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