1 files changed, 128 insertions, 46 deletions

diff --git a/arch/sh/mm/consistent.c b/arch/sh/mm/consistent.c
index 65ad30031ad7..7b2131c9eeda 100644
--- a/arch/sh/mm/consistent.c
+++ b/arch/sh/mm/consistent.c
@@ -3,6 +3,8 @@
  *
  * Copyright (C) 2004 - 2007  Paul Mundt
  *
+ * Declared coherent memory functions based on arch/x86/kernel/pci-dma_32.c
+ *
  * 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.
@@ -13,66 +15,146 @@
 #include <asm/addrspace.h>
 #include <asm/io.h>
 
-void *consistent_alloc(gfp_t gfp, size_t size, dma_addr_t *handle)
-{
-        struct page *page, *end, *free;
-        void *ret, *vp;
-        int order;
-
-        size = PAGE_ALIGN(size);
-        order = get_order(size);
+struct dma_coherent_mem {
+        void            *virt_base;
+        u32             device_base;
+        int             size;
+        int             flags;
+        unsigned long   *bitmap;
+};
 
-        page = alloc_pages(gfp, order);
-        if (!page)
-                return NULL;
-        split_page(page, order);
+void *dma_alloc_coherent(struct device *dev, size_t size,
+                           dma_addr_t *dma_handle, gfp_t gfp)
+{
+        void *ret;
+        struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
+        int order = get_order(size);
+
+        if (mem) {
+                int page = bitmap_find_free_region(mem->bitmap, mem->size,
+                                                     order);
+                if (page >= 0) {
+                        *dma_handle = mem->device_base + (page << PAGE_SHIFT);
+                        ret = mem->virt_base + (page << PAGE_SHIFT);
+                        memset(ret, 0, size);
+                        return ret;
+                }
+                if (mem->flags & DMA_MEMORY_EXCLUSIVE)
+                        return NULL;
+        }
 
-        ret = page_address(page);
-        *handle = virt_to_phys(ret);
+        ret = (void *)__get_free_pages(gfp, order);
 
-        vp = ioremap_nocache(*handle, size);
-        if (!vp) {
-                free_pages((unsigned long)ret, order);
-                return NULL;
+        if (ret != NULL) {
+                memset(ret, 0, size);
+                /*
+                 * Pages from the page allocator may have data present in
+                 * cache. So flush the cache before using uncached memory.
+                 */
+                dma_cache_sync(NULL, ret, size, DMA_BIDIRECTIONAL);
+                *dma_handle = virt_to_phys(ret);
         }
+        return ret;
+}
+EXPORT_SYMBOL(dma_alloc_coherent);
 
-        memset(vp, 0, size);
-
-        /*
-         * We must flush the cache before we pass it on to the device
-         */
-        dma_cache_sync(NULL, ret, size, DMA_BIDIRECTIONAL);
+void dma_free_coherent(struct device *dev, size_t size,
+                         void *vaddr, dma_addr_t dma_handle)
+{
+        struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
+        int order = get_order(size);
 
-        page = virt_to_page(ret);
-        free = page + (size >> PAGE_SHIFT);
-        end  = page + (1 << order);
+        if (mem && vaddr >= mem->virt_base && vaddr < (mem->virt_base + (mem->size << PAGE_SHIFT))) {
+                int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
 
-        while (++page < end) {
-                /* Free any unused pages */
-                if (page >= free) {
-                        __free_page(page);
-                }
+                bitmap_release_region(mem->bitmap, page, order);
+        } else {
+                WARN_ON(irqs_disabled());       /* for portability */
+                BUG_ON(mem && mem->flags & DMA_MEMORY_EXCLUSIVE);
+                free_pages((unsigned long)vaddr, order);
         }
-
-        return vp;
 }
-EXPORT_SYMBOL(consistent_alloc);
+EXPORT_SYMBOL(dma_free_coherent);
 
-void consistent_free(void *vaddr, size_t size, dma_addr_t dma_handle)
+int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+                                dma_addr_t device_addr, size_t size, int flags)
 {
-        struct page *page;
-        unsigned long addr;
-
-        addr = (unsigned long)phys_to_virt((unsigned long)dma_handle);
-        page = virt_to_page(addr);
+        void __iomem *mem_base = NULL;
+        int pages = size >> PAGE_SHIFT;
+        int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
+
+        if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0)
+                goto out;
+        if (!size)
+                goto out;
+        if (dev->dma_mem)
+                goto out;
+
+        /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
+
+        mem_base = ioremap_nocache(bus_addr, size);
+        if (!mem_base)
+                goto out;
+
+        dev->dma_mem = kmalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
+        if (!dev->dma_mem)
+                goto out;
+        dev->dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
+        if (!dev->dma_mem->bitmap)
+                goto free1_out;
+
+        dev->dma_mem->virt_base = mem_base;
+        dev->dma_mem->device_base = device_addr;
+        dev->dma_mem->size = pages;
+        dev->dma_mem->flags = flags;
+
+        if (flags & DMA_MEMORY_MAP)
+                return DMA_MEMORY_MAP;
+
+        return DMA_MEMORY_IO;
+
+ free1_out:
+        kfree(dev->dma_mem);
+ out:
+        if (mem_base)
+                iounmap(mem_base);
+        return 0;
+}
+EXPORT_SYMBOL(dma_declare_coherent_memory);
 
-        free_pages(addr, get_order(size));
+void dma_release_declared_memory(struct device *dev)
+{
+        struct dma_coherent_mem *mem = dev->dma_mem;
+
+        if (!mem)
+                return;
+        dev->dma_mem = NULL;
+        iounmap(mem->virt_base);
+        kfree(mem->bitmap);
+        kfree(mem);
+}
+EXPORT_SYMBOL(dma_release_declared_memory);
 
-        iounmap(vaddr);
+void *dma_mark_declared_memory_occupied(struct device *dev,
+                                        dma_addr_t device_addr, size_t size)
+{
+        struct dma_coherent_mem *mem = dev->dma_mem;
+        int pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1) >> PAGE_SHIFT;
+        int pos, err;
+
+        if (!mem)
+                return ERR_PTR(-EINVAL);
+
+        pos = (device_addr - mem->device_base) >> PAGE_SHIFT;
+        err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages));
+        if (err != 0)
+                return ERR_PTR(err);
+        return mem->virt_base + (pos << PAGE_SHIFT);
 }
-EXPORT_SYMBOL(consistent_free);
+EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
 
-void consistent_sync(void *vaddr, size_t size, int direction)
+void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
+                    enum dma_data_direction direction)
 {
 #ifdef CONFIG_CPU_SH5
         void *p1addr = vaddr;
@@ -94,4 +176,4 @@ void consistent_sync(void *vaddr, size_t size, int direction)
                 BUG();
         }
 }
-EXPORT_SYMBOL(consistent_sync);
+EXPORT_SYMBOL(dma_cache_sync);