OvmfPkg/XenPlatformPei: Grab RSDP from PVH guest start of day struct

Check if there's a start of the day struct provided to PVH guest, save
the ACPI RSDP address for later.

This patch import import arch-x86/hvm/start_info.h from xen.git.

Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1689
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20190813113119.14804-13-anthony.perard@citrix.com>

4 files changed, 175 insertions, 0 deletions

diff --git a/OvmfPkg/Include/Guid/XenInfo.h b/OvmfPkg/Include/Guid/XenInfo.h
index b052d618fd..25743b3884 100644
--- a/OvmfPkg/Include/Guid/XenInfo.h
+++ b/OvmfPkg/Include/Guid/XenInfo.h
@@ -25,6 +25,10 @@ typedef struct {
   /// Hypervisor minor version.

   ///

   UINT16 VersionMinor;

+  ///

+  /// Pointer to the RSDP found in the hvm_start_info provided to a PVH guest

+  ///

+  VOID *RsdpPvh;

 } EFI_XEN_INFO;

 

 extern EFI_GUID gEfiXenInfoGuid;

diff --git a/OvmfPkg/Include/IndustryStandard/Xen/arch-x86/hvm/start_info.h b/OvmfPkg/Include/IndustryStandard/Xen/arch-x86/hvm/start_info.h
new file mode 100644
index 0000000000..15708d6dd5
--- /dev/null
+++ b/OvmfPkg/Include/IndustryStandard/Xen/arch-x86/hvm/start_info.h
@@ -0,0 +1,143 @@
+/*

+ * SPDX-License-Identifier: MIT

+ *

+ * Copyright (c) 2016, Citrix Systems, Inc.

+ */

+

+#ifndef __XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H__

+#define __XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H__

+

+/*

+ * Start of day structure passed to PVH guests and to HVM guests in %ebx.

+ *

+ * NOTE: nothing will be loaded at physical address 0, so a 0 value in any

+ * of the address fields should be treated as not present.

+ *

+ *  0 +----------------+

+ *    | magic          | Contains the magic value XEN_HVM_START_MAGIC_VALUE

+ *    |                | ("xEn3" with the 0x80 bit of the "E" set).

+ *  4 +----------------+

+ *    | version        | Version of this structure. Current version is 1. New

+ *    |                | versions are guaranteed to be backwards-compatible.

+ *  8 +----------------+

+ *    | flags          | SIF_xxx flags.

+ * 12 +----------------+

+ *    | nr_modules     | Number of modules passed to the kernel.

+ * 16 +----------------+

+ *    | modlist_paddr  | Physical address of an array of modules

+ *    |                | (layout of the structure below).

+ * 24 +----------------+

+ *    | cmdline_paddr  | Physical address of the command line,

+ *    |                | a zero-terminated ASCII string.

+ * 32 +----------------+

+ *    | rsdp_paddr     | Physical address of the RSDP ACPI data structure.

+ * 40 +----------------+

+ *    | memmap_paddr   | Physical address of the (optional) memory map. Only

+ *    |                | present in version 1 and newer of the structure.

+ * 48 +----------------+

+ *    | memmap_entries | Number of entries in the memory map table. Zero

+ *    |                | if there is no memory map being provided. Only

+ *    |                | present in version 1 and newer of the structure.

+ * 52 +----------------+

+ *    | reserved       | Version 1 and newer only.

+ * 56 +----------------+

+ *

+ * The layout of each entry in the module structure is the following:

+ *

+ *  0 +----------------+

+ *    | paddr          | Physical address of the module.

+ *  8 +----------------+

+ *    | size           | Size of the module in bytes.

+ * 16 +----------------+

+ *    | cmdline_paddr  | Physical address of the command line,

+ *    |                | a zero-terminated ASCII string.

+ * 24 +----------------+

+ *    | reserved       |

+ * 32 +----------------+

+ *

+ * The layout of each entry in the memory map table is as follows:

+ *

+ *  0 +----------------+

+ *    | addr           | Base address

+ *  8 +----------------+

+ *    | size           | Size of mapping in bytes

+ * 16 +----------------+

+ *    | type           | Type of mapping as defined between the hypervisor

+ *    |                | and guest. See XEN_HVM_MEMMAP_TYPE_* values below.

+ * 20 +----------------|

+ *    | reserved       |

+ * 24 +----------------+

+ *

+ * The address and sizes are always a 64bit little endian unsigned integer.

+ *

+ * NB: Xen on x86 will always try to place all the data below the 4GiB

+ * boundary.

+ *

+ * Version numbers of the hvm_start_info structure have evolved like this:

+ *

+ * Version 0:  Initial implementation.

+ *

+ * Version 1:  Added the memmap_paddr/memmap_entries fields (plus 4 bytes of

+ *             padding) to the end of the hvm_start_info struct. These new

+ *             fields can be used to pass a memory map to the guest. The

+ *             memory map is optional and so guests that understand version 1

+ *             of the structure must check that memmap_entries is non-zero

+ *             before trying to read the memory map.

+ */

+#define XEN_HVM_START_MAGIC_VALUE 0x336ec578

+

+/*

+ * The values used in the type field of the memory map table entries are

+ * defined below and match the Address Range Types as defined in the "System

+ * Address Map Interfaces" section of the ACPI Specification. Please refer to

+ * section 15 in version 6.2 of the ACPI spec: http://uefi.org/specifications

+ */

+#define XEN_HVM_MEMMAP_TYPE_RAM       1

+#define XEN_HVM_MEMMAP_TYPE_RESERVED  2

+#define XEN_HVM_MEMMAP_TYPE_ACPI      3

+#define XEN_HVM_MEMMAP_TYPE_NVS       4

+#define XEN_HVM_MEMMAP_TYPE_UNUSABLE  5

+#define XEN_HVM_MEMMAP_TYPE_DISABLED  6

+#define XEN_HVM_MEMMAP_TYPE_PMEM      7

+

+/*

+ * C representation of the x86/HVM start info layout.

+ *

+ * The canonical definition of this layout is above, this is just a way to

+ * represent the layout described there using C types.

+ */

+struct hvm_start_info {

+    UINT32 magic;             /* Contains the magic value 0x336ec578       */

+                              /* ("xEn3" with the 0x80 bit of the "E" set).*/

+    UINT32 version;           /* Version of this structure.                */

+    UINT32 flags;             /* SIF_xxx flags.                            */

+    UINT32 nr_modules;        /* Number of modules passed to the kernel.   */

+    UINT64 modlist_paddr;     /* Physical address of an array of           */

+                              /* hvm_modlist_entry.                        */

+    UINT64 cmdline_paddr;     /* Physical address of the command line.     */

+    UINT64 rsdp_paddr;        /* Physical address of the RSDP ACPI data    */

+                              /* structure.                                */

+    /* All following fields only present in version 1 and newer */

+    UINT64 memmap_paddr;      /* Physical address of an array of           */

+                              /* hvm_memmap_table_entry.                   */

+    UINT32 memmap_entries;    /* Number of entries in the memmap table.    */

+                              /* Value will be zero if there is no memory  */

+                              /* map being provided.                       */

+    UINT32 reserved;          /* Must be zero.                             */

+};

+

+struct hvm_modlist_entry {

+    UINT64 paddr;             /* Physical address of the module.           */

+    UINT64 size;              /* Size of the module in bytes.              */

+    UINT64 cmdline_paddr;     /* Physical address of the command line.     */

+    UINT64 reserved;

+};

+

+struct hvm_memmap_table_entry {

+    UINT64 addr;              /* Base address of the memory region         */

+    UINT64 size;              /* Size of the memory region in bytes        */

+    UINT32 type;              /* Mapping type                              */

+    UINT32 reserved;          /* Must be zero for Version 1.               */

+};

+

+#endif /* __XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H__ */

diff --git a/OvmfPkg/XenPlatformPei/Xen.c b/OvmfPkg/XenPlatformPei/Xen.c
index 5c7d7ddc1c..b366139a0a 100644
--- a/OvmfPkg/XenPlatformPei/Xen.c
+++ b/OvmfPkg/XenPlatformPei/Xen.c
@@ -25,6 +25,7 @@
 #include <IndustryStandard/E820.h>

 #include <Library/ResourcePublicationLib.h>

 #include <Library/MtrrLib.h>

+#include <IndustryStandard/Xen/arch-x86/hvm/start_info.h>

 

 #include "Platform.h"

 #include "Xen.h"

@@ -86,6 +87,7 @@ XenConnect (
   UINT32 XenVersion;

   EFI_XEN_OVMF_INFO *Info;

   CHAR8 Sig[sizeof (Info->Signature) + 1];

+  UINT32 *PVHResetVectorData;

 

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

   mXenInfo.HyperPages = AllocatePages (TransferPages);

@@ -121,6 +123,29 @@ XenConnect (
     mXenHvmloaderInfo = NULL;

   }

 

+  mXenInfo.RsdpPvh = NULL;

+

+  //

+  // Locate and use information from the start of day structure if we have

+  // booted via the PVH entry point.

+  //

+

+  PVHResetVectorData = (VOID *)(UINTN) PcdGet32 (PcdXenPvhStartOfDayStructPtr);

+  //

+  // That magic value is written in XenResetVector/Ia32/XenPVHMain.asm

+  //

+  if (PVHResetVectorData[1] == SIGNATURE_32 ('X', 'P', 'V', 'H')) {

+    struct hvm_start_info *HVMStartInfo;

+

+    HVMStartInfo = (VOID *)(UINTN) PVHResetVectorData[0];

+    if (HVMStartInfo->magic == XEN_HVM_START_MAGIC_VALUE) {

+      ASSERT (HVMStartInfo->rsdp_paddr != 0);

+      if (HVMStartInfo->rsdp_paddr != 0) {

+        mXenInfo.RsdpPvh = (VOID *)(UINTN)HVMStartInfo->rsdp_paddr;

+      }

+    }

+  }

+

   BuildGuidDataHob (

     &gEfiXenInfoGuid,

     &mXenInfo,

diff --git a/OvmfPkg/XenPlatformPei/XenPlatformPei.inf b/OvmfPkg/XenPlatformPei/XenPlatformPei.inf
index d1265c365a..4d00206d09 100644
--- a/OvmfPkg/XenPlatformPei/XenPlatformPei.inf
+++ b/OvmfPkg/XenPlatformPei/XenPlatformPei.inf
@@ -84,6 +84,9 @@
   gEfiSecurityPkgTokenSpaceGuid.PcdOptionRomImageVerificationPolicy

   gUefiCpuPkgTokenSpaceGuid.PcdCpuLocalApicBaseAddress

 

+  gUefiOvmfPkgTokenSpaceGuid.PcdXenPvhStartOfDayStructPtr

+  gUefiOvmfPkgTokenSpaceGuid.PcdXenPvhStartOfDayStructPtrSize

+

 [FixedPcd]

   gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress