[PATCH 1/2] Platform/ARM/Sgi: Install a Platform ID HOB

[Chandni Cherukuri <chandni.cherukuri@arm.com>]

On SGI platforms, the trusted firmware executes prior to
the SEC phase. It supplies to the SEC phase a pointer to
a fdt, that contains platform specific information such as
part number and config number of the SGI platform. The
platform code that executes during the SEC phase creates a
PPI that allows access to other PEIMs to obtain a copy of the
fdt pointer.

Further, during the PEI phase, a Platform ID PEIM installs a
Platform ID HOB. The Platform ID HOB can be used by DXE
drivers to identify the platform it is executing on.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Chandni Cherukuri <chandni.cherukuri@arm.com>
---
 .../SgiPkg/Library/PlatformLib/AArch64/Helper.S    |  15 ++-
 .../ARM/SgiPkg/Library/PlatformLib/PlatformLib.c   |  10 ++
 .../ARM/SgiPkg/Library/PlatformLib/PlatformLib.inf |   3 +
 .../Library/SgiPlatformPeiLib/SgiPlatformPeiLib.c  | 108 +++++++++++++++++++++
 .../SgiPlatformPeiLib/SgiPlatformPeiLib.inf        |  40 ++++++++
 Platform/ARM/SgiPkg/SgiPlatform.dec                |   5 +
 6 files changed, 177 insertions(+), 4 deletions(-)
 create mode 100644 Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.c
 create mode 100644 Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.inf

diff --git a/Platform/ARM/SgiPkg/Library/PlatformLib/AArch64/Helper.S b/Platform/ARM/SgiPkg/Library/PlatformLib/AArch64/Helper.S
index dab6c77..80b93ea 100644
--- a/Platform/ARM/SgiPkg/Library/PlatformLib/AArch64/Helper.S
+++ b/Platform/ARM/SgiPkg/Library/PlatformLib/AArch64/Helper.S
@@ -22,15 +22,22 @@ GCC_ASM_EXPORT(ArmPlatformPeiBootAction)
 GCC_ASM_EXPORT(ArmPlatformGetCorePosition)
 GCC_ASM_EXPORT(ArmPlatformGetPrimaryCoreMpId)
 GCC_ASM_EXPORT(ArmPlatformIsPrimaryCore)
+GCC_ASM_EXPORT(HwConfigDtBlob)
+
+HwConfigDtBlob: .long 0
 
 //
 // First platform specific function to be called in the PEI phase
 //
-// This function is actually the first function called by the PrePi
-// or PrePeiCore modules. It allows to retrieve arguments passed to
-// the UEFI firmware through the CPU registers.
-//
+// The trusted firmware passed the hw config DT blob in x1 register.
+// Keep a copy of it in a global variable.
+//VOID
+//ArmPlatformPeiBootAction (
+//  VOID
+//  );
 ASM_PFX(ArmPlatformPeiBootAction):
+  ldr  x10, =HwConfigDtBlob
+  str  x1, [x10]
   ret
 
 //UINTN
diff --git a/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.c b/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.c
index ea3201a..54860e0 100644
--- a/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.c
+++ b/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.c
@@ -15,6 +15,10 @@
 #include <Library/ArmPlatformLib.h>
 #include <Library/BaseLib.h>
 #include <Ppi/ArmMpCoreInfo.h>
+#include <SgiPlatform.h>
+
+extern UINT64 HwConfigDtBlob;
+STATIC SGI_HW_CONFIG_INFO_PPI mHwConfigDtInfoPpi;
 
 STATIC ARM_CORE_INFO mCoreInfoTable[] = {
   {
@@ -36,6 +40,7 @@ ArmPlatformInitialize (
   IN  UINTN                     MpId
   )
 {
+  mHwConfigDtInfoPpi.HwConfigDtAddr = &HwConfigDtBlob;
   return RETURN_SUCCESS;
 }
 
@@ -59,6 +64,11 @@ EFI_PEI_PPI_DESCRIPTOR gPlatformPpiTable[] = {
     EFI_PEI_PPI_DESCRIPTOR_PPI,
     &gArmMpCoreInfoPpiGuid,
     &mMpCoreInfoPpi
+  },
+  {
+    EFI_PEI_PPI_DESCRIPTOR_PPI,
+    &gHwConfigDtInfoPpiGuid,
+    &mHwConfigDtInfoPpi
   }
 };
 
diff --git a/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.inf b/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.inf
index 42e14d5..5d4bf72 100644
--- a/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.inf
+++ b/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.inf
@@ -61,7 +61,10 @@
   gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress
 
 [Guids]
+  gArmSgiPlatformIdDescriptorGuid
   gEfiHobListGuid          ## CONSUMES  ## SystemTable
+  gFdtTableGuid
 
 [Ppis]
   gArmMpCoreInfoPpiGuid
+  gHwConfigDtInfoPpiGuid
diff --git a/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.c b/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.c
new file mode 100644
index 0000000..f6446e6
--- /dev/null
+++ b/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.c
@@ -0,0 +1,108 @@
+/** @file
+*
+*  Copyright (c) 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 <Library/DebugLib.h>
+#include <Library/HobLib.h>
+#include <Library/PeimEntryPoint.h>
+#include <Library/PeiServicesLib.h>
+#include <libfdt.h>
+#include <SgiPlatform.h>
+
+/**
+
+  This function returns the Platform ID of the platform
+
+  This functions locates the HwConfig PPI and gets the base address of HW CONFIG
+  DT from which the platform ID is obtained using FDT helper functions
+
+  @return returns the platform ID on success else returns 0 on error
+
+**/
+
+STATIC
+UINT32
+GetSgiPlatformId (
+ VOID
+)
+{
+  CONST UINT32                  *Property;
+  INT32                         Offset;
+  CONST VOID                    *HwCfgDtBlob;
+  SGI_HW_CONFIG_INFO_PPI        *HwConfigInfoPpi;
+  EFI_STATUS                    Status;
+
+  Status = PeiServicesLocatePpi (&gHwConfigDtInfoPpiGuid, 0, NULL, (VOID**)&HwConfigInfoPpi);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "PeiServicesLocatePpi failed with error %r\n", Status));
+    return 0;
+  }
+
+  HwCfgDtBlob = (VOID *)(*(HwConfigInfoPpi->HwConfigDtAddr));
+  if (fdt_check_header (HwCfgDtBlob) != 0 ) {
+    DEBUG ((DEBUG_ERROR, "Invalid DTB file %p passed as HW_CONFIG\n", HwCfgDtBlob));
+    return 0;
+  }
+
+  Offset = fdt_subnode_offset (HwCfgDtBlob, 0, "system-id");
+  if (Offset == -FDT_ERR_NOTFOUND) {
+    DEBUG ((DEBUG_ERROR, "Invalid DTB : system-id node not found\n"));
+    return 0;
+  }
+
+  Property = fdt_getprop (HwCfgDtBlob, Offset, "platform-id", NULL);
+  if (Property == NULL) {
+    DEBUG ((DEBUG_ERROR, "Platform Id is NULL\n"));
+    return 0;
+  }
+
+  return fdt32_to_cpu (*Property);
+}
+
+/**
+
+ This function creates a Platform ID HOB and assigns PlatformId as the
+ HobData
+
+ @return asserts on error and returns EFI_INVALID_PARAMETER. On success
+ returns EFI_SUCCESS
+
+**/
+EFI_STATUS
+EFIAPI
+SgiPlatformIdPeim (
+ IN       EFI_PEI_FILE_HANDLE  FileHandle,
+ IN CONST EFI_PEI_SERVICES     **PeiServices
+)
+{
+  SGI_PLATFORM_DESCRIPTOR       *HobData;
+
+  //Create platform descriptor HOB
+  HobData = (SGI_PLATFORM_DESCRIPTOR *)BuildGuidHob (&gArmSgiPlatformIdDescriptorGuid,
+            sizeof (SGI_PLATFORM_DESCRIPTOR));
+
+  //Get the platform id from the platform specific hw_config device tree
+  if (HobData != NULL) {
+    HobData->PlatformId = GetSgiPlatformId ();
+    if (HobData->PlatformId == 0) {
+      ASSERT (FALSE);
+      return EFI_INVALID_PARAMETER;
+    }
+  } else {
+    DEBUG ((DEBUG_ERROR, "Platform HoB is NULL\n"));
+    ASSERT (FALSE);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  return EFI_SUCCESS;
+}
diff --git a/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.inf b/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.inf
new file mode 100644
index 0000000..502d6ac
--- /dev/null
+++ b/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.inf
@@ -0,0 +1,40 @@
+#
+#  Copyright (c) 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.
+#
+
+[Defines]
+  INF_VERSION                    = 0x0001001A
+  BASE_NAME                      = SgiPlatformIdPeiLib
+  FILE_GUID                      = a9936f3e-6a1b-11e8-8ce0-fffe69b86863
+  MODULE_TYPE                    = PEIM
+  VERSION_STRING                 = 1.0
+  ENTRY_POINT                    = SgiPlatformIdPeim
+
+[Packages]
+  EmbeddedPkg/EmbeddedPkg.dec
+  MdePkg/MdePkg.dec
+  Platform/ARM/SgiPkg/SgiPlatform.dec
+
+[LibraryClasses]
+  FdtLib
+  PeimEntryPoint
+
+[Sources]
+  SgiPlatformPeiLib.c
+
+[Guids]
+  gArmSgiPlatformIdDescriptorGuid
+
+[Ppis]
+  gHwConfigDtInfoPpiGuid
+
+[Depex]
+  TRUE
diff --git a/Platform/ARM/SgiPkg/SgiPlatform.dec b/Platform/ARM/SgiPkg/SgiPlatform.dec
index d995937..ea9f6c5 100644
--- a/Platform/ARM/SgiPkg/SgiPlatform.dec
+++ b/Platform/ARM/SgiPkg/SgiPlatform.dec
@@ -29,9 +29,14 @@
   Include                        # Root include for the package
 
 [Guids.common]
+  # ARM Sgi Platform ID descriptor
+  gArmSgiPlatformIdDescriptorGuid = { 0xf56f152a, 0xad2a, 0x11e6, { 0xb1, 0xa7, 0x00, 0x50, 0x56, 0x3c, 0x44, 0xcc } }
   gArmSgiTokenSpaceGuid      = { 0x577d6941, 0xaea1, 0x40b4, { 0x90, 0x93, 0x2a, 0x86, 0x61, 0x72, 0x5a, 0x57 } }
   gSgi575AcpiTablesiFileGuid = { 0xc712719a, 0x0aaf, 0x438c, { 0x9c, 0xdd, 0x35, 0xab, 0x4d, 0x60, 0x20, 0x7d } }
 
 [PcdsFeatureFlag.common]
   # Set this PCD to TRUE to enable virtio support.
   gArmSgiTokenSpaceGuid.PcdVirtioSupported|TRUE|BOOLEAN|0x00000001
+
+[Ppis]
+  gHwConfigDtInfoPpiGuid     = { 0x6f606eb3, 0x9123, 0x4e15, { 0xa8, 0x9b, 0x0f, 0xac, 0x66, 0xef, 0xd0, 0x17 } }
-- 
2.7.4