OvmfPkg/Library/AcpiTimerLib/BaseAcpiTimerLibBhyve.c

   1 /** @file
   2   Provide InternalAcpiGetTimerTick for the bhyve instance of the
   3   Base ACPI Timer Library
   4
   5   Copyright (C) 2020, Rebecca Cran <rebecca@bsdio.com>
   6   Copyright (C) 2014, Gabriel L. Somlo <somlo@cmu.edu>
   7
   8   SPDX-License-Identifier: BSD-2-Clause-Patent
   9 **/
  10
  11 #include <Library/IoLib.h>
  12 #include <OvmfPlatforms.h>
  13
  14 /**
  15   Internal function to read the current tick counter of ACPI.
  16
  17   Read the current ACPI tick counter using the counter address cached
  18   by this instance's constructor.
  19
  20   @return The tick counter read.
  21
  22 **/
  23 UINT32
  24 InternalAcpiGetTimerTick (
  25   VOID
  26   )
  27 {
  28   //
  29   // Return the current ACPI timer value.
  30   //
  31   return IoRead32 (BHYVE_ACPI_TIMER_IO_ADDR);
  32 }