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 *  SPDX-License-Identifier: BSD-2-Clause-Patent
   7 *
   8 **/
   9
  10 #include <Library/BaseLib.h>
  11 #include <Library/DebugLib.h>
  12 #include <Library/UefiDriverEntryPoint.h>
  13 #include <Library/UefiBootServicesTableLib.h>
  14 #include <Library/XenIoMmioLib.h>
  15
  16 #include <Protocol/FdtClient.h>
  17
  18 EFI_STATUS
  19 EFIAPI
  20 InitializeXenioFdtDxe (
  21   IN EFI_HANDLE           ImageHandle,
  22   IN EFI_SYSTEM_TABLE     *SystemTable
  23   )
  24 {
  25   EFI_STATUS            Status;
  26   FDT_CLIENT_PROTOCOL   *FdtClient;
  27   CONST UINT64          *Reg;
  28   UINT32                RegSize;
  29   UINTN                 AddressCells, SizeCells;
  30   EFI_HANDLE            Handle;
  31   UINT64                RegBase;
  32
  33   Status = gBS->LocateProtocol (&gFdtClientProtocolGuid, NULL,
  34                   (VOID **)&FdtClient);
  35   ASSERT_EFI_ERROR (Status);
  36
  37   Status = FdtClient->FindCompatibleNodeReg (FdtClient, "xen,xen",
  38                         (CONST VOID **)&Reg, &AddressCells, &SizeCells,
  39                         &RegSize);
  40   if (EFI_ERROR (Status)) {
  41     DEBUG ((EFI_D_WARN, "%a: No 'xen,xen' compatible DT node found\n",
  42       __FUNCTION__));
  43     return EFI_UNSUPPORTED;
  44   }
  45
  46   ASSERT (AddressCells == 2);
  47   ASSERT (SizeCells == 2);
  48   ASSERT (RegSize == 2 * sizeof (UINT64));
  49
  50   //
  51   // Retrieve the reg base from this node and wire it up to the
  52   // MMIO flavor of the XenBus root device I/O protocol
  53   //
  54   RegBase = SwapBytes64 (Reg[0]);
  55   Handle = NULL;
  56   Status = XenIoMmioInstall (&Handle, RegBase);
  57   if (EFI_ERROR (Status)) {
  58     DEBUG ((EFI_D_ERROR, "%a: XenIoMmioInstall () failed on a new handle "
  59       "(Status == %r)\n", __FUNCTION__, Status));
  60     return Status;
  61   }
  62
  63   DEBUG ((EFI_D_INFO, "Found Xen node with Grant table @ 0x%Lx\n", RegBase));
  64
  65   return EFI_SUCCESS;
  66 }