1/*
  2*  Copyright (C) 2003-2013 Broadcom Corporation
  3*  All Rights Reserved
  4 *
  5 * This software is available to you under a choice of one of two
  6 * licenses.  You may choose to be licensed under the terms of the GNU
  7 * General Public License (GPL) Version 2, available from the file
  8 * COPYING in the main directory of this source tree, or the Broadcom
  9 * license below:
 10 *
 11 * Redistribution and use in source and binary forms, with or without
 12 * modification, are permitted provided that the following conditions
 13 * are met:
 14 *
 15 * 1. Redistributions of source code must retain the above copyright
 16 *    notice, this list of conditions and the following disclaimer.
 17 * 2. Redistributions in binary form must reproduce the above copyright
 18 *    notice, this list of conditions and the following disclaimer in
 19 *    the documentation and/or other materials provided with the
 20 *    distribution.
 21 *
 22 * THIS SOFTWARE IS PROVIDED BY BROADCOM ``AS IS'' AND ANY EXPRESS OR
 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 24 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 25 * ARE DISCLAIMED. IN NO EVENT SHALL BROADCOM OR CONTRIBUTORS BE LIABLE
 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 29 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 30 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 31 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 32 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 33 */
 34#include <linux/dma-mapping.h>
 35#include <linux/scatterlist.h>
 36#include <linux/bootmem.h>
 37#include <linux/export.h>
 38#include <linux/swiotlb.h>
 39#include <linux/types.h>
 40#include <linux/init.h>
 41#include <linux/mm.h>
 42
 43#include <asm/bootinfo.h>
 44
 45static char *nlm_swiotlb;
 46
 47static void *nlm_dma_alloc_coherent(struct device *dev, size_t size,
 48	dma_addr_t *dma_handle, gfp_t gfp, struct dma_attrs *attrs)
 49{
 50	void *ret;
 51
 52	if (dma_alloc_from_coherent(dev, size, dma_handle, &ret))
 53		return ret;
 54
 55	/* ignore region specifiers */
 56	gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
 57
 58#ifdef CONFIG_ZONE_DMA32
 59	if (dev->coherent_dma_mask <= DMA_BIT_MASK(32))
 60		gfp |= __GFP_DMA32;
 61#endif
 62
 63	/* Don't invoke OOM killer */
 64	gfp |= __GFP_NORETRY;
 65
 66	return swiotlb_alloc_coherent(dev, size, dma_handle, gfp);
 67}
 68
 69static void nlm_dma_free_coherent(struct device *dev, size_t size,
 70	void *vaddr, dma_addr_t dma_handle, struct dma_attrs *attrs)
 71{
 72	int order = get_order(size);
 73
 74	if (dma_release_from_coherent(dev, order, vaddr))
 75		return;
 76
 77	swiotlb_free_coherent(dev, size, vaddr, dma_handle);
 78}
 79
 80struct dma_map_ops nlm_swiotlb_dma_ops = {
 81	.alloc = nlm_dma_alloc_coherent,
 82	.free = nlm_dma_free_coherent,
 83	.map_page = swiotlb_map_page,
 84	.unmap_page = swiotlb_unmap_page,
 85	.map_sg = swiotlb_map_sg_attrs,
 86	.unmap_sg = swiotlb_unmap_sg_attrs,
 87	.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
 88	.sync_single_for_device = swiotlb_sync_single_for_device,
 89	.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
 90	.sync_sg_for_device = swiotlb_sync_sg_for_device,
 91	.mapping_error = swiotlb_dma_mapping_error,
 92	.dma_supported = swiotlb_dma_supported
 93};
 94
 95void __init plat_swiotlb_setup(void)
 96{
 97	size_t swiotlbsize;
 98	unsigned long swiotlb_nslabs;
 99
100	swiotlbsize = 1 << 20; /* 1 MB for now */
101	swiotlb_nslabs = swiotlbsize >> IO_TLB_SHIFT;
102	swiotlb_nslabs = ALIGN(swiotlb_nslabs, IO_TLB_SEGSIZE);
103	swiotlbsize = swiotlb_nslabs << IO_TLB_SHIFT;
104
105	nlm_swiotlb = alloc_bootmem_low_pages(swiotlbsize);
106	swiotlb_init_with_tbl(nlm_swiotlb, swiotlb_nslabs, 1);
107}