[edk2-platforms][PATCH V1 2/3] Platform/Sgi: add StandaloneMM usable NorFlashPlatformLib

["Sayanta Pattanayak" <sayanta.pattanayak@arm.com>]

Add the NorFlashPlatformLib library instance that can be linked with
MM_STANDALONE modules that implement a secure variable storage. The
third instance of the NOR flash is used as the non-volatile storage.

Signed-off-by: Sayanta Pattanayak <sayanta.pattanayak@arm.com>
---
 Platform/ARM/SgiPkg/SgiPlatform.dec                                 |  1 +
 Platform/ARM/SgiPkg/Library/NorFlashLib/StandaloneMmNorFlashLib.inf | 33 ++++++++
 Platform/ARM/SgiPkg/Library/NorFlashLib/StandaloneMmNorFlashLib.c   | 82 ++++++++++++++++++++
 3 files changed, 116 insertions(+)

diff --git a/Platform/ARM/SgiPkg/SgiPlatform.dec b/Platform/ARM/SgiPkg/SgiPlatform.dec
index 3effd49592ea..af08ed153eae 100644
--- a/Platform/ARM/SgiPkg/SgiPlatform.dec
+++ b/Platform/ARM/SgiPkg/SgiPlatform.dec
@@ -54,6 +54,7 @@
 
   gArmSgiTokenSpaceGuid.PcdSmcCs0Base|0|UINT64|0x0000000C
   gArmSgiTokenSpaceGuid.PcdSmcCs1Base|0|UINT64|0x0000000D
+  gArmSgiTokenSpaceGuid.PcdSmcCs2Base|0|UINT64|0x00001000
   gArmSgiTokenSpaceGuid.PcdSysPeriphBase|0x00000000|UINT64|0x0000000E
   gArmSgiTokenSpaceGuid.PcdSysPeriphSysRegBase|0x0|UINT64|0x0000000F
 
diff --git a/Platform/ARM/SgiPkg/Library/NorFlashLib/StandaloneMmNorFlashLib.inf b/Platform/ARM/SgiPkg/Library/NorFlashLib/StandaloneMmNorFlashLib.inf
new file mode 100644
index 000000000000..96bbf1e42313
--- /dev/null
+++ b/Platform/ARM/SgiPkg/Library/NorFlashLib/StandaloneMmNorFlashLib.inf
@@ -0,0 +1,33 @@
+## @file
+#  StandaloneMM instance of NOR Flash library.
+#
+#  Copyright (c) 2021, ARM Limited. All rights reserved.
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x0001001A
+  BASE_NAME                      = NorFlashMmLib
+  FILE_GUID                      = 2ce22190-b933-4d1e-99ba-8bf1f0768255
+  MODULE_TYPE                    = MM_STANDALONE
+  VERSION_STRING                 = 1.0
+  PI_SPECIFICATION_VERSION       = 0x00010032
+  LIBRARY_CLASS                  = NorFlashPlatformLib
+
+[Sources.common]
+  StandaloneMmNorFlashLib.c
+
+[Packages]
+  ArmPlatformPkg/ArmPlatformPkg.dec
+  MdePkg/MdePkg.dec
+  Platform/ARM/SgiPkg/SgiPlatform.dec
+
+[LibraryClasses]
+  BaseLib
+  DebugLib
+  IoLib
+
+[FixedPcd]
+  gArmSgiTokenSpaceGuid.PcdSysPeriphSysRegBase
+  gArmSgiTokenSpaceGuid.PcdSmcCs2Base
diff --git a/Platform/ARM/SgiPkg/Library/NorFlashLib/StandaloneMmNorFlashLib.c b/Platform/ARM/SgiPkg/Library/NorFlashLib/StandaloneMmNorFlashLib.c
new file mode 100644
index 000000000000..3e5a5612c17e
--- /dev/null
+++ b/Platform/ARM/SgiPkg/Library/NorFlashLib/StandaloneMmNorFlashLib.c
@@ -0,0 +1,82 @@
+/** @file
+* NOR flash platform library to be used in StandaloneMM context
+*
+* This file provides platform callbacks for the NOR flash module that executes
+* in the StandaloneMM context. The third NOR flash instance of 64MB size on the
+* reference design platform is assigned to be used in the StandaloneMM context.
+*
+* Copyright (c) 2021, ARM Ltd. All rights reserved.
+*
+* SPDX-License-Identifier: BSD-2-Clause-Patent
+*
+**/
+
+#include <Library/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/NorFlashPlatformLib.h>
+#include <PiMm.h>
+#include <SgiPlatform.h>
+
+//
+// 64MB NOR flash connected to CS2 is assigned to be used in StandaloneMM
+// context.
+//
+STATIC NOR_FLASH_DESCRIPTION mNorFlashDevices[] = {
+  {
+    // NOR-Flash2 assigned for secure storage.
+    FixedPcdGet64 (PcdSmcCs2Base),
+    FixedPcdGet64 (PcdSmcCs2Base),
+    SIZE_256KB * 256,
+    SIZE_256KB,
+  },
+};
+
+/** Allow access to NOR flash
+
+  On the reference design platforms, the access to NOR flash has to be
+  explicitly permitted by writing to the FLASH_RWEN bit of the SYSPH_SYS_REG
+  register.
+
+  @retval  EFI_SUCCESS  Initialize required to access NOR flash is complete.
+
+**/
+EFI_STATUS
+NorFlashPlatformInitialization (
+  VOID
+  )
+{
+  UINT64 SysRegFlash;
+
+  SysRegFlash = FixedPcdGet64 (PcdSysPeriphSysRegBase) + SGI_SYSPH_SYS_REG_FLASH;
+  MmioOr32 (SysRegFlash, SGI_SYSPH_SYS_REG_FLASH_RWEN);
+  return EFI_SUCCESS;
+}
+
+/** Returns the list of available NOR flash devices
+
+  For the StandaloneMM execution context, return the list of available NOR
+  flash devices that are available for use.
+
+  @param[in]   NorFlashDevices  Pointer to array of NOR flash devices.
+  @param[in]   Count            Number of elements in the NOR flash devices
+                                array.
+
+  @retval  EFI_SUCCESS            Valid set of NOR flash devices is returned.
+  @retval  EFI_INVALID_PARAMETER  Pointers to NOR flash devices and/or count is
+                                  invalid.
+
+**/
+EFI_STATUS
+NorFlashPlatformGetDevices (
+  OUT NOR_FLASH_DESCRIPTION   **NorFlashDevices,
+  OUT UINT32                  *Count
+  )
+{
+  if ((NorFlashDevices == NULL) || (Count == NULL)) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  *NorFlashDevices = mNorFlashDevices;
+  *Count = ARRAY_SIZE (mNorFlashDevices);
+  return EFI_SUCCESS;
+}
-- 
2.17.1