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-rw-r--r--drivers/net/znet.c948
1 files changed, 948 insertions, 0 deletions
diff --git a/drivers/net/znet.c b/drivers/net/znet.c
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+++ b/drivers/net/znet.c
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+/* 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);