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, 186 insertions, 0 deletions

diff --git a/arch/nios2/mm/dma-mapping.c b/arch/nios2/mm/dma-mapping.c
new file mode 100644
index 000000000000..ac5da7594f0b
--- /dev/null
+++ b/arch/nios2/mm/dma-mapping.c
@@ -0,0 +1,186 @@
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ *  Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ *
+ * Based on DMA code from MIPS.
+ *
+ * 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.
+ */
+
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/export.h>
+#include <linux/string.h>
+#include <linux/scatterlist.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/cache.h>
+#include <asm/cacheflush.h>
+
+
+void *dma_alloc_coherent(struct device *dev, size_t size,
+                            dma_addr_t *dma_handle, gfp_t gfp)
+{
+        void *ret;
+
+        /* ignore region specifiers */
+        gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
+
+        /* optimized page clearing */
+        gfp |= __GFP_ZERO;
+
+        if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
+                gfp |= GFP_DMA;
+
+        ret = (void *) __get_free_pages(gfp, get_order(size));
+        if (ret != NULL) {
+                *dma_handle = virt_to_phys(ret);
+                flush_dcache_range((unsigned long) ret,
+                        (unsigned long) ret + size);
+                ret = UNCAC_ADDR(ret);
+        }
+
+        return ret;
+}
+EXPORT_SYMBOL(dma_alloc_coherent);
+
+void dma_free_coherent(struct device *dev, size_t size, void *vaddr,
+                        dma_addr_t dma_handle)
+{
+        unsigned long addr = (unsigned long) CAC_ADDR((unsigned long) vaddr);
+
+        free_pages(addr, get_order(size));
+}
+EXPORT_SYMBOL(dma_free_coherent);
+
+int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+                enum dma_data_direction direction)
+{
+        int i;
+
+        BUG_ON(!valid_dma_direction(direction));
+
+        for_each_sg(sg, sg, nents, i) {
+                void *addr;
+
+                addr = sg_virt(sg);
+                if (addr) {
+                        __dma_sync_for_device(addr, sg->length, direction);
+                        sg->dma_address = sg_phys(sg);
+                }
+        }
+
+        return nents;
+}
+EXPORT_SYMBOL(dma_map_sg);
+
+dma_addr_t dma_map_page(struct device *dev, struct page *page,
+                        unsigned long offset, size_t size,
+                        enum dma_data_direction direction)
+{
+        void *addr;
+
+        BUG_ON(!valid_dma_direction(direction));
+
+        addr = page_address(page) + offset;
+        __dma_sync_for_device(addr, size, direction);
+
+        return page_to_phys(page) + offset;
+}
+EXPORT_SYMBOL(dma_map_page);
+
+void dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size,
+                    enum dma_data_direction direction)
+{
+        BUG_ON(!valid_dma_direction(direction));
+
+        __dma_sync_for_cpu(phys_to_virt(dma_address), size, direction);
+}
+EXPORT_SYMBOL(dma_unmap_page);
+
+void dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries,
+                  enum dma_data_direction direction)
+{
+        void *addr;
+        int i;
+
+        BUG_ON(!valid_dma_direction(direction));
+
+        if (direction == DMA_TO_DEVICE)
+                return;
+
+        for_each_sg(sg, sg, nhwentries, i) {
+                addr = sg_virt(sg);
+                if (addr)
+                        __dma_sync_for_cpu(addr, sg->length, direction);
+        }
+}
+EXPORT_SYMBOL(dma_unmap_sg);
+
+void dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
+                             size_t size, enum dma_data_direction direction)
+{
+        BUG_ON(!valid_dma_direction(direction));
+
+        __dma_sync_for_cpu(phys_to_virt(dma_handle), size, direction);
+}
+EXPORT_SYMBOL(dma_sync_single_for_cpu);
+
+void dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle,
+                                size_t size, enum dma_data_direction direction)
+{
+        BUG_ON(!valid_dma_direction(direction));
+
+        __dma_sync_for_device(phys_to_virt(dma_handle), size, direction);
+}
+EXPORT_SYMBOL(dma_sync_single_for_device);
+
+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)
+{
+        BUG_ON(!valid_dma_direction(direction));
+
+        __dma_sync_for_cpu(phys_to_virt(dma_handle), size, direction);
+}
+EXPORT_SYMBOL(dma_sync_single_range_for_cpu);
+
+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)
+{
+        BUG_ON(!valid_dma_direction(direction));
+
+        __dma_sync_for_device(phys_to_virt(dma_handle), size, direction);
+}
+EXPORT_SYMBOL(dma_sync_single_range_for_device);
+
+void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems,
+                         enum dma_data_direction direction)
+{
+        int i;
+
+        BUG_ON(!valid_dma_direction(direction));
+
+        /* Make sure that gcc doesn't leave the empty loop body.  */
+        for_each_sg(sg, sg, nelems, i)
+                __dma_sync_for_cpu(sg_virt(sg), sg->length, direction);
+}
+EXPORT_SYMBOL(dma_sync_sg_for_cpu);
+
+void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+                                int nelems, enum dma_data_direction direction)
+{
+        int i;
+
+        BUG_ON(!valid_dma_direction(direction));
+
+        /* Make sure that gcc doesn't leave the empty loop body.  */
+        for_each_sg(sg, sg, nelems, i)
+                __dma_sync_for_device(sg_virt(sg), sg->length, direction);
+
+}
+EXPORT_SYMBOL(dma_sync_sg_for_device);