--- /dev/null
+/*******************************************************************************
+ *
+ * Module Name: hwpci - Obtain PCI bus, device, and function numbers
+ *
+ ******************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2010, 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);
+}
projects / platform / kernel / linux-rpi.git / commitdiff