1 files changed, 78 insertions, 0 deletions
diff --git a/roms/edk2/OvmfPkg/XenBusDxe/EventChannel.c b/roms/edk2/OvmfPkg/XenBusDxe/EventChannel.c
new file mode 100644
index 000000000..6c905b511
--- /dev/null
+++ b/roms/edk2/OvmfPkg/XenBusDxe/EventChannel.c
@@ -0,0 +1,78 @@
+/** @file
+  Event Channel function implementation.
+
+  Event channel are use to notify of an event that happened in a shared
+  structure for example.
+
+  Copyright (C) 2014, Citrix Ltd.
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#include "EventChannel.h"
+
+#include <Library/XenHypercallLib.h>
+
+UINT32
+XenEventChannelNotify (
+  IN XENBUS_DEVICE *Dev,
+  IN evtchn_port_t Port
+  )
+{
+  INTN ReturnCode;
+  evtchn_send_t Send;
+
+  Send.port = Port;
+  ReturnCode = XenHypercallEventChannelOp (EVTCHNOP_send, &Send);
+  return (UINT32)ReturnCode;
+}
+
+UINT32
+EFIAPI
+XenBusEventChannelAllocate (
+  IN  XENBUS_PROTOCOL *This,
+  IN  domid_t         DomainId,
+  OUT evtchn_port_t   *Port
+  )
+{
+  evtchn_alloc_unbound_t Parameter;
+  UINT32 ReturnCode;
+
+  Parameter.dom = DOMID_SELF;
+  Parameter.remote_dom = DomainId;
+  ReturnCode = (UINT32)XenHypercallEventChannelOp (
+                                   EVTCHNOP_alloc_unbound,
+                                   &Parameter);
+  if (ReturnCode != 0) {
+    DEBUG ((DEBUG_ERROR, "ERROR: alloc_unbound failed with rc=%d", ReturnCode));
+    return ReturnCode;
+  }
+  *Port = Parameter.port;
+  return ReturnCode;
+}
+
+UINT32
+EFIAPI
+XenBusEventChannelNotify (
+  IN XENBUS_PROTOCOL *This,
+  IN evtchn_port_t   Port
+  )
+{
+  XENBUS_PRIVATE_DATA *Private;
+
+  Private = XENBUS_PRIVATE_DATA_FROM_THIS(This);
+  return XenEventChannelNotify (Private->Dev, Port);
+}
+
+UINT32
+EFIAPI
+XenBusEventChannelClose (
+  IN XENBUS_PROTOCOL *This,
+  IN evtchn_port_t   Port
+  )
+{
+  evtchn_close_t Close;
+
+  Close.port = Port;
+  return (UINT32)XenHypercallEventChannelOp (EVTCHNOP_close, &Close);
+}