system76-edk2/MdeModulePkg/Bus/Pci/PciBusDxe/PciPowerManagement.c
davidhuang 9060e3ec6d 1. Impl PI 1.2 PCI part. Major changes include:
a. Update PciBusDxe module, and move it from IntelFrameworkModulePkg to MdeModulePkg
  b. Move IncompatiblePciDeviceSupportDxe module from IntelFrameworkModulePkg to MdeModulePkg
  c. Update the related consumes in inf/dsc/fdf

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9347 6f19259b-4bc3-4df7-8a09-765794883524
2009-10-20 03:43:40 +00:00

69 lines
1.8 KiB
C

/** @file
Power management support fucntions implementation for PCI Bus module.
Copyright (c) 2006 - 2009, Intel Corporation
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include "PciBus.h"
/**
This function is intended to turn off PWE assertion and
put the device to D0 state if the device supports
PCI Power Management.
@param PciIoDevice PCI device instance.
@retval EFI_UNSUPPORTED PCI Device does not support power management.
@retval EFI_SUCCESS Turned off PWE successfully.
**/
EFI_STATUS
ResetPowerManagementFeature (
IN PCI_IO_DEVICE *PciIoDevice
)
{
EFI_STATUS Status;
UINT8 PowerManagementRegBlock;
UINT16 PowerManagementCSR;
PowerManagementRegBlock = 0;
Status = LocateCapabilityRegBlock (
PciIoDevice,
EFI_PCI_CAPABILITY_ID_PMI,
&PowerManagementRegBlock,
NULL
);
if (EFI_ERROR (Status)) {
return EFI_UNSUPPORTED;
}
//
// Turn off the PWE assertion and put the device into D0 State
//
PowerManagementCSR = 0x8000;
//
// Write PMCSR
//
PciIoDevice->PciIo.Pci.Write (
&PciIoDevice->PciIo,
EfiPciIoWidthUint16,
PowerManagementRegBlock + 4,
1,
&PowerManagementCSR
);
return EFI_SUCCESS;
}