skel.c

linux下从网卡远程启动

/**************************************************************************
Etherboot -  BOOTP/TFTP Bootstrap Program
Skeleton NIC driver for Etherboot
***************************************************************************/

/*
 * 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, or (at
 * your option) any later version.
 */

/* to get some global routines like printf */
#include "etherboot.h"
/* to get the interface to the body of the program */
#include "nic.h"
/* to get the PCI support functions, if this is a PCI NIC */
#include "pci.h"
/* to get the ISA support functions, if this is an ISA NIC */
#include "isa.h"

/* NIC specific static variables go here */

/**************************************************************************
POLL - Wait for a frame
***************************************************************************/
static int skel_poll(struct nic *nic)
{
	/* return true if there's an ethernet packet ready to read */
	/* nic->packet should contain data on return */
	/* nic->packetlen should contain length of data */
	return (0);	/* initially as this is called to flush the input */
}

/**************************************************************************
TRANSMIT - Transmit a frame
***************************************************************************/
static void skel_transmit(
	struct nic *nic,
	const char *d,			/* Destination */
	unsigned int t,			/* Type */
	unsigned int s,			/* size */
	const char *p)			/* Packet */
{
	/* send the packet to destination */
}

/**************************************************************************
DISABLE - Turn off ethernet interface
***************************************************************************/
static void skel_disable(struct dev *dev)
{
	/* put the card in its initial state */
	/* This function serves 3 purposes.
	 * This disables DMA and interrupts so we don't receive
	 *  unexpected packets or interrupts from the card after
	 *  etherboot has finished. 
	 * This frees resources so etherboot may use
	 *  this driver on another interface
	 * This allows etherboot to reinitialize the interface
	 *  if something is something goes wrong.
	 */
}

/**************************************************************************
PROBE - Look for an adapter, this routine's visible to the outside
***************************************************************************/

#define board_found 1
#define valid_link 0
static int skel_probe(struct dev *dev, struct pci_device *pci)
{
	struct nic *nic = (struct nic *)dev;
	if (board_found && valid_link)
	{
		/* point to NIC specific routines */
		dev->disable  = skel_disable;
		nic->poll     = skel_poll;
		nic->transmit = skel_transmit;
		return 1;
	}
	/* else */
	return 0;
}

static struct pci_id skel_nics[] = {
PCI_ROM(0x0000, 0x0000, "skel-pci", "Skeleton PCI Adaptor"),
};

static struct pci_driver skel_driver __pci_driver = {
	.type     = NIC_DRIVER,
	.name     = "SKELETON/PCI",
	.probe    = skel_probe,
	.ids      = skel_nics,
	.id_count = sizeof(skel_nics)/sizeof(skel_nics[0]),
	.class    = 0,
};

/**************************************************************************
PROBE - Look for an adapter, this routine's visible to the outside
***************************************************************************/
static int skel_isa_probe(struct dev *dev, unsigned short *probe_addrs)
{
	struct nic *nic = (struct nic *)dev;
	/* if probe_addrs is 0, then routine can use a hardwired default */
	if (board_found && valid_link)
	{
		/* point to NIC specific routines */
		dev->disable  = skel_disable;
		nic->poll     = skel_poll;
		nic->transmit = skel_transmit;

		/* Report the ISA pnp id of the board */
		dev->devid.vendor_id = htons(GENERIC_ISAPNP_VENDOR);
		dev->devid.vendor_id = htons(0x1234);
		return 1;
	}
	/* else */
	return 0;
}

ISA_ROM("skel-isa", "Skeleton ISA driver")
static struct isa_driver skel_isa_driver __isa_driver = {
	.type    = NIC_DRIVER,
	.name    = "SKELETON/ISA",
	.probe   = skel_isa_probe,
	.ioaddrs = 0,
};