[PATCH v2 13/29] nios2: DMA mapping API

Ley Foon Tan
2014-07-15T08:52:05Z

This patch adds support for the DMA mapping API.

Signed-off-by: Ley Foon Tan <lftan@altera.com>
---
arch/nios2/include/asm/dma-mapping.h | 106 ++++++++++++++++++++
arch/nios2/mm/dma-mapping.c | 186 +++++++++++++++++++++++++++++++++++
2 files changed, 292 insertions(+)
create mode 100644 arch/nios2/include/asm/dma-mapping.h
create mode 100644 arch/nios2/mm/dma-mapping.c

diff --git a/arch/nios2/include/asm/dma-mapping.h b/arch/nios2/include/asm/dma-mapping.h
new file mode 100644
index 0000000..2db7ac3
--- /dev/null
+++ b/arch/nios2/include/asm/dma-mapping.h
@@ -0,0 +1,106 @@
+/*
+ * 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(void *vaddr, size_t size,
+ enum dma_data_direction direction)
+{
+ switch (direction) {
+ case DMA_FROM_DEVICE: /* invalidate cache */
+ invalidate_dcache_range((unsigned long)vaddr,
+ (unsigned long)(vaddr + size));
+ break;
+ case DMA_TO_DEVICE: /* flush and invalidate cache */
+ case DMA_BIDIRECTIONAL:
+ flush_dcache_range((unsigned long)vaddr,
+ (unsigned long)(vaddr + size));
+ 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)
+{
+ __dma_sync(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;
+}
+
+static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
+ enum dma_data_direction direction)
+{
+ __dma_sync(vaddr, size, direction);
+}
+
+#endif /* _ASM_NIOS2_DMA_MAPPING_H */
diff --git a/arch/nios2/mm/dma-mapping.c b/arch/nios2/mm/dma-mapping.c
new file mode 100644
index 0000000..a9bafe9
--- /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(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(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));
+
+ if (direction != DMA_TO_DEVICE)
+ __dma_sync(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(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(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(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(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(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(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(sg_virt(sg), sg->length, direction);
+
+}
+EXPORT_SYMBOL(dma_sync_sg_for_device);
--
1.8.2.1