amba.c 18.1 KB
Newer Older
Russell King's avatar
Russell King committed
1
/*
2
 *  linux/drivers/char/amba.c
Russell King's avatar
Russell King committed
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
 *
 *  Driver for AMBA serial ports
 *
 *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
 *
 *  Copyright 1999 ARM Limited
 *  Copyright (C) 2000 Deep Blue Solutions Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
Russell King's avatar
Russell King committed
25
 *  $Id: amba.c,v 1.41 2002/07/28 10:03:27 rmk Exp $
Russell King's avatar
Russell King committed
26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105
 *
 * This is a generic driver for ARM AMBA-type serial ports.  They
 * have a lot of 16550-like features, but are not register compatable.
 * Note that although they do have CTS, DCD and DSR inputs, they do
 * not have an RI input, nor do they have DTR or RTS outputs.  If
 * required, these have to be supplied via some other means (eg, GPIO)
 * and hooked into this driver.
 */
#include <linux/config.h>
#include <linux/module.h>
#include <linux/tty.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/serial.h>
#include <linux/console.h>
#include <linux/sysrq.h>

#include <asm/io.h>
#include <asm/irq.h>

#if defined(CONFIG_SERIAL_AMBA_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif

#include <linux/serial_core.h>

#include <asm/hardware/serial_amba.h>

#define UART_NR		2

#define SERIAL_AMBA_MAJOR	204
#define SERIAL_AMBA_MINOR	16
#define SERIAL_AMBA_NR		UART_NR

#define AMBA_ISR_PASS_LIMIT	256

/*
 * Access macros for the AMBA UARTs
 */
#define UART_GET_INT_STATUS(p)	readb((p)->membase + AMBA_UARTIIR)
#define UART_PUT_ICR(p, c)	writel((c), (p)->membase + AMBA_UARTICR)
#define UART_GET_FR(p)		readb((p)->membase + AMBA_UARTFR)
#define UART_GET_CHAR(p)	readb((p)->membase + AMBA_UARTDR)
#define UART_PUT_CHAR(p, c)	writel((c), (p)->membase + AMBA_UARTDR)
#define UART_GET_RSR(p)		readb((p)->membase + AMBA_UARTRSR)
#define UART_GET_CR(p)		readb((p)->membase + AMBA_UARTCR)
#define UART_PUT_CR(p,c)	writel((c), (p)->membase + AMBA_UARTCR)
#define UART_GET_LCRL(p)	readb((p)->membase + AMBA_UARTLCR_L)
#define UART_PUT_LCRL(p,c)	writel((c), (p)->membase + AMBA_UARTLCR_L)
#define UART_GET_LCRM(p)	readb((p)->membase + AMBA_UARTLCR_M)
#define UART_PUT_LCRM(p,c)	writel((c), (p)->membase + AMBA_UARTLCR_M)
#define UART_GET_LCRH(p)	readb((p)->membase + AMBA_UARTLCR_H)
#define UART_PUT_LCRH(p,c)	writel((c), (p)->membase + AMBA_UARTLCR_H)
#define UART_RX_DATA(s)		(((s) & AMBA_UARTFR_RXFE) == 0)
#define UART_TX_READY(s)	(((s) & AMBA_UARTFR_TXFF) == 0)
#define UART_TX_EMPTY(p)	((UART_GET_FR(p) & AMBA_UARTFR_TMSK) == 0)

#define UART_DUMMY_RSR_RX	256
#define UART_PORT_SIZE		64

/*
 * On the Integrator platform, the port RTS and DTR are provided by
 * bits in the following SC_CTRLS register bits:
 *        RTS  DTR
 *  UART0  7    6
 *  UART1  5    4
 */
#define SC_CTRLC	(IO_ADDRESS(INTEGRATOR_SC_BASE) + INTEGRATOR_SC_CTRLC_OFFSET)
#define SC_CTRLS	(IO_ADDRESS(INTEGRATOR_SC_BASE) + INTEGRATOR_SC_CTRLS_OFFSET)

/*
 * We wrap our port structure around the generic uart_port.
 */
struct uart_amba_port {
	struct uart_port	port;
	unsigned int		dtr_mask;
	unsigned int		rts_mask;
	unsigned int		old_status;
};

106
static void ambauart_stop_tx(struct uart_port *port, unsigned int tty_stop)
Russell King's avatar
Russell King committed
107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154
{
	unsigned int cr;

	cr = UART_GET_CR(port);
	cr &= ~AMBA_UARTCR_TIE;
	UART_PUT_CR(port, cr);
}

static void ambauart_start_tx(struct uart_port *port, unsigned int tty_start)
{
	unsigned int cr;

	cr = UART_GET_CR(port);
	cr |= AMBA_UARTCR_TIE;
	UART_PUT_CR(port, cr);
}

static void ambauart_stop_rx(struct uart_port *port)
{
	unsigned int cr;

	cr = UART_GET_CR(port);
	cr &= ~(AMBA_UARTCR_RIE | AMBA_UARTCR_RTIE);
	UART_PUT_CR(port, cr);
}

static void ambauart_enable_ms(struct uart_port *port)
{
	unsigned int cr;

	cr = UART_GET_CR(port);
	cr |= AMBA_UARTCR_MSIE;
	UART_PUT_CR(port, cr);
}

static void
#ifdef SUPPORT_SYSRQ
ambauart_rx_chars(struct uart_port *port, struct pt_regs *regs)
#else
ambauart_rx_chars(struct uart_port *port)
#endif
{
	struct tty_struct *tty = port->info->tty;
	unsigned int status, ch, rsr, max_count = 256;

	status = UART_GET_FR(port);
	while (UART_RX_DATA(status) && max_count--) {
		if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
Ingo Molnar's avatar
Ingo Molnar committed
155
			tty->flip.work.func((void *)tty);
Russell King's avatar
Russell King committed
156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233
			if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
				printk(KERN_WARNING "TTY_DONT_FLIP set\n");
				return;
			}
		}

		ch = UART_GET_CHAR(port);

		*tty->flip.char_buf_ptr = ch;
		*tty->flip.flag_buf_ptr = TTY_NORMAL;
		port->icount.rx++;

		/*
		 * Note that the error handling code is
		 * out of the main execution path
		 */
		rsr = UART_GET_RSR(port) | UART_DUMMY_RSR_RX;
		if (rsr & AMBA_UARTRSR_ANY) {
			if (rsr & AMBA_UARTRSR_BE) {
				rsr &= ~(AMBA_UARTRSR_FE | AMBA_UARTRSR_PE);
				port->icount.brk++;
				if (uart_handle_break(port))
					goto ignore_char;
			} else if (rsr & AMBA_UARTRSR_PE)
				port->icount.parity++;
			else if (rsr & AMBA_UARTRSR_FE)
				port->icount.frame++;
			if (rsr & AMBA_UARTRSR_OE)
				port->icount.overrun++;

			rsr &= port->read_status_mask;

			if (rsr & AMBA_UARTRSR_BE)
				*tty->flip.flag_buf_ptr = TTY_BREAK;
			else if (rsr & AMBA_UARTRSR_PE)
				*tty->flip.flag_buf_ptr = TTY_PARITY;
			else if (rsr & AMBA_UARTRSR_FE)
				*tty->flip.flag_buf_ptr = TTY_FRAME;
		}

		if (uart_handle_sysrq_char(port, ch, regs))
			goto ignore_char;

		if ((rsr & port->ignore_status_mask) == 0) {
			tty->flip.flag_buf_ptr++;
			tty->flip.char_buf_ptr++;
			tty->flip.count++;
		}
		if ((rsr & AMBA_UARTRSR_OE) &&
		    tty->flip.count < TTY_FLIPBUF_SIZE) {
			/*
			 * Overrun is special, since it's reported
			 * immediately, and doesn't affect the current
			 * character
			 */
			*tty->flip.char_buf_ptr++ = 0;
			*tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
			tty->flip.count++;
		}
	ignore_char:
		status = UART_GET_FR(port);
	}
	tty_flip_buffer_push(tty);
	return;
}

static void ambauart_tx_chars(struct uart_port *port)
{
	struct circ_buf *xmit = &port->info->xmit;
	int count;

	if (port->x_char) {
		UART_PUT_CHAR(port, port->x_char);
		port->icount.tx++;
		port->x_char = 0;
		return;
	}
	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
234
		ambauart_stop_tx(port, 0);
Russell King's avatar
Russell King committed
235 236 237 238 239 240 241 242 243 244 245 246 247
		return;
	}

	count = port->fifosize >> 1;
	do {
		UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
		port->icount.tx++;
		if (uart_circ_empty(xmit))
			break;
	} while (--count > 0);

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
248
		uart_write_wakeup(port);
Russell King's avatar
Russell King committed
249 250

	if (uart_circ_empty(xmit))
251
		ambauart_stop_tx(port, 0);
Russell King's avatar
Russell King committed
252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405
}

static void ambauart_modem_status(struct uart_port *port)
{
	struct uart_amba_port *uap = (struct uart_amba_port *)port;
	unsigned int status, delta;

	UART_PUT_ICR(&uap->port, 0);

	status = UART_GET_FR(&uap->port) & AMBA_UARTFR_MODEM_ANY;

	delta = status ^ uap->old_status;
	uap->old_status = status;

	if (!delta)
		return;

	if (delta & AMBA_UARTFR_DCD)
		uart_handle_dcd_change(&uap->port, status & AMBA_UARTFR_DCD);

	if (delta & AMBA_UARTFR_DSR)
		uap->port.icount.dsr++;

	if (delta & AMBA_UARTFR_CTS)
		uart_handle_cts_change(&uap->port, status & AMBA_UARTFR_CTS);

	wake_up_interruptible(&uap->port.info->delta_msr_wait);
}

static void ambauart_int(int irq, void *dev_id, struct pt_regs *regs)
{
	struct uart_port *port = dev_id;
	unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;

	status = UART_GET_INT_STATUS(port);
	do {
		if (status & (AMBA_UARTIIR_RTIS | AMBA_UARTIIR_RIS))
#ifdef SUPPORT_SYSRQ
			ambauart_rx_chars(port, regs);
#else
			ambauart_rx_chars(port);
#endif
		if (status & AMBA_UARTIIR_MIS)
			ambauart_modem_status(port);
		if (status & AMBA_UARTIIR_TIS)
			ambauart_tx_chars(port);

		if (pass_counter-- == 0)
			break;

		status = UART_GET_INT_STATUS(port);
	} while (status & (AMBA_UARTIIR_RTIS | AMBA_UARTIIR_RIS |
			   AMBA_UARTIIR_TIS));
}

static unsigned int ambauart_tx_empty(struct uart_port *port)
{
	return UART_GET_FR(port) & AMBA_UARTFR_BUSY ? 0 : TIOCSER_TEMT;
}

static unsigned int ambauart_get_mctrl(struct uart_port *port)
{
	unsigned int result = 0;
	unsigned int status;

	status = UART_GET_FR(port);
	if (status & AMBA_UARTFR_DCD)
		result |= TIOCM_CAR;
	if (status & AMBA_UARTFR_DSR)
		result |= TIOCM_DSR;
	if (status & AMBA_UARTFR_CTS)
		result |= TIOCM_CTS;

	return result;
}

static void ambauart_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
	struct uart_amba_port *uap = (struct uart_amba_port *)port;
	unsigned int ctrls = 0, ctrlc = 0;

	if (mctrl & TIOCM_RTS)
		ctrlc |= uap->rts_mask;
	else
		ctrls |= uap->rts_mask;

	if (mctrl & TIOCM_DTR)
		ctrlc |= uap->dtr_mask;
	else
		ctrls |= uap->dtr_mask;

	__raw_writel(ctrls, SC_CTRLS);
	__raw_writel(ctrlc, SC_CTRLC);
}

static void ambauart_break_ctl(struct uart_port *port, int break_state)
{
	unsigned long flags;
	unsigned int lcr_h;

	spin_lock_irqsave(&port->lock, flags);
	lcr_h = UART_GET_LCRH(port);
	if (break_state == -1)
		lcr_h |= AMBA_UARTLCR_H_BRK;
	else
		lcr_h &= ~AMBA_UARTLCR_H_BRK;
	UART_PUT_LCRH(port, lcr_h);
	spin_unlock_irqrestore(&port->lock, flags);
}

static int ambauart_startup(struct uart_port *port)
{
	struct uart_amba_port *uap = (struct uart_amba_port *)port;
	int retval;

	/*
	 * Allocate the IRQ
	 */
	retval = request_irq(port->irq, ambauart_int, 0, "amba", port);
	if (retval)
		return retval;

	/*
	 * initialise the old status of the modem signals
	 */
	uap->old_status = UART_GET_FR(port) & AMBA_UARTFR_MODEM_ANY;

	/*
	 * Finally, enable interrupts
	 */
	UART_PUT_CR(port, AMBA_UARTCR_UARTEN | AMBA_UARTCR_RIE |
			  AMBA_UARTCR_RTIE);

	return 0;
}

static void ambauart_shutdown(struct uart_port *port)
{
	/*
	 * Free the interrupt
	 */
	free_irq(port->irq, port);

	/*
	 * disable all interrupts, disable the port
	 */
	UART_PUT_CR(port, 0);

	/* disable break condition and fifos */
	UART_PUT_LCRH(port, UART_GET_LCRH(port) &
		~(AMBA_UARTLCR_H_BRK | AMBA_UARTLCR_H_FEN));
}

static void
406 407
ambauart_settermios(struct uart_port *port, struct termios *termios,
		    struct termios *old)
Russell King's avatar
Russell King committed
408 409 410
{
	unsigned int lcr_h, old_cr;
	unsigned long flags;
411
	unsigned int quot;
Russell King's avatar
Russell King committed
412

413 414 415 416 417 418
	/*
	 * Ask the core to calculate the divisor for us.
	 */
	quot = uart_get_divisor(port, termios, old);

	switch (termios->c_cflag & CSIZE) {
Russell King's avatar
Russell King committed
419 420 421 422 423 424 425 426 427 428 429 430 431
	case CS5:
		lcr_h = AMBA_UARTLCR_H_WLEN_5;
		break;
	case CS6:
		lcr_h = AMBA_UARTLCR_H_WLEN_6;
		break;
	case CS7:
		lcr_h = AMBA_UARTLCR_H_WLEN_7;
		break;
	default: // CS8
		lcr_h = AMBA_UARTLCR_H_WLEN_8;
		break;
	}
432
	if (termios->c_cflag & CSTOPB)
Russell King's avatar
Russell King committed
433
		lcr_h |= AMBA_UARTLCR_H_STP2;
434
	if (termios->c_cflag & PARENB) {
Russell King's avatar
Russell King committed
435
		lcr_h |= AMBA_UARTLCR_H_PEN;
436
		if (!(termios->c_cflag & PARODD))
Russell King's avatar
Russell King committed
437 438 439 440 441
			lcr_h |= AMBA_UARTLCR_H_EPS;
	}
	if (port->fifosize > 1)
		lcr_h |= AMBA_UARTLCR_H_FEN;

442 443 444 445 446 447 448
	spin_lock_irqsave(&port->lock, flags);

	/*
	 * Update the per-port timeout.
	 */
	uart_update_timeout(port, termios->c_cflag, quot);

Russell King's avatar
Russell King committed
449
	port->read_status_mask = AMBA_UARTRSR_OE;
450
	if (termios->c_iflag & INPCK)
Russell King's avatar
Russell King committed
451
		port->read_status_mask |= AMBA_UARTRSR_FE | AMBA_UARTRSR_PE;
452
	if (termios->c_iflag & (BRKINT | PARMRK))
Russell King's avatar
Russell King committed
453 454 455 456 457 458
		port->read_status_mask |= AMBA_UARTRSR_BE;

	/*
	 * Characters to ignore
	 */
	port->ignore_status_mask = 0;
459
	if (termios->c_iflag & IGNPAR)
Russell King's avatar
Russell King committed
460
		port->ignore_status_mask |= AMBA_UARTRSR_FE | AMBA_UARTRSR_PE;
461
	if (termios->c_iflag & IGNBRK) {
Russell King's avatar
Russell King committed
462 463 464 465 466
		port->ignore_status_mask |= AMBA_UARTRSR_BE;
		/*
		 * If we're ignoring parity and break indicators,
		 * ignore overruns too (for real raw support).
		 */
467
		if (termios->c_iflag & IGNPAR)
Russell King's avatar
Russell King committed
468 469 470 471 472 473
			port->ignore_status_mask |= AMBA_UARTRSR_OE;
	}

	/*
	 * Ignore all characters if CREAD is not set.
	 */
474
	if ((termios->c_cflag & CREAD) == 0)
Russell King's avatar
Russell King committed
475 476 477 478 479
		port->ignore_status_mask |= UART_DUMMY_RSR_RX;

	/* first, disable everything */
	old_cr = UART_GET_CR(port) & ~AMBA_UARTCR_MSIE;

480
	if (UART_ENABLE_MS(port, termios->c_cflag))
Russell King's avatar
Russell King committed
481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549
		old_cr |= AMBA_UARTCR_MSIE;

	UART_PUT_CR(port, 0);

	/* Set baud rate */
	quot -= 1;
	UART_PUT_LCRM(port, ((quot & 0xf00) >> 8));
	UART_PUT_LCRL(port, (quot & 0xff));

	/*
	 * ----------v----------v----------v----------v-----
	 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
	 * ----------^----------^----------^----------^-----
	 */
	UART_PUT_LCRH(port, lcr_h);
	UART_PUT_CR(port, old_cr);

	spin_unlock_irqrestore(&port->lock, flags);
}

static const char *ambauart_type(struct uart_port *port)
{
	return port->type == PORT_AMBA ? "AMBA" : NULL;
}

/*
 * Release the memory region(s) being used by 'port'
 */
static void ambauart_release_port(struct uart_port *port)
{
	release_mem_region(port->mapbase, UART_PORT_SIZE);
}

/*
 * Request the memory region(s) being used by 'port'
 */
static int ambauart_request_port(struct uart_port *port)
{
	return request_mem_region(port->mapbase, UART_PORT_SIZE, "serial_amba")
			!= NULL ? 0 : -EBUSY;
}

/*
 * Configure/autoconfigure the port.
 */
static void ambauart_config_port(struct uart_port *port, int flags)
{
	if (flags & UART_CONFIG_TYPE) {
		port->type = PORT_AMBA;
		ambauart_request_port(port);
	}
}

/*
 * verify the new serial_struct (for TIOCSSERIAL).
 */
static int ambauart_verify_port(struct uart_port *port, struct serial_struct *ser)
{
	int ret = 0;
	if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
		ret = -EINVAL;
	if (ser->irq < 0 || ser->irq >= NR_IRQS)
		ret = -EINVAL;
	if (ser->baud_base < 9600)
		ret = -EINVAL;
	return ret;
}

static struct uart_ops amba_pops = {
550 551 552 553 554 555 556 557 558 559
	.tx_empty	= ambauart_tx_empty,
	.set_mctrl	= ambauart_set_mctrl,
	.get_mctrl	= ambauart_get_mctrl,
	.stop_tx	= ambauart_stop_tx,
	.start_tx	= ambauart_start_tx,
	.stop_rx	= ambauart_stop_rx,
	.enable_ms	= ambauart_enable_ms,
	.break_ctl	= ambauart_break_ctl,
	.startup	= ambauart_startup,
	.shutdown	= ambauart_shutdown,
560
	.settermios	= ambauart_settermios,
561 562 563 564 565
	.type		= ambauart_type,
	.release_port	= ambauart_release_port,
	.request_port	= ambauart_request_port,
	.config_port	= ambauart_config_port,
	.verify_port	= ambauart_verify_port,
Russell King's avatar
Russell King committed
566 567 568 569
};

static struct uart_amba_port amba_ports[UART_NR] = {
	{
570 571 572 573 574 575 576 577 578 579
		.port	= {
			.membase	= (void *)IO_ADDRESS(INTEGRATOR_UART0_BASE),
			.mapbase	= INTEGRATOR_UART0_BASE,
			.iotype		= SERIAL_IO_MEM,
			.irq		= IRQ_UARTINT0,
			.uartclk	= 14745600,
			.fifosize	= 16,
			.ops		= &amba_pops,
			.flags		= ASYNC_BOOT_AUTOCONF,
			.line		= 0,
Russell King's avatar
Russell King committed
580
		},
581 582
		.dtr_mask	= 1 << 5,
		.rts_mask	= 1 << 4,
Russell King's avatar
Russell King committed
583 584
	},
	{
585 586 587 588 589 590 591 592 593 594
		.port	= {
			.membase	= (void *)IO_ADDRESS(INTEGRATOR_UART1_BASE),
			.mapbase	= INTEGRATOR_UART1_BASE,
			.iotype		= SERIAL_IO_MEM,
			.irq		= IRQ_UARTINT1,
			.uartclk	= 14745600,
			.fifosize	= 16,
			.ops		= &amba_pops,
			.flags		= ASYNC_BOOT_AUTOCONF,
			.line		= 1,
Russell King's avatar
Russell King committed
595
		},
596 597
		.dtr_mask	= 1 << 7,
		.rts_mask	= 1 << 6,
Russell King's avatar
Russell King committed
598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698
	}
};

#ifdef CONFIG_SERIAL_AMBA_CONSOLE

static void
ambauart_console_write(struct console *co, const char *s, unsigned int count)
{
	struct uart_port *port = &amba_ports[co->index].port;
	unsigned int status, old_cr;
	int i;

	/*
	 *	First save the CR then disable the interrupts
	 */
	old_cr = UART_GET_CR(port);
	UART_PUT_CR(port, AMBA_UARTCR_UARTEN);

	/*
	 *	Now, do each character
	 */
	for (i = 0; i < count; i++) {
		do {
			status = UART_GET_FR(port);
		} while (!UART_TX_READY(status));
		UART_PUT_CHAR(port, s[i]);
		if (s[i] == '\n') {
			do {
				status = UART_GET_FR(port);
			} while (!UART_TX_READY(status));
			UART_PUT_CHAR(port, '\r');
		}
	}

	/*
	 *	Finally, wait for transmitter to become empty
	 *	and restore the TCR
	 */
	do {
		status = UART_GET_FR(port);
	} while (status & AMBA_UARTFR_BUSY);
	UART_PUT_CR(port, old_cr);
}

static kdev_t ambauart_console_device(struct console *co)
{
	return mk_kdev(SERIAL_AMBA_MAJOR, SERIAL_AMBA_MINOR + co->index);
}

static void __init
ambauart_console_get_options(struct uart_port *port, int *baud,
			     int *parity, int *bits)
{
	if (UART_GET_CR(port) & AMBA_UARTCR_UARTEN) {
		unsigned int lcr_h, quot;
		lcr_h = UART_GET_LCRH(port);

		*parity = 'n';
		if (lcr_h & AMBA_UARTLCR_H_PEN) {
			if (lcr_h & AMBA_UARTLCR_H_EPS)
				*parity = 'e';
			else
				*parity = 'o';
		}

		if ((lcr_h & 0x60) == AMBA_UARTLCR_H_WLEN_7)
			*bits = 7;
		else
			*bits = 8;

		quot = UART_GET_LCRL(port) | UART_GET_LCRM(port) << 8;
		*baud = port->uartclk / (16 * (quot + 1));
	}
}

static int __init ambauart_console_setup(struct console *co, char *options)
{
	struct uart_port *port;
	int baud = 38400;
	int bits = 8;
	int parity = 'n';
	int flow = 'n';

	/*
	 * Check whether an invalid uart number has been specified, and
	 * if so, search for the first available port that does have
	 * console support.
	 */
	if (co->index >= UART_NR)
		co->index = 0;
	port = &amba_ports[co->index].port;

	if (options)
		uart_parse_options(options, &baud, &parity, &bits, &flow);
	else
		ambauart_console_get_options(port, &baud, &parity, &bits);

	return uart_set_options(port, co, baud, parity, bits, flow);
}

static struct console amba_console = {
699 700 701 702 703 704
	.name		= "ttyAM",
	.write		= ambauart_console_write,
	.device		= ambauart_console_device,
	.setup		= ambauart_console_setup,
	.flags		= CON_PRINTBUFFER,
	.index		= -1,
Russell King's avatar
Russell King committed
705 706 707 708 709 710 711 712 713 714 715 716 717
};

void __init ambauart_console_init(void)
{
	register_console(&amba_console);
}

#define AMBA_CONSOLE	&amba_console
#else
#define AMBA_CONSOLE	NULL
#endif

static struct uart_driver amba_reg = {
718 719 720 721 722 723 724
	.owner			= THIS_MODULE,
	.driver_name		= "ttyAM",
	.dev_name		= "ttyAM%d",
	.major			= SERIAL_AMBA_MAJOR,
	.minor			= SERIAL_AMBA_MINOR,
	.nr			= UART_NR,
	.cons			= AMBA_CONSOLE,
Russell King's avatar
Russell King committed
725 726 727 728 729 730
};

static int __init ambauart_init(void)
{
	int ret;

Russell King's avatar
Russell King committed
731
	printk(KERN_INFO "Serial: AMBA driver $Revision: 1.41 $\n");
Russell King's avatar
Russell King committed
732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758

	ret = uart_register_driver(&amba_reg);
	if (ret == 0) {
		int i;

		for (i = 0; i < UART_NR; i++)
			uart_add_one_port(&amba_reg, &amba_ports[i].port);
	}
	return ret;
}

static void __exit ambauart_exit(void)
{
	int i;

	for (i = 0; i < UART_NR; i++)
		uart_remove_one_port(&amba_reg, &amba_ports[i].port);

	uart_unregister_driver(&amba_reg);
}

module_init(ambauart_init);
module_exit(ambauart_exit);

EXPORT_NO_SYMBOLS;

MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
Russell King's avatar
Russell King committed
759
MODULE_DESCRIPTION("ARM AMBA serial port driver $Revision: 1.41 $");
Russell King's avatar
Russell King committed
760
MODULE_LICENSE("GPL");