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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> | |
ee160a38 | 42 | #include <linux/tty_flip.h> |
1da177e4 LT |
43 | #include <linux/serial.h> |
44 | #include <linux/console.h> | |
4e62794b | 45 | #include <linux/init.h> |
1da177e4 LT |
46 | #include <linux/sysrq.h> |
47 | #include <linux/circ_buf.h> | |
48 | #include <linux/serial_reg.h> | |
49 | #include <linux/delay.h> /* for mdelay */ | |
50 | #include <linux/miscdevice.h> | |
51 | #include <linux/serial_core.h> | |
52 | ||
53 | #include <asm/io.h> | |
54 | #include <asm/sn/simulator.h> | |
55 | #include <asm/sn/sn_sal.h> | |
56 | ||
57 | /* number of characters we can transmit to the SAL console at a time */ | |
58 | #define SN_SAL_MAX_CHARS 120 | |
59 | ||
60 | /* 64K, when we're asynch, it must be at least printk's LOG_BUF_LEN to | |
61 | * avoid losing chars, (always has to be a power of 2) */ | |
62 | #define SN_SAL_BUFFER_SIZE (64 * (1 << 10)) | |
63 | ||
64 | #define SN_SAL_UART_FIFO_DEPTH 16 | |
1f3ccaed | 65 | #define SN_SAL_UART_FIFO_SPEED_CPS (9600/10) |
1da177e4 LT |
66 | |
67 | /* sn_transmit_chars() calling args */ | |
68 | #define TRANSMIT_BUFFERED 0 | |
69 | #define TRANSMIT_RAW 1 | |
70 | ||
71 | /* To use dynamic numbers only and not use the assigned major and minor, | |
72 | * define the following.. */ | |
73 | /* #define USE_DYNAMIC_MINOR 1 *//* use dynamic minor number */ | |
74 | #define USE_DYNAMIC_MINOR 0 /* Don't rely on misc_register dynamic minor */ | |
75 | ||
76 | /* Device name we're using */ | |
77 | #define DEVICE_NAME "ttySG" | |
78 | #define DEVICE_NAME_DYNAMIC "ttySG0" /* need full name for misc_register */ | |
79 | /* The major/minor we are using, ignored for USE_DYNAMIC_MINOR */ | |
80 | #define DEVICE_MAJOR 204 | |
81 | #define DEVICE_MINOR 40 | |
82 | ||
83 | #ifdef CONFIG_MAGIC_SYSRQ | |
84 | static char sysrq_serial_str[] = "\eSYS"; | |
85 | static char *sysrq_serial_ptr = sysrq_serial_str; | |
86 | static unsigned long sysrq_requested; | |
87 | #endif /* CONFIG_MAGIC_SYSRQ */ | |
88 | ||
89 | /* | |
90 | * Port definition - this kinda drives it all | |
91 | */ | |
92 | struct sn_cons_port { | |
93 | struct timer_list sc_timer; | |
94 | struct uart_port sc_port; | |
95 | struct sn_sal_ops { | |
96 | int (*sal_puts_raw) (const char *s, int len); | |
97 | int (*sal_puts) (const char *s, int len); | |
98 | int (*sal_getc) (void); | |
99 | int (*sal_input_pending) (void); | |
100 | void (*sal_wakeup_transmit) (struct sn_cons_port *, int); | |
101 | } *sc_ops; | |
102 | unsigned long sc_interrupt_timeout; | |
103 | int sc_is_asynch; | |
104 | }; | |
105 | ||
106 | static struct sn_cons_port sal_console_port; | |
107 | static int sn_process_input; | |
108 | ||
109 | /* Only used if USE_DYNAMIC_MINOR is set to 1 */ | |
110 | static struct miscdevice misc; /* used with misc_register for dynamic */ | |
111 | ||
112 | extern void early_sn_setup(void); | |
113 | ||
114 | #undef DEBUG | |
115 | #ifdef DEBUG | |
116 | static int sn_debug_printf(const char *fmt, ...); | |
117 | #define DPRINTF(x...) sn_debug_printf(x) | |
118 | #else | |
119 | #define DPRINTF(x...) do { } while (0) | |
120 | #endif | |
121 | ||
122 | /* Prototypes */ | |
123 | static int snt_hw_puts_raw(const char *, int); | |
124 | static int snt_hw_puts_buffered(const char *, int); | |
125 | static int snt_poll_getc(void); | |
126 | static int snt_poll_input_pending(void); | |
127 | static int snt_intr_getc(void); | |
128 | static int snt_intr_input_pending(void); | |
129 | static void sn_transmit_chars(struct sn_cons_port *, int); | |
130 | ||
131 | /* A table for polling: | |
132 | */ | |
133 | static struct sn_sal_ops poll_ops = { | |
134 | .sal_puts_raw = snt_hw_puts_raw, | |
135 | .sal_puts = snt_hw_puts_raw, | |
136 | .sal_getc = snt_poll_getc, | |
137 | .sal_input_pending = snt_poll_input_pending | |
138 | }; | |
139 | ||
140 | /* A table for interrupts enabled */ | |
141 | static struct sn_sal_ops intr_ops = { | |
142 | .sal_puts_raw = snt_hw_puts_raw, | |
143 | .sal_puts = snt_hw_puts_buffered, | |
144 | .sal_getc = snt_intr_getc, | |
145 | .sal_input_pending = snt_intr_input_pending, | |
146 | .sal_wakeup_transmit = sn_transmit_chars | |
147 | }; | |
148 | ||
149 | /* the console does output in two distinctly different ways: | |
25985edc | 150 | * synchronous (raw) and asynchronous (buffered). initially, early_printk |
1da177e4 LT |
151 | * does synchronous output. any data written goes directly to the SAL |
152 | * to be output (incidentally, it is internally buffered by the SAL) | |
153 | * after interrupts and timers are initialized and available for use, | |
154 | * the console init code switches to asynchronous output. this is | |
155 | * also the earliest opportunity to begin polling for console input. | |
156 | * after console initialization, console output and tty (serial port) | |
157 | * output is buffered and sent to the SAL asynchronously (either by | |
158 | * timer callback or by UART interrupt) */ | |
159 | ||
160 | /* routines for running the console in polling mode */ | |
161 | ||
162 | /** | |
163 | * snt_poll_getc - Get a character from the console in polling mode | |
164 | * | |
165 | */ | |
166 | static int snt_poll_getc(void) | |
167 | { | |
168 | int ch; | |
169 | ||
170 | ia64_sn_console_getc(&ch); | |
171 | return ch; | |
172 | } | |
173 | ||
174 | /** | |
175 | * snt_poll_input_pending - Check if any input is waiting - polling mode. | |
176 | * | |
177 | */ | |
178 | static int snt_poll_input_pending(void) | |
179 | { | |
180 | int status, input; | |
181 | ||
182 | status = ia64_sn_console_check(&input); | |
183 | return !status && input; | |
184 | } | |
185 | ||
186 | /* routines for an interrupt driven console (normal) */ | |
187 | ||
188 | /** | |
189 | * snt_intr_getc - Get a character from the console, interrupt mode | |
190 | * | |
191 | */ | |
192 | static int snt_intr_getc(void) | |
193 | { | |
194 | return ia64_sn_console_readc(); | |
195 | } | |
196 | ||
197 | /** | |
198 | * snt_intr_input_pending - Check if input is pending, interrupt mode | |
199 | * | |
200 | */ | |
201 | static int snt_intr_input_pending(void) | |
202 | { | |
203 | return ia64_sn_console_intr_status() & SAL_CONSOLE_INTR_RECV; | |
204 | } | |
205 | ||
206 | /* these functions are polled and interrupt */ | |
207 | ||
208 | /** | |
209 | * snt_hw_puts_raw - Send raw string to the console, polled or interrupt mode | |
210 | * @s: String | |
211 | * @len: Length | |
212 | * | |
213 | */ | |
214 | static int snt_hw_puts_raw(const char *s, int len) | |
215 | { | |
216 | /* this will call the PROM and not return until this is done */ | |
217 | return ia64_sn_console_putb(s, len); | |
218 | } | |
219 | ||
220 | /** | |
221 | * snt_hw_puts_buffered - Send string to console, polled or interrupt mode | |
222 | * @s: String | |
223 | * @len: Length | |
224 | * | |
225 | */ | |
226 | static int snt_hw_puts_buffered(const char *s, int len) | |
227 | { | |
228 | /* queue data to the PROM */ | |
229 | return ia64_sn_console_xmit_chars((char *)s, len); | |
230 | } | |
231 | ||
232 | /* uart interface structs | |
233 | * These functions are associated with the uart_port that the serial core | |
234 | * infrastructure calls. | |
235 | * | |
236 | * Note: Due to how the console works, many routines are no-ops. | |
237 | */ | |
238 | ||
239 | /** | |
240 | * snp_type - What type of console are we? | |
241 | * @port: Port to operate with (we ignore since we only have one port) | |
242 | * | |
243 | */ | |
244 | static const char *snp_type(struct uart_port *port) | |
245 | { | |
246 | return ("SGI SN L1"); | |
247 | } | |
248 | ||
249 | /** | |
250 | * snp_tx_empty - Is the transmitter empty? We pretend we're always empty | |
251 | * @port: Port to operate on (we ignore since we only have one port) | |
252 | * | |
253 | */ | |
254 | static unsigned int snp_tx_empty(struct uart_port *port) | |
255 | { | |
256 | return 1; | |
257 | } | |
258 | ||
259 | /** | |
260 | * snp_stop_tx - stop the transmitter - no-op for us | |
261 | * @port: Port to operat eon - we ignore - no-op function | |
1da177e4 LT |
262 | * |
263 | */ | |
b129a8cc | 264 | static void snp_stop_tx(struct uart_port *port) |
1da177e4 LT |
265 | { |
266 | } | |
267 | ||
268 | /** | |
269 | * snp_release_port - Free i/o and resources for port - no-op for us | |
270 | * @port: Port to operate on - we ignore - no-op function | |
271 | * | |
272 | */ | |
273 | static void snp_release_port(struct uart_port *port) | |
274 | { | |
275 | } | |
276 | ||
1da177e4 LT |
277 | /** |
278 | * snp_shutdown - shut down the port - free irq and disable - no-op for us | |
279 | * @port: Port to shut down - we ignore | |
280 | * | |
281 | */ | |
282 | static void snp_shutdown(struct uart_port *port) | |
283 | { | |
284 | } | |
285 | ||
286 | /** | |
287 | * snp_set_mctrl - set control lines (dtr, rts, etc) - no-op for our console | |
288 | * @port: Port to operate on - we ignore | |
289 | * @mctrl: Lines to set/unset - we ignore | |
290 | * | |
291 | */ | |
292 | static void snp_set_mctrl(struct uart_port *port, unsigned int mctrl) | |
293 | { | |
294 | } | |
295 | ||
296 | /** | |
297 | * snp_get_mctrl - get contorl line info, we just return a static value | |
298 | * @port: port to operate on - we only have one port so we ignore this | |
299 | * | |
300 | */ | |
301 | static unsigned int snp_get_mctrl(struct uart_port *port) | |
302 | { | |
303 | return TIOCM_CAR | TIOCM_RNG | TIOCM_DSR | TIOCM_CTS; | |
304 | } | |
305 | ||
306 | /** | |
307 | * snp_stop_rx - Stop the receiver - we ignor ethis | |
308 | * @port: Port to operate on - we ignore | |
309 | * | |
310 | */ | |
311 | static void snp_stop_rx(struct uart_port *port) | |
312 | { | |
313 | } | |
314 | ||
315 | /** | |
316 | * snp_start_tx - Start transmitter | |
317 | * @port: Port to operate on | |
1da177e4 LT |
318 | * |
319 | */ | |
b129a8cc | 320 | static void snp_start_tx(struct uart_port *port) |
1da177e4 LT |
321 | { |
322 | if (sal_console_port.sc_ops->sal_wakeup_transmit) | |
323 | sal_console_port.sc_ops->sal_wakeup_transmit(&sal_console_port, | |
324 | TRANSMIT_BUFFERED); | |
325 | ||
326 | } | |
327 | ||
328 | /** | |
329 | * snp_break_ctl - handle breaks - ignored by us | |
330 | * @port: Port to operate on | |
331 | * @break_state: Break state | |
332 | * | |
333 | */ | |
334 | static void snp_break_ctl(struct uart_port *port, int break_state) | |
335 | { | |
336 | } | |
337 | ||
338 | /** | |
339 | * snp_startup - Start up the serial port - always return 0 (We're always on) | |
340 | * @port: Port to operate on | |
341 | * | |
342 | */ | |
343 | static int snp_startup(struct uart_port *port) | |
344 | { | |
345 | return 0; | |
346 | } | |
347 | ||
348 | /** | |
349 | * snp_set_termios - set termios stuff - we ignore these | |
350 | * @port: port to operate on | |
351 | * @termios: New settings | |
352 | * @termios: Old | |
353 | * | |
354 | */ | |
355 | static void | |
606d099c AC |
356 | snp_set_termios(struct uart_port *port, struct ktermios *termios, |
357 | struct ktermios *old) | |
1da177e4 LT |
358 | { |
359 | } | |
360 | ||
361 | /** | |
362 | * snp_request_port - allocate resources for port - ignored by us | |
363 | * @port: port to operate on | |
364 | * | |
365 | */ | |
366 | static int snp_request_port(struct uart_port *port) | |
367 | { | |
368 | return 0; | |
369 | } | |
370 | ||
371 | /** | |
372 | * snp_config_port - allocate resources, set up - we ignore, we're always on | |
373 | * @port: Port to operate on | |
374 | * @flags: flags used for port setup | |
375 | * | |
376 | */ | |
377 | static void snp_config_port(struct uart_port *port, int flags) | |
378 | { | |
379 | } | |
380 | ||
381 | /* Associate the uart functions above - given to serial core */ | |
382 | ||
383 | static struct uart_ops sn_console_ops = { | |
384 | .tx_empty = snp_tx_empty, | |
385 | .set_mctrl = snp_set_mctrl, | |
386 | .get_mctrl = snp_get_mctrl, | |
387 | .stop_tx = snp_stop_tx, | |
388 | .start_tx = snp_start_tx, | |
389 | .stop_rx = snp_stop_rx, | |
1da177e4 LT |
390 | .break_ctl = snp_break_ctl, |
391 | .startup = snp_startup, | |
392 | .shutdown = snp_shutdown, | |
393 | .set_termios = snp_set_termios, | |
394 | .pm = NULL, | |
395 | .type = snp_type, | |
396 | .release_port = snp_release_port, | |
397 | .request_port = snp_request_port, | |
398 | .config_port = snp_config_port, | |
399 | .verify_port = NULL, | |
400 | }; | |
401 | ||
402 | /* End of uart struct functions and defines */ | |
403 | ||
404 | #ifdef DEBUG | |
405 | ||
406 | /** | |
407 | * sn_debug_printf - close to hardware debugging printf | |
408 | * @fmt: printf format | |
409 | * | |
410 | * This is as "close to the metal" as we can get, used when the driver | |
411 | * itself may be broken. | |
412 | * | |
413 | */ | |
414 | static int sn_debug_printf(const char *fmt, ...) | |
415 | { | |
416 | static char printk_buf[1024]; | |
417 | int printed_len; | |
418 | va_list args; | |
419 | ||
420 | va_start(args, fmt); | |
421 | printed_len = vsnprintf(printk_buf, sizeof(printk_buf), fmt, args); | |
422 | ||
423 | if (!sal_console_port.sc_ops) { | |
424 | sal_console_port.sc_ops = &poll_ops; | |
425 | early_sn_setup(); | |
426 | } | |
427 | sal_console_port.sc_ops->sal_puts_raw(printk_buf, printed_len); | |
428 | ||
429 | va_end(args); | |
430 | return printed_len; | |
431 | } | |
432 | #endif /* DEBUG */ | |
433 | ||
434 | /* | |
435 | * Interrupt handling routines. | |
436 | */ | |
437 | ||
438 | /** | |
439 | * sn_receive_chars - Grab characters, pass them to tty layer | |
440 | * @port: Port to operate on | |
1da177e4 LT |
441 | * @flags: irq flags |
442 | * | |
443 | * Note: If we're not registered with the serial core infrastructure yet, | |
444 | * we don't try to send characters to it... | |
445 | * | |
446 | */ | |
447 | static void | |
7d12e780 | 448 | sn_receive_chars(struct sn_cons_port *port, unsigned long flags) |
1da177e4 | 449 | { |
92a19f9c | 450 | struct tty_port *tport = NULL; |
1da177e4 | 451 | int ch; |
1da177e4 LT |
452 | |
453 | if (!port) { | |
90af6d20 | 454 | printk(KERN_ERR "sn_receive_chars - port NULL so can't receive\n"); |
1da177e4 LT |
455 | return; |
456 | } | |
457 | ||
458 | if (!port->sc_ops) { | |
90af6d20 | 459 | printk(KERN_ERR "sn_receive_chars - port->sc_ops NULL so can't receive\n"); |
1da177e4 LT |
460 | return; |
461 | } | |
462 | ||
ebd2c8f6 | 463 | if (port->sc_port.state) { |
421f91d2 | 464 | /* The serial_core stuffs are initialized, use them */ |
92a19f9c | 465 | tport = &port->sc_port.state->port; |
1da177e4 LT |
466 | } |
467 | ||
468 | while (port->sc_ops->sal_input_pending()) { | |
469 | ch = port->sc_ops->sal_getc(); | |
470 | if (ch < 0) { | |
25985edc | 471 | printk(KERN_ERR "sn_console: An error occurred while " |
1da177e4 LT |
472 | "obtaining data from the console (0x%0x)\n", ch); |
473 | break; | |
474 | } | |
475 | #ifdef CONFIG_MAGIC_SYSRQ | |
476 | if (sysrq_requested) { | |
477 | unsigned long sysrq_timeout = sysrq_requested + HZ*5; | |
478 | ||
479 | sysrq_requested = 0; | |
480 | if (ch && time_before(jiffies, sysrq_timeout)) { | |
481 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
f335397d | 482 | handle_sysrq(ch); |
1da177e4 LT |
483 | spin_lock_irqsave(&port->sc_port.lock, flags); |
484 | /* ignore actual sysrq command char */ | |
485 | continue; | |
486 | } | |
487 | } | |
488 | if (ch == *sysrq_serial_ptr) { | |
489 | if (!(*++sysrq_serial_ptr)) { | |
490 | sysrq_requested = jiffies; | |
491 | sysrq_serial_ptr = sysrq_serial_str; | |
492 | } | |
493 | /* | |
494 | * ignore the whole sysrq string except for the | |
495 | * leading escape | |
496 | */ | |
497 | if (ch != '\e') | |
498 | continue; | |
499 | } | |
500 | else | |
501 | sysrq_serial_ptr = sysrq_serial_str; | |
502 | #endif /* CONFIG_MAGIC_SYSRQ */ | |
503 | ||
504 | /* record the character to pass up to the tty layer */ | |
2e124b4a | 505 | if (tport) { |
92a19f9c | 506 | if (tty_insert_flip_char(tport, ch, TTY_NORMAL) == 0) |
1da177e4 LT |
507 | break; |
508 | } | |
509 | port->sc_port.icount.rx++; | |
510 | } | |
511 | ||
2e124b4a JS |
512 | if (tport) |
513 | tty_flip_buffer_push(tport); | |
1da177e4 LT |
514 | } |
515 | ||
516 | /** | |
517 | * sn_transmit_chars - grab characters from serial core, send off | |
518 | * @port: Port to operate on | |
519 | * @raw: Transmit raw or buffered | |
520 | * | |
521 | * Note: If we're early, before we're registered with serial core, the | |
522 | * writes are going through sn_sal_console_write because that's how | |
523 | * register_console has been set up. We currently could have asynch | |
524 | * polls calling this function due to sn_sal_switch_to_asynch but we can | |
525 | * ignore them until we register with the serial core stuffs. | |
526 | * | |
527 | */ | |
528 | static void sn_transmit_chars(struct sn_cons_port *port, int raw) | |
529 | { | |
530 | int xmit_count, tail, head, loops, ii; | |
531 | int result; | |
532 | char *start; | |
533 | struct circ_buf *xmit; | |
534 | ||
535 | if (!port) | |
536 | return; | |
537 | ||
538 | BUG_ON(!port->sc_is_asynch); | |
539 | ||
ebd2c8f6 | 540 | if (port->sc_port.state) { |
421f91d2 | 541 | /* We're initialized, using serial core infrastructure */ |
ebd2c8f6 | 542 | xmit = &port->sc_port.state->xmit; |
1da177e4 LT |
543 | } else { |
544 | /* Probably sn_sal_switch_to_asynch has been run but serial core isn't | |
421f91d2 | 545 | * initialized yet. Just return. Writes are going through |
1da177e4 LT |
546 | * sn_sal_console_write (due to register_console) at this time. |
547 | */ | |
548 | return; | |
549 | } | |
550 | ||
551 | if (uart_circ_empty(xmit) || uart_tx_stopped(&port->sc_port)) { | |
552 | /* Nothing to do. */ | |
328007b7 | 553 | ia64_sn_console_intr_disable(SAL_CONSOLE_INTR_XMIT); |
1da177e4 LT |
554 | return; |
555 | } | |
556 | ||
557 | head = xmit->head; | |
558 | tail = xmit->tail; | |
559 | start = &xmit->buf[tail]; | |
560 | ||
561 | /* twice around gets the tail to the end of the buffer and | |
562 | * then to the head, if needed */ | |
563 | loops = (head < tail) ? 2 : 1; | |
564 | ||
565 | for (ii = 0; ii < loops; ii++) { | |
566 | xmit_count = (head < tail) ? | |
567 | (UART_XMIT_SIZE - tail) : (head - tail); | |
568 | ||
569 | if (xmit_count > 0) { | |
570 | if (raw == TRANSMIT_RAW) | |
571 | result = | |
572 | port->sc_ops->sal_puts_raw(start, | |
573 | xmit_count); | |
574 | else | |
575 | result = | |
576 | port->sc_ops->sal_puts(start, xmit_count); | |
577 | #ifdef DEBUG | |
578 | if (!result) | |
579 | DPRINTF("`"); | |
580 | #endif | |
581 | if (result > 0) { | |
582 | xmit_count -= result; | |
583 | port->sc_port.icount.tx += result; | |
584 | tail += result; | |
585 | tail &= UART_XMIT_SIZE - 1; | |
586 | xmit->tail = tail; | |
587 | start = &xmit->buf[tail]; | |
588 | } | |
589 | } | |
590 | } | |
591 | ||
592 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) | |
593 | uart_write_wakeup(&port->sc_port); | |
594 | ||
595 | if (uart_circ_empty(xmit)) | |
b129a8cc | 596 | snp_stop_tx(&port->sc_port); /* no-op for us */ |
1da177e4 LT |
597 | } |
598 | ||
599 | /** | |
600 | * sn_sal_interrupt - Handle console interrupts | |
601 | * @irq: irq #, useful for debug statements | |
602 | * @dev_id: our pointer to our port (sn_cons_port which contains the uart port) | |
1da177e4 LT |
603 | * |
604 | */ | |
7d12e780 | 605 | static irqreturn_t sn_sal_interrupt(int irq, void *dev_id) |
1da177e4 LT |
606 | { |
607 | struct sn_cons_port *port = (struct sn_cons_port *)dev_id; | |
608 | unsigned long flags; | |
609 | int status = ia64_sn_console_intr_status(); | |
610 | ||
611 | if (!port) | |
612 | return IRQ_NONE; | |
613 | ||
614 | spin_lock_irqsave(&port->sc_port.lock, flags); | |
615 | if (status & SAL_CONSOLE_INTR_RECV) { | |
7d12e780 | 616 | sn_receive_chars(port, flags); |
1da177e4 LT |
617 | } |
618 | if (status & SAL_CONSOLE_INTR_XMIT) { | |
619 | sn_transmit_chars(port, TRANSMIT_BUFFERED); | |
620 | } | |
621 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
622 | return IRQ_HANDLED; | |
623 | } | |
624 | ||
1da177e4 LT |
625 | /** |
626 | * sn_sal_timer_poll - this function handles polled console mode | |
627 | * @data: A pointer to our sn_cons_port (which contains the uart port) | |
628 | * | |
629 | * data is the pointer that init_timer will store for us. This function is | |
630 | * associated with init_timer to see if there is any console traffic. | |
631 | * Obviously not used in interrupt mode | |
632 | * | |
633 | */ | |
634 | static void sn_sal_timer_poll(unsigned long data) | |
635 | { | |
636 | struct sn_cons_port *port = (struct sn_cons_port *)data; | |
637 | unsigned long flags; | |
638 | ||
639 | if (!port) | |
640 | return; | |
641 | ||
642 | if (!port->sc_port.irq) { | |
643 | spin_lock_irqsave(&port->sc_port.lock, flags); | |
644 | if (sn_process_input) | |
8c1addbc | 645 | sn_receive_chars(port, flags); |
1da177e4 LT |
646 | sn_transmit_chars(port, TRANSMIT_RAW); |
647 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
648 | mod_timer(&port->sc_timer, | |
649 | jiffies + port->sc_interrupt_timeout); | |
650 | } | |
651 | } | |
652 | ||
653 | /* | |
654 | * Boot-time initialization code | |
655 | */ | |
656 | ||
657 | /** | |
658 | * sn_sal_switch_to_asynch - Switch to async mode (as opposed to synch) | |
659 | * @port: Our sn_cons_port (which contains the uart port) | |
660 | * | |
661 | * So this is used by sn_sal_serial_console_init (early on, before we're | |
4e62794b | 662 | * registered with serial core). It's also used by sn_sal_init |
1da177e4 LT |
663 | * right after we've registered with serial core. The later only happens |
664 | * if we didn't already come through here via sn_sal_serial_console_init. | |
665 | * | |
666 | */ | |
667 | static void __init sn_sal_switch_to_asynch(struct sn_cons_port *port) | |
668 | { | |
669 | unsigned long flags; | |
670 | ||
671 | if (!port) | |
672 | return; | |
673 | ||
674 | DPRINTF("sn_console: about to switch to asynchronous console\n"); | |
675 | ||
676 | /* without early_printk, we may be invoked late enough to race | |
677 | * with other cpus doing console IO at this point, however | |
678 | * console interrupts will never be enabled */ | |
679 | spin_lock_irqsave(&port->sc_port.lock, flags); | |
680 | ||
681 | /* early_printk invocation may have done this for us */ | |
682 | if (!port->sc_ops) | |
683 | port->sc_ops = &poll_ops; | |
684 | ||
685 | /* we can't turn on the console interrupt (as request_irq | |
686 | * calls kmalloc, which isn't set up yet), so we rely on a | |
687 | * timer to poll for input and push data from the console | |
688 | * buffer. | |
689 | */ | |
690 | init_timer(&port->sc_timer); | |
691 | port->sc_timer.function = sn_sal_timer_poll; | |
692 | port->sc_timer.data = (unsigned long)port; | |
693 | ||
694 | if (IS_RUNNING_ON_SIMULATOR()) | |
695 | port->sc_interrupt_timeout = 6; | |
696 | else { | |
697 | /* 960cps / 16 char FIFO = 60HZ | |
698 | * HZ / (SN_SAL_FIFO_SPEED_CPS / SN_SAL_FIFO_DEPTH) */ | |
699 | port->sc_interrupt_timeout = | |
700 | HZ * SN_SAL_UART_FIFO_DEPTH / SN_SAL_UART_FIFO_SPEED_CPS; | |
701 | } | |
702 | mod_timer(&port->sc_timer, jiffies + port->sc_interrupt_timeout); | |
703 | ||
704 | port->sc_is_asynch = 1; | |
705 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
706 | } | |
707 | ||
708 | /** | |
709 | * sn_sal_switch_to_interrupts - Switch to interrupt driven mode | |
710 | * @port: Our sn_cons_port (which contains the uart port) | |
711 | * | |
4e62794b | 712 | * In sn_sal_init, after we're registered with serial core and |
1da177e4 LT |
713 | * the port is added, this function is called to switch us to interrupt |
714 | * mode. We were previously in asynch/polling mode (using init_timer). | |
715 | * | |
716 | * We attempt to switch to interrupt mode here by calling | |
f70c81d4 | 717 | * request_irq. If that works out, we enable receive interrupts. |
1da177e4 LT |
718 | */ |
719 | static void __init sn_sal_switch_to_interrupts(struct sn_cons_port *port) | |
720 | { | |
1da177e4 LT |
721 | unsigned long flags; |
722 | ||
f70c81d4 PG |
723 | if (port) { |
724 | DPRINTF("sn_console: switching to interrupt driven console\n"); | |
1da177e4 | 725 | |
f70c81d4 | 726 | if (request_irq(SGI_UART_VECTOR, sn_sal_interrupt, |
9cfb5c05 | 727 | IRQF_SHARED, |
f70c81d4 PG |
728 | "SAL console driver", port) >= 0) { |
729 | spin_lock_irqsave(&port->sc_port.lock, flags); | |
730 | port->sc_port.irq = SGI_UART_VECTOR; | |
731 | port->sc_ops = &intr_ops; | |
48e30fa0 | 732 | irq_set_handler(port->sc_port.irq, handle_level_irq); |
1da177e4 | 733 | |
f70c81d4 PG |
734 | /* turn on receive interrupts */ |
735 | ia64_sn_console_intr_enable(SAL_CONSOLE_INTR_RECV); | |
736 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
737 | } | |
738 | else { | |
739 | printk(KERN_INFO | |
740 | "sn_console: console proceeding in polled mode\n"); | |
741 | } | |
1da177e4 | 742 | } |
1da177e4 LT |
743 | } |
744 | ||
745 | /* | |
746 | * Kernel console definitions | |
747 | */ | |
748 | ||
749 | static void sn_sal_console_write(struct console *, const char *, unsigned); | |
17e0c7cc | 750 | static int sn_sal_console_setup(struct console *, char *); |
434498d5 | 751 | static struct uart_driver sal_console_uart; |
1da177e4 LT |
752 | extern struct tty_driver *uart_console_device(struct console *, int *); |
753 | ||
754 | static struct console sal_console = { | |
755 | .name = DEVICE_NAME, | |
756 | .write = sn_sal_console_write, | |
757 | .device = uart_console_device, | |
758 | .setup = sn_sal_console_setup, | |
759 | .index = -1, /* unspecified */ | |
760 | .data = &sal_console_uart, | |
761 | }; | |
762 | ||
763 | #define SAL_CONSOLE &sal_console | |
764 | ||
434498d5 | 765 | static struct uart_driver sal_console_uart = { |
1da177e4 LT |
766 | .owner = THIS_MODULE, |
767 | .driver_name = "sn_console", | |
768 | .dev_name = DEVICE_NAME, | |
769 | .major = 0, /* major/minor set at registration time per USE_DYNAMIC_MINOR */ | |
770 | .minor = 0, | |
771 | .nr = 1, /* one port */ | |
772 | .cons = SAL_CONSOLE, | |
773 | }; | |
774 | ||
775 | /** | |
4e62794b | 776 | * sn_sal_init - When the kernel loads us, get us rolling w/ serial core |
1da177e4 LT |
777 | * |
778 | * Before this is called, we've been printing kernel messages in a special | |
779 | * early mode not making use of the serial core infrastructure. When our | |
780 | * driver is loaded for real, we register the driver and port with serial | |
781 | * core and try to enable interrupt driven mode. | |
782 | * | |
783 | */ | |
4e62794b | 784 | static int __init sn_sal_init(void) |
1da177e4 LT |
785 | { |
786 | int retval; | |
787 | ||
788 | if (!ia64_platform_is("sn2")) | |
f032f908 | 789 | return 0; |
1da177e4 LT |
790 | |
791 | printk(KERN_INFO "sn_console: Console driver init\n"); | |
792 | ||
793 | if (USE_DYNAMIC_MINOR == 1) { | |
794 | misc.minor = MISC_DYNAMIC_MINOR; | |
795 | misc.name = DEVICE_NAME_DYNAMIC; | |
796 | retval = misc_register(&misc); | |
797 | if (retval != 0) { | |
d171e519 JS |
798 | printk(KERN_WARNING "Failed to register console " |
799 | "device using misc_register.\n"); | |
1da177e4 LT |
800 | return -ENODEV; |
801 | } | |
802 | sal_console_uart.major = MISC_MAJOR; | |
803 | sal_console_uart.minor = misc.minor; | |
804 | } else { | |
805 | sal_console_uart.major = DEVICE_MAJOR; | |
806 | sal_console_uart.minor = DEVICE_MINOR; | |
807 | } | |
808 | ||
809 | /* We register the driver and the port before switching to interrupts | |
810 | * or async above so the proper uart structures are populated */ | |
811 | ||
812 | if (uart_register_driver(&sal_console_uart) < 0) { | |
813 | printk | |
4e62794b | 814 | ("ERROR sn_sal_init failed uart_register_driver, line %d\n", |
1da177e4 LT |
815 | __LINE__); |
816 | return -ENODEV; | |
817 | } | |
818 | ||
819 | spin_lock_init(&sal_console_port.sc_port.lock); | |
820 | ||
821 | /* Setup the port struct with the minimum needed */ | |
822 | sal_console_port.sc_port.membase = (char *)1; /* just needs to be non-zero */ | |
823 | sal_console_port.sc_port.type = PORT_16550A; | |
824 | sal_console_port.sc_port.fifosize = SN_SAL_MAX_CHARS; | |
825 | sal_console_port.sc_port.ops = &sn_console_ops; | |
826 | sal_console_port.sc_port.line = 0; | |
827 | ||
828 | if (uart_add_one_port(&sal_console_uart, &sal_console_port.sc_port) < 0) { | |
829 | /* error - not sure what I'd do - so I'll do nothing */ | |
71cc2c21 | 830 | printk(KERN_ERR "%s: unable to add port\n", __func__); |
1da177e4 LT |
831 | } |
832 | ||
833 | /* when this driver is compiled in, the console initialization | |
834 | * will have already switched us into asynchronous operation | |
4e62794b | 835 | * before we get here through the initcalls */ |
1da177e4 LT |
836 | if (!sal_console_port.sc_is_asynch) { |
837 | sn_sal_switch_to_asynch(&sal_console_port); | |
838 | } | |
839 | ||
4e62794b | 840 | /* at this point (device_init) we can try to turn on interrupts */ |
1da177e4 LT |
841 | if (!IS_RUNNING_ON_SIMULATOR()) { |
842 | sn_sal_switch_to_interrupts(&sal_console_port); | |
843 | } | |
844 | sn_process_input = 1; | |
845 | return 0; | |
846 | } | |
4e62794b | 847 | device_initcall(sn_sal_init); |
1da177e4 LT |
848 | |
849 | /** | |
850 | * puts_raw_fixed - sn_sal_console_write helper for adding \r's as required | |
851 | * @puts_raw : puts function to do the writing | |
852 | * @s: input string | |
853 | * @count: length | |
854 | * | |
855 | * We need a \r ahead of every \n for direct writes through | |
856 | * ia64_sn_console_putb (what sal_puts_raw below actually does). | |
857 | * | |
858 | */ | |
859 | ||
860 | static void puts_raw_fixed(int (*puts_raw) (const char *s, int len), | |
861 | const char *s, int count) | |
862 | { | |
863 | const char *s1; | |
864 | ||
865 | /* Output '\r' before each '\n' */ | |
866 | while ((s1 = memchr(s, '\n', count)) != NULL) { | |
867 | puts_raw(s, s1 - s); | |
868 | puts_raw("\r\n", 2); | |
869 | count -= s1 + 1 - s; | |
870 | s = s1 + 1; | |
871 | } | |
872 | puts_raw(s, count); | |
873 | } | |
874 | ||
875 | /** | |
876 | * sn_sal_console_write - Print statements before serial core available | |
877 | * @console: Console to operate on - we ignore since we have just one | |
878 | * @s: String to send | |
879 | * @count: length | |
880 | * | |
881 | * This is referenced in the console struct. It is used for early | |
882 | * console printing before we register with serial core and for things | |
883 | * such as kdb. The console_lock must be held when we get here. | |
884 | * | |
885 | * This function has some code for trying to print output even if the lock | |
886 | * is held. We try to cover the case where a lock holder could have died. | |
887 | * We don't use this special case code if we're not registered with serial | |
888 | * core yet. After we're registered with serial core, the only time this | |
889 | * function would be used is for high level kernel output like magic sys req, | |
890 | * kdb, and printk's. | |
891 | */ | |
892 | static void | |
893 | sn_sal_console_write(struct console *co, const char *s, unsigned count) | |
894 | { | |
895 | unsigned long flags = 0; | |
896 | struct sn_cons_port *port = &sal_console_port; | |
1da177e4 | 897 | static int stole_lock = 0; |
1da177e4 LT |
898 | |
899 | BUG_ON(!port->sc_is_asynch); | |
900 | ||
901 | /* We can't look at the xmit buffer if we're not registered with serial core | |
902 | * yet. So only do the fancy recovery after registering | |
903 | */ | |
ebd2c8f6 | 904 | if (!port->sc_port.state) { |
d171e519 JS |
905 | /* Not yet registered with serial core - simple case */ |
906 | puts_raw_fixed(port->sc_ops->sal_puts_raw, s, count); | |
907 | return; | |
908 | } | |
1da177e4 | 909 | |
d171e519 JS |
910 | /* somebody really wants this output, might be an |
911 | * oops, kdb, panic, etc. make sure they get it. */ | |
912 | if (spin_is_locked(&port->sc_port.lock)) { | |
ebd2c8f6 AC |
913 | int lhead = port->sc_port.state->xmit.head; |
914 | int ltail = port->sc_port.state->xmit.tail; | |
d171e519 JS |
915 | int counter, got_lock = 0; |
916 | ||
917 | /* | |
918 | * We attempt to determine if someone has died with the | |
919 | * lock. We wait ~20 secs after the head and tail ptrs | |
920 | * stop moving and assume the lock holder is not functional | |
921 | * and plow ahead. If the lock is freed within the time out | |
922 | * period we re-get the lock and go ahead normally. We also | |
923 | * remember if we have plowed ahead so that we don't have | |
924 | * to wait out the time out period again - the asumption | |
925 | * is that we will time out again. | |
926 | */ | |
1da177e4 | 927 | |
d171e519 JS |
928 | for (counter = 0; counter < 150; mdelay(125), counter++) { |
929 | if (!spin_is_locked(&port->sc_port.lock) | |
930 | || stole_lock) { | |
931 | if (!stole_lock) { | |
932 | spin_lock_irqsave(&port->sc_port.lock, | |
933 | flags); | |
934 | got_lock = 1; | |
1da177e4 | 935 | } |
d171e519 | 936 | break; |
1da177e4 | 937 | } else { |
d171e519 | 938 | /* still locked */ |
ebd2c8f6 | 939 | if ((lhead != port->sc_port.state->xmit.head) |
d171e519 | 940 | || (ltail != |
ebd2c8f6 | 941 | port->sc_port.state->xmit.tail)) { |
d171e519 | 942 | lhead = |
ebd2c8f6 | 943 | port->sc_port.state->xmit.head; |
d171e519 | 944 | ltail = |
ebd2c8f6 | 945 | port->sc_port.state->xmit.tail; |
d171e519 JS |
946 | counter = 0; |
947 | } | |
1da177e4 | 948 | } |
d171e519 JS |
949 | } |
950 | /* flush anything in the serial core xmit buffer, raw */ | |
951 | sn_transmit_chars(port, 1); | |
952 | if (got_lock) { | |
1da177e4 | 953 | spin_unlock_irqrestore(&port->sc_port.lock, flags); |
d171e519 JS |
954 | stole_lock = 0; |
955 | } else { | |
956 | /* fell thru */ | |
957 | stole_lock = 1; | |
1da177e4 | 958 | } |
d171e519 JS |
959 | puts_raw_fixed(port->sc_ops->sal_puts_raw, s, count); |
960 | } else { | |
961 | stole_lock = 0; | |
962 | spin_lock_irqsave(&port->sc_port.lock, flags); | |
963 | sn_transmit_chars(port, 1); | |
964 | spin_unlock_irqrestore(&port->sc_port.lock, flags); | |
965 | ||
1da177e4 LT |
966 | puts_raw_fixed(port->sc_ops->sal_puts_raw, s, count); |
967 | } | |
968 | } | |
969 | ||
970 | ||
971 | /** | |
972 | * sn_sal_console_setup - Set up console for early printing | |
973 | * @co: Console to work with | |
974 | * @options: Options to set | |
975 | * | |
976 | * Altix console doesn't do anything with baud rates, etc, anyway. | |
977 | * | |
978 | * This isn't required since not providing the setup function in the | |
979 | * console struct is ok. However, other patches like KDB plop something | |
980 | * here so providing it is easier. | |
981 | * | |
982 | */ | |
17e0c7cc | 983 | static int sn_sal_console_setup(struct console *co, char *options) |
1da177e4 LT |
984 | { |
985 | return 0; | |
986 | } | |
987 | ||
988 | /** | |
989 | * sn_sal_console_write_early - simple early output routine | |
990 | * @co - console struct | |
991 | * @s - string to print | |
992 | * @count - count | |
993 | * | |
994 | * Simple function to provide early output, before even | |
995 | * sn_sal_serial_console_init is called. Referenced in the | |
996 | * console struct registerd in sn_serial_console_early_setup. | |
997 | * | |
998 | */ | |
999 | static void __init | |
1000 | sn_sal_console_write_early(struct console *co, const char *s, unsigned count) | |
1001 | { | |
1002 | puts_raw_fixed(sal_console_port.sc_ops->sal_puts_raw, s, count); | |
1003 | } | |
1004 | ||
1005 | /* Used for very early console printing - again, before | |
1006 | * sn_sal_serial_console_init is run */ | |
1007 | static struct console sal_console_early __initdata = { | |
1008 | .name = "sn_sal", | |
1009 | .write = sn_sal_console_write_early, | |
1010 | .flags = CON_PRINTBUFFER, | |
1011 | .index = -1, | |
1012 | }; | |
1013 | ||
1014 | /** | |
1015 | * sn_serial_console_early_setup - Sets up early console output support | |
1016 | * | |
1017 | * Register a console early on... This is for output before even | |
1018 | * sn_sal_serial_cosnole_init is called. This function is called from | |
1019 | * setup.c. This allows us to do really early polled writes. When | |
1020 | * sn_sal_serial_console_init is called, this console is unregistered | |
1021 | * and a new one registered. | |
1022 | */ | |
1023 | int __init sn_serial_console_early_setup(void) | |
1024 | { | |
1025 | if (!ia64_platform_is("sn2")) | |
1026 | return -1; | |
1027 | ||
1028 | sal_console_port.sc_ops = &poll_ops; | |
71841b8f | 1029 | spin_lock_init(&sal_console_port.sc_port.lock); |
1da177e4 LT |
1030 | early_sn_setup(); /* Find SAL entry points */ |
1031 | register_console(&sal_console_early); | |
1032 | ||
1033 | return 0; | |
1034 | } | |
1035 | ||
1036 | /** | |
1037 | * sn_sal_serial_console_init - Early console output - set up for register | |
1038 | * | |
1039 | * This function is called when regular console init happens. Because we | |
1040 | * support even earlier console output with sn_serial_console_early_setup | |
1041 | * (called from setup.c directly), this function unregisters the really | |
1042 | * early console. | |
1043 | * | |
1044 | * Note: Even if setup.c doesn't register sal_console_early, unregistering | |
1045 | * it here doesn't hurt anything. | |
1046 | * | |
1047 | */ | |
1048 | static int __init sn_sal_serial_console_init(void) | |
1049 | { | |
1050 | if (ia64_platform_is("sn2")) { | |
1051 | sn_sal_switch_to_asynch(&sal_console_port); | |
1052 | DPRINTF("sn_sal_serial_console_init : register console\n"); | |
1053 | register_console(&sal_console); | |
1054 | unregister_console(&sal_console_early); | |
1055 | } | |
1056 | return 0; | |
1057 | } | |
1058 | ||
1059 | console_initcall(sn_sal_serial_console_init); |