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 (
  34                   &gFdtClientProtocolGuid,
  35                   NULL,
  36                   (VOID **)&FdtClient
  37                   );
  38   ASSERT_EFI_ERROR (Status);
  39
  40   Status = FdtClient->FindCompatibleNodeReg (
  41                         FdtClient,
  42                         "xen,xen",
  43                         (CONST VOID **)&Reg,
  44                         &AddressCells,
  45                         &SizeCells,
  46                         &RegSize
  47                         );
  48   if (EFI_ERROR (Status)) {
  49     DEBUG ((
  50       DEBUG_WARN,
  51       "%a: No 'xen,xen' compatible DT node found\n",
  52       __FUNCTION__
  53       ));
  54     return EFI_UNSUPPORTED;
  55   }
  56
  57   ASSERT (AddressCells == 2);
  58   ASSERT (SizeCells == 2);
  59   ASSERT (RegSize == 2 * sizeof (UINT64));
  60
  61   //
  62   // Retrieve the reg base from this node and wire it up to the
  63   // MMIO flavor of the XenBus root device I/O protocol
  64   //
  65   RegBase = SwapBytes64 (Reg[0]);
  66   Handle  = NULL;
  67   Status  = XenIoMmioInstall (&Handle, RegBase);
  68   if (EFI_ERROR (Status)) {
  69     DEBUG ((
  70       DEBUG_ERROR,
  71       "%a: XenIoMmioInstall () failed on a new handle "
  72       "(Status == %r)\n",
  73       __FUNCTION__,
  74       Status
  75       ));
  76     return Status;
  77   }
  78
  79   DEBUG ((DEBUG_INFO, "Found Xen node with Grant table @ 0x%Lx\n", RegBase));
  80
  81   return EFI_SUCCESS;
  82 }