]>
git.proxmox.com Git - mirror_edk2.git/blob - OvmfPkg/Library/AcpiTimerLib/BaseRomAcpiTimerLib.c
2 Provide constructor and GetTick for BaseRom instance of ACPI Timer Library
4 Copyright (c) 2008 - 2012, Intel Corporation. All rights reserved.
5 Copyright (c) 2011, Andrei Warkentin <andreiw@motorola.com>
7 SPDX-License-Identifier: BSD-2-Clause-Patent
10 #include <Library/DebugLib.h>
11 #include <Library/IoLib.h>
12 #include <Library/PciLib.h>
13 #include <OvmfPlatforms.h>
16 The constructor function enables ACPI IO space.
18 If ACPI I/O space not enabled, this function will enable it.
19 It will always return RETURN_SUCCESS.
21 @retval EFI_SUCCESS The constructor always returns RETURN_SUCCESS.
26 AcpiTimerLibConstructor (
30 UINT16 HostBridgeDevId
;
38 // Query Host Bridge DID to determine platform type
40 HostBridgeDevId
= PciRead16 (OVMF_HOSTBRIDGE_DID
);
41 switch (HostBridgeDevId
) {
42 case INTEL_82441_DEVICE_ID
:
43 Pmba
= POWER_MGMT_REGISTER_PIIX4 (PIIX4_PMBA
);
44 PmbaAndVal
= ~(UINT32
)PIIX4_PMBA_MASK
;
45 PmbaOrVal
= PIIX4_PMBA_VALUE
;
46 AcpiCtlReg
= POWER_MGMT_REGISTER_PIIX4 (PIIX4_PMREGMISC
);
47 AcpiEnBit
= PIIX4_PMREGMISC_PMIOSE
;
49 case INTEL_Q35_MCH_DEVICE_ID
:
50 Pmba
= POWER_MGMT_REGISTER_Q35 (ICH9_PMBASE
);
51 PmbaAndVal
= ~(UINT32
)ICH9_PMBASE_MASK
;
52 PmbaOrVal
= ICH9_PMBASE_VALUE
;
53 AcpiCtlReg
= POWER_MGMT_REGISTER_Q35 (ICH9_ACPI_CNTL
);
54 AcpiEnBit
= ICH9_ACPI_CNTL_ACPI_EN
;
57 DEBUG ((EFI_D_ERROR
, "%a: Unknown Host Bridge Device ID: 0x%04x\n",
58 __FUNCTION__
, HostBridgeDevId
));
60 return RETURN_UNSUPPORTED
;
64 // Check to see if the Power Management Base Address is already enabled
66 if ((PciRead8 (AcpiCtlReg
) & AcpiEnBit
) == 0) {
68 // If the Power Management Base Address is not programmed,
69 // then program it now.
71 PciAndThenOr32 (Pmba
, PmbaAndVal
, PmbaOrVal
);
74 // Enable PMBA I/O port decodes
76 PciOr8 (AcpiCtlReg
, AcpiEnBit
);
79 return RETURN_SUCCESS
;
83 Internal function to read the current tick counter of ACPI.
85 Dynamically compute the address of the ACPI tick counter based on the
86 properties of the underlying platform, to avoid relying on global variables.
88 @return The tick counter read.
92 InternalAcpiGetTimerTick (
96 UINT16 HostBridgeDevId
;
100 // Query Host Bridge DID to determine platform type
102 HostBridgeDevId
= PciRead16 (OVMF_HOSTBRIDGE_DID
);
103 switch (HostBridgeDevId
) {
104 case INTEL_82441_DEVICE_ID
:
105 Pmba
= POWER_MGMT_REGISTER_PIIX4 (PIIX4_PMBA
);
107 case INTEL_Q35_MCH_DEVICE_ID
:
108 Pmba
= POWER_MGMT_REGISTER_Q35 (ICH9_PMBASE
);
111 DEBUG ((EFI_D_ERROR
, "%a: Unknown Host Bridge Device ID: 0x%04x\n",
112 __FUNCTION__
, HostBridgeDevId
));
118 // Read PMBA to read and return the current ACPI timer value.
120 return IoRead32 ((PciRead32 (Pmba
) & ~PMBA_RTE
) + ACPI_TIMER_OFFSET
);