ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoPeiLibConstructor.c

   1 /** @file
   2
   3   Copyright (c) 2014-2017, Linaro Limited. All rights reserved.
   4
   5   This program and the accompanying materials are licensed and made available
   6   under the terms and conditions of the BSD License which accompanies this
   7   distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include <Base.h>
  16 #include <Library/DebugLib.h>
  17 #include <Library/PcdLib.h>
  18 #include <libfdt.h>
  19
  20 RETURN_STATUS
  21 EFIAPI
  22 QemuVirtMemInfoPeiLibConstructor (
  23   VOID
  24   )
  25 {
  26   VOID          *DeviceTreeBase;
  27   INT32         Node, Prev;
  28   UINT64        NewBase, CurBase;
  29   UINT64        NewSize, CurSize;
  30   CONST CHAR8   *Type;
  31   INT32         Len;
  32   CONST UINT64  *RegProp;
  33   RETURN_STATUS PcdStatus;
  34
  35   NewBase = 0;
  36   NewSize = 0;
  37
  38   DeviceTreeBase = (VOID *)(UINTN)PcdGet64 (PcdDeviceTreeInitialBaseAddress);
  39   ASSERT (DeviceTreeBase != NULL);
  40
  41   //
  42   // Make sure we have a valid device tree blob
  43   //
  44   ASSERT (fdt_check_header (DeviceTreeBase) == 0);
  45
  46   //
  47   // Look for the lowest memory node
  48   //
  49   for (Prev = 0;; Prev = Node) {
  50     Node = fdt_next_node (DeviceTreeBase, Prev, NULL);
  51     if (Node < 0) {
  52       break;
  53     }
  54
  55     //
  56     // Check for memory node
  57     //
  58     Type = fdt_getprop (DeviceTreeBase, Node, "device_type", &Len);
  59     if (Type && AsciiStrnCmp (Type, "memory", Len) == 0) {
  60       //
  61       // Get the 'reg' property of this node. For now, we will assume
  62       // two 8 byte quantities for base and size, respectively.
  63       //
  64       RegProp = fdt_getprop (DeviceTreeBase, Node, "reg", &Len);
  65       if (RegProp != 0 && Len == (2 * sizeof (UINT64))) {
  66
  67         CurBase = fdt64_to_cpu (ReadUnaligned64 (RegProp));
  68         CurSize = fdt64_to_cpu (ReadUnaligned64 (RegProp + 1));
  69
  70         DEBUG ((DEBUG_INFO, "%a: System RAM @ 0x%lx - 0x%lx\n",
  71           __FUNCTION__, CurBase, CurBase + CurSize - 1));
  72
  73         if (NewBase > CurBase || NewBase == 0) {
  74           NewBase = CurBase;
  75           NewSize = CurSize;
  76         }
  77       } else {
  78         DEBUG ((DEBUG_ERROR, "%a: Failed to parse FDT memory node\n",
  79           __FUNCTION__));
  80       }
  81     }
  82   }
  83
  84   //
  85   // Make sure the start of DRAM matches our expectation
  86   //
  87   ASSERT (FixedPcdGet64 (PcdSystemMemoryBase) == NewBase);
  88   PcdStatus = PcdSet64S (PcdSystemMemorySize, NewSize);
  89   ASSERT_RETURN_ERROR (PcdStatus);
  90
  91   //
  92   // We need to make sure that the machine we are running on has at least
  93   // 128 MB of memory configured, and is currently executing this binary from
  94   // NOR flash. This prevents a device tree image in DRAM from getting
  95   // clobbered when our caller installs permanent PEI RAM, before we have a
  96   // chance of marking its location as reserved or copy it to a freshly
  97   // allocated block in the permanent PEI RAM in the platform PEIM.
  98   //
  99   ASSERT (NewSize >= SIZE_128MB);
 100   ASSERT (
 101     (((UINT64)PcdGet64 (PcdFdBaseAddress) +
 102       (UINT64)PcdGet32 (PcdFdSize)) <= NewBase) ||
 103     ((UINT64)PcdGet64 (PcdFdBaseAddress) >= (NewBase + NewSize)));
 104
 105   return RETURN_SUCCESS;
 106 }