OvmfPkg/Csm/LegacyBiosDxe: Fix Legacy16GetTableAddress call for E820 data

[mirror_edk2.git] / OvmfPkg / SmmControl2Dxe / SmiFeatures.c

/**@file\r
  Negotiate SMI features with QEMU, and configure UefiCpuPkg/PiSmmCpuDxeSmm\r
  accordingly.\r
\r
  Copyright (C) 2016-2017, Red Hat, Inc.\r
\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
**/\r
\r
#include <Library/BaseLib.h>\r
#include <Library/DebugLib.h>\r
#include <Library/MemoryAllocationLib.h>\r
#include <Library/PcdLib.h>\r
#include <Library/QemuFwCfgLib.h>\r
#include <Library/QemuFwCfgS3Lib.h>\r
\r
#include "SmiFeatures.h"\r
\r
//\r
// The following bit value stands for "broadcast SMI" in the\r
// "etc/smi/supported-features" and "etc/smi/requested-features" fw_cfg files.\r
//\r
#define ICH9_LPC_SMI_F_BROADCAST BIT0\r
\r
//\r
// Provides a scratch buffer (allocated in EfiReservedMemoryType type memory)\r
// for the S3 boot script fragment to write to and read from.\r
//\r
#pragma pack (1)\r
typedef union {\r
  UINT64 Features;\r
  UINT8  FeaturesOk;\r
} SCRATCH_BUFFER;\r
#pragma pack ()\r
\r
//\r
// These carry the selector keys of the "etc/smi/requested-features" and\r
// "etc/smi/features-ok" fw_cfg files from NegotiateSmiFeatures() to\r
// AppendFwCfgBootScript().\r
//\r
STATIC FIRMWARE_CONFIG_ITEM mRequestedFeaturesItem;\r
STATIC FIRMWARE_CONFIG_ITEM mFeaturesOkItem;\r
\r
//\r
// Carries the negotiated SMI features from NegotiateSmiFeatures() to\r
// AppendFwCfgBootScript().\r
//\r
STATIC UINT64 mSmiFeatures;\r
\r
/**\r
  Negotiate SMI features with QEMU.\r
\r
  @retval FALSE  If SMI feature negotiation is not supported by QEMU. This is\r
                 not an error, it just means that SaveSmiFeatures() should not\r
                 be called.\r
\r
  @retval TRUE   SMI feature negotiation is supported, and it has completed\r
                 successfully as well. (Failure to negotiate is a fatal error\r
                 and the function never returns in that case.)\r
**/\r
BOOLEAN\r
NegotiateSmiFeatures (\r
  VOID\r
  )\r
{\r
  FIRMWARE_CONFIG_ITEM SupportedFeaturesItem;\r
  UINTN                SupportedFeaturesSize;\r
  UINTN                RequestedFeaturesSize;\r
  UINTN                FeaturesOkSize;\r
\r
  //\r
  // Look up the fw_cfg files used for feature negotiation. The selector keys\r
  // of "etc/smi/requested-features" and "etc/smi/features-ok" are saved\r
  // statically. If the files are missing, then QEMU doesn't support SMI\r
  // feature negotiation.\r
  //\r
  if (RETURN_ERROR (QemuFwCfgFindFile ("etc/smi/supported-features",\r
                      &SupportedFeaturesItem, &SupportedFeaturesSize)) ||\r
      RETURN_ERROR (QemuFwCfgFindFile ("etc/smi/requested-features",\r
                      &mRequestedFeaturesItem, &RequestedFeaturesSize)) ||\r
      RETURN_ERROR (QemuFwCfgFindFile ("etc/smi/features-ok",\r
                      &mFeaturesOkItem, &FeaturesOkSize))) {\r
    DEBUG ((DEBUG_INFO, "%a: SMI feature negotiation unavailable\n",\r
      __FUNCTION__));\r
    return FALSE;\r
  }\r
\r
  //\r
  // If the files are present but their sizes disagree with us, that's a fatal\r
  // error (we can't trust the behavior of SMIs either way).\r
  //\r
  if (SupportedFeaturesSize != sizeof mSmiFeatures ||\r
      RequestedFeaturesSize != sizeof mSmiFeatures ||\r
      FeaturesOkSize != sizeof (UINT8)) {\r
    DEBUG ((DEBUG_ERROR, "%a: size mismatch in feature negotiation\n",\r
      __FUNCTION__));\r
    goto FatalError;\r
  }\r
\r
  //\r
  // Get the features supported by the host.\r
  //\r
  QemuFwCfgSelectItem (SupportedFeaturesItem);\r
  QemuFwCfgReadBytes (sizeof mSmiFeatures, &mSmiFeatures);\r
\r
  //\r
  // We want broadcast SMI and nothing else.\r
  //\r
  mSmiFeatures &= ICH9_LPC_SMI_F_BROADCAST;\r
  QemuFwCfgSelectItem (mRequestedFeaturesItem);\r
  QemuFwCfgWriteBytes (sizeof mSmiFeatures, &mSmiFeatures);\r
\r
  //\r
  // Invoke feature validation in QEMU. If the selection is accepted, the\r
  // features will be locked down. If the selection is rejected, feature\r
  // negotiation remains open; however we don't know what to do in that case,\r
  // so that's a fatal error.\r
  //\r
  QemuFwCfgSelectItem (mFeaturesOkItem);\r
  if (QemuFwCfgRead8 () != 1) {\r
    DEBUG ((DEBUG_ERROR, "%a: negotiation failed for feature bitmap 0x%Lx\n",\r
      __FUNCTION__, mSmiFeatures));\r
    goto FatalError;\r
  }\r
\r
  if ((mSmiFeatures & ICH9_LPC_SMI_F_BROADCAST) == 0) {\r
    //\r
    // If we can't get broadcast SMIs from QEMU, that's acceptable too,\r
    // although not optimal.\r
    //\r
    DEBUG ((DEBUG_INFO, "%a: SMI broadcast unavailable\n", __FUNCTION__));\r
  } else {\r
    //\r
    // Configure the traditional AP sync / SMI delivery mode for\r
    // PiSmmCpuDxeSmm. Effectively, restore the UefiCpuPkg defaults, from which\r
    // the original QEMU behavior (i.e., unicast SMI) used to differ.\r
    //\r
    if (RETURN_ERROR (PcdSet64S (PcdCpuSmmApSyncTimeout, 1000000)) ||\r
        RETURN_ERROR (PcdSet8S (PcdCpuSmmSyncMode, 0x00))) {\r
      DEBUG ((DEBUG_ERROR, "%a: PiSmmCpuDxeSmm PCD configuration failed\n",\r
        __FUNCTION__));\r
      goto FatalError;\r
    }\r
    DEBUG ((DEBUG_INFO, "%a: using SMI broadcast\n", __FUNCTION__));\r
  }\r
\r
  //\r
  // Negotiation successful (although we may not have gotten the optimal\r
  // feature set).\r
  //\r
  return TRUE;\r
\r
FatalError:\r
  ASSERT (FALSE);\r
  CpuDeadLoop ();\r
  //\r
  // Keep the compiler happy.\r
  //\r
  return FALSE;\r
}\r
\r
/**\r
  FW_CFG_BOOT_SCRIPT_CALLBACK_FUNCTION provided to QemuFwCfgS3Lib.\r
**/\r
STATIC\r
VOID\r
EFIAPI\r
AppendFwCfgBootScript (\r
  IN OUT VOID *Context,              OPTIONAL\r
  IN OUT VOID *ExternalScratchBuffer\r
  )\r
{\r
  SCRATCH_BUFFER *ScratchBuffer;\r
  RETURN_STATUS  Status;\r
\r
  ScratchBuffer = ExternalScratchBuffer;\r
\r
  //\r
  // Write the negotiated feature bitmap into "etc/smi/requested-features".\r
  //\r
  ScratchBuffer->Features = mSmiFeatures;\r
  Status = QemuFwCfgS3ScriptWriteBytes (mRequestedFeaturesItem,\r
             sizeof ScratchBuffer->Features);\r
  if (RETURN_ERROR (Status)) {\r
    goto FatalError;\r
  }\r
\r
  //\r
  // Read back "etc/smi/features-ok". This invokes the feature validation &\r
  // lockdown. (The validation succeeded at first boot.)\r
  //\r
  Status = QemuFwCfgS3ScriptReadBytes (mFeaturesOkItem,\r
             sizeof ScratchBuffer->FeaturesOk);\r
  if (RETURN_ERROR (Status)) {\r
    goto FatalError;\r
  }\r
\r
  //\r
  // If "etc/smi/features-ok" read as 1, we're good. Otherwise, hang the S3\r
  // resume process.\r
  //\r
  Status = QemuFwCfgS3ScriptCheckValue (&ScratchBuffer->FeaturesOk,\r
             sizeof ScratchBuffer->FeaturesOk, MAX_UINT8, 1);\r
  if (RETURN_ERROR (Status)) {\r
    goto FatalError;\r
  }\r
\r
  DEBUG ((DEBUG_VERBOSE, "%a: SMI feature negotiation boot script saved\n",\r
    __FUNCTION__));\r
  return;\r
\r
FatalError:\r
  ASSERT (FALSE);\r
  CpuDeadLoop ();\r
}\r
\r
\r
/**\r
  Append a boot script fragment that will re-select the previously negotiated\r
  SMI features during S3 resume.\r
**/\r
VOID\r
SaveSmiFeatures (\r
  VOID\r
  )\r
{\r
  RETURN_STATUS Status;\r
\r
  //\r
  // We are already running at TPL_CALLBACK, on the stack of\r
  // OnS3SaveStateInstalled(). But that's okay, we can easily queue more\r
  // notification functions while executing a notification function.\r
  //\r
  Status = QemuFwCfgS3CallWhenBootScriptReady (AppendFwCfgBootScript, NULL,\r
             sizeof (SCRATCH_BUFFER));\r
  if (RETURN_ERROR (Status)) {\r
    ASSERT (FALSE);\r
    CpuDeadLoop ();\r
  }\r
}\r