diff options
Diffstat (limited to 'OvmfPkg/VirtioNetDxe/SnpGetStatus.c')
| -rw-r--r-- | OvmfPkg/VirtioNetDxe/SnpGetStatus.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/OvmfPkg/VirtioNetDxe/SnpGetStatus.c b/OvmfPkg/VirtioNetDxe/SnpGetStatus.c new file mode 100644 index 0000000000..ce6a7295fe --- /dev/null +++ b/OvmfPkg/VirtioNetDxe/SnpGetStatus.c @@ -0,0 +1,158 @@ +/** @file
+
+ Implementation of the SNP.GetStatus() function and its private helpers if
+ any.
+
+ Copyright (C) 2013, Red Hat, Inc.
+ Copyright (c) 2006 - 2010, 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"
+
+/**
+ Reads the current interrupt status and recycled transmit buffer status from
+ a network interface.
+
+ @param This The protocol instance pointer.
+ @param InterruptStatus A pointer to the bit mask of the currently active
+ interrupts If this is NULL, the interrupt status will
+ not be read from the device. If this is not NULL, the
+ interrupt status will be read from the device. When
+ the interrupt status is read, it will also be
+ cleared. Clearing the transmit interrupt does not
+ empty the recycled transmit buffer array.
+ @param TxBuf Recycled transmit buffer address. The network
+ interface will not transmit if its internal recycled
+ transmit buffer array is full. Reading the transmit
+ buffer does not clear the transmit interrupt. If this
+ is NULL, then the transmit buffer status will not be
+ read. If there are no transmit buffers to recycle and
+ TxBuf is not NULL, * TxBuf will be set to NULL.
+
+ @retval EFI_SUCCESS The status of the network interface was
+ retrieved.
+ @retval EFI_NOT_STARTED The network interface has not been started.
+ @retval EFI_INVALID_PARAMETER One or more of the parameters has an
+ unsupported value.
+ @retval EFI_DEVICE_ERROR The command could not be sent to the network
+ interface.
+ @retval EFI_UNSUPPORTED This function is not supported by the network
+ interface.
+
+**/
+
+EFI_STATUS
+EFIAPI
+VirtioNetGetStatus (
+ IN EFI_SIMPLE_NETWORK_PROTOCOL *This,
+ OUT UINT32 *InterruptStatus OPTIONAL,
+ OUT VOID **TxBuf OPTIONAL
+ )
+{
+ VNET_DEV *Dev;
+ EFI_TPL OldTpl;
+ EFI_STATUS Status;
+ UINT16 RxCurUsed;
+ UINT16 TxCurUsed;
+
+ if (This == NULL) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Dev = VIRTIO_NET_FROM_SNP (This);
+ OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
+ switch (Dev->Snm.State) {
+ case EfiSimpleNetworkStopped:
+ Status = EFI_NOT_STARTED;
+ goto Exit;
+ case EfiSimpleNetworkStarted:
+ Status = EFI_DEVICE_ERROR;
+ goto Exit;
+ default:
+ break;
+ }
+
+ //
+ // update link status
+ //
+ if (Dev->Snm.MediaPresentSupported) {
+ UINT16 LinkStatus;
+
+ Status = VIRTIO_CFG_READ (Dev, VhdrLinkStatus, &LinkStatus);
+ if (EFI_ERROR (Status)) {
+ goto Exit;
+ }
+ Dev->Snm.MediaPresent = !!(LinkStatus & VIRTIO_NET_S_LINK_UP);
+ }
+
+ //
+ // virtio-0.9.5, 2.4.2 Receiving Used Buffers From the Device
+ //
+ MemoryFence ();
+ RxCurUsed = *Dev->RxRing.Used.Idx;
+ TxCurUsed = *Dev->TxRing.Used.Idx;
+
+ if (InterruptStatus != NULL) {
+ //
+ // report the receive interrupt if there is data available for reception,
+ // report the transmit interrupt if we have transmitted at least one buffer
+ //
+ *InterruptStatus = 0;
+ if (Dev->RxLastUsed != RxCurUsed) {
+ *InterruptStatus |= EFI_SIMPLE_NETWORK_RECEIVE_INTERRUPT;
+ }
+ if (Dev->TxLastUsed != TxCurUsed) {
+ ASSERT (Dev->TxCurPending > 0);
+ *InterruptStatus |= EFI_SIMPLE_NETWORK_TRANSMIT_INTERRUPT;
+ }
+ }
+
+ if (TxBuf != NULL) {
+ if (Dev->TxLastUsed == TxCurUsed) {
+ *TxBuf = NULL;
+ }
+ else {
+ UINT16 UsedElemIdx;
+ UINT32 DescIdx;
+
+ //
+ // fetch the first descriptor among those that the hypervisor reports
+ // completed
+ //
+ ASSERT (Dev->TxCurPending > 0);
+ ASSERT (Dev->TxCurPending <= Dev->TxMaxPending);
+
+ UsedElemIdx = Dev->TxLastUsed++ % Dev->TxRing.QueueSize;
+ DescIdx = Dev->TxRing.Used.UsedElem[UsedElemIdx].Id;
+ ASSERT (DescIdx < 2 * Dev->TxMaxPending - 1);
+
+ //
+ // report buffer address to caller that has been enqueued by caller
+ //
+ *TxBuf = (VOID *) Dev->TxRing.Desc[DescIdx + 1].Addr;
+
+ //
+ // now this descriptor can be used again to enqueue a transmit buffer
+ //
+ Dev->TxFreeStack[--Dev->TxCurPending] = (UINT16) DescIdx;
+ }
+ }
+
+ Status = EFI_SUCCESS;
+
+Exit:
+ gBS->RestoreTPL (OldTpl);
+ return Status;
+}
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