Ovmf/Xen: move XenBusDxe hypercall code to separate library

This moves all of the Xen hypercall code that was private to XenBusDxe
to a new library class XenHypercallLib. This will allow us to reimplement
it for ARM, and to export the Xen hypercall functionality to other parts
of the code, such as a Xen console SerialPortLib driver.

Contributed-under: TianoCore Contribution Agreement 1.0
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16970 6f19259b-4bc3-4df7-8a09-765794883524

5 files changed, 243 insertions, 0 deletions

diff --git a/OvmfPkg/Library/XenHypercallLib/Ia32/hypercall.nasm b/OvmfPkg/Library/XenHypercallLib/Ia32/hypercall.nasm
new file mode 100644
index 0000000000..e0fa71bb5b
--- /dev/null
+++ b/OvmfPkg/Library/XenHypercallLib/Ia32/hypercall.nasm
@@ -0,0 +1,25 @@
+SECTION .text

+

+; INTN

+; EFIAPI

+; __XenHypercall2 (

+;   IN     VOID *HypercallAddr,

+;   IN OUT INTN Arg1,

+;   IN OUT INTN Arg2

+;   );

+global ASM_PFX(__XenHypercall2)

+ASM_PFX(__XenHypercall2):

+  ; Save only ebx, ecx is supposed to be a scratch register and needs to be

+  ; saved by the caller

+  push ebx

+  ; Copy HypercallAddr to eax

+  mov eax, [esp + 8]

+  ; Copy Arg1 to the register expected by Xen

+  mov ebx, [esp + 12]

+  ; Copy Arg2 to the register expected by Xen

+  mov ecx, [esp + 16]

+  ; Call HypercallAddr

+  call eax

+  pop ebx

+  ret

+

diff --git a/OvmfPkg/Library/XenHypercallLib/X64/hypercall.nasm b/OvmfPkg/Library/XenHypercallLib/X64/hypercall.nasm
new file mode 100644
index 0000000000..5e6a0c05c5
--- /dev/null
+++ b/OvmfPkg/Library/XenHypercallLib/X64/hypercall.nasm
@@ -0,0 +1,26 @@
+DEFAULT REL

+SECTION .text

+

+; INTN

+; EFIAPI

+; __XenHypercall2 (

+;   IN     VOID *HypercallAddr,

+;   IN OUT INTN Arg1,

+;   IN OUT INTN Arg2

+;   );

+global ASM_PFX(__XenHypercall2)

+ASM_PFX(__XenHypercall2):

+  push rdi

+  push rsi

+  ; Copy HypercallAddr to rax

+  mov rax, rcx

+  ; Copy Arg1 to the register expected by Xen

+  mov rdi, rdx

+  ; Copy Arg2 to the register expected by Xen

+  mov rsi, r8

+  ; Call HypercallAddr

+  call rax

+  pop rsi

+  pop rdi

+  ret

+

diff --git a/OvmfPkg/Library/XenHypercallLib/XenHypercall.c b/OvmfPkg/Library/XenHypercallLib/XenHypercall.c
new file mode 100644
index 0000000000..ecc757cf70
--- /dev/null
+++ b/OvmfPkg/Library/XenHypercallLib/XenHypercall.c
@@ -0,0 +1,63 @@
+/** @file

+  Functions to make Xen hypercalls.

+

+  Copyright (C) 2014, Citrix Ltd.

+

+  This program and the accompanying materials

+  are licensed and made available under the terms and conditions of the BSD License

+  which accompanies this distribution.  The full text of the license may be found at

+  http://opensource.org/licenses/bsd-license.php

+

+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+

+**/

+

+#include <PiDxe.h>

+

+#include <IndustryStandard/Xen/hvm/params.h>

+#include <IndustryStandard/Xen/memory.h>

+

+#include <Library/DebugLib.h>

+#include <Library/XenHypercallLib.h>

+

+UINT64

+XenHypercallHvmGetParam (

+  IN UINT32        Index

+  )

+{

+  xen_hvm_param_t     Parameter;

+  INTN                Error;

+

+  Parameter.domid = DOMID_SELF;

+  Parameter.index = Index;

+  Error = XenHypercall2 (__HYPERVISOR_hvm_op,

+                         HVMOP_get_param, (INTN) &Parameter);

+  if (Error != 0) {

+    DEBUG ((EFI_D_ERROR,

+            "XenHypercall: Error %d trying to get HVM parameter %d\n",

+            Error, Index));

+    return 0;

+  }

+  return Parameter.value;

+}

+

+INTN

+XenHypercallMemoryOp (

+  IN     UINTN Operation,

+  IN OUT VOID *Arguments

+  )

+{

+  return XenHypercall2 (__HYPERVISOR_memory_op,

+                        Operation, (INTN) Arguments);

+}

+

+INTN

+XenHypercallEventChannelOp (

+  IN     INTN Operation,

+  IN OUT VOID *Arguments

+  )

+{

+  return XenHypercall2 (__HYPERVISOR_event_channel_op,

+                        Operation, (INTN) Arguments);

+}

diff --git a/OvmfPkg/Library/XenHypercallLib/XenHypercallIntel.c b/OvmfPkg/Library/XenHypercallLib/XenHypercallIntel.c
new file mode 100644
index 0000000000..fc52823f23
--- /dev/null
+++ b/OvmfPkg/Library/XenHypercallLib/XenHypercallIntel.c
@@ -0,0 +1,77 @@
+/** @file

+  Xen Hypercall Library implementation for Intel architecture

+

+Copyright (c) 2014, Linaro Ltd. All rights reserved.<BR>

+This program and the accompanying materials are licensed and made available under

+the terms and conditions of the BSD License that accompanies this distribution.

+The full text of the license may be found at

+http://opensource.org/licenses/bsd-license.php.

+

+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+

+**/

+

+#include <PiDxe.h>

+#include <Library/HobLib.h>

+#include <Library/DebugLib.h>

+#include <Guid/XenInfo.h>

+

+STATIC VOID    *HyperPage;

+

+//

+// Interface exposed by the ASM implementation of the core hypercall

+//

+INTN

+EFIAPI

+__XenHypercall2 (

+  IN     VOID *HypercallAddr,

+  IN OUT INTN Arg1,

+  IN OUT INTN Arg2

+  );

+

+/**

+  Library constructor: retrieves the Hyperpage address

+  from the gEfiXenInfoGuid HOB

+**/

+

+RETURN_STATUS

+EFIAPI

+XenHypercallLibIntelInit (

+  VOID

+  )

+{

+  EFI_HOB_GUID_TYPE   *GuidHob;

+  EFI_XEN_INFO        *XenInfo;

+

+  GuidHob = GetFirstGuidHob (&gEfiXenInfoGuid);

+  if (GuidHob == NULL) {

+    return RETURN_NOT_FOUND;

+  }

+  XenInfo = (EFI_XEN_INFO *) GET_GUID_HOB_DATA (GuidHob);

+  HyperPage = XenInfo->HyperPages;

+  return RETURN_SUCCESS;

+}

+

+/**

+  This function will put the two arguments in the right place (registers) and

+  invoke the hypercall identified by HypercallID.

+

+  @param HypercallID    The symbolic ID of the hypercall to be invoked

+  @param Arg1           First argument.

+  @param Arg2           Second argument.

+

+  @return   Return 0 if success otherwise it return an errno.

+**/

+INTN

+EFIAPI

+XenHypercall2 (

+  IN     UINTN  HypercallID,

+  IN OUT INTN   Arg1,

+  IN OUT INTN   Arg2

+  )

+{

+  ASSERT (HyperPage != NULL);

+

+  return __XenHypercall2 ((UINT8*)HyperPage + HypercallID * 32, Arg1, Arg2);

+}

diff --git a/OvmfPkg/Library/XenHypercallLib/XenHypercallLibIntel.inf b/OvmfPkg/Library/XenHypercallLib/XenHypercallLibIntel.inf
new file mode 100644
index 0000000000..2afd608f4a
--- /dev/null
+++ b/OvmfPkg/Library/XenHypercallLib/XenHypercallLibIntel.inf
@@ -0,0 +1,52 @@
+## @file

+#  Xen Hypercall abstraction lib for Intel architecture

+#

+#  Copyright (c) 2014, Linaro Ltd. All rights reserved.<BR>

+#  This program and the accompanying materials

+#  are licensed and made available under the terms and conditions of the BSD License

+#  which accompanies this distribution.  The full text of the license may be found at

+#  http://opensource.org/licenses/bsd-license.php

+#

+#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

+#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+#

+##

+

+[Defines]

+  INF_VERSION                    = 0x00010005

+  BASE_NAME                      = XenHypercallLibIntel

+  FILE_GUID                      = B5EE9A32-CA5A-49A8-82E3-ADA4CCB77C7C

+  MODULE_TYPE                    = BASE

+  VERSION_STRING                 = 1.0

+  LIBRARY_CLASS                  = XenHypercallLib|DXE_DRIVER UEFI_DRIVER

+  CONSTRUCTOR                    = XenHypercallLibIntelInit

+

+#

+# The following information is for reference only and not required by the build tools.

+#

+#  VALID_ARCHITECTURES           = IA32 X64

+#

+

+[Sources]

+  XenHypercallIntel.c

+

+[Sources.IA32]

+  Ia32/hypercall.nasm

+

+[Sources.X64]

+  X64/hypercall.nasm

+

+[Sources]

+  XenHypercall.c

+

+[Packages]

+  MdePkg/MdePkg.dec

+  OvmfPkg/OvmfPkg.dec

+

+[LibraryClasses]

+  BaseLib

+  HobLib

+  DebugLib

+

+[Guids]

+  gEfiXenInfoGuid