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kernel / pub / scm / linux / kernel / git / wtarreau / linux-2.4 / refs/heads/master / . / drivers / char / sgiserial.c
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/* sgiserial.c: Serial port driver for SGI machines.
*
* Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
*/
/*
* Note: This driver seems to have been derived from some
* version of the sbus/char/zs.c driver. A lot of clean-up
* and bug fixes seem to have happened to the Sun driver in
* the intervening time. As of 21.09.1999, I have merged in
* ONLY the changes necessary to fix observed functional
* problems on the Indy. Someone really ought to do a
* thorough pass to merge in the rest of the updates.
* Better still, someone really ought to make it a common
* code module for both platforms. kevink@mips.com
*/
#include <linux/config.h> /* for CONFIG_KGDB */
#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/console.h>
#include <linux/init.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <asm/uaccess.h>
#include <asm/sgialib.h>
#include <asm/sgi/ioc.h>
#include <asm/sgi/ip22.h>
#include "sgiserial.h"
#define NUM_SERIAL 1 /* One chip on board. */
#define NUM_CHANNELS (NUM_SERIAL * 2)
struct sgi_zslayout *zs_chips[NUM_SERIAL];
struct sgi_zschannel *zs_channels[NUM_CHANNELS];
struct sgi_zschannel *zs_conschan;
struct sgi_zschannel *zs_kgdbchan;
struct sgi_serial zs_soft[NUM_CHANNELS];
struct sgi_serial *zs_chain; /* IRQ servicing chain */
static int zilog_irq = SGI_SERIAL_IRQ;
/* Console hooks... */
static int zs_cons_chanout;
static int zs_cons_chanin;
struct sgi_serial *zs_consinfo;
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 */
};
static unsigned char zscons_regs[16] = {
0, /* write 0 */
(EXT_INT_ENAB | INT_ALL_Rx), /* write 1 */
0, /* write 2 */
(Rx8 | RxENABLE), /* write 3 */
(X16CLK), /* write 4 */
(DTR | Tx8 | TxENAB), /* write 5 */
0, 0, 0, /* write 6, 7, 8 */
(NV | MIE), /* write 9 */
(NRZ), /* write 10 */
(TCBR | RCBR), /* write 11 */
0, 0, /* BRG time constant, write 12 + 13 */
(BRENABL), /* write 14 */
(DCDIE | CTSIE | TxUIE | BRKIE) /* write 15 */
};
#define ZS_CLOCK 3672000 /* Zilog input clock rate */
DECLARE_TASK_QUEUE(tq_serial);
struct tty_driver serial_driver, callout_driver;
struct console *sgisercon;
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
#undef SERIAL_DEBUG_OPEN
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];
/*
* 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[PAGE_SIZE]; /* This is cheating */
static DECLARE_MUTEX(tmp_buf_sem);
static inline int serial_paranoia_check(struct sgi_serial *info,
dev_t device, const char *routine)
{
#ifdef SERIAL_PARANOIA_CHECK
static const char *badmagic = KERN_WARNING
"Warning: bad magic number for serial struct (%d, %d) in %s\n";
static const char *badinfo = KERN_WARNING
"Warning: null sgi_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.
*
* read_zsreg() and write_zsreg() may get called from rs_kgdb_hook() before
* interrupts are enabled. Therefore we have to check ioc_iocontrol before we
* access it.
*/
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 = sgint->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 = sgint->istat0;
udelay(1);
channel->control = value;
junk = sgint->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);
write_zsreg(ss->zs_channel, 5, ss->curregs[5]);
} else {
ss->curregs[5] &= ~(RTS | DTR);
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/ss->clk_divisor);
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;
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;
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)
{
ArcEnterInteractiveMode();
#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 = sgint->istat0;
udelay(2);
zsc->control = RES_H_IUS;
junk = sgint->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_KGDB
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 = sgint->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;
}
}
/* 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_KGDB
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 zs_cons_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 = sgint->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 = sgint->istat0;
goto clear_and_return;
}
/* Send char */
udelay(2);
info->zs_channel->data = info->xmit_buf[info->xmit_tail++];
junk = sgint->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 = sgint->istat0;
goto clear_and_return;
}
clear_and_return:
/* Clear interrupt */
udelay(2);
info->zs_channel->control = RES_H_IUS;
junk = sgint->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 = sgint->istat0;
/* Clear status condition... */
udelay(2);
info->zs_channel->control = RES_EXT_INT;
junk = sgint->istat0;
/* Clear the interrupt */
udelay(2);
info->zs_channel->control = RES_H_IUS;
junk = sgint->istat0;
#if 0
if(status & DCD) {
if((info->tty->termios->c_cflag & CRTSCTS) &&
((info->curregs[3] & AUTO_ENAB)==0)) {
info->curregs[3] |= AUTO_ENAB;
write_zsreg(info->zs_channel, 3, info->curregs[3]);
}
} else {
if((info->curregs[3] & AUTO_ENAB)) {
info->curregs[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_next->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 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);
}
info=info->zs_next;
/* 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);
}
}
/*
* -------------------------------------------------------------------
* 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);
}
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)...\n", 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 = sgint->istat0;
udelay(2);
info->zs_channel->control = RES_H_IUS;
junk = sgint->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->curregs[3] |= (RxENABLE | Rx8);
/* We enable Tx interrupts as needed. */
info->curregs[5] |= (TxENAB | Tx8);
info->curregs[9] |= (NV | MIE);
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 = sgint->istat0;
udelay(2);
info->zs_channel->control = RES_H_IUS;
junk = sgint->istat0;
if (info->tty)
clear_bit(TTY_IO_ERROR, &info->tty->flags);
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
/*
* 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 int port, 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->curregs[5] &= ~(0xe0);
info->curregs[5] |= Tx5;
break;
case CS6:
info->curregs[3] &= ~(0xc0);
info->curregs[3] |= Rx6;
info->curregs[5] &= ~(0xe0);
info->curregs[5] |= Tx6;
break;
case CS7:
info->curregs[3] &= ~(0xc0);
info->curregs[3] |= Rx7;
info->curregs[5] &= ~(0xe0);
info->curregs[5] |= Tx7;
break;
case CS8:
default: /* defaults to 8 bits */
info->curregs[3] &= ~(0xc0);
info->curregs[3] |= Rx8;
info->curregs[5] &= ~(0xe0);
info->curregs[5] |= Tx8;
break;
}
info->curregs[4] &= ~(0x0c);
if (cflag & CSTOPB)
info->curregs[4] |= SB2;
else
info->curregs[4] |= SB1;
if (cflag & PARENB)
info->curregs[4] |= PAR_ENA;
else
info->curregs[4] &= ~PAR_ENA;
if (!(cflag & PARODD))
info->curregs[4] |= PAR_EVEN;
else
info->curregs[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 zs_cons_put_char(char ch)
{
struct sgi_zschannel *chan = zs_conschan;
volatile unsigned char junk;
unsigned long flags;
int 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 = sgint->istat0;
restore_flags(flags);
}
/*
* This is the more generic put_char function for the driver.
* In earlier versions of this driver, "rs_put_char" was the
* name of the console-specific fucntion, now called zs_cons_put_char
*/
static void rs_put_char(struct tty_struct *tty, char ch)
{
struct sgi_zschannel *chan =
((struct sgi_serial *)tty->driver_data)->zs_channel;
volatile unsigned char junk;
unsigned long flags;
int 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 = sgint->istat0;
restore_flags(flags);
}
/* These are for receiving and sending characters under the kgdb
* source level kernel debugger.
*/
int 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 = sgint->istat0;
restore_flags(flags);
return 1;
}
char getDebugChar(void)
{
struct sgi_zschannel *chan = zs_kgdbchan;
unsigned char junk;
while((chan->control & Rx_CH_AV)==0)
udelay(2);
junk = sgint->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);
zs_cons_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 = sgint->istat0;
restore_flags(flags);
return;
}
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) {
/*
* The above test used to include the condition
* "&& !(info->curregs[5] & TxENAB)", but there
* is reason to suspect that it is never statisfied
* when the port is running. The problem may in fact
* have been masked by the fact that, if O_POST is set,
* there is always a rs_flush_xx operation following the
* rs_write, and the flush ignores that condition when
* it kicks off the transmit.
*/
/* Enable transmitter */
info->curregs[1] |= TxINT_ENAB|EXT_INT_ENAB;
write_zsreg(info->zs_channel, 1, info->curregs[1]);
info->curregs[5] |= TxENAB;
write_zsreg(info->zs_channel, 5, info->curregs[5]);
/*
* The following code is imported from the 2.3.6 Sun sbus zs.c
* driver, of which an earlier version served as the basis
* for sgiserial.c. Perhaps due to changes over time in
* the line discipline code, ns_write()s with from_user
* set would not otherwise actually kick-off output in
* Linux 2.2.x or later. Maybe it never really worked.
*/
rs_put_char(tty, info->xmit_buf[info->xmit_tail++]);
info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt--;
}
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);
}
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;
write_zsreg(info->zs_channel, 1, info->curregs[1]);
info->curregs[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 = sgint->istat0;
info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
info->xmit_cnt--;
}
restore_flags(flags);
}
/*
* ------------------------------------------------------------
* 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;
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;
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)) ? -EFAULT : 0;
}
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 (!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 = 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 = sgint->istat0;
sti();
return put_user(status,value);
}
static int get_modem_info(struct sgi_serial * info, unsigned int *value)
{
unsigned char status;
unsigned int result;
cli();
status = info->zs_channel->control;
udelay(2);
sti();
result = ((info->curregs[5] & RTS) ? TIOCM_RTS : 0)
| ((info->curregs[5] & DTR) ? TIOCM_DTR : 0)
| ((status & DCD) ? TIOCM_CAR : 0)
| ((status & SYNC) ? TIOCM_DSR : 0)
| ((status & CTS) ? TIOCM_CTS : 0);
if (put_user(result, value))
return -EFAULT;
return 0;
}
static int set_modem_info(struct sgi_serial * info, unsigned int cmd,
unsigned int *value)
{
unsigned int arg;
if (get_user(arg, value))
return -EFAULT;
switch (cmd) {
case TIOCMBIS:
if (arg & TIOCM_RTS)
info->curregs[5] |= RTS;
if (arg & TIOCM_DTR)
info->curregs[5] |= DTR;
break;
case TIOCMBIC:
if (arg & TIOCM_RTS)
info->curregs[5] &= ~RTS;
if (arg & TIOCM_DTR)
info->curregs[5] &= ~DTR;
break;
case TIOCMSET:
info->curregs[5] = ((info->curregs[5] & ~(RTS | DTR))
| ((arg & TIOCM_RTS) ? RTS : 0)
| ((arg & TIOCM_DTR) ? DTR : 0));
break;
default:
return -EINVAL;
}
cli();
write_zsreg(info->zs_channel, 5, info->curregs[5]);
sti();
return 0;
}
/*
* 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;
cli();
write_zsreg(info->zs_channel, 5, (info->curregs[5] | SND_BRK));
schedule_timeout(duration);
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)
{
struct sgi_serial * info = (struct sgi_serial *) tty->driver_data;
int retval;
if (serial_paranoia_check(info, tty->device, "zs_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:
if (put_user(C_CLOCAL(tty) ? 1 : 0,
(unsigned long *) arg))
return -EFAULT;
return 0;
case TIOCSSOFTCAR:
if (get_user(arg, (unsigned long *) arg))
return -EFAULT;
tty->termios->c_cflag =
((tty->termios->c_cflag & ~CLOCAL) |
(arg ? CLOCAL : 0));
return 0;
case TIOCMGET:
return get_modem_info(info, (unsigned int *) arg);
case TIOCMBIS:
case TIOCMBIC:
case TIOCMSET:
return set_modem_info(info, cmd, (unsigned int *) arg);
case TIOCGSERIAL:
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 */
return get_lsr_info(info, (unsigned int *) arg);
case TIOCSERGSTRUCT:
if (copy_to_user((struct sgi_serial *) arg,
info, sizeof(struct sgi_serial)))
return -EFAULT;
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;
write_zsreg(info->zs_channel, 3, info->curregs[3]);
info->curregs[1] &= ~(0x18);
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 != N_TTY) {
if (tty->ldisc.close)
(tty->ldisc.close)(tty);
tty->ldisc = *(tty_ldisc_get(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;
schedule_timeout(info->close_delay);
}
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)
{
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
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();
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_CALLOUT_ACTIVE) &&
!(info->flags & ZILOG_CLOSING) && do_clocal)
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.
*/
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);
}
/* If this is the serial console change the speed to
* the right value
*/
if (info->is_cons) {
info->tty->termios->c_cflag = sgisercon->cflag;
change_speed(info);
}
info->session = current->session;
info->pgrp = current->pgrp;
#ifdef SERIAL_DEBUG_OPEN
printk("rs_open ttys%d successful...\n", 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)
{
if (chip > 0)
panic("Wheee, bogus zs chip number requested.");
return (struct sgi_zslayout *) (&sgioc->serport);
}
static inline void
rs_cons_check(struct sgi_serial *ss, int channel)
{
int i, o, io;
static int 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;
/* 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;
/* 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")));
}
}
/* rs_init inits the driver */
int rs_init(void)
{
unsigned long flags;
int chip, channel, i;
struct sgi_serial *info;
/* Setup base handler, and timer table. */
init_bh(SERIAL_BH, do_serial_bh);
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;
#ifdef CONFIG_DEVFS_FS
serial_driver.name = "tts/%d";
#else
serial_driver.name = "ttyS";
#endif
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;
#ifdef CONFIG_DEVFS_FS
callout_driver.name = "cua/%d";
#else
callout_driver.name = "cua";
#endif
callout_driver.major = TTYAUX_MAJOR;
callout_driver.subtype = SERIAL_TYPE_CALLOUT;
if (tty_register_driver(&serial_driver))
panic("Couldn't register serial driver");
if (tty_register_driver(&callout_driver))
panic("Couldn't register callout driver");
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]->channelB;
zs_channels[(chip*2)+1] = &zs_chips[chip]->channelA;
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;
init_waitqueue_head(&info->open_wait);
init_waitqueue_head(&info->close_wait);
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");
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 != 0 && line != 1)
panic("rs_cons_hook called with line not ttya or ttyb");
channel = line;
if(!zs_chips[chip]) {
zs_chips[chip] = get_zs(chip);
/* Two channels per chip */
zs_channels[(chip*2)] = &zs_chips[chip]->channelB;
zs_channels[(chip*2)+1] = &zs_chips[chip]->channelA;
}
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);
}
static void zs_console_write(struct console *co, const char *str,
unsigned int count)
{
while(count--) {
if(*str == '\n')
zs_cons_put_char('\r');
zs_cons_put_char(*str++);
}
/* Comment this if you want to have a strict interrupt-driven output */
rs_fair_output();
}
static kdev_t zs_console_device(struct console *con)
{
return MKDEV(TTY_MAJOR, 64 + con->index);
}
static int __init zs_console_setup(struct console *con, char *options)
{
struct sgi_serial *info;
int baud = 9600;
int bits = 8;
int parity = 'n';
int cflag = CREAD | HUPCL | CLOCAL;
char *s;
int i, brg;
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;
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;
}
con->cflag = cflag;
rs_cons_hook(0, 0, con->index);
info = zs_soft + con->index;
info->is_cons = 1;
printk("Console: ttyS%d (Zilog8530), %d baud\n",
info->line, baud);
i = con->cflag & CBAUD;
if (con->cflag & CBAUDEX) {
i &= ~CBAUDEX;
con->cflag &= ~CBAUDEX;
}
info->zs_baud = baud;
switch (con->cflag & CSIZE) {
case CS5:
zscons_regs[3] = Rx5 | RxENABLE;
zscons_regs[5] = Tx5 | TxENAB;
break;
case CS6:
zscons_regs[3] = Rx6 | RxENABLE;
zscons_regs[5] = Tx6 | TxENAB;
break;
case CS7:
zscons_regs[3] = Rx7 | RxENABLE;
zscons_regs[5] = Tx7 | TxENAB;
break;
default:
case CS8:
zscons_regs[3] = Rx8 | RxENABLE;
zscons_regs[5] = Tx8 | TxENAB;
break;
}
zscons_regs[5] |= DTR;
if (con->cflag & PARENB)
zscons_regs[4] |= PAR_ENA;
if (!(con->cflag & PARODD))
zscons_regs[4] |= PAR_EVEN;
if (con->cflag & CSTOPB)
zscons_regs[4] |= SB2;
else
zscons_regs[4] |= SB1;
sgisercon = con;
brg = BPS_TO_BRG(baud, ZS_CLOCK / info->clk_divisor);
zscons_regs[12] = brg & 0xff;
zscons_regs[13] = (brg >> 8) & 0xff;
memcpy(info->curregs, zscons_regs, sizeof(zscons_regs));
load_zsregs(info->zs_channel, zscons_regs);
ZS_CLEARERR(info->zs_channel);
ZS_CLEARFIFO(info->zs_channel);
return 0;
}
static struct console sgi_console_driver = {
.name = "ttyS",
.write = zs_console_write,
.device = zs_console_device,
.setup = zs_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
};
/*
* Register console.
*/
void __init sgi_serial_console_init(void)
{
register_console(&sgi_console_driver);
}
__initcall(rs_init);