OvmfPkg/SmmAccess/SmramInternal.h

   1 /** @file
   2
   3   Functions and types shared by the SMM accessor PEI and DXE modules.
   4
   5   Copyright (C) 2015, Red Hat, Inc.
   6
   7   This program and the accompanying materials are licensed and made available
   8   under the terms and conditions of the BSD License which accompanies this
   9   distribution. The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
  13   WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #include <Pi/PiMultiPhase.h>
  18
  19 //
  20 // We'll have two SMRAM ranges.
  21 //
  22 // The first is a tiny one that hosts an SMM_S3_RESUME_STATE object, to be
  23 // filled in by the CPU SMM driver during normal boot, for the PEI instance of
  24 // the LockBox library (which will rely on the object during S3 resume).
  25 //
  26 // The other SMRAM range is the main one, for the SMM core and the SMM drivers.
  27 //
  28 typedef enum {
  29   DescIdxSmmS3ResumeState = 0,
  30   DescIdxMain             = 1,
  31   DescIdxCount            = 2
  32 } DESCRIPTOR_INDEX;
  33
  34 //
  35 // The value of PcdQ35TsegMbytes is saved into this variable at module startup.
  36 //
  37 extern UINT16 mQ35TsegMbytes;
  38
  39 /**
  40   Save PcdQ35TsegMbytes into mQ35TsegMbytes.
  41 **/
  42 VOID
  43 InitQ35TsegMbytes (
  44   VOID
  45   );
  46
  47 /**
  48   Read the MCH_SMRAM and ESMRAMC registers, and update the LockState and
  49   OpenState fields in the PEI_SMM_ACCESS_PPI / EFI_SMM_ACCESS2_PROTOCOL object,
  50   from the D_LCK and T_EN bits.
  51
  52   PEI_SMM_ACCESS_PPI and EFI_SMM_ACCESS2_PROTOCOL member functions can rely on
  53   the LockState and OpenState fields being up-to-date on entry, and they need
  54   to restore the same invariant on exit, if they touch the bits in question.
  55
  56   @param[out] LockState  Reflects the D_LCK bit on output; TRUE iff SMRAM is
  57                          locked.
  58   @param[out] OpenState  Reflects the inverse of the T_EN bit on output; TRUE
  59                          iff SMRAM is open.
  60 **/
  61 VOID
  62 GetStates (
  63   OUT BOOLEAN *LockState,
  64   OUT BOOLEAN *OpenState
  65   );
  66
  67 //
  68 // The functions below follow the PEI_SMM_ACCESS_PPI and
  69 // EFI_SMM_ACCESS2_PROTOCOL member declarations. The PeiServices and This
  70 // pointers are removed (TSEG doesn't depend on them), and so is the
  71 // DescriptorIndex parameter (TSEG doesn't support range-wise locking).
  72 //
  73 // The LockState and OpenState members that are common to both
  74 // PEI_SMM_ACCESS_PPI and EFI_SMM_ACCESS2_PROTOCOL are taken and updated in
  75 // isolation from the rest of the (non-shared) members.
  76 //
  77
  78 EFI_STATUS
  79 SmramAccessOpen (
  80   OUT BOOLEAN *LockState,
  81   OUT BOOLEAN *OpenState
  82   );
  83
  84 EFI_STATUS
  85 SmramAccessClose (
  86   OUT BOOLEAN *LockState,
  87   OUT BOOLEAN *OpenState
  88   );
  89
  90 EFI_STATUS
  91 SmramAccessLock (
  92   OUT    BOOLEAN *LockState,
  93   IN OUT BOOLEAN *OpenState
  94   );
  95
  96 EFI_STATUS
  97 SmramAccessGetCapabilities (
  98   IN BOOLEAN                  LockState,
  99   IN BOOLEAN                  OpenState,
 100   IN OUT UINTN                *SmramMapSize,
 101   IN OUT EFI_SMRAM_DESCRIPTOR *SmramMap
 102   );