OvmfPkg/XenBusDxe/XenHypercall.c

   1 /** @file
   2   Functions to make Xen hypercalls.
   3
   4   Copyright (C) 2014, Citrix Ltd.
   5
   6   This program and the accompanying materials
   7   are licensed and made available under the terms and conditions of the BSD License
   8   which accompanies this distribution.  The full text of the license may be found at
   9   http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13
  14 **/
  15
  16 #include <PiDxe.h>
  17 #include <Library/HobLib.h>
  18 #include <Guid/XenInfo.h>
  19
  20 #include "XenBusDxe.h"
  21 #include "XenHypercall.h"
  22
  23 #include <IndustryStandard/Xen/hvm/params.h>
  24 #include <IndustryStandard/Xen/memory.h>
  25
  26 STATIC VOID       *HyperPage;
  27
  28 //
  29 // Interface exposed by the ASM implementation of the core hypercall
  30 //
  31 INTN
  32 EFIAPI
  33 __XenHypercall2 (
  34   IN     VOID *HypercallAddr,
  35   IN OUT INTN Arg1,
  36   IN OUT INTN Arg2
  37   );
  38
  39 EFI_STATUS
  40 XenHyperpageInit (
  41   )
  42 {
  43   EFI_HOB_GUID_TYPE   *GuidHob;
  44   EFI_XEN_INFO        *XenInfo;
  45
  46   GuidHob = GetFirstGuidHob (&gEfiXenInfoGuid);
  47   if (GuidHob == NULL) {
  48     return EFI_NOT_FOUND;
  49   }
  50   XenInfo = (EFI_XEN_INFO *) GET_GUID_HOB_DATA (GuidHob);
  51   HyperPage = XenInfo->HyperPages;
  52   return EFI_SUCCESS;
  53 }
  54
  55 UINT64
  56 XenHypercallHvmGetParam (
  57   IN UINT32        Index
  58   )
  59 {
  60   xen_hvm_param_t     Parameter;
  61   INTN                Error;
  62
  63   Parameter.domid = DOMID_SELF;
  64   Parameter.index = Index;
  65   Error = XenHypercall2 (__HYPERVISOR_hvm_op,
  66                          HVMOP_get_param, (INTN) &Parameter);
  67   if (Error != 0) {
  68     DEBUG ((EFI_D_ERROR,
  69             "XenHypercall: Error %d trying to get HVM parameter %d\n",
  70             Error, Index));
  71     return 0;
  72   }
  73   return Parameter.value;
  74 }
  75
  76 INTN
  77 XenHypercallMemoryOp (
  78   IN     UINTN Operation,
  79   IN OUT VOID *Arguments
  80   )
  81 {
  82   return XenHypercall2 (__HYPERVISOR_memory_op,
  83                         Operation, (INTN) Arguments);
  84 }
  85
  86 INTN
  87 XenHypercallEventChannelOp (
  88   IN     INTN Operation,
  89   IN OUT VOID *Arguments
  90   )
  91 {
  92   return XenHypercall2 (__HYPERVISOR_event_channel_op,
  93                         Operation, (INTN) Arguments);
  94 }
  95
  96 INTN
  97 EFIAPI
  98 XenHypercall2 (
  99   IN     UINTN  HypercallID,
 100   IN OUT INTN   Arg1,
 101   IN OUT INTN   Arg2
 102   )
 103 {
 104   ASSERT (HyperPage != NULL);
 105
 106   return __XenHypercall2 ((UINT8*)HyperPage + HypercallID * 32, Arg1, Arg2);
 107 }