blob: 5dfdfdac92e1bc83862707aab71d356d47a36eff [file] [log] [blame]
Keshavamurthy, Anil S10e52472007-10-21 16:41:41 -07001/*
2 * Copyright (c) 2006, Intel Corporation.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15 * Place - Suite 330, Boston, MA 02111-1307 USA.
16 *
17 * Copyright (C) Ashok Raj <ashok.raj@intel.com>
18 * Copyright (C) Shaohua Li <shaohua.li@intel.com>
19 * Copyright (C) Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
20 *
21 * This file implements early detection/parsing of DMA Remapping Devices
22 * reported to OS through BIOS via DMA remapping reporting (DMAR) ACPI
23 * tables.
24 */
25
26#include <linux/pci.h>
27#include <linux/dmar.h>
28
29#undef PREFIX
30#define PREFIX "DMAR:"
31
32/* No locks are needed as DMA remapping hardware unit
33 * list is constructed at boot time and hotplug of
34 * these units are not supported by the architecture.
35 */
36LIST_HEAD(dmar_drhd_units);
37LIST_HEAD(dmar_rmrr_units);
38
39static struct acpi_table_header * __initdata dmar_tbl;
40
41static void __init dmar_register_drhd_unit(struct dmar_drhd_unit *drhd)
42{
43 /*
44 * add INCLUDE_ALL at the tail, so scan the list will find it at
45 * the very end.
46 */
47 if (drhd->include_all)
48 list_add_tail(&drhd->list, &dmar_drhd_units);
49 else
50 list_add(&drhd->list, &dmar_drhd_units);
51}
52
53static void __init dmar_register_rmrr_unit(struct dmar_rmrr_unit *rmrr)
54{
55 list_add(&rmrr->list, &dmar_rmrr_units);
56}
57
58static int __init dmar_parse_one_dev_scope(struct acpi_dmar_device_scope *scope,
59 struct pci_dev **dev, u16 segment)
60{
61 struct pci_bus *bus;
62 struct pci_dev *pdev = NULL;
63 struct acpi_dmar_pci_path *path;
64 int count;
65
66 bus = pci_find_bus(segment, scope->bus);
67 path = (struct acpi_dmar_pci_path *)(scope + 1);
68 count = (scope->length - sizeof(struct acpi_dmar_device_scope))
69 / sizeof(struct acpi_dmar_pci_path);
70
71 while (count) {
72 if (pdev)
73 pci_dev_put(pdev);
74 /*
75 * Some BIOSes list non-exist devices in DMAR table, just
76 * ignore it
77 */
78 if (!bus) {
79 printk(KERN_WARNING
80 PREFIX "Device scope bus [%d] not found\n",
81 scope->bus);
82 break;
83 }
84 pdev = pci_get_slot(bus, PCI_DEVFN(path->dev, path->fn));
85 if (!pdev) {
86 printk(KERN_WARNING PREFIX
87 "Device scope device [%04x:%02x:%02x.%02x] not found\n",
88 segment, bus->number, path->dev, path->fn);
89 break;
90 }
91 path ++;
92 count --;
93 bus = pdev->subordinate;
94 }
95 if (!pdev) {
96 printk(KERN_WARNING PREFIX
97 "Device scope device [%04x:%02x:%02x.%02x] not found\n",
98 segment, scope->bus, path->dev, path->fn);
99 *dev = NULL;
100 return 0;
101 }
102 if ((scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT && \
103 pdev->subordinate) || (scope->entry_type == \
104 ACPI_DMAR_SCOPE_TYPE_BRIDGE && !pdev->subordinate)) {
105 pci_dev_put(pdev);
106 printk(KERN_WARNING PREFIX
107 "Device scope type does not match for %s\n",
108 pci_name(pdev));
109 return -EINVAL;
110 }
111 *dev = pdev;
112 return 0;
113}
114
115static int __init dmar_parse_dev_scope(void *start, void *end, int *cnt,
116 struct pci_dev ***devices, u16 segment)
117{
118 struct acpi_dmar_device_scope *scope;
119 void * tmp = start;
120 int index;
121 int ret;
122
123 *cnt = 0;
124 while (start < end) {
125 scope = start;
126 if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT ||
127 scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE)
128 (*cnt)++;
129 else
130 printk(KERN_WARNING PREFIX
131 "Unsupported device scope\n");
132 start += scope->length;
133 }
134 if (*cnt == 0)
135 return 0;
136
137 *devices = kcalloc(*cnt, sizeof(struct pci_dev *), GFP_KERNEL);
138 if (!*devices)
139 return -ENOMEM;
140
141 start = tmp;
142 index = 0;
143 while (start < end) {
144 scope = start;
145 if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT ||
146 scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE) {
147 ret = dmar_parse_one_dev_scope(scope,
148 &(*devices)[index], segment);
149 if (ret) {
150 kfree(*devices);
151 return ret;
152 }
153 index ++;
154 }
155 start += scope->length;
156 }
157
158 return 0;
159}
160
161/**
162 * dmar_parse_one_drhd - parses exactly one DMA remapping hardware definition
163 * structure which uniquely represent one DMA remapping hardware unit
164 * present in the platform
165 */
166static int __init
167dmar_parse_one_drhd(struct acpi_dmar_header *header)
168{
169 struct acpi_dmar_hardware_unit *drhd;
170 struct dmar_drhd_unit *dmaru;
171 int ret = 0;
172 static int include_all;
173
174 dmaru = kzalloc(sizeof(*dmaru), GFP_KERNEL);
175 if (!dmaru)
176 return -ENOMEM;
177
178 drhd = (struct acpi_dmar_hardware_unit *)header;
179 dmaru->reg_base_addr = drhd->address;
180 dmaru->include_all = drhd->flags & 0x1; /* BIT0: INCLUDE_ALL */
181
182 if (!dmaru->include_all)
183 ret = dmar_parse_dev_scope((void *)(drhd + 1),
184 ((void *)drhd) + header->length,
185 &dmaru->devices_cnt, &dmaru->devices,
186 drhd->segment);
187 else {
188 /* Only allow one INCLUDE_ALL */
189 if (include_all) {
190 printk(KERN_WARNING PREFIX "Only one INCLUDE_ALL "
191 "device scope is allowed\n");
192 ret = -EINVAL;
193 }
194 include_all = 1;
195 }
196
197 if (ret || (dmaru->devices_cnt == 0 && !dmaru->include_all))
198 kfree(dmaru);
199 else
200 dmar_register_drhd_unit(dmaru);
201 return ret;
202}
203
204static int __init
205dmar_parse_one_rmrr(struct acpi_dmar_header *header)
206{
207 struct acpi_dmar_reserved_memory *rmrr;
208 struct dmar_rmrr_unit *rmrru;
209 int ret = 0;
210
211 rmrru = kzalloc(sizeof(*rmrru), GFP_KERNEL);
212 if (!rmrru)
213 return -ENOMEM;
214
215 rmrr = (struct acpi_dmar_reserved_memory *)header;
216 rmrru->base_address = rmrr->base_address;
217 rmrru->end_address = rmrr->end_address;
218 ret = dmar_parse_dev_scope((void *)(rmrr + 1),
219 ((void *)rmrr) + header->length,
220 &rmrru->devices_cnt, &rmrru->devices, rmrr->segment);
221
222 if (ret || (rmrru->devices_cnt == 0))
223 kfree(rmrru);
224 else
225 dmar_register_rmrr_unit(rmrru);
226 return ret;
227}
228
229static void __init
230dmar_table_print_dmar_entry(struct acpi_dmar_header *header)
231{
232 struct acpi_dmar_hardware_unit *drhd;
233 struct acpi_dmar_reserved_memory *rmrr;
234
235 switch (header->type) {
236 case ACPI_DMAR_TYPE_HARDWARE_UNIT:
237 drhd = (struct acpi_dmar_hardware_unit *)header;
238 printk (KERN_INFO PREFIX
239 "DRHD (flags: 0x%08x)base: 0x%016Lx\n",
240 drhd->flags, drhd->address);
241 break;
242 case ACPI_DMAR_TYPE_RESERVED_MEMORY:
243 rmrr = (struct acpi_dmar_reserved_memory *)header;
244
245 printk (KERN_INFO PREFIX
246 "RMRR base: 0x%016Lx end: 0x%016Lx\n",
247 rmrr->base_address, rmrr->end_address);
248 break;
249 }
250}
251
252/**
253 * parse_dmar_table - parses the DMA reporting table
254 */
255static int __init
256parse_dmar_table(void)
257{
258 struct acpi_table_dmar *dmar;
259 struct acpi_dmar_header *entry_header;
260 int ret = 0;
261
262 dmar = (struct acpi_table_dmar *)dmar_tbl;
263 if (!dmar)
264 return -ENODEV;
265
266 if (!dmar->width) {
267 printk (KERN_WARNING PREFIX "Zero: Invalid DMAR haw\n");
268 return -EINVAL;
269 }
270
271 printk (KERN_INFO PREFIX "Host address width %d\n",
272 dmar->width + 1);
273
274 entry_header = (struct acpi_dmar_header *)(dmar + 1);
275 while (((unsigned long)entry_header) <
276 (((unsigned long)dmar) + dmar_tbl->length)) {
277 dmar_table_print_dmar_entry(entry_header);
278
279 switch (entry_header->type) {
280 case ACPI_DMAR_TYPE_HARDWARE_UNIT:
281 ret = dmar_parse_one_drhd(entry_header);
282 break;
283 case ACPI_DMAR_TYPE_RESERVED_MEMORY:
284 ret = dmar_parse_one_rmrr(entry_header);
285 break;
286 default:
287 printk(KERN_WARNING PREFIX
288 "Unknown DMAR structure type\n");
289 ret = 0; /* for forward compatibility */
290 break;
291 }
292 if (ret)
293 break;
294
295 entry_header = ((void *)entry_header + entry_header->length);
296 }
297 return ret;
298}
299
300
301int __init dmar_table_init(void)
302{
303
304 parse_dmar_table();
305 if (list_empty(&dmar_drhd_units)) {
306 printk(KERN_INFO PREFIX "No DMAR devices found\n");
307 return -ENODEV;
308 }
309 return 0;
310}
311
312/**
313 * early_dmar_detect - checks to see if the platform supports DMAR devices
314 */
315int __init early_dmar_detect(void)
316{
317 acpi_status status = AE_OK;
318
319 /* if we could find DMAR table, then there are DMAR devices */
320 status = acpi_get_table(ACPI_SIG_DMAR, 0,
321 (struct acpi_table_header **)&dmar_tbl);
322
323 if (ACPI_SUCCESS(status) && !dmar_tbl) {
324 printk (KERN_WARNING PREFIX "Unable to map DMAR\n");
325 status = AE_NOT_FOUND;
326 }
327
328 return (ACPI_SUCCESS(status) ? 1 : 0);
329}