ArmVirtPkg/Library/NorFlashQemuLib/NorFlashQemuLib.c

   1 /** @file
   2
   3  Copyright (c) 2014-2018, Linaro Ltd. All rights reserved.<BR>
   4
   5  SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7  **/
   8
   9 #include <Library/BaseLib.h>
  10 #include <Library/DebugLib.h>
  11 #include <Library/UefiBootServicesTableLib.h>
  12 #include <Library/VirtNorFlashPlatformLib.h>
  13
  14 #include <Protocol/FdtClient.h>
  15
  16 #define QEMU_NOR_BLOCK_SIZE  SIZE_256KB
  17
  18 #define MAX_FLASH_BANKS  4
  19
  20 EFI_STATUS
  21 VirtNorFlashPlatformInitialization (
  22   VOID
  23   )
  24 {
  25   return EFI_SUCCESS;
  26 }
  27
  28 STATIC VIRT_NOR_FLASH_DESCRIPTION  mNorFlashDevices[MAX_FLASH_BANKS];
  29
  30 EFI_STATUS
  31 VirtNorFlashPlatformGetDevices (
  32   OUT VIRT_NOR_FLASH_DESCRIPTION  **NorFlashDescriptions,
  33   OUT UINT32                      *Count
  34   )
  35 {
  36   FDT_CLIENT_PROTOCOL  *FdtClient;
  37   INT32                Node;
  38   EFI_STATUS           Status;
  39   EFI_STATUS           FindNodeStatus;
  40   CONST UINT32         *Reg;
  41   UINT32               PropSize;
  42   UINT32               Num;
  43   UINT64               Base;
  44   UINT64               Size;
  45
  46   Status = gBS->LocateProtocol (
  47                   &gFdtClientProtocolGuid,
  48                   NULL,
  49                   (VOID **)&FdtClient
  50                   );
  51   ASSERT_EFI_ERROR (Status);
  52
  53   Num = 0;
  54   for (FindNodeStatus = FdtClient->FindCompatibleNode (
  55                                      FdtClient,
  56                                      "cfi-flash",
  57                                      &Node
  58                                      );
  59        !EFI_ERROR (FindNodeStatus) && Num < MAX_FLASH_BANKS;
  60        FindNodeStatus = FdtClient->FindNextCompatibleNode (
  61                                      FdtClient,
  62                                      "cfi-flash",
  63                                      Node,
  64                                      &Node
  65                                      ))
  66   {
  67     Status = FdtClient->GetNodeProperty (
  68                           FdtClient,
  69                           Node,
  70                           "reg",
  71                           (CONST VOID **)&Reg,
  72                           &PropSize
  73                           );
  74     if (EFI_ERROR (Status)) {
  75       DEBUG ((
  76         DEBUG_ERROR,
  77         "%a: GetNodeProperty () failed (Status == %r)\n",
  78         __FUNCTION__,
  79         Status
  80         ));
  81       continue;
  82     }
  83
  84     ASSERT ((PropSize % (4 * sizeof (UINT32))) == 0);
  85
  86     while (PropSize >= (4 * sizeof (UINT32)) && Num < MAX_FLASH_BANKS) {
  87       Base = SwapBytes64 (ReadUnaligned64 ((VOID *)&Reg[0]));
  88       Size = SwapBytes64 (ReadUnaligned64 ((VOID *)&Reg[2]));
  89       Reg += 4;
  90
  91       PropSize -= 4 * sizeof (UINT32);
  92
  93       //
  94       // Disregard any flash devices that overlap with the primary FV.
  95       // The firmware is not updatable from inside the guest anyway.
  96       //
  97       if ((PcdGet64 (PcdFvBaseAddress) + PcdGet32 (PcdFvSize) > Base) &&
  98           ((Base + Size) > PcdGet64 (PcdFvBaseAddress)))
  99       {
 100         continue;
 101       }
 102
 103       mNorFlashDevices[Num].DeviceBaseAddress = (UINTN)Base;
 104       mNorFlashDevices[Num].RegionBaseAddress = (UINTN)Base;
 105       mNorFlashDevices[Num].Size              = (UINTN)Size;
 106       mNorFlashDevices[Num].BlockSize         = QEMU_NOR_BLOCK_SIZE;
 107       Num++;
 108     }
 109
 110     //
 111     // UEFI takes ownership of the NOR flash, and exposes its functionality
 112     // through the UEFI Runtime Services GetVariable, SetVariable, etc. This
 113     // means we need to disable it in the device tree to prevent the OS from
 114     // attaching its device driver as well.
 115     // Note that this also hides other flash banks, but the only other flash
 116     // bank we expect to encounter is the one that carries the UEFI executable
 117     // code, which is not intended to be guest updatable, and is usually backed
 118     // in a readonly manner by QEMU anyway.
 119     //
 120     Status = FdtClient->SetNodeProperty (
 121                           FdtClient,
 122                           Node,
 123                           "status",
 124                           "disabled",
 125                           sizeof ("disabled")
 126                           );
 127     if (EFI_ERROR (Status)) {
 128       DEBUG ((DEBUG_WARN, "Failed to set NOR flash status to 'disabled'\n"));
 129     }
 130   }
 131
 132   *NorFlashDescriptions = mNorFlashDevices;
 133   *Count                = Num;
 134
 135   return EFI_SUCCESS;
 136 }