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-rw-r--r--arch/sh/kernel/dma-coherent.c84
1 files changed, 84 insertions, 0 deletions
diff --git a/arch/sh/kernel/dma-coherent.c b/arch/sh/kernel/dma-coherent.c
new file mode 100644
index 000000000000..2518065d5d27
--- /dev/null
+++ b/arch/sh/kernel/dma-coherent.c
@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2004 - 2007 Paul Mundt
+ *
+ * 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/mm.h>
+#include <linux/init.h>
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <asm/cacheflush.h>
+#include <asm/addrspace.h>
+
+void *dma_generic_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t gfp,
+ unsigned long attrs)
+{
+ void *ret, *ret_nocache;
+ int order = get_order(size);
+
+ gfp |= __GFP_ZERO;
+
+ ret = (void *)__get_free_pages(gfp, order);
+ if (!ret)
+ return NULL;
+
+ /*
+ * Pages from the page allocator may have data present in
+ * cache. So flush the cache before using uncached memory.
+ */
+ sh_sync_dma_for_device(ret, size, DMA_BIDIRECTIONAL);
+
+ ret_nocache = (void __force *)ioremap_nocache(virt_to_phys(ret), size);
+ if (!ret_nocache) {
+ free_pages((unsigned long)ret, order);
+ return NULL;
+ }
+
+ split_page(pfn_to_page(virt_to_phys(ret) >> PAGE_SHIFT), order);
+
+ *dma_handle = virt_to_phys(ret);
+ if (!WARN_ON(!dev))
+ *dma_handle -= PFN_PHYS(dev->dma_pfn_offset);
+
+ return ret_nocache;
+}
+
+void dma_generic_free_coherent(struct device *dev, size_t size,
+ void *vaddr, dma_addr_t dma_handle,
+ unsigned long attrs)
+{
+ int order = get_order(size);
+ unsigned long pfn = (dma_handle >> PAGE_SHIFT);
+ int k;
+
+ if (!WARN_ON(!dev))
+ pfn += dev->dma_pfn_offset;
+
+ for (k = 0; k < (1 << order); k++)
+ __free_pages(pfn_to_page(pfn + k), 0);
+
+ iounmap(vaddr);
+}
+
+void sh_sync_dma_for_device(void *vaddr, size_t size,
+ enum dma_data_direction direction)
+{
+ void *addr = sh_cacheop_vaddr(vaddr);
+
+ switch (direction) {
+ case DMA_FROM_DEVICE: /* invalidate only */
+ __flush_invalidate_region(addr, size);
+ break;
+ case DMA_TO_DEVICE: /* writeback only */
+ __flush_wback_region(addr, size);
+ break;
+ case DMA_BIDIRECTIONAL: /* writeback and invalidate */
+ __flush_purge_region(addr, size);
+ break;
+ default:
+ BUG();
+ }
+}