SourceLevelDebugPkg/DebugAgent: Disable Debug Timer as early

[mirror_edk2.git] / SourceLevelDebugPkg / Library / DebugAgent / DebugAgentCommon / DebugTimer.c

/** @file\r
  Code for debug timer to support debug agent library implementation.\r
\r
  Copyright (c) 2010 - 2015, Intel Corporation. All rights reserved.<BR>\r
  This program and the accompanying materials\r
  are licensed and made available under the terms and conditions of the BSD License\r
  which accompanies this distribution.  The full text of the license may be found at\r
  http://opensource.org/licenses/bsd-license.php.\r
\r
  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
**/\r
\r
#include "DebugAgent.h"\r
\r
/**\r
  Initialize CPU local APIC timer.\r
\r
  @param[out] TimerFrequency  Local APIC timer frequency returned.\r
  @param[in]  DumpFlag        If TRUE, dump Local APIC timer's parameter.\r
 \r
  @return   32-bit Local APIC timer init count.\r
**/\r
UINT32\r
InitializeDebugTimer (\r
  OUT UINT32     *TimerFrequency,\r
  IN  BOOLEAN    DumpFlag\r
  )\r
{\r
  UINTN       ApicTimerDivisor;\r
  UINT32      InitialCount;\r
  UINT32      ApicTimerFrequency;\r
\r
  GetApicTimerState (&ApicTimerDivisor, NULL, NULL);\r
  ApicTimerFrequency = PcdGet32(PcdFSBClock) / (UINT32)ApicTimerDivisor;\r
  //\r
  // Cpu Local Apic timer interrupt frequency, it is set to 0.1s\r
  //\r
  InitialCount = (UINT32)DivU64x32 (\r
                   MultU64x64 (\r
                     ApicTimerFrequency,\r
                     DEBUG_TIMER_INTERVAL\r
                     ),\r
                   1000000u\r
                   );\r
\r
  InitializeApicTimer (ApicTimerDivisor, InitialCount, TRUE, DEBUG_TIMER_VECTOR);\r
  //\r
  // Disable Debug Timer interrupt to avoid it is delivered before Debug Port\r
  // is initialized\r
  //\r
  DisableApicTimerInterrupt ();\r
\r
  if (DumpFlag) {\r
    DEBUG ((EFI_D_INFO, "Debug Timer: FSB Clock    = %d\n", PcdGet32(PcdFSBClock)));\r
    DEBUG ((EFI_D_INFO, "Debug Timer: Divisor      = %d\n", ApicTimerDivisor));\r
    DEBUG ((EFI_D_INFO, "Debug Timer: Frequency    = %d\n", ApicTimerFrequency));\r
    DEBUG ((EFI_D_INFO, "Debug Timer: InitialCount = %d\n", InitialCount));\r
  }\r
  if (TimerFrequency != NULL) {\r
    *TimerFrequency = ApicTimerFrequency;\r
  }\r
  return InitialCount;\r
}\r
\r
/**\r
  Enable/Disable the interrupt of debug timer and return the interrupt state\r
  prior to the operation.\r
\r
  If EnableStatus is TRUE, enable the interrupt of debug timer.\r
  If EnableStatus is FALSE, disable the interrupt of debug timer.\r
\r
  @param[in] EnableStatus    Enable/Disable.\r
\r
  @retval TRUE  Debug timer interrupt were enabled on entry to this call.\r
  @retval FALSE Debug timer interrupt were disabled on entry to this call.\r
\r
**/\r
BOOLEAN\r
EFIAPI\r
SaveAndSetDebugTimerInterrupt (\r
  IN BOOLEAN                EnableStatus\r
  )\r
{\r
  BOOLEAN     OldDebugTimerInterruptState;\r
\r
  OldDebugTimerInterruptState = GetApicTimerInterruptState ();\r
\r
  if (OldDebugTimerInterruptState != EnableStatus) {\r
    if (EnableStatus) {\r
      EnableApicTimerInterrupt ();\r
    } else {\r
      DisableApicTimerInterrupt ();\r
    }\r
    //\r
    // Validate the Debug Timer interrupt state\r
    // This will make additional delay after Local Apic Timer interrupt state is changed.\r
    // Thus, CPU could handle the potential pending interrupt of Local Apic timer.\r
    //\r
    while (GetApicTimerInterruptState () != EnableStatus) {\r
      CpuPause ();\r
    }\r
  }\r
\r
  return OldDebugTimerInterruptState;\r
}\r
\r
/**\r
  Check if the timer is time out.\r
  \r
  @param[in] TimerCycle             Timer total count.\r
  @param[in] Timer                  The start timer from the begin.\r
  @param[in] TimeoutTicker          Ticker number need time out.\r
\r
  @return TRUE  Timer time out occurs.\r
  @retval FALSE Timer does not time out.\r
\r
**/\r
BOOLEAN\r
IsDebugTimerTimeout (\r
  IN UINT32                     TimerCycle,\r
  IN UINT32                     Timer,\r
  IN UINT32                     TimeoutTicker\r
  )\r
{\r
  UINT64  CurrentTimer;\r
  UINT64  Delta;\r
\r
  CurrentTimer = GetApicTimerCurrentCount ();\r
\r
  //\r
  // This timer counter counts down.  Check for roll over condition.\r
  //\r
  if (CurrentTimer < Timer) {\r
    Delta = Timer - CurrentTimer;\r
  } else {\r
    //\r
    // Handle one roll-over. \r
    //\r
    Delta = TimerCycle - (CurrentTimer - Timer);\r
  }\r
 \r
  return (BOOLEAN) (Delta >= TimeoutTicker);\r
}\r
\r