diff options
Diffstat (limited to 'i386/i386at/gpl/linux/net/3c501.c')
-rw-r--r-- | i386/i386at/gpl/linux/net/3c501.c | 860 |
1 files changed, 860 insertions, 0 deletions
diff --git a/i386/i386at/gpl/linux/net/3c501.c b/i386/i386at/gpl/linux/net/3c501.c new file mode 100644 index 00000000..6f8dceb6 --- /dev/null +++ b/i386/i386at/gpl/linux/net/3c501.c @@ -0,0 +1,860 @@ +/* 3c501.c: A 3Com 3c501 ethernet driver for linux. */ +/* + Written 1992,1993,1994 Donald Becker + + Copyright 1993 United States Government as represented by the + Director, National Security Agency. This software may be used and + distributed according to the terms of the GNU Public License, + incorporated herein by reference. + + This is a device driver for the 3Com Etherlink 3c501. + Do not purchase this card, even as a joke. It's performance is horrible, + and it breaks in many ways. + + The author may be reached as becker@CESDIS.gsfc.nasa.gov, or C/O + Center of Excellence in Space Data and Information Sciences + Code 930.5, Goddard Space Flight Center, Greenbelt MD 20771 + + Fixed (again!) the missing interrupt locking on TX/RX shifting. + Alan Cox <Alan.Cox@linux.org> + + Removed calls to init_etherdev since they are no longer needed, and + cleaned up modularization just a bit. The driver still allows only + the default address for cards when loaded as a module, but that's + really less braindead than anyone using a 3c501 board. :) + 19950208 (invid@msen.com) + + Added traps for interrupts hitting the window as we clear and TX load + the board. Now getting 150K/second FTP with a 3c501 card. Still playing + with a TX-TX optimisation to see if we can touch 180-200K/second as seems + theoretically maximum. + 19950402 Alan Cox <Alan.Cox@linux.org> + + Some notes on this thing if you have to hack it. [Alan] + + 1] Some documentation is available from 3Com. Due to the boards age + standard responses when you ask for this will range from 'be serious' + to 'give it to a museum'. The documentation is incomplete and mostly + of historical interest anyway. + + 2] The basic system is a single buffer which can be used to receive or + transmit a packet. A third command mode exists when you are setting + things up. + + 3] If it's transmitting it's not receiving and vice versa. In fact the + time to get the board back into useful state after an operation is + quite large. + + 4] The driver works by keeping the board in receive mode waiting for a + packet to arrive. When one arrives it is copied out of the buffer + and delivered to the kernel. The card is reloaded and off we go. + + 5] When transmitting dev->tbusy is set and the card is reset (from + receive mode) [possibly losing a packet just received] to command + mode. A packet is loaded and transmit mode triggered. The interrupt + handler runs different code for transmit interrupts and can handle + returning to receive mode or retransmissions (yes you have to help + out with those too). + + Problems: + There are a wide variety of undocumented error returns from the card + and you basically have to kick the board and pray if they turn up. Most + only occur under extreme load or if you do something the board doesn't + like (eg touching a register at the wrong time). + + The driver is less efficient than it could be. It switches through + receive mode even if more transmits are queued. If this worries you buy + a real ethernet card. + + The combination of slow receive restart and no real multicast + filter makes the board unusable with a kernel compiled for IP + multicasting in a real multicast environment. Thats down to the board, + but even with no multicast programs running a multicast IP kernel is + in group 224.0.0.1 and you will therefore be listening to all multicasts. + One nv conference running over that ethernet and you can give up. + +*/ + +static const char *version = + "3c501.c: 9/23/94 Donald Becker (becker@cesdis.gsfc.nasa.gov).\n"; + +/* + * Braindamage remaining: + * The 3c501 board. + */ + +#include <linux/module.h> + +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/ptrace.h> +#include <linux/fcntl.h> +#include <linux/ioport.h> +#include <linux/interrupt.h> +#include <linux/malloc.h> +#include <linux/string.h> +#include <linux/ioport.h> +#include <linux/errno.h> +#include <linux/config.h> /* for CONFIG_IP_MULTICAST */ + +#include <asm/bitops.h> +#include <asm/io.h> + +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/skbuff.h> + +#define BLOCKOUT_2 + +/* A zero-terminated list of I/O addresses to be probed. + The 3c501 can be at many locations, but here are the popular ones. */ +static unsigned int netcard_portlist[] = + { 0x280, 0x300, 0}; + + +/* + * Index to functions. + */ + +int el1_probe(struct device *dev); +static int el1_probe1(struct device *dev, int ioaddr); +static int el_open(struct device *dev); +static int el_start_xmit(struct sk_buff *skb, struct device *dev); +static void el_interrupt(int irq, struct pt_regs *regs); +static void el_receive(struct device *dev); +static void el_reset(struct device *dev); +static int el1_close(struct device *dev); +static struct enet_statistics *el1_get_stats(struct device *dev); +static void set_multicast_list(struct device *dev); + +#define EL1_IO_EXTENT 16 + +#ifndef EL_DEBUG +#define EL_DEBUG 0 /* use 0 for production, 1 for devel., >2 for debug */ +#endif /* Anything above 5 is wordy death! */ +static int el_debug = EL_DEBUG; + +/* + * Board-specific info in dev->priv. + */ + +struct net_local +{ + struct enet_statistics stats; + int tx_pkt_start; /* The length of the current Tx packet. */ + int collisions; /* Tx collisions this packet */ + int loading; /* Spot buffer load collisions */ +}; + + +#define RX_STATUS (ioaddr + 0x06) +#define RX_CMD RX_STATUS +#define TX_STATUS (ioaddr + 0x07) +#define TX_CMD TX_STATUS +#define GP_LOW (ioaddr + 0x08) +#define GP_HIGH (ioaddr + 0x09) +#define RX_BUF_CLR (ioaddr + 0x0A) +#define RX_LOW (ioaddr + 0x0A) +#define RX_HIGH (ioaddr + 0x0B) +#define SAPROM (ioaddr + 0x0C) +#define AX_STATUS (ioaddr + 0x0E) +#define AX_CMD AX_STATUS +#define DATAPORT (ioaddr + 0x0F) +#define TX_RDY 0x08 /* In TX_STATUS */ + +#define EL1_DATAPTR 0x08 +#define EL1_RXPTR 0x0A +#define EL1_SAPROM 0x0C +#define EL1_DATAPORT 0x0f + +/* + * Writes to the ax command register. + */ + +#define AX_OFF 0x00 /* Irq off, buffer access on */ +#define AX_SYS 0x40 /* Load the buffer */ +#define AX_XMIT 0x44 /* Transmit a packet */ +#define AX_RX 0x48 /* Receive a packet */ +#define AX_LOOP 0x0C /* Loopback mode */ +#define AX_RESET 0x80 + +/* + * Normal receive mode written to RX_STATUS. We must intr on short packets + * to avoid bogus rx lockups. + */ + +#define RX_NORM 0xA8 /* 0x68 == all addrs, 0xA8 only to me. */ +#define RX_PROM 0x68 /* Senior Prom, uhmm promiscuous mode. */ +#define RX_MULT 0xE8 /* Accept multicast packets. */ +#define TX_NORM 0x0A /* Interrupt on everything that might hang the chip */ + +/* + * TX_STATUS register. + */ + +#define TX_COLLISION 0x02 +#define TX_16COLLISIONS 0x04 +#define TX_READY 0x08 + +#define RX_RUNT 0x08 +#define RX_MISSED 0x01 /* Missed a packet due to 3c501 braindamage. */ +#define RX_GOOD 0x30 /* Good packet 0x20, or simple overflow 0x10. */ + + +/* + * The boilerplate probe code. + */ + +#ifdef HAVE_DEVLIST +struct netdev_entry el1_drv = {"3c501", el1_probe1, EL1_IO_EXTENT, netcard_portlist}; +#else + +int el1_probe(struct device *dev) +{ + int i; + int base_addr = dev ? dev->base_addr : 0; + + if (base_addr > 0x1ff) /* Check a single specified location. */ + return el1_probe1(dev, base_addr); + else if (base_addr != 0) /* Don't probe at all. */ + return ENXIO; + + for (i = 0; netcard_portlist[i]; i++) + { + int ioaddr = netcard_portlist[i]; + if (check_region(ioaddr, EL1_IO_EXTENT)) + continue; + if (el1_probe1(dev, ioaddr) == 0) + return 0; + } + + return ENODEV; +} +#endif + +/* + * The actual probe. + */ + +static int el1_probe1(struct device *dev, int ioaddr) +{ +#ifndef MODULE + + const char *mname; /* Vendor name */ + unsigned char station_addr[6]; + int autoirq = 0; + int i; + + /* + * Read the station address PROM data from the special port. + */ + + for (i = 0; i < 6; i++) + { + outw(i, ioaddr + EL1_DATAPTR); + station_addr[i] = inb(ioaddr + EL1_SAPROM); + } + /* + * Check the first three octets of the S.A. for 3Com's prefix, or + * for the Sager NP943 prefix. + */ + + if (station_addr[0] == 0x02 && station_addr[1] == 0x60 + && station_addr[2] == 0x8c) + { + mname = "3c501"; + } else if (station_addr[0] == 0x00 && station_addr[1] == 0x80 + && station_addr[2] == 0xC8) + { + mname = "NP943"; + } + else + return ENODEV; + + /* + * Grab the region so we can find the another board if autoIRQ fails. + */ + + request_region(ioaddr, EL1_IO_EXTENT,"3c501"); + + /* + * We auto-IRQ by shutting off the interrupt line and letting it float + * high. + */ + + if (dev->irq < 2) + { + autoirq_setup(2); + inb(RX_STATUS); /* Clear pending interrupts. */ + inb(TX_STATUS); + outb(AX_LOOP + 1, AX_CMD); + + outb(0x00, AX_CMD); + + autoirq = autoirq_report(1); + + if (autoirq == 0) + { + printk("%s probe at %#x failed to detect IRQ line.\n", + mname, ioaddr); + return EAGAIN; + } + } + + outb(AX_RESET+AX_LOOP, AX_CMD); /* Loopback mode. */ + dev->base_addr = ioaddr; + memcpy(dev->dev_addr, station_addr, ETH_ALEN); + + if (dev->mem_start & 0xf) + el_debug = dev->mem_start & 0x7; + if (autoirq) + dev->irq = autoirq; + + printk("%s: %s EtherLink at %#lx, using %sIRQ %d.\n", dev->name, mname, dev->base_addr, + autoirq ? "auto":"assigned ", dev->irq); + +#ifdef CONFIG_IP_MULTICAST + printk("WARNING: Use of the 3c501 in a multicast kernel is NOT recommended.\n"); +#endif + + if (el_debug) + printk("%s", version); + + /* + * Initialize the device structure. + */ + + dev->priv = kmalloc(sizeof(struct net_local), GFP_KERNEL); + if (dev->priv == NULL) + return -ENOMEM; + memset(dev->priv, 0, sizeof(struct net_local)); + + /* + * The EL1-specific entries in the device structure. + */ + + dev->open = &el_open; + dev->hard_start_xmit = &el_start_xmit; + dev->stop = &el1_close; + dev->get_stats = &el1_get_stats; + dev->set_multicast_list = &set_multicast_list; + + /* + * Setup the generic properties + */ + + ether_setup(dev); + +#endif /* !MODULE */ + + return 0; +} + +/* + * Open/initialize the board. + */ + +static int el_open(struct device *dev) +{ + int ioaddr = dev->base_addr; + + if (el_debug > 2) + printk("%s: Doing el_open()...", dev->name); + + if (request_irq(dev->irq, &el_interrupt, 0, "3c501")) + return -EAGAIN; + + irq2dev_map[dev->irq] = dev; + el_reset(dev); + + dev->start = 1; + + outb(AX_RX, AX_CMD); /* Aux control, irq and receive enabled */ + MOD_INC_USE_COUNT; + return 0; +} + +static int el_start_xmit(struct sk_buff *skb, struct device *dev) +{ + struct net_local *lp = (struct net_local *)dev->priv; + int ioaddr = dev->base_addr; + unsigned long flags; + + if(dev->interrupt) /* May be unloading, don't stamp on */ + return 1; /* the packet buffer this time */ + + if (dev->tbusy) + { + if (jiffies - dev->trans_start < 20) + { + if (el_debug > 2) + printk(" transmitter busy, deferred.\n"); + return 1; + } + if (el_debug) + printk ("%s: transmit timed out, txsr %#2x axsr=%02x rxsr=%02x.\n", + dev->name, inb(TX_STATUS), inb(AX_STATUS), inb(RX_STATUS)); + lp->stats.tx_errors++; + outb(TX_NORM, TX_CMD); + outb(RX_NORM, RX_CMD); + outb(AX_OFF, AX_CMD); /* Just trigger a false interrupt. */ + outb(AX_RX, AX_CMD); /* Aux control, irq and receive enabled */ + dev->tbusy = 0; + dev->trans_start = jiffies; + } + + if (skb == NULL) + { + dev_tint(dev); + return 0; + } + + save_flags(flags); + + /* + * Avoid incoming interrupts between us flipping tbusy and flipping + * mode as the driver assumes tbusy is a faithful indicator of card + * state + */ + + cli(); + + /* + * Avoid timer-based retransmission conflicts. + */ + + if (set_bit(0, (void*)&dev->tbusy) != 0) + { + restore_flags(flags); + printk("%s: Transmitter access conflict.\n", dev->name); + } + else + { + int gp_start = 0x800 - (ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN); + unsigned char *buf = skb->data; + +load_it_again_sam: + lp->tx_pkt_start = gp_start; + lp->collisions = 0; + + /* + * Command mode with status cleared should [in theory] + * mean no more interrupts can be pending on the card. + */ + +#ifdef BLOCKOUT_1 + disable_irq(dev->irq); +#endif + outb_p(AX_SYS, AX_CMD); + inb_p(RX_STATUS); + inb_p(TX_STATUS); + + lp->loading=1; + + /* + * Turn interrupts back on while we spend a pleasant afternoon + * loading bytes into the board + */ + + restore_flags(flags); + outw(0x00, RX_BUF_CLR); /* Set rx packet area to 0. */ + outw(gp_start, GP_LOW); /* aim - packet will be loaded into buffer start */ + outsb(DATAPORT,buf,skb->len); /* load buffer (usual thing each byte increments the pointer) */ + outw(gp_start, GP_LOW); /* the board reuses the same register */ +#ifndef BLOCKOUT_1 + if(lp->loading==2) /* A receive upset our load, despite our best efforts */ + { + if(el_debug>2) + printk("%s: burped during tx load.\n", dev->name); + goto load_it_again_sam; /* Sigh... */ + } +#endif + outb(AX_XMIT, AX_CMD); /* fire ... Trigger xmit. */ + lp->loading=0; +#ifdef BLOCKOUT_1 + enable_irq(dev->irq); +#endif + dev->trans_start = jiffies; + } + + if (el_debug > 2) + printk(" queued xmit.\n"); + dev_kfree_skb (skb, FREE_WRITE); + return 0; +} + + +/* + * The typical workload of the driver: + * Handle the ether interface interrupts. + */ + +static void el_interrupt(int irq, struct pt_regs *regs) +{ + struct device *dev = (struct device *)(irq2dev_map[irq]); + struct net_local *lp; + int ioaddr; + int axsr; /* Aux. status reg. */ + + if (dev == NULL || dev->irq != irq) + { + printk ("3c501 driver: irq %d for unknown device.\n", irq); + return; + } + + ioaddr = dev->base_addr; + lp = (struct net_local *)dev->priv; + + /* + * What happened ? + */ + + axsr = inb(AX_STATUS); + + /* + * Log it + */ + + if (el_debug > 3) + printk("%s: el_interrupt() aux=%#02x", dev->name, axsr); + if (dev->interrupt) + printk("%s: Reentering the interrupt driver!\n", dev->name); + dev->interrupt = 1; +#ifndef BLOCKOUT_1 + if(lp->loading==1 && !dev->tbusy) + printk("%s: Inconsistent state loading while not in tx\n", + dev->name); +#endif +#ifdef BLOCKOUT_3 + lp->loading=2; /* So we can spot loading interruptions */ +#endif + + if (dev->tbusy) + { + + /* + * Board in transmit mode. May be loading. If we are + * loading we shouldn't have got this. + */ + + int txsr = inb(TX_STATUS); +#ifdef BLOCKOUT_2 + if(lp->loading==1) + { + if(el_debug > 2) + { + printk("%s: Interrupt while loading [", dev->name); + printk(" txsr=%02x gp=%04x rp=%04x]\n", txsr, inw(GP_LOW),inw(RX_LOW)); + } + lp->loading=2; /* Force a reload */ + dev->interrupt = 0; + return; + } +#endif + if (el_debug > 6) + printk(" txsr=%02x gp=%04x rp=%04x", txsr, inw(GP_LOW),inw(RX_LOW)); + + if ((axsr & 0x80) && (txsr & TX_READY) == 0) + { + /* + * FIXME: is there a logic to whether to keep on trying or + * reset immediately ? + */ + printk("%s: Unusual interrupt during Tx, txsr=%02x axsr=%02x" + " gp=%03x rp=%03x.\n", dev->name, txsr, axsr, + inw(ioaddr + EL1_DATAPTR), inw(ioaddr + EL1_RXPTR)); + dev->tbusy = 0; + mark_bh(NET_BH); + } + else if (txsr & TX_16COLLISIONS) + { + /* + * Timed out + */ + if (el_debug) + printk("%s: Transmit failed 16 times, ethernet jammed?\n",dev->name); + outb(AX_SYS, AX_CMD); + lp->stats.tx_aborted_errors++; + } + else if (txsr & TX_COLLISION) + { + /* + * Retrigger xmit. + */ + + if (el_debug > 6) + printk(" retransmitting after a collision.\n"); + /* + * Poor little chip can't reset its own start pointer + */ + + outb(AX_SYS, AX_CMD); + outw(lp->tx_pkt_start, GP_LOW); + outb(AX_XMIT, AX_CMD); + lp->stats.collisions++; + dev->interrupt = 0; + return; + } + else + { + /* + * It worked.. we will now fall through and receive + */ + lp->stats.tx_packets++; + if (el_debug > 6) + printk(" Tx succeeded %s\n", + (txsr & TX_RDY) ? "." : "but tx is busy!"); + /* + * This is safe the interrupt is atomic WRT itself. + */ + + dev->tbusy = 0; + mark_bh(NET_BH); /* In case more to transmit */ + } + } + else + { + /* + * In receive mode. + */ + + int rxsr = inb(RX_STATUS); + if (el_debug > 5) + printk(" rxsr=%02x txsr=%02x rp=%04x", rxsr, inb(TX_STATUS),inw(RX_LOW)); + /* + * Just reading rx_status fixes most errors. + */ + if (rxsr & RX_MISSED) + lp->stats.rx_missed_errors++; + else if (rxsr & RX_RUNT) + { /* Handled to avoid board lock-up. */ + lp->stats.rx_length_errors++; + if (el_debug > 5) + printk(" runt.\n"); + } + else if (rxsr & RX_GOOD) + { + /* + * Receive worked. + */ + el_receive(dev); + } + else + { + /* + * Nothing? Something is broken! + */ + if (el_debug > 2) + printk("%s: No packet seen, rxsr=%02x **resetting 3c501***\n", + dev->name, rxsr); + el_reset(dev); + } + if (el_debug > 3) + printk(".\n"); + } + + /* + * Move into receive mode + */ + + outb(AX_RX, AX_CMD); + outw(0x00, RX_BUF_CLR); + inb(RX_STATUS); /* Be certain that interrupts are cleared. */ + inb(TX_STATUS); + dev->interrupt = 0; + return; +} + + +/* + * We have a good packet. Well, not really "good", just mostly not broken. + * We must check everything to see if it is good. + */ + +static void el_receive(struct device *dev) +{ + struct net_local *lp = (struct net_local *)dev->priv; + int ioaddr = dev->base_addr; + int pkt_len; + struct sk_buff *skb; + + pkt_len = inw(RX_LOW); + + if (el_debug > 4) + printk(" el_receive %d.\n", pkt_len); + + if ((pkt_len < 60) || (pkt_len > 1536)) + { + if (el_debug) + printk("%s: bogus packet, length=%d\n", dev->name, pkt_len); + lp->stats.rx_over_errors++; + return; + } + + /* + * Command mode so we can empty the buffer + */ + + outb(AX_SYS, AX_CMD); + skb = dev_alloc_skb(pkt_len+2); + + /* + * Start of frame + */ + + outw(0x00, GP_LOW); + if (skb == NULL) + { + printk("%s: Memory squeeze, dropping packet.\n", dev->name); + lp->stats.rx_dropped++; + return; + } + else + { + skb_reserve(skb,2); /* Force 16 byte alignment */ + skb->dev = dev; + /* + * The read increments through the bytes. The interrupt + * handler will fix the pointer when it returns to + * receive mode. + */ + insb(DATAPORT, skb_put(skb,pkt_len), pkt_len); + skb->protocol=eth_type_trans(skb,dev); + netif_rx(skb); + lp->stats.rx_packets++; + } + return; +} + +static void el_reset(struct device *dev) +{ + int ioaddr = dev->base_addr; + + if (el_debug> 2) + printk("3c501 reset..."); + outb(AX_RESET, AX_CMD); /* Reset the chip */ + outb(AX_LOOP, AX_CMD); /* Aux control, irq and loopback enabled */ + { + int i; + for (i = 0; i < 6; i++) /* Set the station address. */ + outb(dev->dev_addr[i], ioaddr + i); + } + + outw(0, RX_BUF_CLR); /* Set rx packet area to 0. */ + cli(); /* Avoid glitch on writes to CMD regs */ + outb(TX_NORM, TX_CMD); /* tx irq on done, collision */ + outb(RX_NORM, RX_CMD); /* Set Rx commands. */ + inb(RX_STATUS); /* Clear status. */ + inb(TX_STATUS); + dev->interrupt = 0; + dev->tbusy = 0; + sti(); +} + +static int el1_close(struct device *dev) +{ + int ioaddr = dev->base_addr; + + if (el_debug > 2) + printk("%s: Shutting down ethercard at %#x.\n", dev->name, ioaddr); + + dev->tbusy = 1; + dev->start = 0; + + /* + * Free and disable the IRQ. + */ + + free_irq(dev->irq); + outb(AX_RESET, AX_CMD); /* Reset the chip */ + irq2dev_map[dev->irq] = 0; + + MOD_DEC_USE_COUNT; + return 0; +} + +static struct enet_statistics *el1_get_stats(struct device *dev) +{ + struct net_local *lp = (struct net_local *)dev->priv; + return &lp->stats; +} + +/* + * Set or clear the multicast filter for this adaptor. + * best-effort filtering. + */ + +static void set_multicast_list(struct device *dev) +{ + int ioaddr = dev->base_addr; + + if(dev->flags&IFF_PROMISC) + { + outb(RX_PROM, RX_CMD); + inb(RX_STATUS); + } + else if (dev->mc_list || dev->flags&IFF_ALLMULTI) + { + outb(RX_MULT, RX_CMD); /* Multicast or all multicast is the same */ + inb(RX_STATUS); /* Clear status. */ + } + else + { + outb(RX_NORM, RX_CMD); + inb(RX_STATUS); + } +} + +#ifdef MODULE + +static char devicename[9] = { 0, }; + +static struct device dev_3c501 = +{ + devicename, /* device name is inserted by linux/drivers/net/net_init.c */ + 0, 0, 0, 0, + 0x280, 5, + 0, 0, 0, NULL, el1_probe +}; + +static int io=0x280; +static int irq=5; + +int init_module(void) +{ + dev_3c501.irq=irq; + dev_3c501.base_addr=io; + if (register_netdev(&dev_3c501) != 0) + return -EIO; + return 0; +} + +void cleanup_module(void) +{ + /* + * No need to check MOD_IN_USE, as sys_delete_module() checks. + */ + + unregister_netdev(&dev_3c501); + + /* + * Free up the private structure, or leak memory :-) + */ + + kfree(dev_3c501.priv); + dev_3c501.priv = NULL; /* gets re-allocated by el1_probe1 */ + + /* + * If we don't do this, we can't re-insmod it later. + */ + release_region(dev_3c501.base_addr, EL1_IO_EXTENT); +} + +#endif /* MODULE */ + +/* + * Local variables: + * compile-command: "gcc -D__KERNEL__ -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer -m486 -c -o 3c501.o 3c501.c" + * kept-new-versions: 5 + * End: + */ |