Keshavamurthy, Anil S | 10e5247 | 2007-10-21 16:41:41 -0700 | [diff] [blame] | 1 | /* |
| 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 | */ |
| 36 | LIST_HEAD(dmar_drhd_units); |
| 37 | LIST_HEAD(dmar_rmrr_units); |
| 38 | |
| 39 | static struct acpi_table_header * __initdata dmar_tbl; |
| 40 | |
| 41 | static 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 | |
| 53 | static void __init dmar_register_rmrr_unit(struct dmar_rmrr_unit *rmrr) |
| 54 | { |
| 55 | list_add(&rmrr->list, &dmar_rmrr_units); |
| 56 | } |
| 57 | |
| 58 | static 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 | |
| 115 | static 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 | */ |
| 166 | static int __init |
| 167 | dmar_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 | |
| 204 | static int __init |
| 205 | dmar_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 | |
| 229 | static void __init |
| 230 | dmar_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 | */ |
| 255 | static int __init |
| 256 | parse_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 | |
| 301 | int __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 | */ |
| 315 | int __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 | } |