4 * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
20 #include <linux/export.h>
21 #include <linux/limits.h>
23 #include <linux/of_iommu.h>
25 static const struct of_device_id __iommu_of_table_sentinel
26 __used __section(__iommu_of_table_end);
29 * of_get_dma_window - Parse *dma-window property and returns 0 if found.
32 * @prefix: prefix for property name if any
33 * @index: index to start to parse
34 * @busno: Returns busno if supported. Otherwise pass NULL
35 * @addr: Returns address that DMA starts
36 * @size: Returns the range that DMA can handle
38 * This supports different formats flexibly. "prefix" can be
39 * configured if any. "busno" and "index" are optionally
40 * specified. Set 0(or NULL) if not used.
42 int of_get_dma_window(struct device_node *dn, const char *prefix, int index,
43 unsigned long *busno, dma_addr_t *addr, size_t *size)
45 const __be32 *dma_window, *end;
46 int bytes, cur_index = 0;
47 char propname[NAME_MAX], addrname[NAME_MAX], sizename[NAME_MAX];
49 if (!dn || !addr || !size)
55 snprintf(propname, sizeof(propname), "%sdma-window", prefix);
56 snprintf(addrname, sizeof(addrname), "%s#dma-address-cells", prefix);
57 snprintf(sizename, sizeof(sizename), "%s#dma-size-cells", prefix);
59 dma_window = of_get_property(dn, propname, &bytes);
62 end = dma_window + bytes / sizeof(*dma_window);
64 while (dma_window < end) {
68 /* busno is one cell if supported */
70 *busno = be32_to_cpup(dma_window++);
72 prop = of_get_property(dn, addrname, NULL);
74 prop = of_get_property(dn, "#address-cells", NULL);
76 cells = prop ? be32_to_cpup(prop) : of_n_addr_cells(dn);
79 *addr = of_read_number(dma_window, cells);
82 prop = of_get_property(dn, sizename, NULL);
83 cells = prop ? be32_to_cpup(prop) : of_n_size_cells(dn);
86 *size = of_read_number(dma_window, cells);
89 if (cur_index++ == index)
94 EXPORT_SYMBOL_GPL(of_get_dma_window);
96 void __init of_iommu_init(void)
98 struct device_node *np;
99 const struct of_device_id *match, *matches = &__iommu_of_table;
101 for_each_matching_node_and_match(np, matches, &match) {
102 const of_iommu_init_fn init_fn = match->data;
105 pr_err("Failed to initialise IOMMU %s\n",
106 of_node_full_name(np));