[edk2-platforms: PATCH 1/1] Platforms/RPi3: Add multiple embedded Device Tree selection

["Pete Batard" <pete@akeo.ie>]

The Raspberry Pi 3 platform currently has 2 different models, each with a
different Device Tree. Rather than embedding a single one, and requiring
users to manually provide the other, this patch ensures that we now embed
both and and serve the relevant one at runtime.

Signed-off-by: Pete Batard <pete@akeo.ie>
---
 Platform/RaspberryPi/RPi3/Drivers/FdtDxe/FdtDxe.c   | 57 ++++++++++++++++----
 Platform/RaspberryPi/RPi3/Drivers/FdtDxe/FdtDxe.inf |  3 +-
 Platform/RaspberryPi/RPi3/RPi3.dec                  |  3 +-
 Platform/RaspberryPi/RPi3/RPi3.fdf                  |  6 ++-
 4 files changed, 55 insertions(+), 14 deletions(-)

diff --git a/Platform/RaspberryPi/RPi3/Drivers/FdtDxe/FdtDxe.c b/Platform/RaspberryPi/RPi3/Drivers/FdtDxe/FdtDxe.c
index c84e5b2767e2..7c0ab75e7cb1 100644
--- a/Platform/RaspberryPi/RPi3/Drivers/FdtDxe/FdtDxe.c
+++ b/Platform/RaspberryPi/RPi3/Drivers/FdtDxe/FdtDxe.c
@@ -20,6 +20,11 @@
 
 #include <Guid/Fdt.h>
 
+CONST  EFI_GUID                         *mFdtGuid[] = {
+                                           &gRaspberryPiFdtGuid1,
+                                           &gRaspberryPiFdtGuid2,
+                                        };
+
 STATIC VOID                             *mFdtImage;
 
 STATIC RASPBERRY_PI_FIRMWARE_PROTOCOL   *mFwProtocol;
@@ -368,7 +373,9 @@ FdtDxeInitialize (
   EFI_STATUS Status;
   VOID       *FdtImage;
   UINTN      FdtSize;
+  UINTN      FdtIndex;
   INT32      Retval;
+  UINT32     BoardRevision;
   BOOLEAN    Internal;
 
   Status = gBS->LocateProtocol (&gRaspberryPiFirmwareProtocolGuid, NULL,
@@ -383,13 +390,41 @@ FdtDxeInitialize (
      * Have FDT passed via config.txt.
      */
     FdtSize = fdt_totalsize (FdtImage);
-    DEBUG ((DEBUG_INFO, "DTB passed via config.txt of 0x%lx bytes\n", FdtSize));
+    DEBUG ((DEBUG_INFO, "Device Tree passed via config.txt (0x%lx bytes)\n", FdtSize));
     Status = EFI_SUCCESS;
   } else {
+    /*
+     * Use one of the embedded FDT's.
+     */
     Internal = TRUE;
-    DEBUG ((DEBUG_INFO, "No/bad FDT at %p (%a), trying internal DTB...\n",
-      FdtImage, fdt_strerror (Retval)));
-    Status = GetSectionFromAnyFv (&gRaspberryPiFdtFileGuid, EFI_SECTION_RAW, 0,
+    DEBUG ((DEBUG_INFO, "No/Bad Device Tree found at address 0x%p (%a), "
+      "looking up internal one...\n", FdtImage, fdt_strerror (Retval)));
+    /*
+     * Query the board revision to differentiate between models.
+     */
+    Status = mFwProtocol->GetModelRevision (&BoardRevision);
+    if (EFI_ERROR (Status)) {
+      FdtIndex = 0;
+      DEBUG ((DEBUG_ERROR, "Failed to get board type: %r\n", Status));
+    } else {
+      // www.raspberrypi.org/documentation/hardware/raspberrypi/revision-codes/README.md
+      switch ((BoardRevision >> 4) & 0xFF) {
+      case 0x08:  // Raspberry 3 Model B
+        DEBUG ((DEBUG_INFO, "Using RPi3 Model B internal Device Tree\n"));
+        FdtIndex = 0;
+        break;
+      case 0x0D:  // Raspberry 3 Model B+
+        DEBUG ((DEBUG_INFO, "Using RPi3 Model B+ internal Device Tree\n"));
+        FdtIndex = 1;
+        break;
+      default:
+        DEBUG ((DEBUG_INFO, "Using default internal Device Tree\n"));
+        FdtIndex = 0;
+        break;
+      }
+    }
+    ASSERT (FdtIndex < ARRAY_SIZE (mFdtGuid));
+    Status = GetSectionFromAnyFv (mFdtGuid[FdtIndex], EFI_SECTION_RAW, 0,
                &FdtImage, &FdtSize);
     if (Status == EFI_SUCCESS) {
       if (fdt_check_header (FdtImage) != 0) {
@@ -419,27 +454,27 @@ FdtDxeInitialize (
 
   Status = SanitizePSCI ();
   if (EFI_ERROR (Status)) {
-    Print (L"Failed to sanitize PSCI (error %d)\n", Status);
+    Print (L"Failed to sanitize PSCI: %r\n", Status);
   }
 
   Status = CleanMemoryNodes ();
   if (EFI_ERROR (Status)) {
-    Print (L"Failed to clean memory nodes (error %d)\n", Status);
+    Print (L"Failed to clean memory nodes: %r\n", Status);
   }
 
   Status = CleanSimpleFramebuffer ();
   if (EFI_ERROR (Status)) {
-    Print (L"Failed to clean frame buffer (error %d)\n", Status);
+    Print (L"Failed to clean frame buffer: %r\n", Status);
   }
 
   Status = FixEthernetAliases ();
   if (EFI_ERROR (Status)) {
-    Print (L"Failed to fix ethernet aliases (error %d)\n", Status);
+    Print (L"Failed to fix ethernet aliases: %r\n", Status);
   }
 
   Status = UpdateMacAddress ();
   if (EFI_ERROR (Status)) {
-    Print (L"Failed to update MAC address (error %d)\n", Status);
+    Print (L"Failed to update MAC address: %r\n", Status);
   }
 
   if (Internal) {
@@ -448,11 +483,11 @@ FdtDxeInitialize (
      */
     Status = UpdateBootArgs ();
     if (EFI_ERROR (Status)) {
-      Print (L"Failed to update boot arguments (error %d)\n", Status);
+      Print (L"Failed to update boot arguments: %r\n", Status);
     }
   }
 
-  DEBUG ((DEBUG_INFO, "Installed FDT is at %p\n", mFdtImage));
+  DEBUG ((DEBUG_INFO, "Installed Device Tree at address 0x%p\n", mFdtImage));
   Status = gBS->InstallConfigurationTable (&gFdtTableGuid, mFdtImage);
   ASSERT_EFI_ERROR (Status);
 
diff --git a/Platform/RaspberryPi/RPi3/Drivers/FdtDxe/FdtDxe.inf b/Platform/RaspberryPi/RPi3/Drivers/FdtDxe/FdtDxe.inf
index 5b0b1a09f374..c994a2b69d78 100644
--- a/Platform/RaspberryPi/RPi3/Drivers/FdtDxe/FdtDxe.inf
+++ b/Platform/RaspberryPi/RPi3/Drivers/FdtDxe/FdtDxe.inf
@@ -35,7 +35,8 @@ [LibraryClasses]
 
 [Guids]
   gFdtTableGuid
-  gRaspberryPiFdtFileGuid
+  gRaspberryPiFdtGuid1
+  gRaspberryPiFdtGuid2
 
 [Protocols]
   gRaspberryPiFirmwareProtocolGuid              ## CONSUMES
diff --git a/Platform/RaspberryPi/RPi3/RPi3.dec b/Platform/RaspberryPi/RPi3/RPi3.dec
index 22de439fde8f..d90ea8329818 100644
--- a/Platform/RaspberryPi/RPi3/RPi3.dec
+++ b/Platform/RaspberryPi/RPi3/RPi3.dec
@@ -24,7 +24,8 @@ [Protocols]
 
 [Guids]
   gRaspberryPiTokenSpaceGuid = {0xCD7CC258, 0x31DB, 0x11E6, {0x9F, 0xD3, 0x63, 0xB0, 0xB8, 0xEE, 0xD6, 0xB5}}
-  gRaspberryPiFdtFileGuid = {0xDF5DA223, 0x1D27, 0x47C3, { 0x8D, 0x1B, 0x9A, 0x41, 0xB5, 0x5A, 0x18, 0xBC}}
+  gRaspberryPiFdtGuid1 = {0xDF5DA223, 0x1D27, 0x47C3, { 0x8D, 0x1B, 0x9A, 0x41, 0xB5, 0x5A, 0x18, 0xBC}}
+  gRaspberryPiFdtGuid2 = {0x3D523012, 0x73FE, 0x40E5, { 0x89, 0x2E, 0x1A, 0x4D, 0xF6, 0x0F, 0x3C, 0x0C}}
   gRaspberryPiEventResetGuid = {0xCD7CC258, 0x31DB, 0x11E6, {0x9F, 0xD3, 0x63, 0xB4, 0xB4, 0xE4, 0xD4, 0xB4}}
   gConfigDxeFormSetGuid = {0xCD7CC258, 0x31DB, 0x22E6, {0x9F, 0x22, 0x63, 0xB0, 0xB8, 0xEE, 0xD6, 0xB5}}
 
diff --git a/Platform/RaspberryPi/RPi3/RPi3.fdf b/Platform/RaspberryPi/RPi3/RPi3.fdf
index c62d649834c7..83753d84badc 100644
--- a/Platform/RaspberryPi/RPi3/RPi3.fdf
+++ b/Platform/RaspberryPi/RPi3/RPi3.fdf
@@ -300,11 +300,15 @@ [FV.FvMain]
   INF Platform/RaspberryPi/$(PLATFORM_NAME)/Drivers/LogoDxe/LogoDxe.inf
 
   #
-  # FDT (GUID matches gRaspberryPiFdtFileGuid in FdtDxe)
+  # Device Tree support
+  # GUIDs match gRaspberryPiFdtGuid# from FdtDxe.
   #
   FILE FREEFORM = DF5DA223-1D27-47C3-8D1B-9A41B55A18BC {
     SECTION RAW = Platform/RaspberryPi/$(PLATFORM_NAME)/DeviceTree/bcm2710-rpi-3-b.dtb
   }
+  FILE FREEFORM = 3D523012-73FE-40E5-892E-1A4DF60F3C0C {
+    SECTION RAW = Platform/RaspberryPi/$(PLATFORM_NAME)/DeviceTree/bcm2710-rpi-3-b-plus.dtb
+  }
 
 [FV.FVMAIN_COMPACT]
 FvAlignment        = 16
-- 
2.21.0.windows.1