rrunner.c

讲述linux的初始化过程

	writel(io, &regs->ExtIo);
	mb();

	return error;
}


static int __init rr_init(struct net_device *dev)
{
	struct rr_private *rrpriv;
	struct rr_regs *regs;
	struct eeprom *hw = NULL;
	u32 sram_size, rev;
	int i;

	rrpriv = (struct rr_private *)dev->priv;
	regs = rrpriv->regs;

	rev = readl(&regs->FwRev);
	rrpriv->fw_rev = rev;
	if (rev > 0x00020024)
		printk("  Firmware revision: %i.%i.%i\n", (rev >> 16),
		       ((rev >> 8) & 0xff), (rev & 0xff));
	else if (rev >= 0x00020000) {
		printk("  Firmware revision: %i.%i.%i (2.0.37 or "
		       "later is recommended)\n", (rev >> 16),
		       ((rev >> 8) & 0xff), (rev & 0xff));
	}else{
		printk("  Firmware revision too old: %i.%i.%i, please "
		       "upgrade to 2.0.37 or later.\n",
		       (rev >> 16), ((rev >> 8) & 0xff), (rev & 0xff));
	}

#if (DEBUG > 2)
	printk("  Maximum receive rings %i\n", readl(&regs->MaxRxRng));
#endif

	/*
	 * Read the hardware address from the eeprom.  The HW address
	 * is not really necessary for HIPPI but awfully convenient.
	 * The pointer arithmetic to put it in dev_addr is ugly, but
	 * Donald Becker does it this way for the GigE version of this
	 * card and it's shorter and more portable than any
	 * other method I've seen.  -VAL
	 */

	*(u16 *)(dev->dev_addr) =
	  htons(rr_read_eeprom_word(rrpriv, &hw->manf.BoardULA));
	*(u32 *)(dev->dev_addr+2) =
	  htonl(rr_read_eeprom_word(rrpriv, &hw->manf.BoardULA[4]));
	
	printk("  MAC: ");

	for (i = 0; i < 5; i++)
		printk("%2.2x:", dev->dev_addr[i]);
	printk("%2.2x\n", dev->dev_addr[i]);

	sram_size = rr_read_eeprom_word(rrpriv, (void *)8);
	printk("  SRAM size 0x%06x\n", sram_size);

	if (sysctl_rmem_max < 262144){
		printk("  Receive socket buffer limit too low (%i), "
		       "setting to 262144\n", sysctl_rmem_max);
		sysctl_rmem_max = 262144;
	}

	if (sysctl_wmem_max < 262144){
		printk("  Transmit socket buffer limit too low (%i), "
		       "setting to 262144\n", sysctl_wmem_max);
		sysctl_wmem_max = 262144;
	}

	rrpriv->next = root_dev;
	root_dev = dev;

	return 0;
}


static int rr_init1(struct net_device *dev)
{
	struct rr_private *rrpriv;
	struct rr_regs *regs;
	unsigned long myjif, flags;
	struct cmd cmd;
	u32 hostctrl;
	int ecode = 0;
	short i;

	rrpriv = (struct rr_private *)dev->priv;
	regs = rrpriv->regs;

	spin_lock_irqsave(&rrpriv->lock, flags);

	hostctrl = readl(&regs->HostCtrl);
	writel(hostctrl | HALT_NIC | RR_CLEAR_INT, &regs->HostCtrl);
	wmb();

	if (hostctrl & PARITY_ERR){
		printk("%s: Parity error halting NIC - this is serious!\n",
		       dev->name);
		spin_unlock_irqrestore(&rrpriv->lock, flags);
		ecode = -EFAULT;
		goto error;
	}

	set_rxaddr(regs, rrpriv->rx_ctrl);
	set_infoaddr(regs, rrpriv->info);

	rrpriv->info->evt_ctrl.entry_size = sizeof(struct event);
	rrpriv->info->evt_ctrl.entries = EVT_RING_ENTRIES;
	rrpriv->info->evt_ctrl.mode = 0;
	rrpriv->info->evt_ctrl.pi = 0;
	set_rraddr(&rrpriv->info->evt_ctrl.rngptr, rrpriv->evt_ring);

	rrpriv->info->cmd_ctrl.entry_size = sizeof(struct cmd);
	rrpriv->info->cmd_ctrl.entries = CMD_RING_ENTRIES;
	rrpriv->info->cmd_ctrl.mode = 0;
	rrpriv->info->cmd_ctrl.pi = 15;

	for (i = 0; i < CMD_RING_ENTRIES; i++) {
		writel(0, &regs->CmdRing[i]);
	}

	for (i = 0; i < TX_RING_ENTRIES; i++) {
		rrpriv->tx_ring[i].size = 0;
		set_rraddr(&rrpriv->tx_ring[i].addr, 0);
		rrpriv->tx_skbuff[i] = 0;
	}
	rrpriv->info->tx_ctrl.entry_size = sizeof(struct tx_desc);
	rrpriv->info->tx_ctrl.entries = TX_RING_ENTRIES;
	rrpriv->info->tx_ctrl.mode = 0;
	rrpriv->info->tx_ctrl.pi = 0;
	set_rraddr(&rrpriv->info->tx_ctrl.rngptr, rrpriv->tx_ring);

	/*
	 * Set dirty_tx before we start receiving interrupts, otherwise
	 * the interrupt handler might think it is supposed to process
	 * tx ints before we are up and running, which may cause a null
	 * pointer access in the int handler.
	 */
	rrpriv->tx_full = 0;
	rrpriv->cur_rx = 0;
	rrpriv->dirty_rx = rrpriv->dirty_tx = 0;

	rr_reset(dev);

	/* Tuning values */
	writel(0x5000, &regs->ConRetry);
	writel(0x100, &regs->ConRetryTmr);
	writel(0x500000, &regs->ConTmout);
 	writel(0x60, &regs->IntrTmr);
	writel(0x500000, &regs->TxDataMvTimeout);
	writel(0x200000, &regs->RxDataMvTimeout);
 	writel(0x80, &regs->WriteDmaThresh);
 	writel(0x80, &regs->ReadDmaThresh);

	rrpriv->fw_running = 0;
	wmb();

	hostctrl &= ~(HALT_NIC | INVALID_INST_B | PARITY_ERR);
	writel(hostctrl, &regs->HostCtrl);
	wmb();

	spin_unlock_irqrestore(&rrpriv->lock, flags);

	for (i = 0; i < RX_RING_ENTRIES; i++) {
		struct sk_buff *skb;

		rrpriv->rx_ring[i].mode = 0;
		skb = alloc_skb(dev->mtu + HIPPI_HLEN, GFP_ATOMIC);
		if (!skb) {
			printk(KERN_WARNING "%s: Unable to allocate memory "
			       "for receive ring - halting NIC\n", dev->name);
			ecode = -ENOMEM;
			goto error;
		}
		rrpriv->rx_skbuff[i] = skb;
		/*
		 * Sanity test to see if we conflict with the DMA
		 * limitations of the Roadrunner.
		 */
		if ((((unsigned long)skb->data) & 0xfff) > ~65320)
			printk("skb alloc error\n");

		set_rraddr(&rrpriv->rx_ring[i].addr, skb->data);
		rrpriv->rx_ring[i].size = dev->mtu + HIPPI_HLEN;
	}

	rrpriv->rx_ctrl[4].entry_size = sizeof(struct rx_desc);
	rrpriv->rx_ctrl[4].entries = RX_RING_ENTRIES;
	rrpriv->rx_ctrl[4].mode = 8;
	rrpriv->rx_ctrl[4].pi = 0;
	wmb();
	set_rraddr(&rrpriv->rx_ctrl[4].rngptr, rrpriv->rx_ring);

	udelay(1000);

	/*
	 * Now start the FirmWare.
	 */
	cmd.code = C_START_FW;
	cmd.ring = 0;
	cmd.index = 0;

	rr_issue_cmd(rrpriv, &cmd);

	/*
	 * Give the FirmWare time to chew on the `get running' command.
	 */
	myjif = jiffies + 5 * HZ;
	while ((jiffies < myjif) && !rrpriv->fw_running);

	netif_start_queue(dev);

	return ecode;

 error:
	/*
	 * We might have gotten here because we are out of memory,
	 * make sure we release everything we allocated before failing
	 */
	for (i = 0; i < RX_RING_ENTRIES; i++) {
		if (rrpriv->rx_skbuff[i]) {
			rrpriv->rx_ring[i].size = 0;
			set_rraddr(&rrpriv->rx_ring[i].addr, 0);
			dev_kfree_skb(rrpriv->rx_skbuff[i]);
		}
	}
	return ecode;
}


/*
 * All events are considered to be slow (RX/TX ints do not generate
 * events) and are handled here, outside the main interrupt handler,
 * to reduce the size of the handler.
 */
static u32 rr_handle_event(struct net_device *dev, u32 prodidx, u32 eidx)
{
	struct rr_private *rrpriv;
	struct rr_regs *regs;
	u32 tmp;

	rrpriv = (struct rr_private *)dev->priv;
	regs = rrpriv->regs;

	while (prodidx != eidx){
		switch (rrpriv->evt_ring[eidx].code){
		case E_NIC_UP:
			tmp = readl(&regs->FwRev);
			printk(KERN_INFO "%s: Firmware revision %i.%i.%i "
			       "up and running\n", dev->name,
			       (tmp >> 16), ((tmp >> 8) & 0xff), (tmp & 0xff));
			rrpriv->fw_running = 1;
			writel(RX_RING_ENTRIES - 1, &regs->IpRxPi);
			wmb();
			break;
		case E_LINK_ON:
			printk(KERN_INFO "%s: Optical link ON\n", dev->name);
			break;
		case E_LINK_OFF:
			printk(KERN_INFO "%s: Optical link OFF\n", dev->name);
			break;
		case E_RX_IDLE:
			printk(KERN_WARNING "%s: RX data not moving\n",
			       dev->name);
			break;
		case E_WATCHDOG:
			printk(KERN_INFO "%s: The watchdog is here to see "
			       "us\n", dev->name);
			break;
		case E_INTERN_ERR:
			printk(KERN_ERR "%s: HIPPI Internal NIC error\n",
			       dev->name);
			writel(readl(&regs->HostCtrl)|HALT_NIC|RR_CLEAR_INT, 
			       &regs->HostCtrl);
			wmb();
			break;
		case E_HOST_ERR:
			printk(KERN_ERR "%s: Host software error\n",
			       dev->name);
			writel(readl(&regs->HostCtrl)|HALT_NIC|RR_CLEAR_INT, 
			       &regs->HostCtrl);
			wmb();
			break;
		/*
		 * TX events.
		 */
		case E_CON_REJ:
			printk(KERN_WARNING "%s: Connection rejected\n",
			       dev->name);
			rrpriv->stats.tx_aborted_errors++;
			break;
		case E_CON_TMOUT:
			printk(KERN_WARNING "%s: Connection timeout\n",
			       dev->name);
			break;
		case E_DISC_ERR:
			printk(KERN_WARNING "%s: HIPPI disconnect error\n",
			       dev->name);
			rrpriv->stats.tx_aborted_errors++;
			break;
		case E_INT_PRTY:
			printk(KERN_ERR "%s: HIPPI Internal Parity error\n",
			       dev->name);
			writel(readl(&regs->HostCtrl)|HALT_NIC|RR_CLEAR_INT, 
			       &regs->HostCtrl);
			wmb();
			break;
		case E_TX_IDLE:
			printk(KERN_WARNING "%s: Transmitter idle\n",
			       dev->name);
			break;
		case E_TX_LINK_DROP:
			printk(KERN_WARNING "%s: Link lost during transmit\n",
			       dev->name);
			rrpriv->stats.tx_aborted_errors++;
			writel(readl(&regs->HostCtrl)|HALT_NIC|RR_CLEAR_INT, 
			       &regs->HostCtrl);
			wmb();
			break;
		case E_TX_INV_RNG:
			printk(KERN_ERR "%s: Invalid send ring block\n",
			       dev->name);
			writel(readl(&regs->HostCtrl)|HALT_NIC|RR_CLEAR_INT, 
			       &regs->HostCtrl);
			wmb();
			break;
		case E_TX_INV_BUF:
			printk(KERN_ERR "%s: Invalid send buffer address\n",
			       dev->name);
			writel(readl(&regs->HostCtrl)|HALT_NIC|RR_CLEAR_INT, 
			       &regs->HostCtrl);
			wmb();
			break;
		case E_TX_INV_DSC:
			printk(KERN_ERR "%s: Invalid descriptor address\n",
			       dev->name);
			writel(readl(&regs->HostCtrl)|HALT_NIC|RR_CLEAR_INT, 
			       &regs->HostCtrl);
			wmb();
			break;
		/*
		 * RX events.
		 */
		case E_RX_RNG_OUT:
			printk(KERN_INFO "%s: Receive ring full\n", dev->name);
			break;

		case E_RX_PAR_ERR:
			printk(KERN_WARNING "%s: Receive parity error\n",
			       dev->name);
			break;
		case E_RX_LLRC_ERR:
			printk(KERN_WARNING "%s: Receive LLRC error\n",
			       dev->name);
			break;
		case E_PKT_LN_ERR:
			printk(KERN_WARNING "%s: Receive packet length "
			       "error\n", dev->name);
			break;
		case E_RX_INV_BUF:
			printk(KERN_ERR "%s: Invalid receive buffer "
			       "address\n", dev->name);
			writel(readl(&regs->HostCtrl)|HALT_NIC|RR_CLEAR_INT, 
			       &regs->HostCtrl);
			wmb();
			break;
		case E_RX_INV_DSC:
			printk(KERN_ERR "%s: Invalid receive descriptor "
			       "address\n", dev->name);
			writel(readl(&regs->HostCtrl)|HALT_NIC|RR_CLEAR_INT, 
			       &regs->HostCtrl);
			wmb();
			break;
		case E_RNG_BLK:
			printk(KERN_ERR "%s: Invalid ring block\n",
			       dev->name);
			writel(readl(&regs->HostCtrl)|HALT_NIC|RR_CLEAR_INT, 
			       &regs->HostCtrl);
			wmb();
			break;
		default:
			printk(KERN_WARNING "%s: Unhandled event 0x%02x\n",
			       dev->name, rrpriv->evt_ring[eidx].code);
		}
		eidx = (eidx + 1) % EVT_RING_ENTRIES;
	}

	rrpriv->info->evt_ctrl.pi = eidx;
	wmb();
	return eidx;
}


static void rx_int(struct net_device *dev, u32 rxlimit, u32 index)
{
	struct rr_private *rrpriv = (struct rr_private *)dev->priv;
	struct rr_regs *regs = rrpriv->regs;

	do {
		u32 pkt_len;
		pkt_len = rrpriv->rx_ring[index].size;
#if (DEBUG > 2)
		printk("index %i, rxlimit %i\n", index, rxlimit);
		printk("len %x, mode %x\n", pkt_len,
		       rrpriv->rx_ring[index].mode);
#endif
		if (pkt_len > 0){
			struct sk_buff *skb;

			if (pkt_len < PKT_COPY_THRESHOLD) {
				skb = alloc_skb(pkt_len, GFP_ATOMIC);
				if (skb == NULL){
					printk(KERN_WARNING "%s: Unable to allocate skb (%i bytes), deferring packet\n", dev->name, pkt_len);
					rrpriv->stats.rx_dropped++;
					goto defer;
				}else
					memcpy(skb_put(skb, pkt_len),
					       rrpriv->rx_skbuff[index]->data,
					       pkt_len);
			}else{
				struct sk_buff *newskb;

				newskb = alloc_skb(dev->mtu + HIPPI_HLEN,
						   GFP_ATOMIC);
				if (newskb){
					skb = rrpriv->rx_skbuff[index];
					skb_put(skb, pkt_len);
					rrpriv->rx_skbuff[index] = newskb;
					set_rraddr(&rrpriv->rx_ring[index].addr, newskb->data);
				}else{
					printk("%s: Out of memory, deferring "
					       "packet\n", dev->name);
					rrpriv->stats.rx_dropped++;
					goto defer;
				}
			}
			skb->dev = dev;
			skb->protocol = hippi_type_trans(skb, dev);

			netif_rx(skb);		/* send it up */

			rrpriv->stats.rx_packets++;
			rrpriv->stats.rx_bytes += skb->len;
		}
	defer:
		rrpriv->rx_ring[index].mode = 0;
		rrpriv->rx_ring[index].size = dev->mtu + HIPPI_HLEN;

		if ((index & 7) == 7)
			writel(index, &regs->IpRxPi);

		index = (index + 1) % RX_RING_ENTRIES;
	} while(index != rxlimit);

	rrpriv->cur_rx = index;
	wmb();
}


static void rr_interrupt(int irq, void *dev_id, struct pt_regs *ptregs)
{
	struct rr_private *rrpriv;
	struct rr_regs *regs;
	struct net_device *dev = (struct net_device *)dev_id;
	u32 prodidx, rxindex, eidx, txcsmr, rxlimit, txcon;

	rrpriv = (struct rr_private *)dev->priv;
	regs = rrpriv->regs;

	if (!(readl(&regs->HostCtrl) & RR_INT))
		return;

	spin_lock(&rrpriv->lock);

	prodidx = readl(&regs->EvtPrd);
	txcsmr = (prodidx >> 8) & 0xff;
	rxlimit = (prodidx >> 16) & 0xff;
	prodidx &= 0xff;

#if (DEBUG > 2)
	printk("%s: interrupt, prodidx = %i, eidx = %i\n", dev->name,
	       prodidx, rrpriv->info->evt_ctrl.pi);
#endif

	rxindex = rrpriv->cur_rx;
	if (rxindex != rxlimit)
		rx_int(dev, rxlimit, rxindex);

	txcon = rrpriv->dirty_tx;
	if (txcsmr != txcon) {
		do {
			rrpriv->stats.tx_packets++;
			rrpriv->stats.tx_bytes +=rrpriv->tx_skbuff[txcon]->len;
			dev_kfree_skb_irq(rrpriv->tx_skbuff[txcon]);

			rrpriv->tx_skbuff[txcon] = NULL;
			rrpriv->tx_ring[txcon].size = 0;
			set_rraddr(&rrpriv->tx_ring[txcon].addr, 0);
			rrpriv->tx_ring[txcon].mode = 0;

			txcon = (txcon + 1) % TX_RING_ENTRIES;
		} while (txcsmr != txcon);
		wmb();

		rrpriv->dirty_tx = txcon;
		if (rrpriv->tx_full && rr_if_busy(dev) &&
		    (((rrpriv->info->tx_ctrl.pi + 1) % TX_RING_ENTRIES)
		     != rrpriv->dirty_tx)){
			rrpriv->tx_full = 0;
			netif_wake_queue(dev);
			rr_mark_net_bh(NET_BH);
		}
	}

	eidx = rrpriv->info->evt_ctrl.pi;
	if (prodidx != eidx)
		eidx = rr_handle_event(dev, prodidx, eidx);

	eidx |= ((txcsmr << 8) | (rxlimit << 16));
	writel(eidx, &regs->EvtCon);
	wmb();

	spin_unlock(&rrpriv->lock);
}


static void rr_timer(unsigned long data)
{
	struct net_device *dev = (struct net_device *)data;
	struct rr_private *rrpriv = (struct rr_private *)dev->priv;
	struct rr_regs *regs = rrpriv->regs;
	unsigned long flags;
	int i;

	if (readl(&regs->HostCtrl) & NIC_HALTED){
		printk("%s: Restarting nic\n", dev->name);
		memset(rrpriv->rx_ctrl, 0, 256 * sizeof(struct ring_ctrl));
		memset(rrpriv->info, 0, sizeof(struct rr_info));
		wmb();
		for (i = 0; i < TX_RING_ENTRIES; i++) {
			if (rrpriv->tx_skbuff[i]) {
				rrpriv->tx_ring[i].size = 0;
				set_rraddr(&rrpriv->tx_ring[i].addr, 0);
				dev_kfree_skb(rrpriv->tx_skbuff[i]);
				rrpriv->tx_skbuff[i] = NULL;
			}
		}

		for (i = 0; i < RX_RING_ENTRIES; i++) {
			if (rrpriv->rx_skbuff[i]) {
				rrpriv->rx_ring[i].size = 0;
				set_rraddr(&rrpriv->rx_ring[i].addr, 0);