/*******************************************************************************
*
* Module Name: hwpci - Obtain PCI bus, device, and function numbers
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2018, 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.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
AcpiHwBuildPciList (
ACPI_HANDLE RootPciDevice,
ACPI_HANDLE PciRegion,
ACPI_PCI_DEVICE **ReturnListHead);
static ACPI_STATUS
AcpiHwProcessPciList (
ACPI_PCI_ID *PciId,
ACPI_PCI_DEVICE *ListHead);
static void
AcpiHwDeletePciList (
ACPI_PCI_DEVICE *ListHead);
static ACPI_STATUS
AcpiHwGetPciDeviceInfo (
ACPI_PCI_ID *PciId,
ACPI_HANDLE PciDevice,
UINT16 *BusNumber,
BOOLEAN *IsBridge);
/*******************************************************************************
*
* FUNCTION: AcpiHwDerivePciId
*
* PARAMETERS: PciId - Initial values for the PCI ID. May be
* modified by this function.
* RootPciDevice - A handle to a PCI device object. This
* object must be a PCI Root Bridge having a
* _HID value of either PNP0A03 or PNP0A08
* PciRegion - 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 PciId with the actual
* values as determined by the hardware and operating system
* configuration.
*
* The PciId 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 AcpiOsDerivePciId
* interface since this feature is OS-independent. This module
* specifically avoids any use of recursion by building a local
* temporary device list.
*
******************************************************************************/
ACPI_STATUS
AcpiHwDerivePciId (
ACPI_PCI_ID *PciId,
ACPI_HANDLE RootPciDevice,
ACPI_HANDLE PciRegion)
{
ACPI_STATUS Status;
ACPI_PCI_DEVICE *ListHead;
ACPI_FUNCTION_TRACE (HwDerivePciId);
if (!PciId)
{
return_ACPI_STATUS (AE_BAD_PARAMETER);
}
/* Build a list of PCI devices, from PciRegion up to RootPciDevice */
Status = AcpiHwBuildPciList (RootPciDevice, PciRegion, &ListHead);
if (ACPI_SUCCESS (Status))
{
/* Walk the list, updating the PCI device/function/bus numbers */
Status = AcpiHwProcessPciList (PciId, ListHead);
/* Delete the list */
AcpiHwDeletePciList (ListHead);
}
return_ACPI_STATUS (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiHwBuildPciList
*
* PARAMETERS: RootPciDevice - 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
* PciRegion - A handle to the PCI configuration space
* Operation Region
* ReturnListHead - 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
AcpiHwBuildPciList (
ACPI_HANDLE RootPciDevice,
ACPI_HANDLE PciRegion,
ACPI_PCI_DEVICE **ReturnListHead)
{
ACPI_HANDLE CurrentDevice;
ACPI_HANDLE ParentDevice;
ACPI_STATUS Status;
ACPI_PCI_DEVICE *ListElement;
/*
* Ascend namespace branch until the RootPciDevice 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.
*/
*ReturnListHead = NULL;
CurrentDevice = PciRegion;
while (1)
{
Status = AcpiGetParent (CurrentDevice, &ParentDevice);
if (ACPI_FAILURE (Status))
{
/* Must delete the list before exit */
AcpiHwDeletePciList (*ReturnListHead);
return (Status);
}
/* Finished when we reach the PCI root device (PNP0A03 or PNP0A08) */
if (ParentDevice == RootPciDevice)
{
return (AE_OK);
}
ListElement = ACPI_ALLOCATE (sizeof (ACPI_PCI_DEVICE));
if (!ListElement)
{
/* Must delete the list before exit */
AcpiHwDeletePciList (*ReturnListHead);
return (AE_NO_MEMORY);
}
/* Put new element at the head of the list */
ListElement->Next = *ReturnListHead;
ListElement->Device = ParentDevice;
*ReturnListHead = ListElement;
CurrentDevice = ParentDevice;
}
}
/*******************************************************************************
*
* FUNCTION: AcpiHwProcessPciList
*
* PARAMETERS: PciId - Initial values for the PCI ID. May be
* modified by this function.
* ListHead - Device list created by
* AcpiHwBuildPciList
*
* 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
AcpiHwProcessPciList (
ACPI_PCI_ID *PciId,
ACPI_PCI_DEVICE *ListHead)
{
ACPI_STATUS Status = AE_OK;
ACPI_PCI_DEVICE *Info;
UINT16 BusNumber;
BOOLEAN IsBridge = TRUE;
ACPI_FUNCTION_NAME (HwProcessPciList);
ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
"Input PciId: Seg %4.4X Bus %4.4X Dev %4.4X Func %4.4X\n",
PciId->Segment, PciId->Bus, PciId->Device, PciId->Function));
BusNumber = PciId->Bus;
/*
* Descend down the namespace tree, collecting PCI device, function,
* and bus numbers. BusNumber 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 = ListHead;
while (Info)
{
Status = AcpiHwGetPciDeviceInfo (PciId, Info->Device,
&BusNumber, &IsBridge);
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",
PciId->Segment, PciId->Bus, PciId->Device, PciId->Function,
Status, BusNumber, IsBridge));
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: AcpiHwDeletePciList
*
* PARAMETERS: ListHead - Device list created by
* AcpiHwBuildPciList
*
* RETURN: None
*
* DESCRIPTION: Free the entire PCI list.
*
******************************************************************************/
static void
AcpiHwDeletePciList (
ACPI_PCI_DEVICE *ListHead)
{
ACPI_PCI_DEVICE *Next;
ACPI_PCI_DEVICE *Previous;
Next = ListHead;
while (Next)
{
Previous = Next;
Next = Previous->Next;
ACPI_FREE (Previous);
}
}
/*******************************************************************************
*
* FUNCTION: AcpiHwGetPciDeviceInfo
*
* PARAMETERS: PciId - Initial values for the PCI ID. May be
* modified by this function.
* PciDevice - Handle for the PCI device object
* BusNumber - Where a PCI bridge bus number is returned
* IsBridge - 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
AcpiHwGetPciDeviceInfo (
ACPI_PCI_ID *PciId,
ACPI_HANDLE PciDevice,
UINT16 *BusNumber,
BOOLEAN *IsBridge)
{
ACPI_STATUS Status;
ACPI_OBJECT_TYPE ObjectType;
UINT64 ReturnValue;
UINT64 PciValue;
/* We only care about objects of type Device */
Status = AcpiGetType (PciDevice, &ObjectType);
if (ACPI_FAILURE (Status))
{
return (Status);
}
if (ObjectType != ACPI_TYPE_DEVICE)
{
return (AE_OK);
}
/* We need an _ADR. Ignore device if not present */
Status = AcpiUtEvaluateNumericObject (METHOD_NAME__ADR,
PciDevice, &ReturnValue);
if (ACPI_FAILURE (Status))
{
return (AE_OK);
}
/*
* From _ADR, get the PCI Device and Function and
* update the PCI ID.
*/
PciId->Device = ACPI_HIWORD (ACPI_LODWORD (ReturnValue));
PciId->Function = ACPI_LOWORD (ACPI_LODWORD (ReturnValue));
/*
* If the previous device was a bridge, use the previous
* device bus number
*/
if (*IsBridge)
{
PciId->Bus = *BusNumber;
}
/*
* Get the bus numbers from PCI Config space:
*
* First, get the PCI HeaderType
*/
*IsBridge = FALSE;
Status = AcpiOsReadPciConfiguration (PciId,
PCI_CFG_HEADER_TYPE_REG, &PciValue, 8);
if (ACPI_FAILURE (Status))
{
return (Status);
}
/* We only care about bridges (1=PciBridge, 2=CardBusBridge) */
PciValue &= PCI_HEADER_TYPE_MASK;
if ((PciValue != PCI_TYPE_BRIDGE) &&
(PciValue != PCI_TYPE_CARDBUS_BRIDGE))
{
return (AE_OK);
}
/* Bridge: Get the Primary BusNumber */
Status = AcpiOsReadPciConfiguration (PciId,
PCI_CFG_PRIMARY_BUS_NUMBER_REG, &PciValue, 8);
if (ACPI_FAILURE (Status))
{
return (Status);
}
*IsBridge = TRUE;
PciId->Bus = (UINT16) PciValue;
/* Bridge: Get the Secondary BusNumber */
Status = AcpiOsReadPciConfiguration (PciId,
PCI_CFG_SECONDARY_BUS_NUMBER_REG, &PciValue, 8);
if (ACPI_FAILURE (Status))
{
return (Status);
}
*BusNumber = (UINT16) PciValue;
return (AE_OK);
}