[PATCH] m68k: Add the generic dma API functions

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 131 insertions, 2 deletions

diff --git a/arch/m68k/kernel/Makefile b/arch/m68k/kernel/Makefile
index 458925c471a1..dae609797dc0 100644
--- a/arch/m68k/kernel/Makefile
+++ b/arch/m68k/kernel/Makefile
@@ -9,8 +9,8 @@ else
 endif
 extra-y += vmlinux.lds
 
-obj-y           := entry.o process.o traps.o ints.o signal.o ptrace.o \
-                        sys_m68k.o time.o semaphore.o setup.o m68k_ksyms.o
+obj-y   := entry.o process.o traps.o ints.o dma.o signal.o ptrace.o \
+           sys_m68k.o time.o semaphore.o setup.o m68k_ksyms.o
 
 obj-$(CONFIG_PCI)       += bios32.o
 obj-$(CONFIG_MODULES)   += module.o
diff --git a/arch/m68k/kernel/dma.c b/arch/m68k/kernel/dma.c
new file mode 100644
index 000000000000..fc449f8b2045
--- /dev/null
+++ b/arch/m68k/kernel/dma.c
@@ -0,0 +1,129 @@
+/*
+ * 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.
+ */
+
+#undef DEBUG
+
+#include <linux/dma-mapping.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/vmalloc.h>
+
+#include <asm/pgalloc.h>
+#include <asm/scatterlist.h>
+
+void *dma_alloc_coherent(struct device *dev, size_t size,
+                         dma_addr_t *handle, int flag)
+{
+        struct page *page, **map;
+        pgprot_t pgprot;
+        void *addr;
+        int i, order;
+
+        pr_debug("dma_alloc_coherent: %d,%x\n", size, flag);
+
+        size = PAGE_ALIGN(size);
+        order = get_order(size);
+
+        page = alloc_pages(flag, order);
+        if (!page)
+                return NULL;
+
+        *handle = page_to_phys(page);
+        map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA);
+        if (!map) {
+                __free_pages(page, order);
+                return NULL;
+        }
+        split_page(page, order);
+
+        order = 1 << order;
+        size >>= PAGE_SHIFT;
+        map[0] = page;
+        for (i = 1; i < size; i++)
+                map[i] = page + i;
+        for (; i < order; i++)
+                __free_page(page + i);
+        pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
+        if (CPU_IS_040_OR_060)
+                pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
+        else
+                pgprot_val(pgprot) |= _PAGE_NOCACHE030;
+        addr = vmap(map, size, flag, pgprot);
+        kfree(map);
+
+        return addr;
+}
+EXPORT_SYMBOL(dma_alloc_coherent);
+
+void dma_free_coherent(struct device *dev, size_t size,
+                       void *addr, dma_addr_t handle)
+{
+        pr_debug("dma_free_coherent: %p, %x\n", addr, handle);
+        vfree(addr);
+}
+EXPORT_SYMBOL(dma_free_coherent);
+
+inline void dma_sync_single_for_device(struct device *dev, dma_addr_t handle, size_t size,
+                                       enum dma_data_direction dir)
+{
+        switch (dir) {
+        case DMA_TO_DEVICE:
+                cache_push(handle, size);
+                break;
+        case DMA_FROM_DEVICE:
+                cache_clear(handle, size);
+                break;
+        default:
+                if (printk_ratelimit())
+                        printk("dma_sync_single_for_device: unsupported dir %u\n", dir);
+                break;
+        }
+}
+EXPORT_SYMBOL(dma_sync_single_for_device);
+
+void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents,
+                            enum dma_data_direction dir)
+{
+        int i;
+
+        for (i = 0; i < nents; sg++, i++)
+                dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
+}
+EXPORT_SYMBOL(dma_sync_sg_for_device);
+
+dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size,
+                          enum dma_data_direction dir)
+{
+        dma_addr_t handle = virt_to_bus(addr);
+
+        dma_sync_single_for_device(dev, handle, size, dir);
+        return handle;
+}
+EXPORT_SYMBOL(dma_map_single);
+
+dma_addr_t dma_map_page(struct device *dev, struct page *page,
+                        unsigned long offset, size_t size,
+                        enum dma_data_direction dir)
+{
+        dma_addr_t handle = page_to_phys(page) + offset;
+
+        dma_sync_single_for_device(dev, handle, size, dir);
+        return handle;
+}
+EXPORT_SYMBOL(dma_map_page);
+
+int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+               enum dma_data_direction dir)
+{
+        int i;
+
+        for (i = 0; i < nents; sg++, i++) {
+                sg->dma_address = page_to_phys(sg->page) + sg->offset;
+                dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
+        }
+        return nents;
+}
+EXPORT_SYMBOL(dma_map_sg);