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   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #include <Pi/PiMultiPhase.h>
  12
  13 //
  14 // We'll have two SMRAM ranges.
  15 //
  16 // The first is a tiny one that hosts an SMM_S3_RESUME_STATE object, to be
  17 // filled in by the CPU SMM driver during normal boot, for the PEI instance of
  18 // the LockBox library (which will rely on the object during S3 resume).
  19 //
  20 // The other SMRAM range is the main one, for the SMM core and the SMM drivers.
  21 //
  22 typedef enum {
  23   DescIdxSmmS3ResumeState = 0,
  24   DescIdxMain             = 1,
  25   DescIdxCount            = 2
  26 } DESCRIPTOR_INDEX;
  27
  28 //
  29 // The value of PcdQ35TsegMbytes is saved into this variable at module startup.
  30 //
  31 extern UINT16 mQ35TsegMbytes;
  32
  33 /**
  34   Save PcdQ35TsegMbytes into mQ35TsegMbytes.
  35 **/
  36 VOID
  37 InitQ35TsegMbytes (
  38   VOID
  39   );
  40
  41 /**
  42   Read the MCH_SMRAM and ESMRAMC registers, and update the LockState and
  43   OpenState fields in the PEI_SMM_ACCESS_PPI / EFI_SMM_ACCESS2_PROTOCOL object,
  44   from the D_LCK and T_EN bits.
  45
  46   PEI_SMM_ACCESS_PPI and EFI_SMM_ACCESS2_PROTOCOL member functions can rely on
  47   the LockState and OpenState fields being up-to-date on entry, and they need
  48   to restore the same invariant on exit, if they touch the bits in question.
  49
  50   @param[out] LockState  Reflects the D_LCK bit on output; TRUE iff SMRAM is
  51                          locked.
  52   @param[out] OpenState  Reflects the inverse of the T_EN bit on output; TRUE
  53                          iff SMRAM is open.
  54 **/
  55 VOID
  56 GetStates (
  57   OUT BOOLEAN *LockState,
  58   OUT BOOLEAN *OpenState
  59   );
  60
  61 //
  62 // The functions below follow the PEI_SMM_ACCESS_PPI and
  63 // EFI_SMM_ACCESS2_PROTOCOL member declarations. The PeiServices and This
  64 // pointers are removed (TSEG doesn't depend on them), and so is the
  65 // DescriptorIndex parameter (TSEG doesn't support range-wise locking).
  66 //
  67 // The LockState and OpenState members that are common to both
  68 // PEI_SMM_ACCESS_PPI and EFI_SMM_ACCESS2_PROTOCOL are taken and updated in
  69 // isolation from the rest of the (non-shared) members.
  70 //
  71
  72 EFI_STATUS
  73 SmramAccessOpen (
  74   OUT BOOLEAN *LockState,
  75   OUT BOOLEAN *OpenState
  76   );
  77
  78 EFI_STATUS
  79 SmramAccessClose (
  80   OUT BOOLEAN *LockState,
  81   OUT BOOLEAN *OpenState
  82   );
  83
  84 EFI_STATUS
  85 SmramAccessLock (
  86   OUT    BOOLEAN *LockState,
  87   IN OUT BOOLEAN *OpenState
  88   );
  89
  90 EFI_STATUS
  91 SmramAccessGetCapabilities (
  92   IN BOOLEAN                  LockState,
  93   IN BOOLEAN                  OpenState,
  94   IN OUT UINTN                *SmramMapSize,
  95   IN OUT EFI_SMRAM_DESCRIPTOR *SmramMap
  96   );