1 files changed, 183 insertions, 0 deletions

diff --git a/arch/blackfin/kernel/dma-mapping.c b/arch/blackfin/kernel/dma-mapping.c
new file mode 100644
index 000000000000..539eb24e062f
--- /dev/null
+++ b/arch/blackfin/kernel/dma-mapping.c
@@ -0,0 +1,183 @@
+/*
+ * File:         arch/blackfin/kernel/dma-mapping.c
+ * Based on:
+ * Author:
+ *
+ * Created:
+ * Description:  Dynamic DMA mapping support.
+ *
+ * Modified:
+ *               Copyright 2004-2006 Analog Devices Inc.
+ *
+ * Bugs:         Enter bugs at http://blackfin.uclinux.org/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/bootmem.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <asm/cacheflush.h>
+#include <asm/io.h>
+#include <asm/bfin-global.h>
+
+static spinlock_t dma_page_lock;
+static unsigned int *dma_page;
+static unsigned int dma_pages;
+static unsigned long dma_base;
+static unsigned long dma_size;
+static unsigned int dma_initialized;
+
+void dma_alloc_init(unsigned long start, unsigned long end)
+{
+        spin_lock_init(&dma_page_lock);
+        dma_initialized = 0;
+
+        dma_page = (unsigned int *)__get_free_page(GFP_KERNEL);
+        memset(dma_page, 0, PAGE_SIZE);
+        dma_base = PAGE_ALIGN(start);
+        dma_size = PAGE_ALIGN(end) - PAGE_ALIGN(start);
+        dma_pages = dma_size >> PAGE_SHIFT;
+        memset((void *)dma_base, 0, DMA_UNCACHED_REGION);
+        dma_initialized = 1;
+
+        printk(KERN_INFO "%s: dma_page @ 0x%p - %d pages at 0x%08lx\n", __FUNCTION__,
+               dma_page, dma_pages, dma_base);
+}
+
+static inline unsigned int get_pages(size_t size)
+{
+        return ((size - 1) >> PAGE_SHIFT) + 1;
+}
+
+static unsigned long __alloc_dma_pages(unsigned int pages)
+{
+        unsigned long ret = 0, flags;
+        int i, count = 0;
+
+        if (dma_initialized == 0)
+                dma_alloc_init(_ramend - DMA_UNCACHED_REGION, _ramend);
+
+        spin_lock_irqsave(&dma_page_lock, flags);
+
+        for (i = 0; i < dma_pages;) {
+                if (dma_page[i++] == 0) {
+                        if (++count == pages) {
+                                while (count--)
+                                        dma_page[--i] = 1;
+                                ret = dma_base + (i << PAGE_SHIFT);
+                                break;
+                        }
+                } else
+                        count = 0;
+        }
+        spin_unlock_irqrestore(&dma_page_lock, flags);
+        return ret;
+}
+
+static void __free_dma_pages(unsigned long addr, unsigned int pages)
+{
+        unsigned long page = (addr - dma_base) >> PAGE_SHIFT;
+        unsigned long flags;
+        int i;
+
+        if ((page + pages) > dma_pages) {
+                printk(KERN_ERR "%s: freeing outside range.\n", __FUNCTION__);
+                BUG();
+        }
+
+        spin_lock_irqsave(&dma_page_lock, flags);
+        for (i = page; i < page + pages; i++) {
+                dma_page[i] = 0;
+        }
+        spin_unlock_irqrestore(&dma_page_lock, flags);
+}
+
+void *dma_alloc_coherent(struct device *dev, size_t size,
+                         dma_addr_t * dma_handle, gfp_t gfp)
+{
+        void *ret;
+
+        ret = (void *)__alloc_dma_pages(get_pages(size));
+
+        if (ret) {
+                memset(ret, 0, size);
+                *dma_handle = virt_to_phys(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)
+{
+        __free_dma_pages((unsigned long)vaddr, get_pages(size));
+}
+EXPORT_SYMBOL(dma_free_coherent);
+
+/*
+ * Dummy functions defined for some existing drivers
+ */
+
+dma_addr_t
+dma_map_single(struct device *dev, void *ptr, size_t size,
+               enum dma_data_direction direction)
+{
+        BUG_ON(direction == DMA_NONE);
+
+        invalidate_dcache_range((unsigned long)ptr,
+                        (unsigned long)ptr + size);
+
+        return (dma_addr_t) ptr;
+}
+EXPORT_SYMBOL(dma_map_single);
+
+int
+dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+           enum dma_data_direction direction)
+{
+        int i;
+
+        BUG_ON(direction == DMA_NONE);
+
+        for (i = 0; i < nents; i++)
+                invalidate_dcache_range(sg_dma_address(&sg[i]),
+                                        sg_dma_address(&sg[i]) +
+                                        sg_dma_len(&sg[i]));
+
+        return nents;
+}
+EXPORT_SYMBOL(dma_map_sg);
+
+void dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
+                enum dma_data_direction direction)
+{
+        BUG_ON(direction == DMA_NONE);
+}
+EXPORT_SYMBOL(dma_unmap_single);
+
+void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
+                int nhwentries, enum dma_data_direction direction)
+{
+        BUG_ON(direction == DMA_NONE);
+}
+EXPORT_SYMBOL(dma_unmap_sg);