* Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corporation
*
* Provide default implementations of the DMA mapping callbacks for
- * directly mapped busses and busses using the iommu infrastructure
+ * directly mapped busses.
*/
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <asm/bug.h>
-#include <asm/iommu.h>
#include <asm/abs_addr.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->archdata.numa_node);
-}
-
-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);
-
/*
* Generic direct DMA implementation
*
* This implementation supports a per-device offset that can be applied if
* the address at which memory is visible to devices is not 0. Platform code
* can set archdata.dma_data to an unsigned long holding the offset. By
- * default the offset is zero.
+ * default the offset is PCI_DRAM_OFFSET.
*/
static unsigned long get_dma_direct_offset(struct device *dev)
{
- return (unsigned long)dev->archdata.dma_data;
+ if (dev)
+ return (unsigned long)dev->archdata.dma_data;
+
+ return PCI_DRAM_OFFSET;
}
-static void *dma_direct_alloc_coherent(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t flag)
+void *dma_direct_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flag)
{
- struct page *page;
void *ret;
- int node = dev->archdata.numa_node;
+#ifdef CONFIG_NOT_COHERENT_CACHE
+ ret = __dma_alloc_coherent(size, dma_handle, flag);
+ if (ret == NULL)
+ return NULL;
+ *dma_handle += get_dma_direct_offset(dev);
+ return ret;
+#else
+ struct page *page;
+ int node = dev_to_node(dev);
+
+ /* ignore region specifiers */
+ flag &= ~(__GFP_HIGHMEM);
page = alloc_pages_node(node, flag, get_order(size));
if (page == NULL)
*dma_handle = virt_to_abs(ret) + get_dma_direct_offset(dev);
return ret;
+#endif
}
-static void dma_direct_free_coherent(struct device *dev, size_t size,
- void *vaddr, dma_addr_t dma_handle)
+void dma_direct_free_coherent(struct device *dev, size_t size,
+ void *vaddr, dma_addr_t dma_handle)
{
+#ifdef CONFIG_NOT_COHERENT_CACHE
+ __dma_free_coherent(size, vaddr);
+#else
free_pages((unsigned long)vaddr, get_order(size));
-}
-
-static dma_addr_t dma_direct_map_single(struct device *dev, void *ptr,
- size_t size,
- enum dma_data_direction direction,
- struct dma_attrs *attrs)
-{
- return virt_to_abs(ptr) + get_dma_direct_offset(dev);
-}
-
-static void dma_direct_unmap_single(struct device *dev, dma_addr_t dma_addr,
- size_t size,
- enum dma_data_direction direction,
- struct dma_attrs *attrs)
-{
+#endif
}
static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
for_each_sg(sgl, sg, nents, i) {
sg->dma_address = sg_phys(sg) + get_dma_direct_offset(dev);
sg->dma_length = sg->length;
+ __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
}
return nents;
static int dma_direct_dma_supported(struct device *dev, u64 mask)
{
+#ifdef CONFIG_PPC64
/* Could be improved to check for memory though it better be
* done via some global so platforms can set the limit in case
* they have limited DMA windows
*/
return mask >= DMA_32BIT_MASK;
+#else
+ return 1;
+#endif
+}
+
+static inline dma_addr_t dma_direct_map_page(struct device *dev,
+ struct page *page,
+ unsigned long offset,
+ size_t size,
+ enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ BUG_ON(dir == DMA_NONE);
+ __dma_sync_page(page, offset, size, dir);
+ return page_to_phys(page) + offset + get_dma_direct_offset(dev);
+}
+
+static inline void dma_direct_unmap_page(struct device *dev,
+ dma_addr_t dma_address,
+ size_t size,
+ enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
}
struct dma_mapping_ops dma_direct_ops = {
.alloc_coherent = dma_direct_alloc_coherent,
.free_coherent = dma_direct_free_coherent,
- .map_single = dma_direct_map_single,
- .unmap_single = dma_direct_unmap_single,
.map_sg = dma_direct_map_sg,
.unmap_sg = dma_direct_unmap_sg,
.dma_supported = dma_direct_dma_supported,
+ .map_page = dma_direct_map_page,
+ .unmap_page = dma_direct_unmap_page,
};
EXPORT_SYMBOL(dma_direct_ops);