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
- *
- * 20010616 - Klaus Naumann <spock@mgnet.de> : Make serial console work with
- * any speed - not only 9600
- */
- #include <linux/config.h> /* for CONFIG_REMOTE_DEBUG */
- #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/sgialib.h>
- #include <asm/system.h>
- #include <asm/bitops.h>
- #include <asm/sgi/sgihpc.h>
- #include <asm/sgi/sgint23.h>
- #include <asm/uaccess.h>
- #include "sgiserial.h"
- #define NUM_SERIAL 1 /* One chip on board. */
- #define NUM_CHANNELS (NUM_SERIAL * 2)
- extern wait_queue_head_t keypress_wait;
- struct sgi_zslayout *zs_chips[NUM_SERIAL] = { 0, };
- struct sgi_zschannel *zs_channels[NUM_CHANNELS] = { 0, 0, };
- struct sgi_zschannel *zs_conschan;
- struct sgi_zschannel *zs_kgdbchan;
- 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
- /* Debugging... DEBUG_INTR is bad to use when one of the zs
- * lines is your console ;(
- */
- #undef SERIAL_DEBUG_INTR
- #undef SERIAL_DEBUG_OPEN
- #undef SERIAL_DEBUG_FLOW
- #define RS_STROBE_TIME 10
- #define RS_ISR_PASS_LIMIT 256
- #define _INLINE_ inline
- static void change_speed(struct sgi_serial *info);
- static struct tty_struct *serial_table[NUM_CHANNELS];
- static struct termios *serial_termios[NUM_CHANNELS];
- static struct termios *serial_termios_locked[NUM_CHANNELS];
- #ifndef MIN
- #define MIN(a,b) ((a) < (b) ? (a) : (b))
- #endif
- /*
- * tmp_buf is used as a temporary buffer by serial_write. We need to
- * lock it in case the memcpy_fromfs blocks while swapping in a page,
- * and some other program tries to do a serial write at the same time.
- * Since the lock will only come under contention when the system is
- * swapping and available memory is low, it makes sense to share one
- * buffer across all the serial ports, since it significantly saves
- * memory if large numbers of serial ports are open.
- */
- static unsigned char tmp_buf[4096]; /* This is cheating */
- static 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 %sn";
- static const char *badinfo = KERN_WARNING
- "Warning: null sgi_serial for (%d, %d) in %sn";
- 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;
- if (ioc_icontrol)
- junk = ioc_icontrol->istat0;
- udelay(1);
- retval = channel->control;
- return retval;
- }
- static inline void write_zsreg(struct sgi_zschannel *channel,
- unsigned char reg, unsigned char value)
- {
- volatile unsigned char junk;
- udelay(2);
- channel->control = reg;
- if (ioc_icontrol)
- junk = ioc_icontrol->istat0;
- udelay(1);
- channel->control = value;
- if (ioc_icontrol)
- junk = ioc_icontrol->istat0;
- return;
- }
- static inline void load_zsregs(struct sgi_zschannel *channel, unsigned char *regs)
- {
- ZS_CLEARERR(channel);
- ZS_CLEARFIFO(channel);
- /* Load 'em up */
- write_zsreg(channel, R4, regs[R4]);
- write_zsreg(channel, R10, regs[R10]);
- write_zsreg(channel, R3, regs[R3] & ~RxENABLE);
- write_zsreg(channel, R5, regs[R5] & ~TxENAB);
- write_zsreg(channel, R1, regs[R1]);
- write_zsreg(channel, R9, regs[R9]);
- write_zsreg(channel, R11, regs[R11]);
- write_zsreg(channel, R12, regs[R12]);
- write_zsreg(channel, R13, regs[R13]);
- write_zsreg(channel, R14, regs[R14]);
- write_zsreg(channel, R15, regs[R15]);
- write_zsreg(channel, R3, regs[R3]);
- write_zsreg(channel, R5, regs[R5]);
- return;
- }
- /* Sets or clears DTR/RTS on the requested line */
- static inline void zs_rtsdtr(struct sgi_serial *ss, int set)
- {
- if(set) {
- ss->curregs[5] |= (RTS | DTR);
- ss->pendregs[5] = ss->curregs[5];
- write_zsreg(ss->zs_channel, 5, ss->curregs[5]);
- } else {
- ss->curregs[5] &= ~(RTS | DTR);
- ss->pendregs[5] = ss->curregs[5];
- write_zsreg(ss->zs_channel, 5, ss->curregs[5]);
- }
- return;
- }
- static inline void kgdb_chaninit(struct sgi_serial *ss, int intson, int bps)
- {
- int brg;
- if(intson) {
- kgdb_regs[R1] = INT_ALL_Rx;
- kgdb_regs[R9] |= MIE;
- } else {
- kgdb_regs[R1] = 0;
- kgdb_regs[R9] &= ~MIE;
- }
- brg = BPS_TO_BRG(bps, ZS_CLOCK/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;
- info->pendregs[5] &= ~TxENAB;
- write_zsreg(info->zs_channel, 5, info->curregs[5]);
- }
- restore_flags(flags);
- }
- static void rs_start(struct tty_struct *tty)
- {
- struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
- unsigned long flags;
-
- if (serial_paranoia_check(info, tty->device, "rs_start"))
- return;
-
- save_flags(flags); cli();
- if (info->xmit_cnt && info->xmit_buf && !(info->curregs[5] & TxENAB)) {
- info->curregs[5] |= TxENAB;
- info->pendregs[5] = info->curregs[5];
- write_zsreg(info->zs_channel, 5, info->curregs[5]);
- }
- restore_flags(flags);
- }
- /* Drop into either the boot monitor or kadb upon receiving a break
- * from keyboard/console input.
- */
- static void batten_down_hatches(void)
- {
- 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 = ioc_icontrol->istat0;
- udelay(2);
- zsc->control = RES_H_IUS;
- junk = ioc_icontrol->istat0;
- }
- /*
- * ----------------------------------------------------------------------
- *
- * Here starts the interrupt handling routines. All of the following
- * subroutines are declared as inline and are folded into
- * rs_interrupt(). They were separated out for readability's sake.
- *
- * Note: rs_interrupt() is a "fast" interrupt, which means that it
- * runs with interrupts turned off. People who may want to modify
- * rs_interrupt() should try to keep the interrupt handler as fast as
- * possible. After you are done making modifications, it is not a bad
- * idea to do:
- *
- * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
- *
- * and look at the resulting assemble code in serial.s.
- *
- * - Ted Ts'o (tytso@mit.edu), 7-Mar-93
- * -----------------------------------------------------------------------
- */
- /*
- * This routine is used by the interrupt handler to schedule
- * processing in the software interrupt portion of the driver.
- */
- static _INLINE_ void rs_sched_event(struct sgi_serial *info,
- int event)
- {
- info->event |= 1 << event;
- queue_task(&info->tqueue, &tq_serial);
- mark_bh(SERIAL_BH);
- }
- #ifdef CONFIG_REMOTE_DEBUG
- extern void set_async_breakpoint(unsigned int epc);
- #endif
- static _INLINE_ void receive_chars(struct sgi_serial *info, struct pt_regs *regs)
- {
- struct tty_struct *tty = info->tty;
- volatile unsigned char junk;
- unsigned char ch, stat;
- udelay(2);
- ch = info->zs_channel->data;
- junk = ioc_icontrol->istat0;
- udelay(2);
- stat = read_zsreg(info->zs_channel, R1);
- /* If this is the console keyboard, we need to handle
- * L1-A's here.
- */
- if(info->is_cons) {
- if(ch==0) { /* whee, break received */
- batten_down_hatches();
- rs_recv_clear(info->zs_channel);
- return;
- } else if (ch == 1) {
- show_state();
- return;
- } else if (ch == 2) {
- show_buffers();
- return;
- }
- /* It is a 'keyboard interrupt' ;-) */
- wake_up(&keypress_wait);
- }
- /* Look for kgdb 'stop' character, consult the gdb documentation
- * for remote target debugging and arch/sparc/kernel/sparc-stub.c
- * to see how all this works.
- */
- #ifdef CONFIG_REMOTE_DEBUG
- if((info->kgdb_channel) && (ch ==' 03')) {
- 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 = ioc_icontrol->istat0;
- info->x_char = 0;
- goto clear_and_return;
- }
- if((info->xmit_cnt <= 0) || info->tty->stopped) {
- /* That's peculiar... */
- udelay(2);
- info->zs_channel->control = RES_Tx_P;
- junk = ioc_icontrol->istat0;
- goto clear_and_return;
- }
- /* Send char */
- udelay(2);
- info->zs_channel->data = info->xmit_buf[info->xmit_tail++];
- junk = ioc_icontrol->istat0;
- info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
- info->xmit_cnt--;
- if (info->xmit_cnt < WAKEUP_CHARS)
- rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
- if(info->xmit_cnt <= 0) {
- udelay(2);
- info->zs_channel->control = RES_Tx_P;
- junk = ioc_icontrol->istat0;
- goto clear_and_return;
- }
- clear_and_return:
- /* Clear interrupt */
- udelay(2);
- info->zs_channel->control = RES_H_IUS;
- junk = ioc_icontrol->istat0;
- return;
- }
- static _INLINE_ void status_handle(struct sgi_serial *info)
- {
- volatile unsigned char junk;
- unsigned char status;
- /* Get status from Read Register 0 */
- udelay(2);
- status = info->zs_channel->control;
- junk = ioc_icontrol->istat0;
- /* Clear status condition... */
- udelay(2);
- info->zs_channel->control = RES_EXT_INT;
- junk = ioc_icontrol->istat0;
- /* Clear the interrupt */
- udelay(2);
- info->zs_channel->control = RES_H_IUS;
- junk = ioc_icontrol->istat0;
- #if 0
- if(status & DCD) {
- if((info->tty->termios->c_cflag & CRTSCTS) &&
- ((info->curregs[3] & AUTO_ENAB)==0)) {
- info->curregs[3] |= AUTO_ENAB;
- info->pendregs[3] |= AUTO_ENAB;
- write_zsreg(info->zs_channel, 3, info->curregs[3]);
- }
- } else {
- if((info->curregs[3] & AUTO_ENAB)) {
- info->curregs[3] &= ~AUTO_ENAB;
- info->pendregs[3] &= ~AUTO_ENAB;
- write_zsreg(info->zs_channel, 3, info->curregs[3]);
- }
- }
- #endif
- /* Whee, if this is console input and this is a
- * 'break asserted' status change interrupt, call
- * the boot prom.
- */
- if((status & BRK_ABRT) && info->break_abort)
- batten_down_hatches();
- /* XXX Whee, put in a buffer somewhere, the status information
- * XXX whee whee whee... Where does the information go...
- */
- return;
- }
- /*
- * This is the serial driver's generic interrupt routine
- */
- void rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
- {
- struct sgi_serial * info = (struct sgi_serial *) dev_id;
- unsigned char zs_intreg;
- zs_intreg = read_zsreg(info->zs_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 = ioc_icontrol->istat0;
- udelay(2);
- info->zs_channel->control = RES_H_IUS;
- junk = ioc_icontrol->istat0;
- /*
- * Now, initialize the Zilog
- */
- zs_rtsdtr(info, 1);
- /*
- * Finally, enable sequencing and interrupts
- */
- info->curregs[1] |= (info->curregs[1] & ~0x18) | (EXT_INT_ENAB|INT_ALL_Rx);
- info->pendregs[1] = info->curregs[1];
- info->curregs[3] |= (RxENABLE | Rx8);
- info->pendregs[3] = info->curregs[3];
- /* We enable Tx interrupts as needed. */
- info->curregs[5] |= (TxENAB | Tx8);
- info->pendregs[5] = info->curregs[5];
- info->curregs[9] |= (NV | MIE);
- info->pendregs[9] = info->curregs[9];
- write_zsreg(info->zs_channel, 3, info->curregs[3]);
- write_zsreg(info->zs_channel, 5, info->curregs[5]);
- write_zsreg(info->zs_channel, 9, info->curregs[9]);
-
- /*
- * And clear the interrupt registers again for luck.
- */
- udelay(2);
- info->zs_channel->control = ERR_RES;
- junk = ioc_icontrol->istat0;
- udelay(2);
- info->zs_channel->control = RES_H_IUS;
- junk = ioc_icontrol->istat0;
- if (info->tty)
- clear_bit(TTY_IO_ERROR, &info->tty->flags);
- info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
- /*
- * and set the speed of the serial port
- */
- change_speed(info);
- info->flags |= ZILOG_INITIALIZED;
- restore_flags(flags);
- return 0;
- }
- /*
- * This routine will shutdown a serial port; interrupts are disabled, and
- * DTR is dropped if the hangup on close termio flag is on.
- */
- static void shutdown(struct sgi_serial * info)
- {
- unsigned long flags;
- if (!(info->flags & ZILOG_INITIALIZED))
- return;
- #ifdef SERIAL_DEBUG_OPEN
- printk("Shutting down serial port %d (irq %d)....", info->line,
- info->irq);
- #endif
-
- save_flags(flags); cli(); /* Disable interrupts */
-
- if (info->xmit_buf) {
- free_page((unsigned long) info->xmit_buf);
- info->xmit_buf = 0;
- }
- if (info->tty)
- set_bit(TTY_IO_ERROR, &info->tty->flags);
-
- info->flags &= ~ZILOG_INITIALIZED;
- restore_flags(flags);
- }
- /*
- * This routine is called to set the UART divisor registers to match
- * the specified baud rate for a serial port.
- */
- static void change_speed(struct sgi_serial *info)
- {
- unsigned short port;
- unsigned cflag;
- int i;
- int brg;
- if (!info->tty || !info->tty->termios)
- return;
- cflag = info->tty->termios->c_cflag;
- if (!(port = info->port))
- return;
- i = cflag & CBAUD;
- if (i & CBAUDEX) {
- /* XXX CBAUDEX is not obeyed.
- * It is impossible at a 32bits SPARC.
- * But we have to report this to user ... someday.
- */
- i = B9600;
- }
- if (i == 0) {
- /* XXX B0, hangup the line. */
- do_serial_hangup(info);
- } else if (baud_table[i]) {
- info->zs_baud = baud_table[i];
- info->clk_divisor = 16;
- info->curregs[4] = X16CLK;
- info->curregs[11] = TCBR | RCBR;
- brg = BPS_TO_BRG(info->zs_baud, ZS_CLOCK/info->clk_divisor);
- info->curregs[12] = (brg & 255);
- info->curregs[13] = ((brg >> 8) & 255);
- info->curregs[14] = BRENABL;
- }
- /* byte size and parity */
- switch (cflag & CSIZE) {
- case CS5:
- info->curregs[3] &= ~(0xc0);
- info->curregs[3] |= Rx5;
- info->pendregs[3] = info->curregs[3];
- info->curregs[5] &= ~(0xe0);
- info->curregs[5] |= Tx5;
- info->pendregs[5] = info->curregs[5];
- break;
- case CS6:
- info->curregs[3] &= ~(0xc0);
- info->curregs[3] |= Rx6;
- info->pendregs[3] = info->curregs[3];
- info->curregs[5] &= ~(0xe0);
- info->curregs[5] |= Tx6;
- info->pendregs[5] = info->curregs[5];
- break;
- case CS7:
- info->curregs[3] &= ~(0xc0);
- info->curregs[3] |= Rx7;
- info->pendregs[3] = info->curregs[3];
- info->curregs[5] &= ~(0xe0);
- info->curregs[5] |= Tx7;
- info->pendregs[5] = info->curregs[5];
- break;
- case CS8:
- default: /* defaults to 8 bits */
- info->curregs[3] &= ~(0xc0);
- info->curregs[3] |= Rx8;
- info->pendregs[3] = info->curregs[3];
- info->curregs[5] &= ~(0xe0);
- info->curregs[5] |= Tx8;
- info->pendregs[5] = info->curregs[5];
- break;
- }
- info->curregs[4] &= ~(0x0c);
- if (cflag & CSTOPB) {
- info->curregs[4] |= SB2;
- } else {
- info->curregs[4] |= SB1;
- }
- info->pendregs[4] = info->curregs[4];
- if (cflag & PARENB) {
- info->curregs[4] |= PAR_ENA;
- info->pendregs[4] |= PAR_ENA;
- } else {
- info->curregs[4] &= ~PAR_ENA;
- info->pendregs[4] &= ~PAR_ENA;
- }
- if (!(cflag & PARODD)) {
- info->curregs[4] |= PAR_EVEN;
- info->pendregs[4] |= PAR_EVEN;
- } else {
- info->curregs[4] &= ~PAR_EVEN;
- info->pendregs[4] &= ~PAR_EVEN;
- }
- /* Load up the new values */
- load_zsregs(info->zs_channel, info->curregs);
- return;
- }
- /* This is for console output over ttya/ttyb */
- static void zs_cons_put_char(char ch)
- {
- struct sgi_zschannel *chan = zs_conschan;
- volatile unsigned char junk;
- int flags, loops = 0;
- save_flags(flags); cli();
- while(((junk = chan->control) & Tx_BUF_EMP)==0 && loops < 10000) {
- loops++;
- udelay(2);
- }
- udelay(2);
- chan->data = ch;
- junk = ioc_icontrol->istat0;
- restore_flags(flags);
- }
- /*
- * 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;
- int flags, loops = 0;
- save_flags(flags); cli();
- while(((junk = chan->control) & Tx_BUF_EMP)==0 && loops < 10000) {
- loops++;
- udelay(2);
- }
- udelay(2);
- chan->data = ch;
- junk = ioc_icontrol->istat0;
- restore_flags(flags);
- }
- /* These are for receiving and sending characters under the kgdb
- * source level kernel debugger.
- */
- 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 = ioc_icontrol->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 = ioc_icontrol->istat0;
- udelay(2);
- return chan->data;
- }
- /*
- * Fair output driver allows a process to speak.
- */
- static void rs_fair_output(void)
- {
- int left; /* Output no more than that */
- unsigned long flags;
- struct sgi_serial *info = zs_consinfo;
- volatile unsigned char junk;
- char c;
- if (info == 0) return;
- if (info->xmit_buf == 0) return;
- save_flags(flags); cli();
- left = info->xmit_cnt;
- while (left != 0) {
- c = info->xmit_buf[info->xmit_tail];
- info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1);
- info->xmit_cnt--;
- restore_flags(flags);
- 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 = ioc_icontrol->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;
- info->pendregs[1] |= TxINT_ENAB|EXT_INT_ENAB;
- write_zsreg(info->zs_channel, 1, info->curregs[1]);
- info->curregs[5] |= TxENAB;
- info->pendregs[5] |= TxENAB;
- write_zsreg(info->zs_channel, 5, info->curregs[5]);
- /*
- * 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;
- info->pendregs[1] |= TxINT_ENAB|EXT_INT_ENAB;
- write_zsreg(info->zs_channel, 1, info->curregs[1]);
- info->curregs[5] |= TxENAB;
- info->pendregs[5] |= TxENAB;
- write_zsreg(info->zs_channel, 5, info->curregs[5]);
- /*
- * Send a first (bootstrapping) character. A best solution is
- * to call transmit_chars() here which handles output in a
- * generic way. Current transmit_chars() not only transmits,
- * but resets interrupts also what we do not desire here.
- * XXX Discuss with David.
- */
- if (info->zs_channel->control & Tx_BUF_EMP) {
- volatile unsigned char junk;
- /* Send char */
- udelay(2);
- info->zs_channel->data = info->xmit_buf[info->xmit_tail++];
- junk = ioc_icontrol->istat0;
- info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
- info->xmit_cnt--;
- }
- restore_flags(flags);
- }
- /*
- * ------------------------------------------------------------
- * rs_throttle()
- *
- * This routine is called by the upper-layer tty layer to signal that
- * incoming characters should be throttled.
- * ------------------------------------------------------------
- */
- static void rs_throttle(struct tty_struct * tty)
- {
- struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
- #ifdef SERIAL_DEBUG_THROTTLE
- char buf[64];
-
- printk("throttle %s: %d....n", _tty_name(tty, buf),
- tty->ldisc.chars_in_buffer(tty));
- #endif
- if (serial_paranoia_check(info, tty->device, "rs_throttle"))
- return;
-
- if (I_IXOFF(tty))
- info->x_char = STOP_CHAR(tty);
- /* Turn off RTS line */
- cli();
- info->curregs[5] &= ~RTS;
- info->pendregs[5] &= ~RTS;
- write_zsreg(info->zs_channel, 5, info->curregs[5]);
- sti();
- }
- static void rs_unthrottle(struct tty_struct * tty)
- {
- struct sgi_serial *info = (struct sgi_serial *)tty->driver_data;
- #ifdef SERIAL_DEBUG_THROTTLE
- char buf[64];
-
- printk("unthrottle %s: %d....n", _tty_name(tty, buf),
- tty->ldisc.chars_in_buffer(tty));
- #endif
- if (serial_paranoia_check(info, tty->device, "rs_unthrottle"))
- return;
-
- if (I_IXOFF(tty)) {
- if (info->x_char)
- info->x_char = 0;
- else
- info->x_char = START_CHAR(tty);
- }
- /* Assert RTS line */
- cli();
- info->curregs[5] |= RTS;
- info->pendregs[5] |= RTS;
- write_zsreg(info->zs_channel, 5, info->curregs[5]);
- sti();
- }
- /*
- * ------------------------------------------------------------
- * rs_ioctl() and friends
- * ------------------------------------------------------------
- */
- static int get_serial_info(struct sgi_serial * info,
- struct serial_struct * retinfo)
- {
- struct serial_struct tmp;
-
- if (!retinfo)
- return -EFAULT;
- memset(&tmp, 0, sizeof(tmp));
- tmp.type = info->type;
- tmp.line = info->line;
- tmp.port = info->port;
- tmp.irq = info->irq;
- tmp.flags = info->flags;
- tmp.baud_base = info->baud_base;
- tmp.close_delay = info->close_delay;
- tmp.closing_wait = info->closing_wait;
- tmp.custom_divisor = info->custom_divisor;
- return copy_to_user(retinfo,&tmp,sizeof(*retinfo));
- }
- static int set_serial_info(struct sgi_serial * info,
- struct serial_struct * new_info)
- {
- struct serial_struct new_serial;
- struct sgi_serial old_info;
- int retval = 0;
- if (!new_info)
- return -EFAULT;
- copy_from_user(&new_serial,new_info,sizeof(new_serial));
- old_info = *info;
- if (!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 = ioc_icontrol->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 = %dn", 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 %dn", info->count);
- info->count = 1;
- }
- if (--info->count < 0) {
- printk("rs_close: bad serial port count for ttys%d: %dn",
- info->line, info->count);
- info->count = 0;
- }
- if (info->count) {
- restore_flags(flags);
- return;
- }
- info->flags |= ZILOG_CLOSING;
- /*
- * Save the termios structure, since this port may have
- * separate termios for callout and dialin.
- */
- if (info->flags & ZILOG_NORMAL_ACTIVE)
- info->normal_termios = *tty->termios;
- if (info->flags & ZILOG_CALLOUT_ACTIVE)
- info->callout_termios = *tty->termios;
- /*
- * Now we wait for the transmit buffer to clear; and we notify
- * the line discipline to only process XON/XOFF characters.
- */
- tty->closing = 1;
- if (info->closing_wait != ZILOG_CLOSING_WAIT_NONE)
- tty_wait_until_sent(tty, info->closing_wait);
- /*
- * At this point we stop accepting input. To do this, we
- * disable the receive line status interrupts, and tell the
- * interrupt driver to stop checking the data ready bit in the
- * line status register.
- */
- /** if (!info->iscons) ... **/
- info->curregs[3] &= ~RxENABLE;
- info->pendregs[3] = info->curregs[3];
- write_zsreg(info->zs_channel, 3, info->curregs[3]);
- info->curregs[1] &= ~(0x18);
- info->pendregs[1] = info->curregs[1];
- write_zsreg(info->zs_channel, 1, info->curregs[1]);
- ZS_CLEARFIFO(info->zs_channel);
- shutdown(info);
- if (tty->driver.flush_buffer)
- tty->driver.flush_buffer(tty);
- if (tty->ldisc.flush_buffer)
- tty->ldisc.flush_buffer(tty);
- tty->closing = 0;
- info->event = 0;
- info->tty = 0;
- if (tty->ldisc.num != ldiscs[N_TTY].num) {
- if (tty->ldisc.close)
- (tty->ldisc.close)(tty);
- tty->ldisc = ldiscs[N_TTY];
- tty->termios->c_line = N_TTY;
- if (tty->ldisc.open)
- (tty->ldisc.open)(tty);
- }
- if (info->blocked_open) {
- if (info->close_delay) {
- current->state = TASK_INTERRUPTIBLE;
- 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 = %dn",
- 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 = %dn",
- 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 = %dn",
- 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 = %dn", 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 %dn",
- 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 1.00n");
- }
- /* Return layout for the requested zs chip number. */
- static inline struct sgi_zslayout *get_zs(int chip)
- {
- extern struct hpc3_miscregs *hpc3mregs;
- if (chip > 0)
- panic("Wheee, bogus zs chip number requested.");
- return (struct sgi_zslayout *) (&hpc3mregs->ser1cmd);
- }
- 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/On", ((channel>>1)&1));
- msg_printed = 1;
- }
- } else {
- printk("zs%d: console %sn", ((channel>>1)&1),
- (i==1 ? "input" : (o==1 ? "output" : "WEIRD")));
- }
- }
- volatile int test_done;
- /* rs_init inits the driver */
- int rs_init(void)
- {
- int chip, channel, i, flags;
- struct sgi_serial *info;
- /* Setup base handler, and timer table. */
- init_bh(SERIAL_BH, do_serial_bh);
- show_serial_version();
- /* Initialize the tty_driver structure */
- /* SGI: Not all of this is exactly right for us. */
-
- memset(&serial_driver, 0, sizeof(struct tty_driver));
- serial_driver.magic = TTY_DRIVER_MAGIC;
- serial_driver.name = "ttyS";
- serial_driver.major = TTY_MAJOR;
- serial_driver.minor_start = 64;
- serial_driver.num = NUM_CHANNELS;
- serial_driver.type = TTY_DRIVER_TYPE_SERIAL;
- serial_driver.subtype = SERIAL_TYPE_NORMAL;
- serial_driver.init_termios = tty_std_termios;
- serial_driver.init_termios.c_cflag =
- B9600 | CS8 | CREAD | HUPCL | CLOCAL;
- serial_driver.flags = TTY_DRIVER_REAL_RAW;
- serial_driver.refcount = &serial_refcount;
- serial_driver.table = serial_table;
- serial_driver.termios = serial_termios;
- serial_driver.termios_locked = serial_termios_locked;
- serial_driver.open = rs_open;
- serial_driver.close = rs_close;
- serial_driver.write = rs_write;
- serial_driver.flush_chars = rs_flush_chars;
- serial_driver.write_room = rs_write_room;
- serial_driver.chars_in_buffer = rs_chars_in_buffer;
- serial_driver.flush_buffer = rs_flush_buffer;
- serial_driver.ioctl = rs_ioctl;
- serial_driver.throttle = rs_throttle;
- serial_driver.unthrottle = rs_unthrottle;
- serial_driver.set_termios = rs_set_termios;
- serial_driver.stop = rs_stop;
- serial_driver.start = rs_start;
- serial_driver.hangup = rs_hangup;
- /*
- * The callout device is just like normal device except for
- * major number and the subtype code.
- */
- callout_driver = serial_driver;
- callout_driver.name = "cua";
- callout_driver.major = TTYAUX_MAJOR;
- callout_driver.subtype = SERIAL_TYPE_CALLOUT;
- if (tty_register_driver(&serial_driver))
- panic("Couldn't register serial drivern");
- if (tty_register_driver(&callout_driver))
- panic("Couldn't register callout drivern");
-
- 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 Zilog8530n");
- }
- if (request_irq(zilog_irq, rs_interrupt, (SA_INTERRUPT),
- "Zilog8530", zs_chain))
- panic("Unable to attach zs intrn");
- 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 int zs_console_wait_key(struct console *con)
- {
- sleep_on(&keypress_wait);
- return 0;
- }
- 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;
- int bits = 8;
- int parity = 'n';
- int cflag = CREAD | HUPCL | CLOCAL;
- char *s, *dbaud;
- 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';
- }
- else {
- /* If the user doesn't set console=... try to read the
- * PROM variable - if this fails use 9600 baud and
- * inform the user about the problem
- */
- dbaud = ArcGetEnvironmentVariable("dbaud");
- if(dbaud) baud = simple_strtoul(dbaud, NULL, 10);
- else {
- /* Use prom_printf() to make sure that the user
- * is getting anything ...
- */
- prom_printf("No dbaud set in PROM ?!? Using 9600.n");
- baud = 9600;
- }
- }
- /*
- * 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 baudn",
- 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));
- memcpy(info->pendregs, 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,
- wait_key: zs_console_wait_key,
- 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);