From 54a3e8c9f57935ea95b9b255cb1ca59bbc03e6ea Mon Sep 17 00:00:00 2001
From: Jeff Fan <jeff.fan@intel.com>
Date: Fri, 18 Dec 2015 03:23:27 +0000
Subject: [PATCH] UefiCpuPkg: Add PCD PcdCpuApLoopMode

This new PCD is used to specify the AP loop mode during POST phase.

The value 1 means we will place AP in the Hlt-Loop state by HLT instruction.
BSP need to send INIT-SIPI-SIPI to wake up APs.

The value 2 means we will place AP in the deepest C-state by MWAIT instruction.
BSP need to modify the monitor buffer by MONITOR instruction to wake up APs.

The value 3 means we will place AP in the Run-loop state. APs are running.
BSP need to write one semaphore to wake up APs.

Contributed-under: TianoCore Contribution Agreement 1.0
Cc: Feng Tian <feng.tian@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Tested-by: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Michael Kinney <michael.d.kinney@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19341 6f19259b-4bc3-4df7-8a09-765794883524
---
 UefiCpuPkg/UefiCpuPkg.dec | 8 ++++++++
 UefiCpuPkg/UefiCpuPkg.uni | 4 ++++
 2 files changed, 12 insertions(+)

diff --git a/UefiCpuPkg/UefiCpuPkg.dec b/UefiCpuPkg/UefiCpuPkg.dec
index a694146689..0d42918427 100644
--- a/UefiCpuPkg/UefiCpuPkg.dec
+++ b/UefiCpuPkg/UefiCpuPkg.dec
@@ -182,6 +182,14 @@
   ## Specifies the size of the microcode Region.
   # @Prompt Microcode Region size.
   gUefiCpuPkgTokenSpaceGuid.PcdCpuMicrocodePatchRegionSize|0x0|UINT64|0x00000006
+  ## Specifies the AP wait loop state during POST phase.
+  #  The value is defined as below.<BR><BR>
+  #  1: Place AP in the Hlt-Loop state.<BR>
+  #  2: Place AP in the Mwait-Loop state.<BR>
+  #  3: Place AP in the Run-Loop state.<BR>
+  # @Prompt The AP wait loop state.
+  # @ValidRange  0x80000001 | 1 - 3
+  gUefiCpuPkgTokenSpaceGuid.PcdCpuApLoopMode|1|UINT8|0x60008006
 
 [PcdsDynamic, PcdsDynamicEx]
   ## Contains the pointer to a CPU S3 data buffer of structure ACPI_CPU_DATA.
diff --git a/UefiCpuPkg/UefiCpuPkg.uni b/UefiCpuPkg/UefiCpuPkg.uni
index fd1e81226a..2c74a92e06 100644
--- a/UefiCpuPkg/UefiCpuPkg.uni
+++ b/UefiCpuPkg/UefiCpuPkg.uni
@@ -139,3 +139,7 @@
 
 #string STR_gUefiCpuPkgTokenSpaceGuid_PcdCpuNumberOfReservedVariableMtrrs_HELP  #language en-US "Specifies the number of variable MTRRs reserved for OS use."
 
+#string STR_gUefiCpuPkgTokenSpaceGuid_PcdCpuApLoopMode_PROMPT  #language en-US "The AP wait loop state"
+
+#string STR_gUefiCpuPkgTokenSpaceGuid_PcdCpuApLoopMode_HELP  #language en-US "Specifies the AP wait loop state during POST phase."
+
-- 
2.39.2