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1da177e4 LT |
1 | /* |
2 | * C-Brick Serial Port (and console) driver for SGI Altix machines. | |
3 | * | |
4 | * This driver is NOT suitable for talking to the l1-controller for | |
5 | * anything other than 'console activities' --- please use the l1 | |
6 | * driver for that. | |
7 | * | |
8 | * | |
d171e519 | 9 | * Copyright (c) 2004-2006 Silicon Graphics, Inc. All Rights Reserved. |
1da177e4 LT |
10 | * |
11 | * This program is free software; you can redistribute it and/or modify it | |
12 | * under the terms of version 2 of the GNU General Public License | |
13 | * as published by the Free Software Foundation. | |
14 | * | |
15 | * This program is distributed in the hope that it would be useful, but | |
16 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
18 | * | |
19 | * Further, this software is distributed without any warranty that it is | |
20 | * free of the rightful claim of any third person regarding infringement | |
21 | * or the like. Any license provided herein, whether implied or | |
22 | * otherwise, applies only to this software file. Patent licenses, if | |
23 | * any, provided herein do not apply to combinations of this program with | |
24 | * other software, or any other product whatsoever. | |
25 | * | |
26 | * You should have received a copy of the GNU General Public | |
27 | * License along with this program; if not, write the Free Software | |
28 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. | |
29 | * | |
30 | * Contact information: Silicon Graphics, Inc., 1500 Crittenden Lane, | |
31 | * Mountain View, CA 94043, or: | |
32 | * | |
33 | * http://www.sgi.com | |
34 | * | |
35 | * For further information regarding this notice, see: | |
36 | * | |
37 | * http://oss.sgi.com/projects/GenInfo/NoticeExplan | |
38 | */ | |
39 | ||
1da177e4 LT |
40 | #include <linux/interrupt.h> |
41 | #include <linux/tty.h> | |
42 | #include <linux/serial.h> | |
43 | #include <linux/console.h> | |
44 | #include <linux/module.h> | |
45 | #include <linux/sysrq.h> | |
46 | #include <linux/circ_buf.h> | |
47 | #include <linux/serial_reg.h> | |
48 | #include <linux/delay.h> /* for mdelay */ | |
49 | #include <linux/miscdevice.h> | |
50 | #include <linux/serial_core.h> | |
51 | ||
52 | #include <asm/io.h> | |
53 | #include <asm/sn/simulator.h> | |
54 | #include <asm/sn/sn_sal.h> | |
55 | ||
56 | /* number of characters we can transmit to the SAL console at a time */ | |
57 | #define SN_SAL_MAX_CHARS 120 | |
58 | ||
59 | /* 64K, when we're asynch, it must be at least printk's LOG_BUF_LEN to | |
60 | * avoid losing chars, (always has to be a power of 2) */ | |
61 | #define SN_SAL_BUFFER_SIZE (64 * (1 << 10)) | |
62 | ||
63 | #define SN_SAL_UART_FIFO_DEPTH 16 | |
1f3ccaed | 64 | #define SN_SAL_UART_FIFO_SPEED_CPS (9600/10) |
1da177e4 LT |
65 | |
66 | /* sn_transmit_chars() calling args */ | |
67 | #define TRANSMIT_BUFFERED 0 | |
68 | #define TRANSMIT_RAW 1 | |
69 | ||
70 | /* To use dynamic numbers only and not use the assigned major and minor, | |
71 | * define the following.. */ | |
72 | /* #define USE_DYNAMIC_MINOR 1 *//* use dynamic minor number */ | |
73 | #define USE_DYNAMIC_MINOR 0 /* Don't rely on misc_register dynamic minor */ | |
74 | ||
75 | /* Device name we're using */ | |
76 | #define DEVICE_NAME "ttySG" | |
77 | #define DEVICE_NAME_DYNAMIC "ttySG0" /* need full name for misc_register */ | |
78 | /* The major/minor we are using, ignored for USE_DYNAMIC_MINOR */ | |
79 | #define DEVICE_MAJOR 204 | |
80 | #define DEVICE_MINOR 40 | |
81 | ||
82 | #ifdef CONFIG_MAGIC_SYSRQ | |
83 | static char sysrq_serial_str[] = "\eSYS"; | |
84 | static char *sysrq_serial_ptr = sysrq_serial_str; | |
85 | static unsigned long sysrq_requested; | |
86 | #endif /* CONFIG_MAGIC_SYSRQ */ | |
87 | ||
88 | /* | |
89 | * Port definition - this kinda drives it all | |
90 | */ | |
91 | struct sn_cons_port { | |
92 | struct timer_list sc_timer; | |
93 | struct uart_port sc_port; | |
94 | struct sn_sal_ops { | |
95 | int (*sal_puts_raw) (const char *s, int len); | |
96 | int (*sal_puts) (const char *s, int len); | |
97 | int (*sal_getc) (void); | |
98 | int (*sal_input_pending) (void); | |
99 | void (*sal_wakeup_transmit) (struct sn_cons_port *, int); | |
100 | } *sc_ops; | |
101 | unsigned long sc_interrupt_timeout; | |
102 | int sc_is_asynch; | |
103 | }; | |
104 | ||
105 | static struct sn_cons_port sal_console_port; | |
106 | static int sn_process_input; | |
107 | ||
108 | /* Only used if USE_DYNAMIC_MINOR is set to 1 */ | |
109 | static struct miscdevice misc; /* used with misc_register for dynamic */ | |
110 | ||
111 | extern void early_sn_setup(void); | |
112 | ||
113 | #undef DEBUG | |
114 | #ifdef DEBUG | |
115 | static int sn_debug_printf(const char *fmt, ...); | |
116 | #define DPRINTF(x...) sn_debug_printf(x) | |
117 | #else | |
118 | #define DPRINTF(x...) do { } while (0) | |
119 | #endif | |
120 | ||
121 | /* Prototypes */ | |
122 | static int snt_hw_puts_raw(const char *, int); | |
123 | static int snt_hw_puts_buffered(const char *, int); | |
124 | static int snt_poll_getc(void); | |
125 | static int snt_poll_input_pending(void); | |
126 | static int snt_intr_getc(void); | |
127 | static int snt_intr_input_pending(void); | |
128 | static void sn_transmit_chars(struct sn_cons_port *, int); | |
129 | ||
130 | /* A table for polling: | |
131 | */ | |
132 | static struct sn_sal_ops poll_ops = { | |
133 | .sal_puts_raw = snt_hw_puts_raw, | |
134 | .sal_puts = snt_hw_puts_raw, | |
135 | .sal_getc = snt_poll_getc, | |
136 | .sal_input_pending = snt_poll_input_pending | |
137 | }; | |
138 | ||
139 | /* A table for interrupts enabled */ | |
140 | static struct sn_sal_ops intr_ops = { | |
141 | .sal_puts_raw = snt_hw_puts_raw, | |
142 | .sal_puts = snt_hw_puts_buffered, | |
143 | .sal_getc = snt_intr_getc, | |
144 | .sal_input_pending = snt_intr_input_pending, | |
145 | .sal_wakeup_transmit = sn_transmit_chars | |
146 | }; | |
147 | ||
148 | /* the console does output in two distinctly different ways: | |
149 | * synchronous (raw) and asynchronous (buffered). initally, early_printk | |
150 | * does synchronous output. any data written goes directly to the SAL | |
151 | * to be output (incidentally, it is internally buffered by the SAL) | |
152 | * after interrupts and timers are initialized and available for use, | |
153 | * the console init code switches to asynchronous output. this is | |
154 | * also the earliest opportunity to begin polling for console input. | |
155 | * after console initialization, console output and tty (serial port) | |
156 | * output is buffered and sent to the SAL asynchronously (either by | |
157 | * timer callback or by UART interrupt) */ | |
158 | ||
159 | /* routines for running the console in polling mode */ | |
160 | ||
161 | /** | |
162 | * snt_poll_getc - Get a character from the console in polling mode | |
163 | * | |
164 | */ | |
165 | static int snt_poll_getc(void) | |
166 | { | |
167 | int ch; | |
168 | ||
169 | ia64_sn_console_getc(&ch); | |
170 | return ch; | |
171 | } | |
172 | ||
173 | /** | |
174 | * snt_poll_input_pending - Check if any input is waiting - polling mode. | |
175 | * | |
176 | */ | |
177 | static int snt_poll_input_pending(void) | |
178 | { | |
179 | int status, input; | |
180 | ||
181 | status = ia64_sn_console_check(&input); | |
182 | return !status && input; | |
183 | } | |
184 | ||
185 | /* routines for an interrupt driven console (normal) */ | |
186 | ||
187 | /** | |
188 | * snt_intr_getc - Get a character from the console, interrupt mode | |
189 | * | |
190 | */ | |
191 | static int snt_intr_getc(void) | |
192 | { | |
193 | return ia64_sn_console_readc(); | |
194 | } | |
195 | ||
196 | /** | |
197 | * snt_intr_input_pending - Check if input is pending, interrupt mode | |
198 | * | |
199 | */ | |
200 | static int snt_intr_input_pending(void) | |
201 | { | |
202 | return ia64_sn_console_intr_status() & SAL_CONSOLE_INTR_RECV; | |
203 | } | |
204 | ||
205 | /* these functions are polled and interrupt */ | |
206 | ||
207 | /** | |
208 | * snt_hw_puts_raw - Send raw string to the console, polled or interrupt mode | |
209 | * @s: String | |
210 | * @len: Length | |
211 | * | |
212 | */ | |
213 | static int snt_hw_puts_raw(const char *s, int len) | |
214 | { | |
215 | /* this will call the PROM and not return until this is done */ | |
216 | return ia64_sn_console_putb(s, len); | |
217 | } | |
218 | ||
219 | /** | |
220 | * snt_hw_puts_buffered - Send string to console, polled or interrupt mode | |
221 | * @s: String | |
222 | * @len: Length | |
223 | * | |
224 | */ | |
225 | static int snt_hw_puts_buffered(const char *s, int len) | |
226 | { | |
227 | /* queue data to the PROM */ | |
228 | return ia64_sn_console_xmit_chars((char *)s, len); | |
229 | } | |
230 | ||
231 | /* uart interface structs | |
232 | * These functions are associated with the uart_port that the serial core | |
233 | * infrastructure calls. | |
234 | * | |
235 | * Note: Due to how the console works, many routines are no-ops. | |
236 | */ | |
237 | ||
238 | /** | |
239 | * snp_type - What type of console are we? | |
240 | * @port: Port to operate with (we ignore since we only have one port) | |
241 | * | |
242 | */ | |
243 | static const char *snp_type(struct uart_port *port) | |
244 | { | |
245 | return ("SGI SN L1"); | |
246 | } | |
247 | ||
248 | /** | |
249 | * snp_tx_empty - Is the transmitter empty? We pretend we're always empty | |
250 | * @port: Port to operate on (we ignore since we only have one port) | |
251 | * | |
252 | */ | |
253 | static unsigned int snp_tx_empty(struct uart_port *port) | |
254 | { | |
255 | return 1; | |
256 | } | |
257 | ||
258 | /** | |
259 | * snp_stop_tx - stop the transmitter - no-op for us | |
260 | * @port: Port to operat eon - we ignore - no-op function | |
1da177e4 LT |
261 | * |
262 | */ | |
b129a8cc | 263 | static void snp_stop_tx(struct uart_port *port) |
1da177e4 LT |
264 | { |
265 | } | |
266 | ||
267 | /** | |
268 | * snp_release_port - Free i/o and resources for port - no-op for us | |
269 | * @port: Port to operate on - we ignore - no-op function | |
270 | * | |
271 | */ | |
272 | static void snp_release_port(struct uart_port *port) | |
273 | { | |
274 | } | |
275 | ||
276 | /** | |
277 | * snp_enable_ms - Force modem status interrupts on - no-op for us | |
278 | * @port: Port to operate on - we ignore - no-op function | |
279 | * | |
280 | */ | |
281 | static void snp_enable_ms(struct uart_port *port) | |
282 | { | |
283 | } | |
284 | ||
285 | /** | |
286 | * snp_shutdown - shut down the port - free irq and disable - no-op for us | |
287 | * @port: Port to shut down - we ignore | |
288 | * | |
289 | */ | |
290 | static void snp_shutdown(struct uart_port *port) | |
291 | { | |
292 | } | |
293 | ||
294 | /** | |
295 | * snp_set_mctrl - set control lines (dtr, rts, etc) - no-op for our console | |
296 | * @port: Port to operate on - we ignore | |
297 | * @mctrl: Lines to set/unset - we ignore | |
298 | * | |
299 | */ | |
300 | static void snp_set_mctrl(struct uart_port *port, unsigned int mctrl) | |
301 | { | |
302 | } | |
303 | ||
304 | /** | |
305 | * snp_get_mctrl - get contorl line info, we just return a static value | |
306 | * @port: port to operate on - we only have one port so we ignore this | |
307 | * | |
308 | */ | |
309 | static unsigned int snp_get_mctrl(struct uart_port *port) | |
310 | { | |
311 | return TIOCM_CAR | TIOCM_RNG | TIOCM_DSR | TIOCM_CTS; | |
312 | } | |
313 | ||
314 | /** | |
315 | * snp_stop_rx - Stop the receiver - we ignor ethis | |
316 | * @port: Port to operate on - we ignore | |
317 | * | |
318 | */ | |
319 | static void snp_stop_rx(struct uart_port *port) | |
320 | { | |
321 | } | |
322 | ||
323 | /** | |
324 | * snp_start_tx - Start transmitter | |
325 | * @port: Port to operate on | |
1da177e4 LT |
326 | * |
327 | */ | |
b129a8cc | 328 | static void snp_start_tx(struct uart_port *port) |
1da177e4 LT |
329 | { |
330 | if (sal_console_port.sc_ops->sal_wakeup_transmit) | |
331 | sal_console_port.sc_ops->sal_wakeup_transmit(&sal_console_port, | |
332 | TRANSMIT_BUFFERED); | |
333 | ||
334 | } | |
335 | ||
336 | /** | |
337 | * snp_break_ctl - handle breaks - ignored by us | |
338 | * @port: Port to operate on | |
339 | * @break_state: Break state | |
340 | * | |
341 | */ | |
342 | static void snp_break_ctl(struct uart_port *port, int break_state) | |
343 | { | |
344 | } | |
345 | ||
346 | /** | |
347 | * snp_startup - Start up the serial port - always return 0 (We're always on) | |
348 | * @port: Port to operate on | |
349 | * | |
350 | */ | |
351 | static int snp_startup(struct uart_port *port) | |
352 | { | |
353 | return 0; | |
354 | } | |
355 | ||
356 | /** | |
357 | * snp_set_termios - set termios stuff - we ignore these | |
358 | * @port: port to operate on | |
359 | * @termios: New settings | |
360 | * @termios: Old | |
361 | * | |
362 | */ | |
363 | static void | |
606d099c AC |
364 | snp_set_termios(struct uart_port *port, struct ktermios *termios, |
365 | struct ktermios *old) | |
1da177e4 LT |
366 | { |
367 | } | |
368 | ||
369 | /** | |
370 | * snp_request_port - allocate resources for port - ignored by us | |
371 | * @port: port to operate on | |
372 | * | |
373 | */ | |
374 | static int snp_request_port(struct uart_port *port) | |
375 | { | |
376 | return 0; | |
377 | } | |
378 | ||
379 | /** | |
380 | * snp_config_port - allocate resources, set up - we ignore, we're always on | |
381 | * @port: Port to operate on | |
382 | * @flags: flags used for port setup | |
383 | * | |
384 | */ | |
385 | static void snp_config_port(struct uart_port *port, int flags) | |
386 | { | |
387 | } | |
388 | ||
389 | /* Associate the uart functions above - given to serial core */ | |
390 | ||
391 | static struct uart_ops sn_console_ops = { | |
392 | .tx_empty = snp_tx_empty, | |
393 | .set_mctrl = snp_set_mctrl, | |
394 | .get_mctrl = snp_get_mctrl, | |
395 | .stop_tx = snp_stop_tx, | |
396 | .start_tx = snp_start_tx, | |
397 | .stop_rx = snp_stop_rx, | |
398 | .enable_ms = snp_enable_ms, | |
399 | .break_ctl = snp_break_ctl, | |
400 | .startup = snp_startup, | |
401 | .shutdown = snp_shutdown, | |
402 | .set_termios = snp_set_termios, | |
403 | .pm = NULL, | |
404 | .type = snp_type, | |
405 | .release_port = snp_release_port, | |
406 | .request_port = snp_request_port, | |
407 | .config_port = snp_config_port, | |
408 | .verify_port = NULL, | |
409 | }; | |
410 | ||
411 | /* End of uart struct functions and defines */ | |
412 | ||
413 | #ifdef DEBUG | |
414 | ||
415 | /** | |
416 | * sn_debug_printf - close to hardware debugging printf | |
417 | * @fmt: printf format | |
418 | * | |
419 | * This is as "close to the metal" as we can get, used when the driver | |
420 | * itself may be broken. | |
421 | * | |
422 | */ | |
423 | static int sn_debug_printf(const char *fmt, ...) | |
424 | { | |
425 | static char printk_buf[1024]; | |
426 | int printed_len; | |
427 | va_list args; | |
428 | ||
429 | va_start(args, fmt); | |
430 | printed_len = vsnprintf(printk_buf, sizeof(printk_buf), fmt, args); | |
431 | ||
432 | if (!sal_console_port.sc_ops) { | |
433 | sal_console_port.sc_ops = &poll_ops; | |
434 | early_sn_setup(); | |
435 | } | |
436 | sal_console_port.sc_ops->sal_puts_raw(printk_buf, printed_len); | |
437 | ||
438 | va_end(args); | |
439 | return printed_len; | |
440 | } | |
441 | #endif /* DEBUG */ | |
442 | ||
443 | /* | |
444 | * Interrupt handling routines. | |
445 | */ | |
446 | ||
447 | /** | |
448 | * sn_receive_chars - Grab characters, pass them to tty layer | |
449 | * @port: Port to operate on | |
1da177e4 LT |
450 | * @flags: irq flags |
451 | * | |
452 | * Note: If we're not registered with the serial core infrastructure yet, | |
453 | * we don't try to send characters to it... | |
454 | * | |
455 | */ | |
456 | static void | |
7d12e780 | 457 | sn_receive_chars(struct sn_cons_port *port, unsigned long flags) |
1da177e4 LT |
458 | { |
459 | int ch; | |
460 | struct tty_struct *tty; | |
461 | ||
462 | if (!port) { | |
463 | printk(KERN_ERR "sn_receive_chars - port NULL so can't receieve\n"); | |
464 | return; | |
465 | } | |
466 | ||
467 | if (!port->sc_ops) { | |
468 | printk(KERN_ERR "sn_receive_chars - port->sc_ops NULL so can't receieve\n"); | |
469 | return; | |
470 | } | |
471 | ||
ebd2c8f6 | 472 | if (port->sc_port.state) { |
1da177e4 | 473 | /* The serial_core stuffs are initilized, use them */ |
ebd2c8f6 | 474 | tty = port->sc_port.state->port.tty; |
1da177e4 LT |
475 | } |
476 | else { | |
477 | /* Not registered yet - can't pass to tty layer. */ | |
478 | tty = NULL; | |
479 | } | |
480 | ||
481 | while (port->sc_ops->sal_input_pending()) { | |
482 | ch = port->sc_ops->sal_getc(); | |
483 | if (ch < 0) { | |
484 | printk(KERN_ERR "sn_console: An error occured while " | |
485 | "obtaining data from the console (0x%0x)\n", ch); | |
486 | break; | |
487 | } | |
488 | #ifdef CONFIG_MAGIC_SYSRQ | |
489 | if (sysrq_requested) { | |
490 | unsigned long sysrq_timeout = sysrq_requested + HZ*5; | |
491 | ||
492 | sysrq_requested = 0; | |
493 | if (ch && time_before(jiffies, sysrq_timeout)) { | |
494 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
7d12e780 | 495 | handle_sysrq(ch, NULL); |
1da177e4 LT |
496 | spin_lock_irqsave(&port->sc_port.lock, flags); |
497 | /* ignore actual sysrq command char */ | |
498 | continue; | |
499 | } | |
500 | } | |
501 | if (ch == *sysrq_serial_ptr) { | |
502 | if (!(*++sysrq_serial_ptr)) { | |
503 | sysrq_requested = jiffies; | |
504 | sysrq_serial_ptr = sysrq_serial_str; | |
505 | } | |
506 | /* | |
507 | * ignore the whole sysrq string except for the | |
508 | * leading escape | |
509 | */ | |
510 | if (ch != '\e') | |
511 | continue; | |
512 | } | |
513 | else | |
514 | sysrq_serial_ptr = sysrq_serial_str; | |
515 | #endif /* CONFIG_MAGIC_SYSRQ */ | |
516 | ||
517 | /* record the character to pass up to the tty layer */ | |
518 | if (tty) { | |
33f0f88f | 519 | if(tty_insert_flip_char(tty, ch, TTY_NORMAL) == 0) |
1da177e4 LT |
520 | break; |
521 | } | |
522 | port->sc_port.icount.rx++; | |
523 | } | |
524 | ||
525 | if (tty) | |
526 | tty_flip_buffer_push(tty); | |
527 | } | |
528 | ||
529 | /** | |
530 | * sn_transmit_chars - grab characters from serial core, send off | |
531 | * @port: Port to operate on | |
532 | * @raw: Transmit raw or buffered | |
533 | * | |
534 | * Note: If we're early, before we're registered with serial core, the | |
535 | * writes are going through sn_sal_console_write because that's how | |
536 | * register_console has been set up. We currently could have asynch | |
537 | * polls calling this function due to sn_sal_switch_to_asynch but we can | |
538 | * ignore them until we register with the serial core stuffs. | |
539 | * | |
540 | */ | |
541 | static void sn_transmit_chars(struct sn_cons_port *port, int raw) | |
542 | { | |
543 | int xmit_count, tail, head, loops, ii; | |
544 | int result; | |
545 | char *start; | |
546 | struct circ_buf *xmit; | |
547 | ||
548 | if (!port) | |
549 | return; | |
550 | ||
551 | BUG_ON(!port->sc_is_asynch); | |
552 | ||
ebd2c8f6 | 553 | if (port->sc_port.state) { |
1da177e4 | 554 | /* We're initilized, using serial core infrastructure */ |
ebd2c8f6 | 555 | xmit = &port->sc_port.state->xmit; |
1da177e4 LT |
556 | } else { |
557 | /* Probably sn_sal_switch_to_asynch has been run but serial core isn't | |
558 | * initilized yet. Just return. Writes are going through | |
559 | * sn_sal_console_write (due to register_console) at this time. | |
560 | */ | |
561 | return; | |
562 | } | |
563 | ||
564 | if (uart_circ_empty(xmit) || uart_tx_stopped(&port->sc_port)) { | |
565 | /* Nothing to do. */ | |
328007b7 | 566 | ia64_sn_console_intr_disable(SAL_CONSOLE_INTR_XMIT); |
1da177e4 LT |
567 | return; |
568 | } | |
569 | ||
570 | head = xmit->head; | |
571 | tail = xmit->tail; | |
572 | start = &xmit->buf[tail]; | |
573 | ||
574 | /* twice around gets the tail to the end of the buffer and | |
575 | * then to the head, if needed */ | |
576 | loops = (head < tail) ? 2 : 1; | |
577 | ||
578 | for (ii = 0; ii < loops; ii++) { | |
579 | xmit_count = (head < tail) ? | |
580 | (UART_XMIT_SIZE - tail) : (head - tail); | |
581 | ||
582 | if (xmit_count > 0) { | |
583 | if (raw == TRANSMIT_RAW) | |
584 | result = | |
585 | port->sc_ops->sal_puts_raw(start, | |
586 | xmit_count); | |
587 | else | |
588 | result = | |
589 | port->sc_ops->sal_puts(start, xmit_count); | |
590 | #ifdef DEBUG | |
591 | if (!result) | |
592 | DPRINTF("`"); | |
593 | #endif | |
594 | if (result > 0) { | |
595 | xmit_count -= result; | |
596 | port->sc_port.icount.tx += result; | |
597 | tail += result; | |
598 | tail &= UART_XMIT_SIZE - 1; | |
599 | xmit->tail = tail; | |
600 | start = &xmit->buf[tail]; | |
601 | } | |
602 | } | |
603 | } | |
604 | ||
605 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) | |
606 | uart_write_wakeup(&port->sc_port); | |
607 | ||
608 | if (uart_circ_empty(xmit)) | |
b129a8cc | 609 | snp_stop_tx(&port->sc_port); /* no-op for us */ |
1da177e4 LT |
610 | } |
611 | ||
612 | /** | |
613 | * sn_sal_interrupt - Handle console interrupts | |
614 | * @irq: irq #, useful for debug statements | |
615 | * @dev_id: our pointer to our port (sn_cons_port which contains the uart port) | |
1da177e4 LT |
616 | * |
617 | */ | |
7d12e780 | 618 | static irqreturn_t sn_sal_interrupt(int irq, void *dev_id) |
1da177e4 LT |
619 | { |
620 | struct sn_cons_port *port = (struct sn_cons_port *)dev_id; | |
621 | unsigned long flags; | |
622 | int status = ia64_sn_console_intr_status(); | |
623 | ||
624 | if (!port) | |
625 | return IRQ_NONE; | |
626 | ||
627 | spin_lock_irqsave(&port->sc_port.lock, flags); | |
628 | if (status & SAL_CONSOLE_INTR_RECV) { | |
7d12e780 | 629 | sn_receive_chars(port, flags); |
1da177e4 LT |
630 | } |
631 | if (status & SAL_CONSOLE_INTR_XMIT) { | |
632 | sn_transmit_chars(port, TRANSMIT_BUFFERED); | |
633 | } | |
634 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
635 | return IRQ_HANDLED; | |
636 | } | |
637 | ||
1da177e4 LT |
638 | /** |
639 | * sn_sal_timer_poll - this function handles polled console mode | |
640 | * @data: A pointer to our sn_cons_port (which contains the uart port) | |
641 | * | |
642 | * data is the pointer that init_timer will store for us. This function is | |
643 | * associated with init_timer to see if there is any console traffic. | |
644 | * Obviously not used in interrupt mode | |
645 | * | |
646 | */ | |
647 | static void sn_sal_timer_poll(unsigned long data) | |
648 | { | |
649 | struct sn_cons_port *port = (struct sn_cons_port *)data; | |
650 | unsigned long flags; | |
651 | ||
652 | if (!port) | |
653 | return; | |
654 | ||
655 | if (!port->sc_port.irq) { | |
656 | spin_lock_irqsave(&port->sc_port.lock, flags); | |
657 | if (sn_process_input) | |
8c1addbc | 658 | sn_receive_chars(port, flags); |
1da177e4 LT |
659 | sn_transmit_chars(port, TRANSMIT_RAW); |
660 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
661 | mod_timer(&port->sc_timer, | |
662 | jiffies + port->sc_interrupt_timeout); | |
663 | } | |
664 | } | |
665 | ||
666 | /* | |
667 | * Boot-time initialization code | |
668 | */ | |
669 | ||
670 | /** | |
671 | * sn_sal_switch_to_asynch - Switch to async mode (as opposed to synch) | |
672 | * @port: Our sn_cons_port (which contains the uart port) | |
673 | * | |
674 | * So this is used by sn_sal_serial_console_init (early on, before we're | |
675 | * registered with serial core). It's also used by sn_sal_module_init | |
676 | * right after we've registered with serial core. The later only happens | |
677 | * if we didn't already come through here via sn_sal_serial_console_init. | |
678 | * | |
679 | */ | |
680 | static void __init sn_sal_switch_to_asynch(struct sn_cons_port *port) | |
681 | { | |
682 | unsigned long flags; | |
683 | ||
684 | if (!port) | |
685 | return; | |
686 | ||
687 | DPRINTF("sn_console: about to switch to asynchronous console\n"); | |
688 | ||
689 | /* without early_printk, we may be invoked late enough to race | |
690 | * with other cpus doing console IO at this point, however | |
691 | * console interrupts will never be enabled */ | |
692 | spin_lock_irqsave(&port->sc_port.lock, flags); | |
693 | ||
694 | /* early_printk invocation may have done this for us */ | |
695 | if (!port->sc_ops) | |
696 | port->sc_ops = &poll_ops; | |
697 | ||
698 | /* we can't turn on the console interrupt (as request_irq | |
699 | * calls kmalloc, which isn't set up yet), so we rely on a | |
700 | * timer to poll for input and push data from the console | |
701 | * buffer. | |
702 | */ | |
703 | init_timer(&port->sc_timer); | |
704 | port->sc_timer.function = sn_sal_timer_poll; | |
705 | port->sc_timer.data = (unsigned long)port; | |
706 | ||
707 | if (IS_RUNNING_ON_SIMULATOR()) | |
708 | port->sc_interrupt_timeout = 6; | |
709 | else { | |
710 | /* 960cps / 16 char FIFO = 60HZ | |
711 | * HZ / (SN_SAL_FIFO_SPEED_CPS / SN_SAL_FIFO_DEPTH) */ | |
712 | port->sc_interrupt_timeout = | |
713 | HZ * SN_SAL_UART_FIFO_DEPTH / SN_SAL_UART_FIFO_SPEED_CPS; | |
714 | } | |
715 | mod_timer(&port->sc_timer, jiffies + port->sc_interrupt_timeout); | |
716 | ||
717 | port->sc_is_asynch = 1; | |
718 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
719 | } | |
720 | ||
721 | /** | |
722 | * sn_sal_switch_to_interrupts - Switch to interrupt driven mode | |
723 | * @port: Our sn_cons_port (which contains the uart port) | |
724 | * | |
725 | * In sn_sal_module_init, after we're registered with serial core and | |
726 | * the port is added, this function is called to switch us to interrupt | |
727 | * mode. We were previously in asynch/polling mode (using init_timer). | |
728 | * | |
729 | * We attempt to switch to interrupt mode here by calling | |
f70c81d4 | 730 | * request_irq. If that works out, we enable receive interrupts. |
1da177e4 LT |
731 | */ |
732 | static void __init sn_sal_switch_to_interrupts(struct sn_cons_port *port) | |
733 | { | |
1da177e4 LT |
734 | unsigned long flags; |
735 | ||
f70c81d4 PG |
736 | if (port) { |
737 | DPRINTF("sn_console: switching to interrupt driven console\n"); | |
1da177e4 | 738 | |
f70c81d4 PG |
739 | if (request_irq(SGI_UART_VECTOR, sn_sal_interrupt, |
740 | IRQF_DISABLED | IRQF_SHARED, | |
741 | "SAL console driver", port) >= 0) { | |
742 | spin_lock_irqsave(&port->sc_port.lock, flags); | |
743 | port->sc_port.irq = SGI_UART_VECTOR; | |
744 | port->sc_ops = &intr_ops; | |
1da177e4 | 745 | |
f70c81d4 PG |
746 | /* turn on receive interrupts */ |
747 | ia64_sn_console_intr_enable(SAL_CONSOLE_INTR_RECV); | |
748 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
749 | } | |
750 | else { | |
751 | printk(KERN_INFO | |
752 | "sn_console: console proceeding in polled mode\n"); | |
753 | } | |
1da177e4 | 754 | } |
1da177e4 LT |
755 | } |
756 | ||
757 | /* | |
758 | * Kernel console definitions | |
759 | */ | |
760 | ||
761 | static void sn_sal_console_write(struct console *, const char *, unsigned); | |
17e0c7cc | 762 | static int sn_sal_console_setup(struct console *, char *); |
434498d5 | 763 | static struct uart_driver sal_console_uart; |
1da177e4 LT |
764 | extern struct tty_driver *uart_console_device(struct console *, int *); |
765 | ||
766 | static struct console sal_console = { | |
767 | .name = DEVICE_NAME, | |
768 | .write = sn_sal_console_write, | |
769 | .device = uart_console_device, | |
770 | .setup = sn_sal_console_setup, | |
771 | .index = -1, /* unspecified */ | |
772 | .data = &sal_console_uart, | |
773 | }; | |
774 | ||
775 | #define SAL_CONSOLE &sal_console | |
776 | ||
434498d5 | 777 | static struct uart_driver sal_console_uart = { |
1da177e4 LT |
778 | .owner = THIS_MODULE, |
779 | .driver_name = "sn_console", | |
780 | .dev_name = DEVICE_NAME, | |
781 | .major = 0, /* major/minor set at registration time per USE_DYNAMIC_MINOR */ | |
782 | .minor = 0, | |
783 | .nr = 1, /* one port */ | |
784 | .cons = SAL_CONSOLE, | |
785 | }; | |
786 | ||
787 | /** | |
788 | * sn_sal_module_init - When the kernel loads us, get us rolling w/ serial core | |
789 | * | |
790 | * Before this is called, we've been printing kernel messages in a special | |
791 | * early mode not making use of the serial core infrastructure. When our | |
792 | * driver is loaded for real, we register the driver and port with serial | |
793 | * core and try to enable interrupt driven mode. | |
794 | * | |
795 | */ | |
796 | static int __init sn_sal_module_init(void) | |
797 | { | |
798 | int retval; | |
799 | ||
800 | if (!ia64_platform_is("sn2")) | |
f032f908 | 801 | return 0; |
1da177e4 LT |
802 | |
803 | printk(KERN_INFO "sn_console: Console driver init\n"); | |
804 | ||
805 | if (USE_DYNAMIC_MINOR == 1) { | |
806 | misc.minor = MISC_DYNAMIC_MINOR; | |
807 | misc.name = DEVICE_NAME_DYNAMIC; | |
808 | retval = misc_register(&misc); | |
809 | if (retval != 0) { | |
d171e519 JS |
810 | printk(KERN_WARNING "Failed to register console " |
811 | "device using misc_register.\n"); | |
1da177e4 LT |
812 | return -ENODEV; |
813 | } | |
814 | sal_console_uart.major = MISC_MAJOR; | |
815 | sal_console_uart.minor = misc.minor; | |
816 | } else { | |
817 | sal_console_uart.major = DEVICE_MAJOR; | |
818 | sal_console_uart.minor = DEVICE_MINOR; | |
819 | } | |
820 | ||
821 | /* We register the driver and the port before switching to interrupts | |
822 | * or async above so the proper uart structures are populated */ | |
823 | ||
824 | if (uart_register_driver(&sal_console_uart) < 0) { | |
825 | printk | |
826 | ("ERROR sn_sal_module_init failed uart_register_driver, line %d\n", | |
827 | __LINE__); | |
828 | return -ENODEV; | |
829 | } | |
830 | ||
831 | spin_lock_init(&sal_console_port.sc_port.lock); | |
832 | ||
833 | /* Setup the port struct with the minimum needed */ | |
834 | sal_console_port.sc_port.membase = (char *)1; /* just needs to be non-zero */ | |
835 | sal_console_port.sc_port.type = PORT_16550A; | |
836 | sal_console_port.sc_port.fifosize = SN_SAL_MAX_CHARS; | |
837 | sal_console_port.sc_port.ops = &sn_console_ops; | |
838 | sal_console_port.sc_port.line = 0; | |
839 | ||
840 | if (uart_add_one_port(&sal_console_uart, &sal_console_port.sc_port) < 0) { | |
841 | /* error - not sure what I'd do - so I'll do nothing */ | |
71cc2c21 | 842 | printk(KERN_ERR "%s: unable to add port\n", __func__); |
1da177e4 LT |
843 | } |
844 | ||
845 | /* when this driver is compiled in, the console initialization | |
846 | * will have already switched us into asynchronous operation | |
847 | * before we get here through the module initcalls */ | |
848 | if (!sal_console_port.sc_is_asynch) { | |
849 | sn_sal_switch_to_asynch(&sal_console_port); | |
850 | } | |
851 | ||
852 | /* at this point (module_init) we can try to turn on interrupts */ | |
853 | if (!IS_RUNNING_ON_SIMULATOR()) { | |
854 | sn_sal_switch_to_interrupts(&sal_console_port); | |
855 | } | |
856 | sn_process_input = 1; | |
857 | return 0; | |
858 | } | |
859 | ||
860 | /** | |
861 | * sn_sal_module_exit - When we're unloaded, remove the driver/port | |
862 | * | |
863 | */ | |
864 | static void __exit sn_sal_module_exit(void) | |
865 | { | |
866 | del_timer_sync(&sal_console_port.sc_timer); | |
867 | uart_remove_one_port(&sal_console_uart, &sal_console_port.sc_port); | |
868 | uart_unregister_driver(&sal_console_uart); | |
869 | misc_deregister(&misc); | |
870 | } | |
871 | ||
872 | module_init(sn_sal_module_init); | |
873 | module_exit(sn_sal_module_exit); | |
874 | ||
875 | /** | |
876 | * puts_raw_fixed - sn_sal_console_write helper for adding \r's as required | |
877 | * @puts_raw : puts function to do the writing | |
878 | * @s: input string | |
879 | * @count: length | |
880 | * | |
881 | * We need a \r ahead of every \n for direct writes through | |
882 | * ia64_sn_console_putb (what sal_puts_raw below actually does). | |
883 | * | |
884 | */ | |
885 | ||
886 | static void puts_raw_fixed(int (*puts_raw) (const char *s, int len), | |
887 | const char *s, int count) | |
888 | { | |
889 | const char *s1; | |
890 | ||
891 | /* Output '\r' before each '\n' */ | |
892 | while ((s1 = memchr(s, '\n', count)) != NULL) { | |
893 | puts_raw(s, s1 - s); | |
894 | puts_raw("\r\n", 2); | |
895 | count -= s1 + 1 - s; | |
896 | s = s1 + 1; | |
897 | } | |
898 | puts_raw(s, count); | |
899 | } | |
900 | ||
901 | /** | |
902 | * sn_sal_console_write - Print statements before serial core available | |
903 | * @console: Console to operate on - we ignore since we have just one | |
904 | * @s: String to send | |
905 | * @count: length | |
906 | * | |
907 | * This is referenced in the console struct. It is used for early | |
908 | * console printing before we register with serial core and for things | |
909 | * such as kdb. The console_lock must be held when we get here. | |
910 | * | |
911 | * This function has some code for trying to print output even if the lock | |
912 | * is held. We try to cover the case where a lock holder could have died. | |
913 | * We don't use this special case code if we're not registered with serial | |
914 | * core yet. After we're registered with serial core, the only time this | |
915 | * function would be used is for high level kernel output like magic sys req, | |
916 | * kdb, and printk's. | |
917 | */ | |
918 | static void | |
919 | sn_sal_console_write(struct console *co, const char *s, unsigned count) | |
920 | { | |
921 | unsigned long flags = 0; | |
922 | struct sn_cons_port *port = &sal_console_port; | |
1da177e4 | 923 | static int stole_lock = 0; |
1da177e4 LT |
924 | |
925 | BUG_ON(!port->sc_is_asynch); | |
926 | ||
927 | /* We can't look at the xmit buffer if we're not registered with serial core | |
928 | * yet. So only do the fancy recovery after registering | |
929 | */ | |
ebd2c8f6 | 930 | if (!port->sc_port.state) { |
d171e519 JS |
931 | /* Not yet registered with serial core - simple case */ |
932 | puts_raw_fixed(port->sc_ops->sal_puts_raw, s, count); | |
933 | return; | |
934 | } | |
1da177e4 | 935 | |
d171e519 JS |
936 | /* somebody really wants this output, might be an |
937 | * oops, kdb, panic, etc. make sure they get it. */ | |
938 | if (spin_is_locked(&port->sc_port.lock)) { | |
ebd2c8f6 AC |
939 | int lhead = port->sc_port.state->xmit.head; |
940 | int ltail = port->sc_port.state->xmit.tail; | |
d171e519 JS |
941 | int counter, got_lock = 0; |
942 | ||
943 | /* | |
944 | * We attempt to determine if someone has died with the | |
945 | * lock. We wait ~20 secs after the head and tail ptrs | |
946 | * stop moving and assume the lock holder is not functional | |
947 | * and plow ahead. If the lock is freed within the time out | |
948 | * period we re-get the lock and go ahead normally. We also | |
949 | * remember if we have plowed ahead so that we don't have | |
950 | * to wait out the time out period again - the asumption | |
951 | * is that we will time out again. | |
952 | */ | |
1da177e4 | 953 | |
d171e519 JS |
954 | for (counter = 0; counter < 150; mdelay(125), counter++) { |
955 | if (!spin_is_locked(&port->sc_port.lock) | |
956 | || stole_lock) { | |
957 | if (!stole_lock) { | |
958 | spin_lock_irqsave(&port->sc_port.lock, | |
959 | flags); | |
960 | got_lock = 1; | |
1da177e4 | 961 | } |
d171e519 | 962 | break; |
1da177e4 | 963 | } else { |
d171e519 | 964 | /* still locked */ |
ebd2c8f6 | 965 | if ((lhead != port->sc_port.state->xmit.head) |
d171e519 | 966 | || (ltail != |
ebd2c8f6 | 967 | port->sc_port.state->xmit.tail)) { |
d171e519 | 968 | lhead = |
ebd2c8f6 | 969 | port->sc_port.state->xmit.head; |
d171e519 | 970 | ltail = |
ebd2c8f6 | 971 | port->sc_port.state->xmit.tail; |
d171e519 JS |
972 | counter = 0; |
973 | } | |
1da177e4 | 974 | } |
d171e519 JS |
975 | } |
976 | /* flush anything in the serial core xmit buffer, raw */ | |
977 | sn_transmit_chars(port, 1); | |
978 | if (got_lock) { | |
1da177e4 | 979 | spin_unlock_irqrestore(&port->sc_port.lock, flags); |
d171e519 JS |
980 | stole_lock = 0; |
981 | } else { | |
982 | /* fell thru */ | |
983 | stole_lock = 1; | |
1da177e4 | 984 | } |
d171e519 JS |
985 | puts_raw_fixed(port->sc_ops->sal_puts_raw, s, count); |
986 | } else { | |
987 | stole_lock = 0; | |
988 | spin_lock_irqsave(&port->sc_port.lock, flags); | |
989 | sn_transmit_chars(port, 1); | |
990 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
991 | ||
1da177e4 LT |
992 | puts_raw_fixed(port->sc_ops->sal_puts_raw, s, count); |
993 | } | |
994 | } | |
995 | ||
996 | ||
997 | /** | |
998 | * sn_sal_console_setup - Set up console for early printing | |
999 | * @co: Console to work with | |
1000 | * @options: Options to set | |
1001 | * | |
1002 | * Altix console doesn't do anything with baud rates, etc, anyway. | |
1003 | * | |
1004 | * This isn't required since not providing the setup function in the | |
1005 | * console struct is ok. However, other patches like KDB plop something | |
1006 | * here so providing it is easier. | |
1007 | * | |
1008 | */ | |
17e0c7cc | 1009 | static int sn_sal_console_setup(struct console *co, char *options) |
1da177e4 LT |
1010 | { |
1011 | return 0; | |
1012 | } | |
1013 | ||
1014 | /** | |
1015 | * sn_sal_console_write_early - simple early output routine | |
1016 | * @co - console struct | |
1017 | * @s - string to print | |
1018 | * @count - count | |
1019 | * | |
1020 | * Simple function to provide early output, before even | |
1021 | * sn_sal_serial_console_init is called. Referenced in the | |
1022 | * console struct registerd in sn_serial_console_early_setup. | |
1023 | * | |
1024 | */ | |
1025 | static void __init | |
1026 | sn_sal_console_write_early(struct console *co, const char *s, unsigned count) | |
1027 | { | |
1028 | puts_raw_fixed(sal_console_port.sc_ops->sal_puts_raw, s, count); | |
1029 | } | |
1030 | ||
1031 | /* Used for very early console printing - again, before | |
1032 | * sn_sal_serial_console_init is run */ | |
1033 | static struct console sal_console_early __initdata = { | |
1034 | .name = "sn_sal", | |
1035 | .write = sn_sal_console_write_early, | |
1036 | .flags = CON_PRINTBUFFER, | |
1037 | .index = -1, | |
1038 | }; | |
1039 | ||
1040 | /** | |
1041 | * sn_serial_console_early_setup - Sets up early console output support | |
1042 | * | |
1043 | * Register a console early on... This is for output before even | |
1044 | * sn_sal_serial_cosnole_init is called. This function is called from | |
1045 | * setup.c. This allows us to do really early polled writes. When | |
1046 | * sn_sal_serial_console_init is called, this console is unregistered | |
1047 | * and a new one registered. | |
1048 | */ | |
1049 | int __init sn_serial_console_early_setup(void) | |
1050 | { | |
1051 | if (!ia64_platform_is("sn2")) | |
1052 | return -1; | |
1053 | ||
1054 | sal_console_port.sc_ops = &poll_ops; | |
71841b8f | 1055 | spin_lock_init(&sal_console_port.sc_port.lock); |
1da177e4 LT |
1056 | early_sn_setup(); /* Find SAL entry points */ |
1057 | register_console(&sal_console_early); | |
1058 | ||
1059 | return 0; | |
1060 | } | |
1061 | ||
1062 | /** | |
1063 | * sn_sal_serial_console_init - Early console output - set up for register | |
1064 | * | |
1065 | * This function is called when regular console init happens. Because we | |
1066 | * support even earlier console output with sn_serial_console_early_setup | |
1067 | * (called from setup.c directly), this function unregisters the really | |
1068 | * early console. | |
1069 | * | |
1070 | * Note: Even if setup.c doesn't register sal_console_early, unregistering | |
1071 | * it here doesn't hurt anything. | |
1072 | * | |
1073 | */ | |
1074 | static int __init sn_sal_serial_console_init(void) | |
1075 | { | |
1076 | if (ia64_platform_is("sn2")) { | |
1077 | sn_sal_switch_to_asynch(&sal_console_port); | |
1078 | DPRINTF("sn_sal_serial_console_init : register console\n"); | |
1079 | register_console(&sal_console); | |
1080 | unregister_console(&sal_console_early); | |
1081 | } | |
1082 | return 0; | |
1083 | } | |
1084 | ||
1085 | console_initcall(sn_sal_serial_console_init); |