Add qemu 2.4.0

Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>

6 files changed, 2019 insertions, 0 deletions

diff --git a/qemu/roms/ipxe/src/drivers/net/efi/nii.c b/qemu/roms/ipxe/src/drivers/net/efi/nii.c
new file mode 100644
index 000000000..d0d7da95a
--- /dev/null
+++ b/qemu/roms/ipxe/src/drivers/net/efi/nii.c
@@ -0,0 +1,1101 @@
+/*
+ * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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 Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+#include <errno.h>
+#include <ipxe/netdevice.h>
+#include <ipxe/ethernet.h>
+#include <ipxe/umalloc.h>
+#include <ipxe/efi/efi.h>
+#include <ipxe/efi/efi_driver.h>
+#include <ipxe/efi/efi_pci.h>
+#include <ipxe/efi/efi_utils.h>
+#include <ipxe/efi/Protocol/NetworkInterfaceIdentifier.h>
+#include <ipxe/efi/IndustryStandard/Acpi10.h>
+#include "nii.h"
+
+/** @file
+ *
+ * NII driver
+ *
+ */
+
+/* Error numbers generated by NII */
+#define EIO_INVALID_CDB __einfo_error ( EINFO_EIO_INVALID_CDB )
+#define EINFO_EIO_INVALID_CDB						      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_INVALID_CDB,		      \
+			  "Invalid CDB" )
+#define EIO_INVALID_CPB __einfo_error ( EINFO_EIO_INVALID_CPB )
+#define EINFO_EIO_INVALID_CPB						      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_INVALID_CPB,		      \
+			  "Invalid CPB" )
+#define EIO_BUSY __einfo_error ( EINFO_EIO_BUSY )
+#define EINFO_EIO_BUSY							      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_BUSY,			      \
+			  "Busy" )
+#define EIO_QUEUE_FULL __einfo_error ( EINFO_EIO_QUEUE_FULL )
+#define EINFO_EIO_QUEUE_FULL						      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_QUEUE_FULL,		      \
+			  "Queue full" )
+#define EIO_ALREADY_STARTED __einfo_error ( EINFO_EIO_ALREADY_STARTED )
+#define EINFO_EIO_ALREADY_STARTED					      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_ALREADY_STARTED,	      \
+			  "Already started" )
+#define EIO_NOT_STARTED __einfo_error ( EINFO_EIO_NOT_STARTED )
+#define EINFO_EIO_NOT_STARTED						      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_NOT_STARTED,		      \
+			  "Not started" )
+#define EIO_NOT_SHUTDOWN __einfo_error ( EINFO_EIO_NOT_SHUTDOWN )
+#define EINFO_EIO_NOT_SHUTDOWN						      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_NOT_SHUTDOWN,		      \
+			  "Not shutdown" )
+#define EIO_ALREADY_INITIALIZED __einfo_error ( EINFO_EIO_ALREADY_INITIALIZED )
+#define EINFO_EIO_ALREADY_INITIALIZED					      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_ALREADY_INITIALIZED,	      \
+			  "Already initialized" )
+#define EIO_NOT_INITIALIZED __einfo_error ( EINFO_EIO_NOT_INITIALIZED )
+#define EINFO_EIO_NOT_INITIALIZED					      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_NOT_INITIALIZED,	      \
+			  "Not initialized" )
+#define EIO_DEVICE_FAILURE __einfo_error ( EINFO_EIO_DEVICE_FAILURE )
+#define EINFO_EIO_DEVICE_FAILURE					      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_DEVICE_FAILURE,	      \
+			  "Device failure" )
+#define EIO_NVDATA_FAILURE __einfo_error ( EINFO_EIO_NVDATA_FAILURE )
+#define EINFO_EIO_NVDATA_FAILURE					      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_NVDATA_FAILURE,	      \
+			  "Non-volatile data failure" )
+#define EIO_UNSUPPORTED __einfo_error ( EINFO_EIO_UNSUPPORTED )
+#define EINFO_EIO_UNSUPPORTED						      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_UNSUPPORTED,		      \
+			  "Unsupported" )
+#define EIO_BUFFER_FULL __einfo_error ( EINFO_EIO_BUFFER_FULL )
+#define EINFO_EIO_BUFFER_FULL						      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_BUFFER_FULL,		      \
+			  "Buffer full" )
+#define EIO_INVALID_PARAMETER __einfo_error ( EINFO_EIO_INVALID_PARAMETER )
+#define EINFO_EIO_INVALID_PARAMETER					      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_INVALID_PARAMETER,	      \
+			  "Invalid parameter" )
+#define EIO_INVALID_UNDI __einfo_error ( EINFO_EIO_INVALID_UNDI )
+#define EINFO_EIO_INVALID_UNDI						      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_INVALID_UNDI,		      \
+			  "Invalid UNDI" )
+#define EIO_IPV4_NOT_SUPPORTED __einfo_error ( EINFO_EIO_IPV4_NOT_SUPPORTED )
+#define EINFO_EIO_IPV4_NOT_SUPPORTED					      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_IPV4_NOT_SUPPORTED,	      \
+			  "IPv4 not supported" )
+#define EIO_IPV6_NOT_SUPPORTED __einfo_error ( EINFO_EIO_IPV6_NOT_SUPPORTED )
+#define EINFO_EIO_IPV6_NOT_SUPPORTED					      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_IPV6_NOT_SUPPORTED,	      \
+			  "IPv6 not supported" )
+#define EIO_NOT_ENOUGH_MEMORY __einfo_error ( EINFO_EIO_NOT_ENOUGH_MEMORY )
+#define EINFO_EIO_NOT_ENOUGH_MEMORY					      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_NOT_ENOUGH_MEMORY,	      \
+			  "Not enough memory" )
+#define EIO_NO_DATA __einfo_error ( EINFO_EIO_NO_DATA )
+#define EINFO_EIO_NO_DATA						      \
+	__einfo_uniqify ( EINFO_EIO, PXE_STATCODE_NO_DATA,		      \
+			  "No data" )
+#define EIO_STAT( stat )						      \
+	EUNIQ ( EINFO_EIO, -(stat), EIO_INVALID_CDB, EIO_INVALID_CPB,	      \
+		EIO_BUSY, EIO_QUEUE_FULL, EIO_ALREADY_STARTED,		      \
+		EIO_NOT_STARTED, EIO_NOT_SHUTDOWN, EIO_ALREADY_INITIALIZED,   \
+		EIO_NOT_INITIALIZED, EIO_DEVICE_FAILURE, EIO_NVDATA_FAILURE,  \
+		EIO_UNSUPPORTED, EIO_BUFFER_FULL, EIO_INVALID_PARAMETER,      \
+		EIO_INVALID_UNDI, EIO_IPV4_NOT_SUPPORTED,		      \
+		EIO_IPV6_NOT_SUPPORTED, EIO_NOT_ENOUGH_MEMORY, EIO_NO_DATA )
+
+/** Maximum PCI BAR
+ *
+ * This is defined in <ipxe/efi/IndustryStandard/Pci22.h>, but we
+ * can't #include that since it collides with <ipxe/pci.h>.
+ */
+#define PCI_MAX_BAR 6
+
+/** An NII NIC */
+struct nii_nic {
+	/** EFI device */
+	struct efi_device *efidev;
+	/** Network interface identifier protocol */
+	EFI_NETWORK_INTERFACE_IDENTIFIER_PROTOCOL *nii;
+	/** !PXE structure */
+	PXE_SW_UNDI *undi;
+	/** Entry point */
+	EFIAPI VOID ( * issue ) ( UINT64 cdb );
+	/** Generic device */
+	struct device dev;
+
+	/** PCI device */
+	EFI_HANDLE pci_device;
+	/** PCI I/O protocol */
+	EFI_PCI_IO_PROTOCOL *pci_io;
+	/** Memory BAR */
+	unsigned int mem_bar;
+	/** I/O BAR */
+	unsigned int io_bar;
+
+	/** Broadcast address */
+	PXE_MAC_ADDR broadcast;
+	/** Maximum packet length */
+	size_t mtu;
+
+	/** Hardware transmit/receive buffer */
+	userptr_t buffer;
+	/** Hardware transmit/receive buffer length */
+	size_t buffer_len;
+
+	/** Saved task priority level */
+	EFI_TPL saved_tpl;
+
+	/** Current transmit buffer */
+	struct io_buffer *txbuf;
+	/** Current receive buffer */
+	struct io_buffer *rxbuf;
+};
+
+/** Maximum number of received packets per poll */
+#define NII_RX_QUOTA 4
+
+/**
+ * Open PCI I/O protocol and identify BARs
+ *
+ * @v nii		NII NIC
+ * @ret rc		Return status code
+ */
+static int nii_pci_open ( struct nii_nic *nii ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	EFI_HANDLE device = nii->efidev->device;
+	EFI_HANDLE pci_device;
+	union {
+		EFI_PCI_IO_PROTOCOL *pci_io;
+		void *interface;
+	} pci_io;
+	union {
+		EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *acpi;
+		void *resource;
+	} desc;
+	unsigned int bar;
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Locate PCI I/O protocol */
+	if ( ( rc = efi_locate_device ( device, &efi_pci_io_protocol_guid,
+					&pci_device ) ) != 0 ) {
+		DBGC ( nii, "NII %s could not locate PCI I/O protocol: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		goto err_locate;
+	}
+	nii->pci_device = pci_device;
+
+	/* Open PCI I/O protocol */
+	if ( ( efirc = bs->OpenProtocol ( pci_device, &efi_pci_io_protocol_guid,
+					  &pci_io.interface, efi_image_handle,
+					  device,
+					  EFI_OPEN_PROTOCOL_GET_PROTOCOL ))!=0){
+		rc = -EEFI ( efirc );
+		DBGC ( nii, "NII %s could not open PCI I/O protocol: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		goto err_open;
+	}
+	nii->pci_io = pci_io.pci_io;
+
+	/* Identify memory and I/O BARs */
+	nii->mem_bar = PCI_MAX_BAR;
+	nii->io_bar = PCI_MAX_BAR;
+	for ( bar = 0 ; bar < PCI_MAX_BAR ; bar++ ) {
+		efirc = nii->pci_io->GetBarAttributes ( nii->pci_io, bar, NULL,
+							&desc.resource );
+		if ( efirc == EFI_UNSUPPORTED ) {
+			/* BAR not present; ignore */
+			continue;
+		}
+		if ( efirc != 0 ) {
+			rc = -EEFI ( efirc );
+			DBGC ( nii, "NII %s could not get BAR %d attributes: "
+			       "%s\n", nii->dev.name, bar, strerror ( rc ) );
+			goto err_get_bar_attributes;
+		}
+		if ( desc.acpi->ResType == ACPI_ADDRESS_SPACE_TYPE_MEM ) {
+			nii->mem_bar = bar;
+		} else if ( desc.acpi->ResType == ACPI_ADDRESS_SPACE_TYPE_IO ) {
+			nii->io_bar = bar;
+		}
+		bs->FreePool ( desc.resource );
+	}
+	DBGC ( nii, "NII %s has ", nii->dev.name );
+	if ( nii->mem_bar < PCI_MAX_BAR ) {
+		DBGC ( nii, "memory BAR %d and ", nii->mem_bar );
+	} else {
+		DBGC ( nii, "no memory BAR and " );
+	}
+	if ( nii->io_bar < PCI_MAX_BAR ) {
+		DBGC ( nii, "I/O BAR %d\n", nii->io_bar );
+	} else {
+		DBGC ( nii, "no I/O BAR\n" );
+	}
+
+	return 0;
+
+ err_get_bar_attributes:
+	bs->CloseProtocol ( pci_device, &efi_pci_io_protocol_guid,
+			    efi_image_handle, device );
+ err_open:
+ err_locate:
+	return rc;
+}
+
+/**
+ * Close PCI I/O protocol
+ *
+ * @v nii		NII NIC
+ * @ret rc		Return status code
+ */
+static void nii_pci_close ( struct nii_nic *nii ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+
+	bs->CloseProtocol ( nii->pci_device, &efi_pci_io_protocol_guid,
+			    efi_image_handle, nii->efidev->device );
+}
+
+/**
+ * I/O callback
+ *
+ * @v unique_id		NII NIC
+ * @v op		Operations
+ * @v len		Length of data
+ * @v addr		Address
+ * @v data		Data buffer
+ */
+static EFIAPI VOID nii_io ( UINT64 unique_id, UINT8 op, UINT8 len, UINT64 addr,
+			    UINT64 data ) {
+	struct nii_nic *nii = ( ( void * ) ( intptr_t ) unique_id );
+	EFI_PCI_IO_PROTOCOL_ACCESS *access;
+	EFI_PCI_IO_PROTOCOL_IO_MEM io;
+	EFI_PCI_IO_PROTOCOL_WIDTH width;
+	unsigned int bar;
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Determine accessor and BAR */
+	if ( op & ( PXE_MEM_READ | PXE_MEM_WRITE ) ) {
+		access = &nii->pci_io->Mem;
+		bar = nii->mem_bar;
+	} else {
+		access = &nii->pci_io->Io;
+		bar = nii->io_bar;
+	}
+
+	/* Determine operaton */
+	io = ( ( op & ( PXE_IO_WRITE | PXE_MEM_WRITE ) ) ?
+	       access->Write : access->Read );
+
+	/* Determine width */
+	width = ( fls ( len ) - 1 );
+
+	/* Issue operation */
+	if ( ( efirc = io ( nii->pci_io, width, bar, addr, 1,
+			    ( ( void * ) ( intptr_t ) data ) ) ) != 0 ) {
+		rc = -EEFI ( efirc );
+		DBGC ( nii, "NII %s I/O operation %#x failed: %s\n",
+		       nii->dev.name, op, strerror ( rc ) );
+		/* No way to report failure */
+		return;
+	}
+}
+
+/**
+ * Delay callback
+ *
+ * @v unique_id		NII NIC
+ * @v microseconds	Delay in microseconds
+ */
+static EFIAPI VOID nii_delay ( UINT64 unique_id __unused, UINTN microseconds ) {
+
+	udelay ( microseconds );
+}
+
+/**
+ * Block callback
+ *
+ * @v unique_id		NII NIC
+ * @v acquire		Acquire lock
+ */
+static EFIAPI VOID nii_block ( UINT64 unique_id, UINT32 acquire ) {
+	struct nii_nic *nii = ( ( void * ) ( intptr_t ) unique_id );
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+
+	/* This functionality (which is copied verbatim from the
+	 * SnpDxe implementation of this function) appears to be
+	 * totally brain-dead, since it produces no actual blocking
+	 * behaviour.
+	 */
+	if ( acquire ) {
+		nii->saved_tpl = bs->RaiseTPL ( TPL_NOTIFY );
+	} else {
+		bs->RestoreTPL ( nii->saved_tpl );
+	}
+}
+
+/**
+ * Construct operation from opcode and flags
+ *
+ * @v opcode		Opcode
+ * @v opflags		Flags
+ * @ret op		Operation
+ */
+#define NII_OP( opcode, opflags ) ( (opcode) | ( (opflags) << 16 ) )
+
+/**
+ * Extract opcode from operation
+ *
+ * @v op		Operation
+ * @ret opcode		Opcode
+ */
+#define NII_OPCODE( op ) ( (op) & 0xffff )
+
+/**
+ * Extract flags from operation
+ *
+ * @v op		Operation
+ * @ret opflags		Flags
+ */
+#define NII_OPFLAGS( op ) ( (op) >> 16 )
+
+/**
+ * Issue command with parameter block and data block
+ *
+ * @v nii		NII NIC
+ * @v op		Operation
+ * @v cpb		Command parameter block, or NULL
+ * @v cpb_len		Command parameter block length
+ * @v db		Data block, or NULL
+ * @v db_len		Data block length
+ * @ret stat		Status flags, or negative status code
+ */
+static int nii_issue_cpb_db ( struct nii_nic *nii, unsigned int op, void *cpb,
+			      size_t cpb_len, void *db, size_t db_len ) {
+	PXE_CDB cdb;
+
+	/* Prepare command descriptor block */
+	memset ( &cdb, 0, sizeof ( cdb ) );
+	cdb.OpCode = NII_OPCODE ( op );
+	cdb.OpFlags = NII_OPFLAGS ( op );
+	cdb.CPBaddr = ( ( intptr_t ) cpb );
+	cdb.CPBsize = cpb_len;
+	cdb.DBaddr = ( ( intptr_t ) db );
+	cdb.DBsize = db_len;
+	cdb.IFnum = nii->nii->IfNum;
+
+	/* Issue command */
+	nii->issue ( ( intptr_t ) &cdb );
+
+	/* Check completion status */
+	if ( cdb.StatCode != PXE_STATCODE_SUCCESS )
+		return -cdb.StatCode;
+
+	/* Return command-specific status flags */
+	return ( cdb.StatFlags & ~PXE_STATFLAGS_STATUS_MASK );
+}
+
+/**
+ * Issue command with parameter block
+ *
+ * @v nii		NII NIC
+ * @v op		Operation
+ * @v cpb		Command parameter block, or NULL
+ * @v cpb_len		Command parameter block length
+ * @ret stat		Status flags, or negative status code
+ */
+static int nii_issue_cpb ( struct nii_nic *nii, unsigned int op, void *cpb,
+			   size_t cpb_len ) {
+
+	return nii_issue_cpb_db ( nii, op, cpb, cpb_len, NULL, 0 );
+}
+
+/**
+ * Issue command with data block
+ *
+ * @v nii		NII NIC
+ * @v op		Operation
+ * @v db		Data block, or NULL
+ * @v db_len		Data block length
+ * @ret stat		Status flags, or negative status code
+ */
+static int nii_issue_db ( struct nii_nic *nii, unsigned int op, void *db,
+			  size_t db_len ) {
+
+	return nii_issue_cpb_db ( nii, op, NULL, 0, db, db_len );
+}
+
+/**
+ * Issue command
+ *
+ *
+ * @v nii		NII NIC
+ * @v op		Operation
+ * @ret stat		Status flags, or negative status code
+ */
+static int nii_issue ( struct nii_nic *nii, unsigned int op ) {
+
+	return nii_issue_cpb_db ( nii, op, NULL, 0, NULL, 0 );
+}
+
+/**
+ * Start UNDI
+ *
+ * @v nii		NII NIC
+ * @ret rc		Return status code
+ */
+static int nii_start_undi ( struct nii_nic *nii ) {
+	PXE_CPB_START_31 cpb;
+	int stat;
+	int rc;
+
+	/* Construct parameter block */
+	memset ( &cpb, 0, sizeof ( cpb ) );
+	cpb.Delay = ( ( intptr_t ) nii_delay );
+	cpb.Block = ( ( intptr_t ) nii_block );
+	cpb.Mem_IO = ( ( intptr_t ) nii_io );
+	cpb.Unique_ID = ( ( intptr_t ) nii );
+
+	/* Issue command */
+	if ( ( stat = nii_issue_cpb ( nii, PXE_OPCODE_START, &cpb,
+				      sizeof ( cpb ) ) ) < 0 ) {
+		rc = -EIO_STAT ( stat );
+		DBGC ( nii, "NII %s could not start: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * Stop UNDI
+ *
+ * @v nii		NII NIC
+ */
+static void nii_stop_undi ( struct nii_nic *nii ) {
+	int stat;
+	int rc;
+
+	/* Issue command */
+	if ( ( stat = nii_issue ( nii, PXE_OPCODE_STOP ) ) < 0 ) {
+		rc = -EIO_STAT ( stat );
+		DBGC ( nii, "NII %s could not stop: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		/* Nothing we can do about it */
+		return;
+	}
+}
+
+/**
+ * Get initialisation information
+ *
+ * @v nii		NII NIC
+ * @v netdev		Network device to fill in
+ * @ret rc		Return status code
+ */
+static int nii_get_init_info ( struct nii_nic *nii,
+			       struct net_device *netdev ) {
+	PXE_DB_GET_INIT_INFO db;
+	int stat;
+	int rc;
+
+	/* Issue command */
+	if ( ( stat = nii_issue_db ( nii, PXE_OPCODE_GET_INIT_INFO, &db,
+				     sizeof ( db ) ) ) < 0 ) {
+		rc = -EIO_STAT ( stat );
+		DBGC ( nii, "NII %s could not get initialisation info: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		return rc;
+	}
+
+	/* Determine link layer protocol */
+	switch ( db.IFtype ) {
+	case PXE_IFTYPE_ETHERNET :
+		netdev->ll_protocol = &ethernet_protocol;
+		break;
+	default:
+		DBGC ( nii, "NII %s unknown interface type %#02x\n",
+		       nii->dev.name, db.IFtype );
+		return -ENOTSUP;
+	}
+
+	/* Sanity checks */
+	assert ( db.MediaHeaderLen == netdev->ll_protocol->ll_header_len );
+	assert ( db.HWaddrLen == netdev->ll_protocol->hw_addr_len );
+	assert ( db.HWaddrLen == netdev->ll_protocol->ll_addr_len );
+
+	/* Extract parameters */
+	nii->buffer_len = db.MemoryRequired;
+	nii->mtu = ( db.FrameDataLen + db.MediaHeaderLen );
+	netdev->max_pkt_len = nii->mtu;
+
+	return 0;
+}
+
+/**
+ * Initialise UNDI
+ *
+ * @v nii		NII NIC
+ * @ret rc		Return status code
+ */
+static int nii_initialise ( struct nii_nic *nii ) {
+	PXE_CPB_INITIALIZE cpb;
+	unsigned int op;
+	int stat;
+	int rc;
+
+	/* Allocate memory buffer */
+	nii->buffer = umalloc ( nii->buffer_len );
+	if ( ! nii->buffer ) {
+		rc = -ENOMEM;
+		goto err_alloc;
+	}
+
+	/* Construct parameter block */
+	memset ( &cpb, 0, sizeof ( cpb ) );
+	cpb.MemoryAddr = ( ( intptr_t ) nii->buffer );
+	cpb.MemoryLength = nii->buffer_len;
+
+	/* Issue command */
+	op = NII_OP ( PXE_OPCODE_INITIALIZE,
+		      PXE_OPFLAGS_INITIALIZE_DO_NOT_DETECT_CABLE );
+	if ( ( stat = nii_issue_cpb ( nii, op, &cpb, sizeof ( cpb ) ) ) < 0 ) {
+		rc = -EIO_STAT ( stat );
+		DBGC ( nii, "NII %s could not initialise: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		goto err_initialize;
+	}
+
+	return 0;
+
+ err_initialize:
+	ufree ( nii->buffer );
+ err_alloc:
+	return rc;
+}
+
+/**
+ * Shut down UNDI
+ *
+ * @v nii		NII NIC
+ */
+static void nii_shutdown ( struct nii_nic *nii ) {
+	int stat;
+	int rc;
+
+	/* Issue command */
+	if ( ( stat = nii_issue ( nii, PXE_OPCODE_SHUTDOWN ) ) < 0 ) {
+		rc = -EIO_STAT ( stat );
+		DBGC ( nii, "NII %s could not shut down: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		/* Leak memory to avoid corruption */
+		return;
+	}
+
+	/* Free buffer */
+	ufree ( nii->buffer );
+}
+
+/**
+ * Get station addresses
+ *
+ * @v nii		NII NIC
+ * @v netdev		Network device to fill in
+ * @ret rc		Return status code
+ */
+static int nii_get_station_address ( struct nii_nic *nii,
+				     struct net_device *netdev ) {
+	PXE_DB_STATION_ADDRESS db;
+	int stat;
+	int rc;
+
+	/* Initialise UNDI */
+	if ( ( rc = nii_initialise ( nii ) ) != 0 )
+		goto err_initialise;
+
+	/* Issue command */
+	if ( ( stat = nii_issue_db ( nii, PXE_OPCODE_STATION_ADDRESS, &db,
+				     sizeof ( db ) ) ) < 0 ) {
+		rc = -EIO_STAT ( stat );
+		DBGC ( nii, "NII %s could not get station address: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		goto err_station_address;
+	}
+
+	/* Copy MAC addresses */
+	memcpy ( netdev->ll_addr, db.StationAddr,
+		 netdev->ll_protocol->ll_addr_len );
+	memcpy ( netdev->hw_addr, db.PermanentAddr,
+		 netdev->ll_protocol->hw_addr_len );
+	memcpy ( nii->broadcast, db.BroadcastAddr,
+		 sizeof ( nii->broadcast ) );
+
+ err_station_address:
+	nii_shutdown ( nii );
+ err_initialise:
+	return rc;
+}
+
+/**
+ * Set station address
+ *
+ * @v nii		NII NIC
+ * @v netdev		Network device
+ * @ret rc		Return status code
+ */
+static int nii_set_station_address ( struct nii_nic *nii,
+				     struct net_device *netdev ) {
+	PXE_CPB_STATION_ADDRESS cpb;
+	int stat;
+	int rc;
+
+	/* Construct parameter block */
+	memset ( &cpb, 0, sizeof ( cpb ) );
+	memcpy ( cpb.StationAddr, netdev->ll_addr,
+		 netdev->ll_protocol->ll_addr_len );
+
+	/* Issue command */
+	if ( ( stat = nii_issue_cpb ( nii, PXE_OPCODE_STATION_ADDRESS,
+				      &cpb, sizeof ( cpb ) ) ) < 0 ) {
+		rc = -EIO_STAT ( stat );
+		DBGC ( nii, "NII %s could not set station address: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * Set receive filters
+ *
+ * @v nii		NII NIC
+ * @ret rc		Return status code
+ */
+static int nii_set_rx_filters ( struct nii_nic *nii ) {
+	unsigned int op;
+	int stat;
+	int rc;
+
+	/* Issue command */
+	op = NII_OP ( PXE_OPCODE_RECEIVE_FILTERS,
+		      ( PXE_OPFLAGS_RECEIVE_FILTER_ENABLE |
+			PXE_OPFLAGS_RECEIVE_FILTER_UNICAST |
+			PXE_OPFLAGS_RECEIVE_FILTER_BROADCAST |
+			PXE_OPFLAGS_RECEIVE_FILTER_PROMISCUOUS |
+			PXE_OPFLAGS_RECEIVE_FILTER_ALL_MULTICAST ) );
+	if ( ( stat = nii_issue ( nii, op ) ) < 0 ) {
+		rc = -EIO_STAT ( stat );
+		DBGC ( nii, "NII %s could not set receive filters: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * Transmit packet
+ *
+ * @v netdev		Network device
+ * @v iobuf		I/O buffer
+ * @ret rc		Return status code
+ */
+static int nii_transmit ( struct net_device *netdev,
+			  struct io_buffer *iobuf ) {
+	struct nii_nic *nii = netdev->priv;
+	PXE_CPB_TRANSMIT cpb;
+	int stat;
+	int rc;
+
+	/* Defer the packet if there is already a transmission in progress */
+	if ( nii->txbuf ) {
+		netdev_tx_defer ( netdev, iobuf );
+		return 0;
+	}
+
+	/* Construct parameter block */
+	memset ( &cpb, 0, sizeof ( cpb ) );
+	cpb.FrameAddr = virt_to_bus ( iobuf->data );
+	cpb.DataLen = iob_len ( iobuf );
+	cpb.MediaheaderLen = netdev->ll_protocol->ll_header_len;
+
+	/* Transmit packet */
+	if ( ( stat = nii_issue_cpb ( nii, PXE_OPCODE_TRANSMIT, &cpb,
+				      sizeof ( cpb ) ) ) < 0 ) {
+		rc = -EIO_STAT ( stat );
+		DBGC ( nii, "NII %s could not transmit: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		return rc;
+	}
+	nii->txbuf = iobuf;
+
+	return 0;
+}
+
+/**
+ * Poll for completed packets
+ *
+ * @v netdev		Network device
+ * @v stat		Status flags
+ */
+static void nii_poll_tx ( struct net_device *netdev, unsigned int stat ) {
+	struct nii_nic *nii = netdev->priv;
+	struct io_buffer *iobuf;
+
+	/* Do nothing unless we have a completion */
+	if ( stat & PXE_STATFLAGS_GET_STATUS_NO_TXBUFS_WRITTEN )
+		return;
+
+	/* Sanity check */
+	if ( ! nii->txbuf ) {
+		DBGC ( nii, "NII %s reported spurious TX completion\n",
+		       nii->dev.name );
+		netdev_tx_err ( netdev, NULL, -EPIPE );
+		return;
+	}
+
+	/* Complete transmission */
+	iobuf = nii->txbuf;
+	nii->txbuf = NULL;
+	netdev_tx_complete ( netdev, iobuf );
+}
+
+/**
+ * Poll for received packets
+ *
+ * @v netdev		Network device
+ */
+static void nii_poll_rx ( struct net_device *netdev ) {
+	struct nii_nic *nii = netdev->priv;
+	PXE_CPB_RECEIVE cpb;
+	PXE_DB_RECEIVE db;
+	unsigned int quota;
+	int stat;
+	int rc;
+
+	/* Retrieve up to NII_RX_QUOTA packets */
+	for ( quota = NII_RX_QUOTA ; quota ; quota-- ) {
+
+		/* Allocate buffer, if required */
+		if ( ! nii->rxbuf ) {
+			nii->rxbuf = alloc_iob ( nii->mtu );
+			if ( ! nii->rxbuf ) {
+				/* Leave for next poll */
+				break;
+			}
+		}
+
+		/* Construct parameter block */
+		memset ( &cpb, 0, sizeof ( cpb ) );
+		cpb.BufferAddr = virt_to_bus ( nii->rxbuf->data );
+		cpb.BufferLen = iob_tailroom ( nii->rxbuf );
+
+		/* Issue command */
+		if ( ( stat = nii_issue_cpb_db ( nii, PXE_OPCODE_RECEIVE,
+						 &cpb, sizeof ( cpb ),
+						 &db, sizeof ( db ) ) ) < 0 ) {
+
+			/* PXE_STATCODE_NO_DATA is just the usual "no packet"
+			 * status indicator; ignore it.
+			 */
+			if ( stat == -PXE_STATCODE_NO_DATA )
+				break;
+
+			/* Anything else is an error */
+			rc = -EIO_STAT ( stat );
+			DBGC ( nii, "NII %s could not receive: %s\n",
+			       nii->dev.name, strerror ( rc ) );
+			netdev_rx_err ( netdev, NULL, rc );
+			break;
+		}
+
+		/* Hand off to network stack */
+		iob_put ( nii->rxbuf, db.FrameLen );
+		netdev_rx ( netdev, nii->rxbuf );
+		nii->rxbuf = NULL;
+	}
+}
+
+/**
+ * Check for link state changes
+ *
+ * @v netdev		Network device
+ * @v stat		Status flags
+ */
+static void nii_poll_link ( struct net_device *netdev, unsigned int stat ) {
+	int no_media = ( stat & PXE_STATFLAGS_GET_STATUS_NO_MEDIA );
+
+	if ( no_media && netdev_link_ok ( netdev ) ) {
+		netdev_link_down ( netdev );
+	} else if ( ( ! no_media ) && ( ! netdev_link_ok ( netdev ) ) ) {
+		netdev_link_up ( netdev );
+	}
+}
+
+/**
+ * Poll for completed packets
+ *
+ * @v netdev		Network device
+ */
+static void nii_poll ( struct net_device *netdev ) {
+	struct nii_nic *nii = netdev->priv;
+	PXE_DB_GET_STATUS db;
+	unsigned int op;
+	int stat;
+	int rc;
+
+	/* Get status */
+	op = NII_OP ( PXE_OPCODE_GET_STATUS,
+		      ( PXE_OPFLAGS_GET_INTERRUPT_STATUS |
+			PXE_OPFLAGS_GET_TRANSMITTED_BUFFERS |
+			PXE_OPFLAGS_GET_MEDIA_STATUS ) );
+	if ( ( stat = nii_issue_db ( nii, op, &db, sizeof ( db ) ) ) < 0 ) {
+		rc = -EIO_STAT ( stat );
+		DBGC ( nii, "NII %s could not get status: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		return;
+	}
+
+	/* Process any TX completions */
+	nii_poll_tx ( netdev, stat );
+
+	/* Process any RX completions */
+	nii_poll_rx ( netdev );
+
+	/* Check for link state changes */
+	nii_poll_link ( netdev, stat );
+}
+
+/**
+ * Open network device
+ *
+ * @v netdev		Network device
+ * @ret rc		Return status code
+ */
+static int nii_open ( struct net_device *netdev ) {
+	struct nii_nic *nii = netdev->priv;
+	int rc;
+
+	/* Initialise NIC */
+	if ( ( rc = nii_initialise ( nii ) ) != 0 )
+		goto err_initialise;
+
+	/* Attempt to set station address */
+	if ( ( rc = nii_set_station_address ( nii, netdev ) ) != 0 ) {
+		DBGC ( nii, "NII %s could not set station address: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		/* Treat as non-fatal */
+	}
+
+	/* Set receive filters */
+	if ( ( rc = nii_set_rx_filters ( nii ) ) != 0 )
+		goto err_set_rx_filters;
+
+	return 0;
+
+ err_set_rx_filters:
+	nii_shutdown ( nii );
+ err_initialise:
+	return rc;
+}
+
+/**
+ * Close network device
+ *
+ * @v netdev		Network device
+ */
+static void nii_close ( struct net_device *netdev ) {
+	struct nii_nic *nii = netdev->priv;
+
+	/* Shut down NIC */
+	nii_shutdown ( nii );
+
+	/* Discard transmit buffer, if applicable */
+	if ( nii->txbuf ) {
+		netdev_tx_complete_err ( netdev, nii->txbuf, -ECANCELED );
+		nii->txbuf = NULL;
+	}
+
+	/* Discard receive buffer, if applicable */
+	if ( nii->rxbuf ) {
+		free_iob ( nii->rxbuf );
+		nii->rxbuf = NULL;
+	}
+}
+
+/** NII network device operations */
+static struct net_device_operations nii_operations = {
+	.open = nii_open,
+	.close = nii_close,
+	.transmit = nii_transmit,
+	.poll = nii_poll,
+};
+
+/**
+ * Attach driver to device
+ *
+ * @v efidev		EFI device
+ * @ret rc		Return status code
+ */
+int nii_start ( struct efi_device *efidev ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	EFI_HANDLE device = efidev->device;
+	struct net_device *netdev;
+	struct nii_nic *nii;
+	void *interface;
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Allocate and initialise structure */
+	netdev = alloc_netdev ( sizeof ( *nii ) );
+	if ( ! netdev ) {
+		rc = -ENOMEM;
+		goto err_alloc;
+	}
+	netdev_init ( netdev, &nii_operations );
+	nii = netdev->priv;
+	nii->efidev = efidev;
+	netdev->ll_broadcast = nii->broadcast;
+	efidev_set_drvdata ( efidev, netdev );
+
+	/* Populate underlying device information */
+	efi_device_info ( device, "NII", &nii->dev );
+	nii->dev.driver_name = "NII";
+	nii->dev.parent = &efidev->dev;
+	list_add ( &nii->dev.siblings, &efidev->dev.children );
+	INIT_LIST_HEAD ( &nii->dev.children );
+	netdev->dev = &nii->dev;
+
+	/* Open NII protocol */
+	if ( ( efirc = bs->OpenProtocol ( device, &efi_nii31_protocol_guid,
+					  &interface, efi_image_handle, device,
+					  ( EFI_OPEN_PROTOCOL_BY_DRIVER |
+					    EFI_OPEN_PROTOCOL_EXCLUSIVE )))!=0){
+		rc = -EEFI ( efirc );
+		DBGC ( nii, "NII %s cannot open NII protocol: %s\n",
+		       nii->dev.name, strerror ( rc ) );
+		DBGC_EFI_OPENERS ( device, device, &efi_nii31_protocol_guid );
+		goto err_open_protocol;
+	}
+	nii->nii = interface;
+
+	/* Locate UNDI and entry point */
+	nii->undi = ( ( void * ) ( intptr_t ) nii->nii->Id );
+	if ( ! nii->undi ) {
+		DBGC ( nii, "NII %s has no UNDI\n", nii->dev.name );
+		rc = -ENODEV;
+		goto err_no_undi;
+	}
+	if ( nii->undi->Implementation & PXE_ROMID_IMP_HW_UNDI ) {
+		DBGC ( nii, "NII %s is a mythical hardware UNDI\n",
+		       nii->dev.name );
+		rc = -ENOTSUP;
+		goto err_hw_undi;
+	}
+	if ( nii->undi->Implementation & PXE_ROMID_IMP_SW_VIRT_ADDR ) {
+		nii->issue = ( ( void * ) ( intptr_t ) nii->undi->EntryPoint );
+	} else {
+		nii->issue = ( ( ( void * ) nii->undi ) +
+			       nii->undi->EntryPoint );
+	}
+	DBGC ( nii, "NII %s using UNDI v%x.%x at %p entry %p\n", nii->dev.name,
+	       nii->nii->MajorVer, nii->nii->MinorVer, nii->undi, nii->issue );
+
+	/* Open PCI I/O protocols and locate BARs */
+	if ( ( rc = nii_pci_open ( nii ) ) != 0 )
+		goto err_pci_open;
+
+	/* Start UNDI */
+	if ( ( rc = nii_start_undi ( nii ) ) != 0 )
+		goto err_start_undi;
+
+	/* Get initialisation information */
+	if ( ( rc = nii_get_init_info ( nii, netdev ) ) != 0 )
+		goto err_get_init_info;
+
+	/* Get MAC addresses */
+	if ( ( rc = nii_get_station_address ( nii, netdev ) ) != 0 )
+		goto err_get_station_address;
+
+	/* Register network device */
+	if ( ( rc = register_netdev ( netdev ) ) != 0 )
+		goto err_register_netdev;
+	DBGC ( nii, "NII %s registered as %s for %p %s\n", nii->dev.name,
+	       netdev->name, device, efi_handle_name ( device ) );
+
+	return 0;
+
+	unregister_netdev ( netdev );
+ err_register_netdev:
+ err_get_station_address:
+ err_get_init_info:
+	nii_stop_undi ( nii );
+ err_start_undi:
+	nii_pci_close ( nii );
+ err_pci_open:
+ err_hw_undi:
+ err_no_undi:
+	bs->CloseProtocol ( device, &efi_nii31_protocol_guid,
+			    efi_image_handle, device );
+ err_open_protocol:
+	list_del ( &nii->dev.siblings );
+	netdev_nullify ( netdev );
+	netdev_put ( netdev );
+ err_alloc:
+	return rc;
+}
+
+/**
+ * Detach driver from device
+ *
+ * @v efidev		EFI device
+ */
+void nii_stop ( struct efi_device *efidev ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	struct net_device *netdev = efidev_get_drvdata ( efidev );
+	struct nii_nic *nii = netdev->priv;
+	EFI_HANDLE device = efidev->device;
+
+	/* Unregister network device */
+	unregister_netdev ( netdev );
+
+	/* Stop UNDI */
+	nii_stop_undi ( nii );
+
+	/* Close PCI I/O protocols */
+	nii_pci_close ( nii );
+
+	/* Close NII protocol */
+	bs->CloseProtocol ( device, &efi_nii31_protocol_guid,
+			    efi_image_handle, device );
+
+	/* Free network device */
+	list_del ( &nii->dev.siblings );
+	netdev_nullify ( netdev );
+	netdev_put ( netdev );
+}
diff --git a/qemu/roms/ipxe/src/drivers/net/efi/nii.h b/qemu/roms/ipxe/src/drivers/net/efi/nii.h
new file mode 100644
index 000000000..de0ac687b
--- /dev/null
+++ b/qemu/roms/ipxe/src/drivers/net/efi/nii.h
@@ -0,0 +1,17 @@
+#ifndef _NII_H
+#define _NII_H
+
+/** @file
+ *
+ * NII driver
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+struct efi_device;
+
+extern int nii_start ( struct efi_device *efidev );
+extern void nii_stop ( struct efi_device *efidev );
+
+#endif /* _NII_H */
diff --git a/qemu/roms/ipxe/src/drivers/net/efi/snp.c b/qemu/roms/ipxe/src/drivers/net/efi/snp.c
new file mode 100644
index 000000000..2b5fc8618
--- /dev/null
+++ b/qemu/roms/ipxe/src/drivers/net/efi/snp.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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 Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <errno.h>
+#include <ipxe/efi/efi.h>
+#include <ipxe/efi/efi_driver.h>
+#include <ipxe/efi/efi_snp.h>
+#include "snpnet.h"
+#include "nii.h"
+
+/** @file
+ *
+ * SNP driver
+ *
+ */
+
+/**
+ * Check to see if driver supports a device
+ *
+ * @v device		EFI device handle
+ * @ret rc		Return status code
+ */
+static int snp_supported ( EFI_HANDLE device ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	EFI_STATUS efirc;
+
+	/* Check that this is not a device we are providing ourselves */
+	if ( find_snpdev ( device ) != NULL ) {
+		DBGCP ( device, "SNP %p %s is provided by this binary\n",
+			device, efi_handle_name ( device ) );
+		return -ENOTTY;
+	}
+
+	/* Test for presence of simple network protocol */
+	if ( ( efirc = bs->OpenProtocol ( device,
+					  &efi_simple_network_protocol_guid,
+					  NULL, efi_image_handle, device,
+					  EFI_OPEN_PROTOCOL_TEST_PROTOCOL))!=0){
+		DBGCP ( device, "SNP %p %s is not an SNP device\n",
+			device, efi_handle_name ( device ) );
+		return -EEFI ( efirc );
+	}
+	DBGC ( device, "SNP %p %s is an SNP device\n",
+	       device, efi_handle_name ( device ) );
+
+	return 0;
+}
+
+/**
+ * Check to see if driver supports a device
+ *
+ * @v device		EFI device handle
+ * @ret rc		Return status code
+ */
+static int nii_supported ( EFI_HANDLE device ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	EFI_STATUS efirc;
+
+	/* Check that this is not a device we are providing ourselves */
+	if ( find_snpdev ( device ) != NULL ) {
+		DBGCP ( device, "NII %p %s is provided by this binary\n",
+			device, efi_handle_name ( device ) );
+		return -ENOTTY;
+	}
+
+	/* Test for presence of NII protocol */
+	if ( ( efirc = bs->OpenProtocol ( device,
+					  &efi_nii31_protocol_guid,
+					  NULL, efi_image_handle, device,
+					  EFI_OPEN_PROTOCOL_TEST_PROTOCOL))!=0){
+		DBGCP ( device, "NII %p %s is not an NII device\n",
+			device, efi_handle_name ( device ) );
+		return -EEFI ( efirc );
+	}
+	DBGC ( device, "NII %p %s is an NII device\n",
+	       device, efi_handle_name ( device ) );
+
+	return 0;
+}
+
+/** EFI SNP driver */
+struct efi_driver snp_driver __efi_driver ( EFI_DRIVER_NORMAL ) = {
+	.name = "SNP",
+	.supported = snp_supported,
+	.start = snpnet_start,
+	.stop = snpnet_stop,
+};
+
+/** EFI NII driver */
+struct efi_driver nii_driver __efi_driver ( EFI_DRIVER_NORMAL ) = {
+	.name = "NII",
+	.supported = nii_supported,
+	.start = nii_start,
+	.stop = nii_stop,
+};
diff --git a/qemu/roms/ipxe/src/drivers/net/efi/snpnet.c b/qemu/roms/ipxe/src/drivers/net/efi/snpnet.c
new file mode 100644
index 000000000..96642c4ca
--- /dev/null
+++ b/qemu/roms/ipxe/src/drivers/net/efi/snpnet.c
@@ -0,0 +1,563 @@
+/*
+ * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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 Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <ipxe/iobuf.h>
+#include <ipxe/netdevice.h>
+#include <ipxe/ethernet.h>
+#include <ipxe/vsprintf.h>
+#include <ipxe/efi/efi.h>
+#include <ipxe/efi/Protocol/SimpleNetwork.h>
+#include <ipxe/efi/efi_driver.h>
+#include <ipxe/efi/efi_utils.h>
+#include "snpnet.h"
+
+/** @file
+ *
+ * SNP NIC driver
+ *
+ */
+
+/** An SNP NIC */
+struct snp_nic {
+	/** EFI device */
+	struct efi_device *efidev;
+	/** Simple network protocol */
+	EFI_SIMPLE_NETWORK_PROTOCOL *snp;
+	/** Generic device */
+	struct device dev;
+
+	/** Maximum packet size
+	 *
+	 * This is calculated as the sum of MediaHeaderSize and
+	 * MaxPacketSize, and may therefore be an overestimate.
+	 */
+	size_t mtu;
+
+	/** Current transmit buffer */
+	struct io_buffer *txbuf;
+	/** Current receive buffer */
+	struct io_buffer *rxbuf;
+};
+
+/** Maximum number of received packets per poll */
+#define SNP_RX_QUOTA 4
+
+/**
+ * Format SNP MAC address (for debugging)
+ *
+ * @v mac		MAC address
+ * @v len		Length of MAC address
+ * @ret text		MAC address as text
+ */
+static const char * snpnet_mac_text ( EFI_MAC_ADDRESS *mac, size_t len ) {
+	static char buf[ sizeof ( *mac ) * 3 /* "xx:" or "xx\0" */ ];
+	size_t used = 0;
+	unsigned int i;
+
+	for ( i = 0 ; i < len ; i++ ) {
+		used += ssnprintf ( &buf[used], ( sizeof ( buf ) - used ),
+				    "%s%02x", ( used ? ":" : "" ),
+				    mac->Addr[i] );
+	}
+	return buf;
+}
+
+/**
+ * Dump SNP mode information (for debugging)
+ *
+ * @v netdev		Network device
+ */
+static void snpnet_dump_mode ( struct net_device *netdev ) {
+	struct snp_nic *snp = netdev_priv ( netdev );
+	EFI_SIMPLE_NETWORK_MODE *mode = snp->snp->Mode;
+	size_t mac_len = mode->HwAddressSize;
+	unsigned int i;
+
+	/* Do nothing unless debugging is enabled */
+	if ( ! DBG_EXTRA )
+		return;
+
+	DBGC2 ( snp, "SNP %s st %d type %d hdr %d pkt %d rxflt %#x/%#x%s "
+		"nvram %d acc %d mcast %d/%d\n", netdev->name, mode->State,
+		mode->IfType, mode->MediaHeaderSize, mode->MaxPacketSize,
+		mode->ReceiveFilterSetting, mode->ReceiveFilterMask,
+		( mode->MultipleTxSupported ? " multitx" : "" ),
+		mode->NvRamSize, mode->NvRamAccessSize,
+		mode->MCastFilterCount, mode->MaxMCastFilterCount );
+	DBGC2 ( snp, "SNP %s hw %s", netdev->name,
+		snpnet_mac_text ( &mode->PermanentAddress, mac_len ) );
+	DBGC2 ( snp, " addr %s%s",
+		snpnet_mac_text ( &mode->CurrentAddress, mac_len ),
+		( mode->MacAddressChangeable ? "" : "(f)" ) );
+	DBGC2 ( snp, " bcast %s\n",
+		snpnet_mac_text ( &mode->BroadcastAddress, mac_len ) );
+	for ( i = 0 ; i < mode->MCastFilterCount ; i++ ) {
+		DBGC2 ( snp, "SNP %s mcast %s\n", netdev->name,
+			snpnet_mac_text ( &mode->MCastFilter[i], mac_len ) );
+	}
+	DBGC2 ( snp, "SNP %s media %s\n", netdev->name,
+		( mode->MediaPresentSupported ?
+		  ( mode->MediaPresent ? "present" : "not present" ) :
+		  "presence not supported" ) );
+}
+
+/**
+ * Check link state
+ *
+ * @v netdev		Network device
+ */
+static void snpnet_check_link ( struct net_device *netdev ) {
+	struct snp_nic *snp = netdev_priv ( netdev );
+	EFI_SIMPLE_NETWORK_MODE *mode = snp->snp->Mode;
+
+	/* Do nothing unless media presence detection is supported */
+	if ( ! mode->MediaPresentSupported )
+		return;
+
+	/* Report any link status change */
+	if ( mode->MediaPresent && ( ! netdev_link_ok ( netdev ) ) ) {
+		netdev_link_up ( netdev );
+	} else if ( ( ! mode->MediaPresent ) && netdev_link_ok ( netdev ) ) {
+		netdev_link_down ( netdev );
+	}
+}
+
+/**
+ * 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 snp_nic *snp = netdev_priv ( netdev );
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Defer the packet if there is already a transmission in progress */
+	if ( snp->txbuf ) {
+		netdev_tx_defer ( netdev, iobuf );
+		return 0;
+	}
+
+	/* Transmit packet */
+	if ( ( efirc = snp->snp->Transmit ( snp->snp, 0, iob_len ( iobuf ),
+					    iobuf->data, NULL, NULL,
+					    NULL ) ) != 0 ) {
+		rc = -EEFI ( efirc );
+		DBGC ( snp, "SNP %s could not transmit: %s\n",
+		       netdev->name, strerror ( rc ) );
+		return rc;
+	}
+	snp->txbuf = iobuf;
+
+	return 0;
+}
+
+/**
+ * Poll for completed packets
+ *
+ * @v netdev		Network device
+ */
+static void snpnet_poll_tx ( struct net_device *netdev ) {
+	struct snp_nic *snp = netdev->priv;
+	struct io_buffer *iobuf;
+	UINT32 irq;
+	VOID *txbuf;
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Get status */
+	if ( ( efirc = snp->snp->GetStatus ( snp->snp, &irq, &txbuf ) ) != 0 ) {
+		rc = -EEFI ( efirc );
+		DBGC ( snp, "SNP %s could not get status: %s\n",
+		       netdev->name, strerror ( rc ) );
+		netdev_rx_err ( netdev, NULL, rc );
+		return;
+	}
+
+	/* Do nothing unless we have a completion */
+	if ( ! txbuf )
+		return;
+
+	/* Sanity check */
+	if ( ! snp->txbuf ) {
+		DBGC ( snp, "SNP %s reported spurious TX completion\n",
+		       netdev->name );
+		netdev_tx_err ( netdev, NULL, -EPIPE );
+		return;
+	}
+
+	/* Complete transmission */
+	iobuf = snp->txbuf;
+	snp->txbuf = NULL;
+	netdev_tx_complete ( netdev, iobuf );
+}
+
+/**
+ * Poll for received packets
+ *
+ * @v netdev		Network device
+ */
+static void snpnet_poll_rx ( struct net_device *netdev ) {
+	struct snp_nic *snp = netdev->priv;
+	UINTN len;
+	unsigned int quota;
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Retrieve up to SNP_RX_QUOTA packets */
+	for ( quota = SNP_RX_QUOTA ; quota ; quota-- ) {
+
+		/* Allocate buffer, if required */
+		if ( ! snp->rxbuf ) {
+			snp->rxbuf = alloc_iob ( snp->mtu );
+			if ( ! snp->rxbuf ) {
+				/* Leave for next poll */
+				break;
+			}
+		}
+
+		/* Receive packet */
+		len = iob_tailroom ( snp->rxbuf );
+		if ( ( efirc = snp->snp->Receive ( snp->snp, NULL, &len,
+						   snp->rxbuf->data, NULL,
+						   NULL, NULL ) ) != 0 ) {
+
+			/* EFI_NOT_READY is just the usual "no packet"
+			 * status indication; ignore it.
+			 */
+			if ( efirc == EFI_NOT_READY )
+				break;
+
+			/* Anything else is an error */
+			rc = -EEFI ( efirc );
+			DBGC ( snp, "SNP %s could not receive: %s\n",
+			       netdev->name, strerror ( rc ) );
+			netdev_rx_err ( netdev, NULL, rc );
+			break;
+		}
+
+		/* Hand off to network stack */
+		iob_put ( snp->rxbuf, len );
+		netdev_rx ( netdev, snp->rxbuf );
+		snp->rxbuf = NULL;
+	}
+}
+
+/**
+ * Poll for completed packets
+ *
+ * @v netdev		Network device
+ */
+static void snpnet_poll ( struct net_device *netdev ) {
+
+	/* Process any TX completions */
+	snpnet_poll_tx ( netdev );
+
+	/* Process any RX completions */
+	snpnet_poll_rx ( netdev );
+
+	/* Check for link state changes */
+	snpnet_check_link ( netdev );
+}
+
+/**
+ * Set receive filters
+ *
+ * @v netdev		Network device
+ * @ret rc		Return status code
+ */
+static int snpnet_rx_filters ( struct net_device *netdev ) {
+	struct snp_nic *snp = netdev->priv;
+	UINT32 filters[] = {
+		snp->snp->Mode->ReceiveFilterMask,
+		( EFI_SIMPLE_NETWORK_RECEIVE_UNICAST |
+		  EFI_SIMPLE_NETWORK_RECEIVE_MULTICAST |
+		  EFI_SIMPLE_NETWORK_RECEIVE_BROADCAST ),
+		( EFI_SIMPLE_NETWORK_RECEIVE_UNICAST |
+		  EFI_SIMPLE_NETWORK_RECEIVE_BROADCAST ),
+		( EFI_SIMPLE_NETWORK_RECEIVE_UNICAST ),
+	};
+	unsigned int i;
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Try possible receive filters in turn */
+	for ( i = 0; i < ( sizeof ( filters ) / sizeof ( filters[0] ) ); i++ ) {
+		efirc = snp->snp->ReceiveFilters ( snp->snp, filters[i],
+						   0, TRUE, 0, NULL );
+		if ( efirc == 0 )
+			return 0;
+		rc = -EEFI ( efirc );
+		DBGC ( snp, "SNP %s could not set receive filters %#02x (have "
+		       "%#02x): %s\n", netdev->name, filters[i],
+		       snp->snp->Mode->ReceiveFilterSetting, strerror ( rc ) );
+	}
+
+	return rc;
+}
+
+/**
+ * Open network device
+ *
+ * @v netdev		Network device
+ * @ret rc		Return status code
+ */
+static int snpnet_open ( struct net_device *netdev ) {
+	struct snp_nic *snp = netdev->priv;
+	EFI_MAC_ADDRESS *mac = ( ( void * ) netdev->ll_addr );
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Try setting MAC address (before initialising) */
+	if ( ( efirc = snp->snp->StationAddress ( snp->snp, FALSE, mac ) ) !=0){
+		rc = -EEFI ( efirc );
+		DBGC ( snp, "SNP %s could not set station address before "
+		       "initialising: %s\n", netdev->name, strerror ( rc ) );
+		/* Ignore error */
+	}
+
+	/* Initialise NIC */
+	if ( ( efirc = snp->snp->Initialize ( snp->snp, 0, 0 ) ) != 0 ) {
+		rc = -EEFI ( efirc );
+		snpnet_dump_mode ( netdev );
+		DBGC ( snp, "SNP %s could not initialise: %s\n",
+		       netdev->name, strerror ( rc ) );
+		return rc;
+	}
+
+	/* Try setting MAC address (after initialising) */
+	if ( ( efirc = snp->snp->StationAddress ( snp->snp, FALSE, mac ) ) !=0){
+		rc = -EEFI ( efirc );
+		DBGC ( snp, "SNP %s could not set station address after "
+		       "initialising: %s\n", netdev->name, strerror ( rc ) );
+		/* Ignore error */
+	}
+
+	/* Set receive filters */
+	if ( ( rc = snpnet_rx_filters ( netdev ) ) != 0 ) {
+		/* Ignore error */
+	}
+
+	/* Dump mode information (for debugging) */
+	snpnet_dump_mode ( netdev );
+
+	return 0;
+}
+
+/**
+ * Close network device
+ *
+ * @v netdev		Network device
+ */
+static void snpnet_close ( struct net_device *netdev ) {
+	struct snp_nic *snp = netdev->priv;
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Shut down NIC */
+	if ( ( efirc = snp->snp->Shutdown ( snp->snp ) ) != 0 ) {
+		rc = -EEFI ( efirc );
+		DBGC ( snp, "SNP %s could not shut down: %s\n",
+		       netdev->name, strerror ( rc ) );
+		/* Nothing we can do about this */
+	}
+
+	/* Discard transmit buffer, if applicable */
+	if ( snp->txbuf ) {
+		netdev_tx_complete_err ( netdev, snp->txbuf, -ECANCELED );
+		snp->txbuf = NULL;
+	}
+
+	/* Discard receive buffer, if applicable */
+	if ( snp->rxbuf ) {
+		free_iob ( snp->rxbuf );
+		snp->rxbuf = NULL;
+	}
+}
+
+/** SNP network device operations */
+static struct net_device_operations snpnet_operations = {
+	.open = snpnet_open,
+	.close = snpnet_close,
+	.transmit = snpnet_transmit,
+	.poll = snpnet_poll,
+};
+
+/**
+ * Attach driver to device
+ *
+ * @v efidev		EFI device
+ * @ret rc		Return status code
+ */
+int snpnet_start ( struct efi_device *efidev ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	EFI_HANDLE device = efidev->device;
+	EFI_SIMPLE_NETWORK_MODE *mode;
+	struct net_device *netdev;
+	struct snp_nic *snp;
+	void *interface;
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Open SNP protocol */
+	if ( ( efirc = bs->OpenProtocol ( device,
+					  &efi_simple_network_protocol_guid,
+					  &interface, efi_image_handle, device,
+					  ( EFI_OPEN_PROTOCOL_BY_DRIVER |
+					    EFI_OPEN_PROTOCOL_EXCLUSIVE )))!=0){
+		rc = -EEFI ( efirc );
+		DBGC ( device, "SNP %p %s cannot open SNP protocol: %s\n",
+		       device, efi_handle_name ( device ), strerror ( rc ) );
+		DBGC_EFI_OPENERS ( device, device,
+				   &efi_simple_network_protocol_guid );
+		goto err_open_protocol;
+	}
+
+	/* Allocate and initialise structure */
+	netdev = alloc_etherdev ( sizeof ( *snp ) );
+	if ( ! netdev ) {
+		rc = -ENOMEM;
+		goto err_alloc;
+	}
+	netdev_init ( netdev, &snpnet_operations );
+	snp = netdev->priv;
+	snp->efidev = efidev;
+	snp->snp = interface;
+	mode = snp->snp->Mode;
+	efidev_set_drvdata ( efidev, netdev );
+
+	/* Populate underlying device information */
+	efi_device_info ( device, "SNP", &snp->dev );
+	snp->dev.driver_name = "SNP";
+	snp->dev.parent = &efidev->dev;
+	list_add ( &snp->dev.siblings, &efidev->dev.children );
+	INIT_LIST_HEAD ( &snp->dev.children );
+	netdev->dev = &snp->dev;
+
+	/* Bring to the Started state */
+	if ( ( mode->State == EfiSimpleNetworkStopped ) &&
+	     ( ( efirc = snp->snp->Start ( snp->snp ) ) != 0 ) ) {
+		rc = -EEFI ( efirc );
+		DBGC ( device, "SNP %p %s could not start: %s\n", device,
+		       efi_handle_name ( device ), strerror ( rc ) );
+		goto err_start;
+	}
+	if ( ( mode->State == EfiSimpleNetworkInitialized ) &&
+	     ( ( efirc = snp->snp->Shutdown ( snp->snp ) ) != 0 ) ) {
+		rc = -EEFI ( efirc );
+		DBGC ( device, "SNP %p %s could not shut down: %s\n", device,
+		       efi_handle_name ( device ), strerror ( rc ) );
+		goto err_shutdown;
+	}
+
+	/* Populate network device parameters */
+	if ( mode->HwAddressSize != netdev->ll_protocol->hw_addr_len ) {
+		DBGC ( device, "SNP %p %s has invalid hardware address "
+		       "length %d\n", device, efi_handle_name ( device ),
+		       mode->HwAddressSize );
+		rc = -ENOTSUP;
+		goto err_hw_addr_len;
+	}
+	memcpy ( netdev->hw_addr, &mode->PermanentAddress,
+		 netdev->ll_protocol->hw_addr_len );
+	if ( mode->HwAddressSize != netdev->ll_protocol->ll_addr_len ) {
+		DBGC ( device, "SNP %p %s has invalid link-layer address "
+		       "length %d\n", device, efi_handle_name ( device ),
+		       mode->HwAddressSize );
+		rc = -ENOTSUP;
+		goto err_ll_addr_len;
+	}
+	memcpy ( netdev->ll_addr, &mode->CurrentAddress,
+		 netdev->ll_protocol->ll_addr_len );
+	snp->mtu = ( snp->snp->Mode->MaxPacketSize +
+		     snp->snp->Mode->MediaHeaderSize );
+
+	/* Register network device */
+	if ( ( rc = register_netdev ( netdev ) ) != 0 )
+		goto err_register_netdev;
+	DBGC ( device, "SNP %p %s registered as %s\n",
+	       device, efi_handle_name ( device ), netdev->name );
+
+	/* Set initial link state */
+	if ( snp->snp->Mode->MediaPresentSupported ) {
+		snpnet_check_link ( netdev );
+	} else {
+		netdev_link_up ( netdev );
+	}
+
+	return 0;
+
+	unregister_netdev ( netdev );
+ err_register_netdev:
+ err_ll_addr_len:
+ err_hw_addr_len:
+ err_shutdown:
+ err_start:
+	list_del ( &snp->dev.siblings );
+	netdev_nullify ( netdev );
+	netdev_put ( netdev );
+ err_alloc:
+	bs->CloseProtocol ( device, &efi_simple_network_protocol_guid,
+			    efi_image_handle, device );
+ err_open_protocol:
+	return rc;
+}
+
+/**
+ * Detach driver from device
+ *
+ * @v efidev		EFI device
+  */
+void snpnet_stop ( struct efi_device *efidev ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	struct net_device *netdev = efidev_get_drvdata ( efidev );
+	struct snp_nic *snp = netdev->priv;
+	EFI_HANDLE device = efidev->device;
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Unregister network device */
+	unregister_netdev ( netdev );
+
+	/* Stop SNP protocol */
+	if ( ( efirc = snp->snp->Stop ( snp->snp ) ) != 0 ) {
+		rc = -EEFI ( efirc );
+		DBGC ( device, "SNP %p %s could not stop: %s\n", device,
+		       efi_handle_name ( device ), strerror ( rc ) );
+		/* Nothing we can do about this */
+	}
+
+	/* Free network device */
+	list_del ( &snp->dev.siblings );
+	netdev_nullify ( netdev );
+	netdev_put ( netdev );
+
+	/* Close SNP protocol */
+	bs->CloseProtocol ( device, &efi_simple_network_protocol_guid,
+			    efi_image_handle, device );
+}
diff --git a/qemu/roms/ipxe/src/drivers/net/efi/snpnet.h b/qemu/roms/ipxe/src/drivers/net/efi/snpnet.h
new file mode 100644
index 000000000..e6d31d5e4
--- /dev/null
+++ b/qemu/roms/ipxe/src/drivers/net/efi/snpnet.h
@@ -0,0 +1,17 @@
+#ifndef _SNPNET_H
+#define _SNPNET_H
+
+/** @file
+ *
+ * SNP NIC driver
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+struct efi_device;
+
+extern int snpnet_start ( struct efi_device *efidev );
+extern void snpnet_stop ( struct efi_device *efidev );
+
+#endif /* _SNPNET_H */
diff --git a/qemu/roms/ipxe/src/drivers/net/efi/snponly.c b/qemu/roms/ipxe/src/drivers/net/efi/snponly.c
new file mode 100644
index 000000000..99f264bca
--- /dev/null
+++ b/qemu/roms/ipxe/src/drivers/net/efi/snponly.c
@@ -0,0 +1,208 @@
+/*
+ * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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 Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <string.h>
+#include <errno.h>
+#include <ipxe/init.h>
+#include <ipxe/efi/efi.h>
+#include <ipxe/efi/efi_driver.h>
+#include <ipxe/efi/efi_utils.h>
+#include <ipxe/efi/Protocol/SimpleNetwork.h>
+#include <ipxe/efi/Protocol/NetworkInterfaceIdentifier.h>
+#include "snpnet.h"
+#include "nii.h"
+
+/** @file
+ *
+ * EFI chainloaded-device-only driver
+ *
+ */
+
+/** A chainloaded protocol */
+struct chained_protocol {
+	/** Protocol GUID */
+	EFI_GUID *protocol;
+	/**
+	 * Protocol instance installed on the loaded image's device handle
+	 *
+	 * We match against the protocol instance (rather than simply
+	 * matching against the device handle itself) because some
+	 * systems load us via a child of the underlying device, with
+	 * a duplicate protocol installed on the child handle.
+	 */
+	void *interface;
+};
+
+/** Chainloaded SNP protocol */
+static struct chained_protocol chained_snp = {
+	.protocol = &efi_simple_network_protocol_guid,
+};
+
+/** Chainloaded NII protocol */
+static struct chained_protocol chained_nii = {
+	.protocol = &efi_nii31_protocol_guid,
+};
+
+/**
+ * Locate chainloaded protocol instance
+ *
+ * @v chained		Chainloaded protocol
+ * @ret rc		Return status code
+ */
+static int chained_locate ( struct chained_protocol *chained ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	EFI_HANDLE device = efi_loaded_image->DeviceHandle;
+	EFI_HANDLE parent;
+	EFI_STATUS efirc;
+	int rc;
+
+	/* Locate handle supporting this protocol */
+	if ( ( rc = efi_locate_device ( device, chained->protocol,
+					&parent ) ) != 0 ) {
+		DBGC ( device, "CHAINED %p %s does not support %s: %s\n",
+		       device, efi_handle_name ( device ),
+		       efi_guid_ntoa ( chained->protocol ), strerror ( rc ) );
+		goto err_locate_device;
+	}
+	DBGC ( device, "CHAINED %p %s found %s on ", device,
+	       efi_handle_name ( device ), efi_guid_ntoa ( chained->protocol ));
+	DBGC ( device, "%p %s\n", parent, efi_handle_name ( parent ) );
+
+	/* Get protocol instance */
+	if ( ( efirc = bs->OpenProtocol ( parent, chained->protocol,
+					  &chained->interface, efi_image_handle,
+					  device,
+					  EFI_OPEN_PROTOCOL_GET_PROTOCOL ))!=0){
+		rc = -EEFI ( efirc );
+		DBGC ( device, "CHAINED %p %s could not open %s on ",
+		       device, efi_handle_name ( device ),
+		       efi_guid_ntoa ( chained->protocol ) );
+		DBGC ( device, "%p %s: %s\n",
+		       parent, efi_handle_name ( parent ), strerror ( rc ) );
+		goto err_open_protocol;
+	}
+
+ err_locate_device:
+	bs->CloseProtocol ( parent, chained->protocol, efi_image_handle,
+			    device );
+ err_open_protocol:
+	return rc;
+}
+
+/**
+ * Check to see if driver supports a device
+ *
+ * @v device		EFI device handle
+ * @v chained		Chainloaded protocol
+ * @ret rc		Return status code
+ */
+static int chained_supported ( EFI_HANDLE device,
+			       struct chained_protocol *chained ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	EFI_STATUS efirc;
+	void *interface;
+	int rc;
+
+	/* Get protocol */
+	if ( ( efirc = bs->OpenProtocol ( device, chained->protocol, &interface,
+					  efi_image_handle, device,
+					  EFI_OPEN_PROTOCOL_GET_PROTOCOL ))!=0){
+		rc = -EEFI ( efirc );
+		DBGCP ( device, "CHAINED %p %s is not a %s device\n",
+			device, efi_handle_name ( device ),
+			efi_guid_ntoa ( chained->protocol ) );
+		goto err_open_protocol;
+	}
+
+	/* Test for a match against the chainloading device */
+	if ( interface != chained->interface ) {
+		DBGC ( device, "CHAINED %p %s %p is not the chainloaded "
+		       "%s\n", device, efi_handle_name ( device ),
+		       interface, efi_guid_ntoa ( chained->protocol ) );
+		rc = -ENOTTY;
+		goto err_no_match;
+	}
+
+	/* Success */
+	rc = 0;
+	DBGC ( device, "CHAINED %p %s %p is the chainloaded %s\n",
+	       device, efi_handle_name ( device ), interface,
+	       efi_guid_ntoa ( chained->protocol ) );
+
+ err_no_match:
+	bs->CloseProtocol ( device, chained->protocol, efi_image_handle,
+			    device );
+ err_open_protocol:
+	return rc;
+}
+
+/**
+ * Check to see if driver supports a device
+ *
+ * @v device		EFI device handle
+ * @ret rc		Return status code
+ */
+static int snponly_supported ( EFI_HANDLE device ) {
+
+	return chained_supported ( device, &chained_snp );
+}
+
+/**
+ * Check to see if driver supports a device
+ *
+ * @v device		EFI device handle
+ * @ret rc		Return status code
+ */
+static int niionly_supported ( EFI_HANDLE device ) {
+
+	return chained_supported ( device, &chained_nii );
+}
+
+/** EFI SNP chainloading-device-only driver */
+struct efi_driver snponly_driver __efi_driver ( EFI_DRIVER_NORMAL ) = {
+	.name = "SNPONLY",
+	.supported = snponly_supported,
+	.start = snpnet_start,
+	.stop = snpnet_stop,
+};
+
+/** EFI NII chainloading-device-only driver */
+struct efi_driver niionly_driver __efi_driver ( EFI_DRIVER_NORMAL ) = {
+	.name = "NIIONLY",
+	.supported = niionly_supported,
+	.start = nii_start,
+	.stop = nii_stop,
+};
+
+/**
+ * Initialise EFI chainloaded-device-only driver
+ *
+ */
+static void chained_init ( void ) {
+
+	chained_locate ( &chained_snp );
+	chained_locate ( &chained_nii );
+}
+
+/** EFI chainloaded-device-only initialisation function */
+struct init_fn chained_init_fn __init_fn ( INIT_LATE ) = {
+	.initialise = chained_init,
+};