nios2: DMA mapping API

This patch adds support for the DMA mapping API.

Signed-off-by: Ley Foon Tan <lftan@altera.com>

1 files changed, 140 insertions, 0 deletions

diff --git a/arch/nios2/include/asm/dma-mapping.h b/arch/nios2/include/asm/dma-mapping.h
new file mode 100644
index 000000000000..b5567233f7f1
--- /dev/null
+++ b/arch/nios2/include/asm/dma-mapping.h
@@ -0,0 +1,140 @@
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of this
+ * archive for more details.
+ */
+
+#ifndef _ASM_NIOS2_DMA_MAPPING_H
+#define _ASM_NIOS2_DMA_MAPPING_H
+
+#include <linux/scatterlist.h>
+#include <linux/cache.h>
+#include <asm/cacheflush.h>
+
+static inline void __dma_sync_for_device(void *vaddr, size_t size,
+			      enum dma_data_direction direction)
+{
+	switch (direction) {
+	case DMA_FROM_DEVICE:
+		invalidate_dcache_range((unsigned long)vaddr,
+			(unsigned long)(vaddr + size));
+		break;
+	case DMA_TO_DEVICE:
+		/*
+		 * We just need to flush the caches here , but Nios2 flush
+		 * instruction will do both writeback and invalidate.
+		 */
+	case DMA_BIDIRECTIONAL: /* flush and invalidate */
+		flush_dcache_range((unsigned long)vaddr,
+			(unsigned long)(vaddr + size));
+		break;
+	default:
+		BUG();
+	}
+}
+
+static inline void __dma_sync_for_cpu(void *vaddr, size_t size,
+			      enum dma_data_direction direction)
+{
+	switch (direction) {
+	case DMA_BIDIRECTIONAL:
+	case DMA_FROM_DEVICE:
+		invalidate_dcache_range((unsigned long)vaddr,
+			(unsigned long)(vaddr + size));
+		break;
+	case DMA_TO_DEVICE:
+		break;
+	default:
+		BUG();
+	}
+}
+
+#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)
+
+void *dma_alloc_coherent(struct device *dev, size_t size,
+			   dma_addr_t *dma_handle, gfp_t flag);
+
+void dma_free_coherent(struct device *dev, size_t size,
+			 void *vaddr, dma_addr_t dma_handle);
+
+static inline dma_addr_t dma_map_single(struct device *dev, void *ptr,
+					size_t size,
+					enum dma_data_direction direction)
+{
+	BUG_ON(!valid_dma_direction(direction));
+	__dma_sync_for_device(ptr, size, direction);
+	return virt_to_phys(ptr);
+}
+
+static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
+				size_t size, enum dma_data_direction direction)
+{
+}
+
+extern int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+	enum dma_data_direction direction);
+extern dma_addr_t dma_map_page(struct device *dev, struct page *page,
+	unsigned long offset, size_t size, enum dma_data_direction direction);
+extern void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
+	size_t size, enum dma_data_direction direction);
+extern void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
+	int nhwentries, enum dma_data_direction direction);
+extern void dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
+	size_t size, enum dma_data_direction direction);
+extern void dma_sync_single_for_device(struct device *dev,
+	dma_addr_t dma_handle, size_t size, enum dma_data_direction direction);
+extern 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);
+extern 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);
+extern void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
+	int nelems, enum dma_data_direction direction);
+extern void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+	int nelems, enum dma_data_direction direction);
+
+static inline int dma_supported(struct device *dev, u64 mask)
+{
+	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_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+	return 0;
+}
+
+/*
+* dma_alloc_noncoherent() returns non-cacheable memory, so there's no need to
+* do any flushing here.
+*/
+static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
+				  enum dma_data_direction direction)
+{
+}
+
+/* drivers/base/dma-mapping.c */
+extern int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
+		void *cpu_addr, dma_addr_t dma_addr, size_t size);
+extern int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
+		void *cpu_addr, dma_addr_t dma_addr,
+		size_t size);
+
+#define dma_mmap_coherent(d, v, c, h, s) dma_common_mmap(d, v, c, h, s)
+#define dma_get_sgtable(d, t, v, h, s) dma_common_get_sgtable(d, t, v, h, s)
+
+#endif /* _ASM_NIOS2_DMA_MAPPING_H */