if_fe.c

很好的一个嵌入式linux平台下的bootloader

	{ NULL, NULL }
};

/*
 * Determine if the device is present
 *
 *   on entry:
 * 	a pointer to an isa_device struct
 *   on exit:
 *	zero if device not found
 *	or number of i/o addresses used (if found)
 */

int
fe_probe ( struct isa_device * isa_dev )
{
	struct fe_softc * sc, * u;
	int nports;
	struct fe_probe_list const * list;
	u_short const * addr;
	u_short single [ 2 ];

	/* Initialize "minimum" parts of our softc.  */
	sc = &fe_softc[ isa_dev->id_unit ];
	sc->sc_unit = isa_dev->id_unit;

#if FE_DEBUG >= 2
	log( LOG_INFO, "fe%d: %s\n", sc->sc_unit, fe_version );
#endif

#ifndef DEV_LKM
	/* Fill the device config data and register it.  */
	sc->kdc = fe_kdc_template;
	sc->kdc.kdc_unit = sc->sc_unit;
	sc->kdc.kdc_parentdata = isa_dev;
	dev_attach( &sc->kdc );
#endif

	/* Probe each possibility, one at a time.  */
	for ( list = fe_probe_list; list->probe != NULL; list++ ) {

		if ( isa_dev->id_iobase != NO_IOADDR ) {
			/* Probe one specific address.  */
			single[ 0 ] = isa_dev->id_iobase;
			single[ 1 ] = 0;
			addr = single;
		} else if ( list->addresses != NULL ) {
			/* Auto detect.  */
			addr = list->addresses;
		} else {
			/* We need a list of addresses to do auto detect.  */
			continue;
		}

		/* Probe all possible addresses for the board.  */
		while ( *addr != 0 ) {

			/* Don't probe already used address.  */
			for ( u = &fe_softc[0]; u < &fe_softc[NFE]; u++ ) {
				if ( u->addr == *addr ) break;
			}
			if ( u < &fe_softc[NFE] ) continue;

			/* Probe an address.  */
			sc->addr = *addr;
			nports = list->probe( isa_dev, sc );
			if ( nports > 0 ) {
				/* Found.  */
				isa_dev->id_iobase = *addr;
				return ( nports );
			}

			/* Try next.  */
			sc->addr = 0;
			addr++;
		}
	}

	/* Probe failed.  */
	return ( 0 );
}

/*
 * Check for specific bits in specific registers have specific values.
 */
struct fe_simple_probe_struct
{
	u_char port;	/* Offset from the base I/O address.  */
	u_char mask;	/* Bits to be checked.  */
	u_char bits;	/* Values to be compared against.  */
};

static INLINE int
fe_simple_probe ( u_short addr, struct fe_simple_probe_struct const * sp )
{
	struct fe_simple_probe_struct const * p;

	for ( p = sp; p->mask != 0; p++ ) {
		if ( ( INB( addr, p->port ) & p->mask ) != p->bits ) {
			return ( 0 );
		}
	}
	return ( 1 );
}

/*
 * Routines to read all bytes from the config EEPROM through MB86965A.
 * I'm not sure what exactly I'm doing here...  I was told just to follow
 * the steps, and it worked.  Could someone tell me why the following
 * code works?  (Or, why all similar codes I tried previously doesn't
 * work.)  FIXME.
 */

static INLINE void
strobe ( u_short bmpr16 )
{
	/*
	 * Output same value twice.  To speed-down execution?
	 */
	outb( bmpr16, FE_B16_SELECT );
	outb( bmpr16, FE_B16_SELECT );
	outb( bmpr16, FE_B16_SELECT | FE_B16_CLOCK );
	outb( bmpr16, FE_B16_SELECT | FE_B16_CLOCK );
	outb( bmpr16, FE_B16_SELECT );
	outb( bmpr16, FE_B16_SELECT );
}

static void
fe_read_eeprom ( struct fe_softc * sc, u_char * data )
{
	u_char n, val, bit;
	u_char save16, save17;

	/* Save old values of the registers.  */
	save16 = INB( sc->addr, FE_BMPR16 );
	save17 = INB( sc->addr, FE_BMPR17 );

	/* Read bytes from EEPROM; two bytes per an iterration.  */
	for ( n = 0; n < FE_EEPROM_SIZE / 2; n++ ) {

		/* Reset the EEPROM interface.  */
		OUTB( sc->addr, FE_BMPR16, 0x00 );
		OUTB( sc->addr, FE_BMPR17, 0x00 );
		OUTB( sc->addr, FE_BMPR16, FE_B16_SELECT );

		/* Start EEPROM access.  */
		OUTB( sc->addr, FE_BMPR17, FE_B17_DATA );
		STROBE( sc->addr, FE_BMPR16 );

		/* Pass the iterration count to the chip.  */
		val = 0x80 | n;
		for ( bit = 0x80; bit != 0x00; bit >>= 1 ) {
			OUTB( sv->addr, FE_BMPR17, ( val & bit ) ? FE_B17_DATA : 0 );
			STROBE( sc->addr, FE_BMPR16 );
		}
		OUTB( sc->addr, FE_BMPR17, 0x00 );

		/* Read a byte.  */
		val = 0;
		for ( bit = 0x80; bit != 0x00; bit >>= 1 ) {
			STROBE( sc->addr, FE_BMPR16 );
			if ( INB( sc->addr, FE_BMPR17 ) & FE_B17_DATA ) {
				val |= bit;
			}
		}
		*data++ = val;

		/* Read one more byte.  */
		val = 0;
		for ( bit = 0x80; bit != 0x00; bit >>= 1 ) {
			STROBE( sc->addr, FE_BMPR16 );
			if ( INB( sc->addr, FE_BMPR17 ) & FE_B17_DATA ) {
				val |= bit;
			}
		}
		*data++ = val;
	}

	/* Restore register values, in the case we had no 86965.  */
	OUTB( sc->addr, FE_BMPR16, save16 );
	OUTB( sc->addrm FE_BMPR17, save17 );

#if FE_DEBUG >= 3
	/* Report what we got.  */
	data -= FE_EEPROM_SIZE;
	log( LOG_INFO, "fe%d: EEPROM:"
		" %02x%02x%02x%02x %02x%02x%02x%02x -"
		" %02x%02x%02x%02x %02x%02x%02x%02x -"
		" %02x%02x%02x%02x %02x%02x%02x%02x -"
		" %02x%02x%02x%02x %02x%02x%02x%02x\n",
		sc->sc_unit,
		data[ 0], data[ 1], data[ 2], data[ 3],
		data[ 4], data[ 5], data[ 6], data[ 7],
		data[ 8], data[ 9], data[10], data[11],
		data[12], data[13], data[14], data[15],
		data[16], data[17], data[18], data[19],
		data[20], data[21], data[22], data[23],
		data[24], data[25], data[26], data[27],
		data[28], data[29], data[30], data[31] );
#endif
}

/*
 * Hardware (vendor) specific probe routines.
 */

/*
 * Probe and initialization for Fujitsu FMV-180 series boards
 */
static int
fe_probe_fmv ( struct isa_device *isa_dev, struct fe_softc * sc )
{
	int i, n;

	static u_short const ioaddr [ 8 ] =
		{ 0x220, 0x240, 0x260, 0x280, 0x2A0, 0x2C0, 0x300, 0x340 };
	static u_short const irqmap [ 4 ] =
		{ IRQ3,  IRQ7,  IRQ10, IRQ15 };

	static struct fe_simple_probe_struct const probe_table [] = {
		{ FE_DLCR2, 0x70, 0x00 },
		{ FE_DLCR4, 0x08, 0x00 },
	    /*	{ FE_DLCR5, 0x80, 0x00 },	Doesn't work.  */

		{ FE_FMV0, FE_FMV0_MAGIC_MASK,  FE_FMV0_MAGIC_VALUE },
		{ FE_FMV1, FE_FMV1_CARDID_MASK, FE_FMV1_CARDID_ID   },
		{ FE_FMV3, FE_FMV3_EXTRA_MASK,  FE_FMV3_EXTRA_VALUE },
#if 1
	/*
	 * Test *vendor* part of the station address for Fujitsu.
	 * The test will gain reliability of probe process, but
	 * it rejects FMV-180 clone boards manufactured by other vendors.
	 * We have to turn the test off when such cards are made available.
	 */
		{ FE_FMV4, 0xFF, 0x00 },
		{ FE_FMV5, 0xFF, 0x00 },
		{ FE_FMV6, 0xFF, 0x0E },
#else
	/*
	 * We can always verify the *first* 2 bits (in Ehternet
	 * bit order) are "no multicast" and "no local" even for
	 * unknown vendors.
	 */
		{ FE_FMV4, 0x03, 0x00 },
#endif
		{ 0 }
	};

#if 0
	/*
	 * Dont probe at all if the config says we are PCMCIA...
	 */
	if ( isa_dev->id_flags & FE_FLAGS_PCMCIA ) return ( 0 );
#endif

	/*
	 * See if the sepcified address is possible for FMV-180 series.
	 */
	for ( i = 0; i < 8; i++ ) {
		if ( ioaddr[ i ] == sc->addr ) break;
	}
	if ( i == 8 ) return 0;

	/* Simple probe.  */
	if ( !fe_simple_probe( sc->addr, probe_table ) ) return 0;

	/* Check if our I/O address matches config info on EEPROM.  */
	n = ( INB( sc->addr, FE_FMV2 ) & FE_FMV2_ADDR ) >> FE_FMV2_ADDR_SHIFT;
	if ( ioaddr[ n ] != sc->addr ) return 0;

	/* Determine the card type.  */
	switch ( INB( sc->addr, FE_FMV0 ) & FE_FMV0_MODEL ) {
	  case FE_FMV0_MODEL_FMV181:
		sc->type = FE_TYPE_FMV181;
		sc->typestr = "FMV-181";
		sc->sc_description = "Ethernet adapter: FMV-181";
		break;
	  case FE_FMV0_MODEL_FMV182:
		sc->type = FE_TYPE_FMV182;
		sc->typestr = "FMV-182";
		sc->sc_description = "Ethernet adapter: FMV-182";
		break;
	  default:
	  	/* Unknown card type: maybe a new model, but...  */
		return 0;
	}

	/*
	 * An FMV-180 has successfully been proved.
	 * Determine which IRQ to be used.
	 *
	 * In this version, we always get an IRQ assignment from the
	 * FMV-180's configuration EEPROM, ignoring that specified in
	 * config file.
	 */
	n = ( INB( sc->addr, FE_FMV2 ) & FE_FMV2_IRQ ) >> FE_FMV2_IRQ_SHIFT;
	isa_dev->id_irq = irqmap[ n ];

	/*
	 * Initialize constants in the per-line structure.
	 */

	/* Get our station address from EEPROM.  */
	inblk( sc->addr, FE_FMV4, sc->sc_enaddr, ETHER_ADDR_LEN );

	/* Make sure we got a valid station address.  */
	if ( ( sc->sc_enaddr[ 0 ] & 0x03 ) != 0x00
	  || ( sc->sc_enaddr[ 0 ] == 0x00
	    && sc->sc_enaddr[ 1 ] == 0x00
	    && sc->sc_enaddr[ 2 ] == 0x00 ) ) return 0;

	/* Register values which depend on board design.  */
	sc->proto_dlcr4 = FE_D4_LBC_DISABLE | FE_D4_CNTRL;
	sc->proto_dlcr5 = 0;
	sc->proto_dlcr7 = FE_D7_BYTSWP_LH | FE_D7_IDENT_EC;

	/*
	 * Program the 86960 as follows:
	 *	SRAM: 32KB, 100ns, byte-wide access.
	 *	Transmission buffer: 4KB x 2.
	 *	System bus interface: 16 bits.
	 * We cannot change these values but TXBSIZE, because they
	 * are hard-wired on the board.  Modifying TXBSIZE will affect
	 * the driver performance.
	 */
	sc->proto_dlcr6 = FE_D6_BUFSIZ_32KB | FE_D6_TXBSIZ_2x4KB
		| FE_D6_BBW_BYTE | FE_D6_SBW_WORD | FE_D6_SRAM_100ns;

	/*
	 * Minimum initialization of the hardware.
	 * We write into registers; hope I/O ports have no
	 * overlap with other boards.
	 */

	/* Initialize ASIC.  */
	OUTB( sc->addr, FE_FMV3, 0 );
	OUTB( sc->addr, FE_FMV10, 0 );

	/* Wait for a while.  I'm not sure this is necessary.  FIXME.  */
	DELAY(200);

	/* Initialize 86960.  */
	OUTB( sc->addr, FE_DLCR6, sc->proto_dlcr6 | FE_D6_DLC_DISABLE );
	DELAY(200);

	/* Disable all interrupts.  */
	OUTB( sc->addr, FE_DLCR2, 0 );
	OUTB( sc->addr, FE_DLCR3, 0 );

	/* Turn the "master interrupt control" flag of ASIC on.  */
	OUTB( sc->addr, FE_FMV3, FE_FMV3_ENABLE_FLAG );

	/*
	 * That's all.  FMV-180 occupies 32 I/O addresses, by the way.
	 */
	return 32;
}

/*
 * Probe and initialization for Allied-Telesis AT1700/RE2000 series.
 */
static int
fe_probe_ati ( struct isa_device * isa_dev, struct fe_softc * sc )
{
	int i, n;
	u_char eeprom [ FE_EEPROM_SIZE ];

	static u_short const ioaddr [ 8 ] =
		{ 0x260, 0x280, 0x2A0, 0x240, 0x340, 0x320, 0x380, 0x300 };
	static u_short const irqmap_lo [ 4 ] =
		{ IRQ3,  IRQ4,  IRQ5,  IRQ9 };
	static u_short const irqmap_hi [ 4 ] =
		{ IRQ10, IRQ11, IRQ12, IRQ15 };
	static struct fe_simple_probe_struct const probe_table [] = {
		{ FE_DLCR2,  0x70, 0x00 },
		{ FE_DLCR4,  0x08, 0x00 },
		{ FE_DLCR5,  0x80, 0x00 },
#if 0
		{ FE_BMPR16, 0x1B, 0x00 },
		{ FE_BMPR17, 0x7F, 0x00 },
#endif
		{ 0 }
	};

#if 0
	/*
	 * Don't probe at all if the config says we are PCMCIA...
	 */
	if ( isa_dev->id_flags & FE_FLAGS_PCMCIA ) return ( 0 );
#endif

#if FE_DEBUG >= 3
	log( LOG_INFO, "fe%d: probe (0x%x) for ATI\n", sc->sc_unit, sc->addr );
	fe_dump( LOG_INFO, sc, NULL );
#endif

	/*
	 * See if the sepcified address is possible for MB86965A JLI mode.
	 */
	for ( i = 0; i < 8; i++ ) {
		if ( ioaddr[ i ] == sc->addr ) break;
	}
	if ( i == 8 ) return 0;

	/*
	 * We should test if MB86965A is on the base address now.
	 * Unfortunately, it is very hard to probe it reliably, since
	 * we have no way to reset the chip under software control.
	 * On cold boot, we could check the "signature" bit patterns
	 * described in the Fujitsu document.  On warm boot, however,
	 * we can predict almost nothing about register values.
	 */
	if ( !fe_simple_probe( sc->addr, probe_table ) ) return 0;

	/* Check if our I/O address matches config info on 86965.  */
	n = ( INB( sc->addr, FE_BMPR19 ) & FE_B19_ADDR ) >> FE_B19_ADDR_SHIFT;
	if ( ioaddr[ n ] != sc->addr ) return 0;

	/*
	 * We are now almost sure we have an AT1700 at the given
	 * address.  So, read EEPROM through 86965.  We have to write
	 * into LSI registers to read from EEPROM.  I want to avoid it
	 * at this stage, but I cannot test the presense of the chip
	 * any further without reading EEPROM.  FIXME.
	 */
	fe_read_eeprom( sc, eeprom );

	/* Make sure that config info in EEPROM and 86965 agree.  */
	if ( eeprom[ FE_EEPROM_CONF ] != INB( sc->addr, FE_BMPR19 ) ) {
		return 0;
	}

	/*
	 * Determine the card type.
	 * There may be a way to identify various models.  FIXME.
	 */
	sc->type = FE_TYPE_AT1700;
	sc->typestr = "AT1700/RE2000";
	sc->sc_description = "Ethernet adapter: AT1700 or RE2000";

	/*
	 * I was told that RE2000 series has two variants on IRQ
	 * selection.  They are 3/4/5/9 and 10/11/12/15.  I don't know
	 * how we can distinguish which model is which.  For now, we
	 * just trust irq setting in config.  FIXME.
	 *
	 * I've heard that ATI puts an identification between these
	 * two models in the EEPROM.  Sounds reasonable.  I've also
	 * heard that Linux driver for AT1700 tests it.  O.K.  Let's
	 * try using it and see what happens.  Anyway, we will use an
	 * IRQ value passed by config (i.e., user), if one is
	 * available.  FIXME.
	 */
	n = ( INB( sc->addr, FE_BMPR19 ) & FE_B19_IRQ ) >> FE_B19_IRQ_SHIFT;
	if ( isa_dev->id_irq == 0 ) {
		/* Try to determine IRQ settings.  */
		if ( eeprom[ FE_EEP_ATI_TYPE ] & FE_EEP_ATI_TYPE_HIGHIRQ ) {
			isa_dev->id_irq = irqmap_hi[ n ];
		} else {
			isa_dev->id_irq = irqmap_lo[ n ];
		}
	}

	/*
	 * Initialize constants in the per-line structure.
	 */

	/* Get our station address from EEPROM.  */
	bcopy( eeprom + FE_EEP_ATI_ADDR, sc->sc_enaddr, ETHER_ADDR_LEN );

#if 1
	/*
	 * This test doesn't work well for AT1700 look-alike by
	 * other vendors.
	 */
	/* Make sure the vendor part is for Allied-Telesis.  */
	if ( sc->sc_enaddr[ 0 ] != 0x00
	  || sc->sc_enaddr[ 1 ] != 0x00
	  || sc->sc_enaddr[ 2 ] != 0xF4 ) return 0;

#else
	/* Make sure we got a valid station address.  */
	if ( ( sc->sc_enaddr[ 0 ] & 0x03 ) != 0x00
	  || ( sc->sc_enaddr[ 0 ] == 0x00
	    && sc->sc_enaddr[ 1 ] == 0x00
	    && sc->sc_enaddr[ 2 ] == 0x00 ) ) return 0;
#endif

	/* Should find all register prototypes here.  FIXME.  */
	sc->proto_dlcr4 = FE_D4_LBC_DISABLE | FE_D4_CNTRL;  /* FIXME */
	sc->proto_dlcr5 = 0;
	sc->proto_dlcr7 = FE_D7_BYTSWP_LH | FE_D7_IDENT_EC;