patch-2.1.79 linux/drivers/net/dmascc.c

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diff -u --recursive --new-file v2.1.78/linux/drivers/net/dmascc.c linux/drivers/net/dmascc.c
@@ -1,1260 +0,0 @@
-/*
- * $Id: dmascc.c,v 1.2 1997/12/02 16:49:49 oe1kib Exp $
- *
- * Driver for high-speed SCC boards (those with DMA support)
- * Copyright (C) 1997 Klaus Kudielka
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-
-#include <linux/module.h>
-#include <linux/dmascc.h>
-#include <linux/errno.h>
-#include <linux/if_arp.h>
-#include <linux/in.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/ioport.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/netdevice.h>
-#include <linux/sockios.h>
-#include <linux/tqueue.h>
-#include <linux/version.h>
-#include <asm/atomic.h>
-#include <asm/bitops.h>
-#include <asm/dma.h>
-#include <asm/io.h>
-#include <asm/irq.h>
-#include <asm/segment.h>
-#include <asm/uaccess.h>
-#include <net/ax25.h>
-#include <stdio.h>
-#include "z8530.h"
-
-
-/* Number of buffers per channel */
-
-#define NUM_TX_BUF      2          /* NUM_TX_BUF >= 1 (2 recommended) */
-#define NUM_RX_BUF      2          /* NUM_RX_BUF >= 1 (2 recommended) */
-#define BUF_SIZE        2016
-
-
-/* Cards supported */
-
-#define HW_PI           { "Ottawa PI", 0x300, 0x20, 0x10, 8, \
-                            0, 8, 1843200, 3686400 }
-#define HW_PI2          { "Ottawa PI2", 0x300, 0x20, 0x10, 8, \
-			    0, 8, 3686400, 7372800 }
-#define HW_TWIN         { "Gracilis PackeTwin", 0x200, 0x10, 0x10, 32, \
-			    0, 4, 6144000, 6144000 }
-
-#define HARDWARE        { HW_PI, HW_PI2, HW_TWIN }
-
-#define TYPE_PI         0
-#define TYPE_PI2        1
-#define TYPE_TWIN       2
-#define NUM_TYPES       3
-
-#define MAX_NUM_DEVS    32
-
-
-/* SCC chips supported */
-
-#define Z8530           0
-#define Z85C30          1
-#define Z85230          2
-
-#define CHIPNAMES       { "Z8530", "Z85C30", "Z85230" }
-
-
-/* I/O registers */
-
-/* 8530 registers relative to card base */
-#define SCCB_CMD        0x00
-#define SCCB_DATA       0x01
-#define SCCA_CMD        0x02
-#define SCCA_DATA       0x03
-
-/* 8254 registers relative to card base */
-#define TMR_CNT0        0x00
-#define TMR_CNT1        0x01
-#define TMR_CNT2        0x02
-#define TMR_CTRL        0x03
-
-/* Additional PI/PI2 registers relative to card base */
-#define PI_DREQ_MASK    0x04
-
-/* Additional PackeTwin registers relative to card base */
-#define TWIN_INT_REG    0x08
-#define TWIN_CLR_TMR1   0x09
-#define TWIN_CLR_TMR2   0x0a
-#define TWIN_SPARE_1    0x0b
-#define TWIN_DMA_CFG    0x08
-#define TWIN_SERIAL_CFG 0x09
-#define TWIN_DMA_CLR_FF 0x0a
-#define TWIN_SPARE_2    0x0b
-
-
-/* PackeTwin I/O register values */
-
-/* INT_REG */
-#define TWIN_SCC_MSK       0x01
-#define TWIN_TMR1_MSK      0x02
-#define TWIN_TMR2_MSK      0x04
-#define TWIN_INT_MSK       0x07
-
-/* SERIAL_CFG */
-#define TWIN_DTRA_ON       0x01
-#define TWIN_DTRB_ON       0x02
-#define TWIN_EXTCLKA       0x04
-#define TWIN_EXTCLKB       0x08
-#define TWIN_LOOPA_ON      0x10
-#define TWIN_LOOPB_ON      0x20
-#define TWIN_EI            0x80
-
-/* DMA_CFG */
-#define TWIN_DMA_HDX_T1    0x08
-#define TWIN_DMA_HDX_R1    0x0a
-#define TWIN_DMA_HDX_T3    0x14
-#define TWIN_DMA_HDX_R3    0x16
-#define TWIN_DMA_FDX_T3R1  0x1b
-#define TWIN_DMA_FDX_T1R3  0x1d
-
-
-/* Status values */
-
-/* tx_state */
-#define TX_IDLE    0
-#define TX_OFF     1
-#define TX_TXDELAY 2
-#define TX_ACTIVE  3
-#define TX_SQDELAY 4
-
-
-/* Data types */
-
-struct scc_hardware {
-  char *name;
-  int io_region;
-  int io_delta;
-  int io_size;
-  int num_devs;
-  int scc_offset;
-  int tmr_offset;
-  int tmr_hz;
-  int pclk_hz;
-};
-
-struct scc_priv {
-  char name[10];
-  struct enet_statistics stats;
-  struct scc_info *info;
-  int channel;
-  int cmd, data, tmr;
-  struct scc_param param;
-  char rx_buf[NUM_RX_BUF][BUF_SIZE];
-  int rx_len[NUM_RX_BUF];
-  int rx_ptr;
-  struct tq_struct rx_task;
-  int rx_head, rx_tail, rx_count;
-  int rx_over;
-  char tx_buf[NUM_TX_BUF][BUF_SIZE];
-  int tx_len[NUM_TX_BUF];
-  int tx_ptr;
-  int tx_head, tx_tail, tx_count;
-  int tx_sem, tx_state;
-  unsigned long tx_start;
-  int status;
-};
-
-struct scc_info {
-  int type;
-  int chip;
-  int open;
-  int scc_base;
-  int tmr_base;
-  int twin_serial_cfg;
-  struct device dev[2];
-  struct scc_priv priv[2];
-  struct scc_info *next;
-};
-
-
-/* Function declarations */
-
-int dmascc_init(void) __init;
-static int setup_adapter(int io, int h, int n) __init;
-
-static inline void write_scc(int ctl, int reg, int val);
-static inline int read_scc(int ctl, int reg);
-static int scc_open(struct device *dev);
-static int scc_close(struct device *dev);
-static int scc_ioctl(struct device *dev, struct ifreq *ifr, int cmd);
-static int scc_send_packet(struct sk_buff *skb, struct device *dev);
-static struct enet_statistics *scc_get_stats(struct device *dev);
-static int scc_set_mac_address(struct device *dev, void *sa);
-static void scc_isr(int irq, void *dev_id, struct pt_regs * regs);
-static inline void z8530_isr(struct scc_info *info);
-static void rx_isr(struct device *dev);
-static void special_condition(struct device *dev, int rc);
-static void rx_bh(void *arg);
-static void tx_isr(struct device *dev);
-static void es_isr(struct device *dev);
-static void tm_isr(struct device *dev);
-static inline void delay(struct device *dev, int t);
-static inline unsigned char random(void);
-
-
-/* Initialization variables */
-
-static int io[MAX_NUM_DEVS] __initdata = { 0, };
-/* Beware! hw[] is also used in cleanup_module(). If __initdata also applies
-   to modules, we may not declare hw[] as __initdata */
-static struct scc_hardware hw[NUM_TYPES] __initdata = HARDWARE;
-static char ax25_broadcast[7] __initdata =
-  { 'Q'<<1, 'S'<<1, 'T'<<1, ' '<<1, ' '<<1, ' '<<1, '0'<<1 };
-static char ax25_test[7] __initdata =
-  { 'L'<<1, 'I'<<1, 'N'<<1, 'U'<<1, 'X'<<1, ' '<<1, '1'<<1 };
-
-
-/* Global variables */
-
-static struct scc_info *first = NULL;
-static unsigned long rand;
-
-
-
-/* Module functions */
-
-#ifdef MODULE
-
-
-MODULE_AUTHOR("Klaus Kudielka <oe1kib@oe1xtu.ampr.org>");
-MODULE_DESCRIPTION("Driver for high-speed SCC boards");
-MODULE_PARM(io, "1-" __MODULE_STRING(MAX_NUM_DEVS) "i");
-
-
-int init_module(void)
-{
-  return dmascc_init();
-}
-
-
-void cleanup_module(void)
-{
-  int i;
-  struct scc_info *info;
-
-  while (first) {
-    info = first;
-
-    /* Unregister devices */
-    for (i = 0; i < 2; i++) {
-      if (info->dev[i].name)
-	unregister_netdev(&info->dev[i]);
-    }
-
-    /* Reset board */
-    if (info->type == TYPE_TWIN)
-      outb_p(0, info->dev[0].base_addr + TWIN_SERIAL_CFG);
-    write_scc(info->priv[0].cmd, R9, FHWRES);
-    release_region(info->dev[0].base_addr,
-		   hw[info->type].io_size);
-
-    /* Free memory */
-    first = info->next;
-    kfree_s(info, sizeof(struct scc_info));
-  }
-}
-
-
-#else
-
-
-__initfunc(void dmascc_setup(char *str, int *ints))
-{
-   int i;
-
-   for (i = 0; i < MAX_NUM_DEVS && i < ints[0]; i++)
-      io[i] = ints[i+1];
-}
-
-
-#endif
-
-
-/* Initialization functions */
-
-__initfunc(int dmascc_init(void))
-{
-  int h, i, j, n, base[MAX_NUM_DEVS], tcmd, t0, t1, status;
-  unsigned long time, start[MAX_NUM_DEVS], stop[MAX_NUM_DEVS];
-
-  /* Initialize random number generator */
-  rand = jiffies;
-
-  /* Cards found = 0 */
-  n = 0;
-
-  /* Run autodetection for each card type */
-  for (h = 0; h < NUM_TYPES; h++) {
-
-    if (io[0]) {
-      /* User-specified I/O address regions */
-      for (i = 0; i < hw[h].num_devs; i++) base[i] = 0;
-      for (i = 0; i < MAX_NUM_DEVS && io[i]; i++) {
-	j = (io[i] - hw[h].io_region) / hw[h].io_delta;
-	if (j >= 0 &&
-	    j < hw[h].num_devs && 
-	    hw[h].io_region + j * hw[h].io_delta == io[i])
-	  base[j] = io[i];
-      }
-    } else {
-      /* Default I/O address regions */
-      for (i = 0; i < hw[h].num_devs; i++)
-	base[i] = hw[h].io_region + i * hw[h].io_delta;
-    }
-
-    /* Check valid I/O address regions */
-    for (i = 0; i < hw[h].num_devs; i++)
-      if (base[i] && check_region(base[i], hw[h].io_size))
-	base[i] = 0;
-
-    /* Start timers */
-    for (i = 0; i < hw[h].num_devs; i++)
-      if (base[i]) {
-	tcmd = base[i] + hw[h].tmr_offset + TMR_CTRL;
-	t0   = base[i] + hw[h].tmr_offset + TMR_CNT0;
-	t1   = base[i] + hw[h].tmr_offset + TMR_CNT1;
-	/* Timer 0: LSB+MSB, Mode 3, TMR_0_HZ */
-	outb_p(0x36, tcmd);
-	outb_p((hw[h].tmr_hz/TMR_0_HZ) & 0xFF, t0);
-	outb_p((hw[h].tmr_hz/TMR_0_HZ) >> 8, t0);
-	/* Timer 1: LSB+MSB, Mode 0, HZ/10 */
-	outb_p(0x70, tcmd);
-	outb_p((TMR_0_HZ/HZ*10) & 0xFF, t1);
-	outb_p((TMR_0_HZ/HZ*10) >> 8, t1);
-	/* Timer 2: LSB+MSB, Mode 0 */
-	outb_p(0xb0, tcmd);
-      }
-
-    /* Initialize start values in case we miss the null count bit */
-    time = jiffies;
-    for (i = 0; i < hw[h].num_devs; i++) start[i] = time;
-
-    /* Timing loop */
-    while (jiffies - time < 12) {
-      for (i = 0; i < hw[h].num_devs; i++)
-	if (base[i]) {
-	  /* Read back Timer 1: Status */
-	  outb_p(0xE4, base[i] + hw[h].tmr_offset + TMR_CTRL);
-	  status = inb_p(base[i] + hw[h].tmr_offset + TMR_CNT1);
-	  if ((status & 0x3F) != 0x30) base[i] = 0;
-	  if (status & 0x40) start[i] = jiffies;
-	  if (~status & 0x80) stop[i] = jiffies;
-	}
-    }
-
-    /* Evaluate measurements */
-    for (i = 0; i < hw[h].num_devs; i++)
-      if (base[i]) {
-	time = stop[i] - start[i];
-	if (time < 9 || time > 11)
-	  /* The time expired doesn't match */
-	  base[i] = 0;
-	else {
-	  /* Ok, we have found an adapter */
-	  if (setup_adapter(base[i], h, n) == 0)
-	    n++;
-	}
-      }
-
-  } /* NUM_TYPES */
-
-  /* If any adapter was successfully initialized, return ok */
-  if (n) return 0;
-
-  /* If no adapter found, return error */
-  printk("dmascc: no adapters found\n");
-  return -EIO;
-}
-
-
-__initfunc(int setup_adapter(int io, int h, int n))
-{
-  int i, irq, chip;
-  struct scc_info *info;
-  struct device *dev;
-  struct scc_priv *priv;
-  unsigned long time;
-  unsigned int irqs;
-  int tmr = io + hw[h].tmr_offset;
-  int scc = io + hw[h].scc_offset;
-  int cmd = scc + SCCA_CMD;
-  char *chipnames[] = CHIPNAMES;
-
-  /* Reset 8530 */
-  write_scc(cmd, R9, FHWRES | MIE | NV);
-
-  /* Determine type of chip */
-  write_scc(cmd, R15, 1);
-  if (!read_scc(cmd, R15)) {
-    /* WR7' not present. This is an ordinary Z8530 SCC. */
-    chip = Z8530;
-  } else {
-    /* Put one character in TX FIFO */
-    write_scc(cmd, R8, 0);
-    if (read_scc(cmd, R0) & Tx_BUF_EMP) {
-      /* TX FIFO not full. This is a Z85230 ESCC with a 4-byte FIFO. */
-      chip = Z85230;
-    } else {
-      /* TX FIFO full. This is a Z85C30 SCC with a 1-byte FIFO. */
-      chip = Z85C30;
-    }
-  }
-  write_scc(cmd, R15, 0);
-
-  /* Start IRQ auto-detection */
-  sti();
-  irqs = probe_irq_on();
-
-  /* Enable interrupts */
-  switch (h) {
-  case TYPE_PI:
-  case TYPE_PI2:
-    outb_p(0, io + PI_DREQ_MASK);
-    write_scc(cmd, R15, CTSIE);
-    write_scc(cmd, R0, RES_EXT_INT);
-    write_scc(cmd, R1, EXT_INT_ENAB);
-    break;
-  case TYPE_TWIN:
-    outb_p(0, io + TWIN_DMA_CFG);
-    inb_p(io + TWIN_CLR_TMR1);
-    inb_p(io + TWIN_CLR_TMR2);
-    outb_p(TWIN_EI, io + TWIN_SERIAL_CFG);
-    break;
-  }
-
-  /* Start timer */
-  outb_p(1, tmr + TMR_CNT1);
-  outb_p(0, tmr + TMR_CNT1);
-  /* Wait and detect IRQ */
-  time = jiffies; while (jiffies - time < 2 + HZ / TMR_0_HZ);
-  irq = probe_irq_off(irqs);
-
-  /* Clear pending interrupt, disable interrupts */
-  switch (h) {
-  case TYPE_PI:
-  case TYPE_PI2:
-    write_scc(cmd, R1, 0);
-    write_scc(cmd, R15, 0);
-    write_scc(cmd, R0, RES_EXT_INT);
-    break;
-  case TYPE_TWIN:
-    inb_p(io + TWIN_CLR_TMR1);
-    outb_p(0, io + TWIN_SERIAL_CFG);
-    break;
-  }
-
-  if (irq <= 0) {
-    printk("dmascc: could not find irq of %s at %#3x (irq=%d)\n",
-	   hw[h].name, io, irq);
-    return -1;
-  }
-
-  /* Allocate memory */
-  info = kmalloc(sizeof(struct scc_info), GFP_KERNEL | GFP_DMA);
-  if (!info) {
-    printk("dmascc: could not allocate memory for %s at %#3x\n",
-	   hw[h].name, io);
-    return -1;
-  }
-
-  /* Set up data structures */
-  memset(info, 0, sizeof(struct scc_info));
-  info->type = h;
-  info->chip = chip;
-  info->scc_base = io + hw[h].scc_offset;
-  info->tmr_base = io + hw[h].tmr_offset;
-  info->twin_serial_cfg = 0;
-  for (i = 0; i < 2; i++) {
-    dev = &info->dev[i];
-    priv = &info->priv[i];
-    sprintf(priv->name, "dmascc%i", 2*n+i);
-    priv->info = info;
-    priv->channel = i;
-    priv->cmd = info->scc_base + (i ? SCCB_CMD : SCCA_CMD);
-    priv->data = info->scc_base + (i ? SCCB_DATA : SCCA_DATA);
-    priv->tmr = info->tmr_base + (i ? TMR_CNT2 : TMR_CNT1);
-    priv->param.pclk_hz = hw[h].pclk_hz;
-    priv->param.brg_tc = -1;
-    priv->param.clocks = TCTRxCP | RCRTxCP;
-    priv->param.txdelay = TMR_0_HZ * 10 / 1000;
-    priv->param.txtime = HZ * 3;
-    priv->param.sqdelay = TMR_0_HZ * 1 / 1000;
-    priv->param.slottime = TMR_0_HZ * 10 / 1000;
-    priv->param.waittime = TMR_0_HZ * 100 / 1000;
-    priv->param.persist = 32;
-    priv->rx_task.routine = rx_bh;
-    priv->rx_task.data = dev;
-    dev->priv = priv;
-    dev->name = priv->name;
-    dev->base_addr = io;
-    dev->irq = irq;
-    dev->open = scc_open;
-    dev->stop = scc_close;
-    dev->do_ioctl = scc_ioctl;
-    dev->hard_start_xmit = scc_send_packet;
-    dev->get_stats = scc_get_stats;
-    dev->hard_header = ax25_encapsulate;
-    dev->rebuild_header = ax25_rebuild_header;
-    dev->set_mac_address = scc_set_mac_address;
-    dev->type = ARPHRD_AX25;
-    dev->hard_header_len = 73;
-    dev->mtu = 1500;
-    dev->addr_len = 7;
-    dev->tx_queue_len = 64;
-    memcpy(dev->broadcast, ax25_broadcast, 7);
-    memcpy(dev->dev_addr, ax25_test, 7);
-    dev->flags = 0;
-    dev_init_buffers(dev);
-    if (register_netdev(dev)) {
-      printk("dmascc: could not register %s\n", dev->name);
-      dev->name = NULL;
-    }
-  }
-
-  request_region(io, hw[h].io_size, "dmascc");
-
-  info->next = first;
-  first = info;
-  printk("dmascc: found %s (%s) at %#3x, irq %d\n", hw[h].name,
-	 chipnames[chip], io, irq);
-  return 0;
-}
-
-
-/* Driver functions */
-
-static inline void write_scc(int ctl, int reg, int val)
-{
-  outb_p(reg, ctl);
-  outb_p(val, ctl);
-}
-
-
-static inline int read_scc(int ctl, int reg)
-{
-  outb_p(reg, ctl);
-  return inb_p(ctl);
-}
-
-
-static int scc_open(struct device *dev)
-{
-  struct scc_priv *priv = dev->priv;
-  struct scc_info *info = priv->info;
-  int io = dev->base_addr;
-  int cmd = priv->cmd;
-
-  /* Request IRQ if not already used by other channel */
-  if (!info->open) {
-    if (request_irq(dev->irq, scc_isr, SA_INTERRUPT, "dmascc", info))
-      return -EAGAIN;
-  }
-
-  /* Request DMA if required */
-  if (dev->dma && request_dma(dev->dma, "dmascc")) {
-    if (!info->open) free_irq(dev->irq, info);
-    return -EAGAIN;
-  }
-
-  /* Initialize local variables */
-  dev->tbusy = 0;
-  priv->rx_ptr = 0;
-  priv->rx_over = 0;
-  priv->rx_head = priv->rx_tail = priv->rx_count = 0;
-  priv->tx_state = TX_IDLE;
-  priv->tx_head = priv->tx_tail = priv->tx_count = 0;
-  priv->tx_ptr = 0;
-  priv->tx_sem = 0;
-
-  /* Reset channel */
-  write_scc(cmd, R9, (priv->channel ? CHRB : CHRA) | MIE | NV);
-  /* X1 clock, SDLC mode */
-  write_scc(cmd, R4, SDLC | X1CLK);
-  /* DMA */
-  write_scc(cmd, R1, EXT_INT_ENAB | WT_FN_RDYFN);
-  /* 8 bit RX char, RX disable */
-  write_scc(cmd, R3, Rx8);
-  /* 8 bit TX char, TX disable */
-  write_scc(cmd, R5, Tx8);
-  /* SDLC address field */
-  write_scc(cmd, R6, 0);
-  /* SDLC flag */
-  write_scc(cmd, R7, FLAG);
-  switch (info->chip) {
-  case Z85C30:
-    /* Select WR7' */
-    write_scc(cmd, R15, 1);
-    /* Auto EOM reset */
-    write_scc(cmd, R7, 0x02);
-    write_scc(cmd, R15, 0);
-    break;
-  case Z85230:
-    /* Select WR7' */
-    write_scc(cmd, R15, 1);
-    /* RX FIFO half full (interrupt only), Auto EOM reset,
-       TX FIFO empty (DMA only) */
-    write_scc(cmd, R7, dev->dma ? 0x22 : 0x0a);
-    write_scc(cmd, R15, 0);
-    break;
-  }
-  /* Preset CRC, NRZ(I) encoding */
-  write_scc(cmd, R10, CRCPS | (priv->param.nrzi ? NRZI : NRZ));
-
-  /* Configure baud rate generator */
-  if (priv->param.brg_tc >= 0) {
-    /* Program BR generator */
-    write_scc(cmd, R12, priv->param.brg_tc & 0xFF);
-    write_scc(cmd, R13, (priv->param.brg_tc>>8) & 0xFF);
-    /* BRG source = SYS CLK; enable BRG; DTR REQ function (required by
-       PackeTwin, not connected on the PI2); set DPLL source to BRG */
-    write_scc(cmd, R14, SSBR | DTRREQ | BRSRC | BRENABL);
-    /* Enable DPLL */
-    write_scc(cmd, R14, SEARCH | DTRREQ | BRSRC | BRENABL);
-  } else {
-    /* Disable BR generator */
-    write_scc(cmd, R14, DTRREQ | BRSRC);
-  }
-
-  /* Configure clocks */
-  if (info->type == TYPE_TWIN) {
-    /* Disable external TX clock receiver */
-    outb_p((info->twin_serial_cfg &=
-	    ~(priv->channel ? TWIN_EXTCLKB : TWIN_EXTCLKA)), 
-	   io + TWIN_SERIAL_CFG);
-  }
-  write_scc(cmd, R11, priv->param.clocks);
-  if ((info->type == TYPE_TWIN) && !(priv->param.clocks & TRxCOI)) {
-    /* Enable external TX clock receiver */
-    outb_p((info->twin_serial_cfg |=
-	    (priv->channel ? TWIN_EXTCLKB : TWIN_EXTCLKA)),
-	   io + TWIN_SERIAL_CFG);
-  }
-
-  /* Configure PackeTwin */
-  if (info->type == TYPE_TWIN) {
-    /* Assert DTR, enable interrupts */
-    outb_p((info->twin_serial_cfg |= TWIN_EI |
-	    (priv->channel ? TWIN_DTRB_ON : TWIN_DTRA_ON)),
-	   io + TWIN_SERIAL_CFG);
-  }
-
-  /* Read current status */
-  priv->status = read_scc(cmd, R0);
-  /* Enable SYNC, DCD, and CTS interrupts */
-  write_scc(cmd, R15, DCDIE | CTSIE | SYNCIE);
-
-  /* Configure PI2 DMA */
-  if (info->type <= TYPE_PI2) outb_p(1, io + PI_DREQ_MASK);
-
-  dev->start = 1;
-  info->open++;
-  MOD_INC_USE_COUNT;
-
-  return 0;
-}
-
-
-static int scc_close(struct device *dev)
-{
-  struct scc_priv *priv = dev->priv;
-  struct scc_info *info = priv->info;
-  int io = dev->base_addr;
-  int cmd = priv->cmd;
-
-  dev->start = 0;
-  info->open--;
-  MOD_DEC_USE_COUNT;
-
-  if (info->type == TYPE_TWIN)
-    /* Drop DTR */
-    outb_p((info->twin_serial_cfg &=
-	    (priv->channel ? ~TWIN_DTRB_ON : ~TWIN_DTRA_ON)),
-	   io + TWIN_SERIAL_CFG);
-
-  /* Reset channel, free DMA */
-  write_scc(cmd, R9, (priv->channel ? CHRB : CHRA) | MIE | NV);
-  if (dev->dma) {
-    if (info->type == TYPE_TWIN) outb_p(0, io + TWIN_DMA_CFG);
-    free_dma(dev->dma);
-  }
-
-  if (!info->open) {
-    if (info->type <= TYPE_PI2) outb_p(0, io + PI_DREQ_MASK);
-    free_irq(dev->irq, info);
-  }
-  return 0;
-}
-
-
-static int scc_ioctl(struct device *dev, struct ifreq *ifr, int cmd)
-{
-  int rc;
-  struct scc_priv *priv = dev->priv;
-  
-  switch (cmd) {
-  case SIOCGSCCPARAM:
-    rc = verify_area(VERIFY_WRITE, ifr->ifr_data, sizeof(struct scc_param));
-    if (rc) return rc;
-    copy_to_user(ifr->ifr_data, &priv->param, sizeof(struct scc_param));
-    return 0;
-  case SIOCSSCCPARAM:
-    if (!suser()) return -EPERM;
-    rc = verify_area(VERIFY_READ, ifr->ifr_data, sizeof(struct scc_param));
-    if (rc) return rc;
-    if (dev->start) return -EAGAIN;
-    copy_from_user(&priv->param, ifr->ifr_data, sizeof(struct scc_param));
-    dev->dma = priv->param.dma;
-    return 0;
-  default:
-    return -EINVAL;
-  }
-}
-
-
-static int scc_send_packet(struct sk_buff *skb, struct device *dev)
-{
-  struct scc_priv *priv = dev->priv;
-  struct scc_info *info = priv->info;
-  int cmd = priv->cmd;
-  unsigned long flags;
-  int i;
-
-  /* Block a timer-based transmit from overlapping */
-  if (test_and_set_bit(0, (void *) &priv->tx_sem) != 0) {
-    atomic_inc((void *) &priv->stats.tx_dropped);
-    dev_kfree_skb(skb, FREE_WRITE);
-    return 0;
-  }
-
-  /* Return with an error if we cannot accept more data */
-  if (dev->tbusy) {
-    priv->tx_sem = 0;
-    return -1;
-  }
-
-  /* Transfer data to DMA buffer */
-  i = priv->tx_head;
-  memcpy(priv->tx_buf[i], skb->data+1, skb->len-1);
-  priv->tx_len[i] = skb->len-1;
-
-  save_flags(flags);
-  cli();
-
-  /* Set the busy flag if we just filled up the last buffer */
-  priv->tx_head = (i + 1) % NUM_TX_BUF;
-  priv->tx_count++;
-  if (priv->tx_count == NUM_TX_BUF) dev->tbusy = 1;
-
-  /* Set new TX state */
-  if (priv->tx_state == TX_IDLE) {
-    /* Assert RTS, start timer */
-    priv->tx_state = TX_TXDELAY;
-    if (info->type <= TYPE_PI2) outb_p(0, dev->base_addr + PI_DREQ_MASK);
-    write_scc(cmd, R5, TxCRC_ENAB | RTS | TxENAB | Tx8);
-    if (info->type <= TYPE_PI2) outb_p(1, dev->base_addr + PI_DREQ_MASK);
-    priv->tx_start = jiffies;
-    delay(dev, priv->param.txdelay);
-  }
-
-  restore_flags(flags);
-
-  dev_kfree_skb(skb, FREE_WRITE);
-
-  priv->tx_sem = 0;
-  return 0;
-}
-
-
-static struct enet_statistics *scc_get_stats(struct device *dev)
-{
-  struct scc_priv *priv = dev->priv;
-
-  return &priv->stats;
-}
-
-
-static int scc_set_mac_address(struct device *dev, void *sa)
-{
-  memcpy(dev->dev_addr, ((struct sockaddr *)sa)->sa_data, dev->addr_len);
-  return 0;
-}
-
-
-static void scc_isr(int irq, void *dev_id, struct pt_regs * regs)
-{
-  struct scc_info *info = dev_id;
-  int is, io = info->dev[0].base_addr;
-
-  /* We're a fast IRQ handler and are called with interrupts disabled */
-
-  /* IRQ sharing doesn't make sense due to ISA's edge-triggered
-     interrupts, hence it is safe to return if we have found and
-     processed a single device. */
-
-  /* Interrupt processing: We loop until we know that the IRQ line is
-     low. If another positive edge occurs afterwards during the ISR,
-     another interrupt will be triggered by the interrupt controller
-     as soon as the IRQ level is enabled again (see asm/irq.h). */
-
-  switch (info->type) {
-  case TYPE_PI:
-  case TYPE_PI2:
-    outb_p(0, io + PI_DREQ_MASK);
-    z8530_isr(info);
-    outb_p(1, io + PI_DREQ_MASK);
-    return;
-  case TYPE_TWIN:
-    while ((is = ~inb_p(io + TWIN_INT_REG)) &
-	   TWIN_INT_MSK) {
-      if (is & TWIN_SCC_MSK) {
-	z8530_isr(info);
-      } else if (is & TWIN_TMR1_MSK) {
-	inb_p(io + TWIN_CLR_TMR1);
-	tm_isr(&info->dev[0]);
-      } else {
-	inb_p(io + TWIN_CLR_TMR2);
-	tm_isr(&info->dev[1]);
-      }
-    }
-    /* No interrupts pending from the PackeTwin */
-    return;
-  }
-}
-
-
-static inline void z8530_isr(struct scc_info *info)
-{
-  int is, a_cmd;
-  
-  a_cmd = info->scc_base + SCCA_CMD;
-
-  while ((is = read_scc(a_cmd, R3))) {
-    if (is & CHARxIP) {
-      rx_isr(&info->dev[0]);
-    } else if (is & CHATxIP) {
-      tx_isr(&info->dev[0]);
-    } else if (is & CHAEXT) {
-      es_isr(&info->dev[0]);
-    } else if (is & CHBRxIP) {
-      rx_isr(&info->dev[1]);
-    } else if (is & CHBTxIP) {
-      tx_isr(&info->dev[1]);
-    } else {
-      es_isr(&info->dev[1]);
-    }
-  }
-  /* Ok, no interrupts pending from this 8530. The INT line should
-     be inactive now. */
-}
-
-
-static void rx_isr(struct device *dev)
-{
-  struct scc_priv *priv = dev->priv;
-  int cmd = priv->cmd;
-
-  if (dev->dma) {
-    /* Check special condition and perform error reset. See 2.4.7.5. */
-    special_condition(dev, read_scc(cmd, R1));
-    write_scc(cmd, R0, ERR_RES);
-  } else {
-    /* Check special condition for each character. Error reset not necessary.
-       Same algorithm for SCC and ESCC. See 2.4.7.1 and 2.4.7.4. */
-    int rc;
-    while (read_scc(cmd, R0) & Rx_CH_AV) {
-      rc = read_scc(cmd, R1);
-      if (priv->rx_ptr < BUF_SIZE)
-	priv->rx_buf[priv->rx_head][priv->rx_ptr++] = read_scc(cmd, R8);
-      else {
-	priv->rx_over = 2;
-	read_scc(cmd, R8);
-      }
-      special_condition(dev, rc);
-    }
-  }
-}
-
-
-static void special_condition(struct device *dev, int rc)
-{
-  struct scc_priv *priv = dev->priv;
-  int cb, cmd = priv->cmd;
-
-  /* See Figure 2-15. Only overrun and EOF need to be checked. */
-  
-  if (rc & Rx_OVR) {
-    /* Receiver overrun */
-    priv->rx_over = 1;
-    if (!dev->dma) write_scc(cmd, R0, ERR_RES);
-  } else if (rc & END_FR) {
-    /* End of frame. Get byte count */
-    if (dev->dma) {
-	disable_dma(dev->dma);
-	clear_dma_ff(dev->dma);
-	cb = BUF_SIZE - get_dma_residue(dev->dma) - 2;
-    } else {
-	cb = priv->rx_ptr - 2;
-    }
-    if (priv->rx_over) {
-      /* We had an overrun */
-      priv->stats.rx_errors++;
-      if (priv->rx_over == 2) priv->stats.rx_length_errors++;
-      else priv->stats.rx_fifo_errors++;
-      priv->rx_over = 0;
-    } else if (rc & CRC_ERR) {
-      /* Count invalid CRC only if packet length >= minimum */
-      if (cb >= 8) {
-	priv->stats.rx_errors++;
-	priv->stats.rx_crc_errors++;
-      }
-    } else {
-      if (cb >= 8) {
-	/* Put good frame in FIFO */
-	priv->rx_len[priv->rx_head] = cb;
-	priv->rx_head = (priv->rx_head + 1) % NUM_RX_BUF;
-	priv->rx_count++;
-	if (priv->rx_count == NUM_RX_BUF) {
-	  /* Disable receiver if FIFO full */
-	  write_scc(cmd, R3, Rx8);
-	  priv->stats.rx_errors++;
-	  priv->stats.rx_over_errors++;
-	}
-	/* Mark bottom half handler */
-	queue_task(&priv->rx_task, &tq_immediate);
-	mark_bh(IMMEDIATE_BH);
-      }
-    }
-    /* Get ready for new frame */
-    if (dev->dma) {
-      set_dma_addr(dev->dma, (int) priv->rx_buf[priv->rx_head]);
-      set_dma_count(dev->dma, BUF_SIZE);
-      enable_dma(dev->dma);
-    } else {
-      priv->rx_ptr = 0;
-    }
-  }
-}
-
-
-static void rx_bh(void *arg)
-{
-  struct device *dev = arg;
-  struct scc_priv *priv = dev->priv;
-  struct scc_info *info = priv->info;
-  int cmd = priv->cmd;
-  int i = priv->rx_tail;
-  int cb;
-  unsigned long flags;
-  struct sk_buff *skb;
-  unsigned char *data;
-
-  save_flags(flags);
-  cli();
-
-  while (priv->rx_count) {
-    restore_flags(flags);
-    cb = priv->rx_len[i];
-    /* Allocate buffer */
-    skb = dev_alloc_skb(cb+1);
-    if (skb == NULL) {
-      /* Drop packet */
-      priv->stats.rx_dropped++;
-    } else {
-      /* Fill buffer */
-      data = skb_put(skb, cb+1);
-      data[0] = 0;
-      memcpy(&data[1], priv->rx_buf[i], cb);
-      skb->dev = dev;
-      skb->protocol = ntohs(ETH_P_AX25);
-      skb->mac.raw = skb->data;
-      netif_rx(skb);
-      priv->stats.rx_packets++;
-    }
-    save_flags(flags);
-    cli();
-    /* Enable receiver if RX buffers have been unavailable */
-    if ((priv->rx_count == NUM_RX_BUF) && (priv->status & DCD)) {
-      if (info->type <= TYPE_PI2) outb_p(0, dev->base_addr + PI_DREQ_MASK);
-      write_scc(cmd, R3, RxENABLE | Rx8 | RxCRC_ENAB);
-      if (info->type <= TYPE_PI2) outb_p(1, dev->base_addr + PI_DREQ_MASK);
-    }
-    /* Move tail */
-    priv->rx_tail = i = (i + 1) % NUM_RX_BUF;
-    priv->rx_count--;
-  }
-
-  restore_flags(flags);
-}
-
-
-static void tx_isr(struct device *dev)
-{
-  struct scc_priv *priv = dev->priv;
-  int cmd = priv->cmd;
-  int i = priv->tx_tail, p = priv->tx_ptr;
-
-  /* Suspend TX interrupts if we don't want to send anything.
-     See Figure 2-22. */
-  if (p ==  priv->tx_len[i]) {
-    write_scc(cmd, R0, RES_Tx_P);
-    return;
-  }
-
-  /* Write characters */
-  while ((read_scc(cmd, R0) & Tx_BUF_EMP) && p < priv->tx_len[i]) {
-    write_scc(cmd, R8, priv->tx_buf[i][p++]);
-  }
-  priv->tx_ptr = p;
-
-}
-
-
-static void es_isr(struct device *dev)
-{
-  struct scc_priv *priv = dev->priv;
-  struct scc_info *info = priv->info;
-  int i, cmd = priv->cmd;
-  int st, dst, res;
-
-  /* Read status and reset interrupt bit */
-  st = read_scc(cmd, R0);
-  write_scc(cmd, R0, RES_EXT_INT);
-  dst = priv->status ^ st;
-  priv->status = st;
-
-  /* Since the EOM latch is reset automatically, we assume that
-     it has been zero if and only if we are in the TX_ACTIVE state.
-     Otherwise we follow 2.4.9.6. */
-
-  /* Transmit underrun */
-  if ((priv->tx_state == TX_ACTIVE) && (st & TxEOM)) {
-    /* Get remaining bytes */
-    i = priv->tx_tail;
-    if (dev->dma) {
-      disable_dma(dev->dma);
-      clear_dma_ff(dev->dma);
-      res = get_dma_residue(dev->dma);
-    } else {
-      res = priv->tx_len[i] - priv->tx_ptr;
-      if (res) write_scc(cmd, R0, RES_Tx_P);
-      priv->tx_ptr = 0;
-    }
-    /* Remove frame from FIFO */
-    priv->tx_tail = (i + 1) % NUM_TX_BUF;
-    priv->tx_count--;
-    dev->tbusy = 0;
-    /* Check if another frame is available and we are allowed to transmit */
-    if (priv->tx_count && (jiffies - priv->tx_start) < priv->param.txtime) {
-      if (dev->dma) {
-	set_dma_addr(dev->dma, (int) priv->tx_buf[priv->tx_tail]);
-	set_dma_count(dev->dma, priv->tx_len[priv->tx_tail]);
-	enable_dma(dev->dma);
-      } else {
-	/* If we have an ESCC, we are allowed to write data bytes
-	   immediately. Otherwise we have to wait for the next
-	   TX interrupt. See Figure 2-22. */
-	if (info->chip == Z85230) {
-	  tx_isr(dev);
-	}
-      }
-    } else {
-      /* No frame available. Disable interrupts. */
-      priv->tx_state = TX_SQDELAY;
-      delay(dev, priv->param.sqdelay);
-      write_scc(cmd, R15, DCDIE | CTSIE | SYNCIE);
-      write_scc(cmd, R1, EXT_INT_ENAB | WT_FN_RDYFN);
-    }
-    /* Update packet statistics */
-    if (res) {
-      priv->stats.tx_errors++;
-      priv->stats.tx_fifo_errors++;
-    } else {
-      priv->stats.tx_packets++;
-    }
-    /* Inform upper layers */
-    mark_bh(NET_BH);
-  }
-
-  /* DCD transition */
-  if ((priv->tx_state < TX_TXDELAY) && (dst & DCD)) {
-    /* Transmitter state change */
-    priv->tx_state = TX_OFF;
-    /* Enable or disable receiver */
-    if (st & DCD) {
-      if (dev->dma) {
-	/* Program DMA controller */
-	disable_dma(dev->dma);
-	clear_dma_ff(dev->dma);
-	set_dma_mode(dev->dma, DMA_MODE_READ);
-	set_dma_addr(dev->dma, (int) priv->rx_buf[priv->rx_head]);
-	set_dma_count(dev->dma, BUF_SIZE);
-	enable_dma(dev->dma);
-	/* Configure PackeTwin DMA */
-	if (info->type == TYPE_TWIN) {
-	  outb_p((dev->dma == 1) ? TWIN_DMA_HDX_R1 : TWIN_DMA_HDX_R3,
-		 dev->base_addr + TWIN_DMA_CFG);
-	}
-	/* Sp. cond. intr. only, ext int enable */
-	write_scc(cmd, R1, EXT_INT_ENAB | INT_ERR_Rx |
-		  WT_RDY_RT | WT_FN_RDYFN | WT_RDY_ENAB);
-      } else {
-	/* Intr. on all Rx characters and Sp. cond., ext int enable */
-	write_scc(cmd, R1, EXT_INT_ENAB | INT_ALL_Rx | WT_RDY_RT |
-		  WT_FN_RDYFN);
-      }
-      if (priv->rx_count < NUM_RX_BUF) {
-	/* Enable receiver */
-	write_scc(cmd, R3, RxENABLE | Rx8 | RxCRC_ENAB);
-      }
-    } else {
-      /* Disable DMA */
-      if (dev->dma) disable_dma(dev->dma);
-      /* Disable receiver */
-      write_scc(cmd, R3, Rx8);
-      /* DMA disable, RX int disable, Ext int enable */
-      write_scc(cmd, R1, EXT_INT_ENAB | WT_RDY_RT | WT_FN_RDYFN);
-      /* Transmitter state change */
-      if (random() > priv->param.persist)
-	delay(dev, priv->param.slottime);
-      else {
-	if (priv->tx_count) {
-	  priv->tx_state = TX_TXDELAY;
-	  write_scc(cmd, R5, TxCRC_ENAB | RTS | TxENAB | Tx8);
-	  priv->tx_start = jiffies;
-	  delay(dev, priv->param.txdelay);
-	} else {
-	  priv->tx_state = TX_IDLE;
-	}
-      }
-    }
-  }
-
-  /* CTS transition */
-  if ((info->type <= TYPE_PI2) && (dst & CTS) && (~st & CTS)) {
-    /* Timer has expired */
-    tm_isr(dev);
-  }
-
-  /* /SYNC/HUNT transition */
-  if ((dst & SYNC_HUNT) && (~st & SYNC_HUNT)) {
-    /* Reset current frame and clear RX FIFO */
-    while (read_scc(cmd, R0) & Rx_CH_AV) read_scc(cmd, R8);
-    priv->rx_over = 0;
-    if (dev->dma) {
-      disable_dma(dev->dma);
-      clear_dma_ff(dev->dma);
-      set_dma_addr(dev->dma, (int) priv->rx_buf[priv->rx_head]);
-      set_dma_count(dev->dma, BUF_SIZE);
-      enable_dma(dev->dma);
-    } else {
-      priv->rx_ptr = 0;
-    }
-  }
-}
-
-
-static void tm_isr(struct device *dev)
-{
-  struct scc_priv *priv = dev->priv;
-  struct scc_info *info = priv->info;
-  int cmd = priv->cmd;
-
-  switch (priv->tx_state) {
-  case TX_OFF:
-    if (~priv->status & DCD) {
-      if (random() > priv->param.persist) delay(dev, priv->param.slottime);
-      else {
-	if (priv->tx_count) {
-	  priv->tx_state = TX_TXDELAY;
-	  write_scc(cmd, R5, TxCRC_ENAB | RTS | TxENAB | Tx8);
-	  priv->tx_start = jiffies;
-	  delay(dev, priv->param.txdelay);
-	} else {
-	  priv->tx_state = TX_IDLE;
-	}
-      }
-    }
-    break;
-  case TX_TXDELAY:
-    priv->tx_state = TX_ACTIVE;
-    if (dev->dma) {
-      /* Program DMA controller */
-      disable_dma(dev->dma);
-      clear_dma_ff(dev->dma);
-      set_dma_mode(dev->dma, DMA_MODE_WRITE);
-      set_dma_addr(dev->dma, (int) priv->tx_buf[priv->tx_tail]);
-      set_dma_count(dev->dma, priv->tx_len[priv->tx_tail]);
-      enable_dma(dev->dma);
-      /* Configure PackeTwin DMA */
-      if (info->type == TYPE_TWIN) {
-	outb_p((dev->dma == 1) ? TWIN_DMA_HDX_T1 : TWIN_DMA_HDX_T3,
-	       dev->base_addr + TWIN_DMA_CFG);
-      }
-      /* Enable interrupts and DMA. On the PackeTwin, the DTR//REQ pin
-	 is used for TX DMA requests, but we enable the WAIT/DMA request
-	 pin, anyway */
-      write_scc(cmd, R15, TxUIE | DCDIE | CTSIE | SYNCIE);
-      write_scc(cmd, R1, EXT_INT_ENAB | WT_FN_RDYFN | WT_RDY_ENAB);
-    } else {
-      write_scc(cmd, R15, TxUIE | DCDIE | CTSIE | SYNCIE);
-      write_scc(cmd, R1, EXT_INT_ENAB | WT_FN_RDYFN | TxINT_ENAB);
-      tx_isr(dev);
-    }
-    if (info->chip == Z8530) write_scc(cmd, R0, RES_EOM_L);
-    break;
-  case TX_SQDELAY:
-    /* Disable transmitter */
-    write_scc(cmd, R5, TxCRC_ENAB | Tx8);
-    /* Transmitter state change: Switch to TX_OFF and wait at least
-       1 slottime. */
-    priv->tx_state = TX_OFF;    
-    if (~priv->status & DCD) delay(dev, priv->param.waittime);
-  }
-}
-
-
-static inline void delay(struct device *dev, int t)
-{
-  struct scc_priv *priv = dev->priv;
-  int tmr = priv->tmr;
-
-  outb_p(t & 0xFF, tmr);
-  outb_p((t >> 8) & 0xFF, tmr);
-}
-
-
-static inline unsigned char random(void)
-{
-  /* See "Numerical Recipes in C", second edition, p. 284 */
-  rand = rand * 1664525L + 1013904223L;
-  return (unsigned char) (rand >> 24);
-}
-
-

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov