[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, 129 insertions, 0 deletions

diff --git a/src/drivers/net/efi/snponly.c b/src/drivers/net/efi/snponly.c
new file mode 100644
index 000000000..435ed4fb5
--- /dev/null
+++ b/src/drivers/net/efi/snponly.c
@@ -0,0 +1,129 @@
+/*
+ * 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 <string.h>
+#include <errno.h>
+#include <ipxe/device.h>
+#include <ipxe/init.h>
+#include <ipxe/efi/efi.h>
+#include <ipxe/efi/Protocol/SimpleNetwork.h>
+#include "snp.h"
+#include "snpnet.h"
+
+/** @file
+ *
+ * Chain-loading Simple Network Protocol Bus Driver
+ *
+ * This bus driver allows iPXE to use the EFI Simple Network Protocol provided
+ * by the platform to transmit and receive packets. It attaches to only the
+ * device handle that iPXE was loaded from, that is, it will only use the
+ * Simple Network Protocol on the current loaded image's device handle.
+ *
+ * Eseentially, this driver provides the EFI equivalent of the "undionly"
+ * driver.
+ */
+
+/** The one and only SNP network device */
+static struct snp_device snponly_dev;
+
+/** EFI simple network protocol GUID */
+static EFI_GUID efi_simple_network_protocol_guid
+	= EFI_SIMPLE_NETWORK_PROTOCOL_GUID;
+
+/**
+ * Probe SNP root bus
+ *
+ * @v rootdev		SNP bus root device
+ *
+ * Look at the loaded image's device handle and see if the simple network
+ * protocol exists. If so, register a driver for it.
+ */
+static int snpbus_probe ( struct root_device *rootdev ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	EFI_STATUS efirc;
+	int rc;
+	void *snp;
+
+	efirc = bs->OpenProtocol ( efi_loaded_image->DeviceHandle,
+				   &efi_simple_network_protocol_guid,
+				   &snp, efi_image_handle, NULL,
+				   EFI_OPEN_PROTOCOL_GET_PROTOCOL );
+	if ( efirc ) {
+		DBG ( "Could not find Simple Network Protocol!\n" );
+		return -ENODEV;
+	}
+	snponly_dev.snp = snp;
+
+	/* Add to device hierarchy */
+	strncpy ( snponly_dev.dev.name, "EFI SNP",
+		  ( sizeof ( snponly_dev.dev.name ) - 1 ) );
+	snponly_dev.dev.parent = &rootdev->dev;
+	list_add ( &snponly_dev.dev.siblings, &rootdev->dev.children);
+	INIT_LIST_HEAD ( &snponly_dev.dev.children );
+
+	/* Create network device */
+	if ( ( rc = snpnet_probe ( &snponly_dev ) ) != 0 )
+		goto err;
+
+	return 0;
+
+err:
+	list_del ( &snponly_dev.dev.siblings );
+	return rc;
+}
+
+/**
+ * Remove SNP root bus
+ *
+ * @v rootdev		SNP bus root device
+ */
+static void snpbus_remove ( struct root_device *rootdev __unused ) {
+	snpnet_remove ( &snponly_dev );
+	list_del ( &snponly_dev.dev.siblings );
+}
+
+/** SNP bus root device driver */
+static struct root_driver snp_root_driver = {
+	.probe = snpbus_probe,
+	.remove = snpbus_remove,
+};
+
+/** SNP bus root device */
+struct root_device snp_root_device __root_device = {
+	.dev = { .name = "EFI SNP" },
+	.driver = &snp_root_driver,
+};
+
+/**
+ * Prepare for exit
+ *
+ * @v flags		Shutdown flags
+ */
+static void snponly_shutdown ( int flags ) {
+	/* If we are shutting down to boot an OS, make sure the SNP does not
+	 * stay active.
+	 */
+	if ( flags & SHUTDOWN_BOOT )
+		snponly_dev.removal_state = EfiSimpleNetworkStopped;
+}
+
+struct startup_fn startup_snponly __startup_fn ( STARTUP_LATE ) = {
+	.shutdown = snponly_shutdown,
+};