d4dd22c7bc
The declaration and the definition(s) of the function should have identical leading comments and/or identical parameter lists. Also remove any excess space in the comment block, and unindent the trailing "**/" if necessary. Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Jordan Justen <jordan.l.justen@intel.com> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Laszlo Ersek <lersek@redhat.com> Tested-by: Brijesh Singh <brijesh.singh@amd.com> Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
90 lines
2.1 KiB
C
90 lines
2.1 KiB
C
/** @file
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Secure Encrypted Virtualization (SEV) library helper function
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Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
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This program and the accompanying materials are licensed and made available
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under the terms and conditions of the BSD License which accompanies this
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distribution. The full text of the license may be found at
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http://opensource.org/licenses/bsd-license.php
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THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
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WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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**/
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#include <Library/BaseLib.h>
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#include <Library/DebugLib.h>
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#include <Register/Cpuid.h>
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#include <Register/Amd/Cpuid.h>
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#include <Register/Amd/Msr.h>
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#include <Library/MemEncryptSevLib.h>
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STATIC BOOLEAN mSevStatus = FALSE;
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STATIC BOOLEAN mSevStatusChecked = FALSE;
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/**
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Returns a boolean to indicate whether SEV is enabled
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@retval TRUE SEV is enabled
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@retval FALSE SEV is not enabled
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**/
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STATIC
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BOOLEAN
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EFIAPI
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InternalMemEncryptSevIsEnabled (
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VOID
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)
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{
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UINT32 RegEax;
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MSR_SEV_STATUS_REGISTER Msr;
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CPUID_MEMORY_ENCRYPTION_INFO_EAX Eax;
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//
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// Check if memory encryption leaf exist
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//
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AsmCpuid (CPUID_EXTENDED_FUNCTION, &RegEax, NULL, NULL, NULL);
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if (RegEax >= CPUID_MEMORY_ENCRYPTION_INFO) {
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//
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// CPUID Fn8000_001F[EAX] Bit 1 (Sev supported)
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//
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AsmCpuid (CPUID_MEMORY_ENCRYPTION_INFO, &Eax.Uint32, NULL, NULL, NULL);
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if (Eax.Bits.SevBit) {
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//
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// Check MSR_0xC0010131 Bit 0 (Sev Enabled)
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//
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Msr.Uint32 = AsmReadMsr32 (MSR_SEV_STATUS);
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if (Msr.Bits.SevBit) {
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return TRUE;
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}
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}
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}
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return FALSE;
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}
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/**
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Returns a boolean to indicate whether SEV is enabled
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@retval TRUE SEV is enabled
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@retval FALSE SEV is not enabled
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**/
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BOOLEAN
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EFIAPI
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MemEncryptSevIsEnabled (
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VOID
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)
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{
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if (mSevStatusChecked) {
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return mSevStatus;
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}
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mSevStatus = InternalMemEncryptSevIsEnabled();
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mSevStatusChecked = TRUE;
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return mSevStatus;
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}
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