[edk2-devel] [PATCH v2 18/45] ArmVirtPkg: Configure the MMIO regions for Arm CCA

["Sami Mujawar" <sami.mujawar@arm.com>]

The IPA space of a Realm is divided into two halves:
  - Protected IPA space and
  - Unprotected IPA space.

Software in a Realm should treat the most significant bit of an
IPA as a protection attribute.

The Unprotected IPA space is used for sharing memory and for performing
MMIO accesses with the Host.

An Unprotected IPA is an address in the upper half of a Realm's
IPA space. The most significant bit of an Unprotected IPA is 1.

The page tables for the MMIO regions must be updated to set the most
significant bit of the IPA space.

Therefore, implement ArmCcaConfigureMmio () which configures the MMIO
regions as Unprotected IPA by setting the protection attribute in the
page tables for the MMIO regions.

Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
---
 ArmVirtPkg/Library/KvmtoolVirtMemInfoLib/KvmtoolVirtMemInfoLib.c   | 39 +++++++++++++++++++-
 ArmVirtPkg/Library/KvmtoolVirtMemInfoLib/KvmtoolVirtMemInfoLib.inf |  3 +-
 2 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/ArmVirtPkg/Library/KvmtoolVirtMemInfoLib/KvmtoolVirtMemInfoLib.c b/ArmVirtPkg/Library/KvmtoolVirtMemInfoLib/KvmtoolVirtMemInfoLib.c
index 79412897f2251712fafa4a9633b44235f2d7bb9b..a4fee904a43ccb8844ceaea992698a99df2a8b3c 100644
--- a/ArmVirtPkg/Library/KvmtoolVirtMemInfoLib/KvmtoolVirtMemInfoLib.c
+++ b/ArmVirtPkg/Library/KvmtoolVirtMemInfoLib/KvmtoolVirtMemInfoLib.c
@@ -1,14 +1,16 @@
 /** @file
   Kvmtool virtual memory map library.
 
-  Copyright (c) 2018 - 2020, ARM Limited. All rights reserved.
+  Copyright (c) 2018 - 2023, Arm Limited. All rights reserved.
 
   SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
 #include <Base.h>
+#include <Library/ArmCcaLib.h>
 #include <Library/ArmLib.h>
+#include <Library/ArmMmuLib.h>
 #include <Library/BaseLib.h>
 #include <Library/BaseMemoryLib.h>
 #include <Library/DebugLib.h>
@@ -96,3 +98,38 @@ ArmVirtGetMemoryMap (
 
   *VirtualMemoryMap = VirtualMemoryTable;
 }
+
+/**
+  Configure the MMIO regions as shared with the VMM.
+
+  Set the protection attribute for the MMIO regions as Unprotected IPA.
+
+  @param[in]    IpaWidth  IPA width of the Realm.
+
+  @retval RETURN_SUCCESS            Success.
+  @retval RETURN_INVALID_PARAMETER  A parameter is invalid.
+  @retval RETURN_UNSUPPORTED        The execution context is not in a Realm.
+**/
+EFI_STATUS
+EFIAPI
+ArmCcaConfigureMmio (
+  IN UINT64  IpaWidth
+  )
+{
+  EFI_STATUS  Status;
+
+  if (!IsRealm ()) {
+    return RETURN_UNSUPPORTED;
+  }
+
+  // Set the protection attribute for the Peripheral memory.
+  // Peripheral space before DRAM
+  Status = ArmCcaSetMemoryProtectAttribute (
+             0,
+             PcdGet64 (PcdSystemMemoryBase),
+             IpaWidth,
+             TRUE
+             );
+  ASSERT_EFI_ERROR (Status);
+  return Status;
+}
diff --git a/ArmVirtPkg/Library/KvmtoolVirtMemInfoLib/KvmtoolVirtMemInfoLib.inf b/ArmVirtPkg/Library/KvmtoolVirtMemInfoLib/KvmtoolVirtMemInfoLib.inf
index a354e734ab1b7308a3e52b4e2b4885ef29592681..8e157a44dc9d11b9258d3f6182d5b169ec97ae9c 100644
--- a/ArmVirtPkg/Library/KvmtoolVirtMemInfoLib/KvmtoolVirtMemInfoLib.inf
+++ b/ArmVirtPkg/Library/KvmtoolVirtMemInfoLib/KvmtoolVirtMemInfoLib.inf
@@ -1,7 +1,7 @@
 ## @file
 #  Kvmtool virtual memory map library.
 #
-#  Copyright (c) 2018, ARM Limited. All rights reserved.
+#  Copyright (c) 2018 - 2023, Arm Limited. All rights reserved.
 #
 #  SPDX-License-Identifier: BSD-2-Clause-Patent
 #
@@ -26,6 +26,7 @@ [Packages]
   MdePkg/MdePkg.dec
 
 [LibraryClasses]
+  ArmCcaLib
   ArmLib
   BaseLib
   BaseMemoryLib
-- 
'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)'



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