patch-2.4.2 linux/arch/cris/drivers/ethernet.c

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diff -u --recursive --new-file v2.4.1/linux/arch/cris/drivers/ethernet.c linux/arch/cris/drivers/ethernet.c
@@ -0,0 +1,1041 @@
+/* $Id: ethernet.c,v 1.5 2000/11/29 17:22:22 bjornw Exp $
+ *
+ * e100net.c: A network driver for the ETRAX 100LX network controller.
+ *
+ * Copyright (c) 1998-2000 Axis Communications AB.
+ *
+ * The outline of this driver comes from skeleton.c.
+ *
+ * $Log: ethernet.c,v $
+ * Revision 1.5  2000/11/29 17:22:22  bjornw
+ * Get rid of the udword types legacy stuff
+ *
+ * Revision 1.4  2000/11/22 16:36:09  bjornw
+ * Please marketing by using the correct case when spelling Etrax.
+ *
+ * Revision 1.3  2000/11/21 16:43:04  bjornw
+ * Minor short->int change
+ *
+ * Revision 1.2  2000/11/08 14:27:57  bjornw
+ * 2.4 port
+ *
+ * Revision 1.1  2000/11/06 13:56:00  bjornw
+ * Verbatim copy of the 1.24 version of e100net.c from elinux
+ *
+ * Revision 1.24  2000/10/04 15:55:23  bjornw
+ * * Use virt_to_phys etc. for DMA addresses
+ * * Removed bogus CHECKSUM_UNNECESSARY
+ *
+ *
+ */
+
+#include <linux/module.h>
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/interrupt.h>
+#include <linux/ptrace.h>
+#include <linux/ioport.h>
+#include <linux/in.h>
+#include <linux/malloc.h>
+#include <linux/string.h>
+#include <asm/system.h>
+#include <asm/bitops.h>
+#include <linux/spinlock.h>
+#include <asm/io.h>
+#include <asm/dma.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+
+#include <asm/svinto.h>
+
+//#define ETHDEBUG
+
+#define D(x)
+
+/*
+ * The name of the card. Is used for messages and in the requests for
+ * io regions, irqs and dma channels
+ */
+
+static const char* cardname = "ETRAX 100LX built-in ethernet controller";
+
+/* A default ethernet address. Highlevel SW will set the real one later */
+
+static struct sockaddr default_mac = {
+	0,
+        { 0x00, 0x40, 0x8C, 0xCD, 0x00, 0x00 }
+};
+
+/* Information that need to be kept for each board. */
+struct net_local {
+	struct net_device_stats stats;
+
+	/* Tx control lock.  This protects the transmit buffer ring
+	 * state along with the "tx full" state of the driver.  This
+	 * means all netif_queue flow control actions are protected
+	 * by this lock as well.
+	 */
+	spinlock_t lock;
+};
+
+#define NETWORK_DMARX_IRQ 17  /* irq 17 is the DMA1 irq */
+#define NETWORK_DMATX_IRQ 16  /* irq 16 is the DMA0 irq */
+#define NETWORK_STATUS_IRQ 6  /* irq 6 is the network irq */
+
+/* Dma descriptors etc. */
+
+#define RX_BUF_SIZE 32768
+
+#define MAX_MEDIA_DATA_SIZE 1518
+
+#define MIN_PACKET_LEN      46
+#define ETHER_HEAD_LEN      14
+
+/* 
+** MDIO constants.
+*/
+#define MDIO_BASE_STATUS_REG   0x1
+#define MDIO_BASE_CONTROL_REG  0x0
+#define MDIO_LINK_UP_MASK      0x4
+#define MDIO_START                          0x1
+#define MDIO_READ                           0x2
+#define MDIO_WRITE                          0x1
+#define MDIO_PREAMBLE              0xfffffffful
+
+/* Broadcom specific */
+#define MDIO_AUX_CTRL_STATUS_REG           0x18
+#define MDIO_SPEED                          0x2
+#define MDIO_PHYS_ADDR                      0x0
+
+/* Network flash constants */
+#define NET_FLASH_TIME                        2 /* 20 ms */
+#define NET_LINK_UP_CHECK_INTERVAL          200 /* 2 s   */
+
+/* RX_DESC_BUF_SIZE should be a multiple of four to avoid the buffer
+ * alignment bug in Etrax 100 release 1
+ */
+
+#define RX_DESC_BUF_SIZE   256
+#define NBR_OF_RX_DESC     (RX_BUF_SIZE / \
+			    RX_DESC_BUF_SIZE)
+
+#define GET_BIT(bit,val)   (((val) >> (bit)) & 0x01)
+
+static etrax_dma_descr *myNextRxDesc;  /* Points to the next descriptor to
+					  to be processed */
+static etrax_dma_descr *myLastRxDesc;  /* The last processed descriptor */
+static etrax_dma_descr *myPrevRxDesc;  /* The descriptor right before myNextRxDesc */
+
+static unsigned char RxBuf[RX_BUF_SIZE];
+
+static etrax_dma_descr RxDescList[NBR_OF_RX_DESC];
+static etrax_dma_descr TxDesc;
+
+static struct sk_buff *tx_skb;
+
+/* Network speed indication. */
+static struct timer_list speed_timer;
+static struct timer_list clear_led_timer;
+static int current_speed;
+static int led_clear_time;
+static int nolink;
+
+/* Index to functions, as function prototypes. */
+
+static int etrax_ethernet_init(struct net_device *dev);
+
+static int e100_open(struct net_device *dev);
+static int e100_set_mac_address(struct net_device *dev, void *addr);
+static int e100_send_packet(struct sk_buff *skb, struct net_device *dev);
+static void e100rx_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+static void e100tx_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+static void e100nw_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+static void e100_rx(struct net_device *dev);
+static int e100_close(struct net_device *dev);
+static struct net_device_stats *e100_get_stats(struct net_device *dev);
+static void set_multicast_list(struct net_device *dev);
+static void e100_hardware_send_packet(char *buf, int length);
+static void update_rx_stats(struct net_device_stats *);
+static void update_tx_stats(struct net_device_stats *);
+
+static void e100_check_speed(unsigned long dummy);
+static unsigned short e100_get_mdio_reg(unsigned char reg_num);
+static void e100_send_mdio_cmd(unsigned short cmd, int write_cmd);
+static void e100_send_mdio_bit(unsigned char bit);
+static unsigned char e100_receive_mdio_bit(void);
+static void e100_reset_tranceiver(void);
+
+static void e100_clear_network_leds(unsigned long dummy);
+
+#define tx_done(dev) (*R_DMA_CH0_CMD == 0)
+
+/*
+ * Check for a network adaptor of this type, and return '0' if one exists.
+ * If dev->base_addr == 0, probe all likely locations.
+ * If dev->base_addr == 1, always return failure.
+ * If dev->base_addr == 2, allocate space for the device and return success
+ * (detachable devices only).
+ */
+
+static int __init
+etrax_ethernet_init(struct net_device *dev)
+{
+	int i;
+	int anOffset = 0;
+
+	printk("ETRAX 100LX 10/100MBit ethernet v2.0 (c) 2000 Axis Communications AB\n");
+
+	dev->base_addr = (unsigned int)R_NETWORK_SA_0; /* just to have something to show */
+
+	printk("%s initialized\n", dev->name);
+
+	/* make Linux aware of the new hardware  */
+
+	if (!dev) {
+		printk("dev == NULL. Should this happen?\n");
+		dev = init_etherdev(dev, sizeof(struct net_local));
+	}
+
+	/* setup generic handlers and stuff in the dev struct */
+
+	ether_setup(dev);
+
+	/* make room for the local structure containing stats etc */
+
+	dev->priv = kmalloc(sizeof(struct net_local), GFP_KERNEL);
+	if (dev->priv == NULL)
+		return -ENOMEM;
+	memset(dev->priv, 0, sizeof(struct net_local));
+
+	/* now setup our etrax specific stuff */
+
+	dev->irq = NETWORK_DMARX_IRQ; /* we really use DMATX as well... */
+	dev->dma = 1;
+
+	/* fill in our handlers so the network layer can talk to us in the future */
+
+	dev->open               = e100_open;
+	dev->hard_start_xmit    = e100_send_packet;
+	dev->stop               = e100_close;
+	dev->get_stats          = e100_get_stats;
+	dev->set_multicast_list = set_multicast_list;
+	dev->set_mac_address    = e100_set_mac_address;
+
+	/* set the default MAC address */
+
+	e100_set_mac_address(dev, &default_mac);
+
+	/* Initialise the list of Etrax DMA-descriptors */
+
+	/* Initialise receive descriptors */
+
+	for(i = 0; i < (NBR_OF_RX_DESC - 1); i++) {
+		RxDescList[i].ctrl   = 0;
+		RxDescList[i].sw_len = RX_DESC_BUF_SIZE;
+		RxDescList[i].next   = virt_to_phys(&RxDescList[i + 1]);
+		RxDescList[i].buf    = virt_to_phys(RxBuf + anOffset);
+		RxDescList[i].status = 0;
+		RxDescList[i].hw_len = 0;
+		anOffset += RX_DESC_BUF_SIZE;
+	}
+
+	RxDescList[i].ctrl   = d_eol;
+	RxDescList[i].sw_len = RX_DESC_BUF_SIZE;
+	RxDescList[i].next   = virt_to_phys(&RxDescList[0]);
+	RxDescList[i].buf    = virt_to_phys(RxBuf + anOffset);
+	RxDescList[i].status = 0;
+	RxDescList[i].hw_len = 0;
+
+	/* Initialise initial pointers */
+
+	myNextRxDesc = &RxDescList[0];
+	myLastRxDesc = &RxDescList[NBR_OF_RX_DESC - 1];
+	myPrevRxDesc = &RxDescList[NBR_OF_RX_DESC - 1];
+
+	/* Initialize speed indicator stuff. */
+
+	nolink = 0;
+	current_speed = 10;
+	speed_timer.expires = jiffies + NET_LINK_UP_CHECK_INTERVAL;
+	speed_timer.function = e100_check_speed;
+	add_timer(&speed_timer);
+	clear_led_timer.function = e100_clear_network_leds;
+	clear_led_timer.expires = jiffies + 10;
+	add_timer(&clear_led_timer);
+
+	return 0;
+}
+
+/* set MAC address of the interface. called from the core after a
+ * SIOCSIFADDR ioctl, and from the bootup above.
+ */
+
+static int
+e100_set_mac_address(struct net_device *dev, void *p)
+{
+	struct sockaddr *addr = p;
+	int i;
+
+	/* remember it */
+
+        memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
+
+	/* Write it to the hardware.
+	 * Note the way the address is wrapped:
+	 * *R_NETWORK_SA_0 = a0_0 | (a0_1 << 8) | (a0_2 << 16) | (a0_3 << 24);
+	 * *R_NETWORK_SA_1 = a0_4 | (a0_5 << 8);
+	 */
+	
+	*R_NETWORK_SA_0 = dev->dev_addr[0] | (dev->dev_addr[1] << 8) |
+		(dev->dev_addr[2] << 16) | (dev->dev_addr[3] << 24);
+	*R_NETWORK_SA_1 = dev->dev_addr[4] | (dev->dev_addr[5] << 8);
+	*R_NETWORK_SA_2 = 0;
+
+	/* show it in the log as well */
+
+	printk("%s: changed MAC to ", dev->name);
+
+	for (i = 0; i < 5; i++)
+		printk("%02X:", dev->dev_addr[i]);
+
+	printk("%02X\n", dev->dev_addr[i]);
+
+	return 0;
+}
+
+/*
+ * Open/initialize the board. This is called (in the current kernel)
+ * sometime after booting when the 'ifconfig' program is run.
+ *
+ * This routine should set everything up anew at each open, even
+ * registers that "should" only need to be set once at boot, so that
+ * there is non-reboot way to recover if something goes wrong.
+ */
+
+static int
+e100_open(struct net_device *dev)
+{
+	unsigned long flags;
+
+	/* disable the ethernet interface while we configure it */
+
+	*R_NETWORK_GEN_CONFIG =
+		IO_STATE(R_NETWORK_GEN_CONFIG, phy,    mii_clk) |
+		IO_STATE(R_NETWORK_GEN_CONFIG, enable, off);
+
+	/* enable the MDIO output pin */
+
+	*R_NETWORK_MGM_CTRL = IO_STATE(R_NETWORK_MGM_CTRL, mdoe, enable);
+
+	*R_IRQ_MASK0_CLR = 0xe0000; /* clear excessive_col, over/underrun irq mask */
+	*R_IRQ_MASK2_CLR = 0xf; /* clear dma0 and 1 eop and descr irq masks */
+
+	/* Reset and wait for the DMA channels */
+
+	RESET_DMA(0);
+	RESET_DMA(1);
+	WAIT_DMA(0);
+	WAIT_DMA(1);
+
+	/* Initialise the etrax network controller */
+
+	/* allocate the irq corresponding to the receiving DMA */
+
+	if (request_irq(NETWORK_DMARX_IRQ, e100rx_interrupt, 0,
+			cardname, (void *)dev)) {
+		goto grace_exit;
+	}
+
+	/* allocate the irq corresponding to the transmitting DMA */
+
+	if (request_irq(NETWORK_DMATX_IRQ, e100tx_interrupt, 0,
+			cardname, (void *)dev)) {
+		goto grace_exit;
+	}
+
+	/* allocate the irq corresponding to the network errors etc */
+
+	if (request_irq(NETWORK_STATUS_IRQ, e100nw_interrupt, 0,
+			cardname, (void *)dev)) {
+		goto grace_exit;
+	}
+
+	/*
+	 * Always allocate the DMA channels after the IRQ,
+	 * and clean up on failure.
+	 */
+
+	if(request_dma(0, cardname)) {
+		goto grace_exit;
+	}
+
+	if(request_dma(1, cardname)) {
+	grace_exit:
+		/* this will cause some 'trying to free free irq' but what the heck... */
+		free_dma(0);
+		free_irq(NETWORK_DMARX_IRQ, NULL);
+		free_irq(NETWORK_DMATX_IRQ, NULL);
+		free_irq(NETWORK_STATUS_IRQ, NULL);
+		return -EAGAIN;
+	}
+
+	/* give the HW an idea of what MAC address we want */
+
+	*R_NETWORK_SA_0 = dev->dev_addr[0] | (dev->dev_addr[1] << 8) |
+		(dev->dev_addr[2] << 16) | (dev->dev_addr[3] << 24);
+	*R_NETWORK_SA_1 = dev->dev_addr[4] | (dev->dev_addr[5] << 8);
+	*R_NETWORK_SA_2 = 0;
+
+#if 0
+	/* use promiscuous mode for testing */
+	*R_NETWORK_GA_0 = 0xffffffff;
+	*R_NETWORK_GA_1 = 0xffffffff;
+
+	*R_NETWORK_REC_CONFIG = 0xd; /* broadcast rec, individ. rec, ma0 enabled */
+#else
+	*R_NETWORK_REC_CONFIG =
+		IO_STATE(R_NETWORK_REC_CONFIG, broadcast, receive) |
+		IO_STATE(R_NETWORK_REC_CONFIG, ma0,       enable);
+#endif
+
+	*R_NETWORK_GEN_CONFIG =
+		IO_STATE(R_NETWORK_GEN_CONFIG, phy,    mii_clk) |
+		IO_STATE(R_NETWORK_GEN_CONFIG, enable, on);
+
+	save_flags(flags);
+	cli();
+
+	/* enable the irq's for ethernet DMA */
+
+	*R_IRQ_MASK2_SET =
+		IO_STATE(R_IRQ_MASK2_SET, dma0_eop, set) |
+		IO_STATE(R_IRQ_MASK2_SET, dma1_eop, set);
+
+	*R_IRQ_MASK0_SET =
+		IO_STATE(R_IRQ_MASK0_SET, overrun,       set) |
+		IO_STATE(R_IRQ_MASK0_SET, underrun,      set) |
+		IO_STATE(R_IRQ_MASK0_SET, excessive_col, set);
+
+	tx_skb = 0;
+
+	/* make sure the irqs are cleared */
+
+	*R_DMA_CH0_CLR_INTR = IO_STATE(R_DMA_CH0_CLR_INTR, clr_eop, do);
+	*R_DMA_CH1_CLR_INTR = IO_STATE(R_DMA_CH1_CLR_INTR, clr_eop, do);
+
+	/* make sure the rec and transmit error counters are cleared */
+
+	(void)*R_REC_COUNTERS;  /* dummy read */
+	(void)*R_TR_COUNTERS;   /* dummy read */
+
+	/* start the receiving DMA channel so we can receive packets from now on */
+
+	*R_DMA_CH1_FIRST = virt_to_phys(myNextRxDesc);
+	*R_DMA_CH1_CMD = IO_STATE(R_DMA_CH1_CMD, cmd, start);
+
+	restore_flags(flags);
+	
+	/* We are now ready to accept transmit requeusts from
+	 * the queueing layer of the networking.
+	 */
+	netif_start_queue(dev);
+
+	return 0;
+}
+
+
+static void
+e100_check_speed(unsigned long dummy)
+{
+	unsigned long data;
+	data = e100_get_mdio_reg(MDIO_BASE_STATUS_REG);
+	if (!(data & MDIO_LINK_UP_MASK)) {
+		nolink = 1;
+		LED_NETWORK_TX_SET(1); /* Make it red, link is down. */
+	} else {
+		nolink = 0;
+		LED_NETWORK_TX_SET(0); /* Link is up again, clear red LED. */
+		data = e100_get_mdio_reg(MDIO_AUX_CTRL_STATUS_REG);
+		if (data & MDIO_SPEED) {
+			current_speed = 100;
+		} else {
+			current_speed = 10;
+		}
+	}
+	
+	/* Reinitialize the timer. */
+	speed_timer.expires = jiffies + NET_LINK_UP_CHECK_INTERVAL;
+	add_timer(&speed_timer);
+}
+
+static unsigned short
+e100_get_mdio_reg(unsigned char reg_num)
+{
+	unsigned long flags;
+	unsigned short cmd;    /* Data to be sent on MDIO port */
+	unsigned short data;   /* Data read from MDIO */
+	int bitCounter;
+	
+	save_flags(flags);
+	cli();
+	
+	/* Start of frame, OP Code, Physical Address, Register Address */
+	cmd = (MDIO_START << 14) | (MDIO_READ << 12) | (MDIO_PHYS_ADDR << 7) |
+		(reg_num << 2);
+	
+	e100_send_mdio_cmd(cmd, 0);
+	
+	data = 0;
+	
+	/* Data... */
+	for(bitCounter=15; bitCounter>=0 ; bitCounter--) {
+		data |= (e100_receive_mdio_bit() << bitCounter);
+	}
+	
+	restore_flags(flags);
+	return data;
+}
+
+static void
+e100_send_mdio_cmd(unsigned short cmd, int write_cmd)
+{
+	int bitCounter;
+	unsigned char data = 0x2;
+	
+	/* Preamble */
+	for(bitCounter = 31; bitCounter>= 0; bitCounter--)
+		e100_send_mdio_bit(GET_BIT(bitCounter, MDIO_PREAMBLE));
+
+	for(bitCounter = 15; bitCounter >= 2; bitCounter--)
+		e100_send_mdio_bit(GET_BIT(bitCounter, cmd));
+
+	/* Turnaround */
+	for(bitCounter = 1; bitCounter >= 0 ; bitCounter--)
+		if (write_cmd)
+			e100_send_mdio_bit(GET_BIT(bitCounter, data));
+		else
+			e100_receive_mdio_bit();
+}
+
+static void
+e100_send_mdio_bit(unsigned char bit)
+{
+	volatile int i;
+	*R_NETWORK_MGM_CTRL = 2 | bit&1;
+	for (i=40; i; i--);
+	*R_NETWORK_MGM_CTRL = 6 | bit&1;
+	for (i=40; i; i--);
+}
+
+static unsigned char
+e100_receive_mdio_bit()
+{
+	unsigned char bit;
+	volatile int i;
+	*R_NETWORK_MGM_CTRL = 0;
+	bit = *R_NETWORK_STAT & 1;
+	for (i=40; i; i--);
+	*R_NETWORK_MGM_CTRL = 4;
+	for (i=40; i; i--);
+	return bit;
+}
+
+static void 
+e100_reset_tranceiver(void)
+{
+	unsigned long flags;
+	unsigned short cmd;
+	unsigned short data;
+	int bitCounter;
+
+	save_flags(flags);
+	cli();
+
+	data = e100_get_mdio_reg(MDIO_BASE_CONTROL_REG);
+
+	cmd = (MDIO_START << 14) | (MDIO_WRITE << 12) | (MDIO_PHYS_ADDR << 7) | (MDIO_BASE_CONTROL_REG << 2);
+
+	e100_send_mdio_cmd(cmd, 0);
+	
+	data |= 0x8000;
+	
+	for(bitCounter = 15; bitCounter >= 0 ; bitCounter--) {
+		e100_send_mdio_bit(GET_BIT(bitCounter, data));
+	}
+	
+	restore_flags(flags);
+}
+
+/* Called by upper layers if they decide it took too long to complete
+ * sending a packet - we need to reset and stuff.
+ */
+
+static void
+e100_tx_timeout(struct net_device *dev)
+{
+	struct net_local *np = (struct net_local *)dev->priv;
+
+	printk(KERN_WARNING "%s: transmit timed out, %s?\n", dev->name,
+	       tx_done(dev) ? "IRQ problem" : "network cable problem");
+	
+	/* remember we got an error */
+	
+	np->stats.tx_errors++; 
+	
+	/* reset the TX DMA in case it has hung on something */
+	
+	RESET_DMA(0);
+	WAIT_DMA(0);
+	
+	/* Reset the tranceiver. */
+	
+	e100_reset_tranceiver();
+	
+	/* and get rid of the packet that never got an interrupt */
+	
+	dev_kfree_skb(tx_skb);
+	tx_skb = 0;
+	
+	/* tell the upper layers we're ok again */
+	
+	netif_wake_queue(dev);
+}
+
+
+/* This will only be invoked if the driver is _not_ in XOFF state.
+ * What this means is that we need not check it, and that this
+ * invariant will hold if we make sure that the netif_*_queue()
+ * calls are done at the proper times.
+ */
+
+static int
+e100_send_packet(struct sk_buff *skb, struct net_device *dev)
+{
+	struct net_local *np = (struct net_local *)dev->priv;
+	int length = ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN;
+	unsigned char *buf = skb->data;
+	
+#ifdef ETHDEBUG
+	printk("send packet len %d\n", length);
+#endif
+	spin_lock_irq(&np->lock);  /* protect from tx_interrupt */
+
+	tx_skb = skb; /* remember it so we can free it in the tx irq handler later */
+	dev->trans_start = jiffies;
+	
+	e100_hardware_send_packet(buf, length);
+
+	/* this simple TX driver has only one send-descriptor so we're full
+	 * directly. If this had a send-ring instead, we would only do this if
+	 * the ring got full.
+	 */
+
+	netif_stop_queue(dev);
+
+	spin_unlock_irq(&np->lock);
+
+	return 0;
+}
+
+/*
+ * The typical workload of the driver:
+ *   Handle the network interface interrupts.
+ */
+
+static void
+e100rx_interrupt(int irq, void *dev_id, struct pt_regs * regs)
+{
+	struct net_device *dev = (struct net_device *)dev_id;
+	unsigned long irqbits = *R_IRQ_MASK2_RD;
+
+	if(irqbits & (1U << 3)) {
+
+		/* acknowledge the eop interrupt */
+
+		*R_DMA_CH1_CLR_INTR = IO_STATE(R_DMA_CH1_CLR_INTR, clr_eop, do);
+
+		/* check if one or more complete packets were indeed received */
+
+		while(*R_DMA_CH1_FIRST != virt_to_phys(myNextRxDesc)) {
+			/* Take out the buffer and give it to the OS, then
+			 * allocate a new buffer to put a packet in.
+			 */
+			e100_rx(dev);
+			((struct net_local *)dev->priv)->stats.rx_packets++;
+			*R_DMA_CH1_CMD = 3; /* restart/continue on the channel, for safety */
+			*R_DMA_CH1_CLR_INTR = 3; /* clear dma channel 1 eop/descr irq bits */
+			/* now, we might have gotten another packet so we have to loop back
+			   and check if so */
+		}
+	}
+}
+
+/* the transmit dma channel interrupt
+ *
+ * this is supposed to free the skbuff which was pending during transmission,
+ * and inform the kernel that we can send one more buffer
+ */
+
+static void
+e100tx_interrupt(int irq, void *dev_id, struct pt_regs * regs)
+{
+	struct net_device *dev = (struct net_device *)dev_id;
+	unsigned long irqbits = *R_IRQ_MASK2_RD;
+	struct net_local *np = (struct net_local *)dev->priv;
+
+	if(irqbits & 2) { /* check for a dma0_eop interrupt */
+
+		/* This protects us from concurrent execution of
+		 * our dev->hard_start_xmit function above.
+		 */
+
+		spin_lock(&np->lock);
+		
+		/* acknowledge the eop interrupt */
+
+		*R_DMA_CH0_CLR_INTR = IO_STATE(R_DMA_CH0_CLR_INTR, clr_eop, do);
+
+		if(*R_DMA_CH0_FIRST == 0 && tx_skb) {
+			np->stats.tx_bytes += tx_skb->len;
+			np->stats.tx_packets++;
+			/* dma is ready with the transmission of the data in tx_skb, so now
+			   we can release the skb memory */
+			dev_kfree_skb_irq(tx_skb);
+			tx_skb = 0;
+			netif_wake_queue(dev);
+		} else {
+			printk("tx weird interrupt\n");
+		}
+
+		spin_unlock(&np->lock);
+	}
+}
+
+static void
+e100nw_interrupt(int irq, void *dev_id, struct pt_regs * regs)
+{
+	struct net_device *dev = (struct net_device *)dev_id;
+	struct net_local *np = (struct net_local *)dev->priv;
+	unsigned long irqbits = *R_IRQ_MASK0_RD;
+
+	if(irqbits & (1 << 19)) { /* check for overrun irq */
+		update_rx_stats(&np->stats); /* this will ack the irq */
+		D(printk("ethernet receiver overrun!\n"));
+	}
+	if(irqbits & (1 << 17)) { /* check for excessive collision irq */
+		*R_NETWORK_TR_CTRL = 1 << 8; /* clear the interrupt */
+		np->stats.tx_errors++;
+		D(printk("ethernet excessive collisions!\n"));
+	}
+
+}
+
+/* We have a good packet(s), get it/them out of the buffers. */
+static void
+e100_rx(struct net_device *dev)
+{
+	struct sk_buff *skb;
+	int length=0;
+	int i;
+	struct etrax_dma_descr *mySaveRxDesc = myNextRxDesc;
+	unsigned char *skb_data_ptr;
+
+	/* light the network rx packet depending on the current speed.
+	** But only if link has been detected.
+	*/
+	if (!nolink)
+		if (current_speed == 10) {
+			LED_NETWORK_TX_SET(1);
+			LED_NETWORK_RX_SET(1);
+		} else
+			LED_NETWORK_RX_SET(1);
+  
+	/* Set the earliest time we may clear the LED */
+
+	led_clear_time = jiffies + NET_FLASH_TIME;
+  
+	/* If the packet is broken down in many small packages then merge
+	 * count how much space we will need to alloc with skb_alloc() for
+	 * it to fit.
+	 */
+
+	while (!(myNextRxDesc->status & d_eop)) {
+		length += myNextRxDesc->sw_len; /* use sw_len for the first descs */
+		myNextRxDesc->status = 0;
+		myNextRxDesc = phys_to_virt(myNextRxDesc->next);
+	}
+
+	length += myNextRxDesc->hw_len; /* use hw_len for the last descr */
+
+#ifdef ETHDEBUG
+	printk("Got a packet of length %d:\n", length);
+	/* dump the first bytes in the packet */
+	skb_data_ptr = (unsigned char *)phys_to_virt(mySaveRxDesc->buf);
+	for(i = 0; i < 8; i++) {
+		printk("%d: %.2x %.2x %.2x %.2x %.2x %.2x %.2x %.2x\n", i * 8,
+		       skb_data_ptr[0],skb_data_ptr[1],skb_data_ptr[2],skb_data_ptr[3],
+		       skb_data_ptr[4],skb_data_ptr[5],skb_data_ptr[6],skb_data_ptr[7]);
+		skb_data_ptr += 8;
+	}
+#endif
+
+	skb = dev_alloc_skb(length - ETHER_HEAD_LEN);
+	if (!skb) {
+		printk(KERN_NOTICE "%s: Memory squeeze, dropping packet.\n",
+		       dev->name);
+		return;
+	}
+
+	skb_put(skb, length - ETHER_HEAD_LEN);        /* allocate room for the packet body */
+	skb_data_ptr = skb_push(skb, ETHER_HEAD_LEN); /* allocate room for the header */
+
+#if 0
+	printk("head = 0x%x, data = 0x%x, tail = 0x%x, end = 0x%x\n",
+	       skb->head, skb->data, skb->tail, skb->end);
+	printk("copying packet to 0x%x.\n", skb_data_ptr);
+#endif
+
+	/* this loop can be made using max two memcpy's if optimized */
+
+	while(mySaveRxDesc != myNextRxDesc) {
+		memcpy(skb_data_ptr, phys_to_virt(mySaveRxDesc->buf),
+		       mySaveRxDesc->sw_len);
+		skb_data_ptr += mySaveRxDesc->sw_len;
+		mySaveRxDesc = phys_to_virt(mySaveRxDesc->next);
+	}
+
+	memcpy(skb_data_ptr, phys_to_virt(mySaveRxDesc->buf),
+	       mySaveRxDesc->hw_len);
+
+	skb->dev = dev;
+	skb->protocol = eth_type_trans(skb, dev);
+
+	/* Send the packet to the upper layers */
+
+	netif_rx(skb);
+
+	/* Prepare for next packet */
+
+	myNextRxDesc->status = 0;
+	myPrevRxDesc = myNextRxDesc;
+	myNextRxDesc = phys_to_virt(myNextRxDesc->next);
+
+	myPrevRxDesc->ctrl |= d_eol;
+	myLastRxDesc->ctrl &= ~d_eol;
+	myLastRxDesc = myPrevRxDesc;
+
+	return;
+}
+
+/* The inverse routine to net_open(). */
+static int
+e100_close(struct net_device *dev)
+{
+	struct net_local *np = (struct net_local *)dev->priv;
+
+	printk("Closing %s.\n", dev->name);
+
+	netif_stop_queue(dev);
+
+	*R_NETWORK_GEN_CONFIG =
+		IO_STATE(R_NETWORK_GEN_CONFIG, phy,    mii_clk) |
+		IO_STATE(R_NETWORK_GEN_CONFIG, enable, off);
+
+	*R_IRQ_MASK0_CLR = 0xe0000; /* clear excessive_col, over/underrun irq mask */
+	*R_IRQ_MASK2_CLR = 0xf; /* clear dma0 and 1 eop and descr irq masks */
+
+	/* Stop the receiver and the transmitter */
+
+	RESET_DMA(0);
+	RESET_DMA(1);
+
+	/* Flush the Tx and disable Rx here. */
+
+	free_irq(NETWORK_DMARX_IRQ, NULL);
+	free_irq(NETWORK_DMATX_IRQ, NULL);
+	free_irq(NETWORK_STATUS_IRQ, NULL);
+
+	free_dma(0);
+	free_dma(1);
+
+	/* Update the statistics here. */
+
+	update_rx_stats(&np->stats);
+	update_tx_stats(&np->stats);
+
+	return 0;
+}
+
+static void
+update_rx_stats(struct net_device_stats *es)
+{
+	unsigned long r = *R_REC_COUNTERS;
+	/* update stats relevant to reception errors */
+	es->rx_fifo_errors += r >> 24;            /* fifo overrun */
+	es->rx_crc_errors += r & 0xff;            /* crc error */
+	es->rx_frame_errors += (r >> 8) & 0xff;   /* alignment error */
+	es->rx_length_errors += (r >> 16) & 0xff; /* oversized frames */
+}
+
+static void
+update_tx_stats(struct net_device_stats *es)
+{
+	unsigned long r = *R_TR_COUNTERS;
+	/* update stats relevant to transmission errors */
+	es->collisions += (r & 0xff) + ((r >> 8) & 0xff); /* single_col + multiple_col */
+	es->tx_errors += (r >> 24) & 0xff; /* deferred transmit frames */
+}
+
+/*
+ * Get the current statistics.
+ * This may be called with the card open or closed.
+ */
+static struct net_device_stats *
+e100_get_stats(struct net_device *dev)
+{
+	struct net_local *lp = (struct net_local *)dev->priv;
+
+	update_rx_stats(&lp->stats);
+	update_tx_stats(&lp->stats);
+
+	return &lp->stats;
+}
+
+/*
+ * Set or clear the multicast filter for this adaptor.
+ * num_addrs == -1	Promiscuous mode, receive all packets
+ * num_addrs == 0	Normal mode, clear multicast list
+ * num_addrs > 0	Multicast mode, receive normal and MC packets,
+ *			and do best-effort filtering.
+ */
+static void
+set_multicast_list(struct net_device *dev)
+{
+	int num_addr = dev->mc_count;
+	unsigned long int lo_bits;
+	unsigned long int hi_bits;
+	if (num_addr == -1)
+	{
+		/* promiscuous mode */
+		lo_bits = 0xfffffffful;
+		hi_bits = 0xfffffffful;
+	} else if (num_addr == 0) {
+		/* Normal, clear the mc list */
+		lo_bits = 0x00000000ul;
+		hi_bits = 0x00000000ul;
+	} else {
+		/* MC mode, receive normal and MC packets */
+		char hash_ix;
+		struct dev_mc_list *dmi = dev->mc_list;
+		int i;
+		char *baddr;
+		lo_bits = 0x00000000ul;
+		hi_bits = 0x00000000ul;
+		for (i=0; i<num_addr; i++) {
+			/* Calculate the hash index for the GA registers */
+			
+			hash_ix = 0;
+			baddr = dmi->dmi_addr;
+			hash_ix ^= (*baddr) & 0x3f;
+			hash_ix ^= ((*baddr) >> 6) & 0x03;
+			++baddr;
+			hash_ix ^= ((*baddr) << 2) & 0x03c;
+			hash_ix ^= ((*baddr) >> 4) & 0xf;
+			++baddr;
+			hash_ix ^= ((*baddr) << 4) & 0x30;
+			hash_ix ^= ((*baddr) >> 2) & 0x3f;
+			++baddr;
+			hash_ix ^= (*baddr) & 0x3f;
+			hash_ix ^= ((*baddr) >> 6) & 0x03;
+			++baddr;
+			hash_ix ^= ((*baddr) << 2) & 0x03c;
+			hash_ix ^= ((*baddr) >> 4) & 0xf;
+			++baddr;
+			hash_ix ^= ((*baddr) << 4) & 0x30;
+			hash_ix ^= ((*baddr) >> 2) & 0x3f;
+			
+			hash_ix &= 0x3f;
+			
+			if (hash_ix > 32) {
+				hi_bits |= (1 << (hash_ix-32));
+			}
+			else {
+				lo_bits |= (1 << hash_ix);
+			}
+			dmi = dmi->next;
+		}
+	}
+	*R_NETWORK_GA_0 = lo_bits;
+	*R_NETWORK_GA_1 = hi_bits;
+}
+
+void
+e100_hardware_send_packet(char *buf, int length)
+{
+	D(printk("e100 send pack, buf 0x%x len %d\n", buf, length));
+	/* light the network leds depending on the current speed.
+	** But only if link has been detected.
+	*/
+	if (!nolink) {
+		if (current_speed == 10) {
+			LED_NETWORK_TX_SET(1);
+			LED_NETWORK_RX_SET(1);
+		} else {
+			LED_NETWORK_RX_SET(1);
+		}
+	}
+
+	/* Set the earliest time we may clear the LED */
+
+	led_clear_time = jiffies + NET_FLASH_TIME;
+	
+	/* configure the tx dma descriptor */
+
+	TxDesc.sw_len = length;
+	TxDesc.ctrl = d_eop | d_eol | d_wait;
+	TxDesc.buf = virt_to_phys(buf);
+
+	/* setup the dma channel and start it */
+
+	*R_DMA_CH0_FIRST = virt_to_phys(&TxDesc);
+	*R_DMA_CH0_CMD = IO_STATE(R_DMA_CH0_CMD, cmd, start);
+}
+
+static void
+e100_clear_network_leds(unsigned long dummy)
+{
+	if (jiffies > led_clear_time) {
+		if (nolink)
+			LED_NETWORK_TX_SET(1);
+		else
+			LED_NETWORK_TX_SET(0);
+		LED_NETWORK_RX_SET(0); 
+	}
+	
+	clear_led_timer.expires = jiffies + 10;
+	add_timer(&clear_led_timer);
+}
+
+static struct net_device dev_etrax_ethernet;  /* only got one */
+
+static int
+etrax_init_module(void)
+{
+	struct net_device *d = &dev_etrax_ethernet;
+
+	d->init = etrax_ethernet_init;
+
+	if(register_netdev(d) == 0)
+		return 0;
+	else
+		return -ENODEV;
+}
+
+module_init(etrax_init_module);

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)