diff options
Diffstat (limited to 'drivers/net/znet.c')
-rw-r--r-- | drivers/net/znet.c | 948 |
1 files changed, 948 insertions, 0 deletions
diff --git a/drivers/net/znet.c b/drivers/net/znet.c new file mode 100644 index 00000000000..3ac047bc727 --- /dev/null +++ b/drivers/net/znet.c @@ -0,0 +1,948 @@ +/* znet.c: An Zenith Z-Note ethernet driver for linux. */ + +/* + Written by Donald Becker. + + The author may be reached as becker@scyld.com. + This driver is based on the Linux skeleton driver. The copyright of the + skeleton driver is held by the United States Government, as represented + by DIRNSA, and it is released under the GPL. + + Thanks to Mike Hollick for alpha testing and suggestions. + + References: + The Crynwr packet driver. + + "82593 CSMA/CD Core LAN Controller" Intel datasheet, 1992 + Intel Microcommunications Databook, Vol. 1, 1990. + As usual with Intel, the documentation is incomplete and inaccurate. + I had to read the Crynwr packet driver to figure out how to actually + use the i82593, and guess at what register bits matched the loosely + related i82586. + + Theory of Operation + + The i82593 used in the Zenith Z-Note series operates using two(!) slave + DMA channels, one interrupt, and one 8-bit I/O port. + + While there several ways to configure '593 DMA system, I chose the one + that seemed commensurate with the highest system performance in the face + of moderate interrupt latency: Both DMA channels are configured as + recirculating ring buffers, with one channel (#0) dedicated to Rx and + the other channel (#1) to Tx and configuration. (Note that this is + different than the Crynwr driver, where the Tx DMA channel is initialized + before each operation. That approach simplifies operation and Tx error + recovery, but requires additional I/O in normal operation and precludes + transmit buffer chaining.) + + Both rings are set to 8192 bytes using {TX,RX}_RING_SIZE. This provides + a reasonable ring size for Rx, while simplifying DMA buffer allocation -- + DMA buffers must not cross a 128K boundary. (In truth the size selection + was influenced by my lack of '593 documentation. I thus was constrained + to use the Crynwr '593 initialization table, which sets the Rx ring size + to 8K.) + + Despite my usual low opinion about Intel-designed parts, I must admit + that the bulk data handling of the i82593 is a good design for + an integrated system, like a laptop, where using two slave DMA channels + doesn't pose a problem. I still take issue with using only a single I/O + port. In the same controlled environment there are essentially no + limitations on I/O space, and using multiple locations would eliminate + the need for multiple operations when looking at status registers, + setting the Rx ring boundary, or switching to promiscuous mode. + + I also question Zenith's selection of the '593: one of the advertised + advantages of earlier Intel parts was that if you figured out the magic + initialization incantation you could use the same part on many different + network types. Zenith's use of the "FriendlyNet" (sic) connector rather + than an on-board transceiver leads me to believe that they were planning + to take advantage of this. But, uhmmm, the '593 omits all but ethernet + functionality from the serial subsystem. + */ + +/* 10/2002 + + o Resurected for Linux 2.5+ by Marc Zyngier <maz@wild-wind.fr.eu.org> : + + - Removed strange DMA snooping in znet_sent_packet, which lead to + TX buffer corruption on my laptop. + - Use init_etherdev stuff. + - Use kmalloc-ed DMA buffers. + - Use as few global variables as possible. + - Use proper resources management. + - Use wireless/i82593.h as much as possible (structure, constants) + - Compiles as module or build-in. + - Now survives unplugging/replugging cable. + + Some code was taken from wavelan_cs. + + Tested on a vintage Zenith Z-Note 433Lnp+. Probably broken on + anything else. Testers (and detailed bug reports) are welcome :-). + + o TODO : + + - Properly handle multicast + - Understand why some traffic patterns add a 1s latency... + */ + +#include <linux/config.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/skbuff.h> +#include <linux/if_arp.h> +#include <linux/bitops.h> + +#include <asm/system.h> +#include <asm/io.h> +#include <asm/dma.h> + +/* This include could be elsewhere, since it is not wireless specific */ +#include "wireless/i82593.h" + +static char version[] __initdata = "znet.c:v1.02 9/23/94 becker@scyld.com\n"; + +#ifndef ZNET_DEBUG +#define ZNET_DEBUG 1 +#endif +static unsigned int znet_debug = ZNET_DEBUG; +module_param (znet_debug, int, 0); +MODULE_PARM_DESC (znet_debug, "ZNet debug level"); +MODULE_LICENSE("GPL"); + +/* The DMA modes we need aren't in <dma.h>. */ +#define DMA_RX_MODE 0x14 /* Auto init, I/O to mem, ++, demand. */ +#define DMA_TX_MODE 0x18 /* Auto init, Mem to I/O, ++, demand. */ +#define dma_page_eq(ptr1, ptr2) ((long)(ptr1)>>17 == (long)(ptr2)>>17) +#define RX_BUF_SIZE 8192 +#define TX_BUF_SIZE 8192 +#define DMA_BUF_SIZE (RX_BUF_SIZE + 16) /* 8k + 16 bytes for trailers */ + +#define TX_TIMEOUT 10 + +struct znet_private { + int rx_dma, tx_dma; + struct net_device_stats stats; + spinlock_t lock; + short sia_base, sia_size, io_size; + struct i82593_conf_block i593_init; + /* The starting, current, and end pointers for the packet buffers. */ + ushort *rx_start, *rx_cur, *rx_end; + ushort *tx_start, *tx_cur, *tx_end; + ushort tx_buf_len; /* Tx buffer length, in words. */ +}; + +/* Only one can be built-in;-> */ +static struct net_device *znet_dev; + +struct netidblk { + char magic[8]; /* The magic number (string) "NETIDBLK" */ + unsigned char netid[8]; /* The physical station address */ + char nettype, globalopt; + char vendor[8]; /* The machine vendor and product name. */ + char product[8]; + char irq1, irq2; /* Interrupts, only one is currently used. */ + char dma1, dma2; + short dma_mem_misc[8]; /* DMA buffer locations (unused in Linux). */ + short iobase1, iosize1; + short iobase2, iosize2; /* Second iobase unused. */ + char driver_options; /* Misc. bits */ + char pad; +}; + +static int znet_open(struct net_device *dev); +static int znet_send_packet(struct sk_buff *skb, struct net_device *dev); +static irqreturn_t znet_interrupt(int irq, void *dev_id, struct pt_regs *regs); +static void znet_rx(struct net_device *dev); +static int znet_close(struct net_device *dev); +static struct net_device_stats *net_get_stats(struct net_device *dev); +static void hardware_init(struct net_device *dev); +static void update_stop_hit(short ioaddr, unsigned short rx_stop_offset); +static void znet_tx_timeout (struct net_device *dev); + +/* Request needed resources */ +static int znet_request_resources (struct net_device *dev) +{ + struct znet_private *znet = dev->priv; + unsigned long flags; + + if (request_irq (dev->irq, &znet_interrupt, 0, "ZNet", dev)) + goto failed; + if (request_dma (znet->rx_dma, "ZNet rx")) + goto free_irq; + if (request_dma (znet->tx_dma, "ZNet tx")) + goto free_rx_dma; + if (!request_region (znet->sia_base, znet->sia_size, "ZNet SIA")) + goto free_tx_dma; + if (!request_region (dev->base_addr, znet->io_size, "ZNet I/O")) + goto free_sia; + + return 0; /* Happy ! */ + + free_sia: + release_region (znet->sia_base, znet->sia_size); + free_tx_dma: + flags = claim_dma_lock(); + free_dma (znet->tx_dma); + release_dma_lock (flags); + free_rx_dma: + flags = claim_dma_lock(); + free_dma (znet->rx_dma); + release_dma_lock (flags); + free_irq: + free_irq (dev->irq, dev); + failed: + return -1; +} + +static void znet_release_resources (struct net_device *dev) +{ + struct znet_private *znet = dev->priv; + unsigned long flags; + + release_region (znet->sia_base, znet->sia_size); + release_region (dev->base_addr, znet->io_size); + flags = claim_dma_lock(); + free_dma (znet->tx_dma); + free_dma (znet->rx_dma); + release_dma_lock (flags); + free_irq (dev->irq, dev); +} + +/* Keep the magical SIA stuff in a single function... */ +static void znet_transceiver_power (struct net_device *dev, int on) +{ + struct znet_private *znet = dev->priv; + unsigned char v; + + /* Turn on/off the 82501 SIA, using zenith-specific magic. */ + /* Select LAN control register */ + outb(0x10, znet->sia_base); + + if (on) + v = inb(znet->sia_base + 1) | 0x84; + else + v = inb(znet->sia_base + 1) & ~0x84; + + outb(v, znet->sia_base+1); /* Turn on/off LAN power (bit 2). */ +} + +/* Init the i82593, with current promisc/mcast configuration. + Also used from hardware_init. */ +static void znet_set_multicast_list (struct net_device *dev) +{ + struct znet_private *znet = dev->priv; + short ioaddr = dev->base_addr; + struct i82593_conf_block *cfblk = &znet->i593_init; + + memset(cfblk, 0x00, sizeof(struct i82593_conf_block)); + + /* The configuration block. What an undocumented nightmare. + The first set of values are those suggested (without explanation) + for ethernet in the Intel 82586 databook. The rest appear to be + completely undocumented, except for cryptic notes in the Crynwr + packet driver. This driver uses the Crynwr values verbatim. */ + + /* maz : Rewritten to take advantage of the wanvelan includes. + At least we have names, not just blind values */ + + /* Byte 0 */ + cfblk->fifo_limit = 10; /* = 16 B rx and 80 B tx fifo thresholds */ + cfblk->forgnesi = 0; /* 0=82C501, 1=AMD7992B compatibility */ + cfblk->fifo_32 = 1; + cfblk->d6mod = 0; /* Run in i82593 advanced mode */ + cfblk->throttle_enb = 1; + + /* Byte 1 */ + cfblk->throttle = 8; /* Continuous w/interrupts, 128-clock DMA. */ + cfblk->cntrxint = 0; /* enable continuous mode receive interrupts */ + cfblk->contin = 1; /* enable continuous mode */ + + /* Byte 2 */ + cfblk->addr_len = ETH_ALEN; + cfblk->acloc = 1; /* Disable source addr insertion by i82593 */ + cfblk->preamb_len = 2; /* 8 bytes preamble */ + cfblk->loopback = 0; /* Loopback off */ + + /* Byte 3 */ + cfblk->lin_prio = 0; /* Default priorities & backoff methods. */ + cfblk->tbofstop = 0; + cfblk->exp_prio = 0; + cfblk->bof_met = 0; + + /* Byte 4 */ + cfblk->ifrm_spc = 6; /* 96 bit times interframe spacing */ + + /* Byte 5 */ + cfblk->slottim_low = 0; /* 512 bit times slot time (low) */ + + /* Byte 6 */ + cfblk->slottim_hi = 2; /* 512 bit times slot time (high) */ + cfblk->max_retr = 15; /* 15 collisions retries */ + + /* Byte 7 */ + cfblk->prmisc = ((dev->flags & IFF_PROMISC) ? 1 : 0); /* Promiscuous mode */ + cfblk->bc_dis = 0; /* Enable broadcast reception */ + cfblk->crs_1 = 0; /* Don't transmit without carrier sense */ + cfblk->nocrc_ins = 0; /* i82593 generates CRC */ + cfblk->crc_1632 = 0; /* 32-bit Autodin-II CRC */ + cfblk->crs_cdt = 0; /* CD not to be interpreted as CS */ + + /* Byte 8 */ + cfblk->cs_filter = 0; /* CS is recognized immediately */ + cfblk->crs_src = 0; /* External carrier sense */ + cfblk->cd_filter = 0; /* CD is recognized immediately */ + + /* Byte 9 */ + cfblk->min_fr_len = ETH_ZLEN >> 2; /* Minimum frame length */ + + /* Byte A */ + cfblk->lng_typ = 1; /* Type/length checks OFF */ + cfblk->lng_fld = 1; /* Disable 802.3 length field check */ + cfblk->rxcrc_xf = 1; /* Don't transfer CRC to memory */ + cfblk->artx = 1; /* Disable automatic retransmission */ + cfblk->sarec = 1; /* Disable source addr trig of CD */ + cfblk->tx_jabber = 0; /* Disable jabber jam sequence */ + cfblk->hash_1 = 1; /* Use bits 0-5 in mc address hash */ + cfblk->lbpkpol = 0; /* Loopback pin active high */ + + /* Byte B */ + cfblk->fdx = 0; /* Disable full duplex operation */ + + /* Byte C */ + cfblk->dummy_6 = 0x3f; /* all ones, Default multicast addresses & backoff. */ + cfblk->mult_ia = 0; /* No multiple individual addresses */ + cfblk->dis_bof = 0; /* Disable the backoff algorithm ?! */ + + /* Byte D */ + cfblk->dummy_1 = 1; /* set to 1 */ + cfblk->tx_ifs_retrig = 3; /* Hmm... Disabled */ + cfblk->mc_all = (dev->mc_list || (dev->flags&IFF_ALLMULTI));/* multicast all mode */ + cfblk->rcv_mon = 0; /* Monitor mode disabled */ + cfblk->frag_acpt = 0; /* Do not accept fragments */ + cfblk->tstrttrs = 0; /* No start transmission threshold */ + + /* Byte E */ + cfblk->fretx = 1; /* FIFO automatic retransmission */ + cfblk->runt_eop = 0; /* drop "runt" packets */ + cfblk->hw_sw_pin = 0; /* ?? */ + cfblk->big_endn = 0; /* Big Endian ? no... */ + cfblk->syncrqs = 1; /* Synchronous DRQ deassertion... */ + cfblk->sttlen = 1; /* 6 byte status registers */ + cfblk->rx_eop = 0; /* Signal EOP on packet reception */ + cfblk->tx_eop = 0; /* Signal EOP on packet transmission */ + + /* Byte F */ + cfblk->rbuf_size = RX_BUF_SIZE >> 12; /* Set receive buffer size */ + cfblk->rcvstop = 1; /* Enable Receive Stop Register */ + + if (znet_debug > 2) { + int i; + unsigned char *c; + + for (i = 0, c = (char *) cfblk; i < sizeof (*cfblk); i++) + printk ("%02X ", c[i]); + printk ("\n"); + } + + *znet->tx_cur++ = sizeof(struct i82593_conf_block); + memcpy(znet->tx_cur, cfblk, sizeof(struct i82593_conf_block)); + znet->tx_cur += sizeof(struct i82593_conf_block)/2; + outb(OP0_CONFIGURE | CR0_CHNL, ioaddr); + + /* XXX FIXME maz : Add multicast addresses here, so having a + * multicast address configured isn't equal to IFF_ALLMULTI */ +} + +/* The Z-Note probe is pretty easy. The NETIDBLK exists in the safe-to-probe + BIOS area. We just scan for the signature, and pull the vital parameters + out of the structure. */ + +static int __init znet_probe (void) +{ + int i; + struct netidblk *netinfo; + struct znet_private *znet; + struct net_device *dev; + char *p; + int err = -ENOMEM; + + /* This code scans the region 0xf0000 to 0xfffff for a "NETIDBLK". */ + for(p = (char *)phys_to_virt(0xf0000); p < (char *)phys_to_virt(0x100000); p++) + if (*p == 'N' && strncmp(p, "NETIDBLK", 8) == 0) + break; + + if (p >= (char *)phys_to_virt(0x100000)) { + if (znet_debug > 1) + printk(KERN_INFO "No Z-Note ethernet adaptor found.\n"); + return -ENODEV; + } + + dev = alloc_etherdev(sizeof(struct znet_private)); + if (!dev) + return -ENOMEM; + + SET_MODULE_OWNER (dev); + + znet = dev->priv; + + netinfo = (struct netidblk *)p; + dev->base_addr = netinfo->iobase1; + dev->irq = netinfo->irq1; + + printk(KERN_INFO "%s: ZNET at %#3lx,", dev->name, dev->base_addr); + + /* The station address is in the "netidblk" at 0x0f0000. */ + for (i = 0; i < 6; i++) + printk(" %2.2x", dev->dev_addr[i] = netinfo->netid[i]); + + printk(", using IRQ %d DMA %d and %d.\n", dev->irq, netinfo->dma1, + netinfo->dma2); + + if (znet_debug > 1) { + printk(KERN_INFO "%s: vendor '%16.16s' IRQ1 %d IRQ2 %d DMA1 %d DMA2 %d.\n", + dev->name, netinfo->vendor, + netinfo->irq1, netinfo->irq2, + netinfo->dma1, netinfo->dma2); + printk(KERN_INFO "%s: iobase1 %#x size %d iobase2 %#x size %d net type %2.2x.\n", + dev->name, netinfo->iobase1, netinfo->iosize1, + netinfo->iobase2, netinfo->iosize2, netinfo->nettype); + } + + if (znet_debug > 0) + printk(KERN_INFO "%s", version); + + znet->rx_dma = netinfo->dma1; + znet->tx_dma = netinfo->dma2; + spin_lock_init(&znet->lock); + znet->sia_base = 0xe6; /* Magic address for the 82501 SIA */ + znet->sia_size = 2; + /* maz: Despite the '593 being advertised above as using a + * single 8bits I/O port, this driver does many 16bits + * access. So set io_size accordingly */ + znet->io_size = 2; + + if (!(znet->rx_start = kmalloc (DMA_BUF_SIZE, GFP_KERNEL | GFP_DMA))) + goto free_dev; + if (!(znet->tx_start = kmalloc (DMA_BUF_SIZE, GFP_KERNEL | GFP_DMA))) + goto free_rx; + + if (!dma_page_eq (znet->rx_start, znet->rx_start + (RX_BUF_SIZE/2-1)) || + !dma_page_eq (znet->tx_start, znet->tx_start + (TX_BUF_SIZE/2-1))) { + printk (KERN_WARNING "tx/rx crossing DMA frontiers, giving up\n"); + goto free_tx; + } + + znet->rx_end = znet->rx_start + RX_BUF_SIZE/2; + znet->tx_buf_len = TX_BUF_SIZE/2; + znet->tx_end = znet->tx_start + znet->tx_buf_len; + + /* The ZNET-specific entries in the device structure. */ + dev->open = &znet_open; + dev->hard_start_xmit = &znet_send_packet; + dev->stop = &znet_close; + dev->get_stats = net_get_stats; + dev->set_multicast_list = &znet_set_multicast_list; + dev->tx_timeout = znet_tx_timeout; + dev->watchdog_timeo = TX_TIMEOUT; + err = register_netdev(dev); + if (err) + goto free_tx; + znet_dev = dev; + return 0; + + free_tx: + kfree(znet->tx_start); + free_rx: + kfree(znet->rx_start); + free_dev: + free_netdev(dev); + return err; +} + + +static int znet_open(struct net_device *dev) +{ + int ioaddr = dev->base_addr; + + if (znet_debug > 2) + printk(KERN_DEBUG "%s: znet_open() called.\n", dev->name); + + /* These should never fail. You can't add devices to a sealed box! */ + if (znet_request_resources (dev)) { + printk(KERN_WARNING "%s: Not opened -- resource busy?!?\n", dev->name); + return -EBUSY; + } + + znet_transceiver_power (dev, 1); + + /* According to the Crynwr driver we should wait 50 msec. for the + LAN clock to stabilize. My experiments indicates that the '593 can + be initialized immediately. The delay is probably needed for the + DC-to-DC converter to come up to full voltage, and for the oscillator + to be spot-on at 20Mhz before transmitting. + Until this proves to be a problem we rely on the higher layers for the + delay and save allocating a timer entry. */ + + /* maz : Well, I'm getting every time the following message + * without the delay on a 486@33. This machine is much too + * fast... :-) So maybe the Crynwr driver wasn't wrong after + * all, even if the message is completly harmless on my + * setup. */ + mdelay (50); + + /* This follows the packet driver's lead, and checks for success. */ + if (inb(ioaddr) != 0x10 && inb(ioaddr) != 0x00) + printk(KERN_WARNING "%s: Problem turning on the transceiver power.\n", + dev->name); + + hardware_init(dev); + netif_start_queue (dev); + + return 0; +} + + +static void znet_tx_timeout (struct net_device *dev) +{ + int ioaddr = dev->base_addr; + ushort event, tx_status, rx_offset, state; + + outb (CR0_STATUS_0, ioaddr); + event = inb (ioaddr); + outb (CR0_STATUS_1, ioaddr); + tx_status = inw (ioaddr); + outb (CR0_STATUS_2, ioaddr); + rx_offset = inw (ioaddr); + outb (CR0_STATUS_3, ioaddr); + state = inb (ioaddr); + printk (KERN_WARNING "%s: transmit timed out, status %02x %04x %04x %02x," + " resetting.\n", dev->name, event, tx_status, rx_offset, state); + if (tx_status == TX_LOST_CRS) + printk (KERN_WARNING "%s: Tx carrier error, check transceiver cable.\n", + dev->name); + outb (OP0_RESET, ioaddr); + hardware_init (dev); + netif_wake_queue (dev); +} + +static int znet_send_packet(struct sk_buff *skb, struct net_device *dev) +{ + int ioaddr = dev->base_addr; + struct znet_private *znet = dev->priv; + unsigned long flags; + short length = skb->len; + + if (znet_debug > 4) + printk(KERN_DEBUG "%s: ZNet_send_packet.\n", dev->name); + + if (length < ETH_ZLEN) { + skb = skb_padto(skb, ETH_ZLEN); + if (skb == NULL) + return 0; + length = ETH_ZLEN; + } + + netif_stop_queue (dev); + + /* Check that the part hasn't reset itself, probably from suspend. */ + outb(CR0_STATUS_0, ioaddr); + if (inw(ioaddr) == 0x0010 && + inw(ioaddr) == 0x0000 && + inw(ioaddr) == 0x0010) { + if (znet_debug > 1) + printk (KERN_WARNING "%s : waking up\n", dev->name); + hardware_init(dev); + znet_transceiver_power (dev, 1); + } + + if (1) { + unsigned char *buf = (void *)skb->data; + ushort *tx_link = znet->tx_cur - 1; + ushort rnd_len = (length + 1)>>1; + + znet->stats.tx_bytes+=length; + + if (znet->tx_cur >= znet->tx_end) + znet->tx_cur = znet->tx_start; + *znet->tx_cur++ = length; + if (znet->tx_cur + rnd_len + 1 > znet->tx_end) { + int semi_cnt = (znet->tx_end - znet->tx_cur)<<1; /* Cvrt to byte cnt. */ + memcpy(znet->tx_cur, buf, semi_cnt); + rnd_len -= semi_cnt>>1; + memcpy(znet->tx_start, buf + semi_cnt, length - semi_cnt); + znet->tx_cur = znet->tx_start + rnd_len; + } else { + memcpy(znet->tx_cur, buf, skb->len); + znet->tx_cur += rnd_len; + } + *znet->tx_cur++ = 0; + + spin_lock_irqsave(&znet->lock, flags); + { + *tx_link = OP0_TRANSMIT | CR0_CHNL; + /* Is this always safe to do? */ + outb(OP0_TRANSMIT | CR0_CHNL, ioaddr); + } + spin_unlock_irqrestore (&znet->lock, flags); + + dev->trans_start = jiffies; + netif_start_queue (dev); + + if (znet_debug > 4) + printk(KERN_DEBUG "%s: Transmitter queued, length %d.\n", dev->name, length); + } + dev_kfree_skb(skb); + return 0; +} + +/* The ZNET interrupt handler. */ +static irqreturn_t znet_interrupt(int irq, void *dev_id, struct pt_regs * regs) +{ + struct net_device *dev = dev_id; + struct znet_private *znet = dev->priv; + int ioaddr; + int boguscnt = 20; + int handled = 0; + + if (dev == NULL) { + printk(KERN_WARNING "znet_interrupt(): IRQ %d for unknown device.\n", irq); + return IRQ_NONE; + } + + spin_lock (&znet->lock); + + ioaddr = dev->base_addr; + + outb(CR0_STATUS_0, ioaddr); + do { + ushort status = inb(ioaddr); + if (znet_debug > 5) { + ushort result, rx_ptr, running; + outb(CR0_STATUS_1, ioaddr); + result = inw(ioaddr); + outb(CR0_STATUS_2, ioaddr); + rx_ptr = inw(ioaddr); + outb(CR0_STATUS_3, ioaddr); + running = inb(ioaddr); + printk(KERN_DEBUG "%s: interrupt, status %02x, %04x %04x %02x serial %d.\n", + dev->name, status, result, rx_ptr, running, boguscnt); + } + if ((status & SR0_INTERRUPT) == 0) + break; + + handled = 1; + + if ((status & SR0_EVENT_MASK) == SR0_TRANSMIT_DONE || + (status & SR0_EVENT_MASK) == SR0_RETRANSMIT_DONE || + (status & SR0_EVENT_MASK) == SR0_TRANSMIT_NO_CRC_DONE) { + int tx_status; + outb(CR0_STATUS_1, ioaddr); + tx_status = inw(ioaddr); + /* It's undocumented, but tx_status seems to match the i82586. */ + if (tx_status & TX_OK) { + znet->stats.tx_packets++; + znet->stats.collisions += tx_status & TX_NCOL_MASK; + } else { + if (tx_status & (TX_LOST_CTS | TX_LOST_CRS)) + znet->stats.tx_carrier_errors++; + if (tx_status & TX_UND_RUN) + znet->stats.tx_fifo_errors++; + if (!(tx_status & TX_HRT_BEAT)) + znet->stats.tx_heartbeat_errors++; + if (tx_status & TX_MAX_COL) + znet->stats.tx_aborted_errors++; + /* ...and the catch-all. */ + if ((tx_status | (TX_LOST_CRS | TX_LOST_CTS | TX_UND_RUN | TX_HRT_BEAT | TX_MAX_COL)) != (TX_LOST_CRS | TX_LOST_CTS | TX_UND_RUN | TX_HRT_BEAT | TX_MAX_COL)) + znet->stats.tx_errors++; + + /* Transceiver may be stuck if cable + * was removed while emiting a + * packet. Flip it off, then on to + * reset it. This is very empirical, + * but it seems to work. */ + + znet_transceiver_power (dev, 0); + znet_transceiver_power (dev, 1); + } + netif_wake_queue (dev); + } + + if ((status & SR0_RECEPTION) || + (status & SR0_EVENT_MASK) == SR0_STOP_REG_HIT) { + znet_rx(dev); + } + /* Clear the interrupts we've handled. */ + outb(CR0_INT_ACK, ioaddr); + } while (boguscnt--); + + spin_unlock (&znet->lock); + + return IRQ_RETVAL(handled); +} + +static void znet_rx(struct net_device *dev) +{ + struct znet_private *znet = dev->priv; + int ioaddr = dev->base_addr; + int boguscount = 1; + short next_frame_end_offset = 0; /* Offset of next frame start. */ + short *cur_frame_end; + short cur_frame_end_offset; + + outb(CR0_STATUS_2, ioaddr); + cur_frame_end_offset = inw(ioaddr); + + if (cur_frame_end_offset == znet->rx_cur - znet->rx_start) { + printk(KERN_WARNING "%s: Interrupted, but nothing to receive, offset %03x.\n", + dev->name, cur_frame_end_offset); + return; + } + + /* Use same method as the Crynwr driver: construct a forward list in + the same area of the backwards links we now have. This allows us to + pass packets to the upper layers in the order they were received -- + important for fast-path sequential operations. */ + while (znet->rx_start + cur_frame_end_offset != znet->rx_cur + && ++boguscount < 5) { + unsigned short hi_cnt, lo_cnt, hi_status, lo_status; + int count, status; + + if (cur_frame_end_offset < 4) { + /* Oh no, we have a special case: the frame trailer wraps around + the end of the ring buffer. We've saved space at the end of + the ring buffer for just this problem. */ + memcpy(znet->rx_end, znet->rx_start, 8); + cur_frame_end_offset += (RX_BUF_SIZE/2); + } + cur_frame_end = znet->rx_start + cur_frame_end_offset - 4; + + lo_status = *cur_frame_end++; + hi_status = *cur_frame_end++; + status = ((hi_status & 0xff) << 8) + (lo_status & 0xff); + lo_cnt = *cur_frame_end++; + hi_cnt = *cur_frame_end++; + count = ((hi_cnt & 0xff) << 8) + (lo_cnt & 0xff); + + if (znet_debug > 5) + printk(KERN_DEBUG "Constructing trailer at location %03x, %04x %04x %04x %04x" + " count %#x status %04x.\n", + cur_frame_end_offset<<1, lo_status, hi_status, lo_cnt, hi_cnt, + count, status); + cur_frame_end[-4] = status; + cur_frame_end[-3] = next_frame_end_offset; + cur_frame_end[-2] = count; + next_frame_end_offset = cur_frame_end_offset; + cur_frame_end_offset -= ((count + 1)>>1) + 3; + if (cur_frame_end_offset < 0) + cur_frame_end_offset += RX_BUF_SIZE/2; + }; + + /* Now step forward through the list. */ + do { + ushort *this_rfp_ptr = znet->rx_start + next_frame_end_offset; + int status = this_rfp_ptr[-4]; + int pkt_len = this_rfp_ptr[-2]; + + if (znet_debug > 5) + printk(KERN_DEBUG "Looking at trailer ending at %04x status %04x length %03x" + " next %04x.\n", next_frame_end_offset<<1, status, pkt_len, + this_rfp_ptr[-3]<<1); + /* Once again we must assume that the i82586 docs apply. */ + if ( ! (status & RX_RCV_OK)) { /* There was an error. */ + znet->stats.rx_errors++; + if (status & RX_CRC_ERR) znet->stats.rx_crc_errors++; + if (status & RX_ALG_ERR) znet->stats.rx_frame_errors++; +#if 0 + if (status & 0x0200) znet->stats.rx_over_errors++; /* Wrong. */ + if (status & 0x0100) znet->stats.rx_fifo_errors++; +#else + /* maz : Wild guess... */ + if (status & RX_OVRRUN) znet->stats.rx_over_errors++; +#endif + if (status & RX_SRT_FRM) znet->stats.rx_length_errors++; + } else if (pkt_len > 1536) { + znet->stats.rx_length_errors++; + } else { + /* Malloc up new buffer. */ + struct sk_buff *skb; + + skb = dev_alloc_skb(pkt_len); + if (skb == NULL) { + if (znet_debug) + printk(KERN_WARNING "%s: Memory squeeze, dropping packet.\n", dev->name); + znet->stats.rx_dropped++; + break; + } + skb->dev = dev; + + if (&znet->rx_cur[(pkt_len+1)>>1] > znet->rx_end) { + int semi_cnt = (znet->rx_end - znet->rx_cur)<<1; + memcpy(skb_put(skb,semi_cnt), znet->rx_cur, semi_cnt); + memcpy(skb_put(skb,pkt_len-semi_cnt), znet->rx_start, + pkt_len - semi_cnt); + } else { + memcpy(skb_put(skb,pkt_len), znet->rx_cur, pkt_len); + if (znet_debug > 6) { + unsigned int *packet = (unsigned int *) skb->data; + printk(KERN_DEBUG "Packet data is %08x %08x %08x %08x.\n", packet[0], + packet[1], packet[2], packet[3]); + } + } + skb->protocol=eth_type_trans(skb,dev); + netif_rx(skb); + dev->last_rx = jiffies; + znet->stats.rx_packets++; + znet->stats.rx_bytes += pkt_len; + } + znet->rx_cur = this_rfp_ptr; + if (znet->rx_cur >= znet->rx_end) + znet->rx_cur -= RX_BUF_SIZE/2; + update_stop_hit(ioaddr, (znet->rx_cur - znet->rx_start)<<1); + next_frame_end_offset = this_rfp_ptr[-3]; + if (next_frame_end_offset == 0) /* Read all the frames? */ + break; /* Done for now */ + this_rfp_ptr = znet->rx_start + next_frame_end_offset; + } while (--boguscount); + + /* If any worth-while packets have been received, dev_rint() + has done a mark_bh(INET_BH) for us and will work on them + when we get to the bottom-half routine. */ + return; +} + +/* The inverse routine to znet_open(). */ +static int znet_close(struct net_device *dev) +{ + int ioaddr = dev->base_addr; + + netif_stop_queue (dev); + + outb(OP0_RESET, ioaddr); /* CMD0_RESET */ + + if (znet_debug > 1) + printk(KERN_DEBUG "%s: Shutting down ethercard.\n", dev->name); + /* Turn off transceiver power. */ + znet_transceiver_power (dev, 0); + + znet_release_resources (dev); + + return 0; +} + +/* Get the current statistics. This may be called with the card open or + closed. */ +static struct net_device_stats *net_get_stats(struct net_device *dev) +{ + struct znet_private *znet = dev->priv; + + return &znet->stats; +} + +static void show_dma(struct net_device *dev) +{ + short ioaddr = dev->base_addr; + unsigned char stat = inb (ioaddr); + struct znet_private *znet = dev->priv; + unsigned long flags; + short dma_port = ((znet->tx_dma&3)<<2) + IO_DMA2_BASE; + unsigned addr = inb(dma_port); + short residue; + + addr |= inb(dma_port) << 8; + residue = get_dma_residue(znet->tx_dma); + + if (znet_debug > 1) { + flags=claim_dma_lock(); + printk(KERN_DEBUG "Stat:%02x Addr: %04x cnt:%3x\n", + stat, addr<<1, residue); + release_dma_lock(flags); + } +} + +/* Initialize the hardware. We have to do this when the board is open()ed + or when we come out of suspend mode. */ +static void hardware_init(struct net_device *dev) +{ + unsigned long flags; + short ioaddr = dev->base_addr; + struct znet_private *znet = dev->priv; + + znet->rx_cur = znet->rx_start; + znet->tx_cur = znet->tx_start; + + /* Reset the chip, and start it up. */ + outb(OP0_RESET, ioaddr); + + flags=claim_dma_lock(); + disable_dma(znet->rx_dma); /* reset by an interrupting task. */ + clear_dma_ff(znet->rx_dma); + set_dma_mode(znet->rx_dma, DMA_RX_MODE); + set_dma_addr(znet->rx_dma, (unsigned int) znet->rx_start); + set_dma_count(znet->rx_dma, RX_BUF_SIZE); + enable_dma(znet->rx_dma); + /* Now set up the Tx channel. */ + disable_dma(znet->tx_dma); + clear_dma_ff(znet->tx_dma); + set_dma_mode(znet->tx_dma, DMA_TX_MODE); + set_dma_addr(znet->tx_dma, (unsigned int) znet->tx_start); + set_dma_count(znet->tx_dma, znet->tx_buf_len<<1); + enable_dma(znet->tx_dma); + release_dma_lock(flags); + + if (znet_debug > 1) + printk(KERN_DEBUG "%s: Initializing the i82593, rx buf %p tx buf %p\n", + dev->name, znet->rx_start,znet->tx_start); + /* Do an empty configure command, just like the Crynwr driver. This + resets to chip to its default values. */ + *znet->tx_cur++ = 0; + *znet->tx_cur++ = 0; + show_dma(dev); + outb(OP0_CONFIGURE | CR0_CHNL, ioaddr); + + znet_set_multicast_list (dev); + + *znet->tx_cur++ = 6; + memcpy(znet->tx_cur, dev->dev_addr, 6); + znet->tx_cur += 3; + show_dma(dev); + outb(OP0_IA_SETUP | CR0_CHNL, ioaddr); + show_dma(dev); + + update_stop_hit(ioaddr, 8192); + if (znet_debug > 1) printk(KERN_DEBUG "enabling Rx.\n"); + outb(OP0_RCV_ENABLE, ioaddr); + netif_start_queue (dev); +} + +static void update_stop_hit(short ioaddr, unsigned short rx_stop_offset) +{ + outb(OP0_SWIT_TO_PORT_1 | CR0_CHNL, ioaddr); + if (znet_debug > 5) + printk(KERN_DEBUG "Updating stop hit with value %02x.\n", + (rx_stop_offset >> 6) | CR1_STOP_REG_UPDATE); + outb((rx_stop_offset >> 6) | CR1_STOP_REG_UPDATE, ioaddr); + outb(OP1_SWIT_TO_PORT_0, ioaddr); +} + +static __exit void znet_cleanup (void) +{ + if (znet_dev) { + struct znet_private *znet = znet_dev->priv; + + unregister_netdev (znet_dev); + kfree (znet->rx_start); + kfree (znet->tx_start); + free_netdev (znet_dev); + } +} + +module_init (znet_probe); +module_exit (znet_cleanup); |