[PATCH v4 3/7] Platform/ARM/N1Sdp: Introduce platform DXE driver

["Khasim Mohammed" <khasim.mohammed@arm.com>]

Add an initial platform DXE driver and support for ramdisk devices.

Signed-off-by: Deepak Pandey <Deepak.Pandey@arm.com>
Signed-off-by: Khasim Syed Mohammed <khasim.mohammed@arm.com>
---
 .../N1Sdp/Drivers/PlatformDxe/PlatformDxe.c   | 59 +++++++++++++++++++
 .../N1Sdp/Drivers/PlatformDxe/PlatformDxe.inf | 47 +++++++++++++++
 2 files changed, 106 insertions(+)
 create mode 100644 Platform/ARM/N1Sdp/Drivers/PlatformDxe/PlatformDxe.c
 create mode 100644 Platform/ARM/N1Sdp/Drivers/PlatformDxe/PlatformDxe.inf

diff --git a/Platform/ARM/N1Sdp/Drivers/PlatformDxe/PlatformDxe.c b/Platform/ARM/N1Sdp/Drivers/PlatformDxe/PlatformDxe.c
new file mode 100644
index 0000000000..3f975fa5ac
--- /dev/null
+++ b/Platform/ARM/N1Sdp/Drivers/PlatformDxe/PlatformDxe.c
@@ -0,0 +1,59 @@
+/** @file
+
+  Copyright (c) 2021, ARM Limited. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/DebugLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Protocol/RamDisk.h>
+
+/**
+  Entrypoint of Platform Dxe Driver
+
+  @param  ImageHandle[in]      The firmware allocated handle for the EFI image.
+  @param  SystemTable[in]      A pointer to the EFI System Table.
+
+  @retval EFI_SUCCESS          The RAM disk has been registered.
+  @retval EFI_NOT_FOUND        No RAM disk protocol instances were found.
+  @retval EFI_UNSUPPORTED      The ImageType is not supported.
+  @retval Others               Unexpected error happened.
+
+**/
+EFI_STATUS
+EFIAPI
+ArmN1SdpEntryPoint (
+  IN EFI_HANDLE         ImageHandle,
+  IN EFI_SYSTEM_TABLE   *SystemTable
+  )
+{
+  EFI_STATUS                 Status;
+  EFI_RAM_DISK_PROTOCOL      *RamDisk;
+  EFI_DEVICE_PATH_PROTOCOL   *DevicePath;
+
+  Status = EFI_UNSUPPORTED;
+  if (FeaturePcdGet (PcdRamDiskSupported)) {
+    Status = gBS->LocateProtocol (&gEfiRamDiskProtocolGuid, NULL,
+                    (VOID**) &RamDisk);
+    if (EFI_ERROR (Status)) {
+      DEBUG ((DEBUG_ERROR, "%a: Couldn't find the RAM Disk protocol - %r\n",
+                    __FUNCTION__, Status));
+      return Status;
+    }
+
+    Status = RamDisk->Register (
+               (UINTN)PcdGet32 (PcdRamDiskBase),
+               (UINTN)PcdGet32 (PcdRamDiskSize),
+               &gEfiVirtualCdGuid,
+               NULL,
+               &DevicePath
+               );
+    if (EFI_ERROR (Status)) {
+      DEBUG ((DEBUG_ERROR, "%a: Failed to register RAM Disk - %r\n",
+                    __FUNCTION__, Status));
+    }
+  }
+  return Status;
+}
diff --git a/Platform/ARM/N1Sdp/Drivers/PlatformDxe/PlatformDxe.inf b/Platform/ARM/N1Sdp/Drivers/PlatformDxe/PlatformDxe.inf
new file mode 100644
index 0000000000..d74f09b46c
--- /dev/null
+++ b/Platform/ARM/N1Sdp/Drivers/PlatformDxe/PlatformDxe.inf
@@ -0,0 +1,47 @@
+## @file
+#  Platform DXE driver for N1Sdp
+#
+#  Copyright (c) 2021, ARM Limited. All rights reserved.<BR>
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x0001001B
+  BASE_NAME                      = PlatformDxe
+  FILE_GUID                      = 116dcefb-aa53-46aa-81cd-49581684db55
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  ENTRY_POINT                    = ArmN1SdpEntryPoint
+
+[Sources.common]
+  PlatformDxe.c
+
+[Packages]
+  ArmPkg/ArmPkg.dec
+  ArmPlatformPkg/ArmPlatformPkg.dec
+  EmbeddedPkg/EmbeddedPkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  MdePkg/MdePkg.dec
+  Platform/ARM/N1Sdp/N1SdpPlatform.dec
+
+[LibraryClasses]
+  HobLib
+  UefiDriverEntryPoint
+
+[Protocols]
+  gEfiRamDiskProtocolGuid
+
+[Guids]
+  gEfiVirtualCdGuid            ## SOMETIMES_CONSUMES ## GUID
+
+[FeaturePcd]
+  gArmN1SdpTokenSpaceGuid.PcdRamDiskSupported
+
+[FixedPcd]
+  gArmN1SdpTokenSpaceGuid.PcdRamDiskBase
+  gArmN1SdpTokenSpaceGuid.PcdRamDiskSize
+
+[Depex]
+  gEfiRamDiskProtocolGuid
-- 
2.17.1