arm64: DMA mapping API

/*

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * 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 <http://www.gnu.org/licenses/>.

 */

#ifndef __ASM_DMA_MAPPING_H

#define __ASM_DMA_MAPPING_H

#ifdef __KERNEL__

#include <linux/types.h>

#include <linux/vmalloc.h>

#include <asm-generic/dma-coherent.h>

#define ARCH_HAS_DMA_GET_REQUIRED_MASK

extern struct dma_map_ops *dma_ops;

static inline struct dma_map_ops *get_dma_ops(struct device *dev)

{

	if (unlikely(!dev) || !dev->archdata.dma_ops)

		return dma_ops;

	else

		return dev->archdata.dma_ops;

}

#include <asm-generic/dma-mapping-common.h>

static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)

{

	return (dma_addr_t)paddr;

}

static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)

{

	return (phys_addr_t)dev_addr;

}

static inline int dma_mapping_error(struct device *dev, dma_addr_t dev_addr)

{

	struct dma_map_ops *ops = get_dma_ops(dev);

	return ops->mapping_error(dev, dev_addr);

}

static inline int dma_supported(struct device *dev, u64 mask)

{

	struct dma_map_ops *ops = get_dma_ops(dev);

	return ops->dma_supported(dev, mask);

}

static inline int dma_set_mask(struct device *dev, u64 mask)

{

	if (!dev->dma_mask || !dma_supported(dev, mask))

		return -EIO;

	*dev->dma_mask = mask;

	return 0;

}

static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)

{

	if (!dev->dma_mask)

		return 0;

	return addr + size - 1 <= *dev->dma_mask;

}

static inline void dma_mark_clean(void *addr, size_t size)

{

}

static inline void *dma_alloc_coherent(struct device *dev, size_t size,

				       dma_addr_t *dma_handle, gfp_t flags)

{

	struct dma_map_ops *ops = get_dma_ops(dev);

	void *vaddr;

	if (dma_alloc_from_coherent(dev, size, dma_handle, &vaddr))

		return vaddr;

	vaddr = ops->alloc(dev, size, dma_handle, flags, NULL);

	debug_dma_alloc_coherent(dev, size, *dma_handle, vaddr);

	return vaddr;

}

static inline void dma_free_coherent(struct device *dev, size_t size,

				     void *vaddr, dma_addr_t dev_addr)

{

	struct dma_map_ops *ops = get_dma_ops(dev);

	if (dma_release_from_coherent(dev, get_order(size), vaddr))

		return;

	debug_dma_free_coherent(dev, size, vaddr, dev_addr);

	ops->free(dev, size, vaddr, dev_addr, NULL);

}

/*

 * There is no dma_cache_sync() implementation, so just return NULL here.

 */

static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,

					  dma_addr_t *handle, gfp_t flags)

{

	return NULL;

}

static inline void dma_free_noncoherent(struct device *dev, size_t size,

					void *cpu_addr, dma_addr_t handle)

{

}

#endif	/* __KERNEL__ */

#endif	/* __ASM_DMA_MAPPING_H */

/*

 * SWIOTLB-based DMA API implementation

 *

 * Copyright (C) 2012 ARM Ltd.

 * Author: Catalin Marinas <catalin.marinas@arm.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * 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 <http://www.gnu.org/licenses/>.

 */

#include <linux/gfp.h>

#include <linux/export.h>

#include <linux/slab.h>

#include <linux/dma-mapping.h>

#include <linux/vmalloc.h>

#include <linux/swiotlb.h>

#include <asm/cacheflush.h>

struct dma_map_ops *dma_ops;

EXPORT_SYMBOL(dma_ops);

static void *arm64_swiotlb_alloc_coherent(struct device *dev, size_t size,

					  dma_addr_t *dma_handle, gfp_t flags,

					  struct dma_attrs *attrs)

{

	if (IS_ENABLED(CONFIG_ZONE_DMA32) &&

	    dev->coherent_dma_mask <= DMA_BIT_MASK(32))

		flags |= GFP_DMA32;

	return swiotlb_alloc_coherent(dev, size, dma_handle, flags);

}

static void arm64_swiotlb_free_coherent(struct device *dev, size_t size,

					void *vaddr, dma_addr_t dma_handle,

					struct dma_attrs *attrs)

{

	swiotlb_free_coherent(dev, size, vaddr, dma_handle);

}

static struct dma_map_ops arm64_swiotlb_dma_ops = {

	.alloc = arm64_swiotlb_alloc_coherent,

	.free = arm64_swiotlb_free_coherent,

	.map_page = swiotlb_map_page,

	.unmap_page = swiotlb_unmap_page,

	.map_sg = swiotlb_map_sg_attrs,

	.unmap_sg = swiotlb_unmap_sg_attrs,

	.sync_single_for_cpu = swiotlb_sync_single_for_cpu,

	.sync_single_for_device = swiotlb_sync_single_for_device,

	.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,

	.sync_sg_for_device = swiotlb_sync_sg_for_device,

	.dma_supported = swiotlb_dma_supported,

	.mapping_error = swiotlb_dma_mapping_error,

};

void __init swiotlb_init_with_default_size(size_t default_size, int verbose);

void __init arm64_swiotlb_init(size_t max_size)

{

	dma_ops = &arm64_swiotlb_dma_ops;

	swiotlb_init_with_default_size(min((size_t)SZ_64M, max_size), 1);

}

#define PREALLOC_DMA_DEBUG_ENTRIES	4096

static int __init dma_debug_do_init(void)

{

	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);

	return 0;

}

fs_initcall(dma_debug_do_init);