ne2000.c

uboot详细解读可用启动引导LINUX2.6内核

	DP_OUT(base, DP_RBCH, len >> 8);
	DP_OUT(base, DP_RSAL, 4);		/* Past header */
	DP_OUT(base, DP_RSAH, dp->rx_next);
	DP_OUT(base, DP_ISR, DP_ISR_RDC); /* Clear end of DMA */
	DP_OUT(base, DP_CR, DP_CR_RDMA | DP_CR_START);
#ifdef CYGHWR_NS_DP83902A_PLF_BROKEN_RX_DMA
	CYGACC_CALL_IF_DELAY_US(10);
#endif

	saved = false;
	for (i = 0; i < 1; i++) {
		if (data) {
			mlen = len;
#if DEBUG & 4
			printf(" sg buf %08lx len %08x \n", (u32) data, mlen);
			dx = 0;
#endif
			while (0 < mlen) {
				/* Saved byte from previous loop? */
				if (saved) {
					*data++ = saved_char;
					mlen--;
					saved = false;
					continue;
				}

				{
					u8 tmp;
					DP_IN_DATA(dp->data, tmp);
#if DEBUG & 4
					printf(" %02x", tmp);
					if (0 == (++dx % 16)) printf("\n ");
#endif
					*data++ = tmp;;
					mlen--;
				}
			}
#if DEBUG & 4
			printf("\n");
#endif
		}
	}
}

static void
dp83902a_TxEvent(void)
{
	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *) &nic;
	u8 *base = dp->base;
	u8 tsr;
	u32 key;

	DEBUG_FUNCTION();

	DP_IN(base, DP_TSR, tsr);
	if (dp->tx_int == 1) {
		key = dp->tx1_key;
		dp->tx1 = 0;
	} else {
		key = dp->tx2_key;
		dp->tx2 = 0;
	}
	/* Start next packet if one is ready */
	dp->tx_started = false;
	if (dp->tx1) {
		dp83902a_start_xmit(dp->tx1, dp->tx1_len);
		dp->tx_int = 1;
	} else if (dp->tx2) {
		dp83902a_start_xmit(dp->tx2, dp->tx2_len);
		dp->tx_int = 2;
	} else {
		dp->tx_int = 0;
	}
	/* Tell higher level we sent this packet */
	uboot_push_tx_done(key, 0);
}

/*
 * Read the tally counters to clear them. Called in response to a CNT
 * interrupt.
 */
static void
dp83902a_ClearCounters(void)
{
	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *) &nic;
	u8 *base = dp->base;
	u8 cnt1, cnt2, cnt3;

	DP_IN(base, DP_FER, cnt1);
	DP_IN(base, DP_CER, cnt2);
	DP_IN(base, DP_MISSED, cnt3);
	DP_OUT(base, DP_ISR, DP_ISR_CNT);
}

/*
 * Deal with an overflow condition. This code follows the procedure set
 * out in section 7.0 of the datasheet.
 */
static void
dp83902a_Overflow(void)
{
	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *)&nic;
	u8 *base = dp->base;
	u8 isr;

	/* Issue a stop command and wait 1.6ms for it to complete. */
	DP_OUT(base, DP_CR, DP_CR_STOP | DP_CR_NODMA);
	CYGACC_CALL_IF_DELAY_US(1600);

	/* Clear the remote byte counter registers. */
	DP_OUT(base, DP_RBCL, 0);
	DP_OUT(base, DP_RBCH, 0);

	/* Enter loopback mode while we clear the buffer. */
	DP_OUT(base, DP_TCR, DP_TCR_LOCAL);
	DP_OUT(base, DP_CR, DP_CR_START | DP_CR_NODMA);

	/*
	 * Read in as many packets as we can and acknowledge any and receive
	 * interrupts. Since the buffer has overflowed, a receive event of
	 * some kind will have occured.
	 */
	dp83902a_RxEvent();
	DP_OUT(base, DP_ISR, DP_ISR_RxP|DP_ISR_RxE);

	/* Clear the overflow condition and leave loopback mode. */
	DP_OUT(base, DP_ISR, DP_ISR_OFLW);
	DP_OUT(base, DP_TCR, DP_TCR_NORMAL);

	/*
	 * If a transmit command was issued, but no transmit event has occured,
	 * restart it here.
	 */
	DP_IN(base, DP_ISR, isr);
	if (dp->tx_started && !(isr & (DP_ISR_TxP|DP_ISR_TxE))) {
		DP_OUT(base, DP_CR, DP_CR_NODMA | DP_CR_TXPKT | DP_CR_START);
	}
}

static void
dp83902a_poll(void)
{
	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *) &nic;
	u8 *base = dp->base;
	u8 isr;

	DP_OUT(base, DP_CR, DP_CR_NODMA | DP_CR_PAGE0 | DP_CR_START);
	DP_IN(base, DP_ISR, isr);
	while (0 != isr) {
		/*
		 * The CNT interrupt triggers when the MSB of one of the error
		 * counters is set. We don't much care about these counters, but
		 * we should read their values to reset them.
		 */
		if (isr & DP_ISR_CNT) {
			dp83902a_ClearCounters();
		}
		/*
		 * Check for overflow. It's a special case, since there's a
		 * particular procedure that must be followed to get back into
		 * a running state.a
		 */
		if (isr & DP_ISR_OFLW) {
			dp83902a_Overflow();
		} else {
			/*
			 * Other kinds of interrupts can be acknowledged simply by
			 * clearing the relevant bits of the ISR. Do that now, then
			 * handle the interrupts we care about.
			 */
			DP_OUT(base, DP_ISR, isr);	/* Clear set bits */
			if (!dp->running) break;	/* Is this necessary? */
			/*
			 * Check for tx_started on TX event since these may happen
			 * spuriously it seems.
			 */
			if (isr & (DP_ISR_TxP|DP_ISR_TxE) && dp->tx_started) {
				dp83902a_TxEvent();
			}
			if (isr & (DP_ISR_RxP|DP_ISR_RxE)) {
				dp83902a_RxEvent();
			}
		}
		DP_IN(base, DP_ISR, isr);
	}
}

/* find prom (taken from pc_net_cs.c from Linux) */

#include "8390.h"
/*
typedef struct hw_info_t {
	u_int	offset;
	u_char	a0, a1, a2;
	u_int	flags;
} hw_info_t;
*/
#define DELAY_OUTPUT	0x01
#define HAS_MISC_REG	0x02
#define USE_BIG_BUF	0x04
#define HAS_IBM_MISC	0x08
#define IS_DL10019	0x10
#define IS_DL10022	0x20
#define HAS_MII		0x40
#define USE_SHMEM	0x80	/* autodetected */

#define AM79C9XX_HOME_PHY	0x00006B90	/* HomePNA PHY */
#define AM79C9XX_ETH_PHY	0x00006B70	/* 10baseT PHY */
#define MII_PHYID_REV_MASK	0xfffffff0
#define MII_PHYID_REG1		0x02
#define MII_PHYID_REG2		0x03

static hw_info_t hw_info[] = {
	{ /* Accton EN2212 */ 0x0ff0, 0x00, 0x00, 0xe8, DELAY_OUTPUT },
	{ /* Allied Telesis LA-PCM */ 0x0ff0, 0x00, 0x00, 0xf4, 0 },
	{ /* APEX MultiCard */ 0x03f4, 0x00, 0x20, 0xe5, 0 },
	{ /* ASANTE FriendlyNet */ 0x4910, 0x00, 0x00, 0x94,
			DELAY_OUTPUT | HAS_IBM_MISC },
	{ /* Danpex EN-6200P2 */ 0x0110, 0x00, 0x40, 0xc7, 0 },
	{ /* DataTrek NetCard */ 0x0ff0, 0x00, 0x20, 0xe8, 0 },
	{ /* Dayna CommuniCard E */ 0x0110, 0x00, 0x80, 0x19, 0 },
	{ /* D-Link DE-650 */ 0x0040, 0x00, 0x80, 0xc8, 0 },
	{ /* EP-210 Ethernet */ 0x0110, 0x00, 0x40, 0x33, 0 },
	{ /* EP4000 Ethernet */ 0x01c0, 0x00, 0x00, 0xb4, 0 },
	{ /* Epson EEN10B */ 0x0ff0, 0x00, 0x00, 0x48,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* ELECOM Laneed LD-CDWA */ 0xb8, 0x08, 0x00, 0x42, 0 },
	{ /* Hypertec Ethernet */ 0x01c0, 0x00, 0x40, 0x4c, 0 },
	{ /* IBM CCAE */ 0x0ff0, 0x08, 0x00, 0x5a,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* IBM CCAE */ 0x0ff0, 0x00, 0x04, 0xac,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* IBM CCAE */ 0x0ff0, 0x00, 0x06, 0x29,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* IBM FME */ 0x0374, 0x08, 0x00, 0x5a,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* IBM FME */ 0x0374, 0x00, 0x04, 0xac,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* Kansai KLA-PCM/T */ 0x0ff0, 0x00, 0x60, 0x87,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* NSC DP83903 */ 0x0374, 0x08, 0x00, 0x17,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* NSC DP83903 */ 0x0374, 0x00, 0xc0, 0xa8,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* NSC DP83903 */ 0x0374, 0x00, 0xa0, 0xb0,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* NSC DP83903 */ 0x0198, 0x00, 0x20, 0xe0,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* I-O DATA PCLA/T */ 0x0ff0, 0x00, 0xa0, 0xb0, 0 },
	{ /* Katron PE-520 */ 0x0110, 0x00, 0x40, 0xf6, 0 },
	{ /* Kingston KNE-PCM/x */ 0x0ff0, 0x00, 0xc0, 0xf0,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* Kingston KNE-PCM/x */ 0x0ff0, 0xe2, 0x0c, 0x0f,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* Kingston KNE-PC2 */ 0x0180, 0x00, 0xc0, 0xf0, 0 },
	{ /* Maxtech PCN2000 */ 0x5000, 0x00, 0x00, 0xe8, 0 },
	{ /* NDC Instant-Link */ 0x003a, 0x00, 0x80, 0xc6, 0 },
	{ /* NE2000 Compatible */ 0x0ff0, 0x00, 0xa0, 0x0c, 0 },
	{ /* Network General Sniffer */ 0x0ff0, 0x00, 0x00, 0x65,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* Panasonic VEL211 */ 0x0ff0, 0x00, 0x80, 0x45,
			HAS_MISC_REG | HAS_IBM_MISC },
	{ /* PreMax PE-200 */ 0x07f0, 0x00, 0x20, 0xe0, 0 },
	{ /* RPTI EP400 */ 0x0110, 0x00, 0x40, 0x95, 0 },
	{ /* SCM Ethernet */ 0x0ff0, 0x00, 0x20, 0xcb, 0 },
	{ /* Socket EA */ 0x4000, 0x00, 0xc0, 0x1b,
			DELAY_OUTPUT | HAS_MISC_REG | USE_BIG_BUF },
	{ /* Socket LP-E CF+ */ 0x01c0, 0x00, 0xc0, 0x1b, 0 },
	{ /* SuperSocket RE450T */ 0x0110, 0x00, 0xe0, 0x98, 0 },
	{ /* Volktek NPL-402CT */ 0x0060, 0x00, 0x40, 0x05, 0 },
	{ /* NEC PC-9801N-J12 */ 0x0ff0, 0x00, 0x00, 0x4c, 0 },
	{ /* PCMCIA Technology OEM */ 0x01c8, 0x00, 0xa0, 0x0c, 0 },
	{ /* Qemu */ 0x0, 0x52, 0x54, 0x00, 0 }
};

#define NR_INFO		(sizeof(hw_info)/sizeof(hw_info_t))

#define PCNET_CMD	0x00
#define PCNET_DATAPORT	0x10	/* NatSemi-defined port window offset. */
#define PCNET_RESET	0x1f	/* Issue a read to reset, a write to clear. */
#define PCNET_MISC	0x18	/* For IBM CCAE and Socket EA cards */

static void pcnet_reset_8390(void)
{
	int i, r;

	PRINTK("nic base is %lx\n", nic.base);

	n2k_outb(E8390_NODMA + E8390_PAGE0+E8390_STOP, E8390_CMD);
	PRINTK("cmd (at %lx) is %x\n", nic.base + E8390_CMD, n2k_inb(E8390_CMD));
	n2k_outb(E8390_NODMA+E8390_PAGE1+E8390_STOP, E8390_CMD);
	PRINTK("cmd (at %lx) is %x\n", nic.base + E8390_CMD, n2k_inb(E8390_CMD));
	n2k_outb(E8390_NODMA+E8390_PAGE0+E8390_STOP, E8390_CMD);
	PRINTK("cmd (at %lx) is %x\n", nic.base + E8390_CMD, n2k_inb(E8390_CMD));
	n2k_outb(E8390_NODMA+E8390_PAGE0+E8390_STOP, E8390_CMD);

	n2k_outb(n2k_inb(PCNET_RESET), PCNET_RESET);

	for (i = 0; i < 100; i++) {
		if ((r = (n2k_inb(EN0_ISR) & ENISR_RESET)) != 0)
			break;
		PRINTK("got %x in reset\n", r);
		udelay(100);
	}
	n2k_outb(ENISR_RESET, EN0_ISR); /* Ack intr. */

	if (i == 100)
		printf("pcnet_reset_8390() did not complete.\n");
} /* pcnet_reset_8390 */

int get_prom(u8* mac_addr) __attribute__ ((weak, alias ("__get_prom")));
int __get_prom(u8* mac_addr)
{
	u8 prom[32];
	int i, j;
	struct {
		u_char value, offset;
	} program_seq[] = {
		{E8390_NODMA+E8390_PAGE0+E8390_STOP, E8390_CMD}, /* Select page 0*/
		{0x48, EN0_DCFG},		/* Set byte-wide (0x48) access. */
		{0x00, EN0_RCNTLO},		/* Clear the count regs. */
		{0x00, EN0_RCNTHI},
		{0x00, EN0_IMR},		/* Mask completion irq. */
		{0xFF, EN0_ISR},
		{E8390_RXOFF, EN0_RXCR},	/* 0x20 Set to monitor */
		{E8390_TXOFF, EN0_TXCR},	/* 0x02 and loopback mode. */
		{32, EN0_RCNTLO},
		{0x00, EN0_RCNTHI},
		{0x00, EN0_RSARLO},		/* DMA starting at 0x0000. */
		{0x00, EN0_RSARHI},
		{E8390_RREAD+E8390_START, E8390_CMD},
	};

	PRINTK ("trying to get MAC via prom reading\n");

	pcnet_reset_8390 ();

	mdelay (10);

	for (i = 0; i < sizeof (program_seq) / sizeof (program_seq[0]); i++)
		n2k_outb (program_seq[i].value, program_seq[i].offset);

	PRINTK ("PROM:");
	for (i = 0; i < 32; i++) {
		prom[i] = n2k_inb (PCNET_DATAPORT);
		PRINTK (" %02x", prom[i]);
	}
	PRINTK ("\n");
	for (i = 0; i < NR_INFO; i++) {
		if ((prom[0] == hw_info[i].a0) &&
			(prom[2] == hw_info[i].a1) &&
			(prom[4] == hw_info[i].a2)) {
			PRINTK ("matched board %d\n", i);
			break;
		}
	}
	if ((i < NR_INFO) || ((prom[28] == 0x57) && (prom[30] == 0x57))) {
		PRINTK ("on exit i is %d/%ld\n", i, NR_INFO);
		PRINTK ("MAC address is ");
		for (j = 0; j < 6; j++) {
			mac_addr[j] = prom[j << 1];
			PRINTK ("%02x:", mac_addr[i]);
		}
		PRINTK ("\n");
		return (i < NR_INFO) ? i : 0;
	}
	return 0;
}

/* U-boot specific routines */
static u8 *pbuf = NULL;

static int pkey = -1;
static int initialized = 0;

void uboot_push_packet_len(int len) {
	PRINTK("pushed len = %d\n", len);
	if (len >= 2000) {
		printf("NE2000: packet too big\n");
		return;
	}
	dp83902a_recv(&pbuf[0], len);

	/*Just pass it to the upper layer*/
	NetReceive(&pbuf[0], len);
}

void uboot_push_tx_done(int key, int val) {
	PRINTK("pushed key = %d\n", key);
	pkey = key;
}

int eth_init(bd_t *bd) {
	int r;
	u8 dev_addr[6];
	char ethaddr[20];

	PRINTK("### eth_init\n");

	if (!pbuf) {
		pbuf = malloc(2000);
		if (!pbuf) {
			printf("Cannot allocate rx buffer\n");
			return -1;
		}
	}

#ifdef CONFIG_DRIVER_NE2000_CCR
	{
		vu_char *p = (vu_char *) CONFIG_DRIVER_NE2000_CCR;

		PRINTK("CCR before is %x\n", *p);
		*p = CONFIG_DRIVER_NE2000_VAL;
		PRINTK("CCR after is %x\n", *p);
	}
#endif

	nic.base = (u8 *) CONFIG_DRIVER_NE2000_BASE;

	r = get_prom(dev_addr);
	if (!r)
		return -1;

	sprintf (ethaddr, "%02X:%02X:%02X:%02X:%02X:%02X",
		 dev_addr[0], dev_addr[1],
		 dev_addr[2], dev_addr[3],
		 dev_addr[4], dev_addr[5]) ;
	PRINTK("Set environment from HW MAC addr = \"%s\"\n", ethaddr);
	setenv ("ethaddr", ethaddr);

	nic.data = nic.base + DP_DATA;
	nic.tx_buf1 = START_PG;
	nic.tx_buf2 = START_PG2;
	nic.rx_buf_start = RX_START;
	nic.rx_buf_end = RX_END;

	if (dp83902a_init() == false)
		return -1;

	dp83902a_start(dev_addr);
	initialized = 1;

	return 0;
}

void eth_halt() {

	PRINTK("### eth_halt\n");
	if(initialized)
		dp83902a_stop();
	initialized = 0;
}

int eth_rx() {
	dp83902a_poll();
	return 1;
}

int eth_send(volatile void *packet, int length) {
	int tmo;

	PRINTK("### eth_send\n");

	pkey = -1;

	dp83902a_send((u8 *) packet, length, 666);
	tmo = get_timer (0) + TOUT * CFG_HZ;
	while(1) {
		dp83902a_poll();
		if (pkey != -1) {
			PRINTK("Packet sucesfully sent\n");
			return 0;
		}
		if (get_timer (0) >= tmo) {
			printf("transmission error (timoeut)\n");
			return 0;
		}

	}
	return 0;
}