audk/OvmfPkg/VirtioNetDxe/Events.c

91 lines
2.3 KiB
C

/** @file
Implements
- the SNM.WaitForPacket EVT_NOTIFY_WAIT event,
- the EVT_SIGNAL_EXIT_BOOT_SERVICES event
for the virtio-net driver.
Copyright (C) 2013, Red Hat, Inc.
Copyright (c) 2006 - 2012, Intel Corporation. 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.
**/
#include <Library/BaseLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include "VirtioNet.h"
/**
Invoke a notification event
@param Event Event whose notification function is being
invoked.
@param Context The pointer to the notification function's
context, which is implementation-dependent.
**/
VOID
EFIAPI
VirtioNetIsPacketAvailable (
IN EFI_EVENT Event,
IN VOID *Context
)
{
//
// This callback has been enqueued by an external application and is
// running at TPL_CALLBACK already.
//
// The WaitForPacket logic is similar to that of WaitForKey. The former has
// almost no documentation in either the UEFI-2.3.1+errC spec or the
// DWG-2.3.1, but WaitForKey does have some.
//
VNET_DEV *Dev;
UINT16 RxCurUsed;
Dev = Context;
if (Dev->Snm.State != EfiSimpleNetworkInitialized) {
return;
}
//
// virtio-0.9.5, 2.4.2 Receiving Used Buffers From the Device
//
MemoryFence ();
RxCurUsed = *Dev->RxRing.Used.Idx;
if (Dev->RxLastUsed != RxCurUsed) {
gBS->SignalEvent (&Dev->Snp.WaitForPacket);
}
}
VOID
EFIAPI
VirtioNetExitBoot (
IN EFI_EVENT Event,
IN VOID *Context
)
{
//
// This callback has been enqueued by ExitBootServices() and is running at
// TPL_CALLBACK already.
//
// Shut down pending transfers according to DWG-2.3.1, "25.5.1 Exit Boot
// Services Event".
//
VNET_DEV *Dev;
Dev = Context;
if (Dev->Snm.State == EfiSimpleNetworkInitialized) {
VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, 0);
}
}