Erik Schmauss | 9585763 | 2018-03-14 16:13:07 -0700 | [diff] [blame] | 1 | // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 2 | /******************************************************************************* |
| 3 | * |
| 4 | * Module Name: hwpci - Obtain PCI bus, device, and function numbers |
| 5 | * |
| 6 | ******************************************************************************/ |
| 7 | |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 8 | #include <acpi/acpi.h> |
| 9 | #include "accommon.h" |
| 10 | |
| 11 | #define _COMPONENT ACPI_NAMESPACE |
| 12 | ACPI_MODULE_NAME("hwpci") |
| 13 | |
| 14 | /* PCI configuration space values */ |
| 15 | #define PCI_CFG_HEADER_TYPE_REG 0x0E |
| 16 | #define PCI_CFG_PRIMARY_BUS_NUMBER_REG 0x18 |
| 17 | #define PCI_CFG_SECONDARY_BUS_NUMBER_REG 0x19 |
| 18 | /* PCI header values */ |
| 19 | #define PCI_HEADER_TYPE_MASK 0x7F |
| 20 | #define PCI_TYPE_BRIDGE 0x01 |
| 21 | #define PCI_TYPE_CARDBUS_BRIDGE 0x02 |
| 22 | typedef struct acpi_pci_device { |
| 23 | acpi_handle device; |
| 24 | struct acpi_pci_device *next; |
| 25 | |
| 26 | } acpi_pci_device; |
| 27 | |
| 28 | /* Local prototypes */ |
| 29 | |
| 30 | static acpi_status |
| 31 | acpi_hw_build_pci_list(acpi_handle root_pci_device, |
| 32 | acpi_handle pci_region, |
| 33 | struct acpi_pci_device **return_list_head); |
| 34 | |
| 35 | static acpi_status |
| 36 | acpi_hw_process_pci_list(struct acpi_pci_id *pci_id, |
| 37 | struct acpi_pci_device *list_head); |
| 38 | |
| 39 | static void acpi_hw_delete_pci_list(struct acpi_pci_device *list_head); |
| 40 | |
| 41 | static acpi_status |
| 42 | acpi_hw_get_pci_device_info(struct acpi_pci_id *pci_id, |
| 43 | acpi_handle pci_device, |
| 44 | u16 *bus_number, u8 *is_bridge); |
| 45 | |
| 46 | /******************************************************************************* |
| 47 | * |
| 48 | * FUNCTION: acpi_hw_derive_pci_id |
| 49 | * |
| 50 | * PARAMETERS: pci_id - Initial values for the PCI ID. May be |
| 51 | * modified by this function. |
| 52 | * root_pci_device - A handle to a PCI device object. This |
| 53 | * object must be a PCI Root Bridge having a |
| 54 | * _HID value of either PNP0A03 or PNP0A08 |
| 55 | * pci_region - A handle to a PCI configuration space |
| 56 | * Operation Region being initialized |
| 57 | * |
| 58 | * RETURN: Status |
| 59 | * |
| 60 | * DESCRIPTION: This function derives a full PCI ID for a PCI device, |
| 61 | * consisting of a Segment number, Bus number, Device number, |
| 62 | * and function code. |
| 63 | * |
| 64 | * The PCI hardware dynamically configures PCI bus numbers |
| 65 | * depending on the bus topology discovered during system |
| 66 | * initialization. This function is invoked during configuration |
| 67 | * of a PCI_Config Operation Region in order to (possibly) update |
| 68 | * the Bus/Device/Function numbers in the pci_id with the actual |
| 69 | * values as determined by the hardware and operating system |
| 70 | * configuration. |
| 71 | * |
| 72 | * The pci_id parameter is initially populated during the Operation |
| 73 | * Region initialization. This function is then called, and is |
| 74 | * will make any necessary modifications to the Bus, Device, or |
| 75 | * Function number PCI ID subfields as appropriate for the |
| 76 | * current hardware and OS configuration. |
| 77 | * |
| 78 | * NOTE: Created 08/2010. Replaces the previous OSL acpi_os_derive_pci_id |
| 79 | * interface since this feature is OS-independent. This module |
| 80 | * specifically avoids any use of recursion by building a local |
| 81 | * temporary device list. |
| 82 | * |
| 83 | ******************************************************************************/ |
| 84 | |
| 85 | acpi_status |
| 86 | acpi_hw_derive_pci_id(struct acpi_pci_id *pci_id, |
| 87 | acpi_handle root_pci_device, acpi_handle pci_region) |
| 88 | { |
| 89 | acpi_status status; |
Lv Zheng | 2900d56 | 2015-05-21 10:31:12 +0800 | [diff] [blame] | 90 | struct acpi_pci_device *list_head; |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 91 | |
| 92 | ACPI_FUNCTION_TRACE(hw_derive_pci_id); |
| 93 | |
| 94 | if (!pci_id) { |
| 95 | return_ACPI_STATUS(AE_BAD_PARAMETER); |
| 96 | } |
| 97 | |
| 98 | /* Build a list of PCI devices, from pci_region up to root_pci_device */ |
| 99 | |
| 100 | status = |
| 101 | acpi_hw_build_pci_list(root_pci_device, pci_region, &list_head); |
| 102 | if (ACPI_SUCCESS(status)) { |
| 103 | |
| 104 | /* Walk the list, updating the PCI device/function/bus numbers */ |
| 105 | |
| 106 | status = acpi_hw_process_pci_list(pci_id, list_head); |
David E. Box | c28fa24 | 2014-04-30 10:04:20 +0800 | [diff] [blame] | 107 | |
| 108 | /* Delete the list */ |
| 109 | |
| 110 | acpi_hw_delete_pci_list(list_head); |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 111 | } |
| 112 | |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 113 | return_ACPI_STATUS(status); |
| 114 | } |
| 115 | |
| 116 | /******************************************************************************* |
| 117 | * |
| 118 | * FUNCTION: acpi_hw_build_pci_list |
| 119 | * |
| 120 | * PARAMETERS: root_pci_device - A handle to a PCI device object. This |
| 121 | * object is guaranteed to be a PCI Root |
| 122 | * Bridge having a _HID value of either |
| 123 | * PNP0A03 or PNP0A08 |
| 124 | * pci_region - A handle to the PCI configuration space |
| 125 | * Operation Region |
| 126 | * return_list_head - Where the PCI device list is returned |
| 127 | * |
| 128 | * RETURN: Status |
| 129 | * |
| 130 | * DESCRIPTION: Builds a list of devices from the input PCI region up to the |
| 131 | * Root PCI device for this namespace subtree. |
| 132 | * |
| 133 | ******************************************************************************/ |
| 134 | |
| 135 | static acpi_status |
| 136 | acpi_hw_build_pci_list(acpi_handle root_pci_device, |
| 137 | acpi_handle pci_region, |
| 138 | struct acpi_pci_device **return_list_head) |
| 139 | { |
| 140 | acpi_handle current_device; |
| 141 | acpi_handle parent_device; |
| 142 | acpi_status status; |
| 143 | struct acpi_pci_device *list_element; |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 144 | |
| 145 | /* |
| 146 | * Ascend namespace branch until the root_pci_device is reached, building |
| 147 | * a list of device nodes. Loop will exit when either the PCI device is |
| 148 | * found, or the root of the namespace is reached. |
| 149 | */ |
Lv Zheng | 2900d56 | 2015-05-21 10:31:12 +0800 | [diff] [blame] | 150 | *return_list_head = NULL; |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 151 | current_device = pci_region; |
| 152 | while (1) { |
| 153 | status = acpi_get_parent(current_device, &parent_device); |
| 154 | if (ACPI_FAILURE(status)) { |
David E. Box | c28fa24 | 2014-04-30 10:04:20 +0800 | [diff] [blame] | 155 | |
| 156 | /* Must delete the list before exit */ |
| 157 | |
| 158 | acpi_hw_delete_pci_list(*return_list_head); |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 159 | return (status); |
| 160 | } |
| 161 | |
| 162 | /* Finished when we reach the PCI root device (PNP0A03 or PNP0A08) */ |
| 163 | |
| 164 | if (parent_device == root_pci_device) { |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 165 | return (AE_OK); |
| 166 | } |
| 167 | |
| 168 | list_element = ACPI_ALLOCATE(sizeof(struct acpi_pci_device)); |
| 169 | if (!list_element) { |
David E. Box | c28fa24 | 2014-04-30 10:04:20 +0800 | [diff] [blame] | 170 | |
| 171 | /* Must delete the list before exit */ |
| 172 | |
| 173 | acpi_hw_delete_pci_list(*return_list_head); |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 174 | return (AE_NO_MEMORY); |
| 175 | } |
| 176 | |
| 177 | /* Put new element at the head of the list */ |
| 178 | |
Lv Zheng | 2900d56 | 2015-05-21 10:31:12 +0800 | [diff] [blame] | 179 | list_element->next = *return_list_head; |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 180 | list_element->device = parent_device; |
Lv Zheng | 2900d56 | 2015-05-21 10:31:12 +0800 | [diff] [blame] | 181 | *return_list_head = list_element; |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 182 | |
| 183 | current_device = parent_device; |
| 184 | } |
| 185 | } |
| 186 | |
| 187 | /******************************************************************************* |
| 188 | * |
| 189 | * FUNCTION: acpi_hw_process_pci_list |
| 190 | * |
| 191 | * PARAMETERS: pci_id - Initial values for the PCI ID. May be |
| 192 | * modified by this function. |
| 193 | * list_head - Device list created by |
| 194 | * acpi_hw_build_pci_list |
| 195 | * |
| 196 | * RETURN: Status |
| 197 | * |
| 198 | * DESCRIPTION: Walk downward through the PCI device list, getting the device |
| 199 | * info for each, via the PCI configuration space and updating |
| 200 | * the PCI ID as necessary. Deletes the list during traversal. |
| 201 | * |
| 202 | ******************************************************************************/ |
| 203 | |
| 204 | static acpi_status |
| 205 | acpi_hw_process_pci_list(struct acpi_pci_id *pci_id, |
| 206 | struct acpi_pci_device *list_head) |
| 207 | { |
| 208 | acpi_status status = AE_OK; |
| 209 | struct acpi_pci_device *info; |
| 210 | u16 bus_number; |
| 211 | u8 is_bridge = TRUE; |
| 212 | |
| 213 | ACPI_FUNCTION_NAME(hw_process_pci_list); |
| 214 | |
| 215 | ACPI_DEBUG_PRINT((ACPI_DB_OPREGION, |
| 216 | "Input PciId: Seg %4.4X Bus %4.4X Dev %4.4X Func %4.4X\n", |
| 217 | pci_id->segment, pci_id->bus, pci_id->device, |
| 218 | pci_id->function)); |
| 219 | |
| 220 | bus_number = pci_id->bus; |
| 221 | |
| 222 | /* |
| 223 | * Descend down the namespace tree, collecting PCI device, function, |
| 224 | * and bus numbers. bus_number is only important for PCI bridges. |
| 225 | * Algorithm: As we descend the tree, use the last valid PCI device, |
| 226 | * function, and bus numbers that are discovered, and assign them |
| 227 | * to the PCI ID for the target device. |
| 228 | */ |
| 229 | info = list_head; |
| 230 | while (info) { |
| 231 | status = acpi_hw_get_pci_device_info(pci_id, info->device, |
| 232 | &bus_number, &is_bridge); |
| 233 | if (ACPI_FAILURE(status)) { |
Bob Moore | 68aafc3 | 2012-10-31 02:26:01 +0000 | [diff] [blame] | 234 | return (status); |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 235 | } |
| 236 | |
| 237 | info = info->next; |
| 238 | } |
| 239 | |
| 240 | ACPI_DEBUG_PRINT((ACPI_DB_OPREGION, |
| 241 | "Output PciId: Seg %4.4X Bus %4.4X Dev %4.4X Func %4.4X " |
| 242 | "Status %X BusNumber %X IsBridge %X\n", |
| 243 | pci_id->segment, pci_id->bus, pci_id->device, |
| 244 | pci_id->function, status, bus_number, is_bridge)); |
| 245 | |
Bob Moore | 68aafc3 | 2012-10-31 02:26:01 +0000 | [diff] [blame] | 246 | return (AE_OK); |
Bob Moore | 95abccb | 2010-09-15 13:22:46 +0800 | [diff] [blame] | 247 | } |
| 248 | |
| 249 | /******************************************************************************* |
| 250 | * |
| 251 | * FUNCTION: acpi_hw_delete_pci_list |
| 252 | * |
| 253 | * PARAMETERS: list_head - Device list created by |
| 254 | * acpi_hw_build_pci_list |
| 255 | * |
| 256 | * RETURN: None |
| 257 | * |
| 258 | * DESCRIPTION: Free the entire PCI list. |
| 259 | * |
| 260 | ******************************************************************************/ |
| 261 | |
| 262 | static void acpi_hw_delete_pci_list(struct acpi_pci_device *list_head) |
| 263 | { |
| 264 | struct acpi_pci_device *next; |
| 265 | struct acpi_pci_device *previous; |
| 266 | |
| 267 | next = list_head; |
| 268 | while (next) { |
| 269 | previous = next; |
| 270 | next = previous->next; |
| 271 | ACPI_FREE(previous); |
| 272 | } |
| 273 | } |
| 274 | |
| 275 | /******************************************************************************* |
| 276 | * |
| 277 | * FUNCTION: acpi_hw_get_pci_device_info |
| 278 | * |
| 279 | * PARAMETERS: pci_id - Initial values for the PCI ID. May be |
| 280 | * modified by this function. |
| 281 | * pci_device - Handle for the PCI device object |
| 282 | * bus_number - Where a PCI bridge bus number is returned |
| 283 | * is_bridge - Return value, indicates if this PCI |
| 284 | * device is a PCI bridge |
| 285 | * |
| 286 | * RETURN: Status |
| 287 | * |
| 288 | * DESCRIPTION: Get the device info for a single PCI device object. Get the |
| 289 | * _ADR (contains PCI device and function numbers), and for PCI |
| 290 | * bridge devices, get the bus number from PCI configuration |
| 291 | * space. |
| 292 | * |
| 293 | ******************************************************************************/ |
| 294 | |
| 295 | static acpi_status |
| 296 | acpi_hw_get_pci_device_info(struct acpi_pci_id *pci_id, |
| 297 | acpi_handle pci_device, |
| 298 | u16 *bus_number, u8 *is_bridge) |
| 299 | { |
| 300 | acpi_status status; |
| 301 | acpi_object_type object_type; |
| 302 | u64 return_value; |
| 303 | u64 pci_value; |
| 304 | |
| 305 | /* We only care about objects of type Device */ |
| 306 | |
| 307 | status = acpi_get_type(pci_device, &object_type); |
| 308 | if (ACPI_FAILURE(status)) { |
| 309 | return (status); |
| 310 | } |
| 311 | |
| 312 | if (object_type != ACPI_TYPE_DEVICE) { |
| 313 | return (AE_OK); |
| 314 | } |
| 315 | |
| 316 | /* We need an _ADR. Ignore device if not present */ |
| 317 | |
| 318 | status = acpi_ut_evaluate_numeric_object(METHOD_NAME__ADR, |
| 319 | pci_device, &return_value); |
| 320 | if (ACPI_FAILURE(status)) { |
| 321 | return (AE_OK); |
| 322 | } |
| 323 | |
| 324 | /* |
| 325 | * From _ADR, get the PCI Device and Function and |
| 326 | * update the PCI ID. |
| 327 | */ |
| 328 | pci_id->device = ACPI_HIWORD(ACPI_LODWORD(return_value)); |
| 329 | pci_id->function = ACPI_LOWORD(ACPI_LODWORD(return_value)); |
| 330 | |
| 331 | /* |
| 332 | * If the previous device was a bridge, use the previous |
| 333 | * device bus number |
| 334 | */ |
| 335 | if (*is_bridge) { |
| 336 | pci_id->bus = *bus_number; |
| 337 | } |
| 338 | |
| 339 | /* |
| 340 | * Get the bus numbers from PCI Config space: |
| 341 | * |
| 342 | * First, get the PCI header_type |
| 343 | */ |
| 344 | *is_bridge = FALSE; |
| 345 | status = acpi_os_read_pci_configuration(pci_id, |
| 346 | PCI_CFG_HEADER_TYPE_REG, |
| 347 | &pci_value, 8); |
| 348 | if (ACPI_FAILURE(status)) { |
| 349 | return (status); |
| 350 | } |
| 351 | |
| 352 | /* We only care about bridges (1=pci_bridge, 2=card_bus_bridge) */ |
| 353 | |
| 354 | pci_value &= PCI_HEADER_TYPE_MASK; |
| 355 | |
| 356 | if ((pci_value != PCI_TYPE_BRIDGE) && |
| 357 | (pci_value != PCI_TYPE_CARDBUS_BRIDGE)) { |
| 358 | return (AE_OK); |
| 359 | } |
| 360 | |
| 361 | /* Bridge: Get the Primary bus_number */ |
| 362 | |
| 363 | status = acpi_os_read_pci_configuration(pci_id, |
| 364 | PCI_CFG_PRIMARY_BUS_NUMBER_REG, |
| 365 | &pci_value, 8); |
| 366 | if (ACPI_FAILURE(status)) { |
| 367 | return (status); |
| 368 | } |
| 369 | |
| 370 | *is_bridge = TRUE; |
| 371 | pci_id->bus = (u16)pci_value; |
| 372 | |
| 373 | /* Bridge: Get the Secondary bus_number */ |
| 374 | |
| 375 | status = acpi_os_read_pci_configuration(pci_id, |
| 376 | PCI_CFG_SECONDARY_BUS_NUMBER_REG, |
| 377 | &pci_value, 8); |
| 378 | if (ACPI_FAILURE(status)) { |
| 379 | return (status); |
| 380 | } |
| 381 | |
| 382 | *bus_number = (u16)pci_value; |
| 383 | return (AE_OK); |
| 384 | } |