patch-2.1.130 linux/drivers/net/acenic.c

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diff -u --recursive --new-file v2.1.129/linux/drivers/net/acenic.c linux/drivers/net/acenic.c
@@ -0,0 +1,1576 @@
+/*
+ * acenic.c: Linux driver for the Alteon AceNIC Gigabit Ethernet card
+ *           and other Tigon based cards.
+ *
+ * Copyright 1998 by Jes Sorensen, <Jes.Sorensen@cern.ch>.
+ *
+ * Thanks to Alteon and 3Com for providing hardware and documentation
+ * enabling me to write this driver.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#define DEBUG 1
+#define RX_DMA_SKBUFF 1
+#define PKT_COPY_THRESHOLD 300
+
+#include <linux/module.h>
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/ioport.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/mm.h>
+#include <net/sock.h>
+#include <net/ip.h>
+
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/byteorder.h>
+
+#include "acenic.h"
+
+/*
+ * These must be defined before the firmware is included.
+ */
+#define MAX_TEXT_LEN	96*1024
+#define MAX_RODATA_LEN	8*1024
+#define MAX_DATA_LEN	2*1024
+
+#include "acenic_firmware.h"
+
+
+/*
+ * This driver currently supports Tigon I and Tigon II based cards
+ * including the Alteon AceNIC and the 3Com 3C985.
+ *
+ * This card is really neat, it supports receive hardware checksumming
+ * and jumbo frames (up to 9000 bytes) and does a lot of work in the
+ * firmware. Also the programming interface is quite neat, except for
+ * the parts dealing with the i2c eeprom on the card ;-)
+ *
+ * A number of standard Ethernet receive skb's are now allocated at
+ * init time and not released before the driver is unloaded. This
+ * makes it possible to do ifconfig down/up.
+ *
+ * Using jumbo frames:
+ *
+ * To enable jumbo frames, simply specify an mtu between 1500 and 9000
+ * bytes to ifconfig. Jumbo frames can be enabled or disabled at any time
+ * by running `ifconfig eth<X> mtu <MTU>' with <X> being the Ethernet
+ * interface number and <MTU> being the MTU value.
+ *
+ * TODO:
+ *
+ * - Add multicast support.
+ * - Make all the tuning parameters and link speed negotiation, user
+ *   settable at driver/module init time.
+ */
+
+static const char *version = "acenic.c: v0.13 11/25/98  Jes Sorensen (Jes.Sorensen@cern.ch)\n";
+
+static struct device *root_dev = NULL;
+
+static int ace_load_firmware(struct device *dev);
+
+__initfunc(int acenic_probe (struct device *dev))
+{
+	static int i = 0;
+	int boards_found = 0;
+	int version_disp;
+	u32 tmp;
+	struct ace_private *ap;
+	u16 vendor, device;
+	u8 pci_bus;
+	u8 pci_dev_fun;
+	u8 pci_latency;
+	u8 irq;
+
+	if (!pci_present())		/* is PCI support present? */
+		return -ENODEV;
+
+	version_disp = 0;
+
+	for (; i < 255; i++)
+	{
+		dev = NULL;
+
+		if (pcibios_find_class(PCI_CLASS_NETWORK_ETHERNET << 8,
+				       i, &pci_bus, &pci_dev_fun) !=
+		    PCIBIOS_SUCCESSFUL)
+			break;
+
+		pcibios_read_config_word(pci_bus, pci_dev_fun,
+					 PCI_VENDOR_ID, &vendor);
+
+		pcibios_read_config_word(pci_bus, pci_dev_fun,
+					 PCI_DEVICE_ID, &device);
+
+		if ((vendor != PCI_VENDOR_ID_ALTEON) &&
+		    !((vendor == PCI_VENDOR_ID_3COM) &&
+		      (device == PCI_DEVICE_ID_3COM_3C985)))
+			continue;
+
+		dev = init_etherdev(dev, sizeof(struct ace_private));
+
+		if (dev == NULL){
+			printk(KERN_ERR "Unable to allocate etherdev "
+			       "structure!\n");
+			break;
+		}
+
+		if (!dev->priv)
+			dev->priv = kmalloc(sizeof(*ap), GFP_KERNEL);
+
+		ap = dev->priv;
+		ap->vendor = vendor;
+
+		/* Read register base address from
+		   PCI Configuration Space */
+
+		pcibios_read_config_dword(pci_bus, pci_dev_fun,
+					  PCI_BASE_ADDRESS_0, &tmp);
+
+		pcibios_read_config_byte(pci_bus, pci_dev_fun,
+					 PCI_INTERRUPT_LINE, &irq);
+
+		pcibios_read_config_word(pci_bus, pci_dev_fun,
+					 PCI_COMMAND, &ap->pci_command);
+
+		if (!(ap->pci_command & PCI_COMMAND_MASTER)){
+			ap->pci_command |= PCI_COMMAND_MASTER;
+			pcibios_write_config_word(pci_bus, pci_dev_fun,
+						  PCI_COMMAND,
+						  ap->pci_command);
+		}
+
+		if (!(ap->pci_command & PCI_COMMAND_MEMORY)){
+			printk(KERN_ERR "Shared mem not enabled - "
+			       "unable to configure AceNIC\n");
+			break;
+		}
+
+		dev->irq = irq;
+		ap->pci_bus = pci_bus;
+		ap->pci_dev_fun = pci_dev_fun;
+#ifdef __SMP__
+		spin_lock_init(&ap->lock);
+#endif
+
+		dev->open = &ace_open;
+		dev->hard_start_xmit = &ace_start_xmit;
+		dev->stop = &ace_close;
+		dev->get_stats = &ace_get_stats;
+		dev->set_multicast_list = &ace_set_multicast_list;
+		dev->set_mac_address = &ace_set_mac_addr;
+		dev->change_mtu = &ace_change_mtu;
+
+		/*
+		 * Dummy value.
+		 */
+		dev->base_addr = 42;
+
+		/* display version info if adapter is found */
+		if (!version_disp)
+		{
+			/* set display flag to TRUE so that */
+			/* we only display this string ONCE */
+			version_disp = 1;
+			printk(version);
+		}
+
+		pcibios_read_config_byte(pci_bus, pci_dev_fun,
+					 PCI_LATENCY_TIMER, &pci_latency);
+		if (pci_latency <= 0x40){
+			pci_latency = 0x40;
+			pcibios_write_config_byte(pci_bus, pci_dev_fun,
+						  PCI_LATENCY_TIMER,
+						  pci_latency);
+		}
+
+		switch(ap->vendor){
+		case PCI_VENDOR_ID_ALTEON:
+			sprintf(ap->name, "AceNIC Gigabit Ethernet");
+			printk(KERN_INFO "%s: Alteon AceNIC ", dev->name);
+			break;
+		case PCI_VENDOR_ID_3COM:
+			sprintf(ap->name, "3Com 3C985 Gigabit Ethernet");
+			printk(KERN_INFO "%s: 3Com 3C985 ", dev->name);
+			break;
+		default:
+			sprintf(ap->name, "Unknown AceNIC based Gigabit Ethernet");
+			printk(KERN_INFO "%s: Unknown AceNIC ", dev->name);
+			break;
+		}
+		printk("Gigabit Ethernet at 0x%08x, irq %i, PCI latency %i "
+		       "clks\n", tmp, dev->irq, pci_latency);
+
+		/*
+		 * Remap the regs into kernel space.
+		 */
+
+		ap->regs = (struct ace_regs *)ioremap(tmp, 0x4000);
+		if (!ap->regs){
+			printk(KERN_ERR "%s:  Unable to map I/O register, "
+			       "AceNIC %i will be disabled.\n", dev->name, i);
+			break;
+		}
+
+		ace_init(dev);
+
+		boards_found++;
+
+		/*
+		 * This is bollocks, but we need to tell the net-init
+		 * code that it shall go for the next device.
+		 */
+		dev->base_addr = 0;
+	}
+
+	/*
+	 * If we're at this point we're going through ace_probe() for
+	 * the first time.  Return success (0) if we've initialized 1
+	 * or more boards. Otherwise, return failure (-ENODEV).
+	 */
+
+#ifdef MODULE
+	return boards_found;
+#else
+	if (boards_found > 0)
+		return 0;
+	else
+		return -ENODEV;
+#endif
+}
+
+
+#ifdef MODULE
+int init_module(void)
+{
+	int cards;
+
+	root_dev = NULL;
+
+	cards = acenic_probe(NULL);
+	return cards ? 0 : -ENODEV;
+}
+
+void cleanup_module(void)
+{
+	struct ace_private *ap;
+	struct ace_regs *regs;
+	struct device *next;
+	short i;
+	unsigned long flags;
+
+	while (root_dev) {
+		next = ((struct ace_private *)root_dev->priv)->next;
+		ap = (struct ace_private *)root_dev->priv;
+
+		regs = ap->regs;
+		spin_lock_irqsave(&ap->lock, flags);
+
+		regs->CpuCtrl |= CPU_HALT;
+		if (ap->version == 2)
+			regs->CpuBCtrl |= CPU_HALT;
+		regs->Mb0Lo = 0;
+
+		spin_unlock_irqrestore(&ap->lock, flags);
+
+		/*
+		 * Release the RX buffers.
+		 */
+		for (i = 0; i < RX_STD_RING_ENTRIES; i++) {
+			if (ap->rx_std_skbuff[i]) {
+				ap->rx_std_ring[i].size = 0;
+				ap->rx_std_ring[i].addr = 0;
+				dev_kfree_skb(ap->rx_std_skbuff[i]);
+			}
+		}
+
+		iounmap(regs);
+		kfree(ap->info);
+		free_irq(root_dev->irq, root_dev);
+		unregister_netdev(root_dev);
+		kfree(root_dev);
+
+		root_dev = next;
+	}
+}
+#endif
+
+
+/*
+ * Commands are considered to be slow.
+ */
+static inline void ace_issue_cmd(struct ace_regs *regs, struct cmd *cmd)
+{
+	u32 idx;
+
+	idx = regs->CmdPrd;
+
+	regs->CmdRng[idx] = *(u32 *)(cmd);
+	idx = (idx + 1) % CMD_RING_ENTRIES;
+
+	regs->CmdPrd = idx;
+}
+
+
+__initfunc(static int ace_init(struct device *dev))
+{
+	struct ace_private *ap;
+	struct ace_regs *regs;
+	struct ace_info *info;
+	u32 tig_ver, mac1 = 0, mac2 = 0, tmp;
+	unsigned long tmp_ptr, myjif;
+	short i;
+
+	ap = dev->priv;
+	regs = ap->regs;
+
+#if 0
+	regs->HostCtrl  |= 0x08;
+	regs->CpuCtrl = CPU_RESET;
+	regs->CpuBCtrl = CPU_RESET;
+
+	{
+		long myjif = jiffies + HZ;
+		while (myjif > jiffies);
+	}
+#endif
+
+	/*
+	 * Don't access any other registes before this point!
+	 */
+#ifdef __BIG_ENDIAN
+	regs->HostCtrl = ((BYTE_SWAP | WORD_SWAP | CLR_INT) |
+			  ((BYTE_SWAP | WORD_SWAP | CLR_INT) << 24));
+#else
+	regs->HostCtrl = (CLR_INT | WORD_SWAP |
+			  ((CLR_INT | WORD_SWAP) << 24));
+#endif
+
+#ifdef __LITTLE_ENDIAN
+	regs->ModeStat = ACE_BYTE_SWAP_DATA | ACE_WARN | ACE_FATAL
+			| ACE_WORD_SWAP;
+#else
+#error "this driver doesn't run on big-endian machines yet!"
+#endif
+
+	/*
+	 * Stop the NIC CPU and clear pending interrupts
+	 */
+	regs->CpuCtrl |= CPU_HALT;
+	regs->Mb0Lo = 0;
+
+	tig_ver = regs->HostCtrl >> 28;
+
+	switch(tig_ver){
+	case 4:
+		printk(KERN_INFO"  Tigon I (Rev. 4), Firmware: %i.%i.%i, ",
+		       tigonFwReleaseMajor, tigonFwReleaseMinor,
+		       tigonFwReleaseFix);
+		regs->LocalCtrl = 0;
+		ap->version = 1;
+		break;
+	case 6:
+		printk(KERN_INFO"  Tigon II (Rev. %i), Firmware: %i.%i.%i, ",
+		       tig_ver, tigon2FwReleaseMajor, tigon2FwReleaseMinor,
+		       tigon2FwReleaseFix);
+		regs->CpuBCtrl |= CPU_HALT;
+		regs->LocalCtrl = SRAM_BANK_512K;
+		regs->MiscCfg = SYNC_SRAM_TIMING;
+		ap->version = 2;
+		break;
+	default:
+		printk(KERN_INFO"  Unsupported Tigon version detected (%i), ",
+		       tig_ver);
+		return -ENODEV;
+	}
+
+	for(i = 0; i < 4; i++){
+		mac1 = mac1 << 8;
+		mac1 |= read_eeprom_byte(regs, 0x8c+i);
+	}
+	for(i = 4; i < 8; i++){
+		mac2 = mac2 << 8;
+		mac2 |= read_eeprom_byte(regs, 0x8c+i);
+	}
+
+	regs->MacAddrHi = mac1;
+	regs->MacAddrLo = mac2;
+
+	printk("MAC: %02x:%02x:%02x:%02x:%02x:%02x\n",
+	       (mac1 >> 8) & 0xff, mac1 & 0xff, (mac2 >> 24) &0xff,
+	       (mac2 >> 16) & 0xff, (mac2 >> 8) & 0xff, mac2 & 0xff);
+
+	dev->dev_addr[0] = (mac1 >> 8) & 0xff;
+	dev->dev_addr[1] = mac1 & 0xff;
+	dev->dev_addr[2] = (mac2 >> 24) & 0xff;
+	dev->dev_addr[3] = (mac2 >> 16) & 0xff;
+	dev->dev_addr[4] = (mac2 >> 8) & 0xff;
+	dev->dev_addr[5] = mac2 & 0xff;
+
+	/*
+	 * Set the max DMA transfer size. Seems that for most systems
+	 * the performance is better when no MAX parameter is
+	 * set. However for systems enabling PCI write and invalidate,
+	 * DMA writes must be set to the L1 cache line size to get
+	 * optimal performance.
+	 */
+	tmp = READ_CMD_MEM | WRITE_CMD_MEM;
+	if (ap->version == 2){
+		tmp |= DMA_WRITE_ALL_ALIGN;
+		if (ap->pci_command & PCI_COMMAND_INVALIDATE){
+			switch(L1_CACHE_BYTES){
+			case 16:
+				tmp |= DMA_WRITE_MAX_16;
+				break;
+			case 32:
+				tmp |= DMA_WRITE_MAX_32;
+				break;
+			case 64:
+				tmp |= DMA_WRITE_MAX_64;
+				break;
+			default:
+				printk(KERN_INFO "  Cache line size %i not "
+				       "supported, PCI write and invalidate "
+				       "disabled\n", L1_CACHE_BYTES);
+				ap->pci_command &= ~PCI_COMMAND_INVALIDATE;
+				pcibios_write_config_word(ap->pci_bus,
+							  ap->pci_dev_fun,
+							  PCI_COMMAND,
+							  ap->pci_command);
+			}
+		}
+	}
+	regs->PciState = tmp;
+
+	if (request_irq(dev->irq, ace_interrupt, SA_SHIRQ, ap->name, dev))
+	{
+		printk(KERN_WARNING "%s: Requested IRQ %d is busy\n",
+		       dev->name, dev->irq);
+		return -EAGAIN;
+	}
+
+	/*
+	 * Initialize the generic info block and the command+event rings
+	 * and the control blocks for the transmit and receive rings
+	 * as they need to be setup once and for all.
+	 */
+	if (!(info = kmalloc(sizeof(struct ace_info), GFP_KERNEL | GFP_DMA))){
+		free_irq(dev->irq, dev);
+		return -EAGAIN;
+	}
+
+	ap->info = info;
+	memset(info, 0, sizeof(struct ace_info));
+
+	ace_load_firmware(dev);
+	ap->fw_running = 0;
+
+	tmp_ptr = virt_to_bus((void *)info);
+#if (BITS_PER_LONG == 64)
+	regs->InfoPtrHi = (tmp_ptr >> 32);
+#else
+	regs->InfoPtrHi = 0;
+#endif
+	regs->InfoPtrLo = ((tmp_ptr) & 0xffffffff);
+
+	memset(ap->evt_ring, 0, EVT_RING_ENTRIES * sizeof(struct event));
+
+	info->evt_ctrl.rngptr = virt_to_bus(ap->evt_ring);
+	info->evt_ctrl.flags = 0;
+
+	info->evt_prd_ptr = virt_to_bus(&ap->evt_prd);
+	ap->evt_prd = 0;
+	regs->EvtCsm = 0;
+
+	info->cmd_ctrl.flags = 0;
+	info->cmd_ctrl.rngptr = 0x100;
+	info->cmd_ctrl.max_len = 0;
+
+	for (i = 0; i < CMD_RING_ENTRIES; i++) {
+		regs->CmdRng[i] = 0;
+	}
+
+	regs->CmdPrd = 0;
+	regs->CmdCsm = 0;
+
+	info->stats2_ptr = virt_to_bus(&info->s.stats);
+
+	info->rx_std_ctrl.max_len = ACE_STD_MTU + ETH_HLEN + 4;
+	info->rx_std_ctrl.rngptr = virt_to_bus(ap->rx_std_ring);
+	info->rx_std_ctrl.flags = RX_TCP_UDP_SUM;
+
+	memset(ap->rx_std_ring, 0,
+	       RX_STD_RING_ENTRIES * sizeof(struct rx_desc));
+
+	info->rx_jumbo_ctrl.max_len = 0;
+	info->rx_jumbo_ctrl.rngptr = virt_to_bus(ap->rx_jumbo_ring);
+	info->rx_jumbo_ctrl.flags = RX_TCP_UDP_SUM;
+
+	memset(ap->rx_jumbo_ring, 0,
+	       RX_JUMBO_RING_ENTRIES * sizeof(struct rx_desc));
+
+	info->rx_return_ctrl.max_len = 0;
+	info->rx_return_ctrl.rngptr = virt_to_bus(ap->rx_return_ring);
+	info->rx_return_ctrl.flags = 0;
+
+	memset(ap->rx_return_ring, 0,
+	       RX_RETURN_RING_ENTRIES * sizeof(struct rx_desc));
+
+	info->rx_ret_prd_ptr = virt_to_bus(&ap->rx_ret_prd);
+
+	regs->WinBase = TX_RING_BASE;
+	ap->tx_ring = (struct tx_desc *)regs->Window;
+	memset(ap->tx_ring, 0, TX_RING_ENTRIES * sizeof(struct tx_desc));
+
+	info->tx_ctrl.max_len = TX_RING_ENTRIES;
+	info->tx_ctrl.flags = 0;
+#if (BITS_PER_LONG == 64) && defined(__BIG_ENDIAN)
+	info->tx_ctrl.rngptr = TX_RING_BASE << 32;
+#else
+	info->tx_ctrl.rngptr = TX_RING_BASE;
+#endif
+
+	info->tx_csm_ptr = virt_to_bus(&ap->tx_csm);
+
+	regs->DmaReadCfg = DMA_THRESH_8W;
+	regs->DmaWriteCfg = DMA_THRESH_8W;
+
+	regs->MaskInt = 0;
+	regs->IfIdx = 1;
+
+#if 0
+{
+	u32 tmp;
+	tmp = regs->AssistState;
+	tmp &= ~2;
+	tmp |= 1;
+	regs->AssistState = tmp;
+
+	tmp = regs->MacRxState;
+	tmp &= ~4;
+	regs->MacRxState = tmp;
+}
+#endif
+	regs->TuneStatTicks = 2 * TICKS_PER_SEC;
+	regs->TuneTxCoalTicks = TICKS_PER_SEC / 500;
+	regs->TuneMaxTxDesc = 7;
+	regs->TuneRxCoalTicks = TICKS_PER_SEC / 10000;
+	regs->TuneMaxRxDesc = 2;
+	regs->TuneTrace = 0 /* 0x30001fff */;
+	tmp = LNK_ENABLE | LNK_FULL_DUPLEX | LNK_1000MB |
+		LNK_RX_FLOW_CTL_Y | LNK_NEG_FCTL | LNK_NEGOTIATE;
+	if(ap->version == 1)
+		regs->TuneLink = tmp;
+	else{
+		tmp |= LNK_TX_FLOW_CTL_Y;
+		regs->TuneLink = tmp;
+		regs->TuneFastLink = tmp;
+	}
+
+	if (ap->version == 1)
+		regs->Pc = tigonFwStartAddr;
+	else if (ap->version == 2)
+		regs->Pc = tigon2FwStartAddr;
+
+	regs->Mb0Lo = 0;
+
+	/*
+	 * Start the NIC CPU
+	 */
+
+	regs->CpuCtrl = (regs->CpuCtrl & ~(CPU_HALT | CPU_TRACE));
+
+	/*
+	 * Wait for the firmware to spin up - max 2 seconds.
+	 */
+	myjif = jiffies + 3 * HZ;
+	while ((myjif > jiffies) && !ap->fw_running);
+	if (!ap->fw_running){
+		printk(KERN_ERR "%s: firmware NOT running!\n", dev->name);
+		return -EBUSY;
+	}
+
+	ap->next = root_dev;
+	root_dev = dev;
+
+	/*
+	 * We load the ring here as there seem to be no way to tell the
+	 * firmware to wipe the ring without re-initializing it.
+	 */
+	ace_load_std_rx_ring(dev);
+
+	return 0;
+}
+
+
+/*
+ * Monitor the card to detect hangs.
+ */
+
+static void ace_timer(unsigned long data)
+{
+	struct device *dev = (struct device *)data;
+	struct ace_private *ap = (struct ace_private *)dev->priv;
+	struct ace_regs *regs = ap->regs;
+
+	/*
+	 * We haven't received a stats update event for more than 2.5
+	 * seconds and there is data in the transmit queue, thus we
+	 * asume the card is stuck.
+	 */
+	if (ap->tx_csm != ap->tx_ret_csm){
+		printk(KERN_WARNING "%s: Transmitter is stuck, %08x\n",
+		       dev->name, regs->HostCtrl);
+	}
+
+	ap->timer.expires = jiffies + (5/2*HZ);
+	add_timer(&ap->timer);
+}
+
+
+/*
+ * Load the standard rx ring.
+ */
+static int ace_load_std_rx_ring(struct device *dev)
+{
+	struct ace_private *ap;
+	struct ace_regs *regs;
+	struct ace_info *info;
+	unsigned long flags;
+	struct cmd cmd;
+	short i;
+
+	ap = (struct ace_private *)dev->priv;
+	regs = ap->regs;
+	info = ap->info;
+
+	spin_lock_irqsave(&ap->lock, flags);
+
+	/*
+	 * Set tx_csm 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.
+	 */
+	ap->tx_full = 0;
+	ap->cur_rx = ap->dirty_rx = 0;
+	ap->tx_prd = ap->tx_csm = ap->tx_ret_csm = 0;
+	regs->RxRetCsm = 0;
+
+	for (i = 0; i < RX_RING_THRESH; i++) {
+		struct sk_buff *skb;
+
+		ap->rx_std_ring[i].flags = 0;
+		skb = alloc_skb(ACE_STD_MTU + ETH_HLEN + 6, GFP_ATOMIC);
+		ap->rx_std_skbuff[i] = skb;
+
+		/*
+		 * Make sure the data contents end up on an aligned address
+		 */
+		skb_reserve(skb, 2);
+
+		ap->rx_std_ring[i].addr = virt_to_bus(skb->data);
+		ap->rx_std_ring[i].size = ACE_STD_MTU + ETH_HLEN + 4;
+
+		ap->rx_std_ring[i].flags = 0;
+		ap->rx_std_ring[i].type = DESC_RX;
+
+		ap->rx_std_ring[i].idx = i;
+	}
+
+	ap->rx_std_skbprd = i;
+
+	/*
+	 * The last descriptor needs to be marked as being special.
+	 */
+	ap->rx_std_ring[i-1].type = DESC_END;
+
+	cmd.evt = C_SET_RX_PRD_IDX;
+	cmd.code = 0;
+	cmd.idx = ap->rx_std_skbprd;
+	ace_issue_cmd(regs, &cmd);
+
+	spin_unlock_irqrestore(&ap->lock, flags);
+
+	return 0;
+}
+
+
+/*
+ * Load the jumbo rx ring, this may happen at any time if the MTU
+ * is changed to a value > 1500.
+ */
+static int ace_load_jumbo_rx_ring(struct device *dev)
+{
+	struct ace_private *ap;
+	struct ace_regs *regs;
+	struct cmd cmd;
+	unsigned long flags;
+	short i;
+
+	ap = (struct ace_private *)dev->priv;
+	regs = ap->regs;
+
+	spin_lock_irqsave(&ap->lock, flags);
+
+	for (i = 0; i < RX_RING_THRESH; i++) {
+		struct sk_buff *skb;
+
+		ap->rx_jumbo_ring[i].flags = 0;
+		skb = alloc_skb(ACE_JUMBO_MTU + ETH_HLEN + 6, GFP_ATOMIC);
+		ap->rx_jumbo_skbuff[i] = skb;
+
+		/*
+		 * Make sure the data contents end up on an aligned address
+		 */
+		skb_reserve(skb, 2);
+
+		ap->rx_jumbo_ring[i].addr = virt_to_bus(skb->data);
+		ap->rx_jumbo_ring[i].size = ACE_JUMBO_MTU + ETH_HLEN + 4;
+
+		ap->rx_jumbo_ring[i].flags = JUMBO_FLAG;
+		ap->rx_jumbo_ring[i].type = DESC_RX;
+
+		ap->rx_jumbo_ring[i].idx = i;
+	}
+
+	ap->rx_jumbo_skbprd = i;
+
+	/*
+	 * The last descriptor needs to be marked as being special.
+	 */
+	ap->rx_jumbo_ring[i-1].type = DESC_END;
+
+	cmd.evt = C_SET_RX_JUMBO_PRD_IDX;
+	cmd.code = 0;
+	cmd.idx = ap->rx_jumbo_skbprd;
+	ace_issue_cmd(regs, &cmd);
+
+	spin_unlock_irqrestore(&ap->lock, flags);
+
+	return 0;
+}
+
+
+/*
+ * Tell the firmware not to accept jumbos and flush the jumbo ring.
+ * This function must be called with the spinlock held.
+ */
+static int ace_flush_jumbo_rx_ring(struct device *dev)
+{
+	struct ace_private *ap;
+	struct ace_regs *regs;
+	struct cmd cmd;
+	short i;
+
+	ap = (struct ace_private *)dev->priv;
+	regs = ap->regs;
+
+	if (ap->jumbo){
+		cmd.evt = C_RESET_JUMBO_RNG;
+		cmd.code = 0;
+		cmd.idx = 0;
+		ace_issue_cmd(regs, &cmd);
+
+		for (i = 0; i < RX_JUMBO_RING_ENTRIES; i++) {
+			if (ap->rx_jumbo_skbuff[i]) {
+				ap->rx_jumbo_ring[i].size = 0;
+				ap->rx_jumbo_ring[i].addr = 0;
+				dev_kfree_skb(ap->rx_jumbo_skbuff[i]);
+			}
+		}
+	}else
+		printk(KERN_ERR "%s: Trying to flush Jumbo ring without "
+		       "Jumbo support enabled\n", dev->name);
+
+	return 0;
+}
+
+
+/*
+ * 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 ace_handle_event(struct device *dev, u32 evtcsm, u32 evtprd)
+{
+	struct ace_private *ap;
+	struct ace_regs *regs;
+
+	ap = (struct ace_private *)dev->priv;
+	regs = ap->regs;
+
+	while (evtcsm != evtprd){
+		switch (ap->evt_ring[evtcsm].evt){
+		case E_FW_RUNNING:
+			printk(KERN_INFO "%s: Firmware up and running\n",
+			       dev->name);
+			ap->fw_running = 1;
+			break;
+		case E_STATS_UPDATED:
+			mod_timer(&ap->timer, jiffies + (5/2*HZ));
+			break;
+		case E_LNK_STATE:
+		{
+			u16 code = ap->evt_ring[evtcsm].code;
+			if (code == E_C_LINK_UP){
+				printk("%s: Optical link UP\n", dev->name);
+			}
+			else if (code == E_C_LINK_DOWN)
+				printk(KERN_INFO "%s: Optical link DOWN\n",
+				       dev->name);
+			else
+				printk(KERN_INFO "%s: Unknown optical link "
+				       "state %02x\n", dev->name, code);
+			break;
+		}
+		case E_ERROR:
+			switch(ap->evt_ring[evtcsm].code){
+			case E_C_ERR_INVAL_CMD:
+				printk(KERN_ERR "%s: invalid command error\n",
+				       dev->name);
+				break;
+			case E_C_ERR_UNIMP_CMD:
+				printk(KERN_ERR "%s: unimplemented command "
+				       "error\n", dev->name);
+				break;
+			case E_C_ERR_BAD_CFG:
+				printk(KERN_ERR "%s: bad config error\n",
+				       dev->name);
+				break;
+			default:
+				printk(KERN_ERR "%s: unknown error %02x\n",
+				       dev->name, ap->evt_ring[evtcsm].code);
+			}
+			break;
+		case E_RESET_JUMBO_RNG:
+			break;
+		default:
+			printk(KERN_ERR "%s: Unhandled event 0x%02x\n",
+			       dev->name, ap->evt_ring[evtcsm].evt);
+		}
+		evtcsm = (evtcsm + 1) % EVT_RING_ENTRIES;
+	}
+
+	return evtcsm;
+}
+
+
+static int rx_int(struct device *dev, u32 rxretprd, u32 rxretcsm)
+{
+	struct ace_private *ap = (struct ace_private *)dev->priv;
+	u32 idx, oldidx;
+	struct ace_regs *regs = ap->regs;
+
+	idx = rxretcsm;
+
+	while(idx != rxretprd){
+		struct sk_buff *skb, *newskb, *oldskb;
+		struct rx_desc *newrxdesc, *oldrxdesc;
+		u32 prdidx, size;
+		unsigned long addr;
+		u16 csum;
+		int jumbo;
+
+		oldidx = ap->rx_return_ring[idx].idx;
+		jumbo = ap->rx_return_ring[idx].flags & JUMBO_FLAG;
+
+		if (jumbo){
+			oldskb = ap->rx_jumbo_skbuff[oldidx];
+			prdidx = ap->rx_jumbo_skbprd;
+			newrxdesc = &ap->rx_jumbo_ring[prdidx];
+			oldrxdesc = &ap->rx_jumbo_ring[oldidx];
+		}else{
+			oldskb = ap->rx_std_skbuff[oldidx];
+			prdidx = ap->rx_std_skbprd;
+			newrxdesc = &ap->rx_std_ring[prdidx];
+			oldrxdesc = &ap->rx_std_ring[oldidx];
+		}
+
+		size = oldrxdesc->size;
+
+		if (size < PKT_COPY_THRESHOLD) {
+			skb = alloc_skb(size + 2, GFP_ATOMIC);
+			if (skb == NULL){
+				printk(KERN_ERR "%s: Out of memory\n",
+				       dev->name);
+				goto error;
+			}
+			/*
+			 * Make sure the real data is aligned
+			 */
+
+			skb_reserve(skb, 2);
+			memcpy(skb_put(skb, size), oldskb->data, size);
+			addr = oldrxdesc->addr;
+			newskb = oldskb;
+		}else{
+			skb = oldskb;
+
+			skb_put(skb, size);
+
+			newskb = alloc_skb(size + 2, GFP_ATOMIC);
+			if (newskb == NULL){
+				printk(KERN_ERR "%s: Out of memory\n",
+				       dev->name);
+				goto error;
+			}
+
+			/*
+			 * Make sure we DMA directly into nicely
+			 * aligned receive buffers
+			 */
+			skb_reserve(newskb, 2);
+			addr = virt_to_bus(newskb->data);
+		}
+
+		newrxdesc->addr = addr;
+		newrxdesc->size = size;
+
+		newrxdesc->flags = oldrxdesc->flags;
+		newrxdesc->idx = prdidx;
+		newrxdesc->type = DESC_RX;
+#if (BITS_PER_LONG == 32)
+		newrxdesc->zero = 0;
+#endif
+
+		oldrxdesc->size = 0;
+		oldrxdesc->addr = 0;
+
+		if (jumbo){
+			ap->rx_jumbo_skbuff[oldidx] = NULL;
+			ap->rx_jumbo_skbuff[prdidx] = newskb;
+
+			prdidx = (prdidx + 1) % RX_JUMBO_RING_ENTRIES;
+			ap->rx_jumbo_skbprd = prdidx;
+		}else{
+			ap->rx_std_skbuff[oldidx] = NULL;
+			ap->rx_std_skbuff[prdidx] = newskb;
+
+			prdidx = (prdidx + 1) % RX_STD_RING_ENTRIES;
+			ap->rx_std_skbprd = prdidx;
+		}
+
+		/*
+		 * Fly baby, fly!
+		 */
+		csum = ap->rx_return_ring[idx].tcp_udp_csum;
+
+		skb->dev = dev;
+		skb->protocol = eth_type_trans(skb, dev);
+
+		/*
+		 * If the checksum is correct and this is not a
+		 * fragment, tell the stack that the data is correct.
+		 */
+		if(!(csum ^ 0xffff) &&
+		   (!(((struct iphdr *)skb->data)->frag_off &
+		      __constant_htons(IP_MF|IP_OFFSET))))
+			skb->ip_summed = CHECKSUM_UNNECESSARY;
+		else
+			skb->ip_summed = CHECKSUM_NONE;
+
+		netif_rx(skb);		/* send it up */
+
+		ap->stats.rx_packets++;
+		ap->stats.rx_bytes += skb->len;
+
+		if ((prdidx & 0x7) == 0){
+			struct cmd cmd;
+			if (jumbo)
+				cmd.evt = C_SET_RX_JUMBO_PRD_IDX;
+			else
+				cmd.evt = C_SET_RX_PRD_IDX;
+			cmd.code = 0;
+			cmd.idx = prdidx;
+			ace_issue_cmd(regs, &cmd);
+		}
+
+		idx = (idx + 1) % RX_RETURN_RING_ENTRIES;
+	}
+ out:
+	regs->RxRetCsm = idx;
+	ap->cur_rx = idx;
+
+	return idx;
+ error:
+	idx = rxretprd;
+	goto out;
+}
+
+
+static void ace_interrupt(int irq, void *dev_id, struct pt_regs *ptregs)
+{
+	struct ace_private *ap;
+	struct ace_regs *regs;
+	struct device *dev = (struct device *)dev_id;
+	u32 txcsm, rxretcsm, rxretprd;
+	u32 evtcsm, evtprd;
+
+	ap = (struct ace_private *)dev->priv;
+	regs = ap->regs;
+
+	spin_lock(&ap->lock);
+
+	/*
+	 * In case of PCI shared interrupts or spurious interrupts,
+	 * we want to make sure it is actually our interrupt before
+	 * spending any time in here.
+	 */
+	if (!(regs->HostCtrl & IN_INT)){
+		spin_unlock(&ap->lock);
+		return;
+	}
+
+#if 0
+	/*
+	 * Since we are also using a spinlock, I wonder if this is
+	 * actually worth it.
+	 */
+	if (test_and_set_bit(0, (void*)&dev->interrupt) != 0) {
+		printk(KERN_WARNING "%s: Re-entering the interrupt handler.\n",
+		       dev->name);
+		return;
+	}
+#endif
+
+	/*
+	 * Tell the card not to generate interrupts while we are in here.
+	 */
+	regs->Mb0Lo = 1;
+
+	txcsm = ap->tx_csm;
+	if (txcsm != ap->tx_ret_csm) {
+		u32 idx = ap->tx_ret_csm;
+
+		do {
+			ap->stats.tx_packets++;
+			ap->stats.tx_bytes += ap->tx_skbuff[idx]->len;
+			dev_kfree_skb(ap->tx_skbuff[idx]);
+
+			ap->tx_skbuff[idx] = NULL;
+
+			ap->tx_ring[idx].size = 0;
+			ap->tx_ring[idx].addr = 0;
+			ap->tx_ring[idx].flags = 0;
+
+			idx = (idx + 1) % TX_RING_ENTRIES;
+		} while (idx != txcsm);
+
+		if (ap->tx_full && dev->tbusy &&
+		    (((ap->tx_prd + 1) % TX_RING_ENTRIES) != txcsm)){
+			ap->tx_full = 0;
+			dev->tbusy = 0;
+			mark_bh(NET_BH);
+		}
+
+		ap->tx_ret_csm = txcsm;
+	}
+
+	rxretprd = ap->rx_ret_prd;
+	rxretcsm = ap->cur_rx;
+
+	if (rxretprd != rxretcsm)
+		rxretprd = rx_int(dev, rxretprd, rxretcsm);
+
+	evtcsm = regs->EvtCsm;
+	evtprd = ap->evt_prd;
+
+	if (evtcsm != evtprd){
+		evtcsm = ace_handle_event(dev, evtcsm, evtprd);
+	}
+
+	regs->EvtCsm = evtcsm;
+	regs->Mb0Lo = 0;
+
+	spin_unlock(&ap->lock);
+#if 0
+	dev->interrupt = 0;
+#endif
+}
+
+
+static int ace_open(struct device *dev)
+{
+	struct ace_private *ap;
+	struct ace_regs *regs;
+	struct cmd cmd;
+
+	ap = dev->priv;
+	regs = ap->regs;
+
+	if (!(ap->fw_running)){
+		printk(KERN_WARNING "%s: firmware not running!\n", dev->name);
+		return -EBUSY;
+	}
+
+	regs->IfMtu = dev->mtu + ETH_HLEN + 4;
+
+	cmd.evt = C_HOST_STATE;
+	cmd.code = C_C_STACK_UP;
+	cmd.idx = 0;
+	ace_issue_cmd(regs, &cmd);
+
+	if (ap->jumbo)
+		ace_load_jumbo_rx_ring(dev);
+
+	if (dev->flags & IFF_PROMISC){
+		cmd.evt = C_SET_PROMISC_MODE;
+		cmd.code = C_C_PROMISC_ENABLE;
+		cmd.idx = 0;
+		ace_issue_cmd(regs, &cmd);
+
+		ap->promisc = 1;
+	}else
+		ap->promisc = 0;
+
+#if 0
+	{ long myjif = jiffies + HZ;
+	while (jiffies < myjif);
+	}
+
+	cmd.evt = C_LNK_NEGOTIATION;
+	cmd.code = 0;
+	cmd.idx = 0;
+	ace_issue_cmd(regs, &cmd);
+#endif
+
+	dev->tbusy = 0;
+	dev->interrupt = 0;
+	dev->start = 1;
+
+	MOD_INC_USE_COUNT;
+
+	/*
+	 * Setup the timer
+	 */
+	init_timer(&ap->timer);
+	ap->timer.expires = jiffies + 5/2 * HZ;
+	ap->timer.data = (unsigned long)dev;
+	ap->timer.function = &ace_timer;
+	add_timer(&ap->timer);
+	return 0;
+}
+
+
+static int ace_close(struct device *dev)
+{
+	struct ace_private *ap;
+	struct ace_regs *regs;
+	struct cmd cmd;
+	unsigned long flags;
+	short i;
+
+	dev->start = 0;
+	set_bit(0, (void*)&dev->tbusy);
+
+	ap = (struct ace_private *)dev->priv;
+	regs = ap->regs;
+
+	del_timer(&ap->timer);
+
+	if (ap->promisc){
+		cmd.evt = C_SET_PROMISC_MODE;
+		cmd.code = C_C_PROMISC_DISABLE;
+		cmd.idx = 0;
+		ace_issue_cmd(regs, &cmd);
+		ap->promisc = 0;
+	}
+
+	cmd.evt = C_HOST_STATE;
+	cmd.code = C_C_STACK_DOWN;
+	cmd.idx = 0;
+	ace_issue_cmd(regs, &cmd);
+
+	spin_lock_irqsave(&ap->lock, flags);
+
+	for (i = 0; i < TX_RING_ENTRIES; i++) {
+		if (ap->tx_skbuff[i]) {
+			ap->tx_ring[i].size = 0;
+			ap->tx_ring[i].addr = 0;
+			dev_kfree_skb(ap->tx_skbuff[i]);
+		}
+	}
+
+	if (ap->jumbo)
+		ace_flush_jumbo_rx_ring(dev);
+
+	spin_unlock_irqrestore(&ap->lock, flags);
+
+	MOD_DEC_USE_COUNT;
+	return 0;
+}
+
+
+static int ace_start_xmit(struct sk_buff *skb, struct device *dev)
+{
+	struct ace_private *ap = (struct ace_private *)dev->priv;
+	struct ace_regs *regs = ap->regs;
+	unsigned long flags;
+	u32 idx;
+
+	spin_lock_irqsave(&ap->lock, flags);
+
+	idx = ap->tx_prd;
+
+	ap->tx_skbuff[idx] = skb;
+	ap->tx_ring[idx].addr = virt_to_bus(skb->data);
+	ap->tx_ring[idx].size = skb->len;
+	ap->tx_ring[idx].flags = DESC_END;
+	idx = (idx + 1) % TX_RING_ENTRIES;
+
+	ap->tx_prd = idx;
+	regs->TxPrd = idx;
+
+	if ((idx + 1) % TX_RING_ENTRIES == ap->tx_ret_csm){
+		ap->tx_full = 1;
+		set_bit(0, (void*)&dev->tbusy);
+	}
+
+	spin_unlock_irqrestore(&ap->lock, flags);
+
+	dev->trans_start = jiffies;
+	return 0;
+}
+
+
+static int ace_change_mtu(struct device *dev, int new_mtu)
+{
+	struct ace_private *ap = dev->priv;
+	struct ace_regs *regs = ap->regs;
+
+	if ((new_mtu < 68) || (new_mtu > ACE_JUMBO_MTU))
+		return -EINVAL;
+
+	regs->IfMtu = new_mtu + ETH_HLEN + 4;
+	dev->mtu = new_mtu;
+
+	if (new_mtu > ACE_STD_MTU){
+		if (!(ap->jumbo)){
+			printk(KERN_INFO "%s: Enabling Jumbo frame "
+			       "support\n", dev->name);
+			ap->jumbo = 1;
+			ace_load_jumbo_rx_ring(dev);
+		}
+		ap->jumbo = 1;
+	}else{
+		if (ap->jumbo){
+			ace_flush_jumbo_rx_ring(dev);
+
+			printk(KERN_INFO "%s: Disabling Jumbo frame support\n",
+			       dev->name);
+		}
+		ap->jumbo = 0;
+	}
+
+	return 0;
+}
+
+
+/*
+ * Set the hardware MAC address.
+ */
+static int ace_set_mac_addr(struct device *dev, void *p)
+{
+	struct sockaddr *addr=p;
+	struct ace_regs *regs;
+	u16 *da;
+	struct cmd cmd;
+
+	if(dev->start)
+		return -EBUSY;
+	memcpy(dev->dev_addr, addr->sa_data,dev->addr_len);
+
+	da = (u16 *)dev->dev_addr;
+
+	regs = ((struct ace_private *)dev->priv)->regs;
+	regs->MacAddrHi = da[0];
+	regs->MacAddrLo = (da[1] << 16) | da[2];
+
+	cmd.evt = C_SET_MAC_ADDR;
+	cmd.code = 0;
+	cmd.idx = 0;
+	ace_issue_cmd(regs, &cmd);
+
+	return 0;
+}
+
+
+static void ace_set_multicast_list(struct device *dev)
+{
+	struct ace_private *ap = dev->priv;
+	struct ace_regs *regs = ap->regs;
+	struct cmd cmd;
+
+	if ((dev->flags & IFF_PROMISC) && !(ap->promisc)) {
+		cmd.evt = C_SET_PROMISC_MODE;
+		cmd.code = C_C_PROMISC_ENABLE;
+		cmd.idx = 0;
+		ace_issue_cmd(regs, &cmd);
+
+		ap->promisc = 1;
+	}else if (!(dev->flags & IFF_PROMISC) && (ap->promisc)){
+		cmd.evt = C_SET_PROMISC_MODE;
+		cmd.code = C_C_PROMISC_DISABLE;
+		cmd.idx = 0;
+		ace_issue_cmd(regs, &cmd);
+
+		ap->promisc = 0;
+	}
+}
+
+
+static struct net_device_stats *ace_get_stats(struct device *dev)
+{
+	struct ace_private *ap = dev->priv;
+
+	return(&ap->stats);
+}
+
+
+__initfunc(int ace_copy(struct ace_regs *regs, void *src, u32 dest, int size))
+{
+	int tsize;
+	u32 tdest;
+
+	while(size > 0){
+		tsize = min(((~dest & (ACE_WINDOW_SIZE - 1)) + 1),
+			    min(size, ACE_WINDOW_SIZE));
+		tdest = dest & (ACE_WINDOW_SIZE - 1);
+		regs->WinBase = dest & ~(ACE_WINDOW_SIZE - 1);
+#ifdef __BIG_ENDIAN
+#error "data must be swapped here"
+#else
+#if 0
+		printk("copying %04x from %08x to %06x (Window addr %08x), winbase %02x\n", tsize, (unsigned)src, dest, (unsigned) ((void *)regs->Window + tdest), regs->WinBase);
+#endif
+		memcpy((void *)((void *)regs->Window + tdest), src, tsize);
+#endif
+		dest += tsize;
+		src += tsize;
+		size -= tsize;
+	}
+
+	return 0;
+}
+
+
+__initfunc(int ace_clear(struct ace_regs *regs, u32 dest, int size))
+{
+	int tsize;
+	u32 tdest;
+
+	while(size > 0){
+		tsize = min(((~dest & (ACE_WINDOW_SIZE - 1)) + 1),
+			    min(size, ACE_WINDOW_SIZE));
+		tdest = dest & (ACE_WINDOW_SIZE - 1);
+		regs->WinBase = dest & ~(ACE_WINDOW_SIZE - 1);
+
+		memset((void *)((void *)regs->Window + tdest), 0, tsize);
+
+		dest += tsize;
+		size -= tsize;
+	}
+
+	return 0;
+}
+
+
+/*
+ * Download the firmware into the SRAM on the NIC
+ *
+ * This operation requires the NIC to be halted and is performed with
+ * interrupts disabled and with the spinlock hold.
+ */
+__initfunc(int ace_load_firmware(struct device *dev))
+{
+	struct ace_private *ap;
+	struct ace_regs *regs;
+
+	ap = (struct ace_private *)dev->priv;
+	regs = ap->regs;
+
+	if (!(regs->CpuCtrl & CPU_HALTED)){
+		printk(KERN_ERR "%s: trying to download firmware while the "
+		       "CPU is running!\n", dev->name);
+		return -EFAULT;
+	}
+
+	ace_clear(regs, 0x2000, 0x100000-0x2000);
+	if (ap->version == 1){
+		ace_copy(regs, tigonFwText, tigonFwTextAddr, tigonFwTextLen);
+		ace_copy(regs, tigonFwData, tigonFwDataAddr, tigonFwDataLen);
+		ace_copy(regs, tigonFwRodata, tigonFwRodataAddr,
+			 tigonFwRodataLen);
+		ace_clear(regs, tigonFwBssAddr, tigonFwBssLen);
+		ace_clear(regs, tigonFwSbssAddr, tigonFwSbssLen);
+	}else if (ap->version == 2){
+		ace_clear(regs, tigon2FwBssAddr, tigon2FwBssLen);
+		ace_clear(regs, tigon2FwSbssAddr, tigon2FwSbssLen);
+		ace_copy(regs, tigon2FwText, tigon2FwTextAddr,tigon2FwTextLen);
+		ace_copy(regs, tigon2FwRodata, tigon2FwRodataAddr,
+			 tigon2FwRodataLen);
+		ace_copy(regs, tigon2FwData, tigon2FwDataAddr,tigon2FwDataLen);
+	}
+
+	return 0;
+}
+
+
+/*
+ * The eeprom on the AceNIC is an Atmel i2c EEPROM.
+ *
+ * Accessing the EEPROM is `interesting' to say the least - don't read
+ * this code right after dinner.
+ *
+ * This is all about black magic and bit-banging the device .... I
+ * wonder in what hospital they have put the guy who designed the i2c
+ * specs.
+ *
+ * Oh yes, this is only the beginning!
+ */
+static void eeprom_start(struct ace_regs *regs)
+{
+	udelay(1);
+	regs->LocalCtrl |= (EEPROM_DATA_OUT | EEPROM_WRITE_ENABLE);
+	udelay(1);
+	regs->LocalCtrl |= EEPROM_CLK_OUT;
+	udelay(1);
+	regs->LocalCtrl &= ~EEPROM_DATA_OUT;
+	udelay(1);
+	regs->LocalCtrl &= ~EEPROM_CLK_OUT;
+}
+
+
+static void eeprom_prep(struct ace_regs *regs, u8 magic)
+{
+	short i;
+
+	udelay(2);
+	regs->LocalCtrl &= ~EEPROM_DATA_OUT;
+	regs->LocalCtrl |= EEPROM_WRITE_ENABLE;
+
+	for (i = 0; i < 8; i++, magic <<= 1) {
+		udelay(2);
+		if (magic & 0x80) 
+			regs->LocalCtrl |= EEPROM_DATA_OUT;
+		else
+			regs->LocalCtrl &= ~EEPROM_DATA_OUT;
+
+		udelay(1);
+		regs->LocalCtrl |= EEPROM_CLK_OUT;
+		udelay(1);
+		regs->LocalCtrl &= ~(EEPROM_CLK_OUT | EEPROM_DATA_OUT);
+	}
+}
+
+
+static int eeprom_check_ack(struct ace_regs *regs)
+{
+	int state;
+    
+	regs->LocalCtrl &= ~EEPROM_WRITE_ENABLE;
+	udelay(2);
+	regs->LocalCtrl |= EEPROM_CLK_OUT;
+	udelay(1);
+	/* sample data in middle of high clk */
+	state = (regs->LocalCtrl & EEPROM_DATA_IN) != 0;
+	udelay(1);
+	regs->LocalCtrl &= ~EEPROM_CLK_OUT;
+
+	return state;
+}
+
+
+static void eeprom_stop(struct ace_regs *regs)
+{
+	regs->LocalCtrl |= EEPROM_WRITE_ENABLE;
+	udelay(1);
+	regs->LocalCtrl &= ~EEPROM_DATA_OUT;
+	udelay(1);
+	regs->LocalCtrl |= EEPROM_CLK_OUT;
+	udelay(1);
+	regs->LocalCtrl |= EEPROM_DATA_OUT;
+	udelay(2);
+	regs->LocalCtrl &= ~EEPROM_CLK_OUT;
+}
+
+
+/*
+ * Read a whole byte from the EEPROM.
+ */
+static u8 read_eeprom_byte(struct ace_regs *regs, unsigned long offset)
+{
+	u32 i;
+	u8 result = 0;
+
+	if (!regs){
+		printk(KERN_ERR "No regs!\n");
+		return 0;
+	}
+
+	eeprom_start(regs);
+
+	eeprom_prep(regs, EEPROM_WRITE_SELECT);
+	if (eeprom_check_ack(regs)){
+		printk("Unable to sync eeprom\n");
+		return 0;
+	}
+
+	eeprom_prep(regs, (offset >> 8) & 0xff);
+	if (eeprom_check_ack(regs))
+		return 0;
+
+	eeprom_prep(regs, offset & 0xff);
+	if (eeprom_check_ack(regs))
+		return 0;
+
+	eeprom_start(regs);
+	eeprom_prep(regs, EEPROM_READ_SELECT);
+	if (eeprom_check_ack(regs))
+		return 0;
+
+	for (i = 0; i < 8; i++) {
+		regs->LocalCtrl &= ~EEPROM_WRITE_ENABLE;
+		udelay(2);
+		regs->LocalCtrl |= EEPROM_CLK_OUT;
+		udelay(1);
+		/* sample data mid high clk */
+		result = (result << 1) |
+			((regs->LocalCtrl & EEPROM_DATA_IN) != 0);
+		udelay(1);
+		regs->LocalCtrl &= ~EEPROM_CLK_OUT;
+		if (i == 7)
+			regs->LocalCtrl |= EEPROM_WRITE_ENABLE;
+	}
+
+	regs->LocalCtrl |= EEPROM_DATA_OUT;
+	udelay(1);
+	regs->LocalCtrl |= EEPROM_CLK_OUT;
+	udelay(2);
+	regs->LocalCtrl &= ~EEPROM_CLK_OUT;
+	eeprom_stop(regs);
+
+	return result;
+}
+
+
+/*
+ * Local variables:
+ * compile-command: "gcc -D__KERNEL__ -D__SMP__ -I/data/home/jes/linux/include -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer -pipe -fno-strength-reduce -m486 -malign-loops=2 -malign-jumps=2 -malign-functions=2 -DCPU=686 -DMODULE -DMODVERSIONS -include /data/home/jes/linux/include/linux/modversions.h   -c -o acenic.o acenic.c"
+ * End:
+ */

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TCL-scripts by Sam Shen, slshen@lbl.gov