/*
* decserial.c: Serial port driver for IOASIC DECstations.
*
* Derived from drivers/sbus/char/sunserial.c by Paul Mackerras.
* Derived from drivers/macintosh/macserial.c by Harald Koerfgen.
*
* DECstation changes
* Copyright (C) 1998-2000 Harald Koerfgen
* Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005 Maciej W. Rozycki
*
* For the rest of the code the original Copyright applies:
* Copyright (C) 1996 Paul Mackerras (Paul.Mackerras@cs.anu.edu.au)
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
*
*
* Note: for IOASIC systems the wiring is as follows:
*
* mouse/keyboard:
* DIN-7 MJ-4 signal SCC
* 2 1 TxD <- A.TxD
* 3 4 RxD -> A.RxD
*
* EIA-232/EIA-423:
* DB-25 MMJ-6 signal SCC
* 2 2 TxD <- B.TxD
* 3 5 RxD -> B.RxD
* 4 RTS <- ~A.RTS
* 5 CTS -> ~B.CTS
* 6 6 DSR -> ~A.SYNC
* 8 CD -> ~B.DCD
* 12 DSRS(DCE) -> ~A.CTS (*)
* 15 TxC -> B.TxC
* 17 RxC -> B.RxC
* 20 1 DTR <- ~A.DTR
* 22 RI -> ~A.DCD
* 23 DSRS(DTE) <- ~B.RTS
*
* (*) EIA-232 defines the signal at this pin to be SCD, while DSRS(DCE)
* is shared with DSRS(DTE) at pin 23.
*/
#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 <linux/init.h>
#include <linux/ioport.h>
#include <linux/spinlock.h>
#ifdef CONFIG_SERIAL_DEC_CONSOLE
#include <linux/console.h>
#endif
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/bootinfo.h>
#include <asm/dec/interrupts.h>
#include <asm/dec/ioasic_addrs.h>
#include <asm/dec/machtype.h>
#include <asm/dec/serial.h>
#include <asm/dec/system.h>
#include <asm/dec/tc.h>
#ifdef CONFIG_KGDB
#include <asm/kgdb.h>
#endif
#ifdef CONFIG_MAGIC_SYSRQ
#include <linux/sysrq.h>
#endif
#include "zs.h"
/*
* It would be nice to dynamically allocate everything that
* depends on NUM_SERIAL, so we could support any number of
* Z8530s, but for now...
*/
#define NUM_SERIAL 2 /* Max number of ZS chips supported */
#define NUM_CHANNELS (NUM_SERIAL * 2) /* 2 channels per chip */
#define CHANNEL_A_NR (zs_parms->channel_a_offset > zs_parms->channel_b_offset)
/* Number of channel A in the chip */
#define ZS_CHAN_IO_SIZE 8
#define ZS_CLOCK 7372800 /* Z8530 RTxC input clock rate */
#define RECOVERY_DELAY udelay(2)
struct zs_parms {
unsigned long scc0;
unsigned long scc1;
int channel_a_offset;
int channel_b_offset;
int irq0;
int irq1;
int clock;
};
static struct zs_parms *zs_parms;
#ifdef CONFIG_MACH_DECSTATION
static struct zs_parms ds_parms = {
scc0 : IOASIC_SCC0,
scc1 : IOASIC_SCC1,
channel_a_offset : 1,
channel_b_offset : 9,
irq0 : -1,
irq1 : -1,
clock : ZS_CLOCK
};
#endif
#ifdef CONFIG_MACH_DECSTATION
#define DS_BUS_PRESENT (IOASIC)
#else
#define DS_BUS_PRESENT 0
#endif
#define BUS_PRESENT (DS_BUS_PRESENT)
DEFINE_SPINLOCK(zs_lock);
struct dec_zschannel zs_channels[NUM_CHANNELS];
struct dec_serial zs_soft[NUM_CHANNELS];
int zs_channels_found;
struct dec_serial *zs_chain; /* list of all channels */
struct tty_struct zs_ttys[NUM_CHANNELS];
#ifdef CONFIG_SERIAL_DEC_CONSOLE
static struct console sercons;
#endif
#if defined(CONFIG_SERIAL_DEC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) && \
!defined(MODULE)
static unsigned long break_pressed; /* break, really ... */
#endif
static unsigned char zs_init_regs[16] __initdata = {
0, /* write 0 */
0, /* write 1 */
0, /* write 2 */
0, /* write 3 */
(X16CLK), /* write 4 */
0, /* write 5 */
0, 0, 0, /* write 6, 7, 8 */
(MIE | DLC | NV), /* write 9 */
(NRZ), /* write 10 */
(TCBR | RCBR), /* write 11 */
0, 0, /* BRG time constant, write 12 + 13 */
(BRSRC | BRENABL), /* write 14 */
0 /* write 15 */
};
static struct tty_driver *serial_driver;
/* serial subtype definitions */
#define SERIAL_TYPE_NORMAL 1
/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS 256
/*
* Debugging.
*/
#undef SERIAL_DEBUG_OPEN
#undef SERIAL_DEBUG_FLOW
#undef SERIAL_DEBUG_THROTTLE
#undef SERIAL_PARANOIA_CHECK
#undef ZS_DEBUG_REGS
#ifdef SERIAL_DEBUG_THROTTLE
#define _tty_name(tty,buf) tty_name(tty,buf)
#endif
#define RS_STROBE_TIME 10
#define RS_ISR_PASS_LIMIT 256
static void probe_sccs(void);
static void change_speed(struct dec_serial *info);
static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
static inline int serial_paranoia_check(struct dec_serial *info,
char *name, const char *routine)
{
#ifdef SERIAL_PARANOIA_CHECK
static const char *badmagic =
"Warning: bad magic number for serial struct %s in %s\n";
static const char *badinfo =
"Warning: null mac_serial for %s in %s\n";
if (!info) {
printk(badinfo, name, routine);
return 1;
}
if (info->magic != SERIAL_MAGIC) {
printk(badmagic, name, 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 Z8530 registers.
*/
static inline unsigned char read_zsreg(struct dec_zschannel *channel,
unsigned char reg)
{
unsigned char retval;
if (reg != 0) {
*channel->control = reg & 0xf;
fast_iob(); RECOVERY_DELAY;
}
retval = *channel->control;
RECOVERY_DELAY;
return retval;
}
static inline void write_zsreg(struct dec_zschannel *channel,
unsigned char reg, unsigned char value)
{
if (reg != 0) {
*channel->control = reg & 0xf;
fast_iob(); RECOVERY_DELAY;
}
*channel->control = value;
fast_iob(); RECOVERY_DELAY;
return;
}
static inline unsigned char read_zsdata(struct dec_zschannel *channel)
{
unsigned char retval;
retval = *channel->data;
RECOVERY_DELAY;
return retval;
}
static inline void write_zsdata(struct dec_zschannel *channel,
unsigned char value)
{
*channel->data = value;
fast_iob(); RECOVERY_DELAY;
return;
}
static inline void load_zsregs(struct dec_zschannel *channel,
unsigned char *regs)
{
/* ZS_CLEARERR(channel);
ZS_CLEARFIFO(channel); */
/* Load 'em up */
write_zsreg(channel, R3, regs[R3] & ~RxENABLE);
write_zsreg(channel, R5, regs[R5] & ~TxENAB);
write_zsreg(channel, R4, regs[R4]);
write_zsreg(channel, R9, regs[R9]);
write_zsreg(channel, R1, regs[R1]);
write_zsreg(channel, R2, regs[R2]);
write_zsreg(channel, R10, regs[R10]);
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 dec_serial *info, int which, int set)
{
unsigned long flags;
spin_lock_irqsave(&zs_lock, flags);
if (info->zs_channel != info->zs_chan_a) {
if (set) {
info->zs_chan_a->curregs[5] |= (which & (RTS | DTR));
} else {
info->zs_chan_a->curregs[5] &= ~(which & (RTS | DTR));
}
write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
}
spin_unlock_irqrestore(&zs_lock, flags);
}
/* Utility routines for the Zilog */
static inline int get_zsbaud(struct dec_serial *ss)
{
struct dec_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) << 8);
brg |= read_zsreg(channel, 12);
return BRG_TO_BPS(brg, (zs_parms->clock/(ss->clk_divisor)));
}
/* On receive, this clears errors and the receiver interrupts */
static inline void rs_recv_clear(struct dec_zschannel *zsc)
{
write_zsreg(zsc, 0, ERR_RES);
write_zsreg(zsc, 0, RES_H_IUS); /* XXX this is unnecessary */
}
/*
* ----------------------------------------------------------------------
*
* 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.
*
* - 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 void rs_sched_event(struct dec_serial *info, int event)
{
info->event |= 1 << event;
tasklet_schedule(&info->tlet);
}
static void receive_chars(struct dec_serial *info)
{
struct tty_struct *tty = info->tty;
unsigned char ch, stat, flag;
while ((read_zsreg(info->zs_channel, R0) & Rx_CH_AV) != 0) {
stat = read_zsreg(info->zs_channel, R1);
ch = read_zsdata(info->zs_channel);
if (!tty && (!info->hook || !info->hook->rx_char))
continue;
flag = TTY_NORMAL;
if (info->tty_break) {
info->tty_break = 0;
flag = TTY_BREAK;
if (info->flags & ZILOG_SAK)
do_SAK(tty);
/* Ignore the null char got when BREAK is removed. */
if (ch == 0)
continue;
} else {
if (stat & Rx_OVR) {
flag = TTY_OVERRUN;
} else if (stat & FRM_ERR) {
flag = TTY_FRAME;
} else if (stat & PAR_ERR) {
flag = TTY_PARITY;
}
if (flag != TTY_NORMAL)
/* reset the error indication */
write_zsreg(info->zs_channel, R0, ERR_RES);
}
#if defined(CONFIG_SERIAL_DEC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) && \
!defined(MODULE)
if (break_pressed && info->line == sercons.index) {
/* Ignore the null char got when BREAK is removed. */
if (ch == 0)
continue;
if (time_before(jiffies, break_pressed + HZ * 5)) {
handle_sysrq(ch, NULL);
break_pressed = 0;
continue;
}
break_pressed = 0;
}
#endif
if (info->hook && info->hook->rx_char) {
(*info->hook->rx_char)(ch, flag);
return;
}
tty_insert_flip_char(tty, ch, flag);
}
if (tty)
tty_flip_buffer_push(tty);
}
static void transmit_chars(struct dec_serial *info)
{
if ((read_zsreg(info->zs_channel, R0) & Tx_BUF_EMP) == 0)
return;
info->tx_active = 0;
if (info->x_char) {
/* Send next char */
write_zsdata(info->zs_channel, info->x_char);
info->x_char = 0;
info->tx_active = 1;
return;
}
if ((info->xmit_cnt <= 0) || (info->tty && info->tty->stopped)
|| info->tx_stopped) {
write_zsreg(info->zs_channel, R0, RES_Tx_P);
return;
}
/* Send char */
write_zsdata(info->zs_channel, info->xmit_buf[info->xmit_tail++]);
info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt--;
info->tx_active = 1;
if (info->xmit_cnt < WAKEUP_CHARS)
rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
}
static void status_handle(struct dec_serial *info)
{
unsigned char stat;
/* Get status from Read Register 0 */
stat = read_zsreg(info->zs_channel, R0);
if ((stat & BRK_ABRT) && !(info->read_reg_zero & BRK_ABRT)) {
#if defined(CONFIG_SERIAL_DEC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) && \
!defined(MODULE)
if (info->line == sercons.index) {
if (!break_pressed)
break_pressed = jiffies;
} else
#endif
info->tty_break = 1;
}
if (info->zs_channel != info->zs_chan_a) {
/* Check for DCD transitions */
if (info->tty && !C_CLOCAL(info->tty) &&
((stat ^ info->read_reg_zero) & DCD) != 0 ) {
if (stat & DCD) {
wake_up_interruptible(&info->open_wait);
} else {
tty_hangup(info->tty);
}
}
/* Check for CTS transitions */
if (info->tty && C_CRTSCTS(info->tty)) {
if ((stat & CTS) != 0) {
if (info->tx_stopped) {
info->tx_stopped = 0;
if (!info->tx_active)
transmit_chars(info);
}
} else {
info->tx_stopped = 1;
}
}
}
/* Clear status condition... */
write_zsreg(info->zs_channel, R0, RES_EXT_INT);
info->read_reg_zero = stat;
}
/*
* This is the serial driver's generic interrupt routine
*/
static irqreturn_t rs_interrupt(int irq, void *dev_id)
{
struct dec_serial *info = (struct dec_serial *) dev_id;
irqreturn_t status = IRQ_NONE;
unsigned char zs_intreg;
int shift;
/* 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_IRQMASK (CHBRxIP | CHBTxIP | CHBEXT)
if (info->zs_chan_a == info->zs_channel)
shift = 3; /* Channel A */
else
shift = 0; /* Channel B */
for (;;) {
zs_intreg = read_zsreg(info->zs_chan_a, R3) >> shift;
if ((zs_intreg & CHAN_IRQMASK) == 0)
break;
status = IRQ_HANDLED;
if (zs_intreg & CHBRxIP) {
receive_chars(info);
}
if (zs_intreg & CHBTxIP) {
transmit_chars(info);
}
if (zs_intreg & CHBEXT) {
status_handle(info);
}
}
/* Why do we need this ? */
write_zsreg(info->zs_channel, 0, RES_H_IUS);
return status;
}
#ifdef ZS_DEBUG_REGS
void zs_dump (void) {
int i, j;
for (i = 0; i < zs_channels_found; i++) {
struct dec_zschannel *ch = &zs_channels[i];
if ((long)ch->control == UNI_IO_BASE+UNI_SCC1A_CTRL) {
for (j = 0; j < 15; j++) {
printk("W%d = 0x%x\t",
j, (int)ch->curregs[j]);
}
for (j = 0; j < 15; j++) {
printk("R%d = 0x%x\t",
j, (int)read_zsreg(ch,j));
}
printk("\n\n");
}
}
}
#endif
/*
* -------------------------------------------------------------------
* Here ends the serial interrupt routines.
* -------------------------------------------------------------------
*/
/*
* ------------------------------------------------------------
* rs_stop() and rs_start()
*
* This routines are called before setting or resetting tty->stopped.
* ------------------------------------------------------------
*/
static void rs_stop(struct tty_struct *tty)
{
struct dec_serial *info = (struct dec_serial *)tty->driver_data;
unsigned long flags;
if (serial_paranoia_check(info, tty->name, "rs_stop"))
return;
#if 1
spin_lock_irqsave(&zs_lock, flags);
if (info->zs_channel->curregs[5] & TxENAB) {
info->zs_channel->curregs[5] &= ~TxENAB;
write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
}
spin_unlock_irqrestore(&zs_lock, flags);
#endif
}
static void rs_start(struct tty_struct *tty)
{
struct dec_serial *info = (struct dec_serial *)tty->driver_data;
unsigned long flags;
if (serial_paranoia_check(info, tty->name, "rs_start"))
return;
spin_lock_irqsave(&zs_lock, flags);
#if 1
if (info->xmit_cnt && info->xmit_buf && !(info->zs_channel->curregs[5] & TxENAB)) {
info->zs_channel->curregs[5] |= TxENAB;
write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
}
#else
if (info->xmit_cnt && info->xmit_buf && !info->tx_active) {
transmit_chars(info);
}
#endif
spin_unlock_irqrestore(&zs_lock, flags);
}
/*
* 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_softint(unsigned long private_)
{
struct dec_serial *info = (struct dec_serial *) private_;
struct tty_struct *tty;
tty = info->tty;
if (!tty)
return;
if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
tty_wakeup(tty);
wake_up_interruptible(&tty->write_wait);
}
}
static int zs_startup(struct dec_serial * info)
{
unsigned long flags;
if (info->flags & ZILOG_INITIALIZED)
return 0;
if (!info->xmit_buf) {
info->xmit_buf = (unsigned char *) get_zeroed_page(GFP_KERNEL);
if (!info->xmit_buf)
return -ENOMEM;
}
spin_lock_irqsave(&zs_lock, flags);
#ifdef SERIAL_DEBUG_OPEN
printk("starting up ttyS%d (irq %d)...", info->line, info->irq);
#endif
/*
* Clear the receive FIFO.
*/
ZS_CLEARFIFO(info->zs_channel);
info->xmit_fifo_size = 1;
/*
* Clear the interrupt registers.
*/
write_zsreg(info->zs_channel, R0, ERR_RES);
write_zsreg(info->zs_channel, R0, RES_H_IUS);
/*
* Set the speed of the serial port
*/
change_speed(info);
/*
* Turn on RTS and DTR.
*/
zs_rtsdtr(info, RTS | DTR, 1);
/*
* Finally, enable sequencing and interrupts
*/
info->zs_channel->curregs[R1] &= ~RxINT_MASK;
info->zs_channel->curregs[R1] |= (RxINT_ALL | TxINT_ENAB |
EXT_INT_ENAB);
info->zs_channel->curregs[R3] |= RxENABLE;
info->zs_channel->curregs[R5] |= TxENAB;
info->zs_channel->curregs[R15] |= (DCDIE | CTSIE | TxUIE | BRKIE);
write_zsreg(info->zs_channel, R1, info->zs_channel->curregs[R1]);
write_zsreg(info->zs_channel, R3, info->zs_channel->curregs[R3]);
write_zsreg(info->zs_channel, R5, info->zs_channel->curregs[R5]);
write_zsreg(info->zs_channel, R15, info->zs_channel->curregs[R15]);
/*
* And clear the interrupt registers again for luck.
*/
write_zsreg(info->zs_channel, R0, ERR_RES);
write_zsreg(info->zs_channel, R0, RES_H_IUS);
/* Save the current value of RR0 */
info->read_reg_zero = read_zsreg(info->zs_channel, R0);
if (info->tty)
clear_bit(TTY_IO_ERROR, &info->tty->flags);
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
info->flags |= ZILOG_INITIALIZED;
spin_unlock_irqrestore(&zs_lock, 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 dec_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
spin_lock_irqsave(&zs_lock, flags);
if (info->xmit_buf) {
free_page((unsigned long) info->xmit_buf);
info->xmit_buf = 0;
}
info->zs_channel->curregs[1] = 0;
write_zsreg(info->zs_channel, 1, info->zs_channel->curregs[1]); /* no interrupts */
info->zs_channel->curregs[3] &= ~RxENABLE;
write_zsreg(info->zs_channel, 3, info->zs_channel->curregs[3]);
info->zs_channel->curregs[5] &= ~TxENAB;
write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
if (!info->tty || C_HUPCL(info->tty)) {
zs_rtsdtr(info, RTS | DTR, 0);
}
if (info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);
info->flags &= ~ZILOG_INITIALIZED;
spin_unlock_irqrestore(&zs_lock, 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 dec_serial *info)
{
unsigned cflag;
int i;
int brg, bits;
unsigned long flags;
if (!info->hook) {
if (!info->tty || !info->tty->termios)
return;
cflag = info->tty->termios->c_cflag;
if (!info->port)
return;
} else {
cflag = info->hook->cflags;
}
i = cflag & CBAUD;
if (i & CBAUDEX) {
i &= ~CBAUDEX;
if (i < 1 || i > 2) {
if (!info->hook)
info->tty->termios->c_cflag &= ~CBAUDEX;
else
info->hook->cflags &= ~CBAUDEX;
} else
i += 15;
}
spin_lock_irqsave(&zs_lock, flags);
info->zs_baud = baud_table[i];
if (info->zs_baud) {
brg = BPS_TO_BRG(info->zs_baud, zs_parms->clock/info->clk_divisor);
info->zs_channel->curregs[12] = (brg & 255);
info->zs_channel->curregs[13] = ((brg >> 8) & 255);
zs_rtsdtr(info, DTR, 1);
} else {
zs_rtsdtr(info, RTS | DTR, 0);
return;
}
/* byte size and parity */
info->zs_channel->curregs[3] &= ~RxNBITS_MASK;
info->zs_channel->curregs[5] &= ~TxNBITS_MASK;
switch (cflag & CSIZE) {
case CS5:
bits = 7;
info->zs_channel->curregs[3] |= Rx5;
info->zs_channel->curregs[5] |= Tx5;
break;
case CS6:
bits = 8;
info->zs_channel->curregs[3] |= Rx6;
info->zs_channel->curregs[5] |= Tx6;
break;
case CS7:
bits = 9;
info->zs_channel->curregs[3] |= Rx7;
info->zs_channel->curregs[5] |= Tx7;
break;
case CS8:
default: /* defaults to 8 bits */
bits = 10;
info->zs_channel->curregs[3] |= Rx8;
info->zs_channel->curregs[5] |= Tx8;
break;
}
info->timeout = ((info->xmit_fifo_size*HZ*bits) / info->zs_baud);
info->timeout += HZ/50; /* Add .02 seconds of slop */
info->zs_channel->curregs[4] &= ~(SB_MASK | PAR_ENA | PAR_EVEN);
if (cflag & CSTOPB) {
info->zs_channel->curregs[4] |= SB2;
} else {
info->zs_channel->curregs[4] |= SB1;
}
if (cflag & PARENB) {
info->zs_channel->curregs[4] |= PAR_ENA;
}
if (!(cflag & PARODD)) {
info->zs_channel->curregs[4] |= PAR_EVEN;
}
if (!(cflag & CLOCAL)) {
if (!(info->zs_channel->curregs[15] & DCDIE))
info->read_reg_zero = read_zsreg(info->zs_channel, 0);
info->zs_channel->curregs[15] |= DCDIE;
} else
info->zs_channel->curregs[15] &= ~DCDIE;
if (cflag & CRTSCTS) {
info->zs_channel->curregs[15] |= CTSIE;
if ((read_zsreg(info->zs_channel, 0) & CTS) == 0)
info->tx_stopped = 1;
} else {
info->zs_channel->curregs[15] &= ~CTSIE;
info->tx_stopped = 0;
}
/* Load up the new values */
load_zsregs(info->zs_channel, info->zs_channel->curregs);
spin_unlock_irqrestore(&zs_lock, flags);
}
static void rs_flush_chars(struct tty_struct *tty)
{
struct dec_serial *info = (struct dec_serial *)tty->driver_data;
unsigned long flags;
if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
return;
if (info->xmit_cnt <= 0 || tty->stopped || info->tx_stopped ||
!info->xmit_buf)
return;
/* Enable transmitter */
spin_lock_irqsave(&zs_lock, flags);
transmit_chars(info);
spin_unlock_irqrestore(&zs_lock, flags);
}
static int rs_write(struct tty_struct * tty,
const unsigned char *buf, int count)
{
int c, total = 0;
struct dec_serial *info = (struct dec_serial *)tty->driver_data;
unsigned long flags;
if (serial_paranoia_check(info, tty->name, "rs_write"))
return 0;
if (!tty || !info->xmit_buf)
return 0;
while (1) {
spin_lock_irqsave(&zs_lock, flags);
c = min(count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
SERIAL_XMIT_SIZE - info->xmit_head));
if (c <= 0)
break;
memcpy(info->xmit_buf + info->xmit_head, buf, c);
info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt += c;
spin_unlock_irqrestore(&zs_lock, flags);
buf += c;
count -= c;
total += c;
}
if (info->xmit_cnt && !tty->stopped && !info->tx_stopped
&& !info->tx_active)
transmit_chars(info);
spin_unlock_irqrestore(&zs_lock, flags);
return total;
}
static int rs_write_room(struct tty_struct *tty)
{
struct dec_serial *info = (struct dec_serial *)tty->driver_data;
int ret;
if (serial_paranoia_check(info, tty->name, "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 dec_serial *info = (struct dec_serial *)tty->driver_data;
if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
return 0;
return info->xmit_cnt;
}
static void rs_flush_buffer(struct tty_struct *tty)
{
struct dec_serial *info = (struct dec_serial *)tty->driver_data;
if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
return;
spin_lock_irq(&zs_lock);
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
spin_unlock_irq(&zs_lock);
tty_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 dec_serial *info = (struct dec_serial *)tty->driver_data;
unsigned long flags;
#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->name, "rs_throttle"))
return;
if (I_IXOFF(tty)) {
spin_lock_irqsave(&zs_lock, flags);
info->x_char = STOP_CHAR(tty);
if (!info->tx_active)
transmit_chars(info);
spin_unlock_irqrestore(&zs_lock, flags);
}
if (C_CRTSCTS(tty)) {
zs_rtsdtr(info, RTS, 0);
}
}
static void rs_unthrottle(struct tty_struct * tty)
{
struct dec_serial *info = (struct dec_serial *)tty->driver_data;
unsigned long flags;
#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->name, "rs_unthrottle"))
return;
if (I_IXOFF(tty)) {
spin_lock_irqsave(&zs_lock, flags);
if (info->x_char)
info->x_char = 0;
else {
info->x_char = START_CHAR(tty);
if (!info->tx_active)
transmit_chars(info);
}
spin_unlock_irqrestore(&zs_lock, flags);
}
if (C_CRTSCTS(tty)) {
zs_rtsdtr(info, RTS, 1);
}
}
/*
* ------------------------------------------------------------
* rs_ioctl() and friends
* ------------------------------------------------------------
*/
static int get_serial_info(struct dec_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)) ? -EFAULT : 0;
}
static int set_serial_info(struct dec_serial * info,
struct serial_struct * new_info)
{
struct serial_struct new_serial;
struct dec_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 (!capable(CAP_SYS_ADMIN)) {
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 = zs_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 dec_serial * info, unsigned int *value)
{
unsigned char status;
spin_lock(&zs_lock);
status = read_zsreg(info->zs_channel, 0);
spin_unlock_irq(&zs_lock);
put_user(status,value);
return 0;
}
static int rs_tiocmget(struct tty_struct *tty, struct file *file)
{
struct dec_serial * info = (struct dec_serial *)tty->driver_data;
unsigned char control, status_a, status_b;
unsigned int result;
if (info->hook)
return -ENODEV;
if (serial_paranoia_check(info, tty->name, __FUNCTION__))
return -ENODEV;
if (tty->flags & (1 << TTY_IO_ERROR))
return -EIO;
if (info->zs_channel == info->zs_chan_a)
result = 0;
else {
spin_lock(&zs_lock);
control = info->zs_chan_a->curregs[5];
status_a = read_zsreg(info->zs_chan_a, 0);
status_b = read_zsreg(info->zs_channel, 0);
spin_unlock_irq(&zs_lock);
result = ((control & RTS) ? TIOCM_RTS: 0)
| ((control & DTR) ? TIOCM_DTR: 0)
| ((status_b & DCD) ? TIOCM_CAR: 0)
| ((status_a & DCD) ? TIOCM_RNG: 0)
| ((status_a & SYNC_HUNT) ? TIOCM_DSR: 0)
| ((status_b & CTS) ? TIOCM_CTS: 0);
}
return result;
}
static int rs_tiocmset(struct tty_struct *tty, struct file *file,
unsigned int set, unsigned int clear)
{
struct dec_serial * info = (struct dec_serial *)tty->driver_data;
if (info->hook)
return -ENODEV;
if (serial_paranoia_check(info, tty->name, __FUNCTION__))
return -ENODEV;
if (tty->flags & (1 << TTY_IO_ERROR))
return -EIO;
if (info->zs_channel == info->zs_chan_a)
return 0;
spin_lock(&zs_lock);
if (set & TIOCM_RTS)
info->zs_chan_a->curregs[5] |= RTS;
if (set & TIOCM_DTR)
info->zs_chan_a->curregs[5] |= DTR;
if (clear & TIOCM_RTS)
info->zs_chan_a->curregs[5] &= ~RTS;
if (clear & TIOCM_DTR)
info->zs_chan_a->curregs[5] &= ~DTR;
write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
spin_unlock_irq(&zs_lock);
return 0;
}
/*
* rs_break - turn transmit break condition on/off
*/
static void rs_break(struct tty_struct *tty, int break_state)
{
struct dec_serial *info = (struct dec_serial *) tty->driver_data;
unsigned long flags;
if (serial_paranoia_check(info, tty->name, "rs_break"))
return;
if (!info->port)
return;
spin_lock_irqsave(&zs_lock, flags);
if (break_state == -1)
info->zs_channel->curregs[5] |= SND_BRK;
else
info->zs_channel->curregs[5] &= ~SND_BRK;
write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
spin_unlock_irqrestore(&zs_lock, flags);
}
static int rs_ioctl(struct tty_struct *tty, struct file * file,
unsigned int cmd, unsigned long arg)
{
struct dec_serial * info = (struct dec_serial *)tty->driver_data;
if (info->hook)
return -ENODEV;
if (serial_paranoia_check(info, tty->name, "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 TIOCGSERIAL:
if (!access_ok(VERIFY_WRITE, (void *)arg,
sizeof(struct serial_struct)))
return -EFAULT;
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 */
if (!access_ok(VERIFY_WRITE, (void *)arg,
sizeof(unsigned int)))
return -EFAULT;
return get_lsr_info(info, (unsigned int *)arg);
case TIOCSERGSTRUCT:
if (!access_ok(VERIFY_WRITE, (void *)arg,
sizeof(struct dec_serial)))
return -EFAULT;
copy_from_user((struct dec_serial *)arg, info,
sizeof(struct dec_serial));
return 0;
default:
return -ENOIOCTLCMD;
}
return 0;
}
static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
{
struct dec_serial *info = (struct dec_serial *)tty->driver_data;
int was_stopped;
if (tty->termios->c_cflag == old_termios->c_cflag)
return;
was_stopped = info->tx_stopped;
change_speed(info);
if (was_stopped && !info->tx_stopped)
rs_start(tty);
}
/*
* ------------------------------------------------------------
* rs_close()
*
* This routine is called when the serial port gets closed.
* Wait for the last remaining data to be sent.
* ------------------------------------------------------------
*/
static void rs_close(struct tty_struct *tty, struct file * filp)
{
struct dec_serial * info = (struct dec_serial *)tty->driver_data;
unsigned long flags;
if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
return;
spin_lock_irqsave(&zs_lock, flags);
if (tty_hung_up_p(filp)) {
spin_unlock_irqrestore(&zs_lock, 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) {
spin_unlock_irqrestore(&zs_lock, flags);
return;
}
info->flags |= ZILOG_CLOSING;
/*
* 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 receiver and receive interrupts.
*/
info->zs_channel->curregs[3] &= ~RxENABLE;
write_zsreg(info->zs_channel, 3, info->zs_channel->curregs[3]);
info->zs_channel->curregs[1] = 0; /* disable any rx ints */
write_zsreg(info->zs_channel, 1, info->zs_channel->curregs[1]);
ZS_CLEARFIFO(info->zs_channel);
if (info->flags & ZILOG_INITIALIZED) {
/*
* Before we drop DTR, make sure the SCC transmitter
* has completely drained.
*/
rs_wait_until_sent(tty, info->timeout);
}
shutdown(info);
if (tty->driver->flush_buffer)
tty->driver->flush_buffer(tty);
tty_ldisc_flush(tty);
tty->closing = 0;
info->event = 0;
info->tty = 0;
if (info->blocked_open) {
if (info->close_delay) {
msleep_interruptible(jiffies_to_msecs(info->close_delay));
}
wake_up_interruptible(&info->open_wait);
}
info->flags &= ~(ZILOG_NORMAL_ACTIVE|ZILOG_CLOSING);
wake_up_interruptible(&info->close_wait);
spin_unlock_irqrestore(&zs_lock, flags);
}
/*
* rs_wait_until_sent() --- wait until the transmitter is empty
*/
static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
{
struct dec_serial *info = (struct dec_serial *) tty->driver_data;
unsigned long orig_jiffies;
int char_time;
if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
return;
orig_jiffies = jiffies;
/*
* Set the check interval to be 1/5 of the estimated time to
* send a single character, and make it at least 1. The check
* interval should also be less than the timeout.
*/
char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
char_time = char_time / 5;
if (char_time == 0)
char_time = 1;
if (timeout)
char_time = min(char_time, timeout);
while ((read_zsreg(info->zs_channel, 1) & Tx_BUF_EMP) == 0) {
msleep_interruptible(jiffies_to_msecs(char_time));
if (signal_pending(current))
break;
if (timeout && time_after(jiffies, orig_jiffies + timeout))
break;
}
current->state = TASK_RUNNING;
}
/*
* rs_hangup() --- called by tty_hangup() when a hangup is signaled.
*/
static void rs_hangup(struct tty_struct *tty)
{
struct dec_serial * info = (struct dec_serial *)tty->driver_data;
if (serial_paranoia_check(info, tty->name, "rs_hangup"))
return;
rs_flush_buffer(tty);
shutdown(info);
info->event = 0;
info->count = 0;
info->flags &= ~ZILOG_NORMAL_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 dec_serial *info)
{
DECLARE_WAITQUEUE(wait, current);
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
return ((info->flags & ZILOG_HUP_NOTIFY) ?
-EAGAIN : -ERESTARTSYS);
#else
return -EAGAIN;
#endif
}
/*
* 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))) {
info->flags |= ZILOG_NORMAL_ACTIVE;
return 0;
}
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
spin_lock(&zs_lock);
if (!tty_hung_up_p(filp))
info->count--;
spin_unlock_irq(&zs_lock);
info->blocked_open++;
while (1) {
spin_lock(&zs_lock);
if (tty->termios->c_cflag & CBAUD)
zs_rtsdtr(info, RTS | DTR, 1);
spin_unlock_irq(&zs_lock);
set_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_CLOSING) &&
(do_clocal || (read_zsreg(info->zs_channel, 0) & DCD)))
break;
if (signal_pending(current)) {
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.
*/
static int rs_open(struct tty_struct *tty, struct file * filp)
{
struct dec_serial *info;
int retval, line;
line = tty->index;
if ((line < 0) || (line >= zs_channels_found))
return -ENODEV;
info = zs_soft + line;
if (info->hook)
return -ENODEV;
if (serial_paranoia_check(info, tty->name, "rs_open"))
return -ENODEV;
#ifdef SERIAL_DEBUG_OPEN
printk("rs_open %s, count = %d\n", tty->name, info->count);
#endif
info->count++;
tty->driver_data = info;
info->tty = tty;
/*
* If the port is the middle of closing, bail out now
*/
if (tty_hung_up_p(filp) ||
(info->flags & ZILOG_CLOSING)) {
if (info->flags & ZILOG_CLOSING)
interruptible_sleep_on(&info->close_wait);
#ifdef SERIAL_DO_RESTART
return ((info->flags & ZILOG_HUP_NOTIFY) ?
-EAGAIN : -ERESTARTSYS);
#else
return -EAGAIN;
#endif
}
/*
* Start up serial port
*/
retval = zs_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;
}
#ifdef CONFIG_SERIAL_DEC_CONSOLE
if (sercons.cflag && sercons.index == line) {
tty->termios->c_cflag = sercons.cflag;
sercons.cflag = 0;
change_speed(info);
}
#endif
#ifdef SERIAL_DEBUG_OPEN
printk("rs_open %s successful...", tty->name);
#endif
/* tty->low_latency = 1; */
return 0;
}
/* Finally, routines used to initialize the serial driver. */
static void __init show_serial_version(void)
{
printk("DECstation Z8530 serial driver version 0.09\n");
}
/* Initialize Z8530s zs_channels
*/
static void __init probe_sccs(void)
{
struct dec_serial **pp;
int i, n, n_chips = 0, n_channels, chip, channel;
unsigned long flags;
/*
* did we get here by accident?
*/
if(!BUS_PRESENT) {
printk("Not on JUNKIO machine, skipping probe_sccs\n");
return;
}
switch(mips_machtype) {
#ifdef CONFIG_MACH_DECSTATION
case MACH_DS5000_2X0:
case MACH_DS5900:
n_chips = 2;
zs_parms = &ds_parms;
zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
zs_parms->irq1 = dec_interrupt[DEC_IRQ_SCC1];
break;
case MACH_DS5000_1XX:
n_chips = 2;
zs_parms = &ds_parms;
zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
zs_parms->irq1 = dec_interrupt[DEC_IRQ_SCC1];
break;
case MACH_DS5000_XX:
n_chips = 1;
zs_parms = &ds_parms;
zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
break;
#endif
default:
panic("zs: unsupported bus");
}
if (!zs_parms)
panic("zs: uninitialized parms");
pp = &zs_chain;
n_channels = 0;
for (chip = 0; chip < n_chips; chip++) {
for (channel = 0; channel <= 1; channel++) {
/*
* The sccs reside on the high byte of the 16 bit IOBUS
*/
zs_channels[n_channels].control =
(volatile void *)CKSEG1ADDR(dec_kn_slot_base +
(0 == chip ? zs_parms->scc0 : zs_parms->scc1) +
(0 == channel ? zs_parms->channel_a_offset :
zs_parms->channel_b_offset));
zs_channels[n_channels].data =
zs_channels[n_channels].control + 4;
#ifndef CONFIG_SERIAL_DEC_CONSOLE
/*
* We're called early and memory managment isn't up, yet.
* Thus request_region would fail.
*/
if (!request_region((unsigned long)
zs_channels[n_channels].control,
ZS_CHAN_IO_SIZE, "SCC"))
panic("SCC I/O region is not free");
#endif
zs_soft[n_channels].zs_channel = &zs_channels[n_channels];
/* HACK alert! */
if (!(chip & 1))
zs_soft[n_channels].irq = zs_parms->irq0;
else
zs_soft[n_channels].irq = zs_parms->irq1;
/*
* Identification of channel A. Location of channel A
* inside chip depends on mapping of internal address
* the chip decodes channels by.
* CHANNEL_A_NR returns either 0 (in case of
* DECstations) or 1 (in case of Baget).
*/
if (CHANNEL_A_NR == channel)
zs_soft[n_channels].zs_chan_a =
&zs_channels[n_channels+1-2*CHANNEL_A_NR];
else
zs_soft[n_channels].zs_chan_a =
&zs_channels[n_channels];
*pp = &zs_soft[n_channels];
pp = &zs_soft[n_channels].zs_next;
n_channels++;
}
}
*pp = 0;
zs_channels_found = n_channels;
for (n = 0; n < zs_channels_found; n++) {
for (i = 0; i < 16; i++) {
zs_soft[n].zs_channel->curregs[i] = zs_init_regs[i];
}
}
spin_lock_irqsave(&zs_lock, flags);
for (n = 0; n < zs_channels_found; n++) {
if (n % 2 == 0) {
write_zsreg(zs_soft[n].zs_chan_a, R9, FHWRES);
udelay(10);
write_zsreg(zs_soft[n].zs_chan_a, R9, 0);
}
load_zsregs(zs_soft[n].zs_channel,
zs_soft[n].zs_channel->curregs);
}
spin_unlock_irqrestore(&zs_lock, flags);
}
static const struct tty_operations serial_ops = {
.open = rs_open,
.close = rs_close,
.write = rs_write,
.flush_chars = rs_flush_chars,
.write_room = rs_write_room,
.chars_in_buffer = rs_chars_in_buffer,
.flush_buffer = rs_flush_buffer,
.ioctl = rs_ioctl,
.throttle = rs_throttle,
.unthrottle = rs_unthrottle,
.set_termios = rs_set_termios,
.stop = rs_stop,
.start = rs_start,
.hangup = rs_hangup,
.break_ctl = rs_break,
.wait_until_sent = rs_wait_until_sent,
.tiocmget = rs_tiocmget,
.tiocmset = rs_tiocmset,
};
/* zs_init inits the driver */
int __init zs_init(void)
{
int channel, i;
struct dec_serial *info;
if(!BUS_PRESENT)
return -ENODEV;
/* Find out how many Z8530 SCCs we have */
if (zs_chain == 0)
probe_sccs();
serial_driver = alloc_tty_driver(zs_channels_found);
if (!serial_driver)
return -ENOMEM;
show_serial_version();
/* Initialize the tty_driver structure */
/* Not all of this is exactly right for us. */
serial_driver->owner = THIS_MODULE;
serial_driver->name = "ttyS";
serial_driver->major = TTY_MAJOR;
serial_driver->minor_start = 64;
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 | TTY_DRIVER_DYNAMIC_DEV;
tty_set_operations(serial_driver, &serial_ops);
if (tty_register_driver(serial_driver))
panic("Couldn't register serial driver");
for (info = zs_chain, i = 0; info; info = info->zs_next, i++) {
/* Needed before interrupts are enabled. */
info->tty = 0;
info->x_char = 0;
if (info->hook && info->hook->init_info) {
(*info->hook->init_info)(info);
continue;
}
info->magic = SERIAL_MAGIC;
info->port = (int) info->zs_channel->control;
info->line = i;
info->custom_divisor = 16;
info->close_delay = 50;
info->closing_wait = 3000;
info->event = 0;
info->count = 0;
info->blocked_open = 0;
tasklet_init(&info->tlet, do_softint, (unsigned long)info);
init_waitqueue_head(&info->open_wait);
init_waitqueue_head(&info->close_wait);
printk("ttyS%02d at 0x%08x (irq = %d) is a Z85C30 SCC\n",
info->line, info->port, info->irq);
tty_register_device(serial_driver, info->line, NULL);
}
for (channel = 0; channel < zs_channels_found; ++channel) {
zs_soft[channel].clk_divisor = 16;
zs_soft[channel].zs_baud = get_zsbaud(&zs_soft[channel]);
if (request_irq(zs_soft[channel].irq, rs_interrupt, IRQF_SHARED,
"scc", &zs_soft[channel]))
printk(KERN_ERR "decserial: can't get irq %d\n",
zs_soft[channel].irq);
if (zs_soft[channel].hook) {
zs_startup(&zs_soft[channel]);
if (zs_soft[channel].hook->init_channel)
(*zs_soft[channel].hook->init_channel)
(&zs_soft[channel]);
}
}
return 0;
}
/*
* polling I/O routines
*/
static int zs_poll_tx_char(void *handle, unsigned char ch)
{
struct dec_serial *info = handle;
struct dec_zschannel *chan = info->zs_channel;
int ret;
if(chan) {
int loops = 10000;
while (loops && !(read_zsreg(chan, 0) & Tx_BUF_EMP))
loops--;
if (loops) {
write_zsdata(chan, ch);
ret = 0;
} else
ret = -EAGAIN;
return ret;
} else
return -ENODEV;
}
static int zs_poll_rx_char(void *handle)
{
struct dec_serial *info = handle;
struct dec_zschannel *chan = info->zs_channel;
int ret;
if(chan) {
int loops = 10000;
while (loops && !(read_zsreg(chan, 0) & Rx_CH_AV))
loops--;
if (loops)
ret = read_zsdata(chan);
else
ret = -EAGAIN;
return ret;
} else
return -ENODEV;
}
int register_zs_hook(unsigned int channel, struct dec_serial_hook *hook)
{
struct dec_serial *info = &zs_soft[channel];
if (info->hook) {
printk("%s: line %d has already a hook registered\n",
__FUNCTION__, channel);
return 0;
} else {
hook->poll_rx_char = zs_poll_rx_char;
hook->poll_tx_char = zs_poll_tx_char;
info->hook = hook;
return 1;
}
}
int unregister_zs_hook(unsigned int channel)
{
struct dec_serial *info = &zs_soft[channel];
if (info->hook) {
info->hook = NULL;
return 1;
} else {
printk("%s: trying to unregister hook on line %d,"
" but none is registered\n", __FUNCTION__, channel);
return 0;
}
}
/*
* ------------------------------------------------------------
* Serial console driver
* ------------------------------------------------------------
*/
#ifdef CONFIG_SERIAL_DEC_CONSOLE
/*
* Print a string to the serial port trying not to disturb
* any possible real use of the port...
*/
static void serial_console_write(struct console *co, const char *s,
unsigned count)
{
struct dec_serial *info;
int i;
info = zs_soft + co->index;
for (i = 0; i < count; i++, s++) {
if(*s == '\n')
zs_poll_tx_char(info, '\r');
zs_poll_tx_char(info, *s);
}
}
static struct tty_driver *serial_console_device(struct console *c, int *index)
{
*index = c->index;
return serial_driver;
}
/*
* Setup initial baud/bits/parity. We do two things here:
* - construct a cflag setting for the first rs_open()
* - initialize the serial port
* Return non-zero if we didn't find a serial port.
*/
static int __init serial_console_setup(struct console *co, char *options)
{
struct dec_serial *info;
int baud = 9600;
int bits = 8;
int parity = 'n';
int cflag = CREAD | HUPCL | CLOCAL;
int clk_divisor = 16;
int brg;
char *s;
unsigned long flags;
if(!BUS_PRESENT)
return -ENODEV;
info = zs_soft + co->index;
if (zs_chain == 0)
probe_sccs();
info->is_cons = 1;
if (options) {
baud = simple_strtoul(options, NULL, 10);
s = options;
while(*s >= '0' && *s <= '9')
s++;
if (*s)
parity = *s++;
if (*s)
bits = *s - '0';
}
/*
* Now construct a cflag setting.
*/
switch(baud) {
case 1200:
cflag |= B1200;
break;
case 2400:
cflag |= B2400;
break;
case 4800:
cflag |= B4800;
break;
case 19200:
cflag |= B19200;
break;
case 38400:
cflag |= B38400;
break;
case 57600:
cflag |= B57600;
break;
case 115200:
cflag |= B115200;
break;
case 9600:
default:
cflag |= B9600;
/*
* Set this to a sane value to prevent a divide error.
*/
baud = 9600;
break;
}
switch(bits) {
case 7:
cflag |= CS7;
break;
default:
case 8:
cflag |= CS8;
break;
}
switch(parity) {
case 'o': case 'O':
cflag |= PARODD;
break;
case 'e': case 'E':
cflag |= PARENB;
break;
}
co->cflag = cflag;
spin_lock_irqsave(&zs_lock, flags);
/*
* Set up the baud rate generator.
*/
brg = BPS_TO_BRG(baud, zs_parms->clock / clk_divisor);
info->zs_channel->curregs[R12] = (brg & 255);
info->zs_channel->curregs[R13] = ((brg >> 8) & 255);
/*
* Set byte size and parity.
*/
if (bits == 7) {
info->zs_channel->curregs[R3] |= Rx7;
info->zs_channel->curregs[R5] |= Tx7;
} else {
info->zs_channel->curregs[R3] |= Rx8;
info->zs_channel->curregs[R5] |= Tx8;
}
if (cflag & PARENB) {
info->zs_channel->curregs[R4] |= PAR_ENA;
}
if (!(cflag & PARODD)) {
info->zs_channel->curregs[R4] |= PAR_EVEN;
}
info->zs_channel->curregs[R4] |= SB1;
/*
* Turn on RTS and DTR.
*/
zs_rtsdtr(info, RTS | DTR, 1);
/*
* Finally, enable sequencing.
*/
info->zs_channel->curregs[R3] |= RxENABLE;
info->zs_channel->curregs[R5] |= TxENAB;
/*
* Clear the interrupt registers.
*/
write_zsreg(info->zs_channel, R0, ERR_RES);
write_zsreg(info->zs_channel, R0, RES_H_IUS);
/*
* Load up the new values.
*/
load_zsregs(info->zs_channel, info->zs_channel->curregs);
/* Save the current value of RR0 */
info->read_reg_zero = read_zsreg(info->zs_channel, R0);
zs_soft[co->index].clk_divisor = clk_divisor;
zs_soft[co->index].zs_baud = get_zsbaud(&zs_soft[co->index]);
spin_unlock_irqrestore(&zs_lock, flags);
return 0;
}
static struct console sercons = {
.name = "ttyS",
.write = serial_console_write,
.device = serial_console_device,
.setup = serial_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
};
/*
* Register console.
*/
void __init zs_serial_console_init(void)
{
register_console(&sercons);
}
#endif /* ifdef CONFIG_SERIAL_DEC_CONSOLE */
#ifdef CONFIG_KGDB
struct dec_zschannel *zs_kgdbchan;
static unsigned char scc_inittab[] = {
9, 0x80, /* reset A side (CHRA) */
13, 0, /* set baud rate divisor */
12, 1,
14, 1, /* baud rate gen enable, src=rtxc (BRENABL) */
11, 0x50, /* clocks = br gen (RCBR | TCBR) */
5, 0x6a, /* tx 8 bits, assert RTS (Tx8 | TxENAB | RTS) */
4, 0x44, /* x16 clock, 1 stop (SB1 | X16CLK)*/
3, 0xc1, /* rx enable, 8 bits (RxENABLE | Rx8)*/
};
/* These are for receiving and sending characters under the kgdb
* source level kernel debugger.
*/
void putDebugChar(char kgdb_char)
{
struct dec_zschannel *chan = zs_kgdbchan;
while ((read_zsreg(chan, 0) & Tx_BUF_EMP) == 0)
RECOVERY_DELAY;
write_zsdata(chan, kgdb_char);
}
char getDebugChar(void)
{
struct dec_zschannel *chan = zs_kgdbchan;
while((read_zsreg(chan, 0) & Rx_CH_AV) == 0)
eieio(); /*barrier();*/
return read_zsdata(chan);
}
void kgdb_interruptible(int yes)
{
struct dec_zschannel *chan = zs_kgdbchan;
int one, nine;
nine = read_zsreg(chan, 9);
if (yes == 1) {
one = EXT_INT_ENAB|RxINT_ALL;
nine |= MIE;
printk("turning serial ints on\n");
} else {
one = RxINT_DISAB;
nine &= ~MIE;
printk("turning serial ints off\n");
}
write_zsreg(chan, 1, one);
write_zsreg(chan, 9, nine);
}
static int kgdbhook_init_channel(void *handle)
{
return 0;
}
static void kgdbhook_init_info(void *handle)
{
}
static void kgdbhook_rx_char(void *handle, unsigned char ch, unsigned char fl)
{
struct dec_serial *info = handle;
if (fl != TTY_NORMAL)
return;
if (ch == 0x03 || ch == '$')
breakpoint();
}
/* This sets up the serial port we're using, and turns on
* interrupts for that channel, so kgdb is usable once we're done.
*/
static inline void kgdb_chaninit(struct dec_zschannel *ms, int intson, int bps)
{
int brg;
int i, x;
volatile char *sccc = ms->control;
brg = BPS_TO_BRG(bps, zs_parms->clock/16);
printk("setting bps on kgdb line to %d [brg=%x]\n", bps, brg);
for (i = 20000; i != 0; --i) {
x = *sccc; eieio();
}
for (i = 0; i < sizeof(scc_inittab); ++i) {
write_zsreg(ms, scc_inittab[i], scc_inittab[i+1]);
i++;
}
}
/* This is called at boot time to prime the kgdb serial debugging
* serial line. The 'tty_num' argument is 0 for /dev/ttya and 1
* for /dev/ttyb which is determined in setup_arch() from the
* boot command line flags.
*/
struct dec_serial_hook zs_kgdbhook = {
.init_channel = kgdbhook_init_channel,
.init_info = kgdbhook_init_info,
.rx_char = kgdbhook_rx_char,
.cflags = B38400 | CS8 | CLOCAL,
}
void __init zs_kgdb_hook(int tty_num)
{
/* Find out how many Z8530 SCCs we have */
if (zs_chain == 0)
probe_sccs();
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 = 38400;
zs_soft[tty_num].hook = &zs_kgdbhook; /* This runs kgdb */
/* Turn on transmitter/receiver at 8-bits/char */
kgdb_chaninit(zs_soft[tty_num].zs_channel, 1, 38400);
printk("KGDB: on channel %d initialized\n", tty_num);
set_debug_traps(); /* init stub */
}
#endif /* ifdef CONFIG_KGDB */
