OvmfPkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / OvmfPkg / Library / AcpiTimerLib / BaseAcpiTimerLib.c

/** @file\r
  Provide constructor and GetTick for Base instance of ACPI Timer Library\r
\r
  Copyright (C) 2014, Gabriel L. Somlo <somlo@cmu.edu>\r
\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
**/\r
\r
#include <Library/DebugLib.h>\r
#include <Library/IoLib.h>\r
#include <Library/PciLib.h>\r
#include <OvmfPlatforms.h>\r
\r
//\r
// Cached ACPI Timer IO Address\r
//\r
STATIC UINT32 mAcpiTimerIoAddr;\r
\r
/**\r
  The constructor function caches the ACPI tick counter address, and,\r
  if necessary, enables ACPI IO space.\r
\r
  @retval EFI_SUCCESS   The constructor always returns RETURN_SUCCESS.\r
\r
**/\r
RETURN_STATUS\r
EFIAPI\r
AcpiTimerLibConstructor (\r
  VOID\r
  )\r
{\r
  UINT16 HostBridgeDevId;\r
  UINTN Pmba;\r
  UINT32 PmbaAndVal;\r
  UINT32 PmbaOrVal;\r
  UINTN AcpiCtlReg;\r
  UINT8 AcpiEnBit;\r
\r
  //\r
  // Query Host Bridge DID to determine platform type\r
  //\r
  HostBridgeDevId = PciRead16 (OVMF_HOSTBRIDGE_DID);\r
  switch (HostBridgeDevId) {\r
    case INTEL_82441_DEVICE_ID:\r
      Pmba       = POWER_MGMT_REGISTER_PIIX4 (PIIX4_PMBA);\r
      PmbaAndVal = ~(UINT32)PIIX4_PMBA_MASK;\r
      PmbaOrVal  = PIIX4_PMBA_VALUE;\r
      AcpiCtlReg = POWER_MGMT_REGISTER_PIIX4 (PIIX4_PMREGMISC);\r
      AcpiEnBit  = PIIX4_PMREGMISC_PMIOSE;\r
      break;\r
    case INTEL_Q35_MCH_DEVICE_ID:\r
      Pmba       = POWER_MGMT_REGISTER_Q35 (ICH9_PMBASE);\r
      PmbaAndVal = ~(UINT32)ICH9_PMBASE_MASK;\r
      PmbaOrVal  = ICH9_PMBASE_VALUE;\r
      AcpiCtlReg = POWER_MGMT_REGISTER_Q35 (ICH9_ACPI_CNTL);\r
      AcpiEnBit  = ICH9_ACPI_CNTL_ACPI_EN;\r
      break;\r
    default:\r
      DEBUG ((EFI_D_ERROR, "%a: Unknown Host Bridge Device ID: 0x%04x\n",\r
        __FUNCTION__, HostBridgeDevId));\r
      ASSERT (FALSE);\r
      return RETURN_UNSUPPORTED;\r
  }\r
\r
  //\r
  // Check to see if the Power Management Base Address is already enabled\r
  //\r
  if ((PciRead8 (AcpiCtlReg) & AcpiEnBit) == 0) {\r
    //\r
    // If the Power Management Base Address is not programmed,\r
    // then program it now.\r
    //\r
    PciAndThenOr32 (Pmba, PmbaAndVal, PmbaOrVal);\r
\r
    //\r
    // Enable PMBA I/O port decodes\r
    //\r
    PciOr8 (AcpiCtlReg, AcpiEnBit);\r
  }\r
\r
  mAcpiTimerIoAddr = (PciRead32 (Pmba) & ~PMBA_RTE) + ACPI_TIMER_OFFSET;\r
  return RETURN_SUCCESS;\r
}\r
\r
/**\r
  Internal function to read the current tick counter of ACPI.\r
\r
  Read the current ACPI tick counter using the counter address cached\r
  by this instance's constructor.\r
\r
  @return The tick counter read.\r
\r
**/\r
UINT32\r
InternalAcpiGetTimerTick (\r
  VOID\r
  )\r
{\r
  //\r
  //   Return the current ACPI timer value.\r
  //\r
  return IoRead32 (mAcpiTimerIoAddr);\r
}\r