| /*++ | |
| Copyright (c) 2005 - 2012, Intel Corporation. All rights reserved.<BR> | |
| 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. | |
| Module Name: | |
| PciPowerManagement.c | |
| Abstract: | |
| PCI Bus Driver | |
| Revision History | |
| --*/ | |
| #include "PciBus.h" | |
| EFI_STATUS | |
| EFIAPI | |
| ResetPowerManagementFeature ( | |
| IN PCI_IO_DEVICE *PciIoDevice | |
| ) | |
| /*++ | |
| Routine Description: | |
| This function is intended to turn off PWE assertion and | |
| put the device to D0 state if the device supports | |
| PCI Power Management. | |
| Arguments: | |
| Returns: | |
| None | |
| --*/ | |
| { | |
| 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 | |
| // | |
| // | |
| // Read PMCSR | |
| // | |
| Status = PciIoDevice->PciIo.Pci.Read ( | |
| &PciIoDevice->PciIo, | |
| EfiPciIoWidthUint16, | |
| PowerManagementRegBlock + 4, | |
| 1, | |
| &PowerManagementCSR | |
| ); | |
| if (!EFI_ERROR (Status)) { | |
| // | |
| // Clear PME_Status bit | |
| // | |
| PowerManagementCSR |= BIT15; | |
| // | |
| // Clear PME_En bit. PowerState = D0. | |
| // | |
| PowerManagementCSR &= ~(BIT8 | BIT1 | BIT0); | |
| // | |
| // Write PMCSR | |
| // | |
| Status = PciIoDevice->PciIo.Pci.Write ( | |
| &PciIoDevice->PciIo, | |
| EfiPciIoWidthUint16, | |
| PowerManagementRegBlock + 4, | |
| 1, | |
| &PowerManagementCSR | |
| ); | |
| } | |
| return Status; | |
| } |