OvmfPkg/PlatformPei/Xen.c

   1 /**@file
   2   Xen Platform PEI support
   3
   4   Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
   5   Copyright (c) 2011, Andrei Warkentin <andreiw@motorola.com>
   6
   7   This program and the accompanying materials
   8   are licensed and made available under the terms and conditions of the BSD License
   9   which accompanies this distribution.  The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 //
  18 // The package level header files this module uses
  19 //
  20 #include <PiPei.h>
  21
  22 //
  23 // The Library classes this module consumes
  24 //
  25 #include <Library/DebugLib.h>
  26 #include <Library/HobLib.h>
  27 #include <Library/MemoryAllocationLib.h>
  28 #include <Library/PcdLib.h>
  29 #include <Guid/XenInfo.h>
  30 #include <IndustryStandard/E820.h>
  31 #include <Library/ResourcePublicationLib.h>
  32 #include <Library/MtrrLib.h>
  33
  34 #include "Platform.h"
  35 #include "Xen.h"
  36
  37 BOOLEAN mXen = FALSE;
  38
  39 STATIC UINT32 mXenLeaf = 0;
  40
  41 EFI_XEN_INFO mXenInfo;
  42
  43 /**
  44   Returns E820 map provided by Xen
  45
  46   @param Entries      Pointer to E820 map
  47   @param Count        Number of entries
  48
  49   @return EFI_STATUS
  50 **/
  51 EFI_STATUS
  52 XenGetE820Map (
  53   EFI_E820_ENTRY64 **Entries,
  54   UINT32 *Count
  55   )
  56 {
  57   EFI_XEN_OVMF_INFO *Info =
  58     (EFI_XEN_OVMF_INFO *)(UINTN) OVMF_INFO_PHYSICAL_ADDRESS;
  59
  60   if (AsciiStrCmp ((CHAR8 *) Info->Signature, "XenHVMOVMF")) {
  61     return EFI_NOT_FOUND;
  62   }
  63
  64   ASSERT (Info->E820 < MAX_ADDRESS);
  65   *Entries = (EFI_E820_ENTRY64 *)(UINTN) Info->E820;
  66   *Count = Info->E820EntriesCount;
  67
  68   return EFI_SUCCESS;
  69 }
  70
  71 /**
  72   Connects to the Hypervisor.
  73
  74   @param  XenLeaf     CPUID index used to connect.
  75
  76   @return EFI_STATUS
  77
  78 **/
  79 EFI_STATUS
  80 XenConnect (
  81   UINT32 XenLeaf
  82   )
  83 {
  84   UINT32 Index;
  85   UINT32 TransferReg;
  86   UINT32 TransferPages;
  87   UINT32 XenVersion;
  88
  89   AsmCpuid (XenLeaf + 2, &TransferPages, &TransferReg, NULL, NULL);
  90   mXenInfo.HyperPages = AllocatePages (TransferPages);
  91   if (!mXenInfo.HyperPages) {
  92     return EFI_OUT_OF_RESOURCES;
  93   }
  94
  95   for (Index = 0; Index < TransferPages; Index++) {
  96     AsmWriteMsr64 (TransferReg,
  97                    (UINTN) mXenInfo.HyperPages +
  98                    (Index << EFI_PAGE_SHIFT) + Index);
  99   }
 100
 101   AsmCpuid (XenLeaf + 1, &XenVersion, NULL, NULL, NULL);
 102   DEBUG ((EFI_D_ERROR, "Detected Xen version %d.%d\n",
 103           XenVersion >> 16, XenVersion & 0xFFFF));
 104   mXenInfo.VersionMajor = (UINT16)(XenVersion >> 16);
 105   mXenInfo.VersionMinor = (UINT16)(XenVersion & 0xFFFF);
 106
 107   /* TBD: Locate hvm_info and reserve it away. */
 108   mXenInfo.HvmInfo = NULL;
 109
 110   BuildGuidDataHob (
 111     &gEfiXenInfoGuid,
 112     &mXenInfo,
 113     sizeof(mXenInfo)
 114     );
 115
 116   return EFI_SUCCESS;
 117 }
 118
 119 /**
 120   Figures out if we are running inside Xen HVM.
 121
 122   @retval TRUE   Xen was detected
 123   @retval FALSE  Xen was not detected
 124
 125 **/
 126 BOOLEAN
 127 XenDetect (
 128   VOID
 129   )
 130 {
 131   UINT8 Signature[13];
 132
 133   if (mXenLeaf != 0) {
 134     return TRUE;
 135   }
 136
 137   Signature[12] = '\0';
 138   for (mXenLeaf = 0x40000000; mXenLeaf < 0x40010000; mXenLeaf += 0x100) {
 139     AsmCpuid (mXenLeaf,
 140               NULL,
 141               (UINT32 *) &Signature[0],
 142               (UINT32 *) &Signature[4],
 143               (UINT32 *) &Signature[8]);
 144
 145     if (!AsciiStrCmp ((CHAR8 *) Signature, "XenVMMXenVMM")) {
 146       mXen = TRUE;
 147       return TRUE;
 148     }
 149   }
 150
 151   mXenLeaf = 0;
 152   return FALSE;
 153 }
 154
 155
 156 VOID
 157 XenPublishRamRegions (
 158   VOID
 159   )
 160 {
 161   EFI_E820_ENTRY64  *E820Map;
 162   UINT32            E820EntriesCount;
 163   EFI_STATUS        Status;
 164
 165   if (!mXen) {
 166     return;
 167   }
 168
 169   DEBUG ((EFI_D_INFO, "Using memory map provided by Xen\n"));
 170
 171   //
 172   // Parse RAM in E820 map
 173   //
 174   Status = XenGetE820Map (&E820Map, &E820EntriesCount);
 175
 176   ASSERT_EFI_ERROR (Status);
 177
 178   if (E820EntriesCount > 0) {
 179     EFI_E820_ENTRY64 *Entry;
 180     UINT32 Loop;
 181
 182     for (Loop = 0; Loop < E820EntriesCount; Loop++) {
 183       Entry = E820Map + Loop;
 184
 185       //
 186       // Only care about RAM
 187       //
 188       if (Entry->Type != EfiAcpiAddressRangeMemory) {
 189         continue;
 190       }
 191
 192       if (Entry->BaseAddr >= BASE_4GB) {
 193         AddUntestedMemoryBaseSizeHob (Entry->BaseAddr, Entry->Length);
 194       } else {
 195         AddMemoryBaseSizeHob (Entry->BaseAddr, Entry->Length);
 196       }
 197
 198       MtrrSetMemoryAttribute (Entry->BaseAddr, Entry->Length, CacheWriteBack);
 199     }
 200   }
 201 }
 202
 203
 204 /**
 205   Perform Xen PEI initialization.
 206
 207   @return EFI_SUCCESS     Xen initialized successfully
 208   @return EFI_NOT_FOUND   Not running under Xen
 209
 210 **/
 211 EFI_STATUS
 212 InitializeXen (
 213   VOID
 214   )
 215 {
 216   if (mXenLeaf == 0) {
 217     return EFI_NOT_FOUND;
 218   }
 219
 220   XenConnect (mXenLeaf);
 221
 222   //
 223   // Reserve away HVMLOADER reserved memory [0xFC000000,0xFD000000).
 224   // This needs to match HVMLOADER RESERVED_MEMBASE/RESERVED_MEMSIZE.
 225   //
 226   AddReservedMemoryBaseSizeHob (0xFC000000, 0x1000000);
 227
 228   return EFI_SUCCESS;
 229 }