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}
108