fix a kmap leak in virtio_console
[linux/fpc-iii.git] / drivers / tty / serial / sb1250-duart.c
bloba7cdec2962dd8cb117a028a39b644e378129aec3
1 /*
2 * Support for the asynchronous serial interface (DUART) included
3 * in the BCM1250 and derived System-On-a-Chip (SOC) devices.
5 * Copyright (c) 2007 Maciej W. Rozycki
7 * Derived from drivers/char/sb1250_duart.c for which the following
8 * copyright applies:
10 * Copyright (c) 2000, 2001, 2002, 2003, 2004 Broadcom Corporation
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.
17 * References:
19 * "BCM1250/BCM1125/BCM1125H User Manual", Broadcom Corporation
22 #if defined(CONFIG_SERIAL_SB1250_DUART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
23 #define SUPPORT_SYSRQ
24 #endif
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/module.h>
35 #include <linux/major.h>
36 #include <linux/serial.h>
37 #include <linux/serial_core.h>
38 #include <linux/spinlock.h>
39 #include <linux/sysrq.h>
40 #include <linux/tty.h>
41 #include <linux/tty_flip.h>
42 #include <linux/types.h>
44 #include <linux/atomic.h>
45 #include <asm/io.h>
46 #include <asm/war.h>
48 #include <asm/sibyte/sb1250.h>
49 #include <asm/sibyte/sb1250_uart.h>
50 #include <asm/sibyte/swarm.h>
53 #if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
54 #include <asm/sibyte/bcm1480_regs.h>
55 #include <asm/sibyte/bcm1480_int.h>
57 #define SBD_CHANREGS(line) A_BCM1480_DUART_CHANREG((line), 0)
58 #define SBD_CTRLREGS(line) A_BCM1480_DUART_CTRLREG((line), 0)
59 #define SBD_INT(line) (K_BCM1480_INT_UART_0 + (line))
61 #define DUART_CHANREG_SPACING BCM1480_DUART_CHANREG_SPACING
63 #define R_DUART_IMRREG(line) R_BCM1480_DUART_IMRREG(line)
64 #define R_DUART_INCHREG(line) R_BCM1480_DUART_INCHREG(line)
65 #define R_DUART_ISRREG(line) R_BCM1480_DUART_ISRREG(line)
67 #elif defined(CONFIG_SIBYTE_SB1250) || defined(CONFIG_SIBYTE_BCM112X)
68 #include <asm/sibyte/sb1250_regs.h>
69 #include <asm/sibyte/sb1250_int.h>
71 #define SBD_CHANREGS(line) A_DUART_CHANREG((line), 0)
72 #define SBD_CTRLREGS(line) A_DUART_CTRLREG(0)
73 #define SBD_INT(line) (K_INT_UART_0 + (line))
75 #else
76 #error invalid SB1250 UART configuration
78 #endif
81 MODULE_AUTHOR("Maciej W. Rozycki <macro@linux-mips.org>");
82 MODULE_DESCRIPTION("BCM1xxx on-chip DUART serial driver");
83 MODULE_LICENSE("GPL");
86 #define DUART_MAX_CHIP 2
87 #define DUART_MAX_SIDE 2
90 * Per-port state.
92 struct sbd_port {
93 struct sbd_duart *duart;
94 struct uart_port port;
95 unsigned char __iomem *memctrl;
96 int tx_stopped;
97 int initialised;
101 * Per-DUART state for the shared register space.
103 struct sbd_duart {
104 struct sbd_port sport[2];
105 unsigned long mapctrl;
106 atomic_t map_guard;
109 #define to_sport(uport) container_of(uport, struct sbd_port, port)
111 static struct sbd_duart sbd_duarts[DUART_MAX_CHIP];
115 * Reading and writing SB1250 DUART registers.
117 * There are three register spaces: two per-channel ones and
118 * a shared one. We have to define accessors appropriately.
119 * All registers are 64-bit and all but the Baud Rate Clock
120 * registers only define 8 least significant bits. There is
121 * also a workaround to take into account. Raw accessors use
122 * the full register width, but cooked ones truncate it
123 * intentionally so that the rest of the driver does not care.
125 static u64 __read_sbdchn(struct sbd_port *sport, int reg)
127 void __iomem *csr = sport->port.membase + reg;
129 return __raw_readq(csr);
132 static u64 __read_sbdshr(struct sbd_port *sport, int reg)
134 void __iomem *csr = sport->memctrl + reg;
136 return __raw_readq(csr);
139 static void __write_sbdchn(struct sbd_port *sport, int reg, u64 value)
141 void __iomem *csr = sport->port.membase + reg;
143 __raw_writeq(value, csr);
146 static void __write_sbdshr(struct sbd_port *sport, int reg, u64 value)
148 void __iomem *csr = sport->memctrl + reg;
150 __raw_writeq(value, csr);
154 * In bug 1956, we get glitches that can mess up uart registers. This
155 * "read-mode-reg after any register access" is an accepted workaround.
157 static void __war_sbd1956(struct sbd_port *sport)
159 __read_sbdchn(sport, R_DUART_MODE_REG_1);
160 __read_sbdchn(sport, R_DUART_MODE_REG_2);
163 static unsigned char read_sbdchn(struct sbd_port *sport, int reg)
165 unsigned char retval;
167 retval = __read_sbdchn(sport, reg);
168 if (SIBYTE_1956_WAR)
169 __war_sbd1956(sport);
170 return retval;
173 static unsigned char read_sbdshr(struct sbd_port *sport, int reg)
175 unsigned char retval;
177 retval = __read_sbdshr(sport, reg);
178 if (SIBYTE_1956_WAR)
179 __war_sbd1956(sport);
180 return retval;
183 static void write_sbdchn(struct sbd_port *sport, int reg, unsigned int value)
185 __write_sbdchn(sport, reg, value);
186 if (SIBYTE_1956_WAR)
187 __war_sbd1956(sport);
190 static void write_sbdshr(struct sbd_port *sport, int reg, unsigned int value)
192 __write_sbdshr(sport, reg, value);
193 if (SIBYTE_1956_WAR)
194 __war_sbd1956(sport);
198 static int sbd_receive_ready(struct sbd_port *sport)
200 return read_sbdchn(sport, R_DUART_STATUS) & M_DUART_RX_RDY;
203 static int sbd_receive_drain(struct sbd_port *sport)
205 int loops = 10000;
207 while (sbd_receive_ready(sport) && --loops)
208 read_sbdchn(sport, R_DUART_RX_HOLD);
209 return loops;
212 static int __maybe_unused sbd_transmit_ready(struct sbd_port *sport)
214 return read_sbdchn(sport, R_DUART_STATUS) & M_DUART_TX_RDY;
217 static int __maybe_unused sbd_transmit_drain(struct sbd_port *sport)
219 int loops = 10000;
221 while (!sbd_transmit_ready(sport) && --loops)
222 udelay(2);
223 return loops;
226 static int sbd_transmit_empty(struct sbd_port *sport)
228 return read_sbdchn(sport, R_DUART_STATUS) & M_DUART_TX_EMT;
231 static int sbd_line_drain(struct sbd_port *sport)
233 int loops = 10000;
235 while (!sbd_transmit_empty(sport) && --loops)
236 udelay(2);
237 return loops;
241 static unsigned int sbd_tx_empty(struct uart_port *uport)
243 struct sbd_port *sport = to_sport(uport);
245 return sbd_transmit_empty(sport) ? TIOCSER_TEMT : 0;
248 static unsigned int sbd_get_mctrl(struct uart_port *uport)
250 struct sbd_port *sport = to_sport(uport);
251 unsigned int mctrl, status;
253 status = read_sbdshr(sport, R_DUART_IN_PORT);
254 status >>= (uport->line) % 2;
255 mctrl = (!(status & M_DUART_IN_PIN0_VAL) ? TIOCM_CTS : 0) |
256 (!(status & M_DUART_IN_PIN4_VAL) ? TIOCM_CAR : 0) |
257 (!(status & M_DUART_RIN0_PIN) ? TIOCM_RNG : 0) |
258 (!(status & M_DUART_IN_PIN2_VAL) ? TIOCM_DSR : 0);
259 return mctrl;
262 static void sbd_set_mctrl(struct uart_port *uport, unsigned int mctrl)
264 struct sbd_port *sport = to_sport(uport);
265 unsigned int clr = 0, set = 0, mode2;
267 if (mctrl & TIOCM_DTR)
268 set |= M_DUART_SET_OPR2;
269 else
270 clr |= M_DUART_CLR_OPR2;
271 if (mctrl & TIOCM_RTS)
272 set |= M_DUART_SET_OPR0;
273 else
274 clr |= M_DUART_CLR_OPR0;
275 clr <<= (uport->line) % 2;
276 set <<= (uport->line) % 2;
278 mode2 = read_sbdchn(sport, R_DUART_MODE_REG_2);
279 mode2 &= ~M_DUART_CHAN_MODE;
280 if (mctrl & TIOCM_LOOP)
281 mode2 |= V_DUART_CHAN_MODE_LCL_LOOP;
282 else
283 mode2 |= V_DUART_CHAN_MODE_NORMAL;
285 write_sbdshr(sport, R_DUART_CLEAR_OPR, clr);
286 write_sbdshr(sport, R_DUART_SET_OPR, set);
287 write_sbdchn(sport, R_DUART_MODE_REG_2, mode2);
290 static void sbd_stop_tx(struct uart_port *uport)
292 struct sbd_port *sport = to_sport(uport);
294 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS);
295 sport->tx_stopped = 1;
298 static void sbd_start_tx(struct uart_port *uport)
300 struct sbd_port *sport = to_sport(uport);
301 unsigned int mask;
303 /* Enable tx interrupts. */
304 mask = read_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2));
305 mask |= M_DUART_IMR_TX;
306 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), mask);
308 /* Go!, go!, go!... */
309 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_EN);
310 sport->tx_stopped = 0;
313 static void sbd_stop_rx(struct uart_port *uport)
315 struct sbd_port *sport = to_sport(uport);
317 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), 0);
320 static void sbd_enable_ms(struct uart_port *uport)
322 struct sbd_port *sport = to_sport(uport);
324 write_sbdchn(sport, R_DUART_AUXCTL_X,
325 M_DUART_CIN_CHNG_ENA | M_DUART_CTS_CHNG_ENA);
328 static void sbd_break_ctl(struct uart_port *uport, int break_state)
330 struct sbd_port *sport = to_sport(uport);
332 if (break_state == -1)
333 write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_START_BREAK);
334 else
335 write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_STOP_BREAK);
339 static void sbd_receive_chars(struct sbd_port *sport)
341 struct uart_port *uport = &sport->port;
342 struct uart_icount *icount;
343 unsigned int status, ch, flag;
344 int count;
346 for (count = 16; count; count--) {
347 status = read_sbdchn(sport, R_DUART_STATUS);
348 if (!(status & M_DUART_RX_RDY))
349 break;
351 ch = read_sbdchn(sport, R_DUART_RX_HOLD);
353 flag = TTY_NORMAL;
355 icount = &uport->icount;
356 icount->rx++;
358 if (unlikely(status &
359 (M_DUART_RCVD_BRK | M_DUART_FRM_ERR |
360 M_DUART_PARITY_ERR | M_DUART_OVRUN_ERR))) {
361 if (status & M_DUART_RCVD_BRK) {
362 icount->brk++;
363 if (uart_handle_break(uport))
364 continue;
365 } else if (status & M_DUART_FRM_ERR)
366 icount->frame++;
367 else if (status & M_DUART_PARITY_ERR)
368 icount->parity++;
369 if (status & M_DUART_OVRUN_ERR)
370 icount->overrun++;
372 status &= uport->read_status_mask;
373 if (status & M_DUART_RCVD_BRK)
374 flag = TTY_BREAK;
375 else if (status & M_DUART_FRM_ERR)
376 flag = TTY_FRAME;
377 else if (status & M_DUART_PARITY_ERR)
378 flag = TTY_PARITY;
381 if (uart_handle_sysrq_char(uport, ch))
382 continue;
384 uart_insert_char(uport, status, M_DUART_OVRUN_ERR, ch, flag);
387 tty_flip_buffer_push(&uport->state->port);
390 static void sbd_transmit_chars(struct sbd_port *sport)
392 struct uart_port *uport = &sport->port;
393 struct circ_buf *xmit = &sport->port.state->xmit;
394 unsigned int mask;
395 int stop_tx;
397 /* XON/XOFF chars. */
398 if (sport->port.x_char) {
399 write_sbdchn(sport, R_DUART_TX_HOLD, sport->port.x_char);
400 sport->port.icount.tx++;
401 sport->port.x_char = 0;
402 return;
405 /* If nothing to do or stopped or hardware stopped. */
406 stop_tx = (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port));
408 /* Send char. */
409 if (!stop_tx) {
410 write_sbdchn(sport, R_DUART_TX_HOLD, xmit->buf[xmit->tail]);
411 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
412 sport->port.icount.tx++;
414 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
415 uart_write_wakeup(&sport->port);
418 /* Are we are done? */
419 if (stop_tx || uart_circ_empty(xmit)) {
420 /* Disable tx interrupts. */
421 mask = read_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2));
422 mask &= ~M_DUART_IMR_TX;
423 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), mask);
427 static void sbd_status_handle(struct sbd_port *sport)
429 struct uart_port *uport = &sport->port;
430 unsigned int delta;
432 delta = read_sbdshr(sport, R_DUART_INCHREG((uport->line) % 2));
433 delta >>= (uport->line) % 2;
435 if (delta & (M_DUART_IN_PIN0_VAL << S_DUART_IN_PIN_CHNG))
436 uart_handle_cts_change(uport, !(delta & M_DUART_IN_PIN0_VAL));
438 if (delta & (M_DUART_IN_PIN2_VAL << S_DUART_IN_PIN_CHNG))
439 uport->icount.dsr++;
441 if (delta & ((M_DUART_IN_PIN2_VAL | M_DUART_IN_PIN0_VAL) <<
442 S_DUART_IN_PIN_CHNG))
443 wake_up_interruptible(&uport->state->port.delta_msr_wait);
446 static irqreturn_t sbd_interrupt(int irq, void *dev_id)
448 struct sbd_port *sport = dev_id;
449 struct uart_port *uport = &sport->port;
450 irqreturn_t status = IRQ_NONE;
451 unsigned int intstat;
452 int count;
454 for (count = 16; count; count--) {
455 intstat = read_sbdshr(sport,
456 R_DUART_ISRREG((uport->line) % 2));
457 intstat &= read_sbdshr(sport,
458 R_DUART_IMRREG((uport->line) % 2));
459 intstat &= M_DUART_ISR_ALL;
460 if (!intstat)
461 break;
463 if (intstat & M_DUART_ISR_RX)
464 sbd_receive_chars(sport);
465 if (intstat & M_DUART_ISR_IN)
466 sbd_status_handle(sport);
467 if (intstat & M_DUART_ISR_TX)
468 sbd_transmit_chars(sport);
470 status = IRQ_HANDLED;
473 return status;
477 static int sbd_startup(struct uart_port *uport)
479 struct sbd_port *sport = to_sport(uport);
480 unsigned int mode1;
481 int ret;
483 ret = request_irq(sport->port.irq, sbd_interrupt,
484 IRQF_SHARED, "sb1250-duart", sport);
485 if (ret)
486 return ret;
488 /* Clear the receive FIFO. */
489 sbd_receive_drain(sport);
491 /* Clear the interrupt registers. */
492 write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_RESET_BREAK_INT);
493 read_sbdshr(sport, R_DUART_INCHREG((uport->line) % 2));
495 /* Set rx/tx interrupt to FIFO available. */
496 mode1 = read_sbdchn(sport, R_DUART_MODE_REG_1);
497 mode1 &= ~(M_DUART_RX_IRQ_SEL_RXFULL | M_DUART_TX_IRQ_SEL_TXEMPT);
498 write_sbdchn(sport, R_DUART_MODE_REG_1, mode1);
500 /* Disable tx, enable rx. */
501 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS | M_DUART_RX_EN);
502 sport->tx_stopped = 1;
504 /* Enable interrupts. */
505 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2),
506 M_DUART_IMR_IN | M_DUART_IMR_RX);
508 return 0;
511 static void sbd_shutdown(struct uart_port *uport)
513 struct sbd_port *sport = to_sport(uport);
515 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS | M_DUART_RX_DIS);
516 sport->tx_stopped = 1;
517 free_irq(sport->port.irq, sport);
521 static void sbd_init_port(struct sbd_port *sport)
523 struct uart_port *uport = &sport->port;
525 if (sport->initialised)
526 return;
528 /* There is no DUART reset feature, so just set some sane defaults. */
529 write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_RESET_TX);
530 write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_RESET_RX);
531 write_sbdchn(sport, R_DUART_MODE_REG_1, V_DUART_BITS_PER_CHAR_8);
532 write_sbdchn(sport, R_DUART_MODE_REG_2, 0);
533 write_sbdchn(sport, R_DUART_FULL_CTL,
534 V_DUART_INT_TIME(0) | V_DUART_SIG_FULL(15));
535 write_sbdchn(sport, R_DUART_OPCR_X, 0);
536 write_sbdchn(sport, R_DUART_AUXCTL_X, 0);
537 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), 0);
539 sport->initialised = 1;
542 static void sbd_set_termios(struct uart_port *uport, struct ktermios *termios,
543 struct ktermios *old_termios)
545 struct sbd_port *sport = to_sport(uport);
546 unsigned int mode1 = 0, mode2 = 0, aux = 0;
547 unsigned int mode1mask = 0, mode2mask = 0, auxmask = 0;
548 unsigned int oldmode1, oldmode2, oldaux;
549 unsigned int baud, brg;
550 unsigned int command;
552 mode1mask |= ~(M_DUART_PARITY_MODE | M_DUART_PARITY_TYPE_ODD |
553 M_DUART_BITS_PER_CHAR);
554 mode2mask |= ~M_DUART_STOP_BIT_LEN_2;
555 auxmask |= ~M_DUART_CTS_CHNG_ENA;
557 /* Byte size. */
558 switch (termios->c_cflag & CSIZE) {
559 case CS5:
560 case CS6:
561 /* Unsupported, leave unchanged. */
562 mode1mask |= M_DUART_PARITY_MODE;
563 break;
564 case CS7:
565 mode1 |= V_DUART_BITS_PER_CHAR_7;
566 break;
567 case CS8:
568 default:
569 mode1 |= V_DUART_BITS_PER_CHAR_8;
570 break;
573 /* Parity and stop bits. */
574 if (termios->c_cflag & CSTOPB)
575 mode2 |= M_DUART_STOP_BIT_LEN_2;
576 else
577 mode2 |= M_DUART_STOP_BIT_LEN_1;
578 if (termios->c_cflag & PARENB)
579 mode1 |= V_DUART_PARITY_MODE_ADD;
580 else
581 mode1 |= V_DUART_PARITY_MODE_NONE;
582 if (termios->c_cflag & PARODD)
583 mode1 |= M_DUART_PARITY_TYPE_ODD;
584 else
585 mode1 |= M_DUART_PARITY_TYPE_EVEN;
587 baud = uart_get_baud_rate(uport, termios, old_termios, 1200, 5000000);
588 brg = V_DUART_BAUD_RATE(baud);
589 /* The actual lower bound is 1221bps, so compensate. */
590 if (brg > M_DUART_CLK_COUNTER)
591 brg = M_DUART_CLK_COUNTER;
593 uart_update_timeout(uport, termios->c_cflag, baud);
595 uport->read_status_mask = M_DUART_OVRUN_ERR;
596 if (termios->c_iflag & INPCK)
597 uport->read_status_mask |= M_DUART_FRM_ERR |
598 M_DUART_PARITY_ERR;
599 if (termios->c_iflag & (BRKINT | PARMRK))
600 uport->read_status_mask |= M_DUART_RCVD_BRK;
602 uport->ignore_status_mask = 0;
603 if (termios->c_iflag & IGNPAR)
604 uport->ignore_status_mask |= M_DUART_FRM_ERR |
605 M_DUART_PARITY_ERR;
606 if (termios->c_iflag & IGNBRK) {
607 uport->ignore_status_mask |= M_DUART_RCVD_BRK;
608 if (termios->c_iflag & IGNPAR)
609 uport->ignore_status_mask |= M_DUART_OVRUN_ERR;
612 if (termios->c_cflag & CREAD)
613 command = M_DUART_RX_EN;
614 else
615 command = M_DUART_RX_DIS;
617 if (termios->c_cflag & CRTSCTS)
618 aux |= M_DUART_CTS_CHNG_ENA;
619 else
620 aux &= ~M_DUART_CTS_CHNG_ENA;
622 spin_lock(&uport->lock);
624 if (sport->tx_stopped)
625 command |= M_DUART_TX_DIS;
626 else
627 command |= M_DUART_TX_EN;
629 oldmode1 = read_sbdchn(sport, R_DUART_MODE_REG_1) & mode1mask;
630 oldmode2 = read_sbdchn(sport, R_DUART_MODE_REG_2) & mode2mask;
631 oldaux = read_sbdchn(sport, R_DUART_AUXCTL_X) & auxmask;
633 if (!sport->tx_stopped)
634 sbd_line_drain(sport);
635 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS | M_DUART_RX_DIS);
637 write_sbdchn(sport, R_DUART_MODE_REG_1, mode1 | oldmode1);
638 write_sbdchn(sport, R_DUART_MODE_REG_2, mode2 | oldmode2);
639 write_sbdchn(sport, R_DUART_CLK_SEL, brg);
640 write_sbdchn(sport, R_DUART_AUXCTL_X, aux | oldaux);
642 write_sbdchn(sport, R_DUART_CMD, command);
644 spin_unlock(&uport->lock);
648 static const char *sbd_type(struct uart_port *uport)
650 return "SB1250 DUART";
653 static void sbd_release_port(struct uart_port *uport)
655 struct sbd_port *sport = to_sport(uport);
656 struct sbd_duart *duart = sport->duart;
657 int map_guard;
659 iounmap(sport->memctrl);
660 sport->memctrl = NULL;
661 iounmap(uport->membase);
662 uport->membase = NULL;
664 map_guard = atomic_add_return(-1, &duart->map_guard);
665 if (!map_guard)
666 release_mem_region(duart->mapctrl, DUART_CHANREG_SPACING);
667 release_mem_region(uport->mapbase, DUART_CHANREG_SPACING);
670 static int sbd_map_port(struct uart_port *uport)
672 const char *err = KERN_ERR "sbd: Cannot map MMIO\n";
673 struct sbd_port *sport = to_sport(uport);
674 struct sbd_duart *duart = sport->duart;
676 if (!uport->membase)
677 uport->membase = ioremap_nocache(uport->mapbase,
678 DUART_CHANREG_SPACING);
679 if (!uport->membase) {
680 printk(err);
681 return -ENOMEM;
684 if (!sport->memctrl)
685 sport->memctrl = ioremap_nocache(duart->mapctrl,
686 DUART_CHANREG_SPACING);
687 if (!sport->memctrl) {
688 printk(err);
689 iounmap(uport->membase);
690 uport->membase = NULL;
691 return -ENOMEM;
694 return 0;
697 static int sbd_request_port(struct uart_port *uport)
699 const char *err = KERN_ERR "sbd: Unable to reserve MMIO resource\n";
700 struct sbd_duart *duart = to_sport(uport)->duart;
701 int map_guard;
702 int ret = 0;
704 if (!request_mem_region(uport->mapbase, DUART_CHANREG_SPACING,
705 "sb1250-duart")) {
706 printk(err);
707 return -EBUSY;
709 map_guard = atomic_add_return(1, &duart->map_guard);
710 if (map_guard == 1) {
711 if (!request_mem_region(duart->mapctrl, DUART_CHANREG_SPACING,
712 "sb1250-duart")) {
713 atomic_add(-1, &duart->map_guard);
714 printk(err);
715 ret = -EBUSY;
718 if (!ret) {
719 ret = sbd_map_port(uport);
720 if (ret) {
721 map_guard = atomic_add_return(-1, &duart->map_guard);
722 if (!map_guard)
723 release_mem_region(duart->mapctrl,
724 DUART_CHANREG_SPACING);
727 if (ret) {
728 release_mem_region(uport->mapbase, DUART_CHANREG_SPACING);
729 return ret;
731 return 0;
734 static void sbd_config_port(struct uart_port *uport, int flags)
736 struct sbd_port *sport = to_sport(uport);
738 if (flags & UART_CONFIG_TYPE) {
739 if (sbd_request_port(uport))
740 return;
742 uport->type = PORT_SB1250_DUART;
744 sbd_init_port(sport);
748 static int sbd_verify_port(struct uart_port *uport, struct serial_struct *ser)
750 int ret = 0;
752 if (ser->type != PORT_UNKNOWN && ser->type != PORT_SB1250_DUART)
753 ret = -EINVAL;
754 if (ser->irq != uport->irq)
755 ret = -EINVAL;
756 if (ser->baud_base != uport->uartclk / 16)
757 ret = -EINVAL;
758 return ret;
762 static const struct uart_ops sbd_ops = {
763 .tx_empty = sbd_tx_empty,
764 .set_mctrl = sbd_set_mctrl,
765 .get_mctrl = sbd_get_mctrl,
766 .stop_tx = sbd_stop_tx,
767 .start_tx = sbd_start_tx,
768 .stop_rx = sbd_stop_rx,
769 .enable_ms = sbd_enable_ms,
770 .break_ctl = sbd_break_ctl,
771 .startup = sbd_startup,
772 .shutdown = sbd_shutdown,
773 .set_termios = sbd_set_termios,
774 .type = sbd_type,
775 .release_port = sbd_release_port,
776 .request_port = sbd_request_port,
777 .config_port = sbd_config_port,
778 .verify_port = sbd_verify_port,
781 /* Initialize SB1250 DUART port structures. */
782 static void __init sbd_probe_duarts(void)
784 static int probed;
785 int chip, side;
786 int max_lines, line;
788 if (probed)
789 return;
791 /* Set the number of available units based on the SOC type. */
792 switch (soc_type) {
793 case K_SYS_SOC_TYPE_BCM1x55:
794 case K_SYS_SOC_TYPE_BCM1x80:
795 max_lines = 4;
796 break;
797 default:
798 /* Assume at least two serial ports at the normal address. */
799 max_lines = 2;
800 break;
803 probed = 1;
805 for (chip = 0, line = 0; chip < DUART_MAX_CHIP && line < max_lines;
806 chip++) {
807 sbd_duarts[chip].mapctrl = SBD_CTRLREGS(line);
809 for (side = 0; side < DUART_MAX_SIDE && line < max_lines;
810 side++, line++) {
811 struct sbd_port *sport = &sbd_duarts[chip].sport[side];
812 struct uart_port *uport = &sport->port;
814 sport->duart = &sbd_duarts[chip];
816 uport->irq = SBD_INT(line);
817 uport->uartclk = 100000000 / 20 * 16;
818 uport->fifosize = 16;
819 uport->iotype = UPIO_MEM;
820 uport->flags = UPF_BOOT_AUTOCONF;
821 uport->ops = &sbd_ops;
822 uport->line = line;
823 uport->mapbase = SBD_CHANREGS(line);
829 #ifdef CONFIG_SERIAL_SB1250_DUART_CONSOLE
831 * Serial console stuff. Very basic, polling driver for doing serial
832 * console output. The console_lock is held by the caller, so we
833 * shouldn't be interrupted for more console activity.
835 static void sbd_console_putchar(struct uart_port *uport, int ch)
837 struct sbd_port *sport = to_sport(uport);
839 sbd_transmit_drain(sport);
840 write_sbdchn(sport, R_DUART_TX_HOLD, ch);
843 static void sbd_console_write(struct console *co, const char *s,
844 unsigned int count)
846 int chip = co->index / DUART_MAX_SIDE;
847 int side = co->index % DUART_MAX_SIDE;
848 struct sbd_port *sport = &sbd_duarts[chip].sport[side];
849 struct uart_port *uport = &sport->port;
850 unsigned long flags;
851 unsigned int mask;
853 /* Disable transmit interrupts and enable the transmitter. */
854 spin_lock_irqsave(&uport->lock, flags);
855 mask = read_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2));
856 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2),
857 mask & ~M_DUART_IMR_TX);
858 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_EN);
859 spin_unlock_irqrestore(&uport->lock, flags);
861 uart_console_write(&sport->port, s, count, sbd_console_putchar);
863 /* Restore transmit interrupts and the transmitter enable. */
864 spin_lock_irqsave(&uport->lock, flags);
865 sbd_line_drain(sport);
866 if (sport->tx_stopped)
867 write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS);
868 write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), mask);
869 spin_unlock_irqrestore(&uport->lock, flags);
872 static int __init sbd_console_setup(struct console *co, char *options)
874 int chip = co->index / DUART_MAX_SIDE;
875 int side = co->index % DUART_MAX_SIDE;
876 struct sbd_port *sport = &sbd_duarts[chip].sport[side];
877 struct uart_port *uport = &sport->port;
878 int baud = 115200;
879 int bits = 8;
880 int parity = 'n';
881 int flow = 'n';
882 int ret;
884 if (!sport->duart)
885 return -ENXIO;
887 ret = sbd_map_port(uport);
888 if (ret)
889 return ret;
891 sbd_init_port(sport);
893 if (options)
894 uart_parse_options(options, &baud, &parity, &bits, &flow);
895 return uart_set_options(uport, co, baud, parity, bits, flow);
898 static struct uart_driver sbd_reg;
899 static struct console sbd_console = {
900 .name = "duart",
901 .write = sbd_console_write,
902 .device = uart_console_device,
903 .setup = sbd_console_setup,
904 .flags = CON_PRINTBUFFER,
905 .index = -1,
906 .data = &sbd_reg
909 static int __init sbd_serial_console_init(void)
911 sbd_probe_duarts();
912 register_console(&sbd_console);
914 return 0;
917 console_initcall(sbd_serial_console_init);
919 #define SERIAL_SB1250_DUART_CONSOLE &sbd_console
920 #else
921 #define SERIAL_SB1250_DUART_CONSOLE NULL
922 #endif /* CONFIG_SERIAL_SB1250_DUART_CONSOLE */
925 static struct uart_driver sbd_reg = {
926 .owner = THIS_MODULE,
927 .driver_name = "sb1250_duart",
928 .dev_name = "duart",
929 .major = TTY_MAJOR,
930 .minor = SB1250_DUART_MINOR_BASE,
931 .nr = DUART_MAX_CHIP * DUART_MAX_SIDE,
932 .cons = SERIAL_SB1250_DUART_CONSOLE,
935 /* Set up the driver and register it. */
936 static int __init sbd_init(void)
938 int i, ret;
940 sbd_probe_duarts();
942 ret = uart_register_driver(&sbd_reg);
943 if (ret)
944 return ret;
946 for (i = 0; i < DUART_MAX_CHIP * DUART_MAX_SIDE; i++) {
947 struct sbd_duart *duart = &sbd_duarts[i / DUART_MAX_SIDE];
948 struct sbd_port *sport = &duart->sport[i % DUART_MAX_SIDE];
949 struct uart_port *uport = &sport->port;
951 if (sport->duart)
952 uart_add_one_port(&sbd_reg, uport);
955 return 0;
958 /* Unload the driver. Unregister stuff, get ready to go away. */
959 static void __exit sbd_exit(void)
961 int i;
963 for (i = DUART_MAX_CHIP * DUART_MAX_SIDE - 1; i >= 0; i--) {
964 struct sbd_duart *duart = &sbd_duarts[i / DUART_MAX_SIDE];
965 struct sbd_port *sport = &duart->sport[i % DUART_MAX_SIDE];
966 struct uart_port *uport = &sport->port;
968 if (sport->duart)
969 uart_remove_one_port(&sbd_reg, uport);
972 uart_unregister_driver(&sbd_reg);
975 module_init(sbd_init);
976 module_exit(sbd_exit);