[PATCH v4 5/5] ArmPkg/ArmMmuLib: Add MMU Library suitable for use in S-EL0.

[Sughosh Ganu <sughosh.ganu@arm.com>]

From: Achin Gupta <achin.gupta@arm.com>

The Standalone MM environment runs in S-EL0 in AArch64 on ARM Standard
Platforms. Privileged firmware e.g. ARM Trusted Firmware sets up its
architectural context including the initial translation tables for the
S-EL1/EL0 translation regime. The MM environment will still request ARM
TF to change the memory attributes of memory regions during
initialization.

The Standalone MM image is a FV that encapsulates the MM foundation
and drivers. These are PE-COFF images with data and text segments.
To initialise the MM environment, Arm Trusted Firmware has to create
translation tables with sane default attributes for the memory
occupied by the FV. This library sends SVCs to ARM Trusted Firmware
to request memory permissions change for data and text segments.

This patch adds a simple MMU library suitable for execution in S-EL0 and
requesting memory permissions change operations from Arm Trusted Firmware.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Sughosh Ganu <sughosh.ganu@arm.com>
---
 ArmPkg/ArmPkg.dec                                                                                                                                       |   1 +
 ArmVirtPkg/Library/XenArmGenericTimerVirtCounterLib/XenArmGenericTimerVirtCounterLib.inf => ArmPkg/Library/StandaloneMmMmuLib/ArmMmuStandaloneMmLib.inf |  23 +--
 ArmPkg/Include/Library/{ArmMmuLib.h => StandaloneMmMmuLib.h}                                                                                            |  38 +---
 ArmPkg/Library/StandaloneMmMmuLib/Aarch64/ArmMmuStandaloneMmLib.c                                                                                       | 185 ++++++++++++++++++++
 4 files changed, 203 insertions(+), 44 deletions(-)

diff --git a/ArmPkg/ArmPkg.dec b/ArmPkg/ArmPkg.dec
index 0db7aa9d301c..d99eb6769ff1 100644
--- a/ArmPkg/ArmPkg.dec
+++ b/ArmPkg/ArmPkg.dec
@@ -42,6 +42,7 @@ [LibraryClasses.common]
   ArmMtlLib|ArmPlatformPkg/Include/Library/ArmMtlLib.h
   ArmSvcLib|Include/Library/ArmSvcLib.h
   OpteeLib|Include/Library/OpteeLib.h
+  StandaloneMmMmuLib|Include/Library/StandaloneMmMmuLib.h
 
 [Guids.common]
   gArmTokenSpaceGuid       = { 0xBB11ECFE, 0x820F, 0x4968, { 0xBB, 0xA6, 0xF7, 0x6A, 0xFE, 0x30, 0x25, 0x96 } }
diff --git a/ArmVirtPkg/Library/XenArmGenericTimerVirtCounterLib/XenArmGenericTimerVirtCounterLib.inf b/ArmPkg/Library/StandaloneMmMmuLib/ArmMmuStandaloneMmLib.inf
similarity index 56%
copy from ArmVirtPkg/Library/XenArmGenericTimerVirtCounterLib/XenArmGenericTimerVirtCounterLib.inf
copy to ArmPkg/Library/StandaloneMmMmuLib/ArmMmuStandaloneMmLib.inf
index bd6ac8039844..d589b236033c 100644
--- a/ArmVirtPkg/Library/XenArmGenericTimerVirtCounterLib/XenArmGenericTimerVirtCounterLib.inf
+++ b/ArmPkg/Library/StandaloneMmMmuLib/ArmMmuStandaloneMmLib.inf
@@ -1,7 +1,6 @@
 #/** @file
-#  Implement ArmGenericTimerCounterLib for Xen using the virtual timer
 #
-#  Copyright (c) 2014 - 2018, Linaro Ltd. All rights reserved.<BR>
+#  Copyright (c) 2017 - 2018, ARM Limited. All rights reserved.
 #
 #  This program and the accompanying materials
 #  are licensed and made available under the terms and conditions of the BSD License
@@ -15,19 +14,23 @@
 
 [Defines]
   INF_VERSION                    = 0x0001001A
-  BASE_NAME                      = XenArmGenericTimerVirtCounterLib
-  FILE_GUID                      = e3913319-96ac-4ac0-808b-8edb8776a51c
-  MODULE_TYPE                    = BASE
+  BASE_NAME                      = ArmMmuStandaloneMmCoreLib
+  FILE_GUID                      = da8f0232-fb14-42f0-922c-63104d2c70bd
+  MODULE_TYPE                    = MM_CORE_STANDALONE
   VERSION_STRING                 = 1.0
-  LIBRARY_CLASS                  = ArmGenericTimerCounterLib
+  LIBRARY_CLASS                  = StandaloneMmMmuLib
+  PI_SPECIFICATION_VERSION       = 0x00010032
 
-[Sources]
-  XenArmGenericTimerVirtCounterLib.c
+[Sources.AARCH64]
+  Aarch64/ArmMmuStandaloneMmLib.c
 
 [Packages]
-  MdePkg/MdePkg.dec
   ArmPkg/ArmPkg.dec
+  MdePkg/MdePkg.dec
 
 [LibraryClasses]
   ArmLib
-  BaseLib
+  CacheMaintenanceLib
+  MemoryAllocationLib
+
+
diff --git a/ArmPkg/Include/Library/ArmMmuLib.h b/ArmPkg/Include/Library/StandaloneMmMmuLib.h
similarity index 55%
copy from ArmPkg/Include/Library/ArmMmuLib.h
copy to ArmPkg/Include/Library/StandaloneMmMmuLib.h
index fb7fd006417c..1f7653d00430 100644
--- a/ArmPkg/Include/Library/ArmMmuLib.h
+++ b/ArmPkg/Include/Library/StandaloneMmMmuLib.h
@@ -1,6 +1,6 @@
 /** @file
 
-  Copyright (c) 2015 - 2016, Linaro Ltd. All rights reserved.<BR>
+  Copyright (c) 2018, ARM Ltd. All rights reserved.
 
   This program and the accompanying materials
   are licensed and made available under the terms and conditions of the BSD License
@@ -12,61 +12,31 @@
 
 **/
 
-#ifndef __ARM_MMU_LIB__
-#define __ARM_MMU_LIB__
-
-#include <Uefi/UefiBaseType.h>
-
-#include <Library/ArmLib.h>
-
-EFI_STATUS
-EFIAPI
-ArmConfigureMmu (
-  IN  ARM_MEMORY_REGION_DESCRIPTOR  *MemoryTable,
-  OUT VOID                          **TranslationTableBase OPTIONAL,
-  OUT UINTN                         *TranslationTableSize  OPTIONAL
-  );
+#ifndef __STANDALONEMM_MMU_LIB__
+#define __STANDALONEMM_MMU_LIB__
 
 EFI_STATUS
-EFIAPI
 ArmSetMemoryRegionNoExec (
   IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
   IN  UINT64                    Length
   );
 
 EFI_STATUS
-EFIAPI
 ArmClearMemoryRegionNoExec (
   IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
   IN  UINT64                    Length
   );
 
 EFI_STATUS
-EFIAPI
 ArmSetMemoryRegionReadOnly (
   IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
   IN  UINT64                    Length
   );
 
 EFI_STATUS
-EFIAPI
 ArmClearMemoryRegionReadOnly (
   IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
   IN  UINT64                    Length
   );
 
-VOID
-EFIAPI
-ArmReplaceLiveTranslationEntry (
-  IN  UINT64  *Entry,
-  IN  UINT64  Value
-  );
-
-EFI_STATUS
-ArmSetMemoryAttributes (
-  IN EFI_PHYSICAL_ADDRESS      BaseAddress,
-  IN UINT64                    Length,
-  IN UINT64                    Attributes
-  );
-
-#endif
+#endif /* __STANDALONEMM_MMU_LIB__ */
diff --git a/ArmPkg/Library/StandaloneMmMmuLib/Aarch64/ArmMmuStandaloneMmLib.c b/ArmPkg/Library/StandaloneMmMmuLib/Aarch64/ArmMmuStandaloneMmLib.c
new file mode 100644
index 000000000000..d7d87b7d5d69
--- /dev/null
+++ b/ArmPkg/Library/StandaloneMmMmuLib/Aarch64/ArmMmuStandaloneMmLib.c
@@ -0,0 +1,185 @@
+/** @file
+*  File managing the MMU for ARMv8 architecture in S-EL0
+*
+*  Copyright (c) 2017 - 2018, ARM Limited. All rights reserved.
+*
+*  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 <Uefi.h>
+#include <Chipset/AArch64.h>
+#include <IndustryStandard/ArmMmSvc.h>
+
+#include <Library/ArmLib.h>
+#include <Library/ArmMmuLib.h>
+#include <Library/ArmSvcLib.h>
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+
+STATIC
+EFI_STATUS
+GetMemoryPermissions (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  OUT UINT32                    *MemoryAttributes
+  )
+{
+  ARM_SVC_ARGS  GetMemoryPermissionsSvcArgs = {0};
+
+  GetMemoryPermissionsSvcArgs.Arg0 = ARM_SVC_ID_SP_GET_MEM_ATTRIBUTES_AARCH64;
+  GetMemoryPermissionsSvcArgs.Arg1 = BaseAddress;
+  GetMemoryPermissionsSvcArgs.Arg2 = 0;
+  GetMemoryPermissionsSvcArgs.Arg3 = 0;
+
+  ArmCallSvc (&GetMemoryPermissionsSvcArgs);
+  if (GetMemoryPermissionsSvcArgs.Arg0 == ARM_SVC_SPM_RET_INVALID_PARAMS) {
+    *MemoryAttributes = 0;
+    return EFI_INVALID_PARAMETER;
+  }
+
+  *MemoryAttributes = GetMemoryPermissionsSvcArgs.Arg0;
+  return EFI_SUCCESS;
+}
+
+STATIC
+EFI_STATUS
+RequestMemoryPermissionChange (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINT64                    Length,
+  IN  UINTN                     Permissions
+  )
+{
+  EFI_STATUS    Status;
+  ARM_SVC_ARGS  ChangeMemoryPermissionsSvcArgs = {0};
+
+  ChangeMemoryPermissionsSvcArgs.Arg0 = ARM_SVC_ID_SP_SET_MEM_ATTRIBUTES_AARCH64;
+  ChangeMemoryPermissionsSvcArgs.Arg1 = BaseAddress;
+  ChangeMemoryPermissionsSvcArgs.Arg2 = EFI_SIZE_TO_PAGES(Length);
+  ChangeMemoryPermissionsSvcArgs.Arg3 = Permissions;
+
+  ArmCallSvc (&ChangeMemoryPermissionsSvcArgs);
+
+  Status = ChangeMemoryPermissionsSvcArgs.Arg0;
+
+  switch (Status) {
+  case ARM_SVC_SPM_RET_SUCCESS:
+    Status = EFI_SUCCESS;
+    break;
+
+  case ARM_SVC_SPM_RET_NOT_SUPPORTED:
+    Status = EFI_UNSUPPORTED;
+    break;
+
+  case ARM_SVC_SPM_RET_INVALID_PARAMS:
+    Status = EFI_INVALID_PARAMETER;
+    break;
+
+  case ARM_SVC_SPM_RET_DENIED:
+    Status = EFI_ACCESS_DENIED;
+    break;
+
+  case ARM_SVC_SPM_RET_NO_MEMORY:
+    Status = EFI_BAD_BUFFER_SIZE;
+    break;
+
+  default:
+    Status = EFI_ACCESS_DENIED;
+    ASSERT (0);
+  }
+
+  return Status;
+}
+
+EFI_STATUS
+ArmSetMemoryRegionNoExec (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINT64                    Length
+  )
+{
+  EFI_STATUS    Status;
+  UINT32 MemoryAttributes;
+  UINT32 CodePermission;
+
+  Status = GetMemoryPermissions (BaseAddress, &MemoryAttributes);
+  if (Status != EFI_INVALID_PARAMETER) {
+    CodePermission = SET_MEM_ATTR_CODE_PERM_XN << SET_MEM_ATTR_CODE_PERM_SHIFT;
+    return RequestMemoryPermissionChange (
+             BaseAddress,
+             Length,
+             MemoryAttributes | CodePermission
+             );
+  }
+  return EFI_INVALID_PARAMETER;
+}
+
+EFI_STATUS
+ArmClearMemoryRegionNoExec (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINT64                    Length
+  )
+{
+  EFI_STATUS    Status;
+  UINT32 MemoryAttributes;
+  UINT32 CodePermission;
+
+  Status = GetMemoryPermissions (BaseAddress, &MemoryAttributes);
+  if (Status != EFI_INVALID_PARAMETER) {
+    CodePermission = SET_MEM_ATTR_CODE_PERM_XN << SET_MEM_ATTR_CODE_PERM_SHIFT;
+    return RequestMemoryPermissionChange (
+             BaseAddress,
+             Length,
+             MemoryAttributes & ~CodePermission
+             );
+  }
+  return EFI_INVALID_PARAMETER;
+}
+
+EFI_STATUS
+ArmSetMemoryRegionReadOnly (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINT64                    Length
+  )
+{
+  EFI_STATUS    Status;
+  UINT32 MemoryAttributes;
+  UINT32 DataPermission;
+
+  Status = GetMemoryPermissions (BaseAddress, &MemoryAttributes);
+  if (Status != EFI_INVALID_PARAMETER) {
+    DataPermission = SET_MEM_ATTR_DATA_PERM_RO << SET_MEM_ATTR_DATA_PERM_SHIFT;
+    return RequestMemoryPermissionChange (
+             BaseAddress,
+             Length,
+             MemoryAttributes | DataPermission
+             );
+  }
+  return EFI_INVALID_PARAMETER;
+}
+
+EFI_STATUS
+ArmClearMemoryRegionReadOnly (
+  IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
+  IN  UINT64                    Length
+  )
+{
+  EFI_STATUS    Status;
+  UINT32 MemoryAttributes;
+  UINT32 PermissionRequest;
+
+  Status = GetMemoryPermissions (BaseAddress, &MemoryAttributes);
+  if (Status != EFI_INVALID_PARAMETER) {
+    PermissionRequest = SET_MEM_ATTR_MAKE_PERM_REQUEST (SET_MEM_ATTR_DATA_PERM_RW, MemoryAttributes);
+    return RequestMemoryPermissionChange (
+             BaseAddress,
+             Length,
+             PermissionRequest
+             );
+  }
+  return EFI_INVALID_PARAMETER;
+}
-- 
2.7.4