ne2000_base.c

来自「最新版的u-boot,2008-10-18发布」· C语言 代码 · 共 758 行 · 第 1/2 页

		DP_IN(base, DP_P1_CURP, cur);
		DP_OUT(base, DP_P1_CR, DP_CR_PAGE0 | DP_CR_NODMA | DP_CR_START);
		DP_IN(base, DP_BNDRY, pkt);

		pkt += 1;
		if (pkt == dp->rx_buf_end)
			pkt = dp->rx_buf_start;

		if (pkt == cur) {
			break;
		}
		DP_OUT(base, DP_RBCL, sizeof(rcv_hdr));
		DP_OUT(base, DP_RBCH, 0);
		DP_OUT(base, DP_RSAL, 0);
		DP_OUT(base, DP_RSAH, pkt);
		if (dp->rx_next == pkt) {
			if (cur == dp->rx_buf_start)
				DP_OUT(base, DP_BNDRY, dp->rx_buf_end - 1);
			else
				DP_OUT(base, DP_BNDRY, cur - 1); /* Update pointer */
			return;
		}
		dp->rx_next = pkt;
		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

		/* read header (get data size)*/
		for (i = 0; i < sizeof(rcv_hdr);) {
			DP_IN_DATA(dp->data, rcv_hdr[i++]);
		}

#if DEBUG & 5
		printf("rx hdr %02x %02x %02x %02x\n",
			rcv_hdr[0], rcv_hdr[1], rcv_hdr[2], rcv_hdr[3]);
#endif
		len = ((rcv_hdr[3] << 8) | rcv_hdr[2]) - sizeof(rcv_hdr);

		/* data read */
		uboot_push_packet_len(len);

		if (rcv_hdr[1] == dp->rx_buf_start)
			DP_OUT(base, DP_BNDRY, dp->rx_buf_end - 1);
		else
			DP_OUT(base, DP_BNDRY, rcv_hdr[1] - 1); /* Update pointer */
	}
}

/*
 * This function is called as a result of the "eth_drv_recv()" call above.
 * It's job is to actually fetch data for a packet from the hardware once
 * memory buffers have been allocated for the packet. Note that the buffers
 * may come in pieces, using a scatter-gather list. This allows for more
 * efficient processing in the upper layers of the stack.
 */
static void
dp83902a_recv(u8 *data, int len)
{
	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *) &nic;
	u8 *base = dp->base;
	int i, mlen;
	u8 saved_char = 0;
	bool saved;
#if DEBUG & 4
	int dx;
#endif

	DEBUG_FUNCTION();

#if DEBUG & 5
	printf("Rx packet %d length %d\n", dp->rx_next, len);
#endif

	/* Read incoming packet data */
	DP_OUT(base, DP_CR, DP_CR_PAGE0 | DP_CR_NODMA | DP_CR_START);
	DP_OUT(base, DP_RBCL, len & 0xFF);
	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);
	}
}


/* 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, nic.base);
	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;
}