[PATCH v2 06/13] Platforms/FVP: add DtPlatformDtbLoaderLib implementation

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

In preparation of switching to DtPlatformDxe to supply the device
tree image to the OS, add an implementation of DtPlatformDtbLoaderLib
that loads the correct version from an FV.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 Platforms/ARM/VExpress/Library/ArmVExpressDtPlatformDtbLoaderLib/ArmVExpressDtPlatformDtbLoaderLib.c   | 134 ++++++++++++++++++++
 Platforms/ARM/VExpress/Library/ArmVExpressDtPlatformDtbLoaderLib/ArmVExpressDtPlatformDtbLoaderLib.inf |  39 ++++++
 2 files changed, 173 insertions(+)

diff --git a/Platforms/ARM/VExpress/Library/ArmVExpressDtPlatformDtbLoaderLib/ArmVExpressDtPlatformDtbLoaderLib.c b/Platforms/ARM/VExpress/Library/ArmVExpressDtPlatformDtbLoaderLib/ArmVExpressDtPlatformDtbLoaderLib.c
new file mode 100644
index 000000000000..3a5613c83709
--- /dev/null
+++ b/Platforms/ARM/VExpress/Library/ArmVExpressDtPlatformDtbLoaderLib/ArmVExpressDtPlatformDtbLoaderLib.c
@@ -0,0 +1,134 @@
+/** @file
+*
+*  Copyright (c) 2017, Linaro, Ltd. 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 <PiDxe.h>
+
+#include <Library/ArmGicLib.h>
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/DxeServicesLib.h>
+#include <Library/IoLib.h>
+#include <Library/MemoryAllocationLib.h>
+
+#include "ArmPlatform.h"
+
+typedef enum {
+  ARM_FVP_BASE_AEMv8x4_AEMv8x4_GICV2,
+  ARM_FVP_BASE_AEMv8x4_AEMv8x4_GICV2_LEGACY,
+  ARM_FVP_BASE_AEMv8x4_AEMv8x4_GICV3,
+  ARM_FVP_FOUNDATION_GICV2,
+  ARM_FVP_FOUNDATION_GICV2_LEGACY,
+  ARM_FVP_FOUNDATION_GICV3,
+  ARM_FVP_UNKNOWN,
+} ARM_VEXPRESS_PLATFORM_ID;
+
+ARM_VEXPRESS_PLATFORM_ID
+GetPlatformId (
+  VOID
+  )
+{
+  UINT32                SysId;
+  UINT32                FvpSysId;
+  UINT32                VariantSysId;
+  ARM_GIC_ARCH_REVISION GicRevision;
+
+  SysId = MmioRead32 (ARM_VE_SYS_ID_REG);
+
+  // Remove the GIC variant to identify if we are running on the FVP Base or
+  // Foundation models
+  FvpSysId     = SysId & (ARM_FVP_SYS_ID_HBI_MASK | ARM_FVP_SYS_ID_PLAT_MASK );
+  // Extract the variant from the SysId
+  VariantSysId = SysId & ARM_FVP_SYS_ID_VARIANT_MASK;
+
+  if (FvpSysId == ARM_FVP_BASE_BOARD_SYS_ID) {
+    if (VariantSysId == ARM_FVP_GIC_VE_MMAP) {
+      // FVP Base Model with legacy GIC memory map -- no longer supported
+      return ARM_FVP_BASE_AEMv8x4_AEMv8x4_GICV2_LEGACY;
+    } else {
+      GicRevision = ArmGicGetSupportedArchRevision ();
+
+      if (GicRevision == ARM_GIC_ARCH_REVISION_2) {
+        // FVP Base Model with GICv2 support
+        return ARM_FVP_BASE_AEMv8x4_AEMv8x4_GICV2;
+      } else {
+        // FVP Base Model with GICv3 support
+        return ARM_FVP_BASE_AEMv8x4_AEMv8x4_GICV3;
+      }
+    }
+  } else if (FvpSysId == ARM_FVP_FOUNDATION_BOARD_SYS_ID) {
+    if (VariantSysId == ARM_FVP_GIC_VE_MMAP) {
+      // FVP Foundation Model with legacy GIC memory map -- no longer supported
+      return ARM_FVP_FOUNDATION_GICV2_LEGACY;
+    } else {
+      GicRevision = ArmGicGetSupportedArchRevision ();
+
+      if (GicRevision == ARM_GIC_ARCH_REVISION_2) {
+        // FVP Foundation Model with GICv2
+        return ARM_FVP_FOUNDATION_GICV2;
+      } else {
+        // FVP Foundation Model with GICv3
+        return ARM_FVP_FOUNDATION_GICV3;
+      }
+    }
+  }
+  return ARM_FVP_UNKNOWN;
+}
+
+/**
+  Return a pool allocated copy of the DTB image that is appropriate for
+  booting the current platform via DT.
+
+  @param[out]   Dtb                   Pointer to the DTB copy
+  @param[out]   DtbSize               Size of the DTB copy
+
+  @retval       EFI_SUCCESS           Operation completed successfully
+  @retval       EFI_NOT_FOUND         No suitable DTB image could be located
+  @retval       EFI_OUT_OF_RESOURCES  No pool memory available
+
+**/
+EFI_STATUS
+EFIAPI
+DtPlatformLoadDtb (
+  OUT   VOID        **Dtb,
+  OUT   UINTN       *DtbSize
+  )
+{
+  EFI_STATUS                Status;
+  VOID                      *OrigDtb;
+  VOID                      *CopyDtb;
+  UINTN                     OrigDtbSize;
+  ARM_VEXPRESS_PLATFORM_ID  PlatformId;
+
+  PlatformId = GetPlatformId ();
+  ASSERT (PlatformId < ARM_FVP_UNKNOWN);
+  if (PlatformId >= ARM_FVP_UNKNOWN) {
+    return EFI_NOT_FOUND;
+  }
+
+  Status = GetSectionFromAnyFv (&gDtPlatformDefaultDtbFileGuid,
+             EFI_SECTION_RAW, (UINTN)PlatformId, &OrigDtb, &OrigDtbSize);
+  if (EFI_ERROR (Status)) {
+    return EFI_NOT_FOUND;
+  }
+
+  CopyDtb = AllocateCopyPool (OrigDtbSize, OrigDtb);
+  if (CopyDtb == NULL) {
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  *Dtb = CopyDtb;
+  *DtbSize = OrigDtbSize;
+
+  return EFI_SUCCESS;
+}
diff --git a/Platforms/ARM/VExpress/Library/ArmVExpressDtPlatformDtbLoaderLib/ArmVExpressDtPlatformDtbLoaderLib.inf b/Platforms/ARM/VExpress/Library/ArmVExpressDtPlatformDtbLoaderLib/ArmVExpressDtPlatformDtbLoaderLib.inf
new file mode 100644
index 000000000000..5012101fe8db
--- /dev/null
+++ b/Platforms/ARM/VExpress/Library/ArmVExpressDtPlatformDtbLoaderLib/ArmVExpressDtPlatformDtbLoaderLib.inf
@@ -0,0 +1,39 @@
+/** @file
+*
+*  Copyright (c) 2017, Linaro, Ltd. 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.
+*
+**/
+
+[Defines]
+  INF_VERSION                    = 0x00010019
+  BASE_NAME                      = ArmVExpressDtPlatformDtbLoaderLib
+  FILE_GUID                      = 050d6041-1508-4ae7-a69f-250155ccb567
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = DtPlatformDtbLoaderLib|DXE_DRIVER
+
+[Sources]
+  ArmVExpressDtPlatformDtbLoaderLib.c
+
+[Packages]
+  ArmPkg/ArmPkg.dec
+  MdePkg/MdePkg.dec
+  EmbeddedPkg/EmbeddedPkg.dec
+
+[LibraryClasses]
+  ArmGicLib
+  BaseLib
+  DxeServicesLib
+  IoLib
+  MemoryAllocationLib
+
+[Guids]
+  gDtPlatformDefaultDtbFileGuid
-- 
2.9.3