ArmVirtPkg/XenioFdtDxe/XenioFdtDxe.c

   1 /** @file
   2 *  Xenio FDT client protocol driver for xen,xen DT node
   3 *
   4 *  Copyright (c) 2016, Linaro Ltd. All rights reserved.<BR>
   5 *
   6 *  This program and the accompanying materials are
   7 *  licensed and made available under the terms and conditions of the BSD License
   8 *  which accompanies this distribution.  The full text of the license may be found at
   9 *  http://opensource.org/licenses/bsd-license.php
  10 *
  11 *  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12 *  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13 *
  14 **/
  15
  16 #include <Library/BaseLib.h>
  17 #include <Library/DebugLib.h>
  18 #include <Library/UefiDriverEntryPoint.h>
  19 #include <Library/UefiBootServicesTableLib.h>
  20 #include <Library/XenIoMmioLib.h>
  21
  22 #include <Protocol/FdtClient.h>
  23
  24 EFI_STATUS
  25 EFIAPI
  26 InitializeXenioFdtDxe (
  27   IN EFI_HANDLE           ImageHandle,
  28   IN EFI_SYSTEM_TABLE     *SystemTable
  29   )
  30 {
  31   EFI_STATUS            Status;
  32   FDT_CLIENT_PROTOCOL   *FdtClient;
  33   CONST UINT64          *Reg;
  34   UINT32                RegSize;
  35   UINTN                 AddressCells, SizeCells;
  36   EFI_HANDLE            Handle;
  37   UINT64                RegBase;
  38
  39   Status = gBS->LocateProtocol (&gFdtClientProtocolGuid, NULL,
  40                   (VOID **)&FdtClient);
  41   ASSERT_EFI_ERROR (Status);
  42
  43   Status = FdtClient->FindCompatibleNodeReg (FdtClient, "xen,xen",
  44                         (CONST VOID **)&Reg, &AddressCells, &SizeCells,
  45                         &RegSize);
  46   if (EFI_ERROR (Status)) {
  47     DEBUG ((EFI_D_WARN, "%a: No 'xen,xen' compatible DT node found\n",
  48       __FUNCTION__));
  49     return EFI_UNSUPPORTED;
  50   }
  51
  52   ASSERT (AddressCells == 2);
  53   ASSERT (SizeCells == 2);
  54   ASSERT (RegSize == 2 * sizeof (UINT64));
  55
  56   //
  57   // Retrieve the reg base from this node and wire it up to the
  58   // MMIO flavor of the XenBus root device I/O protocol
  59   //
  60   RegBase = SwapBytes64 (Reg[0]);
  61   Handle = NULL;
  62   Status = XenIoMmioInstall (&Handle, RegBase);
  63   if (EFI_ERROR (Status)) {
  64     DEBUG ((EFI_D_ERROR, "%a: XenIoMmioInstall () failed on a new handle "
  65       "(Status == %r)\n", __FUNCTION__, Status));
  66     return Status;
  67   }
  68
  69   DEBUG ((EFI_D_INFO, "Found Xen node with Grant table @ 0x%Lx\n", RegBase));
  70
  71   return EFI_SUCCESS;
  72 }