/******************************************************************************* * * Module Name: hwpci - Obtain PCI bus, device, and function numbers * ******************************************************************************/ /* * Copyright (C) 2000 - 2012, Intel Corp. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions, and the following disclaimer, * without modification. * 2. Redistributions in binary form must reproduce at minimum a disclaimer * substantially similar to the "NO WARRANTY" disclaimer below * ("Disclaimer") and any redistribution must be conditioned upon * including a substantially similar Disclaimer requirement for further * binary redistribution. * 3. Neither the names of the above-listed copyright holders nor the names * of any contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * NO WARRANTY * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGES. */ #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 = NULL; 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); } /* Always 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; struct acpi_pci_device *list_head = NULL; /* * 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. */ current_device = pci_region; while (1) { status = acpi_get_parent(current_device, &parent_device); if (ACPI_FAILURE(status)) { return (status); } /* Finished when we reach the PCI root device (PNP0A03 or PNP0A08) */ if (parent_device == root_pci_device) { *return_list_head = list_head; return (AE_OK); } list_element = ACPI_ALLOCATE(sizeof(struct acpi_pci_device)); if (!list_element) { return (AE_NO_MEMORY); } /* Put new element at the head of the list */ list_element->next = list_head; list_element->device = parent_device; 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_ACPI_STATUS(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_ACPI_STATUS(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); }