2 * dz.c: Serial port driver for DECStations equiped
5 * Copyright (C) 1998 Olivier A. D. Lebaillif
7 * Email: olivier.lebaillif@ifrsys.com
10 * Changed IRQ to use Harald's dec internals interrupts.h
11 * removed base_addr code - moving address assignment to setup.c
12 * Changed name of dz_init to rs_init to be consistent with tc code
13 * [13-NOV-98] triemer fixed code to receive characters
14 * after patches by harald to irq code.
15 * [09-JAN-99] triemer minor fix for schedule - due to removal of timeout
16 * field from "current" - somewhere between 2.1.121 and 2.1.131
17 Qua Jun 27 15:02:26 BRT 2001
18 * [27-JUN-2001] Arnaldo Carvalho de Melo <acme@conectiva.com.br> - cleanups
20 * Parts (C) 1999 David Airlie, airlied@linux.ie
21 * [07-SEP-99] Bugfixes
23 * [06-Jan-2002] Russell King <rmk@arm.linux.org.uk>
24 * Converted to new serial core
29 #include <linux/config.h>
30 #include <linux/module.h>
31 #include <linux/interrupt.h>
32 #include <linux/init.h>
33 #include <linux/console.h>
34 #include <linux/tty.h>
35 #include <linux/tty_flip.h>
36 #include <linux/serial_core.h>
37 #include <linux/serial.h>
39 #include <asm/bootinfo.h>
40 #include <asm/dec/interrupts.h>
41 #include <asm/dec/kn01.h>
42 #include <asm/dec/kn02.h>
43 #include <asm/dec/machtype.h>
44 #include <asm/dec/prom.h>
46 #include <asm/system.h>
47 #include <asm/uaccess.h>
49 #define CONSOLE_LINE (3) /* for definition of struct console */
53 #define DZ_INTR_DEBUG 1
55 static char *dz_name
= "DECstation DZ serial driver version ";
56 static char *dz_version
= "1.02";
59 struct uart_port port
;
63 static struct dz_port dz_ports
[DZ_NB_PORT
];
67 * debugging code to send out chars via prom
69 static void debug_console(const char *s
, int count
)
73 for (i
= 0; i
< count
; i
++) {
75 prom_printf("%c", 13);
76 prom_printf("%c", *s
++);
82 * ------------------------------------------------------------
83 * dz_in () and dz_out ()
85 * These routines are used to access the registers of the DZ
86 * chip, hiding relocation differences between implementation.
87 * ------------------------------------------------------------
90 static inline unsigned short dz_in(struct dz_port
*dport
, unsigned offset
)
92 volatile unsigned short *addr
=
93 (volatile unsigned short *) (dport
->port
.membase
+ offset
);
97 static inline void dz_out(struct dz_port
*dport
, unsigned offset
,
100 volatile unsigned short *addr
=
101 (volatile unsigned short *) (dport
->port
.membase
+ offset
);
106 * ------------------------------------------------------------
107 * rs_stop () and rs_start ()
109 * These routines are called before setting or resetting
110 * tty->stopped. They enable or disable transmitter interrupts,
112 * ------------------------------------------------------------
115 static void dz_stop_tx(struct uart_port
*uport
, unsigned int tty_stop
)
117 struct dz_port
*dport
= (struct dz_port
*)uport
;
118 unsigned short tmp
, mask
= 1 << dport
->port
.line
;
121 spin_lock_irqsave(&dport
->port
.lock
, flags
);
122 tmp
= dz_in(dport
, DZ_TCR
); /* read the TX flag */
123 tmp
&= ~mask
; /* clear the TX flag */
124 dz_out(dport
, DZ_TCR
, tmp
);
125 spin_unlock_irqrestore(&dport
->port
.lock
, flags
);
128 static void dz_start_tx(struct uart_port
*uport
, unsigned int tty_start
)
130 struct dz_port
*dport
= (struct dz_port
*)uport
;
131 unsigned short tmp
, mask
= 1 << dport
->port
.line
;
134 spin_lock_irqsave(&dport
->port
.lock
, flags
);
135 tmp
= dz_in(dport
, DZ_TCR
); /* read the TX flag */
136 tmp
|= mask
; /* set the TX flag */
137 dz_out(dport
, DZ_TCR
, tmp
);
138 spin_unlock_irqrestore(&dport
->port
.lock
, flags
);
141 static void dz_stop_rx(struct uart_port
*uport
)
143 struct dz_port
*dport
= (struct dz_port
*)uport
;
146 spin_lock_irqsave(&dport
->port
.lock
, flags
);
147 dport
->cflag
&= ~DZ_CREAD
;
148 dz_out(dport
, DZ_LPR
, dport
->cflag
);
149 spin_unlock_irqrestore(&dport
->port
.lock
, flags
);
152 static void dz_enable_ms(struct uart_port
*port
)
158 * ------------------------------------------------------------
159 * Here starts the interrupt handling routines. All of the
160 * following subroutines are declared as inline and are folded
161 * into dz_interrupt. They were separated out for readability's
164 * Note: rs_interrupt() is a "fast" interrupt, which means that it
165 * runs with interrupts turned off. People who may want to modify
166 * rs_interrupt() should try to keep the interrupt handler as fast as
167 * possible. After you are done making modifications, it is not a bad
170 * make drivers/serial/dz.s
172 * and look at the resulting assemble code in dz.s.
174 * ------------------------------------------------------------
178 * ------------------------------------------------------------
181 * This routine deals with inputs from any lines.
182 * ------------------------------------------------------------
184 static inline void dz_receive_chars(struct dz_port
*dport
)
186 struct tty_struct
*tty
= NULL
;
187 struct uart_icount
*icount
;
189 unsigned short status
, tmp
;
190 unsigned char ch
, flag
;
192 /* this code is going to be a problem...
193 the call to tty_flip_buffer is going to need
197 status
= dz_in(dport
, DZ_RBUF
);
199 /* punt so we don't get duplicate characters */
200 if (!(status
& DZ_DVAL
))
204 ch
= UCHAR(status
); /* grab the char */
208 if (info
->is_console
) {
210 return; /* it's a break ... */
214 tty
= dport
->port
.info
->tty
;/* now tty points to the proper dev */
215 icount
= &dport
->port
.icount
;
219 if (tty
->flip
.count
>= TTY_FLIPBUF_SIZE
)
224 /* keep track of the statistics */
225 if (status
& (DZ_OERR
| DZ_FERR
| DZ_PERR
)) {
226 if (status
& DZ_PERR
) /* parity error */
228 else if (status
& DZ_FERR
) /* frame error */
230 if (status
& DZ_OERR
) /* overrun error */
233 /* check to see if we should ignore the character
234 and mask off conditions that should be ignored
237 if (status
& dport
->port
.ignore_status_mask
) {
242 /* mask off the error conditions we want to ignore */
243 tmp
= status
& dport
->port
.read_status_mask
;
248 debug_console("PERR\n", 5);
250 } else if (tmp
& DZ_FERR
) {
253 debug_console("FERR\n", 5);
258 debug_console("OERR\n", 5);
260 tty_insert_flip_char(tty
, ch
, flag
);
265 tty_insert_flip_char(tty
, ch
, flag
);
267 } while (status
& DZ_DVAL
);
270 tty_flip_buffer_push(tty
);
274 * ------------------------------------------------------------
277 * This routine deals with outputs to any lines.
278 * ------------------------------------------------------------
280 static inline void dz_transmit_chars(struct dz_port
*dport
)
282 struct circ_buf
*xmit
= &dport
->port
.info
->xmit
;
285 if (dport
->port
.x_char
) { /* XON/XOFF chars */
286 dz_out(dport
, DZ_TDR
, dport
->port
.x_char
);
287 dport
->port
.icount
.tx
++;
288 dport
->port
.x_char
= 0;
291 /* if nothing to do or stopped or hardware stopped */
292 if (uart_circ_empty(xmit
) || uart_tx_stopped(&dport
->port
)) {
293 dz_stop_tx(&dport
->port
, 0);
298 * if something to do ... (rember the dz has no output fifo so we go
299 * one char at a time :-<
301 tmp
= xmit
->buf
[xmit
->tail
];
302 xmit
->tail
= (xmit
->tail
+ 1) & (DZ_XMIT_SIZE
- 1);
303 dz_out(dport
, DZ_TDR
, tmp
);
304 dport
->port
.icount
.tx
++;
306 if (uart_circ_chars_pending(xmit
) < DZ_WAKEUP_CHARS
)
307 uart_write_wakeup(&dport
->port
);
310 if (uart_circ_empty(xmit
))
311 dz_stop_tx(&dport
->port
, 0);
315 * ------------------------------------------------------------
316 * check_modem_status ()
318 * Only valid for the MODEM line duh !
319 * ------------------------------------------------------------
321 static inline void check_modem_status(struct dz_port
*dport
)
323 unsigned short status
;
325 /* if not ne modem line just return */
326 if (dport
->port
.line
!= DZ_MODEM
)
329 status
= dz_in(dport
, DZ_MSR
);
331 /* it's easy, since DSR2 is the only bit in the register */
333 dport
->port
.icount
.dsr
++;
337 * ------------------------------------------------------------
340 * this is the main interrupt routine for the DZ chip.
341 * It deals with the multiple ports.
342 * ------------------------------------------------------------
344 static irqreturn_t
dz_interrupt(int irq
, void *dev
, struct pt_regs
*regs
)
346 struct dz_port
*dport
;
347 unsigned short status
;
349 /* get the reason why we just got an irq */
350 status
= dz_in((struct dz_port
*)dev
, DZ_CSR
);
351 dport
= &dz_ports
[LINE(status
)];
353 if (status
& DZ_RDONE
)
354 dz_receive_chars(dport
);
356 if (status
& DZ_TRDY
)
357 dz_transmit_chars(dport
);
359 /* FIXME: what about check modem status??? --rmk */
365 * -------------------------------------------------------------------
366 * Here ends the DZ interrupt routines.
367 * -------------------------------------------------------------------
370 static unsigned int dz_get_mctrl(struct uart_port
*uport
)
372 struct dz_port
*dport
= (struct dz_port
*)uport
;
373 unsigned int mctrl
= TIOCM_CAR
| TIOCM_DSR
| TIOCM_CTS
;
375 if (dport
->port
.line
== DZ_MODEM
) {
377 * CHECKME: This is a guess from the other code... --rmk
379 if (dz_in(dport
, DZ_MSR
) & DZ_MODEM_DSR
)
386 static void dz_set_mctrl(struct uart_port
*uport
, unsigned int mctrl
)
388 struct dz_port
*dport
= (struct dz_port
*)uport
;
391 if (dport
->port
.line
== DZ_MODEM
) {
392 tmp
= dz_in(dport
, DZ_TCR
);
393 if (mctrl
& TIOCM_DTR
)
394 tmp
&= ~DZ_MODEM_DTR
;
397 dz_out(dport
, DZ_TCR
, tmp
);
402 * -------------------------------------------------------------------
405 * various initialization tasks
406 * -------------------------------------------------------------------
408 static int dz_startup(struct uart_port
*uport
)
410 struct dz_port
*dport
= (struct dz_port
*)uport
;
414 /* The dz lines for the mouse/keyboard must be
415 * opened using their respective drivers.
417 if ((dport
->port
.line
== DZ_KEYBOARD
) ||
418 (dport
->port
.line
== DZ_MOUSE
))
421 spin_lock_irqsave(&dport
->port
.lock
, flags
);
423 /* enable the interrupt and the scanning */
424 tmp
= dz_in(dport
, DZ_CSR
);
425 tmp
|= DZ_RIE
| DZ_TIE
| DZ_MSE
;
426 dz_out(dport
, DZ_CSR
, tmp
);
428 spin_unlock_irqrestore(&dport
->port
.lock
, flags
);
434 * -------------------------------------------------------------------
437 * This routine will shutdown a serial port; interrupts are disabled, and
438 * DTR is dropped if the hangup on close termio flag is on.
439 * -------------------------------------------------------------------
441 static void dz_shutdown(struct uart_port
*uport
)
443 dz_stop_tx(uport
, 0);
447 * get_lsr_info - get line status register info
449 * Purpose: Let user call ioctl() to get info when the UART physically
450 * is emptied. On bus types like RS485, the transmitter must
451 * release the bus after transmitting. This must be done when
452 * the transmit shift register is empty, not be done when the
453 * transmit holding register is empty. This functionality
454 * allows an RS485 driver to be written in user space.
456 static unsigned int dz_tx_empty(struct uart_port
*uport
)
458 struct dz_port
*dport
= (struct dz_port
*)uport
;
459 unsigned short status
= dz_in(dport
, DZ_LPR
);
461 /* FIXME: this appears to be obviously broken --rmk. */
462 return status
? TIOCSER_TEMT
: 0;
465 static void dz_break_ctl(struct uart_port
*uport
, int break_state
)
467 struct dz_port
*dport
= (struct dz_port
*)uport
;
469 unsigned short tmp
, mask
= 1 << uport
->line
;
471 spin_lock_irqsave(&uport
->lock
, flags
);
472 tmp
= dz_in(dport
, DZ_TCR
);
477 dz_out(dport
, DZ_TCR
, tmp
);
478 spin_unlock_irqrestore(&uport
->lock
, flags
);
481 static void dz_set_termios(struct uart_port
*uport
, struct termios
*termios
,
482 struct termios
*old_termios
)
484 struct dz_port
*dport
= (struct dz_port
*)uport
;
486 unsigned int cflag
, baud
;
488 cflag
= dport
->port
.line
;
490 switch (termios
->c_cflag
& CSIZE
) {
505 if (termios
->c_cflag
& CSTOPB
)
507 if (termios
->c_cflag
& PARENB
)
509 if (termios
->c_cflag
& PARODD
)
512 baud
= uart_get_baud_rate(uport
, termios
, old_termios
, 50, 9600);
561 if (termios
->c_cflag
& CREAD
)
564 spin_lock_irqsave(&dport
->port
.lock
, flags
);
566 dz_out(dport
, DZ_LPR
, cflag
);
567 dport
->cflag
= cflag
;
569 /* setup accept flag */
570 dport
->port
.read_status_mask
= DZ_OERR
;
571 if (termios
->c_iflag
& INPCK
)
572 dport
->port
.read_status_mask
|= DZ_FERR
| DZ_PERR
;
574 /* characters to ignore */
575 uport
->ignore_status_mask
= 0;
576 if (termios
->c_iflag
& IGNPAR
)
577 dport
->port
.ignore_status_mask
|= DZ_FERR
| DZ_PERR
;
579 spin_unlock_irqrestore(&dport
->port
.lock
, flags
);
582 static const char *dz_type(struct uart_port
*port
)
587 static void dz_release_port(struct uart_port
*port
)
592 static int dz_request_port(struct uart_port
*port
)
597 static void dz_config_port(struct uart_port
*port
, int flags
)
599 if (flags
& UART_CONFIG_TYPE
)
600 port
->type
= PORT_DZ
;
604 * verify the new serial_struct (for TIOCSSERIAL).
606 static int dz_verify_port(struct uart_port
*port
, struct serial_struct
*ser
)
609 if (ser
->type
!= PORT_UNKNOWN
&& ser
->type
!= PORT_DZ
)
611 if (ser
->irq
!= port
->irq
)
616 static struct uart_ops dz_ops
= {
617 .tx_empty
= dz_tx_empty
,
618 .get_mctrl
= dz_get_mctrl
,
619 .set_mctrl
= dz_set_mctrl
,
620 .stop_tx
= dz_stop_tx
,
621 .start_tx
= dz_start_tx
,
622 .stop_rx
= dz_stop_rx
,
623 .enable_ms
= dz_enable_ms
,
624 .break_ctl
= dz_break_ctl
,
625 .startup
= dz_startup
,
626 .shutdown
= dz_shutdown
,
627 .set_termios
= dz_set_termios
,
629 .release_port
= dz_release_port
,
630 .request_port
= dz_request_port
,
631 .config_port
= dz_config_port
,
632 .verify_port
= dz_verify_port
,
635 static void __init
dz_init_ports(void)
637 static int first
= 1;
638 struct dz_port
*dport
;
646 if (mips_machtype
== MACH_DS23100
||
647 mips_machtype
== MACH_DS5100
)
648 base
= (unsigned long) KN01_DZ11_BASE
;
650 base
= (unsigned long) KN02_DZ11_BASE
;
652 for (i
= 0, dport
= dz_ports
; i
< DZ_NB_PORT
; i
++, dport
++) {
653 spin_lock_init(&dport
->port
.lock
);
654 dport
->port
.membase
= (char *) base
;
655 dport
->port
.iotype
= SERIAL_IO_PORT
;
656 dport
->port
.irq
= dec_interrupt
[DEC_IRQ_DZ11
];
657 dport
->port
.line
= i
;
658 dport
->port
.fifosize
= 1;
659 dport
->port
.ops
= &dz_ops
;
660 dport
->port
.flags
= UPF_BOOT_AUTOCONF
;
664 static void dz_reset(struct dz_port
*dport
)
666 dz_out(dport
, DZ_CSR
, DZ_CLR
);
668 while (dz_in(dport
, DZ_CSR
) & DZ_CLR
);
669 /* FIXME: cpu_relax? */
673 /* enable scanning */
674 dz_out(dport
, DZ_CSR
, DZ_MSE
);
677 #ifdef CONFIG_SERIAL_DZ_CONSOLE
678 static void dz_console_put_char(struct dz_port
*dport
, unsigned char ch
)
682 unsigned short tmp
= ch
;
683 /* this code sends stuff out to serial device - spinning its
684 wheels and waiting. */
686 spin_lock_irqsave(&dport
->port
.lock
, flags
);
688 /* spin our wheels */
689 while (((dz_in(dport
, DZ_CSR
) & DZ_TRDY
) != DZ_TRDY
) && loops
--)
690 /* FIXME: cpu_relax, udelay? --rmk */
693 /* Actually transmit the character. */
694 dz_out(dport
, DZ_TDR
, tmp
);
696 spin_unlock_irqrestore(&dport
->port
.lock
, flags
);
699 * -------------------------------------------------------------------
700 * dz_console_print ()
702 * dz_console_print is registered for printk.
703 * The console must be locked when we get here.
704 * -------------------------------------------------------------------
706 static void dz_console_print(struct console
*cons
,
710 struct dz_port
*dport
= &dz_ports
[CONSOLE_LINE
];
712 prom_printf((char *) str
);
716 dz_console_put_char(dport
, '\r');
717 dz_console_put_char(dport
, *str
++);
721 static int __init
dz_console_setup(struct console
*co
, char *options
)
723 struct dz_port
*dport
= &dz_ports
[CONSOLE_LINE
];
729 unsigned short mask
, tmp
;
732 uart_parse_options(options
, &baud
, &parity
, &bits
, &flow
);
736 ret
= uart_set_options(&dport
->port
, co
, baud
, parity
, bits
, flow
);
738 mask
= 1 << dport
->port
.line
;
739 tmp
= dz_in(dport
, DZ_TCR
); /* read the TX flag */
741 tmp
|= mask
; /* set the TX flag */
742 dz_out(dport
, DZ_TCR
, tmp
);
749 static struct console dz_sercons
=
752 .write
= dz_console_print
,
753 .device
= uart_console_device
,
754 .setup
= dz_console_setup
,
755 .flags
= CON_CONSDEV
| CON_PRINTBUFFER
,
756 .index
= CONSOLE_LINE
,
759 void __init
dz_serial_console_init(void)
763 register_console(&dz_sercons
);
766 #define SERIAL_DZ_CONSOLE &dz_sercons
768 #define SERIAL_DZ_CONSOLE NULL
769 #endif /* CONFIG_SERIAL_DZ_CONSOLE */
771 static struct uart_driver dz_reg
= {
772 .owner
= THIS_MODULE
,
773 .driver_name
= "serial",
775 .dev_name
= "tts/%d",
777 .dev_name
= "ttyS%d",
782 .cons
= SERIAL_DZ_CONSOLE
,
785 int __init
dz_init(void)
790 printk("%s%s\n", dz_name
, dz_version
);
797 #ifndef CONFIG_SERIAL_DZ_CONSOLE
799 dz_reset(&dz_ports
[0]);
802 /* order matters here... the trick is that flags
803 is updated... in request_irq - to immediatedly obliterate
805 restore_flags(flags
);
807 if (request_irq(dz_ports
[0].port
.irq
, dz_interrupt
,
808 SA_INTERRUPT
, "DZ", &dz_ports
[0]))
809 panic("Unable to register DZ interrupt");
811 ret
= uart_register_driver(&dz_reg
);
815 for (i
= 0; i
< DZ_NB_PORT
; i
++)
816 uart_add_one_port(&dz_reg
, &dz_ports
[i
].port
);
821 MODULE_DESCRIPTION("DECstation DZ serial driver");
822 MODULE_LICENSE("GPL");