[PATCH 1/2] ArmPlatformPkg: PL011 Dynamic clock freq Support

[Udit Kumar <udit.kumar@nxp.com>]

Some platform support dynamic clocking, Which is controlled
by some jumper setting or hardware registers.
Result of that PCD PL011UartClkInHz needs to be updated for
frequency change.
This patch implements support for dynamic frequency for
PL011 uart.
This patch implement NULL lib for such platform where
Pcd clock frequency to PL011 can change

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Udit Kumar <udit.kumar@nxp.com>
---
 .../Include/Library/ArmPlatformClockLib.h          | 32 ++++++++++++++++++++
 .../ArmPlatformClockLib.inf                        | 33 ++++++++++++++++++++
 .../ArmPlatformClockLibNull.c                      | 35 ++++++++++++++++++++++
 3 files changed, 100 insertions(+)
 create mode 100644 ArmPlatformPkg/Include/Library/ArmPlatformClockLib.h
 create mode 100644 ArmPlatformPkg/Library/ArmPlatformClockLibNull/ArmPlatformClockLib.inf
 create mode 100644 ArmPlatformPkg/Library/ArmPlatformClockLibNull/ArmPlatformClockLibNull.c

diff --git a/ArmPlatformPkg/Include/Library/ArmPlatformClockLib.h b/ArmPlatformPkg/Include/Library/ArmPlatformClockLib.h
new file mode 100644
index 0000000..f9d1425
--- /dev/null
+++ b/ArmPlatformPkg/Include/Library/ArmPlatformClockLib.h
@@ -0,0 +1,32 @@
+/** @file
+*
+*  Copyright 2018 NXP
+*
+*  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.
+*
+**/
+
+#ifndef _ARMPLATFORMCLOCKLIB_H_
+#define _ARMPLATFORMCLOCKLIB_H_
+
+
+/**
+  Return frequency of PL011.
+
+  If this function return 0 then fixed value in Pcd will be used
+
+  @return Return frequency of PL011
+
+**/
+UINT32
+ArmPlatformGetPL011ClockFreq (
+  VOID
+  );
+
+#endif
diff --git a/ArmPlatformPkg/Library/ArmPlatformClockLibNull/ArmPlatformClockLib.inf b/ArmPlatformPkg/Library/ArmPlatformClockLibNull/ArmPlatformClockLib.inf
new file mode 100644
index 0000000..b708ad3
--- /dev/null
+++ b/ArmPlatformPkg/Library/ArmPlatformClockLibNull/ArmPlatformClockLib.inf
@@ -0,0 +1,33 @@
+#/* @file
+#  Copyright 2018 NXP
+#
+#  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.
+#
+#*/
+
+[Defines]
+  INF_VERSION                    = 0x0001000A
+  BASE_NAME                      = ArmPlatformClockLibNull
+  FILE_GUID                      = af8fef24-afbb-472a-b8b7-13101a79703c
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = ArmPlatformClockLib
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  ArmPkg/ArmPkg.dec
+  ArmPlatformPkg/ArmPlatformPkg.dec
+
+[LibraryClasses]
+  ArmLib
+  DebugLib
+
+[Sources.common]
+  ArmPlatformClockLibNull.c
diff --git a/ArmPlatformPkg/Library/ArmPlatformClockLibNull/ArmPlatformClockLibNull.c b/ArmPlatformPkg/Library/ArmPlatformClockLibNull/ArmPlatformClockLibNull.c
new file mode 100644
index 0000000..28eaa63
--- /dev/null
+++ b/ArmPlatformPkg/Library/ArmPlatformClockLibNull/ArmPlatformClockLibNull.c
@@ -0,0 +1,35 @@
+/** @file
+*
+*  Copyright 2018 NXP
+*
+*  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 <Library/ArmPlatformClockLib.h>
+
+
+
+/**
+  Return clock in for PL011 Uart IP.
+**/
+UINT32
+ArmPlatformGetPL011ClockFreq (
+  VOID
+  )
+{
+  // Implement platform specific code
+  // and return PL011 freq
+
+  // Some platform supports dynamic clocking,
+  // This function needs to be implemented on platforms which supports
+  // dynamic clocking to avoid re-building of UEFI firmware for PL011
+  // clock change
+  return 0;
+}
-- 
1.9.1