MdeModulePkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / MdeModulePkg / Core / Dxe / Event / Tpl.c

/** @file\r
  Task priority (TPL) functions.\r
\r
Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "DxeMain.h"\r
#include "Event.h"\r
\r
/**\r
  Set Interrupt State.\r
\r
  @param  Enable  The state of enable or disable interrupt\r
\r
**/\r
VOID\r
CoreSetInterruptState (\r
  IN BOOLEAN      Enable\r
  )\r
{\r
  EFI_STATUS  Status;\r
  BOOLEAN     InSmm;\r
\r
  if (gCpu == NULL) {\r
    return;\r
  }\r
  if (!Enable) {\r
    gCpu->DisableInterrupt (gCpu);\r
    return;\r
  }\r
  if (gSmmBase2 == NULL) {\r
    gCpu->EnableInterrupt (gCpu);\r
    return;\r
  }\r
  Status = gSmmBase2->InSmm (gSmmBase2, &InSmm);\r
  if (!EFI_ERROR (Status) && !InSmm) {\r
    gCpu->EnableInterrupt(gCpu);\r
  }\r
}\r
\r
\r
/**\r
  Raise the task priority level to the new level.\r
  High level is implemented by disabling processor interrupts.\r
\r
  @param  NewTpl  New task priority level\r
\r
  @return The previous task priority level\r
\r
**/\r
EFI_TPL\r
EFIAPI\r
CoreRaiseTpl (\r
  IN EFI_TPL      NewTpl\r
  )\r
{\r
  EFI_TPL     OldTpl;\r
\r
  OldTpl = gEfiCurrentTpl;\r
  if (OldTpl > NewTpl) {\r
    DEBUG ((EFI_D_ERROR, "FATAL ERROR - RaiseTpl with OldTpl(0x%x) > NewTpl(0x%x)\n", OldTpl, NewTpl));\r
    ASSERT (FALSE);\r
  }\r
  ASSERT (VALID_TPL (NewTpl));\r
\r
  //\r
  // If raising to high level, disable interrupts\r
  //\r
  if (NewTpl >= TPL_HIGH_LEVEL  &&  OldTpl < TPL_HIGH_LEVEL) {\r
    CoreSetInterruptState (FALSE);\r
  }\r
\r
  //\r
  // Set the new value\r
  //\r
  gEfiCurrentTpl = NewTpl;\r
\r
  return OldTpl;\r
}\r
\r
\r
\r
\r
/**\r
  Lowers the task priority to the previous value.   If the new\r
  priority unmasks events at a higher priority, they are dispatched.\r
\r
  @param  NewTpl  New, lower, task priority\r
\r
**/\r
VOID\r
EFIAPI\r
CoreRestoreTpl (\r
  IN EFI_TPL NewTpl\r
  )\r
{\r
  EFI_TPL     OldTpl;\r
  EFI_TPL     PendingTpl;\r
\r
  OldTpl = gEfiCurrentTpl;\r
  if (NewTpl > OldTpl) {\r
    DEBUG ((EFI_D_ERROR, "FATAL ERROR - RestoreTpl with NewTpl(0x%x) > OldTpl(0x%x)\n", NewTpl, OldTpl));\r
    ASSERT (FALSE);\r
  }\r
  ASSERT (VALID_TPL (NewTpl));\r
\r
  //\r
  // If lowering below HIGH_LEVEL, make sure\r
  // interrupts are enabled\r
  //\r
\r
  if (OldTpl >= TPL_HIGH_LEVEL  &&  NewTpl < TPL_HIGH_LEVEL) {\r
    gEfiCurrentTpl = TPL_HIGH_LEVEL;\r
  }\r
\r
  //\r
  // Dispatch any pending events\r
  //\r
  while (gEventPending != 0) {\r
    PendingTpl = (UINTN) HighBitSet64 (gEventPending);\r
    if (PendingTpl <= NewTpl) {\r
      break;\r
    }\r
\r
    gEfiCurrentTpl = PendingTpl;\r
    if (gEfiCurrentTpl < TPL_HIGH_LEVEL) {\r
      CoreSetInterruptState (TRUE);\r
    }\r
    CoreDispatchEventNotifies (gEfiCurrentTpl);\r
  }\r
\r
  //\r
  // Set the new value\r
  //\r
\r
  gEfiCurrentTpl = NewTpl;\r
\r
  //\r
  // If lowering below HIGH_LEVEL, make sure\r
  // interrupts are enabled\r
  //\r
  if (gEfiCurrentTpl < TPL_HIGH_LEVEL) {\r
    CoreSetInterruptState (TRUE);\r
  }\r
\r
}\r