*
* 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.
#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;
BUG();
}
}
-EXPORT_SYMBOL(consistent_sync);
+EXPORT_SYMBOL(dma_cache_sync);
projects / platform / kernel / linux-starfive.git / blobdiff