VerifyMsrE2.c

Go to the documentation of this file.

 
#include <Uefi.h>
#include <PiDxe.h>
#include <Library/PcdLib.h>
#include <Library/UefiLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/OcMiscLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/UefiRuntimeServicesTableLib.h>
#include <Library/UefiApplicationEntryPoint.h>
#include <Register/Msr.h>
#include <Protocol/MpService.h>
 
STATIC EFI_MP_SERVICES_PROTOCOL  *mMpServices;
STATIC UINTN                     mHasLockedCores;
STATIC UINTN                     mHasUnlockedCores;
 
VOID
EFIAPI
ReadMsrE2 (
  IN  VOID  *Buffer
  )
{
  UINTN                                          ProcNum = 0;
  MSR_BROADWELL_PKG_CST_CONFIG_CONTROL_REGISTER  Value;
  EFI_STATUS                                     Status;
 
  Status = mMpServices->WhoAmI (mMpServices, &ProcNum);
 
  if (EFI_ERROR (Status)) {
    Print (L"Failed to detect CPU Number\n");
    return;
  }
 
  Value.Uint64 = AsmReadMsr64 (MSR_BROADWELL_PKG_CST_CONFIG_CONTROL);
 
  Print (L"CPU%02d has MSR 0xE2: 0x%016LX\n", ProcNum, Value.Uint64);
 
  if (Value.Bits.CFGLock) {
    mHasLockedCores = 1;
  } else {
    mHasUnlockedCores = 1;
  }
}
 
EFI_STATUS
EFIAPI
VerifyMSRE2 (
  VOID
  )
{
  EFI_STATUS  Status;
 
  Print (L"Looking up EFI_MP_SERVICES_PROTOCOL...\n");
 
  Status = gBS->LocateProtocol (&gEfiMpServiceProtocolGuid, NULL, (VOID **)&mMpServices);
  if (EFI_ERROR (Status)) {
    Print (L"Failed to find EFI_MP_SERVICES_PROTOCOL - %r\n", Status);
    return Status;
  }
 
  Print (L"Checking MSR 0xE2 on all CPUs. Values must be SAME!!!\n");
 
  ReadMsrE2 (NULL);
 
  Print (L"Starting All APs to verify 0xE2 register...\n", Status);
 
  Status = mMpServices->StartupAllAPs (mMpServices, ReadMsrE2, TRUE, NULL, 5000000, NULL, NULL);
  if (EFI_ERROR (Status)) {
    Print (L"Failed to StartupAllAPs - %r\n", Status);
    return Status;
  }
 
  Print (L"Done checking MSR 0xE2 register, compare the values printed!\n");
 
  if (mHasLockedCores && mHasUnlockedCores) {
    Print (L"This firmware has BORKED MSR 0xE2 register!\n");
    Print (L"Some cores are locked, some are not!!!\n");
  } else if (mHasUnlockedCores) {
    Print (L"This firmware has UNLOCKED MSR 0xE2 register!\n");
  } else {
    Print (L"This firmware has LOCKED MSR 0xE2 register!\n");
  }
 
  return EFI_SUCCESS;
}