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 could still request ARM TF to change the memory attributes of memory regions during initialization.
This patch adds a simple MMU library suitable for execution in S-EL0 and requesting operations from higher exception levels. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Achin Gupta <[email protected]> Signed-off-by: Supreeth Venkatesh <[email protected]> --- ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuSecLib.c | 146 ++++++++++++++++++++++++ 1 file changed, 146 insertions(+) create mode 100644 ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuSecLib.c diff --git a/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuSecLib.c b/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuSecLib.c new file mode 100644 index 0000000000..56969e31d1 --- /dev/null +++ b/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuSecLib.c @@ -0,0 +1,146 @@ +/** @file +* File managing the MMU for ARMv8 architecture in S-EL0 +* +* Copyright (c) 2017, 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> + +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 = (Length >= EFI_PAGE_SIZE) ? \ + Length >> EFI_PAGE_SHIFT : 1; + 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 + ) +{ + return RequestMemoryPermissionChange(BaseAddress, + Length, + SET_MEM_ATTR_MAKE_PERM_REQUEST( \ + SET_MEM_ATTR_DATA_PERM_RO, \ + SET_MEM_ATTR_CODE_PERM_XN)); +} + +EFI_STATUS +ArmClearMemoryRegionNoExec ( + IN EFI_PHYSICAL_ADDRESS BaseAddress, + IN UINT64 Length + ) +{ + return RequestMemoryPermissionChange(BaseAddress, + Length, + SET_MEM_ATTR_MAKE_PERM_REQUEST( \ + SET_MEM_ATTR_DATA_PERM_RO, \ + SET_MEM_ATTR_CODE_PERM_X)); +} + +EFI_STATUS +ArmSetMemoryRegionReadOnly ( + IN EFI_PHYSICAL_ADDRESS BaseAddress, + IN UINT64 Length + ) +{ + return RequestMemoryPermissionChange(BaseAddress, + Length, + SET_MEM_ATTR_MAKE_PERM_REQUEST( \ + SET_MEM_ATTR_DATA_PERM_RO, \ + SET_MEM_ATTR_CODE_PERM_XN)); +} + +EFI_STATUS +ArmClearMemoryRegionReadOnly ( + IN EFI_PHYSICAL_ADDRESS BaseAddress, + IN UINT64 Length + ) +{ + return RequestMemoryPermissionChange(BaseAddress, + Length, + SET_MEM_ATTR_MAKE_PERM_REQUEST( \ + SET_MEM_ATTR_DATA_PERM_RW, \ + SET_MEM_ATTR_CODE_PERM_XN)); +} + +EFI_STATUS +EFIAPI +ArmConfigureMmu ( + IN ARM_MEMORY_REGION_DESCRIPTOR *MemoryTable, + OUT VOID **TranslationTableBase OPTIONAL, + OUT UINTN *TranslationTableSize OPTIONAL + ) +{ + return EFI_UNSUPPORTED; +} + +EFI_STATUS +EFIAPI +ArmMmuSecLibConstructor ( + IN EFI_HANDLE ImageHandle, + IN EFI_MM_SYSTEM_TABLE *MmSystemTable + ) +{ + return EFI_SUCCESS; +} -- 2.16.2 _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
