[linux-2.6-block.git] / arch / cris / arch-v32 / drivers / pci / dma.c

/*
 * Dynamic DMA mapping support.
 *
 * On cris there is no hardware dynamic DMA address translation,
 * so consistent alloc/free are merely page allocation/freeing.
 * The rest of the dynamic DMA mapping interface is implemented
 * in asm/pci.h.
 *
 * Borrowed from i386.
 */

#include <linux/types.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/pci.h>
#include <asm/io.h>

struct dma_coherent_mem {
	void		*virt_base;
	u32		device_base;
	int		size;
	int		flags;
	unsigned long	*bitmap;
};

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);
	/* ignore region specifiers */
	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);

	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;
	}

	if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
		gfp |= GFP_DMA;

	ret = (void *)__get_free_pages(gfp, order);

	if (ret != NULL) {
		memset(ret, 0, size);
		*dma_handle = virt_to_phys(ret);
	}
	return ret;
}

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);

	if (mem && vaddr >= mem->virt_base && vaddr < (mem->virt_base + (mem->size << PAGE_SHIFT))) {
		int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;

		bitmap_release_region(mem->bitmap, page, order);
	} else
		free_pages((unsigned long)vaddr, order);
}

int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
				dma_addr_t device_addr, size_t size, int flags)
{
	void __iomem *mem_base;
	int pages = size >> PAGE_SHIFT;
	int bitmap_size = (pages + 31)/32;

	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(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;
	memset(dev->dma_mem, 0, sizeof(struct dma_coherent_mem));
	dev->dma_mem->bitmap = kmalloc(bitmap_size, GFP_KERNEL);
	if (!dev->dma_mem->bitmap)
		goto free1_out;
	memset(dev->dma_mem->bitmap, 0, bitmap_size);

	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->bitmap);
 out:
	return 0;
}
EXPORT_SYMBOL(dma_declare_coherent_memory);

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);

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(dma_mark_declared_memory_occupied);
Commit	Line	Data
51533b61 MS	1	/*
	2	* Dynamic DMA mapping support.
	3	*
	4	* On cris there is no hardware dynamic DMA address translation,
	5	* so consistent alloc/free are merely page allocation/freeing.
	6	* The rest of the dynamic DMA mapping interface is implemented
	7	* in asm/pci.h.
	8	*
	9	* Borrowed from i386.
	10	*/
	11
	12	#include <linux/types.h>
	13	#include <linux/mm.h>
	14	#include <linux/string.h>
	15	#include <linux/pci.h>
	16	#include <asm/io.h>
	17
	18	struct dma_coherent_mem {
	19	void *virt_base;
	20	u32 device_base;
	21	int size;
	22	int flags;
	23	unsigned long *bitmap;
	24	};
	25
	26	void dma_alloc_coherent(struct device dev, size_t size,
dd0fc66f	27	dma_addr_t *dma_handle, gfp_t gfp)
51533b61 MS	28	{
	29	void *ret;
	30	struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
	31	int order = get_order(size);
	32	/* ignore region specifiers */
	33	gfp &= ~(__GFP_DMA \| __GFP_HIGHMEM);
	34
	35	if (mem) {
	36	int page = bitmap_find_free_region(mem->bitmap, mem->size,
	37	order);
	38	if (page >= 0) {
	39	*dma_handle = mem->device_base + (page << PAGE_SHIFT);
	40	ret = mem->virt_base + (page << PAGE_SHIFT);
	41	memset(ret, 0, size);
	42	return ret;
	43	}
	44	if (mem->flags & DMA_MEMORY_EXCLUSIVE)
	45	return NULL;
	46	}
	47
	48	if (dev == NULL \|\| (dev->coherent_dma_mask < 0xffffffff))
	49	gfp \|= GFP_DMA;
	50
	51	ret = (void *)__get_free_pages(gfp, order);
	52
	53	if (ret != NULL) {
	54	memset(ret, 0, size);
	55	*dma_handle = virt_to_phys(ret);
	56	}
	57	return ret;
	58	}
	59
	60	void dma_free_coherent(struct device *dev, size_t size,
	61	void *vaddr, dma_addr_t dma_handle)
	62	{
	63	struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
	64	int order = get_order(size);
	65
	66	if (mem && vaddr >= mem->virt_base && vaddr < (mem->virt_base + (mem->size << PAGE_SHIFT))) {
	67	int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
	68
	69	bitmap_release_region(mem->bitmap, page, order);
	70	} else
	71	free_pages((unsigned long)vaddr, order);
	72	}
	73
	74	int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
	75	dma_addr_t device_addr, size_t size, int flags)
	76	{
	77	void __iomem *mem_base;
	78	int pages = size >> PAGE_SHIFT;
	79	int bitmap_size = (pages + 31)/32;
	80
	81	if ((flags & (DMA_MEMORY_MAP \| DMA_MEMORY_IO)) == 0)
	82	goto out;
	83	if (!size)
	84	goto out;
	85	if (dev->dma_mem)
	86	goto out;
	87
	88	/* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
	89
	90	mem_base = ioremap(bus_addr, size);
	91	if (!mem_base)
92	goto out;
93
94	dev->dma_mem = kmalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
95	if (!dev->dma_mem)
96	goto out;
97	memset(dev->dma_mem, 0, sizeof(struct dma_coherent_mem));
98	dev->dma_mem->bitmap = kmalloc(bitmap_size, GFP_KERNEL);
99	if (!dev->dma_mem->bitmap)
100	goto free1_out;
101	memset(dev->dma_mem->bitmap, 0, bitmap_size);
102
103	dev->dma_mem->virt_base = mem_base;
104	dev->dma_mem->device_base = device_addr;
105	dev->dma_mem->size = pages;
106	dev->dma_mem->flags = flags;
107
108	if (flags & DMA_MEMORY_MAP)
109	return DMA_MEMORY_MAP;
110
111	return DMA_MEMORY_IO;
112
113	free1_out:
114	kfree(dev->dma_mem->bitmap);
115	out:
116	return 0;
117	}
118	EXPORT_SYMBOL(dma_declare_coherent_memory);
119
120	void dma_release_declared_memory(struct device *dev)
121	{
122	struct dma_coherent_mem *mem = dev->dma_mem;
123
124	if(!mem)
125	return;
126	dev->dma_mem = NULL;
127	iounmap(mem->virt_base);
128	kfree(mem->bitmap);
129	kfree(mem);
130	}
131	EXPORT_SYMBOL(dma_release_declared_memory);
132
133	void dma_mark_declared_memory_occupied(struct device dev,
134	dma_addr_t device_addr, size_t size)
135	{
136	struct dma_coherent_mem *mem = dev->dma_mem;
137	int pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1) >> PAGE_SHIFT;
138	int pos, err;
139
140	if (!mem)
141	return ERR_PTR(-EINVAL);
142
143	pos = (device_addr - mem->device_base) >> PAGE_SHIFT;
144	err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages));
145	if (err != 0)
146	return ERR_PTR(err);
147	return mem->virt_base + (pos << PAGE_SHIFT);
148	}
149	EXPORT_SYMBOL(dma_mark_declared_memory_occupied);