Vlv2TbltDevicePkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / Vlv2TbltDevicePkg / Metronome / LegacyMetronome.c

/** @file\r
\r
  Copyright (c) 2004  - 2014, Intel Corporation. All rights reserved.<BR>\r
                                                                                   \r\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
                                                                                   \r\r
\r
Module Name:\r
\r
\r
  LegacyMetronome.c\r
\r
Abstract:\r
\r
  This contains the installation function for the driver.\r
\r
--*/\r
\r
#include "LegacyMetronome.h"\r
\r
//\r
// Handle for the Metronome Architectural Protocol instance produced by this driver\r
//\r
EFI_HANDLE                  mMetronomeHandle = NULL;\r
\r
//\r
// The Metronome Architectural Protocol instance produced by this driver\r
//\r
EFI_METRONOME_ARCH_PROTOCOL mMetronome = {\r
  WaitForTick,\r
  TICK_PERIOD\r
};\r
\r
//\r
// The CPU I/O Protocol used to access system hardware\r
//\r
EFI_CPU_IO_PROTOCOL         *mCpuIo = NULL;\r
\r
//\r
// Worker Functions\r
//\r
\r
/**\r
  Write an 8 bit value to an I/O port and save it to the S3 script\r
\r
  @param Port  IO Port\r
  @param Data  Data in IO Port\r
\r
  @retval None.\r
\r
**/\r
VOID\r
ScriptWriteIo8 (\r
  UINT16  Port,\r
  UINT8   Data\r
  )\r
{\r
  mCpuIo->Io.Write (\r
               mCpuIo,\r
               EfiCpuIoWidthUint8,\r
               Port,\r
               1,\r
               &Data\r
               );\r
\r
}\r
\r
/**\r
\r
  Read the refresh bit from the REFRESH_PORT\r
\r
  @param None.\r
\r
  @retval Refresh bit.\r
\r
**/\r
UINT8\r
ReadRefresh (\r
  VOID\r
  )\r
{\r
  UINT8 Data;\r
\r
  mCpuIo->Io.Read (\r
               mCpuIo,\r
               EfiCpuIoWidthUint8,\r
               REFRESH_PORT,\r
               1,\r
               &Data\r
               );\r
  return (UINT8) (Data & REFRESH_ON);\r
}\r
\r
/**\r
\r
  Waits for the TickNumber of ticks from a known platform time source.\r
\r
  @param This                Pointer to the protocol instance.\r
  @param TickNumber          Tick Number to be waited\r
\r
\r
  @retval EFI_SUCCESS         If number of ticks occurred.\r
  @retval EFI_NOT_FOUND       Could not locate CPU IO protocol\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
WaitForTick (\r
  IN EFI_METRONOME_ARCH_PROTOCOL  *This,\r
  IN UINT32                       TickNumber\r
  )\r
{\r
  //\r
  // Wait for TickNumber toggles of the Refresh bit\r
  //\r
  for (; TickNumber != 0x00; TickNumber--) {\r
    while (ReadRefresh () == REFRESH_ON)\r
      ;\r
    while (ReadRefresh () == REFRESH_OFF)\r
      ;\r
  }\r
\r
  return EFI_SUCCESS;\r
}\r
\r
//\r
// Driver Entry Point\r
//\r
/**\r
  Install the LegacyMetronome driver.  Loads a Metronome Arch Protocol based\r
  on the Port 61 timer.\r
\r
  @param ImageHandle      Handle for the image of this driver\r
  @param SystemTable      Pointer to the EFI System Table\r
\r
  @retval EFI_SUCCESS     Metronome Architectural Protocol Installed\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
InstallLegacyMetronome (\r
  IN EFI_HANDLE        ImageHandle,\r
  IN EFI_SYSTEM_TABLE  *SystemTable\r
  )\r
{\r
  EFI_STATUS  Status;\r
\r
  //\r
  // Make sure the Metronome Architectural Protocol is not already installed in the system\r
  //\r
  ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiMetronomeArchProtocolGuid);\r
\r
  //\r
  // Get the CPU I/O Protocol that this driver requires\r
  // If the CPU I/O Protocol is not found, then ASSERT because the dependency expression\r
  // should guarantee that it is present in the handle database.\r
  //\r
  Status = gBS->LocateProtocol (\r
                  &gEfiCpuIoProtocolGuid,\r
                  NULL,\r
                  (void **)&mCpuIo\r
                  );\r
  ASSERT_EFI_ERROR (Status);\r
\r
  //\r
  // Program port 61 timer 1 as refresh timer. We could use ACPI timer in the\r
  // future.\r
  //\r
  ScriptWriteIo8 (TIMER1_CONTROL_PORT, LOAD_COUNTER1_LSB);\r
  ScriptWriteIo8 (TIMER1_COUNT_PORT, COUNTER1_COUNT);\r
\r
  //\r
  // Install on a new handle\r
  //\r
  Status = gBS->InstallMultipleProtocolInterfaces (\r
                  &mMetronomeHandle,\r
                  &gEfiMetronomeArchProtocolGuid,\r
                  &mMetronome,\r
                  NULL\r
                  );\r
  ASSERT_EFI_ERROR (Status);\r
\r
  return Status;\r
}\r