OvmfPkg: Introduce XenPlatformPei

Introduce XenPlatformPei, a copy of OvmfPkg/PlatformPei without some
of QEMU specific initialization, Xen does not support QemuFwCfg.

This new module will be adjusted to accommodate Xen PVH.

fw_cfg dependents that have been removed, which are dynamically skipped
when running PlatformPei on Xen:
- GetFirstNonAddress(): controlling the 64-bit PCI MMIO aperture via the
(experimental) "opt/ovmf/X-PciMmio64Mb" file
- GetFirstNonAddress(): honoring the hotplug DIMM area
("etc/reserved-memory-end") in the placement of the 64-bit PCI MMIO
aperture
- NoexecDxeInitialization() is removed, so PcdPropertiesTableEnable and
PcdSetNxForStack are left constant FALSE (not set dynamically from
fw_cfg "opt/ovmf/PcdXxxx")
- MaxCpuCountInitialization(), PublishPeiMemory(): the max CPU count is
not taken from the QemuFwCfgItemSmpCpuCount fw_cfg key;
PcdCpuMaxLogicalProcessorNumber is used intact and
PcdCpuApInitTimeOutInMicroSeconds is never changed or used.
- InitializeXenPlatform(), S3Verification(): S3 is assumed disabled (not
consulting "etc/system-states" via QemuFwCfgS3Enabled()).
- InstallFeatureControlCallback(): the feature control MSR is not set
from "etc/msr_feature_control"
(also removed FeatureControl.c as there is nothing been executed)

Also removed:
- SMRAM/TSEG-related low mem size adjusting (PcdSmmSmramRequire is
assumed FALSE) in PublishPeiMemory(),
- QemuInitializeRam() entirely,

Xen related changes:
- Have removed the module variable mXen, as it should be always true.
- Have the platform PEI initialization fails if Xen has not been
  detected.

Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1689
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20190813113119.14804-5-anthony.perard@citrix.com>

1 files changed, 219 insertions, 0 deletions

diff --git a/OvmfPkg/XenPlatformPei/Xen.c b/OvmfPkg/XenPlatformPei/Xen.c
new file mode 100644
index 0000000000..f4d0d1c73b
--- /dev/null
+++ b/OvmfPkg/XenPlatformPei/Xen.c
@@ -0,0 +1,219 @@
+/**@file

+  Xen Platform PEI support

+

+  Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>

+  Copyright (c) 2011, Andrei Warkentin <andreiw@motorola.com>

+  Copyright (c) 2019, Citrix Systems, Inc.

+

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+

+**/

+

+//

+// The package level header files this module uses

+//

+#include <PiPei.h>

+

+//

+// The Library classes this module consumes

+//

+#include <Library/DebugLib.h>

+#include <Library/HobLib.h>

+#include <Library/MemoryAllocationLib.h>

+#include <Library/PcdLib.h>

+#include <Guid/XenInfo.h>

+#include <IndustryStandard/E820.h>

+#include <Library/ResourcePublicationLib.h>

+#include <Library/MtrrLib.h>

+

+#include "Platform.h"

+#include "Xen.h"

+

+STATIC UINT32 mXenLeaf = 0;

+

+EFI_XEN_INFO mXenInfo;

+

+/**

+  Returns E820 map provided by Xen

+

+  @param Entries      Pointer to E820 map

+  @param Count        Number of entries

+

+  @return EFI_STATUS

+**/

+EFI_STATUS

+XenGetE820Map (

+  EFI_E820_ENTRY64 **Entries,

+  UINT32 *Count

+  )

+{

+  EFI_XEN_OVMF_INFO *Info =

+    (EFI_XEN_OVMF_INFO *)(UINTN) OVMF_INFO_PHYSICAL_ADDRESS;

+

+  if (AsciiStrCmp ((CHAR8 *) Info->Signature, "XenHVMOVMF")) {

+    return EFI_NOT_FOUND;

+  }

+

+  ASSERT (Info->E820 < MAX_ADDRESS);

+  *Entries = (EFI_E820_ENTRY64 *)(UINTN) Info->E820;

+  *Count = Info->E820EntriesCount;

+

+  return EFI_SUCCESS;

+}

+

+/**

+  Connects to the Hypervisor.

+

+  @param  XenLeaf     CPUID index used to connect.

+

+  @return EFI_STATUS

+

+**/

+EFI_STATUS

+XenConnect (

+  UINT32 XenLeaf

+  )

+{

+  UINT32 Index;

+  UINT32 TransferReg;

+  UINT32 TransferPages;

+  UINT32 XenVersion;

+

+  AsmCpuid (XenLeaf + 2, &TransferPages, &TransferReg, NULL, NULL);

+  mXenInfo.HyperPages = AllocatePages (TransferPages);

+  if (!mXenInfo.HyperPages) {

+    return EFI_OUT_OF_RESOURCES;

+  }

+

+  for (Index = 0; Index < TransferPages; Index++) {

+    AsmWriteMsr64 (TransferReg,

+                   (UINTN) mXenInfo.HyperPages +

+                   (Index << EFI_PAGE_SHIFT) + Index);

+  }

+

+  AsmCpuid (XenLeaf + 1, &XenVersion, NULL, NULL, NULL);

+  DEBUG ((DEBUG_ERROR, "Detected Xen version %d.%d\n",

+          XenVersion >> 16, XenVersion & 0xFFFF));

+  mXenInfo.VersionMajor = (UINT16)(XenVersion >> 16);

+  mXenInfo.VersionMinor = (UINT16)(XenVersion & 0xFFFF);

+

+  /* TBD: Locate hvm_info and reserve it away. */

+  mXenInfo.HvmInfo = NULL;

+

+  BuildGuidDataHob (

+    &gEfiXenInfoGuid,

+    &mXenInfo,

+    sizeof(mXenInfo)

+    );

+

+  return EFI_SUCCESS;

+}

+

+/**

+  Figures out if we are running inside Xen HVM.

+

+  @retval TRUE   Xen was detected

+  @retval FALSE  Xen was not detected

+

+**/

+BOOLEAN

+XenDetect (

+  VOID

+  )

+{

+  UINT8 Signature[13];

+

+  if (mXenLeaf != 0) {

+    return TRUE;

+  }

+

+  Signature[12] = '\0';

+  for (mXenLeaf = 0x40000000; mXenLeaf < 0x40010000; mXenLeaf += 0x100) {

+    AsmCpuid (mXenLeaf,

+              NULL,

+              (UINT32 *) &Signature[0],

+              (UINT32 *) &Signature[4],

+              (UINT32 *) &Signature[8]);

+

+    if (!AsciiStrCmp ((CHAR8 *) Signature, "XenVMMXenVMM")) {

+      return TRUE;

+    }

+  }

+

+  mXenLeaf = 0;

+  return FALSE;

+}

+

+

+VOID

+XenPublishRamRegions (

+  VOID

+  )

+{

+  EFI_E820_ENTRY64  *E820Map;

+  UINT32            E820EntriesCount;

+  EFI_STATUS        Status;

+

+  DEBUG ((DEBUG_INFO, "Using memory map provided by Xen\n"));

+

+  //

+  // Parse RAM in E820 map

+  //

+  E820EntriesCount = 0;

+  Status = XenGetE820Map (&E820Map, &E820EntriesCount);

+

+  ASSERT_EFI_ERROR (Status);

+

+  if (E820EntriesCount > 0) {

+    EFI_E820_ENTRY64 *Entry;

+    UINT32 Loop;

+

+    for (Loop = 0; Loop < E820EntriesCount; Loop++) {

+      Entry = E820Map + Loop;

+

+      //

+      // Only care about RAM

+      //

+      if (Entry->Type != EfiAcpiAddressRangeMemory) {

+        continue;

+      }

+

+      AddMemoryBaseSizeHob (Entry->BaseAddr, Entry->Length);

+

+      MtrrSetMemoryAttribute (Entry->BaseAddr, Entry->Length, CacheWriteBack);

+    }

+  }

+}

+

+

+/**

+  Perform Xen PEI initialization.

+

+  @return EFI_SUCCESS     Xen initialized successfully

+  @return EFI_NOT_FOUND   Not running under Xen

+

+**/

+EFI_STATUS

+InitializeXen (

+  VOID

+  )

+{

+  RETURN_STATUS PcdStatus;

+

+  if (mXenLeaf == 0) {

+    return EFI_NOT_FOUND;

+  }

+

+  XenConnect (mXenLeaf);

+

+  //

+  // Reserve away HVMLOADER reserved memory [0xFC000000,0xFD000000).

+  // This needs to match HVMLOADER RESERVED_MEMBASE/RESERVED_MEMSIZE.

+  //

+  AddReservedMemoryBaseSizeHob (0xFC000000, 0x1000000, FALSE);

+

+  PcdStatus = PcdSetBoolS (PcdPciDisableBusEnumeration, TRUE);

+  ASSERT_RETURN_ERROR (PcdStatus);

+

+  return EFI_SUCCESS;

+}