Initial import of qemu-2.4.1HEADmaster

7 files changed, 1649 insertions, 0 deletions

diff --git a/roms/ipxe/src/arch/i386/drivers/net/undi.c b/roms/ipxe/src/arch/i386/drivers/net/undi.c
new file mode 100644
index 00000000..2bc54824
--- /dev/null
+++ b/roms/ipxe/src/arch/i386/drivers/net/undi.c
@@ -0,0 +1,149 @@
+/*
+ * Copyright (C) 2007 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 <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <ipxe/pci.h>
+#include <undi.h>
+#include <undirom.h>
+#include <undiload.h>
+#include <undinet.h>
+#include <undipreload.h>
+
+/** @file
+ *
+ * UNDI PCI driver
+ *
+ */
+
+/**
+ * Find UNDI ROM for PCI device
+ *
+ * @v pci		PCI device
+ * @ret undirom		UNDI ROM, or NULL
+ *
+ * Try to find a driver for this device.  Try an exact match on the
+ * ROM address first, then fall back to a vendor/device ID match only
+ */
+static struct undi_rom * undipci_find_rom ( struct pci_device *pci ) {
+	struct undi_rom *undirom;
+	unsigned long rombase;
+	
+	rombase = pci_bar_start ( pci, PCI_ROM_ADDRESS );
+	undirom = undirom_find_pci ( pci->vendor, pci->device, rombase );
+	if ( ! undirom )
+		undirom = undirom_find_pci ( pci->vendor, pci->device, 0 );
+	return undirom;
+}
+
+/**
+ * Probe PCI device
+ *
+ * @v pci		PCI device
+ * @v id		PCI ID
+ * @ret rc		Return status code
+ */
+static int undipci_probe ( struct pci_device *pci ) {
+	struct undi_device *undi;
+	struct undi_rom *undirom;
+	int rc;
+
+	/* Ignore non-network devices */
+	if ( PCI_BASE_CLASS ( pci->class ) != PCI_BASE_CLASS_NETWORK )
+		return -ENOTTY;
+
+	/* Allocate UNDI device structure */
+	undi = zalloc ( sizeof ( *undi ) );
+	if ( ! undi )
+		return -ENOMEM;
+	pci_set_drvdata ( pci, undi );
+
+	/* Find/create our pixie */
+	if ( preloaded_undi.pci_busdevfn == pci->busdevfn ) {
+		/* Claim preloaded UNDI device */
+		DBGC ( undi, "UNDI %p using preloaded UNDI device\n", undi );
+		memcpy ( undi, &preloaded_undi, sizeof ( *undi ) );
+		memset ( &preloaded_undi, 0, sizeof ( preloaded_undi ) );
+	} else {
+		/* Find UNDI ROM for PCI device */
+		if ( ! ( undirom = undipci_find_rom ( pci ) ) ) {
+			rc = -ENODEV;
+			goto err_find_rom;
+		}
+
+		/* Call UNDI ROM loader to create pixie */
+		if ( ( rc = undi_load_pci ( undi, undirom,
+					    pci->busdevfn ) ) != 0 ) {
+			goto err_load_pci;
+		}
+	}
+
+	/* Add to device hierarchy */
+	snprintf ( undi->dev.name, sizeof ( undi->dev.name ),
+		   "UNDI-%s", pci->dev.name );
+	memcpy ( &undi->dev.desc, &pci->dev.desc, sizeof ( undi->dev.desc ) );
+	undi->dev.parent = &pci->dev;
+	INIT_LIST_HEAD ( &undi->dev.children );
+	list_add ( &undi->dev.siblings, &pci->dev.children );
+
+	/* Create network device */
+	if ( ( rc = undinet_probe ( undi ) ) != 0 )
+		goto err_undinet_probe;
+	
+	return 0;
+
+ err_undinet_probe:
+	undi_unload ( undi );
+	list_del ( &undi->dev.siblings );
+ err_find_rom:
+ err_load_pci:
+	free ( undi );
+	pci_set_drvdata ( pci, NULL );
+	return rc;
+}
+
+/**
+ * Remove PCI device
+ *
+ * @v pci	PCI device
+ */
+static void undipci_remove ( struct pci_device *pci ) {
+	struct undi_device *undi = pci_get_drvdata ( pci );
+
+	undinet_remove ( undi );
+	undi_unload ( undi );
+	list_del ( &undi->dev.siblings );
+	free ( undi );
+	pci_set_drvdata ( pci, NULL );
+}
+
+static struct pci_device_id undipci_nics[] = {
+PCI_ROM ( 0xffff, 0xffff, "undipci", "UNDI (PCI)", 0 ),
+};
+
+struct pci_driver undipci_driver __pci_driver_fallback = {
+	.ids = undipci_nics,
+	.id_count = ( sizeof ( undipci_nics ) / sizeof ( undipci_nics[0] ) ),
+	.probe = undipci_probe,
+	.remove = undipci_remove,
+};
diff --git a/roms/ipxe/src/arch/i386/drivers/net/undiisr.S b/roms/ipxe/src/arch/i386/drivers/net/undiisr.S
new file mode 100644
index 00000000..b27effe1
--- /dev/null
+++ b/roms/ipxe/src/arch/i386/drivers/net/undiisr.S
@@ -0,0 +1,87 @@
+FILE_LICENCE ( GPL2_OR_LATER )
+
+#define PXENV_UNDI_ISR 0x0014
+#define PXENV_UNDI_ISR_IN_START 1
+#define PXENV_UNDI_ISR_OUT_OURS 0
+#define PXENV_UNDI_ISR_OUT_NOT_OURS 1
+
+#define IRQ_PIC_CUTOFF 8
+#define ICR_EOI_NON_SPECIFIC 0x20
+#define PIC1_ICR 0x20
+#define PIC2_ICR 0xa0
+	
+	.text
+	.arch i386
+	.code16
+
+	.section ".text16", "ax", @progbits
+	.globl undiisr
+undiisr:
+	
+	/* Preserve registers */
+	pushw	%ds
+	pushw	%es
+	pushw	%fs
+	pushw	%gs
+	pushfl
+	pushal
+
+	/* Set up our segment registers */
+	movw	%cs:rm_ds, %ax
+	movw	%ax, %ds
+
+	/* Check that we have an UNDI entry point */
+	cmpw	$0, pxeparent_entry_point
+	je	chain
+	
+	/* Issue UNDI API call */
+	movw	%ax, %es
+	movw	$undinet_params, %di
+	movw	$PXENV_UNDI_ISR, %bx
+	movw	$PXENV_UNDI_ISR_IN_START, funcflag
+	pushw	%es
+	pushw	%di
+	pushw	%bx
+	lcall	*pxeparent_entry_point
+	cli	/* Just in case */
+	addw	$6, %sp
+	cmpw	$PXENV_UNDI_ISR_OUT_OURS, funcflag
+	jne	eoi
+	
+trig:	/* Record interrupt occurence */
+	incb	undiisr_trigger_count
+
+eoi:	/* Send EOI */
+	movb	$ICR_EOI_NON_SPECIFIC, %al
+	cmpb	$IRQ_PIC_CUTOFF, undiisr_irq
+	jb	1f
+	outb	%al, $PIC2_ICR
+1:	outb	%al, $PIC1_ICR
+	jmp	exit
+	
+chain:	/* Chain to next handler */
+	pushfw
+	lcall	*undiisr_next_handler
+	
+exit:	/* Restore registers and return */
+	cli
+	popal
+	movzwl	%sp, %esp
+	addr32	movl -20(%esp), %esp	/* %esp isn't restored by popal */
+	popfl
+	popw	%gs
+	popw	%fs
+	popw	%es
+	popw	%ds
+	iret
+
+	.section ".data16", "aw", @progbits
+undinet_params:
+status:			.word	0
+funcflag:		.word	0
+bufferlength:		.word	0
+framelength:		.word	0
+frameheaderlength:	.word	0
+frame:			.word	0, 0
+prottype:		.byte	0
+pkttype:		.byte	0
diff --git a/roms/ipxe/src/arch/i386/drivers/net/undiload.c b/roms/ipxe/src/arch/i386/drivers/net/undiload.c
new file mode 100644
index 00000000..77134dcb
--- /dev/null
+++ b/roms/ipxe/src/arch/i386/drivers/net/undiload.c
@@ -0,0 +1,180 @@
+/*
+ * Copyright (C) 2007 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 <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <pxe.h>
+#include <realmode.h>
+#include <bios.h>
+#include <pnpbios.h>
+#include <basemem.h>
+#include <ipxe/pci.h>
+#include <undi.h>
+#include <undirom.h>
+#include <undiload.h>
+
+/** @file
+ *
+ * UNDI load/unload
+ *
+ */
+
+/* Disambiguate the various error causes */
+#define EINFO_EUNDILOAD							\
+	__einfo_uniqify ( EINFO_EPLATFORM, 0x01,			\
+			  "UNDI loader error" )
+#define EUNDILOAD( status ) EPLATFORM ( EINFO_EUNDILOAD, status )
+
+/** Parameter block for calling UNDI loader */
+static struct s_UNDI_LOADER __bss16 ( undi_loader );
+#define undi_loader __use_data16 ( undi_loader )
+
+/** UNDI loader entry point */
+static SEGOFF16_t __bss16 ( undi_loader_entry );
+#define undi_loader_entry __use_data16 ( undi_loader_entry )
+
+/**
+ * Call UNDI loader to create a pixie
+ *
+ * @v undi		UNDI device
+ * @v undirom		UNDI ROM
+ * @ret rc		Return status code
+ */
+int undi_load ( struct undi_device *undi, struct undi_rom *undirom ) {
+	struct s_PXE ppxe;
+	unsigned int fbms_seg;
+	uint16_t exit;
+	int rc;
+
+	/* Only one UNDI instance may be loaded at any given time */
+	if ( undi_loader_entry.segment ) {
+		DBG ( "UNDI %p cannot load multiple instances\n", undi );
+		return -EBUSY;
+	}
+
+	/* Set up START_UNDI parameters */
+	memset ( &undi_loader, 0, sizeof ( undi_loader ) );
+	undi_loader.AX = undi->pci_busdevfn;
+	undi_loader.BX = undi->isapnp_csn;
+	undi_loader.DX = undi->isapnp_read_port;
+	undi_loader.ES = BIOS_SEG;
+	undi_loader.DI = find_pnp_bios();
+
+	/* Allocate base memory for PXE stack */
+	undi->restore_fbms = get_fbms();
+	fbms_seg = ( undi->restore_fbms << 6 );
+	fbms_seg -= ( ( undirom->code_size + 0x0f ) >> 4 );
+	undi_loader.UNDI_CS = fbms_seg;
+	fbms_seg -= ( ( undirom->data_size + 0x0f ) >> 4 );
+	undi_loader.UNDI_DS = fbms_seg;
+
+	/* Debug info */
+	DBGC ( undi, "UNDI %p loading UNDI ROM %p to CS %04x DS %04x for ",
+	       undi, undirom, undi_loader.UNDI_CS, undi_loader.UNDI_DS );
+	if ( undi->pci_busdevfn != UNDI_NO_PCI_BUSDEVFN ) {
+		unsigned int bus = ( undi->pci_busdevfn >> 8 );
+		unsigned int devfn = ( undi->pci_busdevfn & 0xff );
+		DBGC ( undi, "PCI %02x:%02x.%x\n",
+		       bus, PCI_SLOT ( devfn ), PCI_FUNC ( devfn ) );
+	}
+	if ( undi->isapnp_csn != UNDI_NO_ISAPNP_CSN ) {
+		DBGC ( undi, "ISAPnP(%04x) CSN %04x\n",
+		       undi->isapnp_read_port, undi->isapnp_csn );
+	}
+
+	/* Call loader */
+	undi_loader_entry = undirom->loader_entry;
+	__asm__ __volatile__ ( REAL_CODE ( "pushl %%ebp\n\t" /* gcc bug */
+					   "pushw %%ds\n\t"
+					   "pushw %%ax\n\t"
+					   "lcall *undi_loader_entry\n\t"
+					   "popl %%ebp\n\t" /* discard */
+					   "popl %%ebp\n\t" /* gcc bug */ )
+			       : "=a" ( exit )
+			       : "a" ( __from_data16 ( &undi_loader ) )
+			       : "ebx", "ecx", "edx", "esi", "edi" );
+
+	if ( exit != PXENV_EXIT_SUCCESS ) {
+		/* Clear entry point */
+		memset ( &undi_loader_entry, 0, sizeof ( undi_loader_entry ) );
+
+		rc = -EUNDILOAD ( undi_loader.Status );
+		DBGC ( undi, "UNDI %p loader failed: %s\n",
+		       undi, strerror ( rc ) );
+		return rc;
+	}
+
+	/* Populate PXE device structure */
+	undi->pxenv = undi_loader.PXENVptr;
+	undi->ppxe = undi_loader.PXEptr;
+	copy_from_real ( &ppxe, undi->ppxe.segment, undi->ppxe.offset,
+			 sizeof ( ppxe ) );
+	undi->entry = ppxe.EntryPointSP;
+	DBGC ( undi, "UNDI %p loaded PXENV+ %04x:%04x !PXE %04x:%04x "
+	       "entry %04x:%04x\n", undi, undi->pxenv.segment,
+	       undi->pxenv.offset, undi->ppxe.segment, undi->ppxe.offset,
+	       undi->entry.segment, undi->entry.offset );
+
+	/* Update free base memory counter */
+	undi->fbms = ( fbms_seg >> 6 );
+	set_fbms ( undi->fbms );
+	DBGC ( undi, "UNDI %p using [%d,%d) kB of base memory\n",
+	       undi, undi->fbms, undi->restore_fbms );
+
+	return 0;
+}
+
+/**
+ * Unload a pixie
+ *
+ * @v undi		UNDI device
+ * @ret rc		Return status code
+ *
+ * Erases the PXENV+ and !PXE signatures, and frees the used base
+ * memory (if possible).
+ */
+int undi_unload ( struct undi_device *undi ) {
+	static uint32_t dead = 0xdeaddead;
+
+	DBGC ( undi, "UNDI %p unloading\n", undi );
+
+	/* Clear entry point */
+	memset ( &undi_loader_entry, 0, sizeof ( undi_loader_entry ) );
+
+	/* Erase signatures */
+	if ( undi->pxenv.segment )
+		put_real ( dead, undi->pxenv.segment, undi->pxenv.offset );
+	if ( undi->ppxe.segment )
+		put_real ( dead, undi->ppxe.segment, undi->ppxe.offset );
+
+	/* Free base memory, if possible */
+	if ( undi->fbms == get_fbms() ) {
+		DBGC ( undi, "UNDI %p freeing [%d,%d) kB of base memory\n",
+		       undi, undi->fbms, undi->restore_fbms );
+		set_fbms ( undi->restore_fbms );
+		return 0;
+	} else {
+		DBGC ( undi, "UNDI %p leaking [%d,%d) kB of base memory\n",
+		       undi, undi->fbms, undi->restore_fbms );
+		return -EBUSY;
+	}
+}
diff --git a/roms/ipxe/src/arch/i386/drivers/net/undinet.c b/roms/ipxe/src/arch/i386/drivers/net/undinet.c
new file mode 100644
index 00000000..6450665f
--- /dev/null
+++ b/roms/ipxe/src/arch/i386/drivers/net/undinet.c
@@ -0,0 +1,822 @@
+/*
+ * Copyright (C) 2007 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 <unistd.h>
+#include <byteswap.h>
+#include <pxe.h>
+#include <realmode.h>
+#include <pic8259.h>
+#include <biosint.h>
+#include <pnpbios.h>
+#include <basemem_packet.h>
+#include <ipxe/io.h>
+#include <ipxe/iobuf.h>
+#include <ipxe/netdevice.h>
+#include <ipxe/if_ether.h>
+#include <ipxe/ethernet.h>
+#include <ipxe/profile.h>
+#include <undi.h>
+#include <undinet.h>
+#include <pxeparent.h>
+
+/** @file
+ *
+ * UNDI network device driver
+ *
+ */
+
+/** An UNDI NIC */
+struct undi_nic {
+	/** Device supports IRQs */
+	int irq_supported;
+	/** Assigned IRQ number */
+	unsigned int irq;
+	/** Currently processing ISR */
+	int isr_processing;
+	/** Bug workarounds */
+	int hacks;
+};
+
+/**
+ * @defgroup undi_hacks UNDI workarounds
+ * @{
+ */
+
+/** Work around Etherboot 5.4 bugs */
+#define UNDI_HACK_EB54		0x0001
+
+/** @} */
+
+/** Maximum number of times to retry PXENV_UNDI_INITIALIZE */
+#define UNDI_INITIALIZE_RETRY_MAX 10
+
+/** Delay between retries of PXENV_UNDI_INITIALIZE */
+#define UNDI_INITIALIZE_RETRY_DELAY_MS 200
+
+/** Maximum number of received packets per poll */
+#define UNDI_RX_QUOTA 4
+
+/** Alignment of received frame payload */
+#define UNDI_RX_ALIGN 16
+
+static void undinet_close ( struct net_device *netdev );
+
+/** Address of UNDI entry point */
+static SEGOFF16_t undinet_entry;
+
+/** Transmit profiler */
+static struct profiler undinet_tx_profiler __profiler =
+	{ .name = "undinet.tx" };
+
+/** Transmit call profiler */
+static struct profiler undinet_tx_call_profiler __profiler =
+	{ .name = "undinet.tx_call" };
+
+/** IRQ profiler */
+static struct profiler undinet_irq_profiler __profiler =
+	{ .name = "undinet.irq" };
+
+/** ISR call profiler */
+static struct profiler undinet_isr_call_profiler __profiler =
+	{ .name = "undinet.isr_call" };
+
+/** Receive profiler */
+static struct profiler undinet_rx_profiler __profiler =
+	{ .name = "undinet.rx" };
+
+/*****************************************************************************
+ *
+ * UNDI interrupt service routine
+ *
+ *****************************************************************************
+ */
+
+/**
+ * UNDI interrupt service routine
+ *
+ * The UNDI ISR increments a counter (@c trigger_count) and exits.
+ */
+extern void undiisr ( void );
+
+/** IRQ number */
+uint8_t __data16 ( undiisr_irq );
+#define undiisr_irq __use_data16 ( undiisr_irq )
+
+/** IRQ chain vector */
+struct segoff __data16 ( undiisr_next_handler );
+#define undiisr_next_handler __use_data16 ( undiisr_next_handler )
+
+/** IRQ trigger count */
+volatile uint8_t __data16 ( undiisr_trigger_count ) = 0;
+#define undiisr_trigger_count __use_data16 ( undiisr_trigger_count )
+
+/** Last observed trigger count */
+static unsigned int last_trigger_count = 0;
+
+/**
+ * Hook UNDI interrupt service routine
+ *
+ * @v irq		IRQ number
+ */
+static void undinet_hook_isr ( unsigned int irq ) {
+
+	assert ( irq <= IRQ_MAX );
+	assert ( undiisr_irq == 0 );
+
+	undiisr_irq = irq;
+	hook_bios_interrupt ( IRQ_INT ( irq ),
+			      ( ( unsigned int ) undiisr ),
+			      &undiisr_next_handler );
+}
+
+/**
+ * Unhook UNDI interrupt service routine
+ *
+ * @v irq		IRQ number
+ */
+static void undinet_unhook_isr ( unsigned int irq ) {
+
+	assert ( irq <= IRQ_MAX );
+
+	unhook_bios_interrupt ( IRQ_INT ( irq ),
+				( ( unsigned int ) undiisr ),
+				&undiisr_next_handler );
+	undiisr_irq = 0;
+}
+
+/**
+ * Test to see if UNDI ISR has been triggered
+ *
+ * @ret triggered	ISR has been triggered since last check
+ */
+static int undinet_isr_triggered ( void ) {
+	unsigned int this_trigger_count;
+
+	/* Read trigger_count.  Do this only once; it is volatile */
+	this_trigger_count = undiisr_trigger_count;
+
+	if ( this_trigger_count == last_trigger_count ) {
+		/* Not triggered */
+		return 0;
+	} else {
+		/* Triggered */
+		last_trigger_count = this_trigger_count;
+		return 1;
+	}
+}
+
+/*****************************************************************************
+ *
+ * UNDI network device interface
+ *
+ *****************************************************************************
+ */
+
+/** UNDI transmit buffer descriptor */
+static struct s_PXENV_UNDI_TBD __data16 ( undinet_tbd );
+#define undinet_tbd __use_data16 ( undinet_tbd )
+
+/** UNDI transmit destination address */
+static uint8_t __data16_array ( undinet_destaddr, [ETH_ALEN] );
+#define undinet_destaddr __use_data16 ( undinet_destaddr )
+
+/**
+ * Transmit packet
+ *
+ * @v netdev		Network device
+ * @v iobuf		I/O buffer
+ * @ret rc		Return status code
+ */
+static int undinet_transmit ( struct net_device *netdev,
+			      struct io_buffer *iobuf ) {
+	struct undi_nic *undinic = netdev->priv;
+	struct s_PXENV_UNDI_TRANSMIT undi_transmit;
+	const void *ll_dest;
+	const void *ll_source;
+	uint16_t net_proto;
+	unsigned int flags;
+	uint8_t protocol;
+	size_t len;
+	int rc;
+
+	/* Start profiling */
+	profile_start ( &undinet_tx_profiler );
+
+	/* Technically, we ought to make sure that the previous
+	 * transmission has completed before we re-use the buffer.
+	 * However, many PXE stacks (including at least some Intel PXE
+	 * stacks and Etherboot 5.4) fail to generate TX completions.
+	 * In practice this won't be a problem, since our TX datapath
+	 * has a very low packet volume and we can get away with
+	 * assuming that a TX will be complete by the time we want to
+	 * transmit the next packet.
+	 */
+
+	/* Some PXE stacks are unable to cope with P_UNKNOWN, and will
+	 * always try to prepend a link-layer header.  Work around
+	 * these stacks by stripping the existing link-layer header
+	 * and allowing the PXE stack to (re)construct the link-layer
+	 * header itself.
+	 */
+	if ( ( rc = eth_pull ( netdev, iobuf, &ll_dest, &ll_source,
+			       &net_proto, &flags ) ) != 0 ) {
+		DBGC ( undinic, "UNDINIC %p could not strip Ethernet header: "
+		       "%s\n", undinic, strerror ( rc ) );
+		return rc;
+	}
+	memcpy ( undinet_destaddr, ll_dest, sizeof ( undinet_destaddr ) );
+	switch ( net_proto ) {
+	case htons ( ETH_P_IP ) :
+		protocol = P_IP;
+		break;
+	case htons ( ETH_P_ARP ) :
+		protocol = P_ARP;
+		break;
+	case htons ( ETH_P_RARP ) :
+		protocol = P_RARP;
+		break;
+	default:
+		/* Unknown protocol; restore the original link-layer header */
+		iob_push ( iobuf, sizeof ( struct ethhdr ) );
+		protocol = P_UNKNOWN;
+		break;
+	}
+
+	/* Copy packet to UNDI I/O buffer */
+	len = iob_len ( iobuf );
+	if ( len > sizeof ( basemem_packet ) )
+		len = sizeof ( basemem_packet );
+	memcpy ( &basemem_packet, iobuf->data, len );
+
+	/* Create PXENV_UNDI_TRANSMIT data structure */
+	memset ( &undi_transmit, 0, sizeof ( undi_transmit ) );
+	undi_transmit.Protocol = protocol;
+	undi_transmit.XmitFlag = ( ( flags & LL_BROADCAST ) ?
+				   XMT_BROADCAST : XMT_DESTADDR );
+	undi_transmit.DestAddr.segment = rm_ds;
+	undi_transmit.DestAddr.offset = __from_data16 ( &undinet_destaddr );
+	undi_transmit.TBD.segment = rm_ds;
+	undi_transmit.TBD.offset = __from_data16 ( &undinet_tbd );
+
+	/* Create PXENV_UNDI_TBD data structure */
+	undinet_tbd.ImmedLength = len;
+	undinet_tbd.Xmit.segment = rm_ds;
+	undinet_tbd.Xmit.offset = __from_data16 ( basemem_packet );
+
+	/* Issue PXE API call */
+	profile_start ( &undinet_tx_call_profiler );
+	if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_TRANSMIT,
+				     &undi_transmit,
+				     sizeof ( undi_transmit ) ) ) != 0 )
+		goto done;
+	profile_stop ( &undinet_tx_call_profiler );
+
+	/* Free I/O buffer */
+	netdev_tx_complete ( netdev, iobuf );
+	profile_stop ( &undinet_tx_profiler );
+ done:
+	return rc;
+}
+
+/** 
+ * Poll for received packets
+ *
+ * @v netdev		Network device
+ *
+ * Fun, fun, fun.  UNDI drivers don't use polling; they use
+ * interrupts.  We therefore cheat and pretend that an interrupt has
+ * occurred every time undinet_poll() is called.  This isn't too much
+ * of a hack; PCI devices share IRQs and so the first thing that a
+ * proper ISR should do is call PXENV_UNDI_ISR to determine whether or
+ * not the UNDI NIC generated the interrupt; there is no harm done by
+ * spurious calls to PXENV_UNDI_ISR.  Similarly, we wouldn't be
+ * handling them any more rapidly than the usual rate of
+ * undinet_poll() being called even if we did implement a full ISR.
+ * So it should work.  Ha!
+ *
+ * Addendum (21/10/03).  Some cards don't play nicely with this trick,
+ * so instead of doing it the easy way we have to go to all the hassle
+ * of installing a genuine interrupt service routine and dealing with
+ * the wonderful 8259 Programmable Interrupt Controller.  Joy.
+ *
+ * Addendum (10/07/07).  When doing things such as iSCSI boot, in
+ * which we have to co-operate with a running OS, we can't get away
+ * with the "ISR-just-increments-a-counter-and-returns" trick at all,
+ * because it involves tying up the PIC for far too long, and other
+ * interrupt-dependent components (e.g. local disks) start breaking.
+ * We therefore implement a "proper" ISR which calls PXENV_UNDI_ISR
+ * from within interrupt context in order to deassert the device
+ * interrupt, and sends EOI if applicable.
+ */
+static void undinet_poll ( struct net_device *netdev ) {
+	struct undi_nic *undinic = netdev->priv;
+	struct s_PXENV_UNDI_ISR undi_isr;
+	struct io_buffer *iobuf = NULL;
+	unsigned int quota = UNDI_RX_QUOTA;
+	size_t len;
+	size_t reserve_len;
+	size_t frag_len;
+	size_t max_frag_len;
+	int rc;
+
+	if ( ! undinic->isr_processing ) {
+		/* Allow interrupt to occur.  Do this even if
+		 * interrupts are not known to be supported, since
+		 * some cards erroneously report that they do not
+		 * support interrupts.
+		 */
+		if ( ! undinet_isr_triggered() ) {
+			/* Allow interrupt to occur */
+			profile_start ( &undinet_irq_profiler );
+			__asm__ __volatile__ ( "sti\n\t"
+					       "nop\n\t"
+					       "nop\n\t"
+					       "cli\n\t" );
+			profile_stop ( &undinet_irq_profiler );
+
+			/* If interrupts are known to be supported,
+			 * then do nothing on this poll; wait for the
+			 * interrupt to be triggered.
+			 */
+			if ( undinic->irq_supported )
+				return;
+		}
+
+		/* Start ISR processing */
+		undinic->isr_processing = 1;
+		undi_isr.FuncFlag = PXENV_UNDI_ISR_IN_PROCESS;
+	} else {
+		/* Continue ISR processing */
+		undi_isr.FuncFlag = PXENV_UNDI_ISR_IN_GET_NEXT;
+	}
+
+	/* Run through the ISR loop */
+	while ( quota ) {
+		profile_start ( &undinet_isr_call_profiler );
+		if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_ISR,
+					     &undi_isr,
+					     sizeof ( undi_isr ) ) ) != 0 ) {
+			netdev_rx_err ( netdev, NULL, rc );
+			break;
+		}
+		profile_stop ( &undinet_isr_call_profiler );
+		switch ( undi_isr.FuncFlag ) {
+		case PXENV_UNDI_ISR_OUT_TRANSMIT:
+			/* We don't care about transmit completions */
+			break;
+		case PXENV_UNDI_ISR_OUT_RECEIVE:
+			/* Packet fragment received */
+			profile_start ( &undinet_rx_profiler );
+			len = undi_isr.FrameLength;
+			frag_len = undi_isr.BufferLength;
+			reserve_len = ( -undi_isr.FrameHeaderLength &
+					( UNDI_RX_ALIGN - 1 ) );
+			if ( ( len == 0 ) || ( len < frag_len ) ) {
+				/* Don't laugh.  VMWare does it. */
+				DBGC ( undinic, "UNDINIC %p reported insane "
+				       "fragment (%zd of %zd bytes)\n",
+				       undinic, frag_len, len );
+				netdev_rx_err ( netdev, NULL, -EINVAL );
+				break;
+			}
+			if ( ! iobuf ) {
+				iobuf = alloc_iob ( reserve_len + len );
+				if ( ! iobuf ) {
+					DBGC ( undinic, "UNDINIC %p could not "
+					       "allocate %zd bytes for RX "
+					       "buffer\n", undinic, len );
+					/* Fragment will be dropped */
+					netdev_rx_err ( netdev, NULL, -ENOMEM );
+					goto done;
+				}
+				iob_reserve ( iobuf, reserve_len );
+			}
+			max_frag_len = iob_tailroom ( iobuf );
+			if ( frag_len > max_frag_len ) {
+				DBGC ( undinic, "UNDINIC %p fragment too big "
+				       "(%zd+%zd does not fit into %zd)\n",
+				       undinic, iob_len ( iobuf ), frag_len,
+				       ( iob_len ( iobuf ) + max_frag_len ) );
+				frag_len = max_frag_len;
+			}
+			copy_from_real ( iob_put ( iobuf, frag_len ),
+					 undi_isr.Frame.segment,
+					 undi_isr.Frame.offset, frag_len );
+			if ( iob_len ( iobuf ) == len ) {
+				/* Whole packet received; deliver it */
+				netdev_rx ( netdev, iob_disown ( iobuf ) );
+				quota--;
+				/* Etherboot 5.4 fails to return all packets
+				 * under mild load; pretend it retriggered.
+				 */
+				if ( undinic->hacks & UNDI_HACK_EB54 )
+					--last_trigger_count;
+			}
+			profile_stop ( &undinet_rx_profiler );
+			break;
+		case PXENV_UNDI_ISR_OUT_DONE:
+			/* Processing complete */
+			undinic->isr_processing = 0;
+			goto done;
+		default:
+			/* Should never happen.  VMWare does it routinely. */
+			DBGC ( undinic, "UNDINIC %p ISR returned invalid "
+			       "FuncFlag %04x\n", undinic, undi_isr.FuncFlag );
+			undinic->isr_processing = 0;
+			goto done;
+		}
+		undi_isr.FuncFlag = PXENV_UNDI_ISR_IN_GET_NEXT;
+	}
+
+ done:
+	if ( iobuf ) {
+		DBGC ( undinic, "UNDINIC %p returned incomplete packet "
+		       "(%zd of %zd)\n", undinic, iob_len ( iobuf ),
+		       ( iob_len ( iobuf ) + iob_tailroom ( iobuf ) ) );
+		netdev_rx_err ( netdev, iobuf, -EINVAL );
+	}
+}
+
+/**
+ * Open NIC
+ *
+ * @v netdev		Net device
+ * @ret rc		Return status code
+ */
+static int undinet_open ( struct net_device *netdev ) {
+	struct undi_nic *undinic = netdev->priv;
+	struct s_PXENV_UNDI_SET_STATION_ADDRESS undi_set_address;
+	struct s_PXENV_UNDI_OPEN undi_open;
+	int rc;
+
+	/* Hook interrupt service routine and enable interrupt if applicable */
+	if ( undinic->irq ) {
+		undinet_hook_isr ( undinic->irq );
+		enable_irq ( undinic->irq );
+		send_eoi ( undinic->irq );
+	}
+
+	/* Set station address.  Required for some PXE stacks; will
+	 * spuriously fail on others.  Ignore failures.  We only ever
+	 * use it to set the MAC address to the card's permanent value
+	 * anyway.
+	 */
+	memcpy ( undi_set_address.StationAddress, netdev->ll_addr,
+		 sizeof ( undi_set_address.StationAddress ) );
+	pxeparent_call ( undinet_entry, PXENV_UNDI_SET_STATION_ADDRESS,
+			 &undi_set_address, sizeof ( undi_set_address ) );
+
+	/* Open NIC.  We ask for promiscuous operation, since it's the
+	 * only way to ask for all multicast addresses.  On any
+	 * switched network, it shouldn't really make a difference to
+	 * performance.
+	 */
+	memset ( &undi_open, 0, sizeof ( undi_open ) );
+	undi_open.PktFilter = ( FLTR_DIRECTED | FLTR_BRDCST | FLTR_PRMSCS );
+	if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_OPEN,
+				     &undi_open, sizeof ( undi_open ) ) ) != 0 )
+		goto err;
+
+	DBGC ( undinic, "UNDINIC %p opened\n", undinic );
+	return 0;
+
+ err:
+	undinet_close ( netdev );
+	return rc;
+}
+
+/**
+ * Close NIC
+ *
+ * @v netdev		Net device
+ */
+static void undinet_close ( struct net_device *netdev ) {
+	struct undi_nic *undinic = netdev->priv;
+	struct s_PXENV_UNDI_ISR undi_isr;
+	struct s_PXENV_UNDI_CLOSE undi_close;
+	int rc;
+
+	/* Ensure ISR has exited cleanly */
+	while ( undinic->isr_processing ) {
+		undi_isr.FuncFlag = PXENV_UNDI_ISR_IN_GET_NEXT;
+		if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_ISR,
+					     &undi_isr,
+					     sizeof ( undi_isr ) ) ) != 0 )
+			break;
+		switch ( undi_isr.FuncFlag ) {
+		case PXENV_UNDI_ISR_OUT_TRANSMIT:
+		case PXENV_UNDI_ISR_OUT_RECEIVE:
+			/* Continue draining */
+			break;
+		default:
+			/* Stop processing */
+			undinic->isr_processing = 0;
+			break;
+		}
+	}
+
+	/* Close NIC */
+	pxeparent_call ( undinet_entry, PXENV_UNDI_CLOSE,
+			 &undi_close, sizeof ( undi_close ) );
+
+	/* Disable interrupt and unhook ISR if applicable */
+	if ( undinic->irq ) {
+		disable_irq ( undinic->irq );
+		undinet_unhook_isr ( undinic->irq );
+	}
+
+	DBGC ( undinic, "UNDINIC %p closed\n", undinic );
+}
+
+/**
+ * Enable/disable interrupts
+ *
+ * @v netdev		Net device
+ * @v enable		Interrupts should be enabled
+ */
+static void undinet_irq ( struct net_device *netdev, int enable ) {
+	struct undi_nic *undinic = netdev->priv;
+
+	/* Cannot support interrupts yet */
+	DBGC ( undinic, "UNDINIC %p cannot %s interrupts\n",
+	       undinic, ( enable ? "enable" : "disable" ) );
+}
+
+/** UNDI network device operations */
+static struct net_device_operations undinet_operations = {
+	.open		= undinet_open,
+	.close		= undinet_close,
+	.transmit	= undinet_transmit,
+	.poll		= undinet_poll,
+	.irq   		= undinet_irq,
+};
+
+/** A device with broken support for generating interrupts */
+struct undinet_irq_broken {
+	/** PCI vendor ID */
+	uint16_t pci_vendor;
+	/** PCI device ID */
+	uint16_t pci_device;
+};
+
+/**
+ * List of devices with broken support for generating interrupts
+ *
+ * Some PXE stacks are known to claim that IRQs are supported, but
+ * then never generate interrupts.  No satisfactory solution has been
+ * found to this problem; the workaround is to add the PCI vendor and
+ * device IDs to this list.  This is something of a hack, since it
+ * will generate false positives for identical devices with a working
+ * PXE stack (e.g. those that have been reflashed with iPXE), but it's
+ * an improvement on the current situation.
+ */
+static const struct undinet_irq_broken undinet_irq_broken_list[] = {
+	/* HP XX70x laptops */
+	{ .pci_vendor = 0x8086, .pci_device = 0x1502 },
+	{ .pci_vendor = 0x8086, .pci_device = 0x1503 },
+};
+
+/**
+ * Check for devices with broken support for generating interrupts
+ *
+ * @v undi		UNDI device
+ * @ret irq_is_broken	Interrupt support is broken; no interrupts are generated
+ */
+static int undinet_irq_is_broken ( struct undi_device *undi ) {
+	const struct undinet_irq_broken *broken;
+	unsigned int i;
+
+	for ( i = 0 ; i < ( sizeof ( undinet_irq_broken_list ) /
+			    sizeof ( undinet_irq_broken_list[0] ) ) ; i++ ) {
+		broken = &undinet_irq_broken_list[i];
+		if ( ( undi->dev.desc.bus_type == BUS_TYPE_PCI ) &&
+		     ( undi->dev.desc.vendor == broken->pci_vendor ) &&
+		     ( undi->dev.desc.device == broken->pci_device ) ) {
+			return 1;
+		}
+	}
+	return 0;
+}
+
+/**
+ * Probe UNDI device
+ *
+ * @v undi		UNDI device
+ * @ret rc		Return status code
+ */
+int undinet_probe ( struct undi_device *undi ) {
+	struct net_device *netdev;
+	struct undi_nic *undinic;
+	struct s_PXENV_START_UNDI start_undi;
+	struct s_PXENV_UNDI_STARTUP undi_startup;
+	struct s_PXENV_UNDI_INITIALIZE undi_init;
+	struct s_PXENV_UNDI_GET_INFORMATION undi_info;
+	struct s_PXENV_UNDI_GET_IFACE_INFO undi_iface;
+	struct s_PXENV_UNDI_SHUTDOWN undi_shutdown;
+	struct s_PXENV_UNDI_CLEANUP undi_cleanup;
+	struct s_PXENV_STOP_UNDI stop_undi;
+	unsigned int retry;
+	int rc;
+
+	/* Allocate net device */
+	netdev = alloc_etherdev ( sizeof ( *undinic ) );
+	if ( ! netdev )
+		return -ENOMEM;
+	netdev_init ( netdev, &undinet_operations );
+	undinic = netdev->priv;
+	undi_set_drvdata ( undi, netdev );
+	netdev->dev = &undi->dev;
+	memset ( undinic, 0, sizeof ( *undinic ) );
+	undinet_entry = undi->entry;
+	DBGC ( undinic, "UNDINIC %p using UNDI %p\n", undinic, undi );
+
+	/* Hook in UNDI stack */
+	if ( ! ( undi->flags & UNDI_FL_STARTED ) ) {
+		memset ( &start_undi, 0, sizeof ( start_undi ) );
+		start_undi.AX = undi->pci_busdevfn;
+		start_undi.BX = undi->isapnp_csn;
+		start_undi.DX = undi->isapnp_read_port;
+		start_undi.ES = BIOS_SEG;
+		start_undi.DI = find_pnp_bios();
+		if ( ( rc = pxeparent_call ( undinet_entry, PXENV_START_UNDI,
+					     &start_undi,
+					     sizeof ( start_undi ) ) ) != 0 )
+			goto err_start_undi;
+	}
+	undi->flags |= UNDI_FL_STARTED;
+
+	/* Bring up UNDI stack */
+	if ( ! ( undi->flags & UNDI_FL_INITIALIZED ) ) {
+		memset ( &undi_startup, 0, sizeof ( undi_startup ) );
+		if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_STARTUP,
+					     &undi_startup,
+					     sizeof ( undi_startup ) ) ) != 0 )
+			goto err_undi_startup;
+		/* On some PXE stacks, PXENV_UNDI_INITIALIZE may fail
+		 * due to a transient condition (e.g. media test
+		 * failing because the link has only just come out of
+		 * reset).  We may therefore need to retry this call
+		 * several times.
+		 */
+		for ( retry = 0 ; ; ) {
+			memset ( &undi_init, 0, sizeof ( undi_init ) );
+			if ( ( rc = pxeparent_call ( undinet_entry,
+						     PXENV_UNDI_INITIALIZE,
+						     &undi_init,
+						     sizeof ( undi_init ))) ==0)
+				break;
+			if ( ++retry > UNDI_INITIALIZE_RETRY_MAX )
+				goto err_undi_initialize;
+			DBGC ( undinic, "UNDINIC %p retrying "
+			       "PXENV_UNDI_INITIALIZE (retry %d)\n",
+			       undinic, retry );
+			/* Delay to allow link to settle if necessary */
+			mdelay ( UNDI_INITIALIZE_RETRY_DELAY_MS );
+		}
+	}
+	undi->flags |= UNDI_FL_INITIALIZED;
+
+	/* Get device information */
+	memset ( &undi_info, 0, sizeof ( undi_info ) );
+	if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_GET_INFORMATION,
+				     &undi_info, sizeof ( undi_info ) ) ) != 0 )
+		goto err_undi_get_information;
+	memcpy ( netdev->hw_addr, undi_info.PermNodeAddress, ETH_ALEN );
+	memcpy ( netdev->ll_addr, undi_info.CurrentNodeAddress, ETH_ALEN );
+	undinic->irq = undi_info.IntNumber;
+	if ( undinic->irq > IRQ_MAX ) {
+		DBGC ( undinic, "UNDINIC %p has invalid IRQ %d\n",
+		       undinic, undinic->irq );
+		rc = -EINVAL;
+		goto err_bad_irq;
+	}
+	DBGC ( undinic, "UNDINIC %p has MAC address %s and IRQ %d\n",
+	       undinic, eth_ntoa ( netdev->hw_addr ), undinic->irq );
+
+	/* Get interface information */
+	memset ( &undi_iface, 0, sizeof ( undi_iface ) );
+	if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_GET_IFACE_INFO,
+				     &undi_iface,
+				     sizeof ( undi_iface ) ) ) != 0 )
+		goto err_undi_get_iface_info;
+	DBGC ( undinic, "UNDINIC %p has type %s, speed %d, flags %08x\n",
+	       undinic, undi_iface.IfaceType, undi_iface.LinkSpeed,
+	       undi_iface.ServiceFlags );
+	if ( ( undi_iface.ServiceFlags & SUPPORTED_IRQ ) &&
+	     ( undinic->irq != 0 ) ) {
+		undinic->irq_supported = 1;
+	}
+	DBGC ( undinic, "UNDINIC %p using %s mode\n", undinic,
+	       ( undinic->irq_supported ? "interrupt" : "polling" ) );
+	if ( strncmp ( ( ( char * ) undi_iface.IfaceType ), "Etherboot",
+		       sizeof ( undi_iface.IfaceType ) ) == 0 ) {
+		DBGC ( undinic, "UNDINIC %p Etherboot 5.4 workaround enabled\n",
+		       undinic );
+		undinic->hacks |= UNDI_HACK_EB54;
+	}
+	if ( undinet_irq_is_broken ( undi ) ) {
+		DBGC ( undinic, "UNDINIC %p forcing polling mode due to "
+		       "broken interrupts\n", undinic );
+		undinic->irq_supported = 0;
+	}
+
+	/* Register network device */
+	if ( ( rc = register_netdev ( netdev ) ) != 0 )
+		goto err_register;
+
+	/* Mark as link up; we don't handle link state */
+	netdev_link_up ( netdev );
+
+	DBGC ( undinic, "UNDINIC %p added\n", undinic );
+	return 0;
+
+ err_register:
+ err_undi_get_iface_info:
+ err_bad_irq:
+ err_undi_get_information:
+ err_undi_initialize:
+	/* Shut down UNDI stack */
+	memset ( &undi_shutdown, 0, sizeof ( undi_shutdown ) );
+	pxeparent_call ( undinet_entry, PXENV_UNDI_SHUTDOWN, &undi_shutdown,
+			 sizeof ( undi_shutdown ) );
+	memset ( &undi_cleanup, 0, sizeof ( undi_cleanup ) );
+	pxeparent_call ( undinet_entry, PXENV_UNDI_CLEANUP, &undi_cleanup,
+			 sizeof ( undi_cleanup ) );
+	undi->flags &= ~UNDI_FL_INITIALIZED;
+ err_undi_startup:
+	/* Unhook UNDI stack */
+	memset ( &stop_undi, 0, sizeof ( stop_undi ) );
+	pxeparent_call ( undinet_entry, PXENV_STOP_UNDI, &stop_undi,
+			 sizeof ( stop_undi ) );
+	undi->flags &= ~UNDI_FL_STARTED;
+ err_start_undi:
+	netdev_nullify ( netdev );
+	netdev_put ( netdev );
+	undi_set_drvdata ( undi, NULL );
+	return rc;
+}
+
+/**
+ * Remove UNDI device
+ *
+ * @v undi		UNDI device
+ */
+void undinet_remove ( struct undi_device *undi ) {
+	struct net_device *netdev = undi_get_drvdata ( undi );
+	struct undi_nic *undinic = netdev->priv;
+	struct s_PXENV_UNDI_SHUTDOWN undi_shutdown;
+	struct s_PXENV_UNDI_CLEANUP undi_cleanup;
+	struct s_PXENV_STOP_UNDI stop_undi;
+
+	/* Unregister net device */
+	unregister_netdev ( netdev );
+
+	/* If we are preparing for an OS boot, or if we cannot exit
+	 * via the PXE stack, then shut down the PXE stack.
+	 */
+	if ( ! ( undi->flags & UNDI_FL_KEEP_ALL ) ) {
+
+		/* Shut down UNDI stack */
+		memset ( &undi_shutdown, 0, sizeof ( undi_shutdown ) );
+		pxeparent_call ( undinet_entry, PXENV_UNDI_SHUTDOWN,
+				 &undi_shutdown, sizeof ( undi_shutdown ) );
+		memset ( &undi_cleanup, 0, sizeof ( undi_cleanup ) );
+		pxeparent_call ( undinet_entry, PXENV_UNDI_CLEANUP,
+				 &undi_cleanup, sizeof ( undi_cleanup ) );
+		undi->flags &= ~UNDI_FL_INITIALIZED;
+
+		/* Unhook UNDI stack */
+		memset ( &stop_undi, 0, sizeof ( stop_undi ) );
+		pxeparent_call ( undinet_entry, PXENV_STOP_UNDI, &stop_undi,
+				 sizeof ( stop_undi ) );
+		undi->flags &= ~UNDI_FL_STARTED;
+	}
+
+	/* Clear entry point */
+	memset ( &undinet_entry, 0, sizeof ( undinet_entry ) );
+
+	/* Free network device */
+	netdev_nullify ( netdev );
+	netdev_put ( netdev );
+
+	DBGC ( undinic, "UNDINIC %p removed\n", undinic );
+}
diff --git a/roms/ipxe/src/arch/i386/drivers/net/undionly.c b/roms/ipxe/src/arch/i386/drivers/net/undionly.c
new file mode 100644
index 00000000..028fac5d
--- /dev/null
+++ b/roms/ipxe/src/arch/i386/drivers/net/undionly.c
@@ -0,0 +1,138 @@
+/*
+ * Copyright (C) 2007 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 <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <ipxe/device.h>
+#include <ipxe/init.h>
+#include <ipxe/pci.h>
+#include <undi.h>
+#include <undinet.h>
+#include <undipreload.h>
+
+/** @file
+ *
+ * "Pure" UNDI driver
+ *
+ * This is the UNDI driver without explicit support for PCI or any
+ * other bus type.  It is capable only of using the preloaded UNDI
+ * device.  It must not be combined in an image with any other
+ * drivers.
+ *
+ * If you want a PXE-loadable image that contains only the UNDI
+ * driver, build "bin/undionly.kpxe".
+ *
+ * If you want any other image format, or any other drivers in
+ * addition to the UNDI driver, build e.g. "bin/undi.dsk".
+ */
+
+/**
+ * Probe UNDI root bus
+ *
+ * @v rootdev		UNDI bus root device
+ *
+ * Scans the UNDI bus for devices and registers all devices it can
+ * find.
+ */
+static int undibus_probe ( struct root_device *rootdev ) {
+	struct undi_device *undi = &preloaded_undi;
+	int rc;
+
+	/* Check for a valie preloaded UNDI device */
+	if ( ! undi->entry.segment ) {
+		DBG ( "No preloaded UNDI device found!\n" );
+		return -ENODEV;
+	}
+
+	/* Add to device hierarchy */
+	undi->dev.driver_name = "undionly";
+	if ( undi->pci_busdevfn != UNDI_NO_PCI_BUSDEVFN ) {
+		undi->dev.desc.bus_type = BUS_TYPE_PCI;
+		undi->dev.desc.location = undi->pci_busdevfn;
+		undi->dev.desc.vendor = undi->pci_vendor;
+		undi->dev.desc.device = undi->pci_device;
+		snprintf ( undi->dev.name, sizeof ( undi->dev.name ),
+			   "UNDI-PCI%02x:%02x.%x",
+			   PCI_BUS ( undi->pci_busdevfn ),
+			   PCI_SLOT ( undi->pci_busdevfn ),
+			   PCI_FUNC ( undi->pci_busdevfn ) );
+	} else if ( undi->isapnp_csn != UNDI_NO_ISAPNP_CSN ) {
+		undi->dev.desc.bus_type = BUS_TYPE_ISAPNP;
+		snprintf ( undi->dev.name, sizeof ( undi->dev.name ),
+			   "UNDI-ISAPNP" );
+	}
+	undi->dev.parent = &rootdev->dev;
+	list_add ( &undi->dev.siblings, &rootdev->dev.children);
+	INIT_LIST_HEAD ( &undi->dev.children );
+
+	/* Create network device */
+	if ( ( rc = undinet_probe ( undi ) ) != 0 )
+		goto err;
+
+	return 0;
+
+ err:
+	list_del ( &undi->dev.siblings );
+	return rc;
+}
+
+/**
+ * Remove UNDI root bus
+ *
+ * @v rootdev		UNDI bus root device
+ */
+static void undibus_remove ( struct root_device *rootdev __unused ) {
+	struct undi_device *undi = &preloaded_undi;
+
+	undinet_remove ( undi );
+	list_del ( &undi->dev.siblings );
+}
+
+/** UNDI bus root device driver */
+static struct root_driver undi_root_driver = {
+	.probe = undibus_probe,
+	.remove = undibus_remove,
+};
+
+/** UNDI bus root device */
+struct root_device undi_root_device __root_device = {
+	.dev = { .name = "UNDI" },
+	.driver = &undi_root_driver,
+};
+
+/**
+ * Prepare for exit
+ *
+ * @v booting		System is shutting down for OS boot
+ */
+static void undionly_shutdown ( int booting ) {
+	/* If we are shutting down to boot an OS, clear the "keep PXE
+	 * stack" flag.
+	 */
+	if ( booting )
+		preloaded_undi.flags &= ~UNDI_FL_KEEP_ALL;
+}
+
+struct startup_fn startup_undionly __startup_fn ( STARTUP_LATE ) = {
+	.shutdown = undionly_shutdown,
+};
diff --git a/roms/ipxe/src/arch/i386/drivers/net/undipreload.c b/roms/ipxe/src/arch/i386/drivers/net/undipreload.c
new file mode 100644
index 00000000..81d7a80e
--- /dev/null
+++ b/roms/ipxe/src/arch/i386/drivers/net/undipreload.c
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2007 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 <realmode.h>
+#include <undipreload.h>
+
+/** @file
+ *
+ * Preloaded UNDI stack
+ *
+ */
+
+/**
+ * Preloaded UNDI device
+ *
+ * This is the UNDI device that was present when Etherboot started
+ * execution (i.e. when loading a .kpxe image).  The first driver to
+ * claim this device must zero out this data structure.
+ */
+struct undi_device __data16 ( preloaded_undi );
diff --git a/roms/ipxe/src/arch/i386/drivers/net/undirom.c b/roms/ipxe/src/arch/i386/drivers/net/undirom.c
new file mode 100644
index 00000000..b54c6170
--- /dev/null
+++ b/roms/ipxe/src/arch/i386/drivers/net/undirom.c
@@ -0,0 +1,235 @@
+/*
+ * Copyright (C) 2007 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 <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <pxe.h>
+#include <realmode.h>
+#include <undirom.h>
+
+/** @file
+ *
+ * UNDI expansion ROMs
+ *
+ */
+
+/** List of all UNDI ROMs */
+static LIST_HEAD ( undiroms );
+
+/**
+ * Parse PXE ROM ID structure
+ *
+ * @v undirom		UNDI ROM
+ * @v pxeromid		Offset within ROM to PXE ROM ID structure
+ * @ret rc		Return status code
+ */
+static int undirom_parse_pxeromid ( struct undi_rom *undirom,
+				   unsigned int pxeromid ) {
+	struct undi_rom_id undi_rom_id;
+	unsigned int undiloader;
+
+	DBGC ( undirom, "UNDIROM %p has PXE ROM ID at %04x:%04x\n", undirom,
+	       undirom->rom_segment, pxeromid );
+
+	/* Read PXE ROM ID structure and verify */
+	copy_from_real ( &undi_rom_id, undirom->rom_segment, pxeromid,
+			 sizeof ( undi_rom_id ) );
+	if ( undi_rom_id.Signature != UNDI_ROM_ID_SIGNATURE ) {
+		DBGC ( undirom, "UNDIROM %p has bad PXE ROM ID signature "
+		       "%08x\n", undirom, undi_rom_id.Signature );
+		return -EINVAL;
+	}
+
+	/* Check for UNDI loader */
+	undiloader = undi_rom_id.UNDILoader;
+	if ( ! undiloader ) {
+		DBGC ( undirom, "UNDIROM %p has no UNDI loader\n", undirom );
+		return -EINVAL;
+	}
+
+	/* Fill in UNDI ROM loader fields */
+	undirom->loader_entry.segment = undirom->rom_segment;
+	undirom->loader_entry.offset = undiloader;
+	undirom->code_size = undi_rom_id.CodeSize;
+	undirom->data_size = undi_rom_id.DataSize;
+
+	DBGC ( undirom, "UNDIROM %p has UNDI loader at %04x:%04x "
+	       "(code %04zx data %04zx)\n", undirom,
+	       undirom->loader_entry.segment, undirom->loader_entry.offset,
+	       undirom->code_size, undirom->data_size );
+	return 0;
+}
+
+/**
+ * Parse PCI expansion header
+ *
+ * @v undirom		UNDI ROM
+ * @v pcirheader	Offset within ROM to PCI expansion header
+ */
+static int undirom_parse_pcirheader ( struct undi_rom *undirom,
+				     unsigned int pcirheader ) {
+	struct pcir_header pcir_header;
+
+	DBGC ( undirom, "UNDIROM %p has PCI expansion header at %04x:%04x\n",
+	       undirom, undirom->rom_segment, pcirheader );
+
+	/* Read PCI expansion header and verify */
+	copy_from_real ( &pcir_header, undirom->rom_segment, pcirheader,
+			 sizeof ( pcir_header ) );
+	if ( pcir_header.signature != PCIR_SIGNATURE ) {
+		DBGC ( undirom, "UNDIROM %p has bad PCI expansion header "
+		       "signature %08x\n", undirom, pcir_header.signature );
+		return -EINVAL;
+	}
+
+	/* Fill in UNDI ROM PCI device fields */
+	undirom->bus_type = PCI_NIC;
+	undirom->bus_id.pci.vendor_id = pcir_header.vendor_id;
+	undirom->bus_id.pci.device_id = pcir_header.device_id;
+
+	DBGC ( undirom, "UNDIROM %p is for PCI devices %04x:%04x\n", undirom,
+	       undirom->bus_id.pci.vendor_id, undirom->bus_id.pci.device_id );
+	return 0;
+	
+}
+
+/**
+ * Probe UNDI ROM
+ *
+ * @v rom_segment	ROM segment address
+ * @ret rc		Return status code
+ */
+static int undirom_probe ( unsigned int rom_segment ) {
+	struct undi_rom *undirom = NULL;
+	struct undi_rom_header romheader;
+	size_t rom_len;
+	unsigned int pxeromid;
+	unsigned int pcirheader;
+	int rc;
+
+	/* Read expansion ROM header and verify */
+	copy_from_real ( &romheader, rom_segment, 0, sizeof ( romheader ) );
+	if ( romheader.Signature != ROM_SIGNATURE ) {
+		rc = -EINVAL;
+		goto err;
+	}
+	rom_len = ( romheader.ROMLength * 512 );
+
+	/* Allocate memory for UNDI ROM */
+	undirom = zalloc ( sizeof ( *undirom ) );
+	if ( ! undirom ) {
+		DBG ( "Could not allocate UNDI ROM structure\n" );
+		rc = -ENOMEM;
+		goto err;
+	}
+	DBGC ( undirom, "UNDIROM %p trying expansion ROM at %04x:0000 "
+	       "(%zdkB)\n", undirom, rom_segment, ( rom_len / 1024 ) );
+	undirom->rom_segment = rom_segment;
+
+	/* Check for and parse PXE ROM ID */
+	pxeromid = romheader.PXEROMID;
+	if ( ! pxeromid ) {
+		DBGC ( undirom, "UNDIROM %p has no PXE ROM ID\n", undirom );
+		rc = -EINVAL;
+		goto err;
+	}
+	if ( pxeromid > rom_len ) {
+		DBGC ( undirom, "UNDIROM %p PXE ROM ID outside ROM\n",
+		       undirom );
+		rc = -EINVAL;
+		goto err;
+	}
+	if ( ( rc = undirom_parse_pxeromid ( undirom, pxeromid ) ) != 0 )
+		goto err;
+
+	/* Parse PCIR header, if present */
+	pcirheader = romheader.PCIRHeader;
+	if ( pcirheader )
+		undirom_parse_pcirheader ( undirom, pcirheader );
+
+	/* Add to UNDI ROM list and return */
+	DBGC ( undirom, "UNDIROM %p registered\n", undirom );
+	list_add ( &undirom->list, &undiroms );
+	return 0;
+
+ err:
+	free ( undirom );
+	return rc;
+}
+
+/**
+ * Create UNDI ROMs for all possible expansion ROMs
+ *
+ * @ret 
+ */
+static void undirom_probe_all_roms ( void ) {
+	static int probed = 0;
+	unsigned int rom_segment;
+
+	/* Perform probe only once */
+	if ( probed )
+		return;
+
+	DBG ( "Scanning for PXE expansion ROMs\n" );
+
+	/* Scan through expansion ROM region at 512 byte intervals */
+	for ( rom_segment = 0xc000 ; rom_segment < 0x10000 ;
+	      rom_segment += 0x20 ) {
+		undirom_probe ( rom_segment );
+	}
+
+	probed = 1;
+}
+
+/**
+ * Find UNDI ROM for PCI device
+ *
+ * @v vendor_id		PCI vendor ID
+ * @v device_id		PCI device ID
+ * @v rombase		ROM base address, or 0 for any
+ * @ret undirom		UNDI ROM, or NULL
+ */
+struct undi_rom * undirom_find_pci ( unsigned int vendor_id,
+				     unsigned int device_id,
+				     unsigned int rombase ) {
+	struct undi_rom *undirom;
+
+	undirom_probe_all_roms();
+
+	list_for_each_entry ( undirom, &undiroms, list ) {
+		if ( undirom->bus_type != PCI_NIC )
+			continue;
+		if ( undirom->bus_id.pci.vendor_id != vendor_id )
+			continue;
+		if ( undirom->bus_id.pci.device_id != device_id )
+			continue;
+		if ( rombase && ( ( undirom->rom_segment << 4 ) != rombase ) )
+			continue;
+		DBGC ( undirom, "UNDIROM %p matched PCI %04x:%04x (%08x)\n",
+		       undirom, vendor_id, device_id, rombase );
+		return undirom;
+	}
+
+	DBG ( "No UNDI ROM matched PCI %04x:%04x (%08x)\n",
+	      vendor_id, device_id, rombase );
+	return NULL;
+}