Cache fixes, part #1.

1 files changed, 0 insertions, 2019 deletions

diff --git a/drivers/sgi/char/sgiserial.c b/drivers/sgi/char/sgiserial.c
index b6a3effc6..c8d4d7e54 100644
--- a/drivers/sgi/char/sgiserial.c
+++ b/drivers/sgi/char/sgiserial.c
@@ -1601,2025 +1601,6 @@ static int block_til_ready(struct tty_struct *tty, struct file * filp,
 		if (!(info->flags & ZILOG_CALLOUT_ACTIVE) &&
 		    !(info->flags & ZILOG_CLOSING) && do_clocal)
 			break;
-		if (current->signal & ~current->blocked) {
-			retval = -ERESTARTSYS;
-			break;
-		}
-#ifdef SERIAL_DEBUG_OPEN
-		printk("block_til_ready blocking: ttys%d, count = %d\n",
-		       info->line, info->count);
-#endif
-		schedule();
-	}
-	current->state = TASK_RUNNING;
-	remove_wait_queue(&info->open_wait, &wait);
-	if (!tty_hung_up_p(filp))
-		info->count++;
-	info->blocked_open--;
-#ifdef SERIAL_DEBUG_OPEN
-	printk("block_til_ready after blocking: ttys%d, count = %d\n",
-	       info->line, info->count);
-#endif
-	if (retval)
-		return retval;
-	info->flags |= ZILOG_NORMAL_ACTIVE;
-	return 0;
-}	
-
-/*
- * This routine is called whenever a serial port is opened.  It
- * enables interrupts for a serial port, linking in its ZILOG structure into
- * the IRQ chain.   It also performs the serial-specific
- * initialization for the tty structure.
- */
-int rs_open(struct tty_struct *tty, struct file * filp)
-{
-	struct sgi_serial	*info;
-	int 			retval, line;
-
-	line = MINOR(tty->device) - tty->driver.minor_start;
-	/* The zilog lines for the mouse/keyboard must be
-	 * opened using their respective drivers.
-	 */
-	if ((line < 0) || (line >= NUM_CHANNELS))
-		return -ENODEV;
-	info = zs_soft + line;
-	/* Is the kgdb running over this line? */
-	if (info->kgdb_channel)
-		return -ENODEV;
-	if (serial_paranoia_check(info, tty->device, "rs_open"))
-		return -ENODEV;
-#ifdef SERIAL_DEBUG_OPEN
-	printk("rs_open %s%d, count = %d\n", tty->driver.name, info->line,
-	       info->count);
-#endif
-	info->count++;
-	tty->driver_data = info;
-	info->tty = tty;
-
-	/*
-	 * Start up serial port
-	 */
-	retval = startup(info);
-	if (retval)
-		return retval;
-
-	retval = block_til_ready(tty, filp, info);
-	if (retval) {
-#ifdef SERIAL_DEBUG_OPEN
-		printk("rs_open returning after block_til_ready with %d\n",
-		       retval);
-#endif
-		return retval;
-	}
-
-	if ((info->count == 1) && (info->flags & ZILOG_SPLIT_TERMIOS)) {
-		if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
-			*tty->termios = info->normal_termios;
-		else 
-			*tty->termios = info->callout_termios;
-		change_speed(info);
-	}
-
-	info->session = current->session;
-	info->pgrp = current->pgrp;
-
-#ifdef SERIAL_DEBUG_OPEN
-	printk("rs_open ttys%d successful...", info->line);
-#endif
-	return 0;
-}
-
-/* Finally, routines used to initialize the serial driver. */
-
-static void show_serial_version(void)
-{
-	printk("SGI Zilog8530 serial driver version 1.00\n");
-}
-
-/* Return layout for the requested zs chip number. */
-static inline struct sgi_zslayout *get_zs(int chip)
-{
-	extern struct hpc3_miscregs *hpc3mregs;
-
-	if(chip > 0) {
-		prom_printf("Wheee, bogus zs chip number requested.\n");
-		prom_getchar();
-		romvec->imode();
-	}
-	return (struct sgi_zslayout *) (&hpc3mregs->ser1cmd);
-
-}
-
-extern void register_console(void (*proc)(const char *));
-
-static inline void
-rs_cons_check(struct sgi_serial *ss, int channel)
-{
-	int i, o, io;
-	static consout_registered = 0;
-	static msg_printed = 0;
-
-	i = o = io = 0;
-
-	/* Is this one of the serial console lines? */
-	if((zs_cons_chanout != channel) &&
-	   (zs_cons_chanin != channel))
-		return;
-	zs_conschan = ss->zs_channel;
-	zs_consinfo = ss;
-
-	/* Register the console output putchar, if necessary */
-	if((zs_cons_chanout == channel)) {
-		o = 1;
-		/* double whee.. */
-		if(!consout_registered) {
-			register_console(zs_console_print);
-			consout_registered = 1;
-		}
-	}
-
-	/* If this is console input, we handle the break received
-	 * status interrupt on this line to mean prom_halt().
-	 */
-	if(zs_cons_chanin == channel) {
-		ss->break_abort = 1;
-		i = 1;
-	}
-	if(o && i)
-		io = 1;
-	if(ss->zs_baud != 9562) { /* Don't ask... */
-		prom_printf("BAD console baud rate %d\n", ss->zs_baud);
-		prom_getchar();
-		prom_imode();
-		panic("Console baud rate weirdness");
-	}
-
-	/* Set flag variable for this port so that it cannot be
-	 * opened for other uses by accident.
-	 */
-	ss->is_cons = 1;
-
-	if(io) {
-		if(!msg_printed) {
-			printk("zs%d: console I/O\n", ((channel>>1)&1));
-			msg_printed = 1;
-		}
-	} else {
-		printk("zs%d: console %s\n", ((channel>>1)&1),
-		       (i==1 ? "input" : (o==1 ? "output" : "WEIRD")));
-	}
-}
-
-volatile int test_done;
-
-/* rs_init inits the driver */
-int rs_init(void)
-{
-	int chip, channel, i, flags;
-	struct sgi_serial *info;
-
-	/* Setup base handler, and timer table. */
-	init_bh(SERIAL_BH, do_serial_bh);
-	timer_table[RS_TIMER].fn = rs_timer;
-	timer_table[RS_TIMER].expires = 0;
-
-	show_serial_version();
-
-	/* Initialize the tty_driver structure */
-	/* SGI: Not all of this is exactly right for us. */
-	
-	memset(&serial_driver, 0, sizeof(struct tty_driver));
-	serial_driver.magic = TTY_DRIVER_MAGIC;
-	serial_driver.name = "ttyS";
-	serial_driver.major = TTY_MAJOR;
-	serial_driver.minor_start = 64;
-	serial_driver.num = NUM_CHANNELS;
-	serial_driver.type = TTY_DRIVER_TYPE_SERIAL;
-	serial_driver.subtype = SERIAL_TYPE_NORMAL;
-	serial_driver.init_termios = tty_std_termios;
-
-	serial_driver.init_termios.c_cflag =
-		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
-	serial_driver.flags = TTY_DRIVER_REAL_RAW;
-	serial_driver.refcount = &serial_refcount;
-	serial_driver.table = serial_table;
-	serial_driver.termios = serial_termios;
-	serial_driver.termios_locked = serial_termios_locked;
-
-	serial_driver.open = rs_open;
-	serial_driver.close = rs_close;
-	serial_driver.write = rs_write;
-	serial_driver.flush_chars = rs_flush_chars;
-	serial_driver.write_room = rs_write_room;
-	serial_driver.chars_in_buffer = rs_chars_in_buffer;
-	serial_driver.flush_buffer = rs_flush_buffer;
-	serial_driver.ioctl = rs_ioctl;
-	serial_driver.throttle = rs_throttle;
-	serial_driver.unthrottle = rs_unthrottle;
-	serial_driver.set_termios = rs_set_termios;
-	serial_driver.stop = rs_stop;
-	serial_driver.start = rs_start;
-	serial_driver.hangup = rs_hangup;
-
-	/*
-	 * The callout device is just like normal device except for
-	 * major number and the subtype code.
-	 */
-	callout_driver = serial_driver;
-	callout_driver.name = "cua";
-	callout_driver.major = TTYAUX_MAJOR;
-	callout_driver.subtype = SERIAL_TYPE_CALLOUT;
-
-	if (tty_register_driver(&serial_driver))
-		panic("Couldn't register serial driver\n");
-	if (tty_register_driver(&callout_driver))
-		panic("Couldn't register callout driver\n");
-	
-	save_flags(flags); cli();
-
-	/* Set up our interrupt linked list */
-	zs_chain = &zs_soft[0];
-	zs_soft[0].zs_next = &zs_soft[1];
-	zs_soft[1].zs_next = 0;
-
-	for(chip = 0; chip < NUM_SERIAL; chip++) {
-		/* If we are doing kgdb over one of the channels on
-		 * chip zero, kgdb_channel will be set to 1 by the
-		 * rs_kgdb_hook() routine below.
-		 */
-		if(!zs_chips[chip]) {
-			zs_chips[chip] = get_zs(chip);
-			/* Two channels per chip */
-			zs_channels[(chip*2)] = &zs_chips[chip]->channelA;
-			zs_channels[(chip*2)+1] = &zs_chips[chip]->channelB;
-			zs_soft[(chip*2)].kgdb_channel = 0;
-			zs_soft[(chip*2)+1].kgdb_channel = 0;
-		}
-		/* First, set up channel A on this chip. */
-		channel = chip * 2;
-		zs_soft[channel].zs_channel = zs_channels[channel];
-		zs_soft[channel].change_needed = 0;
-		zs_soft[channel].clk_divisor = 16;
-		zs_soft[channel].zs_baud = get_zsbaud(&zs_soft[channel]);
-		zs_soft[channel].cons_mouse = 0;
-		/* If not keyboard/mouse and is console serial
-		 * line, then enable receiver interrupts.
-		 */
-		if(zs_soft[channel].is_cons) {
-			write_zsreg(zs_soft[channel].zs_channel, R1,
-				    (EXT_INT_ENAB | INT_ALL_Rx));
-			write_zsreg(zs_soft[channel].zs_channel, R9, (NV | MIE));
-			write_zsreg(zs_soft[channel].zs_channel, R10, (NRZ));
-			write_zsreg(zs_soft[channel].zs_channel, R3, (Rx8|RxENABLE));
-			write_zsreg(zs_soft[channel].zs_channel, R5, (Tx8 | TxENAB));
-		}
-		/* If this is the kgdb line, enable interrupts because we
-		 * now want to receive the 'control-c' character from the
-		 * client attached to us asynchronously.
-		 */
-		if(zs_soft[channel].kgdb_channel)
-			kgdb_chaninit(&zs_soft[channel], 1,
-				      zs_soft[channel].zs_baud);
-
-		/* Now, channel B */
-		channel++;
-		zs_soft[channel].zs_channel = zs_channels[channel];
-		zs_soft[channel].change_needed = 0;
-		zs_soft[channel].clk_divisor = 16;
-		zs_soft[channel].zs_baud = get_zsbaud(&zs_soft[channel]);
-		zs_soft[channel].cons_keyb = 0;
-		/* If console serial line, then enable receiver interrupts. */
-		if(zs_soft[channel].is_cons) {
-			write_zsreg(zs_soft[channel].zs_channel, R1,
-				    (EXT_INT_ENAB | INT_ALL_Rx));
-			write_zsreg(zs_soft[channel].zs_channel, R9,
-				    (NV | MIE));
-			write_zsreg(zs_soft[channel].zs_channel, R10,
-				    (NRZ));
-			write_zsreg(zs_soft[channel].zs_channel, R3,
-				    (Rx8|RxENABLE));
-			write_zsreg(zs_soft[channel].zs_channel, R5,
-				    (Tx8 | TxENAB | RTS | DTR));
-		}
-	}
-
-	for(info=zs_chain, i=0; info; info = info->zs_next, i++)
-	{
-		info->magic = SERIAL_MAGIC;
-		info->port = (int) info->zs_channel;
-		info->line = i;
-		info->tty = 0;
-		info->irq = zilog_irq;
-		info->custom_divisor = 16;
-		info->close_delay = 50;
-		info->closing_wait = 3000;
-		info->x_char = 0;
-		info->event = 0;
-		info->count = 0;
-		info->blocked_open = 0;
-		info->tqueue.routine = do_softint;
-		info->tqueue.data = info;
-		info->tqueue_hangup.routine = do_serial_hangup;
-		info->tqueue_hangup.data = info;
-		info->callout_termios =callout_driver.init_termios;
-		info->normal_termios = serial_driver.init_termios;
-		info->open_wait = 0;
-		info->close_wait = 0;
-		printk("tty%02d at 0x%04x (irq = %d)", info->line, 
-		       info->port, info->irq);
-		printk(" is a Zilog8530\n");
-	}
-
-	if (request_irq(zilog_irq, rs_interrupt, (SA_INTERRUPT),
-			"Zilog8530", zs_chain))
-		panic("Unable to attach zs intr\n");
-	restore_flags(flags);
-
-	return 0;
-}
-
-/*
- * register_serial and unregister_serial allows for serial ports to be
- * configured at run-time, to support PCMCIA modems.
- */
-/* SGI: Unused at this time, just here to make things link. */
-int register_serial(struct serial_struct *req)
-{
-	return -1;
-}
-
-void unregister_serial(int line)
-{
-	return;
-}
-
-/* Hooks for running a serial console.  con_init() calls this if the
- * console is being run over one of the ttya/ttyb serial ports.
- * 'chip' should be zero, as chip 1 drives the mouse/keyboard.
- * 'channel' is decoded as 0=TTYA 1=TTYB, note that the channels
- * are addressed backwards, channel B is first, then channel A.
- */
-void
-rs_cons_hook(int chip, int out, int line)
-{
-	int channel;
-
-	if(chip)
-		panic("rs_cons_hook called with chip not zero");
-	if(line != 1 && line != 2)
-		panic("rs_cons_hook called with line not ttya or ttyb");
-	channel = line - 1;
-	if(!zs_chips[chip]) {
-		zs_chips[chip] = get_zs(chip);
-		/* Two channels per chip */
-		zs_channels[(chip*2)] = &zs_chips[chip]->channelA;
-		zs_channels[(chip*2)+1] = &zs_chips[chip]->channelB;
-	}
-	zs_soft[channel].zs_channel = zs_channels[channel];
-	zs_soft[channel].change_needed = 0;
-	zs_soft[channel].clk_divisor = 16;
-	zs_soft[channel].zs_baud = get_zsbaud(&zs_soft[channel]);
-	if(out)
-		zs_cons_chanout = ((chip * 2) + channel);
-	else
-		zs_cons_chanin = ((chip * 2) + channel);
-	rs_cons_check(&zs_soft[channel], channel);
-}
-
-/* This is called at boot time to prime the kgdb serial debugging
- * serial line.  The 'tty_num' argument is 0 for /dev/ttyd2 and 1 for
- * /dev/ttyd1 (yes they are backwards on purpose) which is determined
- * in setup_arch() from the boot command line flags.
- */
-void
-rs_kgdb_hook(int tty_num)
-{
-	int chip = 0;
-
-	if(!zs_chips[chip]) {
-		zs_chips[chip] = get_zs(chip);
-		/* Two channels per chip */
-		zs_channels[(chip*2)] = &zs_chips[chip]->channelA;
-		zs_channels[(chip*2)+1] = &zs_chips[chip]->channelB;
-	}
-	zs_soft[tty_num].zs_channel = zs_channels[tty_num];
-	zs_kgdbchan = zs_soft[tty_num].zs_channel;
-	zs_soft[tty_num].change_needed = 0;
-	zs_soft[tty_num].clk_divisor = 16;
-	zs_soft[tty_num].zs_baud = get_zsbaud(&zs_soft[tty_num]);
-	zs_soft[tty_num].kgdb_channel = 1;     /* This runs kgdb */
-	zs_soft[tty_num ^ 1].kgdb_channel = 0; /* This does not */
-
-	/* Turn on transmitter/receiver at 8-bits/char */
-	kgdb_chaninit(&zs_soft[tty_num], 0, 9600);
-	ZS_CLEARERR(zs_kgdbchan);
-	udelay(5);
-	ZS_CLEARFIFO(zs_kgdbchan);
-}
-/* sgiserial.c: Serial port driver for SGI machines.
- *
- * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
- */
-
-#include <linux/errno.h>
-#include <linux/signal.h>
-#include <linux/sched.h>
-#include <linux/timer.h>
-#include <linux/interrupt.h>
-#include <linux/tty.h>
-#include <linux/tty_flip.h>
-#include <linux/major.h>
-#include <linux/string.h>
-#include <linux/fcntl.h>
-#include <linux/mm.h>
-#include <linux/kernel.h>
-#include <linux/delay.h>
-
-#include <asm/io.h>
-#include <asm/irq.h>
-#include <asm/sgialib.h>
-#include <asm/system.h>
-#include <asm/bitops.h>
-#include <asm/sgihpc.h>
-#include <asm/sgint23.h>
-#include <asm/uaccess.h>
-
-#include "sgiserial.h"
-
-#define NUM_SERIAL 1     /* One chip on board. */
-#define NUM_CHANNELS (NUM_SERIAL * 2)
-
-extern struct wait_queue * keypress_wait;
-
-struct sgi_zslayout *zs_chips[NUM_SERIAL] = { 0, };
-struct sgi_zschannel *zs_channels[NUM_CHANNELS] = { 0, 0, };
-struct sgi_zschannel *zs_conschan;
-struct sgi_zschannel *zs_kgdbchan;
-int zs_nodes[NUM_SERIAL] = { 0, };
-
-struct sgi_serial zs_soft[NUM_CHANNELS];
-struct sgi_serial *zs_chain;  /* IRQ servicing chain */
-static int zilog_irq = 21;
-
-struct tty_struct zs_ttys[NUM_CHANNELS];
-/** struct tty_struct *zs_constty; **/
-
-/* Console hooks... */
-static int zs_cons_chanout = 0;
-static int zs_cons_chanin = 0;
-struct sgi_serial *zs_consinfo = 0;
-
-static unsigned char kgdb_regs[16] = {
-	0, 0, 0,                     /* write 0, 1, 2 */
-	(Rx8 | RxENABLE),            /* write 3 */
-	(X16CLK | SB1 | PAR_EVEN),   /* write 4 */
-	(Tx8 | TxENAB),              /* write 5 */
-	0, 0, 0,                     /* write 6, 7, 8 */
-	(NV),                        /* write 9 */
-	(NRZ),                       /* write 10 */
-	(TCBR | RCBR),               /* write 11 */
-	0, 0,                        /* BRG time constant, write 12 + 13 */
-	(BRENABL),                   /* write 14 */
-	(DCDIE)                      /* write 15 */
-};
-
-#define ZS_CLOCK         3672000   /* Zilog input clock rate */
-
-DECLARE_TASK_QUEUE(tq_serial);
-
-struct tty_driver serial_driver, callout_driver;
-static int serial_refcount;
-
-/* serial subtype definitions */
-#define SERIAL_TYPE_NORMAL	1
-#define SERIAL_TYPE_CALLOUT	2
-  
-/* number of characters left in xmit buffer before we ask for more */
-#define WAKEUP_CHARS 256
-
-/* Debugging... DEBUG_INTR is bad to use when one of the zs
- * lines is your console ;(
- */
-#undef SERIAL_DEBUG_INTR
-#undef SERIAL_DEBUG_OPEN
-#undef SERIAL_DEBUG_FLOW
-
-#define RS_STROBE_TIME 10
-#define RS_ISR_PASS_LIMIT 256
-
-#define _INLINE_ inline
-
-static void change_speed(struct sgi_serial *info);
-
-static struct tty_struct *serial_table[NUM_CHANNELS];
-static struct termios *serial_termios[NUM_CHANNELS];
-static struct termios *serial_termios_locked[NUM_CHANNELS];
-
-#ifndef MIN
-#define MIN(a,b)	((a) < (b) ? (a) : (b))
-#endif
-
-/*
- * tmp_buf is used as a temporary buffer by serial_write.  We need to
- * lock it in case the memcpy_fromfs blocks while swapping in a page,
- * and some other program tries to do a serial write at the same time.
- * Since the lock will only come under contention when the system is
- * swapping and available memory is low, it makes sense to share one
- * buffer across all the serial ports, since it significantly saves
- * memory if large numbers of serial ports are open.
- */
-static unsigned char tmp_buf[4096]; /* This is cheating */
-static struct semaphore tmp_buf_sem = MUTEX;
-
-static inline int serial_paranoia_check(struct sgi_serial *info,
-					dev_t device, const char *routine)
-{
-#ifdef SERIAL_PARANOIA_CHECK
-	static const char *badmagic =
-		"Warning: bad magic number for serial struct (%d, %d) in %s\n";
-	static const char *badinfo =
-		"Warning: null sun_serial for (%d, %d) in %s\n";
-
-	if (!info) {
-		printk(badinfo, MAJOR(device), MINOR(device), routine);
-		return 1;
-	}
-	if (info->magic != SERIAL_MAGIC) {
-		printk(badmagic, MAJOR(device), MINOR(device), routine);
-		return 1;
-	}
-#endif
-	return 0;
-}
-
-/*
- * This is used to figure out the divisor speeds and the timeouts
- */
-static int baud_table[] = {
-	0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
-	9600, 19200, 38400, 57600, 115200, 0 };
-
-/* 
- * Reading and writing Zilog8530 registers.  The delays are to make this
- * driver work on the Sun4 which needs a settling delay after each chip
- * register access, other machines handle this in hardware via auxiliary
- * flip-flops which implement the settle time we do in software.
- */
-static inline unsigned char read_zsreg(struct sgi_zschannel *channel, unsigned char reg)
-{
-	unsigned char retval;
-	volatile unsigned char junk;
-
-	udelay(2);
-	channel->control = reg;
-	junk = ioc_icontrol->istat0;
-	udelay(1);
-	retval = channel->control;
-	return retval;
-}
-
-static inline void write_zsreg(struct sgi_zschannel *channel, unsigned char reg, unsigned char value)
-{
-	volatile unsigned char junk;
-
-	udelay(2);
-	channel->control = reg;
-	junk = ioc_icontrol->istat0;
-	udelay(1);
-	channel->control = value;
-	junk = ioc_icontrol->istat0;
-	return;
-}
-
-static inline void load_zsregs(struct sgi_zschannel *channel, unsigned char *regs)
-{
-	ZS_CLEARERR(channel);
-	ZS_CLEARFIFO(channel);
-	/* Load 'em up */
-	write_zsreg(channel, R4, regs[R4]);
-	write_zsreg(channel, R10, regs[R10]);
-	write_zsreg(channel, R3, regs[R3] & ~RxENABLE);
-	write_zsreg(channel, R5, regs[R5] & ~TxENAB);
-	write_zsreg(channel, R1, regs[R1]);
-	write_zsreg(channel, R9, regs[R9]);
-	write_zsreg(channel, R11, regs[R11]);
-	write_zsreg(channel, R12, regs[R12]);
-	write_zsreg(channel, R13, regs[R13]);
-	write_zsreg(channel, R14, regs[R14]);
-	write_zsreg(channel, R15, regs[R15]);
-	write_zsreg(channel, R3, regs[R3]);
-	write_zsreg(channel, R5, regs[R5]);
-	return;
-}
-
-/* Sets or clears DTR/RTS on the requested line */
-static inline void zs_rtsdtr(struct sgi_serial *ss, int set)
-{
-	if(set) {
-		ss->curregs[5] |= (RTS | DTR);
-		ss->pendregs[5] = ss->curregs[5];
-		write_zsreg(ss->zs_channel, 5, ss->curregs[5]);
-	} else {
-		ss->curregs[5] &= ~(RTS | DTR);
-		ss->pendregs[5] = ss->curregs[5];
-		write_zsreg(ss->zs_channel, 5, ss->curregs[5]);
-	}
-	return;
-}
-
-static inline void kgdb_chaninit(struct sgi_serial *ss, int intson, int bps)
-{
-	int brg;
-
-	if(intson) {
-		kgdb_regs[R1] = INT_ALL_Rx;
-		kgdb_regs[R9] |= MIE;
-	} else {
-		kgdb_regs[R1] = 0;
-		kgdb_regs[R9] &= ~MIE;
-	}
-	brg = BPS_TO_BRG(bps, ZS_CLOCK/16);
-	kgdb_regs[R12] = (brg & 255);
-	kgdb_regs[R13] = ((brg >> 8) & 255);
-	load_zsregs(ss->zs_channel, kgdb_regs);
-}
-
-/* Utility routines for the Zilog */
-static inline int get_zsbaud(struct sgi_serial *ss)
-{
-	struct sgi_zschannel *channel = ss->zs_channel;
-	int brg;
-
-	/* The baud rate is split up between two 8-bit registers in
-	 * what is termed 'BRG time constant' format in my docs for
-	 * the chip, it is a function of the clk rate the chip is
-	 * receiving which happens to be constant.
-	 */
-	brg = ((read_zsreg(channel, 13)&0xff) << 8);
-	brg |= (read_zsreg(channel, 12)&0xff);
-	return BRG_TO_BPS(brg, (ZS_CLOCK/(ss->clk_divisor)));
-}
-
-/*
- * ------------------------------------------------------------
- * rs_stop() and rs_start()
- *
- * This routines are called before setting or resetting tty->stopped.
- * They enable or disable transmitter interrupts, as necessary.
- * ------------------------------------------------------------
- */
-static void rs_stop(struct tty_struct *tty)
-{
-	struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
-	unsigned long flags;
-
-	if (serial_paranoia_check(info, tty->device, "rs_stop"))
-		return;
-	
-	save_flags(flags); cli();
-	if (info->curregs[5] & TxENAB) {
-		info->curregs[5] &= ~TxENAB;
-		info->pendregs[5] &= ~TxENAB;
-		write_zsreg(info->zs_channel, 5, info->curregs[5]);
-	}
-	restore_flags(flags);
-}
-
-static void rs_start(struct tty_struct *tty)
-{
-	struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
-	unsigned long flags;
-	
-	if (serial_paranoia_check(info, tty->device, "rs_start"))
-		return;
-	
-	save_flags(flags); cli();
-	if (info->xmit_cnt && info->xmit_buf && !(info->curregs[5] & TxENAB)) {
-		info->curregs[5] |= TxENAB;
-		info->pendregs[5] = info->curregs[5];
-		write_zsreg(info->zs_channel, 5, info->curregs[5]);
-	}
-	restore_flags(flags);
-}
-
-/* Drop into either the boot monitor or kadb upon receiving a break
- * from keyboard/console input.
- */
-static void batten_down_hatches(void)
-{
-	prom_imode();
-#if 0
-	/* If we are doing kadb, we call the debugger
-	 * else we just drop into the boot monitor.
-	 * Note that we must flush the user windows
-	 * first before giving up control.
-	 */
-	printk("\n");
-	if((((unsigned long)linux_dbvec)>=DEBUG_FIRSTVADDR) &&
-	   (((unsigned long)linux_dbvec)<=DEBUG_LASTVADDR))
-		sp_enter_debugger();
-	else
-		prom_halt();
-
-	/* XXX We want to notify the keyboard driver that all
-	 * XXX keys are in the up state or else weird things
-	 * XXX happen...
-	 */
-#endif
-	return;
-}
-
-/* On receive, this clears errors and the receiver interrupts */
-static inline void rs_recv_clear(struct sgi_zschannel *zsc)
-{
-	volatile unsigned char junk;
-
-	udelay(2);
-	zsc->control = ERR_RES;
-	junk = ioc_icontrol->istat0;
-	udelay(2);
-	zsc->control = RES_H_IUS;
-	junk = ioc_icontrol->istat0;
-}
-
-/*
- * ----------------------------------------------------------------------
- *
- * Here starts the interrupt handling routines.  All of the following
- * subroutines are declared as inline and are folded into
- * rs_interrupt().  They were separated out for readability's sake.
- *
- * Note: rs_interrupt() is a "fast" interrupt, which means that it
- * runs with interrupts turned off.  People who may want to modify
- * rs_interrupt() should try to keep the interrupt handler as fast as
- * possible.  After you are done making modifications, it is not a bad
- * idea to do:
- * 
- * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
- *
- * and look at the resulting assemble code in serial.s.
- *
- * 				- Ted Ts'o (tytso@mit.edu), 7-Mar-93
- * -----------------------------------------------------------------------
- */
-
-/*
- * This routine is used by the interrupt handler to schedule
- * processing in the software interrupt portion of the driver.
- */
-static _INLINE_ void rs_sched_event(struct sgi_serial *info,
-				    int event)
-{
-	info->event |= 1 << event;
-	queue_task(&info->tqueue, &tq_serial);
-	mark_bh(SERIAL_BH);
-}
-
-#ifdef CONFIG_REMOTE_DEBUG
-extern void set_async_breakpoint(unsigned int epc);
-#endif
-
-static _INLINE_ void receive_chars(struct sgi_serial *info, struct pt_regs *regs)
-{
-	struct tty_struct *tty = info->tty;
-	volatile unsigned char junk;
-	unsigned char ch, stat;
-
-	udelay(2);
-	ch = info->zs_channel->data;
-	junk = ioc_icontrol->istat0;
-	udelay(2);
-	stat = read_zsreg(info->zs_channel, R1);
-
-	/* If this is the console keyboard, we need to handle
-	 * L1-A's here.
-	 */
-	if(info->is_cons) {
-		if(ch==0) { /* whee, break received */
-			batten_down_hatches();
-			rs_recv_clear(info->zs_channel);
-			return;
-		} else if (ch == 1) {
-			show_state();
-			return;
-		} else if (ch == 2) {
-			show_buffers();
-			return;
-		}
-		/* It is a 'keyboard interrupt' ;-) */
-		wake_up(&keypress_wait);
-	}
-	/* Look for kgdb 'stop' character, consult the gdb documentation
-	 * for remote target debugging and arch/sparc/kernel/sparc-stub.c
-	 * to see how all this works.
-	 */
-#ifdef CONFIG_REMOTE_DEBUG
-	if((info->kgdb_channel) && (ch =='\003')) {
-		set_async_breakpoint(read_32bit_cp0_register(CP0_EPC));
-		goto clear_and_exit;
-	}
-#endif
-	if(!tty)
-		goto clear_and_exit;
-
-	if (tty->flip.count >= TTY_FLIPBUF_SIZE)
-		queue_task(&tty->flip.tqueue, &tq_timer);
-	tty->flip.count++;
-	if(stat & PAR_ERR)
-		*tty->flip.flag_buf_ptr++ = TTY_PARITY;
-	else if(stat & Rx_OVR)
-		*tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
-	else if(stat & CRC_ERR)
-		*tty->flip.flag_buf_ptr++ = TTY_FRAME;
-	else
-		*tty->flip.flag_buf_ptr++ = 0; /* XXX */
-	*tty->flip.char_buf_ptr++ = ch;
-
-	queue_task(&tty->flip.tqueue, &tq_timer);
-
-clear_and_exit:
-	rs_recv_clear(info->zs_channel);
-	return;
-}
-
-static _INLINE_ void transmit_chars(struct sgi_serial *info)
-{
-	volatile unsigned char junk;
-
-	/* P3: In theory we have to test readiness here because a
-	 * serial console can clog the chip through rs_put_char().
-	 * David did not do this. I think he relies on 3-chars FIFO in 8530.
-	 * Let's watch for lost _output_ characters. XXX
-	 */
-
-	/* SGI ADDENDUM: On most SGI machines, the Zilog does possess
-	 *               a 16 or 17 byte fifo, so no worries. -dm
-	 */
-
-	if (info->x_char) {
-		/* Send next char */
-		udelay(2);
-		info->zs_channel->data = info->x_char;
-		junk = ioc_icontrol->istat0;
-
-		info->x_char = 0;
-		goto clear_and_return;
-	}
-
-	if((info->xmit_cnt <= 0) || info->tty->stopped) {
-		/* That's peculiar... */
-		udelay(2);
-		info->zs_channel->control = RES_Tx_P;
-		junk = ioc_icontrol->istat0;
-		goto clear_and_return;
-	}
-
-	/* Send char */
-	udelay(2);
-	info->zs_channel->data = info->xmit_buf[info->xmit_tail++];
-	junk = ioc_icontrol->istat0;
-
-	info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
-	info->xmit_cnt--;
-
-	if (info->xmit_cnt < WAKEUP_CHARS)
-		rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
-
-	if(info->xmit_cnt <= 0) {
-		udelay(2);
-		info->zs_channel->control = RES_Tx_P;
-		junk = ioc_icontrol->istat0;
-		goto clear_and_return;
-	}
-
-clear_and_return:
-	/* Clear interrupt */
-	udelay(2);
-	info->zs_channel->control = RES_H_IUS;
-	junk = ioc_icontrol->istat0;
-	return;
-}
-
-static _INLINE_ void status_handle(struct sgi_serial *info)
-{
-	volatile unsigned char junk;
-	unsigned char status;
-
-	/* Get status from Read Register 0 */
-	udelay(2);
-	status = info->zs_channel->control;
-	junk = ioc_icontrol->istat0;
-	/* Clear status condition... */
-	udelay(2);
-	info->zs_channel->control = RES_EXT_INT;
-	junk = ioc_icontrol->istat0;
-	/* Clear the interrupt */
-	udelay(2);
-	info->zs_channel->control = RES_H_IUS;
-	junk = ioc_icontrol->istat0;
-
-#if 0
-	if(status & DCD) {
-		if((info->tty->termios->c_cflag & CRTSCTS) &&
-		   ((info->curregs[3] & AUTO_ENAB)==0)) {
-			info->curregs[3] |= AUTO_ENAB;
-			info->pendregs[3] |= AUTO_ENAB;
-			write_zsreg(info->zs_channel, 3, info->curregs[3]);
-		}
-	} else {
-		if((info->curregs[3] & AUTO_ENAB)) {
-			info->curregs[3] &= ~AUTO_ENAB;
-			info->pendregs[3] &= ~AUTO_ENAB;
-			write_zsreg(info->zs_channel, 3, info->curregs[3]);
-		}
-	}
-#endif
-	/* Whee, if this is console input and this is a
-	 * 'break asserted' status change interrupt, call
-	 * the boot prom.
-	 */
-	if((status & BRK_ABRT) && info->break_abort)
-		batten_down_hatches();
-
-	/* XXX Whee, put in a buffer somewhere, the status information
-	 * XXX whee whee whee... Where does the information go...
-	 */
-	return;
-}
-
-/*
- * This is the serial driver's generic interrupt routine
- */
-void rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
-{
-	struct sgi_serial * info = (struct sgi_serial *) dev_id;
-	unsigned char zs_intreg;
-
-	zs_intreg = read_zsreg(info->zs_channel, 3);
-
-	/* NOTE: The read register 3, which holds the irq status,
-	 *       does so for both channels on each chip.  Although
-	 *       the status value itself must be read from the A
-	 *       channel and is only valid when read from channel A.
-	 *       Yes... broken hardware...
-	 */
-#define CHAN_A_IRQMASK (CHARxIP | CHATxIP | CHAEXT)
-#define CHAN_B_IRQMASK (CHBRxIP | CHBTxIP | CHBEXT)
-
-	/* *** Chip 1 *** */
-	/* Channel A -- /dev/ttya, could be the console */
-	if(zs_intreg & CHAN_A_IRQMASK) {
-		if (zs_intreg & CHARxIP)
-			receive_chars(info, regs);
-		if (zs_intreg & CHATxIP)
-			transmit_chars(info);
-		if (zs_intreg & CHAEXT)
-			status_handle(info);
-	}
-
-	info=info->zs_next;
-
-	/* Channel B -- /dev/ttyb, could be the console */
-	if(zs_intreg & CHAN_B_IRQMASK) {
-		if (zs_intreg & CHBRxIP)
-			receive_chars(info, regs);
-		if (zs_intreg & CHBTxIP)
-			transmit_chars(info);
-		if (zs_intreg & CHBEXT)
-			status_handle(info);
-	}
-}
-
-/*
- * -------------------------------------------------------------------
- * Here ends the serial interrupt routines.
- * -------------------------------------------------------------------
- */
-
-/*
- * This routine is used to handle the "bottom half" processing for the
- * serial driver, known also the "software interrupt" processing.
- * This processing is done at the kernel interrupt level, after the
- * rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON.  This
- * is where time-consuming activities which can not be done in the
- * interrupt driver proper are done; the interrupt driver schedules
- * them using rs_sched_event(), and they get done here.
- */
-static void do_serial_bh(void)
-{
-	run_task_queue(&tq_serial);
-}
-
-static void do_softint(void *private_)
-{
-	struct sgi_serial	*info = (struct sgi_serial *) private_;
-	struct tty_struct	*tty;
-	
-	tty = info->tty;
-	if (!tty)
-		return;
-
-	if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
-		if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
-		    tty->ldisc.write_wakeup)
-			(tty->ldisc.write_wakeup)(tty);
-		wake_up_interruptible(&tty->write_wait);
-	}
-}
-
-/*
- * This routine is called from the scheduler tqueue when the interrupt
- * routine has signalled that a hangup has occurred.  The path of
- * hangup processing is:
- *
- * 	serial interrupt routine -> (scheduler tqueue) ->
- * 	do_serial_hangup() -> tty->hangup() -> rs_hangup()
- * 
- */
-static void do_serial_hangup(void *private_)
-{
-	struct sgi_serial	*info = (struct sgi_serial *) private_;
-	struct tty_struct	*tty;
-	
-	tty = info->tty;
-	if (!tty)
-		return;
-
-	tty_hangup(tty);
-}
-
-
-/*
- * This subroutine is called when the RS_TIMER goes off.  It is used
- * by the serial driver to handle ports that do not have an interrupt
- * (irq=0).  This doesn't work at all for 16450's, as a sun has a Z8530.
- */
- 
-static void rs_timer(void)
-{
-	printk("rs_timer called\n");
-	prom_halt();
-	return;
-}
-
-static int startup(struct sgi_serial * info)
-{
-	volatile unsigned char junk;
-	unsigned long flags;
-
-	if (info->flags & ZILOG_INITIALIZED)
-		return 0;
-
-	if (!info->xmit_buf) {
-		info->xmit_buf = (unsigned char *) get_free_page(GFP_KERNEL);
-		if (!info->xmit_buf)
-			return -ENOMEM;
-	}
-
-	save_flags(flags); cli();
-
-#ifdef SERIAL_DEBUG_OPEN
-	printk("starting up ttys%d (irq %d)...", info->line, info->irq);
-#endif
-
-	/*
-	 * Clear the FIFO buffers and disable them
-	 * (they will be reenabled in change_speed())
-	 */
-	ZS_CLEARFIFO(info->zs_channel);
-	info->xmit_fifo_size = 1;
-
-	/*
-	 * Clear the interrupt registers.
-	 */
-	udelay(2);
-	info->zs_channel->control = ERR_RES;
-	junk = ioc_icontrol->istat0;
-	udelay(2);
-	info->zs_channel->control = RES_H_IUS;
-	junk = ioc_icontrol->istat0;
-
-	/*
-	 * Now, initialize the Zilog
-	 */
-	zs_rtsdtr(info, 1);
-
-	/*
-	 * Finally, enable sequencing and interrupts
-	 */
-	info->curregs[1] |= (info->curregs[1] & ~0x18) | (EXT_INT_ENAB|INT_ALL_Rx);
-	info->pendregs[1] = info->curregs[1];
-	info->curregs[3] |= (RxENABLE | Rx8);
-	info->pendregs[3] = info->curregs[3];
-	/* We enable Tx interrupts as needed. */
-	info->curregs[5] |= (TxENAB | Tx8);
-	info->pendregs[5] = info->curregs[5];
-	info->curregs[9] |= (NV | MIE);
-	info->pendregs[9] = info->curregs[9];
-	write_zsreg(info->zs_channel, 3, info->curregs[3]);
-	write_zsreg(info->zs_channel, 5, info->curregs[5]);
-	write_zsreg(info->zs_channel, 9, info->curregs[9]);
-	
-	/*
-	 * And clear the interrupt registers again for luck.
-	 */
-	udelay(2);
-	info->zs_channel->control = ERR_RES;
-	junk = ioc_icontrol->istat0;
-	udelay(2);
-	info->zs_channel->control = RES_H_IUS;
-	junk = ioc_icontrol->istat0;
-
-	if (info->tty)
-		clear_bit(TTY_IO_ERROR, &info->tty->flags);
-	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
-
-	/*
-	 * Set up serial timers...
-	 */
-#if 0  /* Works well and stops the machine. */
-	timer_table[RS_TIMER].expires = jiffies + 2;
-	timer_active |= 1 << RS_TIMER;
-#endif
-
-	/*
-	 * and set the speed of the serial port
-	 */
-	change_speed(info);
-
-	info->flags |= ZILOG_INITIALIZED;
-	restore_flags(flags);
-	return 0;
-}
-
-/*
- * This routine will shutdown a serial port; interrupts are disabled, and
- * DTR is dropped if the hangup on close termio flag is on.
- */
-static void shutdown(struct sgi_serial * info)
-{
-	unsigned long	flags;
-
-	if (!(info->flags & ZILOG_INITIALIZED))
-		return;
-
-#ifdef SERIAL_DEBUG_OPEN
-	printk("Shutting down serial port %d (irq %d)....", info->line,
-	       info->irq);
-#endif
-	
-	save_flags(flags); cli(); /* Disable interrupts */
-	
-	if (info->xmit_buf) {
-		free_page((unsigned long) info->xmit_buf);
-		info->xmit_buf = 0;
-	}
-
-	if (info->tty)
-		set_bit(TTY_IO_ERROR, &info->tty->flags);
-	
-	info->flags &= ~ZILOG_INITIALIZED;
-	restore_flags(flags);
-}
-
-/*
- * This routine is called to set the UART divisor registers to match
- * the specified baud rate for a serial port.
- */
-static void change_speed(struct sgi_serial *info)
-{
-	unsigned short port;
-	unsigned cflag;
-	int	i;
-	int	brg;
-
-	if (!info->tty || !info->tty->termios)
-		return;
-	cflag = info->tty->termios->c_cflag;
-	if (!(port = info->port))
-		return;
-	i = cflag & CBAUD;
-	if (i & CBAUDEX) {
-		/* XXX CBAUDEX is not obeyed.
-		 * It is impossible at a 32bits SPARC.
-		 * But we have to report this to user ... someday.
-		 */
-		i = B9600;
-	}
-	if (i == 0) {
-		/* XXX B0, hangup the line. */
-		do_serial_hangup(info);
-	} else if (baud_table[i]) {
-		info->zs_baud = baud_table[i];
-		info->clk_divisor = 16;
-
-		info->curregs[4] = X16CLK;
-		info->curregs[11] = TCBR | RCBR;
-		brg = BPS_TO_BRG(info->zs_baud, ZS_CLOCK/info->clk_divisor);
-		info->curregs[12] = (brg & 255);
-		info->curregs[13] = ((brg >> 8) & 255);
-		info->curregs[14] = BRENABL;
-	}
-
-	/* byte size and parity */
-	switch (cflag & CSIZE) {
-	case CS5:
-		info->curregs[3] &= ~(0xc0);
-		info->curregs[3] |= Rx5;
-		info->pendregs[3] = info->curregs[3];
-		info->curregs[5] &= ~(0xe0);
-		info->curregs[5] |= Tx5;
-		info->pendregs[5] = info->curregs[5];
-		break;
-	case CS6:
-		info->curregs[3] &= ~(0xc0);
-		info->curregs[3] |= Rx6;
-		info->pendregs[3] = info->curregs[3];
-		info->curregs[5] &= ~(0xe0);
-		info->curregs[5] |= Tx6;
-		info->pendregs[5] = info->curregs[5];
-		break;
-	case CS7:
-		info->curregs[3] &= ~(0xc0);
-		info->curregs[3] |= Rx7;
-		info->pendregs[3] = info->curregs[3];
-		info->curregs[5] &= ~(0xe0);
-		info->curregs[5] |= Tx7;
-		info->pendregs[5] = info->curregs[5];
-		break;
-	case CS8:
-	default: /* defaults to 8 bits */
-		info->curregs[3] &= ~(0xc0);
-		info->curregs[3] |= Rx8;
-		info->pendregs[3] = info->curregs[3];
-		info->curregs[5] &= ~(0xe0);
-		info->curregs[5] |= Tx8;
-		info->pendregs[5] = info->curregs[5];
-		break;
-	}
-	info->curregs[4] &= ~(0x0c);
-	if (cflag & CSTOPB) {
-		info->curregs[4] |= SB2;
-	} else {
-		info->curregs[4] |= SB1;
-	}
-	info->pendregs[4] = info->curregs[4];
-	if (cflag & PARENB) {
-		info->curregs[4] |= PAR_ENA;
-		info->pendregs[4] |= PAR_ENA;
-	} else {
-		info->curregs[4] &= ~PAR_ENA;
-		info->pendregs[4] &= ~PAR_ENA;
-	}
-	if (!(cflag & PARODD)) {
-		info->curregs[4] |= PAR_EVEN;
-		info->pendregs[4] |= PAR_EVEN;
-	} else {
-		info->curregs[4] &= ~PAR_EVEN;
-		info->pendregs[4] &= ~PAR_EVEN;
-	}
-
-	/* Load up the new values */
-	load_zsregs(info->zs_channel, info->curregs);
-
-	return;
-}
-
-/* This is for console output over ttya/ttyb */
-static void rs_put_char(char ch)
-{
-	struct sgi_zschannel *chan = zs_conschan;
-	volatile unsigned char junk;
-	int flags, loops = 0;
-
-	save_flags(flags); cli();
-	while(((junk = chan->control) & Tx_BUF_EMP)==0 && loops < 10000) {
-		loops++;
-		udelay(2);
-	}
-
-	udelay(2);
-	chan->data = ch;
-	junk = ioc_icontrol->istat0;
-	restore_flags(flags);
-}
-
-/* These are for receiving and sending characters under the kgdb
- * source level kernel debugger.
- */
-void putDebugChar(char kgdb_char)
-{
-	struct sgi_zschannel *chan = zs_kgdbchan;
-	volatile unsigned char junk;
-	unsigned long flags;
-
-	save_flags(flags); cli();
-	udelay(2);
-	while((chan->control & Tx_BUF_EMP)==0)
-		udelay(2);
-
-	udelay(2);
-	chan->data = kgdb_char;
-	junk = ioc_icontrol->istat0;
-	restore_flags(flags);
-}
-
-char getDebugChar(void)
-{
-	struct sgi_zschannel *chan = zs_kgdbchan;
-	unsigned char junk;
-
-	while((chan->control & Rx_CH_AV)==0)
-		udelay(2);
-
-	junk = ioc_icontrol->istat0;
-	udelay(2);
-	return chan->data;
-}
-
-/*
- * Fair output driver allows a process to speak.
- */
-static void rs_fair_output(void)
-{
-	int left;		/* Output no more than that */
-	unsigned long flags;
-	struct sgi_serial *info = zs_consinfo;
-	volatile unsigned char junk;
-	char c;
-
-	if (info == 0) return;
-	if (info->xmit_buf == 0) return;
-
-	save_flags(flags);  cli();
-	left = info->xmit_cnt;
-	while (left != 0) {
-		c = info->xmit_buf[info->xmit_tail];
-		info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1);
-		info->xmit_cnt--;
-		restore_flags(flags);
-
-		rs_put_char(c);
-
-		save_flags(flags);  cli();
-		left = MIN(info->xmit_cnt, left-1);
-	}
-
-	/* Last character is being transmitted now (hopefully). */
-	udelay(2);
-	zs_conschan->control = RES_Tx_P;
-	junk = ioc_icontrol->istat0;
-
-	restore_flags(flags);
-	return;
-}
-
-/*
- * zs_console_print is registered for printk.
- */
-static void zs_console_print(const char *p)
-{
-	char c;
-
-	while((c=*(p++)) != 0) {
-		if(c == '\n')
-			rs_put_char('\r');
-		rs_put_char(c);
-	}
-
-	/* Comment this if you want to have a strict interrupt-driven output */
-	rs_fair_output();
-}
-
-static void rs_flush_chars(struct tty_struct *tty)
-{
-	struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
-	unsigned long flags;
-
-	if (serial_paranoia_check(info, tty->device, "rs_flush_chars"))
-		return;
-
-	if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
-	    !info->xmit_buf)
-		return;
-
-	/* Enable transmitter */
-	save_flags(flags); cli();
-	info->curregs[1] |= TxINT_ENAB|EXT_INT_ENAB;
-	info->pendregs[1] |= TxINT_ENAB|EXT_INT_ENAB;
-	write_zsreg(info->zs_channel, 1, info->curregs[1]);
-	info->curregs[5] |= TxENAB;
-	info->pendregs[5] |= TxENAB;
-	write_zsreg(info->zs_channel, 5, info->curregs[5]);
-
-	/*
-	 * Send a first (bootstrapping) character. A best solution is
-	 * to call transmit_chars() here which handles output in a
-	 * generic way. Current transmit_chars() not only transmits,
-	 * but resets interrupts also what we do not desire here.
-	 * XXX Discuss with David.
-	 */
-	if (info->zs_channel->control & Tx_BUF_EMP) {
-		volatile unsigned char junk;
-
-		/* Send char */
-		udelay(2);
-		info->zs_channel->data = info->xmit_buf[info->xmit_tail++];
-		junk = ioc_icontrol->istat0;
-		info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
-		info->xmit_cnt--;
-	}
-	restore_flags(flags);
-}
-
-static int rs_write(struct tty_struct * tty, int from_user,
-		    const unsigned char *buf, int count)
-{
-	int	c, total = 0;
-	struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
-	unsigned long flags;
-
-	if (serial_paranoia_check(info, tty->device, "rs_write"))
-		return 0;
-
-	if (!tty || !info->xmit_buf)
-		return 0;
-
-	save_flags(flags);
-	while (1) {
-		cli();		
-		c = MIN(count, MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
-				   SERIAL_XMIT_SIZE - info->xmit_head));
-		if (c <= 0)
-			break;
-
-		if (from_user) {
-			down(&tmp_buf_sem);
-			copy_from_user(tmp_buf, buf, c);
-			c = MIN(c, MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
-				       SERIAL_XMIT_SIZE - info->xmit_head));
-			memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
-			up(&tmp_buf_sem);
-		} else
-			memcpy(info->xmit_buf + info->xmit_head, buf, c);
-		info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
-		info->xmit_cnt += c;
-		restore_flags(flags);
-		buf += c;
-		count -= c;
-		total += c;
-	}
-	if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped &&
-	    !(info->curregs[5] & TxENAB)) {
-		/* Enable transmitter */
-		info->curregs[1] |= TxINT_ENAB|EXT_INT_ENAB;
-		info->pendregs[1] |= TxINT_ENAB|EXT_INT_ENAB;
-		write_zsreg(info->zs_channel, 1, info->curregs[1]);
-		info->curregs[5] |= TxENAB;
-		info->pendregs[5] |= TxENAB;
-		write_zsreg(info->zs_channel, 5, info->curregs[5]);
-	}
-	restore_flags(flags);
-	return total;
-}
-
-static int rs_write_room(struct tty_struct *tty)
-{
-	struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
-	int	ret;
-				
-	if (serial_paranoia_check(info, tty->device, "rs_write_room"))
-		return 0;
-	ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
-	if (ret < 0)
-		ret = 0;
-	return ret;
-}
-
-static int rs_chars_in_buffer(struct tty_struct *tty)
-{
-	struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
-				
-	if (serial_paranoia_check(info, tty->device, "rs_chars_in_buffer"))
-		return 0;
-	return info->xmit_cnt;
-}
-
-static void rs_flush_buffer(struct tty_struct *tty)
-{
-	struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
-				
-	if (serial_paranoia_check(info, tty->device, "rs_flush_buffer"))
-		return;
-	cli();
-	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
-	sti();
-	wake_up_interruptible(&tty->write_wait);
-	if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
-	    tty->ldisc.write_wakeup)
-		(tty->ldisc.write_wakeup)(tty);
-}
-
-/*
- * ------------------------------------------------------------
- * rs_throttle()
- * 
- * This routine is called by the upper-layer tty layer to signal that
- * incoming characters should be throttled.
- * ------------------------------------------------------------
- */
-static void rs_throttle(struct tty_struct * tty)
-{
-	struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
-#ifdef SERIAL_DEBUG_THROTTLE
-	char	buf[64];
-	
-	printk("throttle %s: %d....\n", _tty_name(tty, buf),
-	       tty->ldisc.chars_in_buffer(tty));
-#endif
-
-	if (serial_paranoia_check(info, tty->device, "rs_throttle"))
-		return;
-	
-	if (I_IXOFF(tty))
-		info->x_char = STOP_CHAR(tty);
-
-	/* Turn off RTS line */
-	cli();
-	info->curregs[5] &= ~RTS;
-	info->pendregs[5] &= ~RTS;
-	write_zsreg(info->zs_channel, 5, info->curregs[5]);
-	sti();
-}
-
-static void rs_unthrottle(struct tty_struct * tty)
-{
-	struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
-#ifdef SERIAL_DEBUG_THROTTLE
-	char	buf[64];
-	
-	printk("unthrottle %s: %d....\n", _tty_name(tty, buf),
-	       tty->ldisc.chars_in_buffer(tty));
-#endif
-
-	if (serial_paranoia_check(info, tty->device, "rs_unthrottle"))
-		return;
-	
-	if (I_IXOFF(tty)) {
-		if (info->x_char)
-			info->x_char = 0;
-		else
-			info->x_char = START_CHAR(tty);
-	}
-
-	/* Assert RTS line */
-	cli();
-	info->curregs[5] |= RTS;
-	info->pendregs[5] |= RTS;
-	write_zsreg(info->zs_channel, 5, info->curregs[5]);
-	sti();
-}
-
-/*
- * ------------------------------------------------------------
- * rs_ioctl() and friends
- * ------------------------------------------------------------
- */
-
-static int get_serial_info(struct sgi_serial * info,
-			   struct serial_struct * retinfo)
-{
-	struct serial_struct tmp;
-  
-	if (!retinfo)
-		return -EFAULT;
-	memset(&tmp, 0, sizeof(tmp));
-	tmp.type = info->type;
-	tmp.line = info->line;
-	tmp.port = info->port;
-	tmp.irq = info->irq;
-	tmp.flags = info->flags;
-	tmp.baud_base = info->baud_base;
-	tmp.close_delay = info->close_delay;
-	tmp.closing_wait = info->closing_wait;
-	tmp.custom_divisor = info->custom_divisor;
-	return copy_to_user(retinfo,&tmp,sizeof(*retinfo));
-}
-
-static int set_serial_info(struct sgi_serial * info,
-			   struct serial_struct * new_info)
-{
-	struct serial_struct new_serial;
-	struct sgi_serial old_info;
-	int 			retval = 0;
-
-	if (!new_info)
-		return -EFAULT;
-	copy_from_user(&new_serial,new_info,sizeof(new_serial));
-	old_info = *info;
-
-	if (!suser()) {
-		if ((new_serial.baud_base != info->baud_base) ||
-		    (new_serial.type != info->type) ||
-		    (new_serial.close_delay != info->close_delay) ||
-		    ((new_serial.flags & ~ZILOG_USR_MASK) !=
-		     (info->flags & ~ZILOG_USR_MASK)))
-			return -EPERM;
-		info->flags = ((info->flags & ~ZILOG_USR_MASK) |
-			       (new_serial.flags & ZILOG_USR_MASK));
-		info->custom_divisor = new_serial.custom_divisor;
-		goto check_and_exit;
-	}
-
-	if (info->count > 1)
-		return -EBUSY;
-
-	/*
-	 * OK, past this point, all the error checking has been done.
-	 * At this point, we start making changes.....
-	 */
-
-	info->baud_base = new_serial.baud_base;
-	info->flags = ((info->flags & ~ZILOG_FLAGS) |
-			(new_serial.flags & ZILOG_FLAGS));
-	info->type = new_serial.type;
-	info->close_delay = new_serial.close_delay;
-	info->closing_wait = new_serial.closing_wait;
-
-check_and_exit:
-	retval = startup(info);
-	return retval;
-}
-
-/*
- * get_lsr_info - get line status register info
- *
- * Purpose: Let user call ioctl() to get info when the UART physically
- * 	    is emptied.  On bus types like RS485, the transmitter must
- * 	    release the bus after transmitting. This must be done when
- * 	    the transmit shift register is empty, not be done when the
- * 	    transmit holding register is empty.  This functionality
- * 	    allows an RS485 driver to be written in user space. 
- */
-static int get_lsr_info(struct sgi_serial * info, unsigned int *value)
-{
-	volatile unsigned char junk;
-	unsigned char status;
-
-	cli();
-	udelay(2);
-	status = info->zs_channel->control;
-	junk = ioc_icontrol->istat0;
-	sti();
-	return put_user(status,value);
-}
-
-/*
- * This routine sends a break character out the serial port.
- */
-static void send_break(	struct sgi_serial * info, int duration)
-{
-	if (!info->port)
-		return;
-	current->state = TASK_INTERRUPTIBLE;
-	current->timeout = jiffies + duration;
-	cli();
-	write_zsreg(info->zs_channel, 5, (info->curregs[5] | SND_BRK));
-	schedule();
-	write_zsreg(info->zs_channel, 5, info->curregs[5]);
-	sti();
-}
-
-static int rs_ioctl(struct tty_struct *tty, struct file * file,
-		    unsigned int cmd, unsigned long arg)
-{
-	int error;
-	struct sgi_serial * info = (struct sgi_serial *)tty->driver_data;
-	int retval;
-
-	if (serial_paranoia_check(info, tty->device, "rs_ioctl"))
-		return -ENODEV;
-
-	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
-	    (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD)  &&
-	    (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
-		if (tty->flags & (1 << TTY_IO_ERROR))
-		    return -EIO;
-	}
-	
-	switch (cmd) {
-		case TCSBRK:	/* SVID version: non-zero arg --> no break */
-			retval = tty_check_change(tty);
-			if (retval)
-				return retval;
-			tty_wait_until_sent(tty, 0);
-			if (!arg)
-				send_break(info, HZ/4);	/* 1/4 second */
-			return 0;
-		case TCSBRKP:	/* support for POSIX tcsendbreak() */
-			retval = tty_check_change(tty);
-			if (retval)
-				return retval;
-			tty_wait_until_sent(tty, 0);
-			send_break(info, arg ? arg*(HZ/10) : HZ/4);
-			return 0;
-		case TIOCGSOFTCAR:
-			error = verify_area(VERIFY_WRITE, (void *) arg,sizeof(long));
-			if (error)
-				return error;
-			put_user(C_CLOCAL(tty) ? 1 : 0,
-			         (unsigned long *) arg);
-			return 0;
-		case TIOCSSOFTCAR:
-			error = get_user(arg, (unsigned long *)arg);
-			if (error)
-				return error;
-			tty->termios->c_cflag =
-				((tty->termios->c_cflag & ~CLOCAL) |
-				 (arg ? CLOCAL : 0));
-			return 0;
-		case TIOCGSERIAL:
-			error = verify_area(VERIFY_WRITE, (void *) arg,
-						sizeof(struct serial_struct));
-			if (error)
-				return error;
-			return get_serial_info(info,
-					       (struct serial_struct *) arg);
-		case TIOCSSERIAL:
-			return set_serial_info(info,
-					       (struct serial_struct *) arg);
-		case TIOCSERGETLSR: /* Get line status register */
-			error = verify_area(VERIFY_WRITE, (void *) arg,
-				sizeof(unsigned int));
-			if (error)
-				return error;
-			else
-			    return get_lsr_info(info, (unsigned int *) arg);
-
-		case TIOCSERGSTRUCT:
-			error = verify_area(VERIFY_WRITE, (void *) arg,
-						sizeof(struct sgi_serial));
-			if (error)
-				return error;
-			copy_to_user((struct sun_serial *) arg,
-				    info, sizeof(struct sgi_serial));
-			return 0;
-			
-		default:
-			return -ENOIOCTLCMD;
-		}
-	return 0;
-}
-
-static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
-{
-	struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
-
-	if (tty->termios->c_cflag == old_termios->c_cflag)
-		return;
-
-	change_speed(info);
-
-	if ((old_termios->c_cflag & CRTSCTS) &&
-	    !(tty->termios->c_cflag & CRTSCTS)) {
-		tty->hw_stopped = 0;
-		rs_start(tty);
-	}
-}
-
-/*
- * ------------------------------------------------------------
- * rs_close()
- * 
- * This routine is called when the serial port gets closed.  First, we
- * wait for the last remaining data to be sent.  Then, we unlink its
- * ZILOG structure from the interrupt chain if necessary, and we free
- * that IRQ if nothing is left in the chain.
- * ------------------------------------------------------------
- */
-static void rs_close(struct tty_struct *tty, struct file * filp)
-{
-	struct sgi_serial * info = (struct sgi_serial *)tty->driver_data;
-	unsigned long flags;
-
-	if (!info || serial_paranoia_check(info, tty->device, "rs_close"))
-		return;
-	
-	save_flags(flags); cli();
-	
-	if (tty_hung_up_p(filp)) {
-		restore_flags(flags);
-		return;
-	}
-	
-#ifdef SERIAL_DEBUG_OPEN
-	printk("rs_close ttys%d, count = %d\n", info->line, info->count);
-#endif
-	if ((tty->count == 1) && (info->count != 1)) {
-		/*
-		 * Uh, oh.  tty->count is 1, which means that the tty
-		 * structure will be freed.  Info->count should always
-		 * be one in these conditions.  If it's greater than
-		 * one, we've got real problems, since it means the
-		 * serial port won't be shutdown.
-		 */
-		printk("rs_close: bad serial port count; tty->count is 1, "
-		       "info->count is %d\n", info->count);
-		info->count = 1;
-	}
-	if (--info->count < 0) {
-		printk("rs_close: bad serial port count for ttys%d: %d\n",
-		       info->line, info->count);
-		info->count = 0;
-	}
-	if (info->count) {
-		restore_flags(flags);
-		return;
-	}
-	info->flags |= ZILOG_CLOSING;
-	/*
-	 * Save the termios structure, since this port may have
-	 * separate termios for callout and dialin.
-	 */
-	if (info->flags & ZILOG_NORMAL_ACTIVE)
-		info->normal_termios = *tty->termios;
-	if (info->flags & ZILOG_CALLOUT_ACTIVE)
-		info->callout_termios = *tty->termios;
-	/*
-	 * Now we wait for the transmit buffer to clear; and we notify 
-	 * the line discipline to only process XON/XOFF characters.
-	 */
-	tty->closing = 1;
-	if (info->closing_wait != ZILOG_CLOSING_WAIT_NONE)
-		tty_wait_until_sent(tty, info->closing_wait);
-	/*
-	 * At this point we stop accepting input.  To do this, we
-	 * disable the receive line status interrupts, and tell the
-	 * interrupt driver to stop checking the data ready bit in the
-	 * line status register.
-	 */
-	/** if (!info->iscons) ... **/
-	info->curregs[3] &= ~RxENABLE;
-	info->pendregs[3] = info->curregs[3];
-	write_zsreg(info->zs_channel, 3, info->curregs[3]);
-	info->curregs[1] &= ~(0x18);
-	info->pendregs[1] = info->curregs[1];
-	write_zsreg(info->zs_channel, 1, info->curregs[1]);
-	ZS_CLEARFIFO(info->zs_channel);
-
-	shutdown(info);
-	if (tty->driver.flush_buffer)
-		tty->driver.flush_buffer(tty);
-	if (tty->ldisc.flush_buffer)
-		tty->ldisc.flush_buffer(tty);
-	tty->closing = 0;
-	info->event = 0;
-	info->tty = 0;
-	if (tty->ldisc.num != ldiscs[N_TTY].num) {
-		if (tty->ldisc.close)
-			(tty->ldisc.close)(tty);
-		tty->ldisc = ldiscs[N_TTY];
-		tty->termios->c_line = N_TTY;
-		if (tty->ldisc.open)
-			(tty->ldisc.open)(tty);
-	}
-	if (info->blocked_open) {
-		if (info->close_delay) {
-			current->state = TASK_INTERRUPTIBLE;
-			current->timeout = jiffies + info->close_delay;
-			schedule();
-		}
-		wake_up_interruptible(&info->open_wait);
-	}
-	info->flags &= ~(ZILOG_NORMAL_ACTIVE|ZILOG_CALLOUT_ACTIVE|
-			 ZILOG_CLOSING);
-	wake_up_interruptible(&info->close_wait);
-	restore_flags(flags);
-}
-
-/*
- * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
- */
-void rs_hangup(struct tty_struct *tty)
-{
-	struct sgi_serial * info = (struct sgi_serial *)tty->driver_data;
-	
-	if (serial_paranoia_check(info, tty->device, "rs_hangup"))
-		return;
-	
-	rs_flush_buffer(tty);
-	shutdown(info);
-	info->event = 0;
-	info->count = 0;
-	info->flags &= ~(ZILOG_NORMAL_ACTIVE|ZILOG_CALLOUT_ACTIVE);
-	info->tty = 0;
-	wake_up_interruptible(&info->open_wait);
-}
-
-/*
- * ------------------------------------------------------------
- * rs_open() and friends
- * ------------------------------------------------------------
- */
-static int block_til_ready(struct tty_struct *tty, struct file * filp,
-			   struct sgi_serial *info)
-{
-	struct wait_queue wait = { current, NULL };
-	int		retval;
-	int		do_clocal = 0;
-
-	/*
-	 * If the device is in the middle of being closed, then block
-	 * until it's done, and then try again.
-	 */
-	if (info->flags & ZILOG_CLOSING) {
-		interruptible_sleep_on(&info->close_wait);
-#ifdef SERIAL_DO_RESTART
-		if (info->flags & ZILOG_HUP_NOTIFY)
-			return -EAGAIN;
-		else
-			return -ERESTARTSYS;
-#else
-		return -EAGAIN;
-#endif
-	}
-
-	/*
-	 * If this is a callout device, then just make sure the normal
-	 * device isn't being used.
-	 */
-	if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) {
-		if (info->flags & ZILOG_NORMAL_ACTIVE)
-			return -EBUSY;
-		if ((info->flags & ZILOG_CALLOUT_ACTIVE) &&
-		    (info->flags & ZILOG_SESSION_LOCKOUT) &&
-		    (info->session != current->session))
-		    return -EBUSY;
-		if ((info->flags & ZILOG_CALLOUT_ACTIVE) &&
-		    (info->flags & ZILOG_PGRP_LOCKOUT) &&
-		    (info->pgrp != current->pgrp))
-		    return -EBUSY;
-		info->flags |= ZILOG_CALLOUT_ACTIVE;
-		return 0;
-	}
-	
-	/*
-	 * If non-blocking mode is set, or the port is not enabled,
-	 * then make the check up front and then exit.
-	 */
-	if ((filp->f_flags & O_NONBLOCK) ||
-	    (tty->flags & (1 << TTY_IO_ERROR))) {
-		if (info->flags & ZILOG_CALLOUT_ACTIVE)
-			return -EBUSY;
-		info->flags |= ZILOG_NORMAL_ACTIVE;
-		return 0;
-	}
-
-	if (info->flags & ZILOG_CALLOUT_ACTIVE) {
-		if (info->normal_termios.c_cflag & CLOCAL)
-			do_clocal = 1;
-	} else {
-		if (tty->termios->c_cflag & CLOCAL)
-			do_clocal = 1;
-	}
-	
-	/*
-	 * Block waiting for the carrier detect and the line to become
-	 * free (i.e., not in use by the callout).  While we are in
-	 * this loop, info->count is dropped by one, so that
-	 * rs_close() knows when to free things.  We restore it upon
-	 * exit, either normal or abnormal.
-	 */
-	retval = 0;
-	add_wait_queue(&info->open_wait, &wait);
-#ifdef SERIAL_DEBUG_OPEN
-	printk("block_til_ready before block: ttys%d, count = %d\n",
-	       info->line, info->count);
-#endif
-	info->count--;
-	info->blocked_open++;
-	while (1) {
-		cli();
-		if (!(info->flags & ZILOG_CALLOUT_ACTIVE))
-			zs_rtsdtr(info, 1);
-		sti();
-		current->state = TASK_INTERRUPTIBLE;
-		if (tty_hung_up_p(filp) ||
-		    !(info->flags & ZILOG_INITIALIZED)) {
-#ifdef SERIAL_DO_RESTART
-			if (info->flags & ZILOG_HUP_NOTIFY)
-				retval = -EAGAIN;
-			else
-				retval = -ERESTARTSYS;	
-#else
-			retval = -EAGAIN;
-#endif
-			break;
-		}
-		if (!(info->flags & ZILOG_CALLOUT_ACTIVE) &&
-		    !(info->flags & ZILOG_CLOSING) && do_clocal)
-			break;
 		if (signal_pending(current)) {
 			retval = -ERESTARTSYS;
 			break;