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MIPS: Yosemite, Emma: Fix off-by-two in arcs_cmdline buffer size check
[linux-2.6/linux-mips.git] / drivers / tty / serial / sb1250-duart.c
blob0be8a2f00d0ba92b76c990c8204f23ce4cc0d84d
1 /*
2 * Support for the asynchronous serial interface (DUART) included
3 * in the BCM1250 and derived System-On-a-Chip (SOC) devices.
4 *
5 * Copyright (c) 2007 Maciej W. Rozycki
6 *
7 * Derived from drivers/char/sb1250_duart.c for which the following
8 * copyright applies:
9 *
10 * Copyright (c) 2000, 2001, 2002, 2003, 2004 Broadcom Corporation
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 *
17 * References:
18 *
19 * "BCM1250/BCM1125/BCM1125H User Manual", Broadcom Corporation
20 */
21
22 #if defined(CONFIG_SERIAL_SB1250_DUART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
23 #define SUPPORT_SYSRQ
24 #endif
25
26 #include <linux/compiler.h>
27 #include <linux/console.h>
28 #include <linux/delay.h>
29 #include <linux/errno.h>
30 #include <linux/init.h>
31 #include <linux/interrupt.h>
32 #include <linux/ioport.h>
33 #include <linux/kernel.h>
34 #include <linux/major.h>
35 #include <linux/serial.h>
36 #include <linux/serial_core.h>
37 #include <linux/spinlock.h>
38 #include <linux/sysrq.h>
39 #include <linux/tty.h>
40 #include <linux/tty_flip.h>
41 #include <linux/types.h>
42
43 #include <linux/atomic.h>
44 #include <asm/io.h>
45 #include <asm/war.h>
46
47 #include <asm/sibyte/sb1250.h>
48 #include <asm/sibyte/sb1250_uart.h>
49 #include <asm/sibyte/swarm.h>
50
51
52 #if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
53 #include <asm/sibyte/bcm1480_regs.h>
54 #include <asm/sibyte/bcm1480_int.h>
55
56 #define SBD_CHANREGS(line) A_BCM1480_DUART_CHANREG((line), 0)
57 #define SBD_CTRLREGS(line) A_BCM1480_DUART_CTRLREG((line), 0)
58 #define SBD_INT(line) (K_BCM1480_INT_UART_0 + (line))
59
60 #define DUART_CHANREG_SPACING BCM1480_DUART_CHANREG_SPACING
61
62 #define R_DUART_IMRREG(line) R_BCM1480_DUART_IMRREG(line)
63 #define R_DUART_INCHREG(line) R_BCM1480_DUART_INCHREG(line)
64 #define R_DUART_ISRREG(line) R_BCM1480_DUART_ISRREG(line)
65
66 #elif defined(CONFIG_SIBYTE_SB1250) || defined(CONFIG_SIBYTE_BCM112X)
67 #include <asm/sibyte/sb1250_regs.h>
68 #include <asm/sibyte/sb1250_int.h>
69
70 #define SBD_CHANREGS(line) A_DUART_CHANREG((line), 0)
71 #define SBD_CTRLREGS(line) A_DUART_CTRLREG(0)
72 #define SBD_INT(line) (K_INT_UART_0 + (line))
73
74 #else
75 #error invalid SB1250 UART configuration
76
77 #endif
78
79
80 MODULE_AUTHOR("Maciej W. Rozycki <macro@linux-mips.org>");
81 MODULE_DESCRIPTION("BCM1xxx on-chip DUART serial driver");
82 MODULE_LICENSE("GPL");
83
84
85 #define DUART_MAX_CHIP 2
86 #define DUART_MAX_SIDE 2
87
88 /*
89 * Per-port state.
90 */
91 struct sbd_port {
92 struct sbd_duart *duart;
93 struct uart_port port;
94 unsigned char __iomem *memctrl;
95 int tx_stopped;
96 int initialised;
97 };
98
99 /*
100 * Per-DUART state for the shared register space.
101 */
102 struct sbd_duart {
103 struct sbd_port sport[2];
104 unsigned long mapctrl;
105 atomic_t map_guard;
106 };
107
108 #define to_sport(uport) container_of(uport, struct sbd_port, port)
109
110 static struct sbd_duart sbd_duarts[DUART_MAX_CHIP];
111
112
113 /*
114 * Reading and writing SB1250 DUART registers.
115 *
116 * There are three register spaces: two per-channel ones and
117 * a shared one. We have to define accessors appropriately.
118 * All registers are 64-bit and all but the Baud Rate Clock
119 * registers only define 8 least significant bits. There is
120 * also a workaround to take into account. Raw accessors use
121 * the full register width, but cooked ones truncate it
122 * intentionally so that the rest of the driver does not care.
123 */
124 static u64 __read_sbdchn(struct sbd_port *sport, int reg)
125 {
126 void __iomem *csr = sport->port.membase + reg;
127
128 return __raw_readq(csr);
129 }
130
131 static u64 __read_sbdshr(struct sbd_port *sport, int reg)
132 {
133 void __iomem *csr = sport->memctrl + reg;
134
135 return __raw_readq(csr);
136 }
137
138 static void __write_sbdchn(struct sbd_port *sport, int reg, u64 value)
139 {
140 void __iomem *csr = sport->port.membase + reg;
141
142 __raw_writeq(value, csr);
143 }
144
145 static void __write_sbdshr(struct sbd_port *sport, int reg, u64 value)
146 {
147 void __iomem *csr = sport->memctrl + reg;
148
149 __raw_writeq(value, csr);
150 }
151
152 /*
153 * In bug 1956, we get glitches that can mess up uart registers. This
154 * "read-mode-reg after any register access" is an accepted workaround.
155 */
156 static void __war_sbd1956(struct sbd_port *sport)
157 {
158 __read_sbdchn(sport, R_DUART_MODE_REG_1);
159 __read_sbdchn(sport, R_DUART_MODE_REG_2);
160 }
161
162 static unsigned char read_sbdchn(struct sbd_port *sport, int reg)
163 {
164 unsigned char retval;
165
166 retval = __read_sbdchn(sport, reg);
167 if (SIBYTE_1956_WAR)
168 __war_sbd1956(sport);
169 return retval;
170 }
171
172 static unsigned char read_sbdshr(struct sbd_port *sport, int reg)
173 {
174 unsigned char retval;
175
176 retval = __read_sbdshr(sport, reg);
177 if (SIBYTE_1956_WAR)
178 __war_sbd1956(sport);
179 return retval;
180 }
181
182 static void write_sbdchn(struct sbd_port *sport, int reg, unsigned int value)
183 {
184 __write_sbdchn(sport, reg, value);
185 if (SIBYTE_1956_WAR)
186 __war_sbd1956(sport);
187 }
188
189 static void write_sbdshr(struct sbd_port *sport, int reg, unsigned int value)
190 {
191 __write_sbdshr(sport, reg, value);
192 if (SIBYTE_1956_WAR)
193 __war_sbd1956(sport);
194 }
195
196
197 static int sbd_receive_ready(struct sbd_port *sport)
198 {
199 return read_sbdchn(sport, R_DUART_STATUS) & M_DUART_RX_RDY;
200 }
201
202 static int sbd_receive_drain(struct sbd_port *sport)
203 {
204 int loops = 10000;
205
206 while (sbd_receive_ready(sport) && --loops)
207 read_sbdchn(sport, R_DUART_RX_HOLD);
208 return loops;
209 }
210
211 static int __maybe_unused sbd_transmit_ready(struct sbd_port *sport)
212 {
213 return read_sbdchn(sport, R_DUART_STATUS) & M_DUART_TX_RDY;
214 }
215
216 static int __maybe_unused sbd_transmit_drain(struct sbd_port *sport)
217 {
218 int loops = 10000;
219
220 while (!sbd_transmit_ready(sport) && --loops)
221 udelay(2);
222 return loops;
223 }
224
225 static int sbd_transmit_empty(struct sbd_port *sport)
226 {
227 return read_sbdchn(sport, R_DUART_STATUS) & M_DUART_TX_EMT;
228 }
229
230 static int sbd_line_drain(struct sbd_port *sport)
231 {
232 int loops = 10000;
233
234 while (!sbd_transmit_empty(sport) && --loops)
235 udelay(2);
236 return loops;
237 }
238
239
240 static unsigned int sbd_tx_empty(struct uart_port *uport)
241 {
242 struct sbd_port *sport = to_sport(uport);
243
244 return sbd_transmit_empty(sport) ? TIOCSER_TEMT : 0;
245 }
246
247 static unsigned int sbd_get_mctrl(struct uart_port *uport)
248 {
249 struct sbd_port *sport = to_sport(uport);
250 unsigned int mctrl, status;
251
252 status = read_sbdshr(sport, R_DUART_IN_PORT);
253 status >>= (uport->line) % 2;
254 mctrl = (!(status & M_DUART_IN_PIN0_VAL) ? TIOCM_CTS : 0) |
255 (!(status & M_DUART_IN_PIN4_VAL) ? TIOCM_CAR : 0) |
256 (!(status & M_DUART_RIN0_PIN) ? TIOCM_RNG : 0) |
257 (!(status & M_DUART_IN_PIN2_VAL) ? TIOCM_DSR : 0);
258 return mctrl;
259 }
260
261 static void sbd_set_mctrl(struct uart_port *uport, unsigned int mctrl)
262 {
263 struct sbd_port *sport = to_sport(uport);
264 unsigned int clr = 0, set = 0, mode2;
265
266 if (mctrl & TIOCM_DTR)
267 set |= M_DUART_SET_OPR2;
268 else
269 clr |= M_DUART_CLR_OPR2;
270 if (mctrl & TIOCM_RTS)
271 set |= M_DUART_SET_OPR0;
272 else
273 clr |= M_DUART_CLR_OPR0;
274 clr <<= (uport->line) % 2;
275 set <<= (uport->line) % 2;
276
277 mode2 = read_sbdchn(sport, R_DUART_MODE_REG_2);
278 mode2 &= ~M_DUART_CHAN_MODE;
279 if (mctrl & TIOCM_LOOP)
280 mode2 |= V_DUART_CHAN_MODE_LCL_LOOP;
281 else
282 mode2 |= V_DUART_CHAN_MODE_NORMAL;
283
284 write_sbdshr(sport, R_DUART_CLEAR_OPR, clr);
285 write_sbdshr(sport, R_DUART_SET_OPR, set);
286 write_sbdchn(sport, R_DUART_MODE_REG_2, mode2);
287 }
288
289 static void sbd_stop_tx(struct uart_port *uport)
290 {
291 struct sbd_port *sport = to_sport(uport);
292
293 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS);
294 sport->tx_stopped = 1;
295 };
296
297 static void sbd_start_tx(struct uart_port *uport)
298 {
299 struct sbd_port *sport = to_sport(uport);
300 unsigned int mask;
301
302 /* Enable tx interrupts. */
303 mask = read_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2));
304 mask |= M_DUART_IMR_TX;
305 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), mask);
306
307 /* Go!, go!, go!... */
308 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_EN);
309 sport->tx_stopped = 0;
310 };
311
312 static void sbd_stop_rx(struct uart_port *uport)
313 {
314 struct sbd_port *sport = to_sport(uport);
315
316 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), 0);
317 };
318
319 static void sbd_enable_ms(struct uart_port *uport)
320 {
321 struct sbd_port *sport = to_sport(uport);
322
323 write_sbdchn(sport, R_DUART_AUXCTL_X,
324 M_DUART_CIN_CHNG_ENA | M_DUART_CTS_CHNG_ENA);
325 }
326
327 static void sbd_break_ctl(struct uart_port *uport, int break_state)
328 {
329 struct sbd_port *sport = to_sport(uport);
330
331 if (break_state == -1)
332 write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_START_BREAK);
333 else
334 write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_STOP_BREAK);
335 }
336
337
338 static void sbd_receive_chars(struct sbd_port *sport)
339 {
340 struct uart_port *uport = &sport->port;
341 struct uart_icount *icount;
342 unsigned int status, ch, flag;
343 int count;
344
345 for (count = 16; count; count--) {
346 status = read_sbdchn(sport, R_DUART_STATUS);
347 if (!(status & M_DUART_RX_RDY))
348 break;
349
350 ch = read_sbdchn(sport, R_DUART_RX_HOLD);
351
352 flag = TTY_NORMAL;
353
354 icount = &uport->icount;
355 icount->rx++;
356
357 if (unlikely(status &
358 (M_DUART_RCVD_BRK | M_DUART_FRM_ERR |
359 M_DUART_PARITY_ERR | M_DUART_OVRUN_ERR))) {
360 if (status & M_DUART_RCVD_BRK) {
361 icount->brk++;
362 if (uart_handle_break(uport))
363 continue;
364 } else if (status & M_DUART_FRM_ERR)
365 icount->frame++;
366 else if (status & M_DUART_PARITY_ERR)
367 icount->parity++;
368 if (status & M_DUART_OVRUN_ERR)
369 icount->overrun++;
370
371 status &= uport->read_status_mask;
372 if (status & M_DUART_RCVD_BRK)
373 flag = TTY_BREAK;
374 else if (status & M_DUART_FRM_ERR)
375 flag = TTY_FRAME;
376 else if (status & M_DUART_PARITY_ERR)
377 flag = TTY_PARITY;
378 }
379
380 if (uart_handle_sysrq_char(uport, ch))
381 continue;
382
383 uart_insert_char(uport, status, M_DUART_OVRUN_ERR, ch, flag);
384 }
385
386 tty_flip_buffer_push(uport->state->port.tty);
387 }
388
389 static void sbd_transmit_chars(struct sbd_port *sport)
390 {
391 struct uart_port *uport = &sport->port;
392 struct circ_buf *xmit = &sport->port.state->xmit;
393 unsigned int mask;
394 int stop_tx;
395
396 /* XON/XOFF chars. */
397 if (sport->port.x_char) {
398 write_sbdchn(sport, R_DUART_TX_HOLD, sport->port.x_char);
399 sport->port.icount.tx++;
400 sport->port.x_char = 0;
401 return;
402 }
403
404 /* If nothing to do or stopped or hardware stopped. */
405 stop_tx = (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port));
406
407 /* Send char. */
408 if (!stop_tx) {
409 write_sbdchn(sport, R_DUART_TX_HOLD, xmit->buf[xmit->tail]);
410 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
411 sport->port.icount.tx++;
412
413 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
414 uart_write_wakeup(&sport->port);
415 }
416
417 /* Are we are done? */
418 if (stop_tx || uart_circ_empty(xmit)) {
419 /* Disable tx interrupts. */
420 mask = read_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2));
421 mask &= ~M_DUART_IMR_TX;
422 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), mask);
423 }
424 }
425
426 static void sbd_status_handle(struct sbd_port *sport)
427 {
428 struct uart_port *uport = &sport->port;
429 unsigned int delta;
430
431 delta = read_sbdshr(sport, R_DUART_INCHREG((uport->line) % 2));
432 delta >>= (uport->line) % 2;
433
434 if (delta & (M_DUART_IN_PIN0_VAL << S_DUART_IN_PIN_CHNG))
435 uart_handle_cts_change(uport, !(delta & M_DUART_IN_PIN0_VAL));
436
437 if (delta & (M_DUART_IN_PIN2_VAL << S_DUART_IN_PIN_CHNG))
438 uport->icount.dsr++;
439
440 if (delta & ((M_DUART_IN_PIN2_VAL | M_DUART_IN_PIN0_VAL) <<
441 S_DUART_IN_PIN_CHNG))
442 wake_up_interruptible(&uport->state->port.delta_msr_wait);
443 }
444
445 static irqreturn_t sbd_interrupt(int irq, void *dev_id)
446 {
447 struct sbd_port *sport = dev_id;
448 struct uart_port *uport = &sport->port;
449 irqreturn_t status = IRQ_NONE;
450 unsigned int intstat;
451 int count;
452
453 for (count = 16; count; count--) {
454 intstat = read_sbdshr(sport,
455 R_DUART_ISRREG((uport->line) % 2));
456 intstat &= read_sbdshr(sport,
457 R_DUART_IMRREG((uport->line) % 2));
458 intstat &= M_DUART_ISR_ALL;
459 if (!intstat)
460 break;
461
462 if (intstat & M_DUART_ISR_RX)
463 sbd_receive_chars(sport);
464 if (intstat & M_DUART_ISR_IN)
465 sbd_status_handle(sport);
466 if (intstat & M_DUART_ISR_TX)
467 sbd_transmit_chars(sport);
468
469 status = IRQ_HANDLED;
470 }
471
472 return status;
473 }
474
475
476 static int sbd_startup(struct uart_port *uport)
477 {
478 struct sbd_port *sport = to_sport(uport);
479 unsigned int mode1;
480 int ret;
481
482 ret = request_irq(sport->port.irq, sbd_interrupt,
483 IRQF_SHARED, "sb1250-duart", sport);
484 if (ret)
485 return ret;
486
487 /* Clear the receive FIFO. */
488 sbd_receive_drain(sport);
489
490 /* Clear the interrupt registers. */
491 write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_RESET_BREAK_INT);
492 read_sbdshr(sport, R_DUART_INCHREG((uport->line) % 2));
493
494 /* Set rx/tx interrupt to FIFO available. */
495 mode1 = read_sbdchn(sport, R_DUART_MODE_REG_1);
496 mode1 &= ~(M_DUART_RX_IRQ_SEL_RXFULL | M_DUART_TX_IRQ_SEL_TXEMPT);
497 write_sbdchn(sport, R_DUART_MODE_REG_1, mode1);
498
499 /* Disable tx, enable rx. */
500 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS | M_DUART_RX_EN);
501 sport->tx_stopped = 1;
502
503 /* Enable interrupts. */
504 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2),
505 M_DUART_IMR_IN | M_DUART_IMR_RX);
506
507 return 0;
508 }
509
510 static void sbd_shutdown(struct uart_port *uport)
511 {
512 struct sbd_port *sport = to_sport(uport);
513
514 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS | M_DUART_RX_DIS);
515 sport->tx_stopped = 1;
516 free_irq(sport->port.irq, sport);
517 }
518
519
520 static void sbd_init_port(struct sbd_port *sport)
521 {
522 struct uart_port *uport = &sport->port;
523
524 if (sport->initialised)
525 return;
526
527 /* There is no DUART reset feature, so just set some sane defaults. */
528 write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_RESET_TX);
529 write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_RESET_RX);
530 write_sbdchn(sport, R_DUART_MODE_REG_1, V_DUART_BITS_PER_CHAR_8);
531 write_sbdchn(sport, R_DUART_MODE_REG_2, 0);
532 write_sbdchn(sport, R_DUART_FULL_CTL,
533 V_DUART_INT_TIME(0) | V_DUART_SIG_FULL(15));
534 write_sbdchn(sport, R_DUART_OPCR_X, 0);
535 write_sbdchn(sport, R_DUART_AUXCTL_X, 0);
536 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), 0);
537
538 sport->initialised = 1;
539 }
540
541 static void sbd_set_termios(struct uart_port *uport, struct ktermios *termios,
542 struct ktermios *old_termios)
543 {
544 struct sbd_port *sport = to_sport(uport);
545 unsigned int mode1 = 0, mode2 = 0, aux = 0;
546 unsigned int mode1mask = 0, mode2mask = 0, auxmask = 0;
547 unsigned int oldmode1, oldmode2, oldaux;
548 unsigned int baud, brg;
549 unsigned int command;
550
551 mode1mask |= ~(M_DUART_PARITY_MODE | M_DUART_PARITY_TYPE_ODD |
552 M_DUART_BITS_PER_CHAR);
553 mode2mask |= ~M_DUART_STOP_BIT_LEN_2;
554 auxmask |= ~M_DUART_CTS_CHNG_ENA;
555
556 /* Byte size. */
557 switch (termios->c_cflag & CSIZE) {
558 case CS5:
559 case CS6:
560 /* Unsupported, leave unchanged. */
561 mode1mask |= M_DUART_PARITY_MODE;
562 break;
563 case CS7:
564 mode1 |= V_DUART_BITS_PER_CHAR_7;
565 break;
566 case CS8:
567 default:
568 mode1 |= V_DUART_BITS_PER_CHAR_8;
569 break;
570 }
571
572 /* Parity and stop bits. */
573 if (termios->c_cflag & CSTOPB)
574 mode2 |= M_DUART_STOP_BIT_LEN_2;
575 else
576 mode2 |= M_DUART_STOP_BIT_LEN_1;
577 if (termios->c_cflag & PARENB)
578 mode1 |= V_DUART_PARITY_MODE_ADD;
579 else
580 mode1 |= V_DUART_PARITY_MODE_NONE;
581 if (termios->c_cflag & PARODD)
582 mode1 |= M_DUART_PARITY_TYPE_ODD;
583 else
584 mode1 |= M_DUART_PARITY_TYPE_EVEN;
585
586 baud = uart_get_baud_rate(uport, termios, old_termios, 1200, 5000000);
587 brg = V_DUART_BAUD_RATE(baud);
588 /* The actual lower bound is 1221bps, so compensate. */
589 if (brg > M_DUART_CLK_COUNTER)
590 brg = M_DUART_CLK_COUNTER;
591
592 uart_update_timeout(uport, termios->c_cflag, baud);
593
594 uport->read_status_mask = M_DUART_OVRUN_ERR;
595 if (termios->c_iflag & INPCK)
596 uport->read_status_mask |= M_DUART_FRM_ERR |
597 M_DUART_PARITY_ERR;
598 if (termios->c_iflag & (BRKINT | PARMRK))
599 uport->read_status_mask |= M_DUART_RCVD_BRK;
600
601 uport->ignore_status_mask = 0;
602 if (termios->c_iflag & IGNPAR)
603 uport->ignore_status_mask |= M_DUART_FRM_ERR |
604 M_DUART_PARITY_ERR;
605 if (termios->c_iflag & IGNBRK) {
606 uport->ignore_status_mask |= M_DUART_RCVD_BRK;
607 if (termios->c_iflag & IGNPAR)
608 uport->ignore_status_mask |= M_DUART_OVRUN_ERR;
609 }
610
611 if (termios->c_cflag & CREAD)
612 command = M_DUART_RX_EN;
613 else
614 command = M_DUART_RX_DIS;
615
616 if (termios->c_cflag & CRTSCTS)
617 aux |= M_DUART_CTS_CHNG_ENA;
618 else
619 aux &= ~M_DUART_CTS_CHNG_ENA;
620
621 spin_lock(&uport->lock);
622
623 if (sport->tx_stopped)
624 command |= M_DUART_TX_DIS;
625 else
626 command |= M_DUART_TX_EN;
627
628 oldmode1 = read_sbdchn(sport, R_DUART_MODE_REG_1) & mode1mask;
629 oldmode2 = read_sbdchn(sport, R_DUART_MODE_REG_2) & mode2mask;
630 oldaux = read_sbdchn(sport, R_DUART_AUXCTL_X) & auxmask;
631
632 if (!sport->tx_stopped)
633 sbd_line_drain(sport);
634 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS | M_DUART_RX_DIS);
635
636 write_sbdchn(sport, R_DUART_MODE_REG_1, mode1 | oldmode1);
637 write_sbdchn(sport, R_DUART_MODE_REG_2, mode2 | oldmode2);
638 write_sbdchn(sport, R_DUART_CLK_SEL, brg);
639 write_sbdchn(sport, R_DUART_AUXCTL_X, aux | oldaux);
640
641 write_sbdchn(sport, R_DUART_CMD, command);
642
643 spin_unlock(&uport->lock);
644 }
645
646
647 static const char *sbd_type(struct uart_port *uport)
648 {
649 return "SB1250 DUART";
650 }
651
652 static void sbd_release_port(struct uart_port *uport)
653 {
654 struct sbd_port *sport = to_sport(uport);
655 struct sbd_duart *duart = sport->duart;
656 int map_guard;
657
658 iounmap(sport->memctrl);
659 sport->memctrl = NULL;
660 iounmap(uport->membase);
661 uport->membase = NULL;
662
663 map_guard = atomic_add_return(-1, &duart->map_guard);
664 if (!map_guard)
665 release_mem_region(duart->mapctrl, DUART_CHANREG_SPACING);
666 release_mem_region(uport->mapbase, DUART_CHANREG_SPACING);
667 }
668
669 static int sbd_map_port(struct uart_port *uport)
670 {
671 const char *err = KERN_ERR "sbd: Cannot map MMIO\n";
672 struct sbd_port *sport = to_sport(uport);
673 struct sbd_duart *duart = sport->duart;
674
675 if (!uport->membase)
676 uport->membase = ioremap_nocache(uport->mapbase,
677 DUART_CHANREG_SPACING);
678 if (!uport->membase) {
679 printk(err);
680 return -ENOMEM;
681 }
682
683 if (!sport->memctrl)
684 sport->memctrl = ioremap_nocache(duart->mapctrl,
685 DUART_CHANREG_SPACING);
686 if (!sport->memctrl) {
687 printk(err);
688 iounmap(uport->membase);
689 uport->membase = NULL;
690 return -ENOMEM;
691 }
692
693 return 0;
694 }
695
696 static int sbd_request_port(struct uart_port *uport)
697 {
698 const char *err = KERN_ERR "sbd: Unable to reserve MMIO resource\n";
699 struct sbd_duart *duart = to_sport(uport)->duart;
700 int map_guard;
701 int ret = 0;
702
703 if (!request_mem_region(uport->mapbase, DUART_CHANREG_SPACING,
704 "sb1250-duart")) {
705 printk(err);
706 return -EBUSY;
707 }
708 map_guard = atomic_add_return(1, &duart->map_guard);
709 if (map_guard == 1) {
710 if (!request_mem_region(duart->mapctrl, DUART_CHANREG_SPACING,
711 "sb1250-duart")) {
712 atomic_add(-1, &duart->map_guard);
713 printk(err);
714 ret = -EBUSY;
715 }
716 }
717 if (!ret) {
718 ret = sbd_map_port(uport);
719 if (ret) {
720 map_guard = atomic_add_return(-1, &duart->map_guard);
721 if (!map_guard)
722 release_mem_region(duart->mapctrl,
723 DUART_CHANREG_SPACING);
724 }
725 }
726 if (ret) {
727 release_mem_region(uport->mapbase, DUART_CHANREG_SPACING);
728 return ret;
729 }
730 return 0;
731 }
732
733 static void sbd_config_port(struct uart_port *uport, int flags)
734 {
735 struct sbd_port *sport = to_sport(uport);
736
737 if (flags & UART_CONFIG_TYPE) {
738 if (sbd_request_port(uport))
739 return;
740
741 uport->type = PORT_SB1250_DUART;
742
743 sbd_init_port(sport);
744 }
745 }
746
747 static int sbd_verify_port(struct uart_port *uport, struct serial_struct *ser)
748 {
749 int ret = 0;
750
751 if (ser->type != PORT_UNKNOWN && ser->type != PORT_SB1250_DUART)
752 ret = -EINVAL;
753 if (ser->irq != uport->irq)
754 ret = -EINVAL;
755 if (ser->baud_base != uport->uartclk / 16)
756 ret = -EINVAL;
757 return ret;
758 }
759
760
761 static const struct uart_ops sbd_ops = {
762 .tx_empty = sbd_tx_empty,
763 .set_mctrl = sbd_set_mctrl,
764 .get_mctrl = sbd_get_mctrl,
765 .stop_tx = sbd_stop_tx,
766 .start_tx = sbd_start_tx,
767 .stop_rx = sbd_stop_rx,
768 .enable_ms = sbd_enable_ms,
769 .break_ctl = sbd_break_ctl,
770 .startup = sbd_startup,
771 .shutdown = sbd_shutdown,
772 .set_termios = sbd_set_termios,
773 .type = sbd_type,
774 .release_port = sbd_release_port,
775 .request_port = sbd_request_port,
776 .config_port = sbd_config_port,
777 .verify_port = sbd_verify_port,
778 };
779
780 /* Initialize SB1250 DUART port structures. */
781 static void __init sbd_probe_duarts(void)
782 {
783 static int probed;
784 int chip, side;
785 int max_lines, line;
786
787 if (probed)
788 return;
789
790 /* Set the number of available units based on the SOC type. */
791 switch (soc_type) {
792 case K_SYS_SOC_TYPE_BCM1x55:
793 case K_SYS_SOC_TYPE_BCM1x80:
794 max_lines = 4;
795 break;
796 default:
797 /* Assume at least two serial ports at the normal address. */
798 max_lines = 2;
799 break;
800 }
801
802 probed = 1;
803
804 for (chip = 0, line = 0; chip < DUART_MAX_CHIP && line < max_lines;
805 chip++) {
806 sbd_duarts[chip].mapctrl = SBD_CTRLREGS(line);
807
808 for (side = 0; side < DUART_MAX_SIDE && line < max_lines;
809 side++, line++) {
810 struct sbd_port *sport = &sbd_duarts[chip].sport[side];
811 struct uart_port *uport = &sport->port;
812
813 sport->duart = &sbd_duarts[chip];
814
815 uport->irq = SBD_INT(line);
816 uport->uartclk = 100000000 / 20 * 16;
817 uport->fifosize = 16;
818 uport->iotype = UPIO_MEM;
819 uport->flags = UPF_BOOT_AUTOCONF;
820 uport->ops = &sbd_ops;
821 uport->line = line;
822 uport->mapbase = SBD_CHANREGS(line);
823 }
824 }
825 }
826
827
828 #ifdef CONFIG_SERIAL_SB1250_DUART_CONSOLE
829 /*
830 * Serial console stuff. Very basic, polling driver for doing serial
831 * console output. The console_lock is held by the caller, so we
832 * shouldn't be interrupted for more console activity.
833 */
834 static void sbd_console_putchar(struct uart_port *uport, int ch)
835 {
836 struct sbd_port *sport = to_sport(uport);
837
838 sbd_transmit_drain(sport);
839 write_sbdchn(sport, R_DUART_TX_HOLD, ch);
840 }
841
842 static void sbd_console_write(struct console *co, const char *s,
843 unsigned int count)
844 {
845 int chip = co->index / DUART_MAX_SIDE;
846 int side = co->index % DUART_MAX_SIDE;
847 struct sbd_port *sport = &sbd_duarts[chip].sport[side];
848 struct uart_port *uport = &sport->port;
849 unsigned long flags;
850 unsigned int mask;
851
852 /* Disable transmit interrupts and enable the transmitter. */
853 spin_lock_irqsave(&uport->lock, flags);
854 mask = read_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2));
855 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2),
856 mask & ~M_DUART_IMR_TX);
857 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_EN);
858 spin_unlock_irqrestore(&uport->lock, flags);
859
860 uart_console_write(&sport->port, s, count, sbd_console_putchar);
861
862 /* Restore transmit interrupts and the transmitter enable. */
863 spin_lock_irqsave(&uport->lock, flags);
864 sbd_line_drain(sport);
865 if (sport->tx_stopped)
866 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS);
867 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), mask);
868 spin_unlock_irqrestore(&uport->lock, flags);
869 }
870
871 static int __init sbd_console_setup(struct console *co, char *options)
872 {
873 int chip = co->index / DUART_MAX_SIDE;
874 int side = co->index % DUART_MAX_SIDE;
875 struct sbd_port *sport = &sbd_duarts[chip].sport[side];
876 struct uart_port *uport = &sport->port;
877 int baud = 115200;
878 int bits = 8;
879 int parity = 'n';
880 int flow = 'n';
881 int ret;
882
883 if (!sport->duart)
884 return -ENXIO;
885
886 ret = sbd_map_port(uport);
887 if (ret)
888 return ret;
889
890 sbd_init_port(sport);
891
892 if (options)
893 uart_parse_options(options, &baud, &parity, &bits, &flow);
894 return uart_set_options(uport, co, baud, parity, bits, flow);
895 }
896
897 static struct uart_driver sbd_reg;
898 static struct console sbd_console = {
899 .name = "duart",
900 .write = sbd_console_write,
901 .device = uart_console_device,
902 .setup = sbd_console_setup,
903 .flags = CON_PRINTBUFFER,
904 .index = -1,
905 .data = &sbd_reg
906 };
907
908 static int __init sbd_serial_console_init(void)
909 {
910 sbd_probe_duarts();
911 register_console(&sbd_console);
912
913 return 0;
914 }
915
916 console_initcall(sbd_serial_console_init);
917
918 #define SERIAL_SB1250_DUART_CONSOLE &sbd_console
919 #else
920 #define SERIAL_SB1250_DUART_CONSOLE NULL
921 #endif /* CONFIG_SERIAL_SB1250_DUART_CONSOLE */
922
923
924 static struct uart_driver sbd_reg = {
925 .owner = THIS_MODULE,
926 .driver_name = "sb1250_duart",
927 .dev_name = "duart",
928 .major = TTY_MAJOR,
929 .minor = SB1250_DUART_MINOR_BASE,
930 .nr = DUART_MAX_CHIP * DUART_MAX_SIDE,
931 .cons = SERIAL_SB1250_DUART_CONSOLE,
932 };
933
934 /* Set up the driver and register it. */
935 static int __init sbd_init(void)
936 {
937 int i, ret;
938
939 sbd_probe_duarts();
940
941 ret = uart_register_driver(&sbd_reg);
942 if (ret)
943 return ret;
944
945 for (i = 0; i < DUART_MAX_CHIP * DUART_MAX_SIDE; i++) {
946 struct sbd_duart *duart = &sbd_duarts[i / DUART_MAX_SIDE];
947 struct sbd_port *sport = &duart->sport[i % DUART_MAX_SIDE];
948 struct uart_port *uport = &sport->port;
949
950 if (sport->duart)
951 uart_add_one_port(&sbd_reg, uport);
952 }
953
954 return 0;
955 }
956
957 /* Unload the driver. Unregister stuff, get ready to go away. */
958 static void __exit sbd_exit(void)
959 {
960 int i;
961
962 for (i = DUART_MAX_CHIP * DUART_MAX_SIDE - 1; i >= 0; i--) {
963 struct sbd_duart *duart = &sbd_duarts[i / DUART_MAX_SIDE];
964 struct sbd_port *sport = &duart->sport[i % DUART_MAX_SIDE];
965 struct uart_port *uport = &sport->port;
966
967 if (sport->duart)
968 uart_remove_one_port(&sbd_reg, uport);
969 }
970
971 uart_unregister_driver(&sbd_reg);
972 }
973
974 module_init(sbd_init);
975 module_exit(sbd_exit);
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