1 files changed, 58 insertions, 0 deletions
diff --git a/src/VBox/Devices/EFI/Firmware/UefiCpuPkg/Library/CpuCommonFeaturesLib/FastStrings.c b/src/VBox/Devices/EFI/Firmware/UefiCpuPkg/Library/CpuCommonFeaturesLib/FastStrings.c
new file mode 100644
index 00000000..e0a17a70
--- /dev/null
+++ b/src/VBox/Devices/EFI/Firmware/UefiCpuPkg/Library/CpuCommonFeaturesLib/FastStrings.c
@@ -0,0 +1,58 @@
+/** @file
+  Fast-Strings feature.
+
+  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "CpuCommonFeatures.h"
+
+/**
+  Initializes Fast-Strings feature to specific state.
+
+  @param[in]  ProcessorNumber  The index of the CPU executing this function.
+  @param[in]  CpuInfo          A pointer to the REGISTER_CPU_FEATURE_INFORMATION
+                               structure for the CPU executing this function.
+  @param[in]  ConfigData       A pointer to the configuration buffer returned
+                               by CPU_FEATURE_GET_CONFIG_DATA.  NULL if
+                               CPU_FEATURE_GET_CONFIG_DATA was not provided in
+                               RegisterCpuFeature().
+  @param[in]  State            If TRUE, then the Fast-Strings feature must be enabled.
+                               If FALSE, then the Fast-Strings feature must be disabled.
+
+  @retval RETURN_SUCCESS       Fast-Strings feature is initialized.
+
+  @note This service could be called by BSP only.
+**/
+RETURN_STATUS
+EFIAPI
+FastStringsInitialize (
+  IN UINTN                             ProcessorNumber,
+  IN REGISTER_CPU_FEATURE_INFORMATION  *CpuInfo,
+  IN VOID                              *ConfigData,  OPTIONAL
+  IN BOOLEAN                           State
+  )
+{
+  //
+  // The scope of FastStrings bit in the MSR_IA32_MISC_ENABLE is core for below processor type, only program
+  // MSR_IA32_MISC_ENABLE for thread 0 in each core.
+  //
+  if (IS_SILVERMONT_PROCESSOR (CpuInfo->DisplayFamily, CpuInfo->DisplayModel) ||
+      IS_GOLDMONT_PROCESSOR (CpuInfo->DisplayFamily, CpuInfo->DisplayModel) ||
+      IS_PENTIUM_4_PROCESSOR (CpuInfo->DisplayFamily, CpuInfo->DisplayModel)) {
+    if (CpuInfo->ProcessorInfo.Location.Thread != 0) {
+      return RETURN_SUCCESS;
+    }
+  }
+
+  CPU_REGISTER_TABLE_WRITE_FIELD (
+    ProcessorNumber,
+    Msr,
+    MSR_IA32_MISC_ENABLE,
+    MSR_IA32_MISC_ENABLE_REGISTER,
+    Bits.FastStrings,
+    (State) ? 1 : 0
+    );
+  return RETURN_SUCCESS;
+}