mirror of https://github.com/acidanthera/audk.git
65 lines
1.6 KiB
C
65 lines
1.6 KiB
C
/** @file
|
|
Internal function to get spin lock alignment.
|
|
|
|
Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
|
|
This program and the accompanying materials
|
|
are licensed and made available under the terms and conditions of the BSD License
|
|
which accompanies this distribution. The full text of the license may be found at
|
|
http://opensource.org/licenses/bsd-license.php.
|
|
|
|
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
|
|
|
|
**/
|
|
|
|
#include "BaseSynchronizationLibInternals.h"
|
|
|
|
/**
|
|
Internal function to retrieve the architecture specific spin lock alignment
|
|
requirements for optimal spin lock performance.
|
|
|
|
@return The architecture specific spin lock alignment.
|
|
|
|
**/
|
|
UINTN
|
|
InternalGetSpinLockProperties (
|
|
VOID
|
|
)
|
|
{
|
|
UINT32 RegEax;
|
|
UINT32 RegEbx;
|
|
UINTN FamilyId;
|
|
UINTN ModelId;
|
|
UINTN CacheLineSize;
|
|
|
|
//
|
|
// Retrieve CPUID Version Information
|
|
//
|
|
AsmCpuid (0x01, &RegEax, &RegEbx, NULL, NULL);
|
|
//
|
|
// EBX: Bits 15 - 08: CLFLUSH line size (Value * 8 = cache line size)
|
|
//
|
|
CacheLineSize = ((RegEbx >> 8) & 0xff) * 8;
|
|
//
|
|
// Retrieve CPU Family and Model
|
|
//
|
|
FamilyId = (RegEax >> 8) & 0xf;
|
|
ModelId = (RegEax >> 4) & 0xf;
|
|
if (FamilyId == 0x0f) {
|
|
//
|
|
// In processors based on Intel NetBurst microarchitecture, use two cache lines
|
|
//
|
|
ModelId = ModelId | ((RegEax >> 12) & 0xf0);
|
|
if (ModelId <= 0x04 || ModelId == 0x06) {
|
|
CacheLineSize *= 2;
|
|
}
|
|
}
|
|
|
|
if (CacheLineSize < 32) {
|
|
CacheLineSize = 32;
|
|
}
|
|
|
|
return CacheLineSize;
|
|
}
|
|
|