X86Cache.c

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#include <Base.h>
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
 
VOID
EFIAPI
InvalidateInstructionCache (
  VOID
  )
{
}
 
VOID *
EFIAPI
InvalidateInstructionCacheRange (
  IN      VOID   *Address,
  IN      UINTN  Length
  )
{
  if (Length == 0) {
    return Address;
  }
 
  ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)Address));
  return Address;
}
 
VOID
EFIAPI
WriteBackInvalidateDataCache (
  VOID
  )
{
  AsmWbinvd ();
}
 
VOID *
EFIAPI
WriteBackInvalidateDataCacheRange (
  IN      VOID   *Address,
  IN      UINTN  Length
  )
{
  UINT32  RegEbx;
  UINT32  RegEdx;
  UINTN   CacheLineSize;
  UINTN   Start;
  UINTN   End;
 
  if (Length == 0) {
    return Address;
  }
 
  ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)Address));
 
  //
  // If the CPU does not support CLFLUSH instruction,
  // then promote flush range to flush entire cache.
  //
  AsmCpuid (0x01, NULL, &RegEbx, NULL, &RegEdx);
  if ((RegEdx & BIT19) == 0) {
    AsmWbinvd ();
    return Address;
  }
 
  //
  // Cache line size is 8 * Bits 15-08 of EBX returned from CPUID 01H
  //
  CacheLineSize = (RegEbx & 0xff00) >> 5;
 
  Start = (UINTN)Address;
  //
  // Calculate the cache line alignment
  //
  End    = (Start + Length + (CacheLineSize - 1)) & ~(CacheLineSize - 1);
  Start &= ~((UINTN)CacheLineSize - 1);
 
  do {
    Start = (UINTN)AsmFlushCacheLine ((VOID *)Start) + CacheLineSize;
  } while (Start != End);
 
  return Address;
}
 
VOID
EFIAPI
WriteBackDataCache (
  VOID
  )
{
  WriteBackInvalidateDataCache ();
}
 
VOID *
EFIAPI
WriteBackDataCacheRange (
  IN      VOID   *Address,
  IN      UINTN  Length
  )
{
  return WriteBackInvalidateDataCacheRange (Address, Length);
}
 
VOID
EFIAPI
InvalidateDataCache (
  VOID
  )
{
  AsmInvd ();
}
 
VOID *
EFIAPI
InvalidateDataCacheRange (
  IN      VOID   *Address,
  IN      UINTN  Length
  )
{
  //
  // Invalidation of a data cache range without writing back is not supported on
  // x86 architecture, so write back and invalidate operation is performed.
  //
  return WriteBackInvalidateDataCacheRange (Address, Length);
}