[efi] Add the "snpnet" driver

Add a new network driver that consumes the EFI Simple Network
Protocol.  Also add a bus driver that can find the Simple Network
Protocol that iPXE was loaded from; the resulting behavior is similar
to the "undionly" driver for BIOS systems.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 362 insertions, 0 deletions

diff --git a/src/drivers/net/efi/snpnet.c b/src/drivers/net/efi/snpnet.c
new file mode 100644
index 00000000..ba63a01d
--- /dev/null
+++ b/src/drivers/net/efi/snpnet.c
@@ -0,0 +1,362 @@
+/*
+ * Copyright (C) 2010 VMware, Inc.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <errno.h>
+#include <string.h>
+#include <ipxe/io.h>
+#include <ipxe/iobuf.h>
+#include <ipxe/netdevice.h>
+#include <ipxe/if_ether.h>
+#include <ipxe/ethernet.h>
+#include <ipxe/efi/efi.h>
+#include <ipxe/efi/Protocol/SimpleNetwork.h>
+#include "snp.h"
+#include "snpnet.h"
+
+/** @file
+ *
+ * SNP network device driver
+ *
+ */
+
+/** SNP net device structure */
+struct snpnet_device {
+	/** The underlying simple network protocol */
+	EFI_SIMPLE_NETWORK_PROTOCOL *snp;
+
+	/** State that the SNP should be in after close */
+	UINT32 close_state;
+};
+
+/**
+ * Transmit packet
+ *
+ * @v netdev		Network device
+ * @v iobuf		I/O buffer
+ * @ret rc		Return status code
+ */
+static int snpnet_transmit ( struct net_device *netdev,
+			     struct io_buffer *iobuf ) {
+	struct snpnet_device *snpnetdev = netdev->priv;
+	EFI_SIMPLE_NETWORK_PROTOCOL *snp = snpnetdev->snp;
+	EFI_STATUS efirc;
+	size_t len = iob_len ( iobuf );
+
+	efirc = snp->Transmit ( snp, 0, len, iobuf->data, NULL, NULL, NULL );
+	return EFIRC_TO_RC ( efirc );
+}
+
+/**
+ * Find a I/O buffer on the list of outstanding Tx buffers and complete it.
+ *
+ * @v snpnetdev		SNP network device
+ * @v txbuf		Buffer address
+ */
+static void snpnet_complete ( struct net_device *netdev, void *txbuf ) {
+	struct io_buffer *tmp;
+	struct io_buffer *iobuf;
+
+	list_for_each_entry_safe ( iobuf, tmp, &netdev->tx_queue, list ) {
+		if ( iobuf->data == txbuf ) {
+			netdev_tx_complete ( netdev, iobuf );
+			break;
+		}
+	}
+}
+
+/**
+ * Poll for received packets
+ *
+ * @v netdev		Network device
+ */
+static void snpnet_poll ( struct net_device *netdev ) {
+	struct snpnet_device *snpnetdev = netdev->priv;
+	EFI_SIMPLE_NETWORK_PROTOCOL *snp = snpnetdev->snp;
+	EFI_STATUS efirc;
+	struct io_buffer *iobuf = NULL;
+	UINTN len;
+	void *txbuf;
+
+	/* Process Tx completions */
+	while ( 1 ) {
+		efirc = snp->GetStatus ( snp, NULL, &txbuf );
+		if ( efirc ) {
+			DBGC ( snp, "SNP %p could not get status %s\n", snp,
+			       efi_strerror ( efirc ) );
+			break;
+		}
+
+		if ( txbuf == NULL )
+			break;
+
+		snpnet_complete ( netdev, txbuf );
+	}
+
+	/* Process received packets */
+	while ( 1 ) {
+		/* The spec is not clear if the max packet size refers to the
+		 * payload or the entire packet including headers. The Receive
+		 * function needs a buffer large enough to contain the headers,
+		 * and potentially a 4-byte CRC and 4-byte VLAN tag (?), so add
+		 * some breathing room.
+		 */
+		len = snp->Mode->MaxPacketSize + ETH_HLEN + 8;
+		iobuf = alloc_iob ( len );
+		if ( iobuf == NULL ) {
+			netdev_rx_err ( netdev, NULL, -ENOMEM );
+			break;
+		}
+
+		efirc = snp->Receive ( snp, NULL, &len, iobuf->data,
+				       NULL, NULL, NULL );
+
+		/* No packets left? */
+		if ( efirc == EFI_NOT_READY ) {
+			free_iob ( iobuf );
+			break;
+		}
+
+		/* Other error? */
+		if ( efirc ) {
+			DBGC ( snp, "SNP %p receive packet error: %s "
+				    "(len was %zd, is now %zd)\n",
+			       snp, efi_strerror ( efirc ), iob_len(iobuf),
+			       (size_t)len );
+			netdev_rx_err ( netdev, iobuf, efirc );
+			break;
+		}
+
+		/* Packet is valid, deliver it */
+		iob_put ( iobuf, len );
+		netdev_rx ( netdev, iob_disown ( iobuf ) );
+	}
+}
+
+/**
+ * Open NIC
+ *
+ * @v netdev		Net device
+ * @ret rc		Return status code
+ */
+static int snpnet_open ( struct net_device *netdev ) {
+	struct snpnet_device *snpnetdev = netdev->priv;
+	EFI_SIMPLE_NETWORK_PROTOCOL *snp = snpnetdev->snp;
+	EFI_STATUS efirc;
+	UINT32 enableFlags, disableFlags;
+
+	snpnetdev->close_state = snp->Mode->State;
+	if ( snp->Mode->State != EfiSimpleNetworkInitialized ) {
+		efirc = snp->Initialize ( snp, 0, 0 );
+		if ( efirc ) {
+			DBGC ( snp, "SNP %p could not initialize: %s\n",
+			       snp, efi_strerror ( efirc ) );
+			return EFIRC_TO_RC ( efirc );
+		}
+	}
+
+        /* Use the default MAC address */
+	efirc = snp->StationAddress ( snp, FALSE,
+				      (EFI_MAC_ADDRESS *)netdev->ll_addr );
+	if ( efirc ) {
+		DBGC ( snp, "SNP %p could not reset station address: %s\n",
+		       snp, efi_strerror ( efirc ) );
+	}
+
+	/* Set up receive filters to receive unicast and broadcast packets
+	 * always. Also, enable either promiscuous multicast (if possible) or
+	 * promiscuous operation, in order to catch all multicast packets.
+	 */
+	enableFlags = snp->Mode->ReceiveFilterMask &
+		      ( EFI_SIMPLE_NETWORK_RECEIVE_UNICAST |
+			EFI_SIMPLE_NETWORK_RECEIVE_BROADCAST );
+	disableFlags = snp->Mode->ReceiveFilterMask &
+		       ( EFI_SIMPLE_NETWORK_RECEIVE_MULTICAST |
+			 EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS |
+			 EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS_MULTICAST );
+	if ( snp->Mode->ReceiveFilterMask &
+	     EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS_MULTICAST ) {
+		enableFlags |= EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS_MULTICAST;
+	} else if ( snp->Mode->ReceiveFilterMask &
+		    EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS ) {
+		enableFlags |= EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS;
+	}
+	disableFlags &= ~enableFlags;
+	efirc = snp->ReceiveFilters ( snp, enableFlags, disableFlags,
+				      FALSE, 0, NULL );
+	if ( efirc ) {
+		DBGC ( snp, "SNP %p could not set receive filters: %s\n",
+		       snp, efi_strerror ( efirc ) );
+	}
+
+	DBGC ( snp, "SNP %p opened\n", snp );
+	return 0;
+}
+
+/**
+ * Close NIC
+ *
+ * @v netdev		Net device
+ */
+static void snpnet_close ( struct net_device *netdev ) {
+	struct snpnet_device *snpnetdev = netdev->priv;
+	EFI_SIMPLE_NETWORK_PROTOCOL *snp = snpnetdev->snp;
+	EFI_STATUS efirc;
+
+	if ( snpnetdev->close_state != EfiSimpleNetworkInitialized ) {
+		efirc = snp->Shutdown ( snp );
+		if ( efirc ) {
+			DBGC ( snp, "SNP %p could not shut down: %s\n",
+			       snp, efi_strerror ( efirc ) );
+		}
+	}
+}
+
+/**
+ * Enable/disable interrupts
+ *
+ * @v netdev		Net device
+ * @v enable		Interrupts should be enabled
+ */
+static void snpnet_irq ( struct net_device *netdev, int enable ) {
+	struct snpnet_device *snpnetdev = netdev->priv;
+	EFI_SIMPLE_NETWORK_PROTOCOL *snp = snpnetdev->snp;
+
+	/* On EFI, interrupts are never necessary. (This function is only
+	 * required for BIOS PXE.) If interrupts were required, they could be
+	 * simulated using a fast timer.
+	 */
+	DBGC ( snp, "SNP %p cannot %s interrupts\n",
+	       snp, ( enable ? "enable" : "disable" ) );
+}
+
+/** SNP network device operations */
+static struct net_device_operations snpnet_operations = {
+	.open		= snpnet_open,
+	.close		= snpnet_close,
+	.transmit	= snpnet_transmit,
+	.poll		= snpnet_poll,
+	.irq   		= snpnet_irq,
+};
+
+/**
+ * Probe SNP device
+ *
+ * @v snpdev		SNP device
+ * @ret rc		Return status code
+ */
+int snpnet_probe ( struct snp_device *snpdev ) {
+	EFI_SIMPLE_NETWORK_PROTOCOL *snp = snpdev->snp;
+	EFI_STATUS efirc;
+	struct net_device *netdev;
+	struct snpnet_device *snpnetdev;
+	int rc;
+
+	DBGC ( snp, "SNP %p probing...\n", snp );
+
+	/* Allocate net device */
+	netdev = alloc_etherdev ( sizeof ( struct snpnet_device ) );
+	if ( ! netdev )
+		return -ENOMEM;
+	netdev_init ( netdev, &snpnet_operations );
+	netdev->dev = &snpdev->dev;
+	snpdev->netdev = netdev;
+	snpnetdev = netdev->priv;
+	snpnetdev->snp = snp;
+	snpdev->removal_state = snp->Mode->State;
+
+	/* Start the interface */
+	if ( snp->Mode->State == EfiSimpleNetworkStopped ) {
+		efirc = snp->Start ( snp );
+		if ( efirc ) {
+			DBGC ( snp, "SNP %p could not start: %s\n", snp,
+			       efi_strerror ( efirc ) );
+			rc = EFIRC_TO_RC ( efirc );
+			goto err_start;
+		}
+	}
+
+	if ( snp->Mode->HwAddressSize > sizeof ( netdev->hw_addr ) ) {
+		DBGC ( snp, "SNP %p hardware address is too large\n", snp );
+		rc = -EINVAL;
+		goto err_hwaddr;
+	}
+	memcpy ( netdev->hw_addr, snp->Mode->PermanentAddress.Addr,
+		 snp->Mode->HwAddressSize );
+
+	/* Mark as link up; we don't handle link state */
+	netdev_link_up ( netdev );
+
+	/* Register network device */
+	if ( ( rc = register_netdev ( netdev ) ) != 0 )
+		goto err_register;
+
+	DBGC ( snp, "SNP %p added\n", snp );
+	return 0;
+
+err_register:
+err_hwaddr:
+	if ( snpdev->removal_state == EfiSimpleNetworkStopped )
+		snp->Stop ( snp );
+
+err_start:
+	netdev_nullify ( netdev );
+	netdev_put ( netdev );
+	snpdev->netdev = NULL;
+	return rc;
+}
+
+/**
+ * Remove SNP device
+ *
+ * @v snpdev		SNP device
+ */
+void snpnet_remove ( struct snp_device *snpdev ) {
+	EFI_SIMPLE_NETWORK_PROTOCOL *snp = snpdev->snp;
+	EFI_STATUS efirc;
+	struct net_device *netdev = snpdev->netdev;
+
+	if ( snp->Mode->State == EfiSimpleNetworkInitialized &&
+	     snpdev->removal_state != EfiSimpleNetworkInitialized ) {
+		DBGC ( snp, "SNP %p shutting down\n", snp );
+		efirc = snp->Shutdown ( snp );
+		if ( efirc ) {
+			DBGC ( snp, "SNP %p could not shut down: %s\n",
+			       snp, efi_strerror ( efirc ) );
+		}
+	}
+
+	if ( snp->Mode->State == EfiSimpleNetworkStarted &&
+	     snpdev->removal_state == EfiSimpleNetworkStopped ) {
+		DBGC ( snp, "SNP %p stopping\n", snp );
+		efirc = snp->Stop ( snp );
+		if ( efirc ) {
+			DBGC ( snp, "SNP %p could not be stopped\n", snp );
+		}
+	}
+
+	/* Unregister net device */
+	unregister_netdev ( netdev );
+
+	/* Free network device */
+	netdev_nullify ( netdev );
+	netdev_put ( netdev );
+
+	DBGC ( snp, "SNP %p removed\n", snp );
+}