ArmPkg/Application/LinuxLoader: Create a Linux Loader EFI application

There are two variants of the Linux Loader EFI application:
- the ATAG version 'LinuxAtagLoader.inf': expect to start an ATAG 'zImage'
in the same directory as the EFI application
- the FDT version 'LinuxFdtLoader.inf': load the FDT blob 'platform.dtb'
and the FDT 'zImage' from the same directory as the EFI application.

When these applications are started without any argument, a menu appears
to the user to create/update a boot entry.



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12410 6f19259b-4bc3-4df7-8a09-765794883524

6 files changed, 692 insertions, 0 deletions

diff --git a/ArmPkg/Application/LinuxLoader/LinuxAtagLoader.c b/ArmPkg/Application/LinuxLoader/LinuxAtagLoader.c
new file mode 100644
index 0000000000..50a4b474cf
--- /dev/null
+++ b/ArmPkg/Application/LinuxLoader/LinuxAtagLoader.c
@@ -0,0 +1,103 @@
+/** @file

+*

+*  Copyright (c) 2011, 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 "LinuxInternal.h"

+

+#include <Library/PrintLib.h>

+#include <Library/UefiApplicationEntryPoint.h>

+

+/**

+  The user Entry Point for Application. The user code starts with this function

+  as the real entry point for the application.

+

+  @param[in] ImageHandle    The firmware allocated handle for the EFI image.

+  @param[in] SystemTable    A pointer to the EFI System Table.

+

+  @retval EFI_SUCCESS       The entry point is executed successfully.

+  @retval other             Some error occurs when executing this entry point.

+

+**/

+EFI_STATUS

+EFIAPI

+UefiMain (

+  IN EFI_HANDLE        ImageHandle,

+  IN EFI_SYSTEM_TABLE  *SystemTable

+  )

+{

+  EFI_STATUS                   Status;

+  EFI_LOADED_IMAGE_PROTOCOL   *LoadedImage;

+  LINUX_LOADER_OPTIONAL_DATA*  LinuxOptionalData;

+  EFI_DEVICE_PATH*             DevicePathKernel;

+  EFI_DEVICE_PATH*             InitrdDevicePath;

+  CHAR16*                      OptionalDataInitrd;

+  CHAR8*                       OptionalDataArguments;

+  CHAR16*                      Initrd;

+

+  Status = gBS->HandleProtocol (ImageHandle, &gEfiLoadedImageProtocolGuid, (VOID **)&LoadedImage);

+  ASSERT_EFI_ERROR (Status);

+

+  if (LoadedImage->LoadOptionsSize == 0) {

+    Status = LinuxLoaderConfig (LoadedImage);

+  } else {

+    // Ensure the signature is correct

+    LinuxOptionalData = (LINUX_LOADER_OPTIONAL_DATA*)LoadedImage->LoadOptions;

+    if (LinuxOptionalData->Signature != LINUX_LOADER_SIGNATURE) {

+      return EFI_UNSUPPORTED;

+    }

+

+    // Generate the File Path Node for the Linux Kernel

+    DevicePathKernel = FileDevicePath (LoadedImage->DeviceHandle, LINUX_KERNEL_NAME);

+

+    if (LinuxOptionalData->CmdLineLength > 0) {

+      OptionalDataArguments = (CHAR8*)LinuxOptionalData + sizeof(LINUX_LOADER_OPTIONAL_DATA);

+    } else {

+      OptionalDataArguments = NULL;

+    }

+

+    if (LinuxOptionalData->InitrdPathListLength > 0) {

+      if (OptionalDataArguments != NULL) {

+        OptionalDataInitrd = (CHAR16*)(OptionalDataArguments + LinuxOptionalData->CmdLineLength);

+      } else {

+        OptionalDataInitrd = (CHAR16*)LinuxOptionalData + sizeof(LINUX_LOADER_OPTIONAL_DATA);

+      }

+

+      // If pointer not aligned

+      if ((UINTN)OptionalDataInitrd & 0x1) {

+        Initrd = (CHAR16*)AllocateCopyPool (LinuxOptionalData->InitrdPathListLength, OptionalDataInitrd);

+      } else {

+        Initrd = OptionalDataInitrd;

+      }

+

+      InitrdDevicePath = FileDevicePath (LoadedImage->DeviceHandle, Initrd);

+    } else {

+      OptionalDataInitrd = NULL;

+      InitrdDevicePath   = NULL;

+      Initrd             = NULL;

+    }

+

+    // Load and Start the Linux Kernel (we should never return)

+    Status = BdsBootLinuxAtag (DevicePathKernel, InitrdDevicePath, OptionalDataArguments);

+

+    if ((UINTN)OptionalDataInitrd & 0x1) {

+      FreePool (Initrd);

+    }

+

+    FreePool (DevicePathKernel);

+    if (InitrdDevicePath) {

+      FreePool (InitrdDevicePath);

+    }

+  }

+

+  return Status;

+}

diff --git a/ArmPkg/Application/LinuxLoader/LinuxAtagLoader.inf b/ArmPkg/Application/LinuxLoader/LinuxAtagLoader.inf
new file mode 100644
index 0000000000..d3edb533b9
--- /dev/null
+++ b/ArmPkg/Application/LinuxLoader/LinuxAtagLoader.inf
@@ -0,0 +1,40 @@
+#/* @file

+#  Copyright (c) 2011, 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                    = 0x00010006

+  BASE_NAME                      = LinuxAtagLoader

+  FILE_GUID                      = a912f198-7f0e-4803-b908-b757b806ec83

+  MODULE_TYPE                    = UEFI_APPLICATION

+  VERSION_STRING                 = 0.1

+  ENTRY_POINT                    = UefiMain

+

+[Sources]

+  LinuxAtagLoader.c

+  LinuxConfig.c

+

+[Packages]

+  ArmPkg/ArmPkg.dec

+  MdePkg/MdePkg.dec

+

+[LibraryClasses]

+  BdsLib

+  DxeServicesTableLib

+  UefiLib

+  UefiApplicationEntryPoint

+

+[Protocols]

+  gEfiLoadedImageProtocolGuid

+  

+  #TODO: RemoveMe

+  gEfiDevicePathToTextProtocolGuid

diff --git a/ArmPkg/Application/LinuxLoader/LinuxConfig.c b/ArmPkg/Application/LinuxLoader/LinuxConfig.c
new file mode 100644
index 0000000000..88b8500725
--- /dev/null
+++ b/ArmPkg/Application/LinuxLoader/LinuxConfig.c
@@ -0,0 +1,355 @@
+/** @file
+*
+*  Copyright (c) 2011, 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 "LinuxInternal.h"
+
+//TODO: RemoveMe
+#include <Protocol/DevicePathToText.h>
+
+#define DEFAULT_BOOT_ENTRY_DESCRIPTION  L"Linux"
+#define MAX_STR_INPUT                   300
+#define MAX_ASCII_INPUT                 300
+
+typedef enum {
+  LINUX_LOADER_NEW = 1,
+  LINUX_LOADER_UPDATE
+} LINUX_LOADER_ACTION;
+
+STATIC
+EFI_STATUS
+EditHIInputStr (
+  IN OUT CHAR16  *CmdLine,
+  IN     UINTN   MaxCmdLine
+  )
+{
+  UINTN           CmdLineIndex;
+  UINTN           WaitIndex;
+  CHAR8           Char;
+  EFI_INPUT_KEY   Key;
+  EFI_STATUS      Status;
+
+  Print (CmdLine);
+
+  for (CmdLineIndex = StrLen (CmdLine); CmdLineIndex < MaxCmdLine; ) {
+    Status = gBS->WaitForEvent (1, &gST->ConIn->WaitForKey, &WaitIndex);
+    ASSERT_EFI_ERROR (Status);
+
+    Status = gST->ConIn->ReadKeyStroke (gST->ConIn, &Key);
+    ASSERT_EFI_ERROR (Status);
+
+    // Unicode character is valid when Scancode is NUll
+    if (Key.ScanCode == SCAN_NULL) {
+      // Scan code is NUll, hence read Unicode character
+      Char = (CHAR8)Key.UnicodeChar;
+    } else {
+      Char = CHAR_NULL;
+    }
+
+    if ((Char == CHAR_LINEFEED) || (Char == CHAR_CARRIAGE_RETURN) || (Char == 0x7f)) {
+      CmdLine[CmdLineIndex] = '\0';
+      Print (L"\n\r");
+
+      return EFI_SUCCESS;
+    } else if ((Key.UnicodeChar == L'\b') || (Key.ScanCode == SCAN_LEFT) || (Key.ScanCode == SCAN_DELETE)){
+      if (CmdLineIndex != 0) {
+        CmdLineIndex--;
+        Print (L"\b \b");
+      }
+    } else if ((Key.ScanCode == SCAN_ESC) || (Char == 0x1B) || (Char == 0x0)) {
+      return EFI_INVALID_PARAMETER;
+    } else {
+      CmdLine[CmdLineIndex++] = Key.UnicodeChar;
+      Print (L"%c", Key.UnicodeChar);
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+STATIC
+EFI_STATUS
+EditHIInputAscii (
+  IN OUT CHAR8   *CmdLine,
+  IN     UINTN   MaxCmdLine
+  )
+{
+  CHAR16*     Str;
+  EFI_STATUS  Status;
+
+  Str = (CHAR16*)AllocatePool (MaxCmdLine * sizeof(CHAR16));
+  AsciiStrToUnicodeStr (CmdLine, Str);
+
+  Status = EditHIInputStr (Str, MaxCmdLine);
+
+  UnicodeStrToAsciiStr (Str, CmdLine);
+  FreePool (Str);
+
+  return Status;
+}
+
+STATIC
+EFI_STATUS
+GetHIInputInteger (
+  OUT UINTN   *Integer
+  )
+{
+  CHAR16      CmdLine[255];
+  EFI_STATUS  Status;
+
+  CmdLine[0] = '\0';
+  Status = EditHIInputStr (CmdLine, 255);
+  if (!EFI_ERROR(Status)) {
+    *Integer = StrDecimalToUintn (CmdLine);
+  }
+
+  return Status;
+}
+
+#if 0
+EFI_STATUS
+GenerateDeviceDescriptionName (
+  IN  EFI_HANDLE  Handle,
+  IN OUT CHAR16*  Description
+  )
+{
+  EFI_STATUS                        Status;
+  EFI_COMPONENT_NAME_PROTOCOL*      ComponentName2Protocol;
+  EFI_DEVICE_PATH_TO_TEXT_PROTOCOL* DevicePathToTextProtocol;
+  EFI_DEVICE_PATH_PROTOCOL*         DevicePathProtocol;
+  CHAR16*                           DriverName;
+  CHAR16*                           DevicePathTxt;
+  EFI_DEVICE_PATH*                  DevicePathNode;
+
+  ComponentName2Protocol = NULL;
+  Status = gBS->HandleProtocol (Handle, &gEfiComponentName2ProtocolGuid, (VOID **)&ComponentName2Protocol);
+  if (!EFI_ERROR(Status)) {
+    //TODO: Fixme. we must find the best langague
+    Status = ComponentName2Protocol->GetDriverName (ComponentName2Protocol,"en",&DriverName);
+    if (!EFI_ERROR(Status)) {
+      StrnCpy (Description,DriverName,BOOT_DEVICE_DESCRIPTION_MAX);
+    }
+  }
+
+  if (EFI_ERROR(Status)) {
+    // Use the lastest non null entry of the Device path as a description
+    Status = gBS->HandleProtocol (Handle, &gEfiDevicePathProtocolGuid, (VOID **)&DevicePathProtocol);
+    if (EFI_ERROR(Status)) {
+      return Status;
+    }
+
+    // Convert the last non end-type Device Path Node in text for the description
+    DevicePathNode = GetLastDevicePathNode (DevicePathProtocol);
+    Status = gBS->LocateProtocol (&gEfiDevicePathToTextProtocolGuid, NULL, (VOID **)&DevicePathToTextProtocol);
+    ASSERT_EFI_ERROR(Status);
+    DevicePathTxt = DevicePathToTextProtocol->ConvertDevicePathToText(DevicePathNode,TRUE,TRUE);
+    StrnCpy (Description, DevicePathTxt, BOOT_DEVICE_DESCRIPTION_MAX);
+    FreePool (DevicePathTxt);
+  }
+
+  return EFI_SUCCESS;
+}
+#endif
+
+EFI_STATUS
+LinuxLoaderConfig (
+  IN EFI_LOADED_IMAGE_PROTOCOL   *LoadedImage
+  )
+{
+  EFI_STATUS                   Status;
+  LINUX_LOADER_ACTION          Choice;
+  UINTN                        BootOrderSize;
+  UINT16*                      BootOrder;
+  UINTN                        BootOrderCount;
+  UINTN                        Index;
+  CHAR16                       Description[MAX_ASCII_INPUT];
+  CHAR8                        CmdLine[MAX_ASCII_INPUT];
+  CHAR16                       Initrd[MAX_STR_INPUT];
+  UINT16                       InitrdPathListLength;
+  UINT16                       CmdLineLength;
+  BDS_LOAD_OPTION*             BdsLoadOption;
+  BDS_LOAD_OPTION**            SupportedBdsLoadOptions;
+  UINTN                        SupportedBdsLoadOptionCount;
+  LINUX_LOADER_OPTIONAL_DATA*  LinuxOptionalData;
+  EFI_DEVICE_PATH*             DevicePathRoot;
+
+  SupportedBdsLoadOptions = NULL;
+  SupportedBdsLoadOptionCount = 0;
+
+  do {
+    Print (L"[%d] Create new Linux Boot Entry\n",LINUX_LOADER_NEW);
+    Print (L"[%d] Update Linux Boot Entry\n",LINUX_LOADER_UPDATE);
+
+    Print (L"Option: ");
+    Status = GetHIInputInteger (&Choice);
+    if (Status == EFI_INVALID_PARAMETER) {
+      Print (L"\n");
+      return Status;
+    } else if ((Choice != LINUX_LOADER_NEW) && (Choice != LINUX_LOADER_UPDATE)) {
+      Print (L"Error: the option should be either '%d' or '%d'\n",LINUX_LOADER_NEW,LINUX_LOADER_UPDATE);
+      Status = EFI_INVALID_PARAMETER;
+    }
+  } while (EFI_ERROR(Status));
+
+  if (Choice == LINUX_LOADER_UPDATE) {
+    // If no compatible entry then we just create a new entry
+    Choice = LINUX_LOADER_NEW;
+
+    // Scan the OptionalData of every entry for the correct signature
+    Status = GetEnvironmentVariable (L"BootOrder", NULL, &BootOrderSize, (VOID**)&BootOrder);
+    if (!EFI_ERROR(Status)) {
+      BootOrderCount = BootOrderSize / sizeof(UINT16);
+
+      // Allocate an array to handle maximum number of supported Boot Entry
+      SupportedBdsLoadOptions = (BDS_LOAD_OPTION**)AllocatePool(sizeof(BDS_LOAD_OPTION*) * BootOrderCount);
+
+      SupportedBdsLoadOptionCount = 0;
+
+      // Check if the signature is present in the list of the current Boot entries
+      for (Index = 0; Index < BootOrderCount; Index++) {
+        Status = BootOptionFromLoadOptionIndex (BootOrder[Index], &BdsLoadOption);
+        if (!EFI_ERROR(Status)) {
+          if ((BdsLoadOption->OptionalDataSize >= sizeof(UINT32)) &&
+              (*(UINT32*)BdsLoadOption->OptionalData == LINUX_LOADER_SIGNATURE)) {
+            SupportedBdsLoadOptions[SupportedBdsLoadOptionCount++] = BdsLoadOption;
+            Choice = LINUX_LOADER_UPDATE;
+          }
+        }
+      }
+    }
+  }
+
+  if (Choice == LINUX_LOADER_NEW) {
+    Description[0] = '\0';
+    CmdLine[0]     = '\0';
+    Initrd[0]      = '\0';
+
+    BdsLoadOption = (BDS_LOAD_OPTION*)AllocateZeroPool (sizeof(BDS_LOAD_OPTION));
+
+    DEBUG_CODE_BEGIN();
+      CHAR16*                           DevicePathTxt;
+      EFI_DEVICE_PATH_TO_TEXT_PROTOCOL* DevicePathToTextProtocol;
+
+      Status = gBS->LocateProtocol (&gEfiDevicePathToTextProtocolGuid, NULL, (VOID **)&DevicePathToTextProtocol);
+      ASSERT_EFI_ERROR(Status);
+      DevicePathTxt = DevicePathToTextProtocol->ConvertDevicePathToText (LoadedImage->FilePath, TRUE, TRUE);
+
+      Print(L"EFI OS Loader: %s\n",DevicePathTxt);
+
+      FreePool(DevicePathTxt);
+    DEBUG_CODE_END();
+
+    //
+    // Fill the known fields of BdsLoadOption
+    //
+
+    BdsLoadOption->Attributes = LOAD_OPTION_ACTIVE | LOAD_OPTION_CATEGORY_BOOT;
+
+    // Get the full Device Path for this file
+    Status = gBS->HandleProtocol (LoadedImage->DeviceHandle, &gEfiDevicePathProtocolGuid, (VOID **)&DevicePathRoot);
+    ASSERT_EFI_ERROR(Status);
+
+    BdsLoadOption->FilePathList = AppendDevicePath (DevicePathRoot, LoadedImage->FilePath);
+    BdsLoadOption->FilePathListLength = GetDevicePathSize (BdsLoadOption->FilePathList);
+  } else {
+    if (SupportedBdsLoadOptionCount > 1) {
+      for (Index = 0; Index < SupportedBdsLoadOptionCount; Index++) {
+        Print (L"[%d] %s\n",Index + 1,SupportedBdsLoadOptions[Index]->Description);
+      }
+
+      do {
+        Print (L"Update Boot Entry: ");
+        Status = GetHIInputInteger (&Choice);
+        if (Status == EFI_INVALID_PARAMETER) {
+          Print (L"\n");
+          return Status;
+        } else if ((Choice < 1) && (Choice > SupportedBdsLoadOptionCount)) {
+          Print (L"Choose entry from 1 to %d\n",SupportedBdsLoadOptionCount);
+          Status = EFI_INVALID_PARAMETER;
+        }
+      } while (EFI_ERROR(Status));
+      BdsLoadOption = SupportedBdsLoadOptions[Choice-1];
+    }
+    StrnCpy (Description, BdsLoadOption->Description, MAX_STR_INPUT);
+
+    LinuxOptionalData = (LINUX_LOADER_OPTIONAL_DATA*)BdsLoadOption->OptionalData;
+    if (LinuxOptionalData->CmdLineLength > 0) {
+      CopyMem (CmdLine, (CHAR8*)LinuxOptionalData + sizeof(LINUX_LOADER_OPTIONAL_DATA), LinuxOptionalData->CmdLineLength);
+    } else {
+      CmdLine[0] = '\0';
+    }
+
+    if (LinuxOptionalData->InitrdPathListLength > 0) {
+      CopyMem (Initrd, (CHAR8*)LinuxOptionalData + sizeof(LINUX_LOADER_OPTIONAL_DATA) + LinuxOptionalData->CmdLineLength, LinuxOptionalData->InitrdPathListLength);
+    } else {
+      Initrd[0] = L'\0';
+    }
+    DEBUG((EFI_D_ERROR,"L\n"));
+  }
+
+  // Description
+  Print (L"Description: ");
+  Status = EditHIInputStr (Description, MAX_STR_INPUT);
+  if (EFI_ERROR(Status)) {
+    return Status;
+  }
+  if (StrLen (Description) == 0) {
+    StrnCpy (Description, DEFAULT_BOOT_ENTRY_DESCRIPTION, MAX_STR_INPUT);
+  }
+  BdsLoadOption->Description = Description;
+
+  // CmdLine
+  Print (L"Command Line: ");
+  Status = EditHIInputAscii (CmdLine, MAX_ASCII_INPUT);
+  if (EFI_ERROR(Status)) {
+    return Status;
+  }
+
+  // Initrd
+  Print (L"Initrd name: ");
+  Status = EditHIInputStr (Initrd, MAX_STR_INPUT);
+  if (EFI_ERROR(Status)) {
+    return Status;
+  }
+
+  CmdLineLength = AsciiStrLen (CmdLine);
+  if (CmdLineLength > 0) {
+    CmdLineLength += sizeof(CHAR8);
+  }
+
+  InitrdPathListLength = StrLen (Initrd) * sizeof(CHAR16);
+  if (InitrdPathListLength > 0) {
+    InitrdPathListLength += sizeof(CHAR16);
+  }
+
+  BdsLoadOption->OptionalDataSize = sizeof(LINUX_LOADER_OPTIONAL_DATA) + CmdLineLength + InitrdPathListLength;
+
+  LinuxOptionalData = (LINUX_LOADER_OPTIONAL_DATA*)AllocatePool (BdsLoadOption->OptionalDataSize);
+  BdsLoadOption->OptionalData = LinuxOptionalData;
+
+  LinuxOptionalData->Signature = LINUX_LOADER_SIGNATURE;
+  LinuxOptionalData->CmdLineLength = CmdLineLength;
+  LinuxOptionalData->InitrdPathListLength = InitrdPathListLength;
+
+  if (CmdLineLength > 0) {
+    CopyMem (LinuxOptionalData + 1, CmdLine, CmdLineLength);
+  }
+  if (InitrdPathListLength > 0) {
+    CopyMem ((UINT8*)(LinuxOptionalData + 1) + CmdLineLength, Initrd, InitrdPathListLength);
+  }
+
+  // Create or Update the boot entry
+  Status = BootOptionToLoadOptionVariable (BdsLoadOption);
+
+  return Status;
+}
diff --git a/ArmPkg/Application/LinuxLoader/LinuxFdtLoader.c b/ArmPkg/Application/LinuxLoader/LinuxFdtLoader.c
new file mode 100644
index 0000000000..2e222de51b
--- /dev/null
+++ b/ArmPkg/Application/LinuxLoader/LinuxFdtLoader.c
@@ -0,0 +1,105 @@
+/** @file

+*

+*  Copyright (c) 2011, 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 "LinuxInternal.h"

+

+#include <Library/PrintLib.h>

+#include <Library/UefiApplicationEntryPoint.h>

+

+/**

+  The user Entry Point for Application. The user code starts with this function

+  as the real entry point for the application.

+

+  @param[in] ImageHandle    The firmware allocated handle for the EFI image.

+  @param[in] SystemTable    A pointer to the EFI System Table.

+

+  @retval EFI_SUCCESS       The entry point is executed successfully.

+  @retval other             Some error occurs when executing this entry point.

+

+**/

+EFI_STATUS

+EFIAPI

+UefiMain (

+  IN EFI_HANDLE        ImageHandle,

+  IN EFI_SYSTEM_TABLE  *SystemTable

+  )

+{

+  EFI_STATUS                   Status;

+  EFI_LOADED_IMAGE_PROTOCOL   *LoadedImage;

+  LINUX_LOADER_OPTIONAL_DATA*  LinuxOptionalData;

+  EFI_DEVICE_PATH*             DevicePathKernel;

+  EFI_DEVICE_PATH*             DevicePathFdt;

+  EFI_DEVICE_PATH*             InitrdDevicePath;

+  CHAR16*                      OptionalDataInitrd;

+  CHAR8*                       OptionalDataArguments;

+  CHAR16*                      Initrd;

+

+  Status = gBS->HandleProtocol (ImageHandle, &gEfiLoadedImageProtocolGuid, (VOID **)&LoadedImage);

+  ASSERT_EFI_ERROR (Status);

+

+  if (LoadedImage->LoadOptionsSize == 0) {

+    Status = LinuxLoaderConfig (LoadedImage);

+  } else {

+    // Ensure the signature is correct

+    LinuxOptionalData = (LINUX_LOADER_OPTIONAL_DATA*)LoadedImage->LoadOptions;

+    if (LinuxOptionalData->Signature != LINUX_LOADER_SIGNATURE) {

+      return EFI_UNSUPPORTED;

+    }

+

+    // Generate the File Path Node for the Linux Kernel & Device Tree blobl

+    DevicePathKernel = FileDevicePath (LoadedImage->DeviceHandle, LINUX_KERNEL_NAME);

+    DevicePathFdt    = FileDevicePath (LoadedImage->DeviceHandle, FDT_NAME);

+

+    if (LinuxOptionalData->CmdLineLength > 0) {

+      OptionalDataArguments = (CHAR8*)LinuxOptionalData + sizeof(LINUX_LOADER_OPTIONAL_DATA);

+    } else {

+      OptionalDataArguments = NULL;

+    }

+

+    if (LinuxOptionalData->InitrdPathListLength > 0) {

+      if (OptionalDataArguments != NULL) {

+        OptionalDataInitrd = (CHAR16*)(OptionalDataArguments + LinuxOptionalData->CmdLineLength);

+      } else {

+        OptionalDataInitrd = (CHAR16*)LinuxOptionalData + sizeof(LINUX_LOADER_OPTIONAL_DATA);

+      }

+

+      // If pointer not aligned

+      if ((UINTN)OptionalDataInitrd & 0x1) {

+        Initrd = (CHAR16*)AllocateCopyPool (LinuxOptionalData->InitrdPathListLength, OptionalDataInitrd);

+      } else {

+        Initrd = OptionalDataInitrd;

+      }

+

+      InitrdDevicePath = FileDevicePath (LoadedImage->DeviceHandle, Initrd);

+    } else {

+      OptionalDataInitrd = NULL;

+      InitrdDevicePath   = NULL;

+      Initrd             = NULL;

+    }

+

+    // Load and Start the Linux Kernel (we should never return)

+    Status = BdsBootLinuxFdt (DevicePathKernel, InitrdDevicePath, OptionalDataArguments, DevicePathFdt);

+

+    if ((UINTN)OptionalDataInitrd & 0x1) {

+      FreePool (Initrd);

+    }

+

+    FreePool (DevicePathKernel);

+    if (InitrdDevicePath) {

+      FreePool (InitrdDevicePath);

+    }

+  }

+

+  return Status;

+}

diff --git a/ArmPkg/Application/LinuxLoader/LinuxFdtLoader.inf b/ArmPkg/Application/LinuxLoader/LinuxFdtLoader.inf
new file mode 100644
index 0000000000..76773af76b
--- /dev/null
+++ b/ArmPkg/Application/LinuxLoader/LinuxFdtLoader.inf
@@ -0,0 +1,40 @@
+#/* @file

+#  Copyright (c) 2011, 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                    = 0x00010006

+  BASE_NAME                      = LinuxFdtLoader

+  FILE_GUID                      = f536d559-459f-48fa-8bbc-43b554ecae8d

+  MODULE_TYPE                    = UEFI_APPLICATION

+  VERSION_STRING                 = 0.1

+  ENTRY_POINT                    = UefiMain

+

+[Sources]

+  LinuxFdtLoader.c

+  LinuxConfig.c

+

+[Packages]

+  ArmPkg/ArmPkg.dec

+  MdePkg/MdePkg.dec

+

+[LibraryClasses]

+  BdsLib

+  DxeServicesTableLib

+  UefiLib

+  UefiApplicationEntryPoint

+

+[Protocols]

+  gEfiLoadedImageProtocolGuid

+  

+  #TODO: RemoveMe

+  gEfiDevicePathToTextProtocolGuid

diff --git a/ArmPkg/Application/LinuxLoader/LinuxInternal.h b/ArmPkg/Application/LinuxLoader/LinuxInternal.h
new file mode 100644
index 0000000000..e486273520
--- /dev/null
+++ b/ArmPkg/Application/LinuxLoader/LinuxInternal.h
@@ -0,0 +1,49 @@
+/** @file
+*
+*  Copyright (c) 2011, 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.
+*
+**/
+
+#ifndef __LOADER_INTERNAL_H
+#define __LOADER_INTERNAL_H
+
+#include <Uefi.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/BdsLib.h>
+#include <Library/DebugLib.h>
+#include <Library/DevicePathLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+#include <Protocol/LoadedImage.h>
+
+#define LINUX_KERNEL_NAME               L"zImage"
+#define FDT_NAME                        L"platform.dtb"
+
+#define LINUX_LOADER_SIGNATURE    SIGNATURE_32('l', 'i', 'l', 'o')
+
+typedef struct {
+  UINT32                        Signature;
+  UINT16                        CmdLineLength;
+  UINT16                        InitrdPathListLength;
+
+  // These following fields have variable length:
+  //CHAR8*                      CmdLine;
+  //CHAR16*                     Initrd;
+} LINUX_LOADER_OPTIONAL_DATA;
+
+EFI_STATUS
+LinuxLoaderConfig (
+  IN EFI_LOADED_IMAGE_PROTOCOL   *LoadedImage
+  );
+
+#endif