum dma_data_direction direction,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
iommu_unmap_sg(dev->archdata.dma_data, sglist, nelems, direction,
|
|
attrs);
|
|
}
|
|
|
|
/* We support DMA to/from any memory page via the iommu */
|
|
static int dma_iommu_dma_supported(struct device *dev, u64 mask)
|
|
{
|
|
struct iommu_table *tbl = dev->archdata.dma_data;
|
|
|
|
if (!tbl || tbl->it_offset > mask) {
|
|
printk(KERN_INFO
|
|
"Warning: IOMMU offset too big for device mask\n");
|
|
if (tbl)
|
|
printk(KERN_INFO
|
|
"mask: 0x%08lx, table offset: 0x%08lx\n",
|
|
mask, tbl->it_offset);
|
|
else
|
|
printk(KERN_INFO "mask: 0x%08lx, table unavailable\n",
|
|
mask);
|
|
return 0;
|
|
} else
|
|
return 1;
|
|
}
|
|
|
|
struct dma_mapping_ops dma_iommu_ops = {
|
|
.alloc_coherent = dma_iommu_alloc_coherent,
|
|
.free_coherent = dma_iommu_free_coherent,
|
|
.map_single = dma_iommu_map_single,
|
|
.unmap_single = dma_iommu_unmap_single,
|
|
.map_sg = dma_iommu_map_sg,
|
|
.unmap_sg = dma_iommu_unmap_sg,
|
|
.dma_supported = dma_iommu_dma_supported,
|
|
};
|
|
EXPORT_SYMBOL(dma_iommu_ops);
|