summaryrefslogtreecommitdiff
path: root/arch/avr32/include/asm/dma-mapping.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/avr32/include/asm/dma-mapping.h')
-rw-r--r--arch/avr32/include/asm/dma-mapping.h349
1 files changed, 349 insertions, 0 deletions
diff --git a/arch/avr32/include/asm/dma-mapping.h b/arch/avr32/include/asm/dma-mapping.h
new file mode 100644
index 000000000000..0399359ab5d8
--- /dev/null
+++ b/arch/avr32/include/asm/dma-mapping.h
@@ -0,0 +1,349 @@
+#ifndef __ASM_AVR32_DMA_MAPPING_H
+#define __ASM_AVR32_DMA_MAPPING_H
+
+#include <linux/mm.h>
+#include <linux/device.h>
+#include <linux/scatterlist.h>
+#include <asm/processor.h>
+#include <asm/cacheflush.h>
+#include <asm/io.h>
+
+extern void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
+ int direction);
+
+/*
+ * Return whether the given device DMA address mask can be supported
+ * properly. For example, if your device can only drive the low 24-bits
+ * during bus mastering, then you would pass 0x00ffffff as the mask
+ * to this function.
+ */
+static inline int dma_supported(struct device *dev, u64 mask)
+{
+ /* Fix when needed. I really don't know of any limitations */
+ return 1;
+}
+
+static inline int dma_set_mask(struct device *dev, u64 dma_mask)
+{
+ if (!dev->dma_mask || !dma_supported(dev, dma_mask))
+ return -EIO;
+
+ *dev->dma_mask = dma_mask;
+ return 0;
+}
+
+/*
+ * dma_map_single can't fail as it is implemented now.
+ */
+static inline int dma_mapping_error(struct device *dev, dma_addr_t addr)
+{
+ return 0;
+}
+
+/**
+ * dma_alloc_coherent - allocate consistent memory for DMA
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @size: required memory size
+ * @handle: bus-specific DMA address
+ *
+ * Allocate some uncached, unbuffered memory for a device for
+ * performing DMA. This function allocates pages, and will
+ * return the CPU-viewed address, and sets @handle to be the
+ * device-viewed address.
+ */
+extern void *dma_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t *handle, gfp_t gfp);
+
+/**
+ * dma_free_coherent - free memory allocated by dma_alloc_coherent
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @size: size of memory originally requested in dma_alloc_coherent
+ * @cpu_addr: CPU-view address returned from dma_alloc_coherent
+ * @handle: device-view address returned from dma_alloc_coherent
+ *
+ * Free (and unmap) a DMA buffer previously allocated by
+ * dma_alloc_coherent().
+ *
+ * References to memory and mappings associated with cpu_addr/handle
+ * during and after this call executing are illegal.
+ */
+extern void dma_free_coherent(struct device *dev, size_t size,
+ void *cpu_addr, dma_addr_t handle);
+
+/**
+ * dma_alloc_writecombine - allocate write-combining memory for DMA
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @size: required memory size
+ * @handle: bus-specific DMA address
+ *
+ * Allocate some uncached, buffered memory for a device for
+ * performing DMA. This function allocates pages, and will
+ * return the CPU-viewed address, and sets @handle to be the
+ * device-viewed address.
+ */
+extern void *dma_alloc_writecombine(struct device *dev, size_t size,
+ dma_addr_t *handle, gfp_t gfp);
+
+/**
+ * dma_free_coherent - free memory allocated by dma_alloc_writecombine
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @size: size of memory originally requested in dma_alloc_writecombine
+ * @cpu_addr: CPU-view address returned from dma_alloc_writecombine
+ * @handle: device-view address returned from dma_alloc_writecombine
+ *
+ * Free (and unmap) a DMA buffer previously allocated by
+ * dma_alloc_writecombine().
+ *
+ * References to memory and mappings associated with cpu_addr/handle
+ * during and after this call executing are illegal.
+ */
+extern void dma_free_writecombine(struct device *dev, size_t size,
+ void *cpu_addr, dma_addr_t handle);
+
+/**
+ * dma_map_single - map a single buffer for streaming DMA
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @cpu_addr: CPU direct mapped address of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * Ensure that any data held in the cache is appropriately discarded
+ * or written back.
+ *
+ * The device owns this memory once this call has completed. The CPU
+ * can regain ownership by calling dma_unmap_single() or dma_sync_single().
+ */
+static inline dma_addr_t
+dma_map_single(struct device *dev, void *cpu_addr, size_t size,
+ enum dma_data_direction direction)
+{
+ dma_cache_sync(dev, cpu_addr, size, direction);
+ return virt_to_bus(cpu_addr);
+}
+
+/**
+ * dma_unmap_single - unmap a single buffer previously mapped
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @handle: DMA address of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * Unmap a single streaming mode DMA translation. The handle and size
+ * must match what was provided in the previous dma_map_single() call.
+ * All other usages are undefined.
+ *
+ * After this call, reads by the CPU to the buffer are guaranteed 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)
+{
+
+}
+
+/**
+ * dma_map_page - map a portion of a page for streaming DMA
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @page: page that buffer resides in
+ * @offset: offset into page for start of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * Ensure that any data held in the cache is appropriately discarded
+ * or written back.
+ *
+ * The device owns this memory once this call has completed. The CPU
+ * can regain ownership by calling dma_unmap_page() or dma_sync_single().
+ */
+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)
+{
+ return dma_map_single(dev, page_address(page) + offset,
+ size, direction);
+}
+
+/**
+ * dma_unmap_page - unmap a buffer previously mapped through dma_map_page()
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @handle: DMA address of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * Unmap a single streaming mode DMA translation. The handle and size
+ * must match what was provided in the previous dma_map_single() call.
+ * All other usages are undefined.
+ *
+ * After this call, reads by the CPU to the buffer are guaranteed to see
+ * whatever the device wrote there.
+ */
+static inline void
+dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size,
+ enum dma_data_direction direction)
+{
+ dma_unmap_single(dev, dma_address, size, direction);
+}
+
+/**
+ * dma_map_sg - map a set of SG buffers for streaming mode DMA
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @sg: list of buffers
+ * @nents: number of buffers to map
+ * @dir: DMA transfer direction
+ *
+ * Map a set of buffers described by scatterlist in streaming
+ * mode for DMA. This is the scatter-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 *sg, int nents,
+ enum dma_data_direction direction)
+{
+ int i;
+
+ for (i = 0; i < nents; i++) {
+ char *virt;
+
+ sg[i].dma_address = page_to_bus(sg_page(&sg[i])) + sg[i].offset;
+ virt = sg_virt(&sg[i]);
+ dma_cache_sync(dev, virt, sg[i].length, direction);
+ }
+
+ return nents;
+}
+
+/**
+ * dma_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @sg: list of buffers
+ * @nents: number of buffers to map
+ * @dir: DMA transfer direction
+ *
+ * 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)
+{
+
+}
+
+/**
+ * dma_sync_single_for_cpu
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @handle: DMA address of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * Make physical memory consistent for a single streaming mode DMA
+ * translation after a transfer.
+ *
+ * If you perform a dma_map_single() but wish to interrogate the
+ * buffer using the cpu, yet do not wish to teardown the DMA mapping,
+ * you must call this function before doing so. At the next point you
+ * give the DMA address back to the card, you must first perform a
+ * dma_sync_single_for_device, and then 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)
+{
+ /*
+ * No need to do anything since the CPU isn't supposed to
+ * touch this memory after we flushed it at mapping- or
+ * sync-for-device time.
+ */
+}
+
+static inline void
+dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle,
+ size_t size, enum dma_data_direction direction)
+{
+ dma_cache_sync(dev, bus_to_virt(dma_handle), size, direction);
+}
+
+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)
+{
+ /* just sync everything, that's all the pci API can do */
+ dma_sync_single_for_cpu(dev, dma_handle, offset+size, 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)
+{
+ /* just sync everything, that's all the pci API can do */
+ dma_sync_single_for_device(dev, dma_handle, offset+size, direction);
+}
+
+/**
+ * dma_sync_sg_for_cpu
+ * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
+ * @sg: list of buffers
+ * @nents: number of buffers to map
+ * @dir: DMA transfer direction
+ *
+ * Make physical memory consistent for a set of streaming
+ * mode DMA translations after a transfer.
+ *
+ * The same as dma_sync_single_for_* 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 nents, enum dma_data_direction direction)
+{
+ /*
+ * No need to do anything since the CPU isn't supposed to
+ * touch this memory after we flushed it at mapping- or
+ * sync-for-device time.
+ */
+}
+
+static inline void
+dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction direction)
+{
+ int i;
+
+ for (i = 0; i < nents; i++) {
+ dma_cache_sync(dev, sg_virt(&sg[i]), sg[i].length, direction);
+ }
+}
+
+/* Now for the API extensions over the pci_ one */
+
+#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)
+
+static inline int dma_is_consistent(struct device *dev, dma_addr_t dma_addr)
+{
+ return 1;
+}
+
+static inline int dma_get_cache_alignment(void)
+{
+ return boot_cpu_data.dcache.linesz;
+}
+
+#endif /* __ASM_AVR32_DMA_MAPPING_H */