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v6.8
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Driver for PowerMac Z85c30 based ESCC cell found in the
   4 * "macio" ASICs of various PowerMac models
   5 * 
   6 * Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org)
   7 *
   8 * Derived from drivers/macintosh/macserial.c by Paul Mackerras
   9 * and drivers/serial/sunzilog.c by David S. Miller
  10 *
  11 * Hrm... actually, I ripped most of sunzilog (Thanks David !) and
  12 * adapted special tweaks needed for us. I don't think it's worth
  13 * merging back those though. The DMA code still has to get in
  14 * and once done, I expect that driver to remain fairly stable in
  15 * the long term, unless we change the driver model again...
  16 *
  17 * 2004-08-06 Harald Welte <laforge@gnumonks.org>
  18 *	- Enable BREAK interrupt
  19 *	- Add support for sysreq
  20 *
  21 * TODO:   - Add DMA support
  22 *         - Defer port shutdown to a few seconds after close
  23 *         - maybe put something right into uap->clk_divisor
  24 */
  25
  26#undef DEBUG
 
  27#undef USE_CTRL_O_SYSRQ
  28
  29#include <linux/module.h>
  30#include <linux/tty.h>
  31
  32#include <linux/tty_flip.h>
  33#include <linux/major.h>
  34#include <linux/string.h>
  35#include <linux/fcntl.h>
  36#include <linux/mm.h>
  37#include <linux/kernel.h>
  38#include <linux/delay.h>
  39#include <linux/init.h>
  40#include <linux/console.h>
  41#include <linux/adb.h>
  42#include <linux/pmu.h>
  43#include <linux/bitops.h>
  44#include <linux/sysrq.h>
  45#include <linux/mutex.h>
  46#include <linux/of_address.h>
  47#include <linux/of_irq.h>
  48#include <asm/sections.h>
  49#include <linux/io.h>
  50#include <asm/irq.h>
  51
  52#ifdef CONFIG_PPC_PMAC
 
  53#include <asm/machdep.h>
  54#include <asm/pmac_feature.h>
 
  55#include <asm/macio.h>
  56#else
  57#include <linux/platform_device.h>
  58#define of_machine_is_compatible(x) (0)
  59#endif
  60
  61#include <linux/serial.h>
  62#include <linux/serial_core.h>
  63
  64#include "pmac_zilog.h"
  65
 
 
 
 
  66MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
  67MODULE_DESCRIPTION("Driver for the Mac and PowerMac serial ports.");
  68MODULE_LICENSE("GPL");
  69
  70#ifdef CONFIG_SERIAL_PMACZILOG_TTYS
  71#define PMACZILOG_MAJOR		TTY_MAJOR
  72#define PMACZILOG_MINOR		64
  73#define PMACZILOG_NAME		"ttyS"
  74#else
  75#define PMACZILOG_MAJOR		204
  76#define PMACZILOG_MINOR		192
  77#define PMACZILOG_NAME		"ttyPZ"
  78#endif
  79
  80#define pmz_debug(fmt, arg...)	pr_debug("ttyPZ%d: " fmt, uap->port.line, ## arg)
  81#define pmz_error(fmt, arg...)	pr_err("ttyPZ%d: " fmt, uap->port.line, ## arg)
  82#define pmz_info(fmt, arg...)	pr_info("ttyPZ%d: " fmt, uap->port.line, ## arg)
  83
  84/*
  85 * For the sake of early serial console, we can do a pre-probe
  86 * (optional) of the ports at rather early boot time.
  87 */
  88static struct uart_pmac_port	pmz_ports[MAX_ZS_PORTS];
  89static int			pmz_ports_count;
  90
  91static struct uart_driver pmz_uart_reg = {
  92	.owner		=	THIS_MODULE,
  93	.driver_name	=	PMACZILOG_NAME,
  94	.dev_name	=	PMACZILOG_NAME,
  95	.major		=	PMACZILOG_MAJOR,
  96	.minor		=	PMACZILOG_MINOR,
  97};
  98
  99
 100/* 
 101 * Load all registers to reprogram the port
 102 * This function must only be called when the TX is not busy.  The UART
 103 * port lock must be held and local interrupts disabled.
 104 */
 105static void pmz_load_zsregs(struct uart_pmac_port *uap, u8 *regs)
 106{
 107	int i;
 108
 109	/* Let pending transmits finish.  */
 110	for (i = 0; i < 1000; i++) {
 111		unsigned char stat = read_zsreg(uap, R1);
 112		if (stat & ALL_SNT)
 113			break;
 114		udelay(100);
 115	}
 116
 117	ZS_CLEARERR(uap);
 118	zssync(uap);
 119	ZS_CLEARFIFO(uap);
 120	zssync(uap);
 121	ZS_CLEARERR(uap);
 122
 123	/* Disable all interrupts.  */
 124	write_zsreg(uap, R1,
 125		    regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
 126
 127	/* Set parity, sync config, stop bits, and clock divisor.  */
 128	write_zsreg(uap, R4, regs[R4]);
 129
 130	/* Set misc. TX/RX control bits.  */
 131	write_zsreg(uap, R10, regs[R10]);
 132
 133	/* Set TX/RX controls sans the enable bits.  */
 134	write_zsreg(uap, R3, regs[R3] & ~RxENABLE);
 135	write_zsreg(uap, R5, regs[R5] & ~TxENABLE);
 136
 137	/* now set R7 "prime" on ESCC */
 138	write_zsreg(uap, R15, regs[R15] | EN85C30);
 139	write_zsreg(uap, R7, regs[R7P]);
 140
 141	/* make sure we use R7 "non-prime" on ESCC */
 142	write_zsreg(uap, R15, regs[R15] & ~EN85C30);
 143
 144	/* Synchronous mode config.  */
 145	write_zsreg(uap, R6, regs[R6]);
 146	write_zsreg(uap, R7, regs[R7]);
 147
 148	/* Disable baud generator.  */
 149	write_zsreg(uap, R14, regs[R14] & ~BRENAB);
 150
 151	/* Clock mode control.  */
 152	write_zsreg(uap, R11, regs[R11]);
 153
 154	/* Lower and upper byte of baud rate generator divisor.  */
 155	write_zsreg(uap, R12, regs[R12]);
 156	write_zsreg(uap, R13, regs[R13]);
 157	
 158	/* Now rewrite R14, with BRENAB (if set).  */
 159	write_zsreg(uap, R14, regs[R14]);
 160
 161	/* Reset external status interrupts.  */
 162	write_zsreg(uap, R0, RES_EXT_INT);
 163	write_zsreg(uap, R0, RES_EXT_INT);
 164
 165	/* Rewrite R3/R5, this time without enables masked.  */
 166	write_zsreg(uap, R3, regs[R3]);
 167	write_zsreg(uap, R5, regs[R5]);
 168
 169	/* Rewrite R1, this time without IRQ enabled masked.  */
 170	write_zsreg(uap, R1, regs[R1]);
 171
 172	/* Enable interrupts */
 173	write_zsreg(uap, R9, regs[R9]);
 174}
 175
 176/* 
 177 * We do like sunzilog to avoid disrupting pending Tx
 178 * Reprogram the Zilog channel HW registers with the copies found in the
 179 * software state struct.  If the transmitter is busy, we defer this update
 180 * until the next TX complete interrupt.  Else, we do it right now.
 181 *
 182 * The UART port lock must be held and local interrupts disabled.
 183 */
 184static void pmz_maybe_update_regs(struct uart_pmac_port *uap)
 185{
 186	if (!ZS_REGS_HELD(uap)) {
 187		if (ZS_TX_ACTIVE(uap)) {
 188			uap->flags |= PMACZILOG_FLAG_REGS_HELD;
 189		} else {
 190			pmz_debug("pmz: maybe_update_regs: updating\n");
 191			pmz_load_zsregs(uap, uap->curregs);
 192		}
 193	}
 194}
 195
 196static void pmz_interrupt_control(struct uart_pmac_port *uap, int enable)
 197{
 198	if (enable) {
 199		uap->curregs[1] |= INT_ALL_Rx | TxINT_ENAB;
 200		if (!ZS_IS_EXTCLK(uap))
 201			uap->curregs[1] |= EXT_INT_ENAB;
 202	} else {
 203		uap->curregs[1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
 204	}
 205	write_zsreg(uap, R1, uap->curregs[1]);
 206}
 207
 208static bool pmz_receive_chars(struct uart_pmac_port *uap)
 209	__must_hold(&uap->port.lock)
 210{
 211	struct tty_port *port;
 212	unsigned char ch, r1, drop, flag;
 213	int loops = 0;
 214
 215	/* Sanity check, make sure the old bug is no longer happening */
 216	if (uap->port.state == NULL) {
 217		WARN_ON(1);
 218		(void)read_zsdata(uap);
 219		return false;
 220	}
 221	port = &uap->port.state->port;
 222
 223	while (1) {
 224		drop = 0;
 225
 226		r1 = read_zsreg(uap, R1);
 227		ch = read_zsdata(uap);
 228
 229		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
 230			write_zsreg(uap, R0, ERR_RES);
 231			zssync(uap);
 232		}
 233
 234		ch &= uap->parity_mask;
 235		if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {
 236			uap->flags &= ~PMACZILOG_FLAG_BREAK;
 237		}
 238
 239#if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)
 240#ifdef USE_CTRL_O_SYSRQ
 241		/* Handle the SysRq ^O Hack */
 242		if (ch == '\x0f') {
 243			uap->port.sysrq = jiffies + HZ*5;
 244			goto next_char;
 245		}
 246#endif /* USE_CTRL_O_SYSRQ */
 247		if (uap->port.sysrq) {
 248			int swallow;
 249			uart_port_unlock(&uap->port);
 250			swallow = uart_handle_sysrq_char(&uap->port, ch);
 251			uart_port_lock(&uap->port);
 252			if (swallow)
 253				goto next_char;
 254		}
 255#endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */
 256
 257		/* A real serial line, record the character and status.  */
 258		if (drop)
 259			goto next_char;
 260
 261		flag = TTY_NORMAL;
 262		uap->port.icount.rx++;
 263
 264		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
 265			if (r1 & BRK_ABRT) {
 266				pmz_debug("pmz: got break !\n");
 267				r1 &= ~(PAR_ERR | CRC_ERR);
 268				uap->port.icount.brk++;
 269				if (uart_handle_break(&uap->port))
 270					goto next_char;
 271			}
 272			else if (r1 & PAR_ERR)
 273				uap->port.icount.parity++;
 274			else if (r1 & CRC_ERR)
 275				uap->port.icount.frame++;
 276			if (r1 & Rx_OVR)
 277				uap->port.icount.overrun++;
 278			r1 &= uap->port.read_status_mask;
 279			if (r1 & BRK_ABRT)
 280				flag = TTY_BREAK;
 281			else if (r1 & PAR_ERR)
 282				flag = TTY_PARITY;
 283			else if (r1 & CRC_ERR)
 284				flag = TTY_FRAME;
 285		}
 286
 287		if (uap->port.ignore_status_mask == 0xff ||
 288		    (r1 & uap->port.ignore_status_mask) == 0) {
 289			tty_insert_flip_char(port, ch, flag);
 290		}
 291		if (r1 & Rx_OVR)
 292			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 293	next_char:
 294		/* We can get stuck in an infinite loop getting char 0 when the
 295		 * line is in a wrong HW state, we break that here.
 296		 * When that happens, I disable the receive side of the driver.
 297		 * Note that what I've been experiencing is a real irq loop where
 298		 * I'm getting flooded regardless of the actual port speed.
 299		 * Something strange is going on with the HW
 300		 */
 301		if ((++loops) > 1000)
 302			goto flood;
 303		ch = read_zsreg(uap, R0);
 304		if (!(ch & Rx_CH_AV))
 305			break;
 306	}
 307
 308	return true;
 309 flood:
 310	pmz_interrupt_control(uap, 0);
 311	pmz_error("pmz: rx irq flood !\n");
 312	return true;
 313}
 314
 315static void pmz_status_handle(struct uart_pmac_port *uap)
 316{
 317	unsigned char status;
 318
 319	status = read_zsreg(uap, R0);
 320	write_zsreg(uap, R0, RES_EXT_INT);
 321	zssync(uap);
 322
 323	if (ZS_IS_OPEN(uap) && ZS_WANTS_MODEM_STATUS(uap)) {
 324		if (status & SYNC_HUNT)
 325			uap->port.icount.dsr++;
 326
 327		/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
 328		 * But it does not tell us which bit has changed, we have to keep
 329		 * track of this ourselves.
 330		 * The CTS input is inverted for some reason.  -- paulus
 331		 */
 332		if ((status ^ uap->prev_status) & DCD)
 333			uart_handle_dcd_change(&uap->port,
 334					       (status & DCD));
 335		if ((status ^ uap->prev_status) & CTS)
 336			uart_handle_cts_change(&uap->port,
 337					       !(status & CTS));
 338
 339		wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
 340	}
 341
 342	if (status & BRK_ABRT)
 343		uap->flags |= PMACZILOG_FLAG_BREAK;
 344
 345	uap->prev_status = status;
 346}
 347
 348static void pmz_transmit_chars(struct uart_pmac_port *uap)
 349{
 350	struct circ_buf *xmit;
 351
 352	if (ZS_IS_CONS(uap)) {
 353		unsigned char status = read_zsreg(uap, R0);
 354
 355		/* TX still busy?  Just wait for the next TX done interrupt.
 356		 *
 357		 * It can occur because of how we do serial console writes.  It would
 358		 * be nice to transmit console writes just like we normally would for
 359		 * a TTY line. (ie. buffered and TX interrupt driven).  That is not
 360		 * easy because console writes cannot sleep.  One solution might be
 361		 * to poll on enough port->xmit space becoming free.  -DaveM
 362		 */
 363		if (!(status & Tx_BUF_EMP))
 364			return;
 365	}
 366
 367	uap->flags &= ~PMACZILOG_FLAG_TX_ACTIVE;
 368
 369	if (ZS_REGS_HELD(uap)) {
 370		pmz_load_zsregs(uap, uap->curregs);
 371		uap->flags &= ~PMACZILOG_FLAG_REGS_HELD;
 372	}
 373
 374	if (ZS_TX_STOPPED(uap)) {
 375		uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
 376		goto ack_tx_int;
 377	}
 378
 379	/* Under some circumstances, we see interrupts reported for
 380	 * a closed channel. The interrupt mask in R1 is clear, but
 381	 * R3 still signals the interrupts and we see them when taking
 382	 * an interrupt for the other channel (this could be a qemu
 383	 * bug but since the ESCC doc doesn't specify precsiely whether
 384	 * R3 interrup status bits are masked by R1 interrupt enable
 385	 * bits, better safe than sorry). --BenH.
 386	 */
 387	if (!ZS_IS_OPEN(uap))
 388		goto ack_tx_int;
 389
 390	if (uap->port.x_char) {
 391		uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
 392		write_zsdata(uap, uap->port.x_char);
 393		zssync(uap);
 394		uap->port.icount.tx++;
 395		uap->port.x_char = 0;
 396		return;
 397	}
 398
 399	if (uap->port.state == NULL)
 400		goto ack_tx_int;
 401	xmit = &uap->port.state->xmit;
 402	if (uart_circ_empty(xmit)) {
 403		uart_write_wakeup(&uap->port);
 404		goto ack_tx_int;
 405	}
 406	if (uart_tx_stopped(&uap->port))
 407		goto ack_tx_int;
 408
 409	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
 410	write_zsdata(uap, xmit->buf[xmit->tail]);
 411	zssync(uap);
 412
 413	uart_xmit_advance(&uap->port, 1);
 
 414
 415	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 416		uart_write_wakeup(&uap->port);
 417
 418	return;
 419
 420ack_tx_int:
 421	write_zsreg(uap, R0, RES_Tx_P);
 422	zssync(uap);
 423}
 424
 425/* Hrm... we register that twice, fixme later.... */
 426static irqreturn_t pmz_interrupt(int irq, void *dev_id)
 427{
 428	struct uart_pmac_port *uap = dev_id;
 429	struct uart_pmac_port *uap_a;
 430	struct uart_pmac_port *uap_b;
 431	int rc = IRQ_NONE;
 432	bool push;
 433	u8 r3;
 434
 435	uap_a = pmz_get_port_A(uap);
 436	uap_b = uap_a->mate;
 437
 438	uart_port_lock(&uap_a->port);
 439	r3 = read_zsreg(uap_a, R3);
 440
 
 
 
 441	/* Channel A */
 442	push = false;
 443	if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
 444		if (!ZS_IS_OPEN(uap_a)) {
 445			pmz_debug("ChanA interrupt while not open !\n");
 446			goto skip_a;
 447		}
 448		write_zsreg(uap_a, R0, RES_H_IUS);
 449		zssync(uap_a);		
 450		if (r3 & CHAEXT)
 451			pmz_status_handle(uap_a);
 452		if (r3 & CHARxIP)
 453			push = pmz_receive_chars(uap_a);
 454		if (r3 & CHATxIP)
 455			pmz_transmit_chars(uap_a);
 456		rc = IRQ_HANDLED;
 457	}
 458 skip_a:
 459	uart_port_unlock(&uap_a->port);
 460	if (push)
 461		tty_flip_buffer_push(&uap->port.state->port);
 462
 463	if (!uap_b)
 464		goto out;
 465
 466	uart_port_lock(&uap_b->port);
 467	push = false;
 468	if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
 469		if (!ZS_IS_OPEN(uap_b)) {
 470			pmz_debug("ChanB interrupt while not open !\n");
 471			goto skip_b;
 472		}
 473		write_zsreg(uap_b, R0, RES_H_IUS);
 474		zssync(uap_b);
 475		if (r3 & CHBEXT)
 476			pmz_status_handle(uap_b);
 477		if (r3 & CHBRxIP)
 478			push = pmz_receive_chars(uap_b);
 479		if (r3 & CHBTxIP)
 480			pmz_transmit_chars(uap_b);
 481		rc = IRQ_HANDLED;
 482	}
 483 skip_b:
 484	uart_port_unlock(&uap_b->port);
 485	if (push)
 486		tty_flip_buffer_push(&uap->port.state->port);
 487
 488 out:
 489	return rc;
 490}
 491
 492/*
 493 * Peek the status register, lock not held by caller
 494 */
 495static inline u8 pmz_peek_status(struct uart_pmac_port *uap)
 496{
 497	unsigned long flags;
 498	u8 status;
 499	
 500	uart_port_lock_irqsave(&uap->port, &flags);
 501	status = read_zsreg(uap, R0);
 502	uart_port_unlock_irqrestore(&uap->port, flags);
 503
 504	return status;
 505}
 506
 507/* 
 508 * Check if transmitter is empty
 509 * The port lock is not held.
 510 */
 511static unsigned int pmz_tx_empty(struct uart_port *port)
 512{
 513	unsigned char status;
 514
 515	status = pmz_peek_status(to_pmz(port));
 516	if (status & Tx_BUF_EMP)
 517		return TIOCSER_TEMT;
 518	return 0;
 519}
 520
 521/* 
 522 * Set Modem Control (RTS & DTR) bits
 523 * The port lock is held and interrupts are disabled.
 524 * Note: Shall we really filter out RTS on external ports or
 525 * should that be dealt at higher level only ?
 526 */
 527static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
 528{
 529	struct uart_pmac_port *uap = to_pmz(port);
 530	unsigned char set_bits, clear_bits;
 531
 532        /* Do nothing for irda for now... */
 533	if (ZS_IS_IRDA(uap))
 534		return;
 535	/* We get called during boot with a port not up yet */
 536	if (!(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))
 537		return;
 538
 539	set_bits = clear_bits = 0;
 540
 541	if (ZS_IS_INTMODEM(uap)) {
 542		if (mctrl & TIOCM_RTS)
 543			set_bits |= RTS;
 544		else
 545			clear_bits |= RTS;
 546	}
 547	if (mctrl & TIOCM_DTR)
 548		set_bits |= DTR;
 549	else
 550		clear_bits |= DTR;
 551
 552	/* NOTE: Not subject to 'transmitter active' rule.  */ 
 553	uap->curregs[R5] |= set_bits;
 554	uap->curregs[R5] &= ~clear_bits;
 555
 556	write_zsreg(uap, R5, uap->curregs[R5]);
 557	pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",
 558		  set_bits, clear_bits, uap->curregs[R5]);
 559	zssync(uap);
 560}
 561
 562/* 
 563 * Get Modem Control bits (only the input ones, the core will
 564 * or that with a cached value of the control ones)
 565 * The port lock is held and interrupts are disabled.
 566 */
 567static unsigned int pmz_get_mctrl(struct uart_port *port)
 568{
 569	struct uart_pmac_port *uap = to_pmz(port);
 570	unsigned char status;
 571	unsigned int ret;
 572
 573	status = read_zsreg(uap, R0);
 574
 575	ret = 0;
 576	if (status & DCD)
 577		ret |= TIOCM_CAR;
 578	if (status & SYNC_HUNT)
 579		ret |= TIOCM_DSR;
 580	if (!(status & CTS))
 581		ret |= TIOCM_CTS;
 582
 583	return ret;
 584}
 585
 586/* 
 587 * Stop TX side. Dealt like sunzilog at next Tx interrupt,
 588 * though for DMA, we will have to do a bit more.
 589 * The port lock is held and interrupts are disabled.
 590 */
 591static void pmz_stop_tx(struct uart_port *port)
 592{
 593	to_pmz(port)->flags |= PMACZILOG_FLAG_TX_STOPPED;
 594}
 595
 596/* 
 597 * Kick the Tx side.
 598 * The port lock is held and interrupts are disabled.
 599 */
 600static void pmz_start_tx(struct uart_port *port)
 601{
 602	struct uart_pmac_port *uap = to_pmz(port);
 603	unsigned char status;
 604
 
 
 605	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
 606	uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
 607
 608	status = read_zsreg(uap, R0);
 609
 610	/* TX busy?  Just wait for the TX done interrupt.  */
 611	if (!(status & Tx_BUF_EMP))
 612		return;
 613
 614	/* Send the first character to jump-start the TX done
 615	 * IRQ sending engine.
 616	 */
 617	if (port->x_char) {
 618		write_zsdata(uap, port->x_char);
 619		zssync(uap);
 620		port->icount.tx++;
 621		port->x_char = 0;
 622	} else {
 623		struct circ_buf *xmit = &port->state->xmit;
 624
 625		if (uart_circ_empty(xmit))
 626			return;
 627		write_zsdata(uap, xmit->buf[xmit->tail]);
 628		zssync(uap);
 629		uart_xmit_advance(port, 1);
 
 630
 631		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 632			uart_write_wakeup(&uap->port);
 633	}
 
 
 634}
 635
 636/* 
 637 * Stop Rx side, basically disable emitting of
 638 * Rx interrupts on the port. We don't disable the rx
 639 * side of the chip proper though
 640 * The port lock is held.
 641 */
 642static void pmz_stop_rx(struct uart_port *port)
 643{
 644	struct uart_pmac_port *uap = to_pmz(port);
 645
 
 
 646	/* Disable all RX interrupts.  */
 647	uap->curregs[R1] &= ~RxINT_MASK;
 648	pmz_maybe_update_regs(uap);
 
 
 649}
 650
 651/* 
 652 * Enable modem status change interrupts
 653 * The port lock is held.
 654 */
 655static void pmz_enable_ms(struct uart_port *port)
 656{
 657	struct uart_pmac_port *uap = to_pmz(port);
 658	unsigned char new_reg;
 659
 660	if (ZS_IS_IRDA(uap))
 661		return;
 662	new_reg = uap->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
 663	if (new_reg != uap->curregs[R15]) {
 664		uap->curregs[R15] = new_reg;
 665
 666		/* NOTE: Not subject to 'transmitter active' rule. */
 667		write_zsreg(uap, R15, uap->curregs[R15]);
 668	}
 669}
 670
 671/* 
 672 * Control break state emission
 673 * The port lock is not held.
 674 */
 675static void pmz_break_ctl(struct uart_port *port, int break_state)
 676{
 677	struct uart_pmac_port *uap = to_pmz(port);
 678	unsigned char set_bits, clear_bits, new_reg;
 679	unsigned long flags;
 680
 681	set_bits = clear_bits = 0;
 682
 683	if (break_state)
 684		set_bits |= SND_BRK;
 685	else
 686		clear_bits |= SND_BRK;
 687
 688	uart_port_lock_irqsave(port, &flags);
 689
 690	new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits;
 691	if (new_reg != uap->curregs[R5]) {
 692		uap->curregs[R5] = new_reg;
 693		write_zsreg(uap, R5, uap->curregs[R5]);
 694	}
 695
 696	uart_port_unlock_irqrestore(port, flags);
 697}
 698
 699#ifdef CONFIG_PPC_PMAC
 700
 701/*
 702 * Turn power on or off to the SCC and associated stuff
 703 * (port drivers, modem, IR port, etc.)
 704 * Returns the number of milliseconds we should wait before
 705 * trying to use the port.
 706 */
 707static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
 708{
 709	int delay = 0;
 710	int rc;
 711
 712	if (state) {
 713		rc = pmac_call_feature(
 714			PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);
 715		pmz_debug("port power on result: %d\n", rc);
 716		if (ZS_IS_INTMODEM(uap)) {
 717			rc = pmac_call_feature(
 718				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);
 719			delay = 2500;	/* wait for 2.5s before using */
 720			pmz_debug("modem power result: %d\n", rc);
 721		}
 722	} else {
 723		/* TODO: Make that depend on a timer, don't power down
 724		 * immediately
 725		 */
 726		if (ZS_IS_INTMODEM(uap)) {
 727			rc = pmac_call_feature(
 728				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);
 729			pmz_debug("port power off result: %d\n", rc);
 730		}
 731		pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);
 732	}
 733	return delay;
 734}
 735
 736#else
 737
 738static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
 739{
 740	return 0;
 741}
 742
 743#endif /* !CONFIG_PPC_PMAC */
 744
 745/*
 746 * FixZeroBug....Works around a bug in the SCC receiving channel.
 747 * Inspired from Darwin code, 15 Sept. 2000  -DanM
 748 *
 749 * The following sequence prevents a problem that is seen with O'Hare ASICs
 750 * (most versions -- also with some Heathrow and Hydra ASICs) where a zero
 751 * at the input to the receiver becomes 'stuck' and locks up the receiver.
 752 * This problem can occur as a result of a zero bit at the receiver input
 753 * coincident with any of the following events:
 754 *
 755 *	The SCC is initialized (hardware or software).
 756 *	A framing error is detected.
 757 *	The clocking option changes from synchronous or X1 asynchronous
 758 *		clocking to X16, X32, or X64 asynchronous clocking.
 759 *	The decoding mode is changed among NRZ, NRZI, FM0, or FM1.
 760 *
 761 * This workaround attempts to recover from the lockup condition by placing
 762 * the SCC in synchronous loopback mode with a fast clock before programming
 763 * any of the asynchronous modes.
 764 */
 765static void pmz_fix_zero_bug_scc(struct uart_pmac_port *uap)
 766{
 767	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
 768	zssync(uap);
 769	udelay(10);
 770	write_zsreg(uap, 9, (ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB) | NV);
 771	zssync(uap);
 772
 773	write_zsreg(uap, 4, X1CLK | MONSYNC);
 774	write_zsreg(uap, 3, Rx8);
 775	write_zsreg(uap, 5, Tx8 | RTS);
 776	write_zsreg(uap, 9, NV);	/* Didn't we already do this? */
 777	write_zsreg(uap, 11, RCBR | TCBR);
 778	write_zsreg(uap, 12, 0);
 779	write_zsreg(uap, 13, 0);
 780	write_zsreg(uap, 14, (LOOPBAK | BRSRC));
 781	write_zsreg(uap, 14, (LOOPBAK | BRSRC | BRENAB));
 782	write_zsreg(uap, 3, Rx8 | RxENABLE);
 783	write_zsreg(uap, 0, RES_EXT_INT);
 784	write_zsreg(uap, 0, RES_EXT_INT);
 785	write_zsreg(uap, 0, RES_EXT_INT);	/* to kill some time */
 786
 787	/* The channel should be OK now, but it is probably receiving
 788	 * loopback garbage.
 789	 * Switch to asynchronous mode, disable the receiver,
 790	 * and discard everything in the receive buffer.
 791	 */
 792	write_zsreg(uap, 9, NV);
 793	write_zsreg(uap, 4, X16CLK | SB_MASK);
 794	write_zsreg(uap, 3, Rx8);
 795
 796	while (read_zsreg(uap, 0) & Rx_CH_AV) {
 797		(void)read_zsreg(uap, 8);
 798		write_zsreg(uap, 0, RES_EXT_INT);
 799		write_zsreg(uap, 0, ERR_RES);
 800	}
 801}
 802
 803/*
 804 * Real startup routine, powers up the hardware and sets up
 805 * the SCC. Returns a delay in ms where you need to wait before
 806 * actually using the port, this is typically the internal modem
 807 * powerup delay. This routine expect the lock to be taken.
 808 */
 809static int __pmz_startup(struct uart_pmac_port *uap)
 810{
 811	int pwr_delay = 0;
 812
 813	memset(&uap->curregs, 0, sizeof(uap->curregs));
 814
 815	/* Power up the SCC & underlying hardware (modem/irda) */
 816	pwr_delay = pmz_set_scc_power(uap, 1);
 817
 818	/* Nice buggy HW ... */
 819	pmz_fix_zero_bug_scc(uap);
 820
 821	/* Reset the channel */
 822	uap->curregs[R9] = 0;
 823	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
 824	zssync(uap);
 825	udelay(10);
 826	write_zsreg(uap, 9, 0);
 827	zssync(uap);
 828
 829	/* Clear the interrupt registers */
 830	write_zsreg(uap, R1, 0);
 831	write_zsreg(uap, R0, ERR_RES);
 832	write_zsreg(uap, R0, ERR_RES);
 833	write_zsreg(uap, R0, RES_H_IUS);
 834	write_zsreg(uap, R0, RES_H_IUS);
 835
 836	/* Setup some valid baud rate */
 837	uap->curregs[R4] = X16CLK | SB1;
 838	uap->curregs[R3] = Rx8;
 839	uap->curregs[R5] = Tx8 | RTS;
 840	if (!ZS_IS_IRDA(uap))
 841		uap->curregs[R5] |= DTR;
 842	uap->curregs[R12] = 0;
 843	uap->curregs[R13] = 0;
 844	uap->curregs[R14] = BRENAB;
 845
 846	/* Clear handshaking, enable BREAK interrupts */
 847	uap->curregs[R15] = BRKIE;
 848
 849	/* Master interrupt enable */
 850	uap->curregs[R9] |= NV | MIE;
 851
 852	pmz_load_zsregs(uap, uap->curregs);
 853
 854	/* Enable receiver and transmitter.  */
 855	write_zsreg(uap, R3, uap->curregs[R3] |= RxENABLE);
 856	write_zsreg(uap, R5, uap->curregs[R5] |= TxENABLE);
 857
 858	/* Remember status for DCD/CTS changes */
 859	uap->prev_status = read_zsreg(uap, R0);
 860
 861	return pwr_delay;
 862}
 863
 864static void pmz_irda_reset(struct uart_pmac_port *uap)
 865{
 866	unsigned long flags;
 867
 868	uart_port_lock_irqsave(&uap->port, &flags);
 869	uap->curregs[R5] |= DTR;
 870	write_zsreg(uap, R5, uap->curregs[R5]);
 871	zssync(uap);
 872	uart_port_unlock_irqrestore(&uap->port, flags);
 873	msleep(110);
 874
 875	uart_port_lock_irqsave(&uap->port, &flags);
 876	uap->curregs[R5] &= ~DTR;
 877	write_zsreg(uap, R5, uap->curregs[R5]);
 878	zssync(uap);
 879	uart_port_unlock_irqrestore(&uap->port, flags);
 880	msleep(10);
 881}
 882
 883/*
 884 * This is the "normal" startup routine, using the above one
 885 * wrapped with the lock and doing a schedule delay
 886 */
 887static int pmz_startup(struct uart_port *port)
 888{
 889	struct uart_pmac_port *uap = to_pmz(port);
 890	unsigned long flags;
 891	int pwr_delay = 0;
 892
 
 
 893	uap->flags |= PMACZILOG_FLAG_IS_OPEN;
 894
 895	/* A console is never powered down. Else, power up and
 896	 * initialize the chip
 897	 */
 898	if (!ZS_IS_CONS(uap)) {
 899		uart_port_lock_irqsave(port, &flags);
 900		pwr_delay = __pmz_startup(uap);
 901		uart_port_unlock_irqrestore(port, flags);
 902	}	
 903	sprintf(uap->irq_name, PMACZILOG_NAME"%d", uap->port.line);
 904	if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED,
 905			uap->irq_name, uap)) {
 906		pmz_error("Unable to register zs interrupt handler.\n");
 907		pmz_set_scc_power(uap, 0);
 908		return -ENXIO;
 909	}
 910
 911	/* Right now, we deal with delay by blocking here, I'll be
 912	 * smarter later on
 913	 */
 914	if (pwr_delay != 0) {
 915		pmz_debug("pmz: delaying %d ms\n", pwr_delay);
 916		msleep(pwr_delay);
 917	}
 918
 919	/* IrDA reset is done now */
 920	if (ZS_IS_IRDA(uap))
 921		pmz_irda_reset(uap);
 922
 923	/* Enable interrupt requests for the channel */
 924	uart_port_lock_irqsave(port, &flags);
 925	pmz_interrupt_control(uap, 1);
 926	uart_port_unlock_irqrestore(port, flags);
 
 
 927
 928	return 0;
 929}
 930
 931static void pmz_shutdown(struct uart_port *port)
 932{
 933	struct uart_pmac_port *uap = to_pmz(port);
 934	unsigned long flags;
 935
 936	uart_port_lock_irqsave(port, &flags);
 
 
 937
 938	/* Disable interrupt requests for the channel */
 939	pmz_interrupt_control(uap, 0);
 940
 941	if (!ZS_IS_CONS(uap)) {
 942		/* Disable receiver and transmitter */
 943		uap->curregs[R3] &= ~RxENABLE;
 944		uap->curregs[R5] &= ~TxENABLE;
 945
 946		/* Disable break assertion */
 947		uap->curregs[R5] &= ~SND_BRK;
 948		pmz_maybe_update_regs(uap);
 949	}
 950
 951	uart_port_unlock_irqrestore(port, flags);
 952
 953	/* Release interrupt handler */
 954	free_irq(uap->port.irq, uap);
 955
 956	uart_port_lock_irqsave(port, &flags);
 957
 958	uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;
 959
 960	if (!ZS_IS_CONS(uap))
 961		pmz_set_scc_power(uap, 0);	/* Shut the chip down */
 962
 963	uart_port_unlock_irqrestore(port, flags);
 
 
 964}
 965
 966/* Shared by TTY driver and serial console setup.  The port lock is held
 967 * and local interrupts are disabled.
 968 */
 969static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
 970			      unsigned int iflag, unsigned long baud)
 971{
 972	int brg;
 973
 974	/* Switch to external clocking for IrDA high clock rates. That
 975	 * code could be re-used for Midi interfaces with different
 976	 * multipliers
 977	 */
 978	if (baud >= 115200 && ZS_IS_IRDA(uap)) {
 979		uap->curregs[R4] = X1CLK;
 980		uap->curregs[R11] = RCTRxCP | TCTRxCP;
 981		uap->curregs[R14] = 0; /* BRG off */
 982		uap->curregs[R12] = 0;
 983		uap->curregs[R13] = 0;
 984		uap->flags |= PMACZILOG_FLAG_IS_EXTCLK;
 985	} else {
 986		switch (baud) {
 987		case ZS_CLOCK/16:	/* 230400 */
 988			uap->curregs[R4] = X16CLK;
 989			uap->curregs[R11] = 0;
 990			uap->curregs[R14] = 0;
 991			break;
 992		case ZS_CLOCK/32:	/* 115200 */
 993			uap->curregs[R4] = X32CLK;
 994			uap->curregs[R11] = 0;
 995			uap->curregs[R14] = 0;
 996			break;
 997		default:
 998			uap->curregs[R4] = X16CLK;
 999			uap->curregs[R11] = TCBR | RCBR;
1000			brg = BPS_TO_BRG(baud, ZS_CLOCK / 16);
1001			uap->curregs[R12] = (brg & 255);
1002			uap->curregs[R13] = ((brg >> 8) & 255);
1003			uap->curregs[R14] = BRENAB;
1004		}
1005		uap->flags &= ~PMACZILOG_FLAG_IS_EXTCLK;
1006	}
1007
1008	/* Character size, stop bits, and parity. */
1009	uap->curregs[3] &= ~RxN_MASK;
1010	uap->curregs[5] &= ~TxN_MASK;
1011
1012	switch (cflag & CSIZE) {
1013	case CS5:
1014		uap->curregs[3] |= Rx5;
1015		uap->curregs[5] |= Tx5;
1016		uap->parity_mask = 0x1f;
1017		break;
1018	case CS6:
1019		uap->curregs[3] |= Rx6;
1020		uap->curregs[5] |= Tx6;
1021		uap->parity_mask = 0x3f;
1022		break;
1023	case CS7:
1024		uap->curregs[3] |= Rx7;
1025		uap->curregs[5] |= Tx7;
1026		uap->parity_mask = 0x7f;
1027		break;
1028	case CS8:
1029	default:
1030		uap->curregs[3] |= Rx8;
1031		uap->curregs[5] |= Tx8;
1032		uap->parity_mask = 0xff;
1033		break;
1034	}
1035	uap->curregs[4] &= ~(SB_MASK);
1036	if (cflag & CSTOPB)
1037		uap->curregs[4] |= SB2;
1038	else
1039		uap->curregs[4] |= SB1;
1040	if (cflag & PARENB)
1041		uap->curregs[4] |= PAR_ENAB;
1042	else
1043		uap->curregs[4] &= ~PAR_ENAB;
1044	if (!(cflag & PARODD))
1045		uap->curregs[4] |= PAR_EVEN;
1046	else
1047		uap->curregs[4] &= ~PAR_EVEN;
1048
1049	uap->port.read_status_mask = Rx_OVR;
1050	if (iflag & INPCK)
1051		uap->port.read_status_mask |= CRC_ERR | PAR_ERR;
1052	if (iflag & (IGNBRK | BRKINT | PARMRK))
1053		uap->port.read_status_mask |= BRK_ABRT;
1054
1055	uap->port.ignore_status_mask = 0;
1056	if (iflag & IGNPAR)
1057		uap->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
1058	if (iflag & IGNBRK) {
1059		uap->port.ignore_status_mask |= BRK_ABRT;
1060		if (iflag & IGNPAR)
1061			uap->port.ignore_status_mask |= Rx_OVR;
1062	}
1063
1064	if ((cflag & CREAD) == 0)
1065		uap->port.ignore_status_mask = 0xff;
1066}
1067
1068
1069/*
1070 * Set the irda codec on the imac to the specified baud rate.
1071 */
1072static void pmz_irda_setup(struct uart_pmac_port *uap, unsigned long *baud)
1073{
1074	u8 cmdbyte;
1075	int t, version;
1076
1077	switch (*baud) {
1078	/* SIR modes */
1079	case 2400:
1080		cmdbyte = 0x53;
1081		break;
1082	case 4800:
1083		cmdbyte = 0x52;
1084		break;
1085	case 9600:
1086		cmdbyte = 0x51;
1087		break;
1088	case 19200:
1089		cmdbyte = 0x50;
1090		break;
1091	case 38400:
1092		cmdbyte = 0x4f;
1093		break;
1094	case 57600:
1095		cmdbyte = 0x4e;
1096		break;
1097	case 115200:
1098		cmdbyte = 0x4d;
1099		break;
1100	/* The FIR modes aren't really supported at this point, how
1101	 * do we select the speed ? via the FCR on KeyLargo ?
1102	 */
1103	case 1152000:
1104		cmdbyte = 0;
1105		break;
1106	case 4000000:
1107		cmdbyte = 0;
1108		break;
1109	default: /* 9600 */
1110		cmdbyte = 0x51;
1111		*baud = 9600;
1112		break;
1113	}
1114
1115	/* Wait for transmitter to drain */
1116	t = 10000;
1117	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0
1118	       || (read_zsreg(uap, R1) & ALL_SNT) == 0) {
1119		if (--t <= 0) {
1120			pmz_error("transmitter didn't drain\n");
1121			return;
1122		}
1123		udelay(10);
1124	}
1125
1126	/* Drain the receiver too */
1127	t = 100;
1128	(void)read_zsdata(uap);
1129	(void)read_zsdata(uap);
1130	(void)read_zsdata(uap);
1131	mdelay(10);
1132	while (read_zsreg(uap, R0) & Rx_CH_AV) {
1133		read_zsdata(uap);
1134		mdelay(10);
1135		if (--t <= 0) {
1136			pmz_error("receiver didn't drain\n");
1137			return;
1138		}
1139	}
1140
1141	/* Switch to command mode */
1142	uap->curregs[R5] |= DTR;
1143	write_zsreg(uap, R5, uap->curregs[R5]);
1144	zssync(uap);
1145	mdelay(1);
1146
1147	/* Switch SCC to 19200 */
1148	pmz_convert_to_zs(uap, CS8, 0, 19200);		
1149	pmz_load_zsregs(uap, uap->curregs);
1150	mdelay(1);
1151
1152	/* Write get_version command byte */
1153	write_zsdata(uap, 1);
1154	t = 5000;
1155	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1156		if (--t <= 0) {
1157			pmz_error("irda_setup timed out on get_version byte\n");
1158			goto out;
1159		}
1160		udelay(10);
1161	}
1162	version = read_zsdata(uap);
1163
1164	if (version < 4) {
1165		pmz_info("IrDA: dongle version %d not supported\n", version);
1166		goto out;
1167	}
1168
1169	/* Send speed mode */
1170	write_zsdata(uap, cmdbyte);
1171	t = 5000;
1172	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1173		if (--t <= 0) {
1174			pmz_error("irda_setup timed out on speed mode byte\n");
1175			goto out;
1176		}
1177		udelay(10);
1178	}
1179	t = read_zsdata(uap);
1180	if (t != cmdbyte)
1181		pmz_error("irda_setup speed mode byte = %x (%x)\n", t, cmdbyte);
1182
1183	pmz_info("IrDA setup for %ld bps, dongle version: %d\n",
1184		 *baud, version);
1185
1186	(void)read_zsdata(uap);
1187	(void)read_zsdata(uap);
1188	(void)read_zsdata(uap);
1189
1190 out:
1191	/* Switch back to data mode */
1192	uap->curregs[R5] &= ~DTR;
1193	write_zsreg(uap, R5, uap->curregs[R5]);
1194	zssync(uap);
1195
1196	(void)read_zsdata(uap);
1197	(void)read_zsdata(uap);
1198	(void)read_zsdata(uap);
1199}
1200
1201
1202static void __pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1203			      const struct ktermios *old)
1204{
1205	struct uart_pmac_port *uap = to_pmz(port);
1206	unsigned long baud;
1207
 
 
 
 
1208	/* XXX Check which revs of machines actually allow 1 and 4Mb speeds
1209	 * on the IR dongle. Note that the IRTTY driver currently doesn't know
1210	 * about the FIR mode and high speed modes. So these are unused. For
1211	 * implementing proper support for these, we should probably add some
1212	 * DMA as well, at least on the Rx side, which isn't a simple thing
1213	 * at this point.
1214	 */
1215	if (ZS_IS_IRDA(uap)) {
1216		/* Calc baud rate */
1217		baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);
1218		pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);
1219		/* Cet the irda codec to the right rate */
1220		pmz_irda_setup(uap, &baud);
1221		/* Set final baud rate */
1222		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1223		pmz_load_zsregs(uap, uap->curregs);
1224		zssync(uap);
1225	} else {
1226		baud = uart_get_baud_rate(port, termios, old, 1200, 230400);
1227		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1228		/* Make sure modem status interrupts are correctly configured */
1229		if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {
1230			uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;
1231			uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;
1232		} else {
1233			uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);
1234			uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;
1235		}
1236
1237		/* Load registers to the chip */
1238		pmz_maybe_update_regs(uap);
1239	}
1240	uart_update_timeout(port, termios->c_cflag, baud);
 
 
1241}
1242
1243/* The port lock is not held.  */
1244static void pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1245			    const struct ktermios *old)
1246{
1247	struct uart_pmac_port *uap = to_pmz(port);
1248	unsigned long flags;
1249
1250	uart_port_lock_irqsave(port, &flags);	
1251
1252	/* Disable IRQs on the port */
1253	pmz_interrupt_control(uap, 0);
1254
1255	/* Setup new port configuration */
1256	__pmz_set_termios(port, termios, old);
1257
1258	/* Re-enable IRQs on the port */
1259	if (ZS_IS_OPEN(uap))
1260		pmz_interrupt_control(uap, 1);
1261
1262	uart_port_unlock_irqrestore(port, flags);
1263}
1264
1265static const char *pmz_type(struct uart_port *port)
1266{
1267	struct uart_pmac_port *uap = to_pmz(port);
1268
1269	if (ZS_IS_IRDA(uap))
1270		return "Z85c30 ESCC - Infrared port";
1271	else if (ZS_IS_INTMODEM(uap))
1272		return "Z85c30 ESCC - Internal modem";
1273	return "Z85c30 ESCC - Serial port";
1274}
1275
1276/* We do not request/release mappings of the registers here, this
1277 * happens at early serial probe time.
1278 */
1279static void pmz_release_port(struct uart_port *port)
1280{
1281}
1282
1283static int pmz_request_port(struct uart_port *port)
1284{
1285	return 0;
1286}
1287
1288/* These do not need to do anything interesting either.  */
1289static void pmz_config_port(struct uart_port *port, int flags)
1290{
1291}
1292
1293/* We do not support letting the user mess with the divisor, IRQ, etc. */
1294static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)
1295{
1296	return -EINVAL;
1297}
1298
1299#ifdef CONFIG_CONSOLE_POLL
1300
1301static int pmz_poll_get_char(struct uart_port *port)
1302{
1303	struct uart_pmac_port *uap =
1304		container_of(port, struct uart_pmac_port, port);
1305	int tries = 2;
1306
1307	while (tries) {
1308		if ((read_zsreg(uap, R0) & Rx_CH_AV) != 0)
1309			return read_zsdata(uap);
1310		if (tries--)
1311			udelay(5);
1312	}
1313
1314	return NO_POLL_CHAR;
1315}
1316
1317static void pmz_poll_put_char(struct uart_port *port, unsigned char c)
1318{
1319	struct uart_pmac_port *uap =
1320		container_of(port, struct uart_pmac_port, port);
1321
1322	/* Wait for the transmit buffer to empty. */
1323	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1324		udelay(5);
1325	write_zsdata(uap, c);
1326}
1327
1328#endif /* CONFIG_CONSOLE_POLL */
1329
1330static const struct uart_ops pmz_pops = {
1331	.tx_empty	=	pmz_tx_empty,
1332	.set_mctrl	=	pmz_set_mctrl,
1333	.get_mctrl	=	pmz_get_mctrl,
1334	.stop_tx	=	pmz_stop_tx,
1335	.start_tx	=	pmz_start_tx,
1336	.stop_rx	=	pmz_stop_rx,
1337	.enable_ms	=	pmz_enable_ms,
1338	.break_ctl	=	pmz_break_ctl,
1339	.startup	=	pmz_startup,
1340	.shutdown	=	pmz_shutdown,
1341	.set_termios	=	pmz_set_termios,
1342	.type		=	pmz_type,
1343	.release_port	=	pmz_release_port,
1344	.request_port	=	pmz_request_port,
1345	.config_port	=	pmz_config_port,
1346	.verify_port	=	pmz_verify_port,
1347#ifdef CONFIG_CONSOLE_POLL
1348	.poll_get_char	=	pmz_poll_get_char,
1349	.poll_put_char	=	pmz_poll_put_char,
1350#endif
1351};
1352
1353#ifdef CONFIG_PPC_PMAC
1354
1355/*
1356 * Setup one port structure after probing, HW is down at this point,
1357 * Unlike sunzilog, we don't need to pre-init the spinlock as we don't
1358 * register our console before uart_add_one_port() is called
1359 */
1360static int __init pmz_init_port(struct uart_pmac_port *uap)
1361{
1362	struct device_node *np = uap->node;
1363	const char *conn;
1364	const struct slot_names_prop {
1365		int	count;
1366		char	name[1];
1367	} *slots;
1368	int len;
1369	struct resource r_ports;
1370
1371	/*
1372	 * Request & map chip registers
1373	 */
1374	if (of_address_to_resource(np, 0, &r_ports))
1375		return -ENODEV;
1376	uap->port.mapbase = r_ports.start;
1377	uap->port.membase = ioremap(uap->port.mapbase, 0x1000);
1378
1379	uap->control_reg = uap->port.membase;
1380	uap->data_reg = uap->control_reg + 0x10;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1381
1382	/*
1383	 * Detect port type
1384	 */
1385	if (of_device_is_compatible(np, "cobalt"))
1386		uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1387	conn = of_get_property(np, "AAPL,connector", &len);
1388	if (conn && (strcmp(conn, "infrared") == 0))
1389		uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1390	uap->port_type = PMAC_SCC_ASYNC;
1391	/* 1999 Powerbook G3 has slot-names property instead */
1392	slots = of_get_property(np, "slot-names", &len);
1393	if (slots && slots->count > 0) {
1394		if (strcmp(slots->name, "IrDA") == 0)
1395			uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1396		else if (strcmp(slots->name, "Modem") == 0)
1397			uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1398	}
1399	if (ZS_IS_IRDA(uap))
1400		uap->port_type = PMAC_SCC_IRDA;
1401	if (ZS_IS_INTMODEM(uap)) {
1402		struct device_node* i2c_modem =
1403			of_find_node_by_name(NULL, "i2c-modem");
1404		if (i2c_modem) {
1405			const char* mid =
1406				of_get_property(i2c_modem, "modem-id", NULL);
1407			if (mid) switch(*mid) {
1408			case 0x04 :
1409			case 0x05 :
1410			case 0x07 :
1411			case 0x08 :
1412			case 0x0b :
1413			case 0x0c :
1414				uap->port_type = PMAC_SCC_I2S1;
1415			}
1416			printk(KERN_INFO "pmac_zilog: i2c-modem detected, id: %d\n",
1417				mid ? (*mid) : 0);
1418			of_node_put(i2c_modem);
1419		} else {
1420			printk(KERN_INFO "pmac_zilog: serial modem detected\n");
1421		}
1422	}
1423
1424	/*
1425	 * Init remaining bits of "port" structure
1426	 */
1427	uap->port.iotype = UPIO_MEM;
1428	uap->port.irq = irq_of_parse_and_map(np, 0);
1429	uap->port.uartclk = ZS_CLOCK;
1430	uap->port.fifosize = 1;
1431	uap->port.ops = &pmz_pops;
1432	uap->port.type = PORT_PMAC_ZILOG;
1433	uap->port.flags = 0;
1434
1435	/*
1436	 * Fixup for the port on Gatwick for which the device-tree has
1437	 * missing interrupts. Normally, the macio_dev would contain
1438	 * fixed up interrupt info, but we use the device-tree directly
1439	 * here due to early probing so we need the fixup too.
1440	 */
1441	if (uap->port.irq == 0 &&
1442	    np->parent && np->parent->parent &&
1443	    of_device_is_compatible(np->parent->parent, "gatwick")) {
1444		/* IRQs on gatwick are offset by 64 */
1445		uap->port.irq = irq_create_mapping(NULL, 64 + 15);
 
 
1446	}
1447
1448	/* Setup some valid baud rate information in the register
1449	 * shadows so we don't write crap there before baud rate is
1450	 * first initialized.
1451	 */
1452	pmz_convert_to_zs(uap, CS8, 0, 9600);
1453
1454	return 0;
1455}
1456
1457/*
1458 * Get rid of a port on module removal
1459 */
1460static void pmz_dispose_port(struct uart_pmac_port *uap)
1461{
1462	struct device_node *np;
1463
1464	np = uap->node;
 
 
1465	iounmap(uap->control_reg);
1466	uap->node = NULL;
1467	of_node_put(np);
1468	memset(uap, 0, sizeof(struct uart_pmac_port));
1469}
1470
1471/*
1472 * Called upon match with an escc node in the device-tree.
1473 */
1474static int pmz_attach(struct macio_dev *mdev, const struct of_device_id *match)
1475{
1476	struct uart_pmac_port *uap;
1477	int i;
1478	
1479	/* Iterate the pmz_ports array to find a matching entry
1480	 */
1481	for (i = 0; i < MAX_ZS_PORTS; i++)
1482		if (pmz_ports[i].node == mdev->ofdev.dev.of_node)
1483			break;
1484	if (i >= MAX_ZS_PORTS)
1485		return -ENODEV;
1486
1487
1488	uap = &pmz_ports[i];
1489	uap->dev = mdev;
1490	uap->port.dev = &mdev->ofdev.dev;
1491	dev_set_drvdata(&mdev->ofdev.dev, uap);
1492
1493	/* We still activate the port even when failing to request resources
1494	 * to work around bugs in ancient Apple device-trees
1495	 */
1496	if (macio_request_resources(uap->dev, "pmac_zilog"))
1497		printk(KERN_WARNING "%pOFn: Failed to request resource"
1498		       ", port still active\n",
1499		       uap->node);
1500	else
1501		uap->flags |= PMACZILOG_FLAG_RSRC_REQUESTED;
1502
1503	return uart_add_one_port(&pmz_uart_reg, &uap->port);
1504}
1505
1506/*
1507 * That one should not be called, macio isn't really a hotswap device,
1508 * we don't expect one of those serial ports to go away...
1509 */
1510static int pmz_detach(struct macio_dev *mdev)
1511{
1512	struct uart_pmac_port	*uap = dev_get_drvdata(&mdev->ofdev.dev);
1513	
1514	if (!uap)
1515		return -ENODEV;
1516
1517	uart_remove_one_port(&pmz_uart_reg, &uap->port);
1518
1519	if (uap->flags & PMACZILOG_FLAG_RSRC_REQUESTED) {
1520		macio_release_resources(uap->dev);
1521		uap->flags &= ~PMACZILOG_FLAG_RSRC_REQUESTED;
1522	}
1523	dev_set_drvdata(&mdev->ofdev.dev, NULL);
1524	uap->dev = NULL;
1525	uap->port.dev = NULL;
1526	
1527	return 0;
1528}
1529
1530
1531static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
1532{
1533	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1534
1535	if (uap == NULL) {
1536		printk("HRM... pmz_suspend with NULL uap\n");
1537		return 0;
1538	}
1539
1540	uart_suspend_port(&pmz_uart_reg, &uap->port);
1541
1542	return 0;
1543}
1544
1545
1546static int pmz_resume(struct macio_dev *mdev)
1547{
1548	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1549
1550	if (uap == NULL)
1551		return 0;
1552
1553	uart_resume_port(&pmz_uart_reg, &uap->port);
1554
1555	return 0;
1556}
1557
1558/*
1559 * Probe all ports in the system and build the ports array, we register
1560 * with the serial layer later, so we get a proper struct device which
1561 * allows the tty to attach properly. This is later than it used to be
1562 * but the tty layer really wants it that way.
1563 */
1564static int __init pmz_probe(void)
1565{
1566	struct device_node	*node_p, *node_a, *node_b, *np;
1567	int			count = 0;
1568	int			rc;
1569
1570	/*
1571	 * Find all escc chips in the system
1572	 */
1573	for_each_node_by_name(node_p, "escc") {
1574		/*
1575		 * First get channel A/B node pointers
1576		 * 
1577		 * TODO: Add routines with proper locking to do that...
1578		 */
1579		node_a = node_b = NULL;
1580		for_each_child_of_node(node_p, np) {
1581			if (of_node_name_prefix(np, "ch-a"))
1582				node_a = of_node_get(np);
1583			else if (of_node_name_prefix(np, "ch-b"))
1584				node_b = of_node_get(np);
1585		}
1586		if (!node_a && !node_b) {
1587			of_node_put(node_a);
1588			of_node_put(node_b);
1589			printk(KERN_ERR "pmac_zilog: missing node %c for escc %pOF\n",
1590				(!node_a) ? 'a' : 'b', node_p);
1591			continue;
1592		}
1593
1594		/*
1595		 * Fill basic fields in the port structures
1596		 */
1597		if (node_b != NULL) {
1598			pmz_ports[count].mate		= &pmz_ports[count+1];
1599			pmz_ports[count+1].mate		= &pmz_ports[count];
1600		}
1601		pmz_ports[count].flags		= PMACZILOG_FLAG_IS_CHANNEL_A;
1602		pmz_ports[count].node		= node_a;
1603		pmz_ports[count+1].node		= node_b;
1604		pmz_ports[count].port.line	= count;
1605		pmz_ports[count+1].port.line	= count+1;
1606
1607		/*
1608		 * Setup the ports for real
1609		 */
1610		rc = pmz_init_port(&pmz_ports[count]);
1611		if (rc == 0 && node_b != NULL)
1612			rc = pmz_init_port(&pmz_ports[count+1]);
1613		if (rc != 0) {
1614			of_node_put(node_a);
1615			of_node_put(node_b);
1616			memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));
1617			memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));
1618			continue;
1619		}
1620		count += 2;
1621	}
1622	pmz_ports_count = count;
1623
1624	return 0;
1625}
1626
1627#else
1628
1629/* On PCI PowerMacs, pmz_probe() does an explicit search of the OpenFirmware
1630 * tree to obtain the device_nodes needed to start the console before the
1631 * macio driver. On Macs without OpenFirmware, global platform_devices take
1632 * the place of those device_nodes.
1633 */
1634extern struct platform_device scc_a_pdev, scc_b_pdev;
1635
1636static int __init pmz_init_port(struct uart_pmac_port *uap)
1637{
1638	struct resource *r_ports;
1639	int irq;
1640
1641	r_ports = platform_get_resource(uap->pdev, IORESOURCE_MEM, 0);
1642	if (!r_ports)
 
1643		return -ENODEV;
1644
1645	irq = platform_get_irq(uap->pdev, 0);
1646	if (irq < 0)
1647		return irq;
1648
1649	uap->port.mapbase  = r_ports->start;
1650	uap->port.membase  = (unsigned char __iomem *) r_ports->start;
1651	uap->port.iotype   = UPIO_MEM;
1652	uap->port.irq      = irq;
1653	uap->port.uartclk  = ZS_CLOCK;
1654	uap->port.fifosize = 1;
1655	uap->port.ops      = &pmz_pops;
1656	uap->port.type     = PORT_PMAC_ZILOG;
1657	uap->port.flags    = 0;
1658
1659	uap->control_reg   = uap->port.membase;
1660	uap->data_reg      = uap->control_reg + 4;
1661	uap->port_type     = 0;
1662	uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_PMACZILOG_CONSOLE);
1663
1664	pmz_convert_to_zs(uap, CS8, 0, 9600);
1665
1666	return 0;
1667}
1668
1669static int __init pmz_probe(void)
1670{
1671	int err;
1672
1673	pmz_ports_count = 0;
1674
1675	pmz_ports[0].port.line = 0;
1676	pmz_ports[0].flags     = PMACZILOG_FLAG_IS_CHANNEL_A;
1677	pmz_ports[0].pdev      = &scc_a_pdev;
1678	err = pmz_init_port(&pmz_ports[0]);
1679	if (err)
1680		return err;
1681	pmz_ports_count++;
1682
1683	pmz_ports[0].mate      = &pmz_ports[1];
1684	pmz_ports[1].mate      = &pmz_ports[0];
1685	pmz_ports[1].port.line = 1;
1686	pmz_ports[1].flags     = 0;
1687	pmz_ports[1].pdev      = &scc_b_pdev;
1688	err = pmz_init_port(&pmz_ports[1]);
1689	if (err)
1690		return err;
1691	pmz_ports_count++;
1692
1693	return 0;
1694}
1695
1696static void pmz_dispose_port(struct uart_pmac_port *uap)
1697{
1698	memset(uap, 0, sizeof(struct uart_pmac_port));
1699}
1700
1701static int __init pmz_attach(struct platform_device *pdev)
1702{
1703	struct uart_pmac_port *uap;
1704	int i;
1705
1706	/* Iterate the pmz_ports array to find a matching entry */
1707	for (i = 0; i < pmz_ports_count; i++)
1708		if (pmz_ports[i].pdev == pdev)
1709			break;
1710	if (i >= pmz_ports_count)
1711		return -ENODEV;
1712
1713	uap = &pmz_ports[i];
1714	uap->port.dev = &pdev->dev;
1715	platform_set_drvdata(pdev, uap);
1716
1717	return uart_add_one_port(&pmz_uart_reg, &uap->port);
1718}
1719
1720static int __exit pmz_detach(struct platform_device *pdev)
1721{
1722	struct uart_pmac_port *uap = platform_get_drvdata(pdev);
1723
1724	if (!uap)
1725		return -ENODEV;
1726
1727	uart_remove_one_port(&pmz_uart_reg, &uap->port);
1728
1729	uap->port.dev = NULL;
1730
1731	return 0;
1732}
1733
1734#endif /* !CONFIG_PPC_PMAC */
1735
1736#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1737
1738static void pmz_console_write(struct console *con, const char *s, unsigned int count);
1739static int __init pmz_console_setup(struct console *co, char *options);
1740
1741static struct console pmz_console = {
1742	.name	=	PMACZILOG_NAME,
1743	.write	=	pmz_console_write,
1744	.device	=	uart_console_device,
1745	.setup	=	pmz_console_setup,
1746	.flags	=	CON_PRINTBUFFER,
1747	.index	=	-1,
1748	.data   =	&pmz_uart_reg,
1749};
1750
1751#define PMACZILOG_CONSOLE	&pmz_console
1752#else /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1753#define PMACZILOG_CONSOLE	(NULL)
1754#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1755
1756/*
1757 * Register the driver, console driver and ports with the serial
1758 * core
1759 */
1760static int __init pmz_register(void)
1761{
1762	pmz_uart_reg.nr = pmz_ports_count;
1763	pmz_uart_reg.cons = PMACZILOG_CONSOLE;
1764
1765	/*
1766	 * Register this driver with the serial core
1767	 */
1768	return uart_register_driver(&pmz_uart_reg);
1769}
1770
1771#ifdef CONFIG_PPC_PMAC
1772
1773static const struct of_device_id pmz_match[] =
1774{
1775	{
1776	.name		= "ch-a",
1777	},
1778	{
1779	.name		= "ch-b",
1780	},
1781	{},
1782};
1783MODULE_DEVICE_TABLE (of, pmz_match);
1784
1785static struct macio_driver pmz_driver = {
1786	.driver = {
1787		.name 		= "pmac_zilog",
1788		.owner		= THIS_MODULE,
1789		.of_match_table	= pmz_match,
1790	},
1791	.probe		= pmz_attach,
1792	.remove		= pmz_detach,
1793	.suspend	= pmz_suspend,
1794	.resume		= pmz_resume,
1795};
1796
1797#else
1798
1799static struct platform_driver pmz_driver = {
1800	.remove		= __exit_p(pmz_detach),
1801	.driver		= {
1802		.name		= "scc",
1803	},
1804};
1805
1806#endif /* !CONFIG_PPC_PMAC */
1807
1808static int __init init_pmz(void)
1809{
1810	int rc, i;
 
1811
1812	/* 
1813	 * First, we need to do a direct OF-based probe pass. We
1814	 * do that because we want serial console up before the
1815	 * macio stuffs calls us back, and since that makes it
1816	 * easier to pass the proper number of channels to
1817	 * uart_register_driver()
1818	 */
1819	if (pmz_ports_count == 0)
1820		pmz_probe();
1821
1822	/*
1823	 * Bail early if no port found
1824	 */
1825	if (pmz_ports_count == 0)
1826		return -ENODEV;
1827
1828	/*
1829	 * Now we register with the serial layer
1830	 */
1831	rc = pmz_register();
1832	if (rc) {
1833		printk(KERN_ERR 
1834			"pmac_zilog: Error registering serial device, disabling pmac_zilog.\n"
1835		 	"pmac_zilog: Did another serial driver already claim the minors?\n"); 
1836		/* effectively "pmz_unprobe()" */
1837		for (i=0; i < pmz_ports_count; i++)
1838			pmz_dispose_port(&pmz_ports[i]);
1839		return rc;
1840	}
1841
1842	/*
1843	 * Then we register the macio driver itself
1844	 */
1845#ifdef CONFIG_PPC_PMAC
1846	return macio_register_driver(&pmz_driver);
1847#else
1848	return platform_driver_probe(&pmz_driver, pmz_attach);
1849#endif
1850}
1851
1852static void __exit exit_pmz(void)
1853{
1854	int i;
1855
1856#ifdef CONFIG_PPC_PMAC
1857	/* Get rid of macio-driver (detach from macio) */
1858	macio_unregister_driver(&pmz_driver);
1859#else
1860	platform_driver_unregister(&pmz_driver);
1861#endif
1862
1863	for (i = 0; i < pmz_ports_count; i++) {
1864		struct uart_pmac_port *uport = &pmz_ports[i];
1865#ifdef CONFIG_PPC_PMAC
1866		if (uport->node != NULL)
1867			pmz_dispose_port(uport);
1868#else
1869		if (uport->pdev != NULL)
1870			pmz_dispose_port(uport);
1871#endif
1872	}
1873	/* Unregister UART driver */
1874	uart_unregister_driver(&pmz_uart_reg);
1875}
1876
1877#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1878
1879static void pmz_console_putchar(struct uart_port *port, unsigned char ch)
1880{
1881	struct uart_pmac_port *uap =
1882		container_of(port, struct uart_pmac_port, port);
1883
1884	/* Wait for the transmit buffer to empty. */
1885	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1886		udelay(5);
1887	write_zsdata(uap, ch);
1888}
1889
1890/*
1891 * Print a string to the serial port trying not to disturb
1892 * any possible real use of the port...
1893 */
1894static void pmz_console_write(struct console *con, const char *s, unsigned int count)
1895{
1896	struct uart_pmac_port *uap = &pmz_ports[con->index];
1897	unsigned long flags;
1898
1899	uart_port_lock_irqsave(&uap->port, &flags);
1900
1901	/* Turn of interrupts and enable the transmitter. */
1902	write_zsreg(uap, R1, uap->curregs[1] & ~TxINT_ENAB);
1903	write_zsreg(uap, R5, uap->curregs[5] | TxENABLE | RTS | DTR);
1904
1905	uart_console_write(&uap->port, s, count, pmz_console_putchar);
1906
1907	/* Restore the values in the registers. */
1908	write_zsreg(uap, R1, uap->curregs[1]);
1909	/* Don't disable the transmitter. */
1910
1911	uart_port_unlock_irqrestore(&uap->port, flags);
1912}
1913
1914/*
1915 * Setup the serial console
1916 */
1917static int __init pmz_console_setup(struct console *co, char *options)
1918{
1919	struct uart_pmac_port *uap;
1920	struct uart_port *port;
1921	int baud = 38400;
1922	int bits = 8;
1923	int parity = 'n';
1924	int flow = 'n';
1925	unsigned long pwr_delay;
1926
1927	/*
1928	 * XServe's default to 57600 bps
1929	 */
1930	if (of_machine_is_compatible("RackMac1,1")
1931	    || of_machine_is_compatible("RackMac1,2")
1932	    || of_machine_is_compatible("MacRISC4"))
1933		baud = 57600;
1934
1935	/*
1936	 * Check whether an invalid uart number has been specified, and
1937	 * if so, search for the first available port that does have
1938	 * console support.
1939	 */
1940	if (co->index >= pmz_ports_count)
1941		co->index = 0;
1942	uap = &pmz_ports[co->index];
1943#ifdef CONFIG_PPC_PMAC
1944	if (uap->node == NULL)
1945		return -ENODEV;
1946#else
1947	if (uap->pdev == NULL)
1948		return -ENODEV;
1949#endif
1950	port = &uap->port;
1951
1952	/*
1953	 * Mark port as beeing a console
1954	 */
1955	uap->flags |= PMACZILOG_FLAG_IS_CONS;
1956
1957	/*
1958	 * Temporary fix for uart layer who didn't setup the spinlock yet
1959	 */
1960	spin_lock_init(&port->lock);
1961
1962	/*
1963	 * Enable the hardware
1964	 */
1965	pwr_delay = __pmz_startup(uap);
1966	if (pwr_delay)
1967		mdelay(pwr_delay);
1968	
1969	if (options)
1970		uart_parse_options(options, &baud, &parity, &bits, &flow);
1971
1972	return uart_set_options(port, co, baud, parity, bits, flow);
1973}
1974
1975static int __init pmz_console_init(void)
1976{
1977	/* Probe ports */
1978	pmz_probe();
1979
1980	if (pmz_ports_count == 0)
1981		return -ENODEV;
1982
1983	/* TODO: Autoprobe console based on OF */
1984	/* pmz_console.index = i; */
1985	register_console(&pmz_console);
1986
1987	return 0;
1988
1989}
1990console_initcall(pmz_console_init);
1991#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1992
1993module_init(init_pmz);
1994module_exit(exit_pmz);
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Driver for PowerMac Z85c30 based ESCC cell found in the
   4 * "macio" ASICs of various PowerMac models
   5 * 
   6 * Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org)
   7 *
   8 * Derived from drivers/macintosh/macserial.c by Paul Mackerras
   9 * and drivers/serial/sunzilog.c by David S. Miller
  10 *
  11 * Hrm... actually, I ripped most of sunzilog (Thanks David !) and
  12 * adapted special tweaks needed for us. I don't think it's worth
  13 * merging back those though. The DMA code still has to get in
  14 * and once done, I expect that driver to remain fairly stable in
  15 * the long term, unless we change the driver model again...
  16 *
  17 * 2004-08-06 Harald Welte <laforge@gnumonks.org>
  18 *	- Enable BREAK interrupt
  19 *	- Add support for sysreq
  20 *
  21 * TODO:   - Add DMA support
  22 *         - Defer port shutdown to a few seconds after close
  23 *         - maybe put something right into uap->clk_divisor
  24 */
  25
  26#undef DEBUG
  27#undef DEBUG_HARD
  28#undef USE_CTRL_O_SYSRQ
  29
  30#include <linux/module.h>
  31#include <linux/tty.h>
  32
  33#include <linux/tty_flip.h>
  34#include <linux/major.h>
  35#include <linux/string.h>
  36#include <linux/fcntl.h>
  37#include <linux/mm.h>
  38#include <linux/kernel.h>
  39#include <linux/delay.h>
  40#include <linux/init.h>
  41#include <linux/console.h>
  42#include <linux/adb.h>
  43#include <linux/pmu.h>
  44#include <linux/bitops.h>
  45#include <linux/sysrq.h>
  46#include <linux/mutex.h>
  47#include <linux/of_address.h>
  48#include <linux/of_irq.h>
  49#include <asm/sections.h>
  50#include <linux/io.h>
  51#include <asm/irq.h>
  52
  53#ifdef CONFIG_PPC_PMAC
  54#include <asm/prom.h>
  55#include <asm/machdep.h>
  56#include <asm/pmac_feature.h>
  57#include <asm/dbdma.h>
  58#include <asm/macio.h>
  59#else
  60#include <linux/platform_device.h>
  61#define of_machine_is_compatible(x) (0)
  62#endif
  63
  64#include <linux/serial.h>
  65#include <linux/serial_core.h>
  66
  67#include "pmac_zilog.h"
  68
  69/* Not yet implemented */
  70#undef HAS_DBDMA
  71
  72static char version[] __initdata = "pmac_zilog: 0.6 (Benjamin Herrenschmidt <benh@kernel.crashing.org>)";
  73MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
  74MODULE_DESCRIPTION("Driver for the Mac and PowerMac serial ports.");
  75MODULE_LICENSE("GPL");
  76
  77#ifdef CONFIG_SERIAL_PMACZILOG_TTYS
  78#define PMACZILOG_MAJOR		TTY_MAJOR
  79#define PMACZILOG_MINOR		64
  80#define PMACZILOG_NAME		"ttyS"
  81#else
  82#define PMACZILOG_MAJOR		204
  83#define PMACZILOG_MINOR		192
  84#define PMACZILOG_NAME		"ttyPZ"
  85#endif
  86
  87#define pmz_debug(fmt, arg...)	pr_debug("ttyPZ%d: " fmt, uap->port.line, ## arg)
  88#define pmz_error(fmt, arg...)	pr_err("ttyPZ%d: " fmt, uap->port.line, ## arg)
  89#define pmz_info(fmt, arg...)	pr_info("ttyPZ%d: " fmt, uap->port.line, ## arg)
  90
  91/*
  92 * For the sake of early serial console, we can do a pre-probe
  93 * (optional) of the ports at rather early boot time.
  94 */
  95static struct uart_pmac_port	pmz_ports[MAX_ZS_PORTS];
  96static int			pmz_ports_count;
  97
  98static struct uart_driver pmz_uart_reg = {
  99	.owner		=	THIS_MODULE,
 100	.driver_name	=	PMACZILOG_NAME,
 101	.dev_name	=	PMACZILOG_NAME,
 102	.major		=	PMACZILOG_MAJOR,
 103	.minor		=	PMACZILOG_MINOR,
 104};
 105
 106
 107/* 
 108 * Load all registers to reprogram the port
 109 * This function must only be called when the TX is not busy.  The UART
 110 * port lock must be held and local interrupts disabled.
 111 */
 112static void pmz_load_zsregs(struct uart_pmac_port *uap, u8 *regs)
 113{
 114	int i;
 115
 116	/* Let pending transmits finish.  */
 117	for (i = 0; i < 1000; i++) {
 118		unsigned char stat = read_zsreg(uap, R1);
 119		if (stat & ALL_SNT)
 120			break;
 121		udelay(100);
 122	}
 123
 124	ZS_CLEARERR(uap);
 125	zssync(uap);
 126	ZS_CLEARFIFO(uap);
 127	zssync(uap);
 128	ZS_CLEARERR(uap);
 129
 130	/* Disable all interrupts.  */
 131	write_zsreg(uap, R1,
 132		    regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
 133
 134	/* Set parity, sync config, stop bits, and clock divisor.  */
 135	write_zsreg(uap, R4, regs[R4]);
 136
 137	/* Set misc. TX/RX control bits.  */
 138	write_zsreg(uap, R10, regs[R10]);
 139
 140	/* Set TX/RX controls sans the enable bits.  */
 141	write_zsreg(uap, R3, regs[R3] & ~RxENABLE);
 142	write_zsreg(uap, R5, regs[R5] & ~TxENABLE);
 143
 144	/* now set R7 "prime" on ESCC */
 145	write_zsreg(uap, R15, regs[R15] | EN85C30);
 146	write_zsreg(uap, R7, regs[R7P]);
 147
 148	/* make sure we use R7 "non-prime" on ESCC */
 149	write_zsreg(uap, R15, regs[R15] & ~EN85C30);
 150
 151	/* Synchronous mode config.  */
 152	write_zsreg(uap, R6, regs[R6]);
 153	write_zsreg(uap, R7, regs[R7]);
 154
 155	/* Disable baud generator.  */
 156	write_zsreg(uap, R14, regs[R14] & ~BRENAB);
 157
 158	/* Clock mode control.  */
 159	write_zsreg(uap, R11, regs[R11]);
 160
 161	/* Lower and upper byte of baud rate generator divisor.  */
 162	write_zsreg(uap, R12, regs[R12]);
 163	write_zsreg(uap, R13, regs[R13]);
 164	
 165	/* Now rewrite R14, with BRENAB (if set).  */
 166	write_zsreg(uap, R14, regs[R14]);
 167
 168	/* Reset external status interrupts.  */
 169	write_zsreg(uap, R0, RES_EXT_INT);
 170	write_zsreg(uap, R0, RES_EXT_INT);
 171
 172	/* Rewrite R3/R5, this time without enables masked.  */
 173	write_zsreg(uap, R3, regs[R3]);
 174	write_zsreg(uap, R5, regs[R5]);
 175
 176	/* Rewrite R1, this time without IRQ enabled masked.  */
 177	write_zsreg(uap, R1, regs[R1]);
 178
 179	/* Enable interrupts */
 180	write_zsreg(uap, R9, regs[R9]);
 181}
 182
 183/* 
 184 * We do like sunzilog to avoid disrupting pending Tx
 185 * Reprogram the Zilog channel HW registers with the copies found in the
 186 * software state struct.  If the transmitter is busy, we defer this update
 187 * until the next TX complete interrupt.  Else, we do it right now.
 188 *
 189 * The UART port lock must be held and local interrupts disabled.
 190 */
 191static void pmz_maybe_update_regs(struct uart_pmac_port *uap)
 192{
 193	if (!ZS_REGS_HELD(uap)) {
 194		if (ZS_TX_ACTIVE(uap)) {
 195			uap->flags |= PMACZILOG_FLAG_REGS_HELD;
 196		} else {
 197			pmz_debug("pmz: maybe_update_regs: updating\n");
 198			pmz_load_zsregs(uap, uap->curregs);
 199		}
 200	}
 201}
 202
 203static void pmz_interrupt_control(struct uart_pmac_port *uap, int enable)
 204{
 205	if (enable) {
 206		uap->curregs[1] |= INT_ALL_Rx | TxINT_ENAB;
 207		if (!ZS_IS_EXTCLK(uap))
 208			uap->curregs[1] |= EXT_INT_ENAB;
 209	} else {
 210		uap->curregs[1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
 211	}
 212	write_zsreg(uap, R1, uap->curregs[1]);
 213}
 214
 215static bool pmz_receive_chars(struct uart_pmac_port *uap)
 216	__must_hold(&uap->port.lock)
 217{
 218	struct tty_port *port;
 219	unsigned char ch, r1, drop, flag;
 220	int loops = 0;
 221
 222	/* Sanity check, make sure the old bug is no longer happening */
 223	if (uap->port.state == NULL) {
 224		WARN_ON(1);
 225		(void)read_zsdata(uap);
 226		return false;
 227	}
 228	port = &uap->port.state->port;
 229
 230	while (1) {
 231		drop = 0;
 232
 233		r1 = read_zsreg(uap, R1);
 234		ch = read_zsdata(uap);
 235
 236		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
 237			write_zsreg(uap, R0, ERR_RES);
 238			zssync(uap);
 239		}
 240
 241		ch &= uap->parity_mask;
 242		if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {
 243			uap->flags &= ~PMACZILOG_FLAG_BREAK;
 244		}
 245
 246#if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)
 247#ifdef USE_CTRL_O_SYSRQ
 248		/* Handle the SysRq ^O Hack */
 249		if (ch == '\x0f') {
 250			uap->port.sysrq = jiffies + HZ*5;
 251			goto next_char;
 252		}
 253#endif /* USE_CTRL_O_SYSRQ */
 254		if (uap->port.sysrq) {
 255			int swallow;
 256			spin_unlock(&uap->port.lock);
 257			swallow = uart_handle_sysrq_char(&uap->port, ch);
 258			spin_lock(&uap->port.lock);
 259			if (swallow)
 260				goto next_char;
 261		}
 262#endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */
 263
 264		/* A real serial line, record the character and status.  */
 265		if (drop)
 266			goto next_char;
 267
 268		flag = TTY_NORMAL;
 269		uap->port.icount.rx++;
 270
 271		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
 272			if (r1 & BRK_ABRT) {
 273				pmz_debug("pmz: got break !\n");
 274				r1 &= ~(PAR_ERR | CRC_ERR);
 275				uap->port.icount.brk++;
 276				if (uart_handle_break(&uap->port))
 277					goto next_char;
 278			}
 279			else if (r1 & PAR_ERR)
 280				uap->port.icount.parity++;
 281			else if (r1 & CRC_ERR)
 282				uap->port.icount.frame++;
 283			if (r1 & Rx_OVR)
 284				uap->port.icount.overrun++;
 285			r1 &= uap->port.read_status_mask;
 286			if (r1 & BRK_ABRT)
 287				flag = TTY_BREAK;
 288			else if (r1 & PAR_ERR)
 289				flag = TTY_PARITY;
 290			else if (r1 & CRC_ERR)
 291				flag = TTY_FRAME;
 292		}
 293
 294		if (uap->port.ignore_status_mask == 0xff ||
 295		    (r1 & uap->port.ignore_status_mask) == 0) {
 296			tty_insert_flip_char(port, ch, flag);
 297		}
 298		if (r1 & Rx_OVR)
 299			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 300	next_char:
 301		/* We can get stuck in an infinite loop getting char 0 when the
 302		 * line is in a wrong HW state, we break that here.
 303		 * When that happens, I disable the receive side of the driver.
 304		 * Note that what I've been experiencing is a real irq loop where
 305		 * I'm getting flooded regardless of the actual port speed.
 306		 * Something strange is going on with the HW
 307		 */
 308		if ((++loops) > 1000)
 309			goto flood;
 310		ch = read_zsreg(uap, R0);
 311		if (!(ch & Rx_CH_AV))
 312			break;
 313	}
 314
 315	return true;
 316 flood:
 317	pmz_interrupt_control(uap, 0);
 318	pmz_error("pmz: rx irq flood !\n");
 319	return true;
 320}
 321
 322static void pmz_status_handle(struct uart_pmac_port *uap)
 323{
 324	unsigned char status;
 325
 326	status = read_zsreg(uap, R0);
 327	write_zsreg(uap, R0, RES_EXT_INT);
 328	zssync(uap);
 329
 330	if (ZS_IS_OPEN(uap) && ZS_WANTS_MODEM_STATUS(uap)) {
 331		if (status & SYNC_HUNT)
 332			uap->port.icount.dsr++;
 333
 334		/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
 335		 * But it does not tell us which bit has changed, we have to keep
 336		 * track of this ourselves.
 337		 * The CTS input is inverted for some reason.  -- paulus
 338		 */
 339		if ((status ^ uap->prev_status) & DCD)
 340			uart_handle_dcd_change(&uap->port,
 341					       (status & DCD));
 342		if ((status ^ uap->prev_status) & CTS)
 343			uart_handle_cts_change(&uap->port,
 344					       !(status & CTS));
 345
 346		wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
 347	}
 348
 349	if (status & BRK_ABRT)
 350		uap->flags |= PMACZILOG_FLAG_BREAK;
 351
 352	uap->prev_status = status;
 353}
 354
 355static void pmz_transmit_chars(struct uart_pmac_port *uap)
 356{
 357	struct circ_buf *xmit;
 358
 359	if (ZS_IS_CONS(uap)) {
 360		unsigned char status = read_zsreg(uap, R0);
 361
 362		/* TX still busy?  Just wait for the next TX done interrupt.
 363		 *
 364		 * It can occur because of how we do serial console writes.  It would
 365		 * be nice to transmit console writes just like we normally would for
 366		 * a TTY line. (ie. buffered and TX interrupt driven).  That is not
 367		 * easy because console writes cannot sleep.  One solution might be
 368		 * to poll on enough port->xmit space becoming free.  -DaveM
 369		 */
 370		if (!(status & Tx_BUF_EMP))
 371			return;
 372	}
 373
 374	uap->flags &= ~PMACZILOG_FLAG_TX_ACTIVE;
 375
 376	if (ZS_REGS_HELD(uap)) {
 377		pmz_load_zsregs(uap, uap->curregs);
 378		uap->flags &= ~PMACZILOG_FLAG_REGS_HELD;
 379	}
 380
 381	if (ZS_TX_STOPPED(uap)) {
 382		uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
 383		goto ack_tx_int;
 384	}
 385
 386	/* Under some circumstances, we see interrupts reported for
 387	 * a closed channel. The interrupt mask in R1 is clear, but
 388	 * R3 still signals the interrupts and we see them when taking
 389	 * an interrupt for the other channel (this could be a qemu
 390	 * bug but since the ESCC doc doesn't specify precsiely whether
 391	 * R3 interrup status bits are masked by R1 interrupt enable
 392	 * bits, better safe than sorry). --BenH.
 393	 */
 394	if (!ZS_IS_OPEN(uap))
 395		goto ack_tx_int;
 396
 397	if (uap->port.x_char) {
 398		uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
 399		write_zsdata(uap, uap->port.x_char);
 400		zssync(uap);
 401		uap->port.icount.tx++;
 402		uap->port.x_char = 0;
 403		return;
 404	}
 405
 406	if (uap->port.state == NULL)
 407		goto ack_tx_int;
 408	xmit = &uap->port.state->xmit;
 409	if (uart_circ_empty(xmit)) {
 410		uart_write_wakeup(&uap->port);
 411		goto ack_tx_int;
 412	}
 413	if (uart_tx_stopped(&uap->port))
 414		goto ack_tx_int;
 415
 416	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
 417	write_zsdata(uap, xmit->buf[xmit->tail]);
 418	zssync(uap);
 419
 420	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 421	uap->port.icount.tx++;
 422
 423	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 424		uart_write_wakeup(&uap->port);
 425
 426	return;
 427
 428ack_tx_int:
 429	write_zsreg(uap, R0, RES_Tx_P);
 430	zssync(uap);
 431}
 432
 433/* Hrm... we register that twice, fixme later.... */
 434static irqreturn_t pmz_interrupt(int irq, void *dev_id)
 435{
 436	struct uart_pmac_port *uap = dev_id;
 437	struct uart_pmac_port *uap_a;
 438	struct uart_pmac_port *uap_b;
 439	int rc = IRQ_NONE;
 440	bool push;
 441	u8 r3;
 442
 443	uap_a = pmz_get_port_A(uap);
 444	uap_b = uap_a->mate;
 445
 446	spin_lock(&uap_a->port.lock);
 447	r3 = read_zsreg(uap_a, R3);
 448
 449#ifdef DEBUG_HARD
 450	pmz_debug("irq, r3: %x\n", r3);
 451#endif
 452	/* Channel A */
 453	push = false;
 454	if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
 455		if (!ZS_IS_OPEN(uap_a)) {
 456			pmz_debug("ChanA interrupt while not open !\n");
 457			goto skip_a;
 458		}
 459		write_zsreg(uap_a, R0, RES_H_IUS);
 460		zssync(uap_a);		
 461		if (r3 & CHAEXT)
 462			pmz_status_handle(uap_a);
 463		if (r3 & CHARxIP)
 464			push = pmz_receive_chars(uap_a);
 465		if (r3 & CHATxIP)
 466			pmz_transmit_chars(uap_a);
 467		rc = IRQ_HANDLED;
 468	}
 469 skip_a:
 470	spin_unlock(&uap_a->port.lock);
 471	if (push)
 472		tty_flip_buffer_push(&uap->port.state->port);
 473
 474	if (!uap_b)
 475		goto out;
 476
 477	spin_lock(&uap_b->port.lock);
 478	push = false;
 479	if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
 480		if (!ZS_IS_OPEN(uap_b)) {
 481			pmz_debug("ChanB interrupt while not open !\n");
 482			goto skip_b;
 483		}
 484		write_zsreg(uap_b, R0, RES_H_IUS);
 485		zssync(uap_b);
 486		if (r3 & CHBEXT)
 487			pmz_status_handle(uap_b);
 488		if (r3 & CHBRxIP)
 489			push = pmz_receive_chars(uap_b);
 490		if (r3 & CHBTxIP)
 491			pmz_transmit_chars(uap_b);
 492		rc = IRQ_HANDLED;
 493	}
 494 skip_b:
 495	spin_unlock(&uap_b->port.lock);
 496	if (push)
 497		tty_flip_buffer_push(&uap->port.state->port);
 498
 499 out:
 500	return rc;
 501}
 502
 503/*
 504 * Peek the status register, lock not held by caller
 505 */
 506static inline u8 pmz_peek_status(struct uart_pmac_port *uap)
 507{
 508	unsigned long flags;
 509	u8 status;
 510	
 511	spin_lock_irqsave(&uap->port.lock, flags);
 512	status = read_zsreg(uap, R0);
 513	spin_unlock_irqrestore(&uap->port.lock, flags);
 514
 515	return status;
 516}
 517
 518/* 
 519 * Check if transmitter is empty
 520 * The port lock is not held.
 521 */
 522static unsigned int pmz_tx_empty(struct uart_port *port)
 523{
 524	unsigned char status;
 525
 526	status = pmz_peek_status(to_pmz(port));
 527	if (status & Tx_BUF_EMP)
 528		return TIOCSER_TEMT;
 529	return 0;
 530}
 531
 532/* 
 533 * Set Modem Control (RTS & DTR) bits
 534 * The port lock is held and interrupts are disabled.
 535 * Note: Shall we really filter out RTS on external ports or
 536 * should that be dealt at higher level only ?
 537 */
 538static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
 539{
 540	struct uart_pmac_port *uap = to_pmz(port);
 541	unsigned char set_bits, clear_bits;
 542
 543        /* Do nothing for irda for now... */
 544	if (ZS_IS_IRDA(uap))
 545		return;
 546	/* We get called during boot with a port not up yet */
 547	if (!(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))
 548		return;
 549
 550	set_bits = clear_bits = 0;
 551
 552	if (ZS_IS_INTMODEM(uap)) {
 553		if (mctrl & TIOCM_RTS)
 554			set_bits |= RTS;
 555		else
 556			clear_bits |= RTS;
 557	}
 558	if (mctrl & TIOCM_DTR)
 559		set_bits |= DTR;
 560	else
 561		clear_bits |= DTR;
 562
 563	/* NOTE: Not subject to 'transmitter active' rule.  */ 
 564	uap->curregs[R5] |= set_bits;
 565	uap->curregs[R5] &= ~clear_bits;
 566
 567	write_zsreg(uap, R5, uap->curregs[R5]);
 568	pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",
 569		  set_bits, clear_bits, uap->curregs[R5]);
 570	zssync(uap);
 571}
 572
 573/* 
 574 * Get Modem Control bits (only the input ones, the core will
 575 * or that with a cached value of the control ones)
 576 * The port lock is held and interrupts are disabled.
 577 */
 578static unsigned int pmz_get_mctrl(struct uart_port *port)
 579{
 580	struct uart_pmac_port *uap = to_pmz(port);
 581	unsigned char status;
 582	unsigned int ret;
 583
 584	status = read_zsreg(uap, R0);
 585
 586	ret = 0;
 587	if (status & DCD)
 588		ret |= TIOCM_CAR;
 589	if (status & SYNC_HUNT)
 590		ret |= TIOCM_DSR;
 591	if (!(status & CTS))
 592		ret |= TIOCM_CTS;
 593
 594	return ret;
 595}
 596
 597/* 
 598 * Stop TX side. Dealt like sunzilog at next Tx interrupt,
 599 * though for DMA, we will have to do a bit more.
 600 * The port lock is held and interrupts are disabled.
 601 */
 602static void pmz_stop_tx(struct uart_port *port)
 603{
 604	to_pmz(port)->flags |= PMACZILOG_FLAG_TX_STOPPED;
 605}
 606
 607/* 
 608 * Kick the Tx side.
 609 * The port lock is held and interrupts are disabled.
 610 */
 611static void pmz_start_tx(struct uart_port *port)
 612{
 613	struct uart_pmac_port *uap = to_pmz(port);
 614	unsigned char status;
 615
 616	pmz_debug("pmz: start_tx()\n");
 617
 618	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
 619	uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
 620
 621	status = read_zsreg(uap, R0);
 622
 623	/* TX busy?  Just wait for the TX done interrupt.  */
 624	if (!(status & Tx_BUF_EMP))
 625		return;
 626
 627	/* Send the first character to jump-start the TX done
 628	 * IRQ sending engine.
 629	 */
 630	if (port->x_char) {
 631		write_zsdata(uap, port->x_char);
 632		zssync(uap);
 633		port->icount.tx++;
 634		port->x_char = 0;
 635	} else {
 636		struct circ_buf *xmit = &port->state->xmit;
 637
 638		if (uart_circ_empty(xmit))
 639			goto out;
 640		write_zsdata(uap, xmit->buf[xmit->tail]);
 641		zssync(uap);
 642		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 643		port->icount.tx++;
 644
 645		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 646			uart_write_wakeup(&uap->port);
 647	}
 648 out:
 649	pmz_debug("pmz: start_tx() done.\n");
 650}
 651
 652/* 
 653 * Stop Rx side, basically disable emitting of
 654 * Rx interrupts on the port. We don't disable the rx
 655 * side of the chip proper though
 656 * The port lock is held.
 657 */
 658static void pmz_stop_rx(struct uart_port *port)
 659{
 660	struct uart_pmac_port *uap = to_pmz(port);
 661
 662	pmz_debug("pmz: stop_rx()()\n");
 663
 664	/* Disable all RX interrupts.  */
 665	uap->curregs[R1] &= ~RxINT_MASK;
 666	pmz_maybe_update_regs(uap);
 667
 668	pmz_debug("pmz: stop_rx() done.\n");
 669}
 670
 671/* 
 672 * Enable modem status change interrupts
 673 * The port lock is held.
 674 */
 675static void pmz_enable_ms(struct uart_port *port)
 676{
 677	struct uart_pmac_port *uap = to_pmz(port);
 678	unsigned char new_reg;
 679
 680	if (ZS_IS_IRDA(uap))
 681		return;
 682	new_reg = uap->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
 683	if (new_reg != uap->curregs[R15]) {
 684		uap->curregs[R15] = new_reg;
 685
 686		/* NOTE: Not subject to 'transmitter active' rule. */
 687		write_zsreg(uap, R15, uap->curregs[R15]);
 688	}
 689}
 690
 691/* 
 692 * Control break state emission
 693 * The port lock is not held.
 694 */
 695static void pmz_break_ctl(struct uart_port *port, int break_state)
 696{
 697	struct uart_pmac_port *uap = to_pmz(port);
 698	unsigned char set_bits, clear_bits, new_reg;
 699	unsigned long flags;
 700
 701	set_bits = clear_bits = 0;
 702
 703	if (break_state)
 704		set_bits |= SND_BRK;
 705	else
 706		clear_bits |= SND_BRK;
 707
 708	spin_lock_irqsave(&port->lock, flags);
 709
 710	new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits;
 711	if (new_reg != uap->curregs[R5]) {
 712		uap->curregs[R5] = new_reg;
 713		write_zsreg(uap, R5, uap->curregs[R5]);
 714	}
 715
 716	spin_unlock_irqrestore(&port->lock, flags);
 717}
 718
 719#ifdef CONFIG_PPC_PMAC
 720
 721/*
 722 * Turn power on or off to the SCC and associated stuff
 723 * (port drivers, modem, IR port, etc.)
 724 * Returns the number of milliseconds we should wait before
 725 * trying to use the port.
 726 */
 727static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
 728{
 729	int delay = 0;
 730	int rc;
 731
 732	if (state) {
 733		rc = pmac_call_feature(
 734			PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);
 735		pmz_debug("port power on result: %d\n", rc);
 736		if (ZS_IS_INTMODEM(uap)) {
 737			rc = pmac_call_feature(
 738				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);
 739			delay = 2500;	/* wait for 2.5s before using */
 740			pmz_debug("modem power result: %d\n", rc);
 741		}
 742	} else {
 743		/* TODO: Make that depend on a timer, don't power down
 744		 * immediately
 745		 */
 746		if (ZS_IS_INTMODEM(uap)) {
 747			rc = pmac_call_feature(
 748				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);
 749			pmz_debug("port power off result: %d\n", rc);
 750		}
 751		pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);
 752	}
 753	return delay;
 754}
 755
 756#else
 757
 758static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
 759{
 760	return 0;
 761}
 762
 763#endif /* !CONFIG_PPC_PMAC */
 764
 765/*
 766 * FixZeroBug....Works around a bug in the SCC receiving channel.
 767 * Inspired from Darwin code, 15 Sept. 2000  -DanM
 768 *
 769 * The following sequence prevents a problem that is seen with O'Hare ASICs
 770 * (most versions -- also with some Heathrow and Hydra ASICs) where a zero
 771 * at the input to the receiver becomes 'stuck' and locks up the receiver.
 772 * This problem can occur as a result of a zero bit at the receiver input
 773 * coincident with any of the following events:
 774 *
 775 *	The SCC is initialized (hardware or software).
 776 *	A framing error is detected.
 777 *	The clocking option changes from synchronous or X1 asynchronous
 778 *		clocking to X16, X32, or X64 asynchronous clocking.
 779 *	The decoding mode is changed among NRZ, NRZI, FM0, or FM1.
 780 *
 781 * This workaround attempts to recover from the lockup condition by placing
 782 * the SCC in synchronous loopback mode with a fast clock before programming
 783 * any of the asynchronous modes.
 784 */
 785static void pmz_fix_zero_bug_scc(struct uart_pmac_port *uap)
 786{
 787	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
 788	zssync(uap);
 789	udelay(10);
 790	write_zsreg(uap, 9, (ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB) | NV);
 791	zssync(uap);
 792
 793	write_zsreg(uap, 4, X1CLK | MONSYNC);
 794	write_zsreg(uap, 3, Rx8);
 795	write_zsreg(uap, 5, Tx8 | RTS);
 796	write_zsreg(uap, 9, NV);	/* Didn't we already do this? */
 797	write_zsreg(uap, 11, RCBR | TCBR);
 798	write_zsreg(uap, 12, 0);
 799	write_zsreg(uap, 13, 0);
 800	write_zsreg(uap, 14, (LOOPBAK | BRSRC));
 801	write_zsreg(uap, 14, (LOOPBAK | BRSRC | BRENAB));
 802	write_zsreg(uap, 3, Rx8 | RxENABLE);
 803	write_zsreg(uap, 0, RES_EXT_INT);
 804	write_zsreg(uap, 0, RES_EXT_INT);
 805	write_zsreg(uap, 0, RES_EXT_INT);	/* to kill some time */
 806
 807	/* The channel should be OK now, but it is probably receiving
 808	 * loopback garbage.
 809	 * Switch to asynchronous mode, disable the receiver,
 810	 * and discard everything in the receive buffer.
 811	 */
 812	write_zsreg(uap, 9, NV);
 813	write_zsreg(uap, 4, X16CLK | SB_MASK);
 814	write_zsreg(uap, 3, Rx8);
 815
 816	while (read_zsreg(uap, 0) & Rx_CH_AV) {
 817		(void)read_zsreg(uap, 8);
 818		write_zsreg(uap, 0, RES_EXT_INT);
 819		write_zsreg(uap, 0, ERR_RES);
 820	}
 821}
 822
 823/*
 824 * Real startup routine, powers up the hardware and sets up
 825 * the SCC. Returns a delay in ms where you need to wait before
 826 * actually using the port, this is typically the internal modem
 827 * powerup delay. This routine expect the lock to be taken.
 828 */
 829static int __pmz_startup(struct uart_pmac_port *uap)
 830{
 831	int pwr_delay = 0;
 832
 833	memset(&uap->curregs, 0, sizeof(uap->curregs));
 834
 835	/* Power up the SCC & underlying hardware (modem/irda) */
 836	pwr_delay = pmz_set_scc_power(uap, 1);
 837
 838	/* Nice buggy HW ... */
 839	pmz_fix_zero_bug_scc(uap);
 840
 841	/* Reset the channel */
 842	uap->curregs[R9] = 0;
 843	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
 844	zssync(uap);
 845	udelay(10);
 846	write_zsreg(uap, 9, 0);
 847	zssync(uap);
 848
 849	/* Clear the interrupt registers */
 850	write_zsreg(uap, R1, 0);
 851	write_zsreg(uap, R0, ERR_RES);
 852	write_zsreg(uap, R0, ERR_RES);
 853	write_zsreg(uap, R0, RES_H_IUS);
 854	write_zsreg(uap, R0, RES_H_IUS);
 855
 856	/* Setup some valid baud rate */
 857	uap->curregs[R4] = X16CLK | SB1;
 858	uap->curregs[R3] = Rx8;
 859	uap->curregs[R5] = Tx8 | RTS;
 860	if (!ZS_IS_IRDA(uap))
 861		uap->curregs[R5] |= DTR;
 862	uap->curregs[R12] = 0;
 863	uap->curregs[R13] = 0;
 864	uap->curregs[R14] = BRENAB;
 865
 866	/* Clear handshaking, enable BREAK interrupts */
 867	uap->curregs[R15] = BRKIE;
 868
 869	/* Master interrupt enable */
 870	uap->curregs[R9] |= NV | MIE;
 871
 872	pmz_load_zsregs(uap, uap->curregs);
 873
 874	/* Enable receiver and transmitter.  */
 875	write_zsreg(uap, R3, uap->curregs[R3] |= RxENABLE);
 876	write_zsreg(uap, R5, uap->curregs[R5] |= TxENABLE);
 877
 878	/* Remember status for DCD/CTS changes */
 879	uap->prev_status = read_zsreg(uap, R0);
 880
 881	return pwr_delay;
 882}
 883
 884static void pmz_irda_reset(struct uart_pmac_port *uap)
 885{
 886	unsigned long flags;
 887
 888	spin_lock_irqsave(&uap->port.lock, flags);
 889	uap->curregs[R5] |= DTR;
 890	write_zsreg(uap, R5, uap->curregs[R5]);
 891	zssync(uap);
 892	spin_unlock_irqrestore(&uap->port.lock, flags);
 893	msleep(110);
 894
 895	spin_lock_irqsave(&uap->port.lock, flags);
 896	uap->curregs[R5] &= ~DTR;
 897	write_zsreg(uap, R5, uap->curregs[R5]);
 898	zssync(uap);
 899	spin_unlock_irqrestore(&uap->port.lock, flags);
 900	msleep(10);
 901}
 902
 903/*
 904 * This is the "normal" startup routine, using the above one
 905 * wrapped with the lock and doing a schedule delay
 906 */
 907static int pmz_startup(struct uart_port *port)
 908{
 909	struct uart_pmac_port *uap = to_pmz(port);
 910	unsigned long flags;
 911	int pwr_delay = 0;
 912
 913	pmz_debug("pmz: startup()\n");
 914
 915	uap->flags |= PMACZILOG_FLAG_IS_OPEN;
 916
 917	/* A console is never powered down. Else, power up and
 918	 * initialize the chip
 919	 */
 920	if (!ZS_IS_CONS(uap)) {
 921		spin_lock_irqsave(&port->lock, flags);
 922		pwr_delay = __pmz_startup(uap);
 923		spin_unlock_irqrestore(&port->lock, flags);
 924	}	
 925	sprintf(uap->irq_name, PMACZILOG_NAME"%d", uap->port.line);
 926	if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED,
 927			uap->irq_name, uap)) {
 928		pmz_error("Unable to register zs interrupt handler.\n");
 929		pmz_set_scc_power(uap, 0);
 930		return -ENXIO;
 931	}
 932
 933	/* Right now, we deal with delay by blocking here, I'll be
 934	 * smarter later on
 935	 */
 936	if (pwr_delay != 0) {
 937		pmz_debug("pmz: delaying %d ms\n", pwr_delay);
 938		msleep(pwr_delay);
 939	}
 940
 941	/* IrDA reset is done now */
 942	if (ZS_IS_IRDA(uap))
 943		pmz_irda_reset(uap);
 944
 945	/* Enable interrupt requests for the channel */
 946	spin_lock_irqsave(&port->lock, flags);
 947	pmz_interrupt_control(uap, 1);
 948	spin_unlock_irqrestore(&port->lock, flags);
 949
 950	pmz_debug("pmz: startup() done.\n");
 951
 952	return 0;
 953}
 954
 955static void pmz_shutdown(struct uart_port *port)
 956{
 957	struct uart_pmac_port *uap = to_pmz(port);
 958	unsigned long flags;
 959
 960	pmz_debug("pmz: shutdown()\n");
 961
 962	spin_lock_irqsave(&port->lock, flags);
 963
 964	/* Disable interrupt requests for the channel */
 965	pmz_interrupt_control(uap, 0);
 966
 967	if (!ZS_IS_CONS(uap)) {
 968		/* Disable receiver and transmitter */
 969		uap->curregs[R3] &= ~RxENABLE;
 970		uap->curregs[R5] &= ~TxENABLE;
 971
 972		/* Disable break assertion */
 973		uap->curregs[R5] &= ~SND_BRK;
 974		pmz_maybe_update_regs(uap);
 975	}
 976
 977	spin_unlock_irqrestore(&port->lock, flags);
 978
 979	/* Release interrupt handler */
 980	free_irq(uap->port.irq, uap);
 981
 982	spin_lock_irqsave(&port->lock, flags);
 983
 984	uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;
 985
 986	if (!ZS_IS_CONS(uap))
 987		pmz_set_scc_power(uap, 0);	/* Shut the chip down */
 988
 989	spin_unlock_irqrestore(&port->lock, flags);
 990
 991	pmz_debug("pmz: shutdown() done.\n");
 992}
 993
 994/* Shared by TTY driver and serial console setup.  The port lock is held
 995 * and local interrupts are disabled.
 996 */
 997static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
 998			      unsigned int iflag, unsigned long baud)
 999{
1000	int brg;
1001
1002	/* Switch to external clocking for IrDA high clock rates. That
1003	 * code could be re-used for Midi interfaces with different
1004	 * multipliers
1005	 */
1006	if (baud >= 115200 && ZS_IS_IRDA(uap)) {
1007		uap->curregs[R4] = X1CLK;
1008		uap->curregs[R11] = RCTRxCP | TCTRxCP;
1009		uap->curregs[R14] = 0; /* BRG off */
1010		uap->curregs[R12] = 0;
1011		uap->curregs[R13] = 0;
1012		uap->flags |= PMACZILOG_FLAG_IS_EXTCLK;
1013	} else {
1014		switch (baud) {
1015		case ZS_CLOCK/16:	/* 230400 */
1016			uap->curregs[R4] = X16CLK;
1017			uap->curregs[R11] = 0;
1018			uap->curregs[R14] = 0;
1019			break;
1020		case ZS_CLOCK/32:	/* 115200 */
1021			uap->curregs[R4] = X32CLK;
1022			uap->curregs[R11] = 0;
1023			uap->curregs[R14] = 0;
1024			break;
1025		default:
1026			uap->curregs[R4] = X16CLK;
1027			uap->curregs[R11] = TCBR | RCBR;
1028			brg = BPS_TO_BRG(baud, ZS_CLOCK / 16);
1029			uap->curregs[R12] = (brg & 255);
1030			uap->curregs[R13] = ((brg >> 8) & 255);
1031			uap->curregs[R14] = BRENAB;
1032		}
1033		uap->flags &= ~PMACZILOG_FLAG_IS_EXTCLK;
1034	}
1035
1036	/* Character size, stop bits, and parity. */
1037	uap->curregs[3] &= ~RxN_MASK;
1038	uap->curregs[5] &= ~TxN_MASK;
1039
1040	switch (cflag & CSIZE) {
1041	case CS5:
1042		uap->curregs[3] |= Rx5;
1043		uap->curregs[5] |= Tx5;
1044		uap->parity_mask = 0x1f;
1045		break;
1046	case CS6:
1047		uap->curregs[3] |= Rx6;
1048		uap->curregs[5] |= Tx6;
1049		uap->parity_mask = 0x3f;
1050		break;
1051	case CS7:
1052		uap->curregs[3] |= Rx7;
1053		uap->curregs[5] |= Tx7;
1054		uap->parity_mask = 0x7f;
1055		break;
1056	case CS8:
1057	default:
1058		uap->curregs[3] |= Rx8;
1059		uap->curregs[5] |= Tx8;
1060		uap->parity_mask = 0xff;
1061		break;
1062	}
1063	uap->curregs[4] &= ~(SB_MASK);
1064	if (cflag & CSTOPB)
1065		uap->curregs[4] |= SB2;
1066	else
1067		uap->curregs[4] |= SB1;
1068	if (cflag & PARENB)
1069		uap->curregs[4] |= PAR_ENAB;
1070	else
1071		uap->curregs[4] &= ~PAR_ENAB;
1072	if (!(cflag & PARODD))
1073		uap->curregs[4] |= PAR_EVEN;
1074	else
1075		uap->curregs[4] &= ~PAR_EVEN;
1076
1077	uap->port.read_status_mask = Rx_OVR;
1078	if (iflag & INPCK)
1079		uap->port.read_status_mask |= CRC_ERR | PAR_ERR;
1080	if (iflag & (IGNBRK | BRKINT | PARMRK))
1081		uap->port.read_status_mask |= BRK_ABRT;
1082
1083	uap->port.ignore_status_mask = 0;
1084	if (iflag & IGNPAR)
1085		uap->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
1086	if (iflag & IGNBRK) {
1087		uap->port.ignore_status_mask |= BRK_ABRT;
1088		if (iflag & IGNPAR)
1089			uap->port.ignore_status_mask |= Rx_OVR;
1090	}
1091
1092	if ((cflag & CREAD) == 0)
1093		uap->port.ignore_status_mask = 0xff;
1094}
1095
1096
1097/*
1098 * Set the irda codec on the imac to the specified baud rate.
1099 */
1100static void pmz_irda_setup(struct uart_pmac_port *uap, unsigned long *baud)
1101{
1102	u8 cmdbyte;
1103	int t, version;
1104
1105	switch (*baud) {
1106	/* SIR modes */
1107	case 2400:
1108		cmdbyte = 0x53;
1109		break;
1110	case 4800:
1111		cmdbyte = 0x52;
1112		break;
1113	case 9600:
1114		cmdbyte = 0x51;
1115		break;
1116	case 19200:
1117		cmdbyte = 0x50;
1118		break;
1119	case 38400:
1120		cmdbyte = 0x4f;
1121		break;
1122	case 57600:
1123		cmdbyte = 0x4e;
1124		break;
1125	case 115200:
1126		cmdbyte = 0x4d;
1127		break;
1128	/* The FIR modes aren't really supported at this point, how
1129	 * do we select the speed ? via the FCR on KeyLargo ?
1130	 */
1131	case 1152000:
1132		cmdbyte = 0;
1133		break;
1134	case 4000000:
1135		cmdbyte = 0;
1136		break;
1137	default: /* 9600 */
1138		cmdbyte = 0x51;
1139		*baud = 9600;
1140		break;
1141	}
1142
1143	/* Wait for transmitter to drain */
1144	t = 10000;
1145	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0
1146	       || (read_zsreg(uap, R1) & ALL_SNT) == 0) {
1147		if (--t <= 0) {
1148			pmz_error("transmitter didn't drain\n");
1149			return;
1150		}
1151		udelay(10);
1152	}
1153
1154	/* Drain the receiver too */
1155	t = 100;
1156	(void)read_zsdata(uap);
1157	(void)read_zsdata(uap);
1158	(void)read_zsdata(uap);
1159	mdelay(10);
1160	while (read_zsreg(uap, R0) & Rx_CH_AV) {
1161		read_zsdata(uap);
1162		mdelay(10);
1163		if (--t <= 0) {
1164			pmz_error("receiver didn't drain\n");
1165			return;
1166		}
1167	}
1168
1169	/* Switch to command mode */
1170	uap->curregs[R5] |= DTR;
1171	write_zsreg(uap, R5, uap->curregs[R5]);
1172	zssync(uap);
1173	mdelay(1);
1174
1175	/* Switch SCC to 19200 */
1176	pmz_convert_to_zs(uap, CS8, 0, 19200);		
1177	pmz_load_zsregs(uap, uap->curregs);
1178	mdelay(1);
1179
1180	/* Write get_version command byte */
1181	write_zsdata(uap, 1);
1182	t = 5000;
1183	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1184		if (--t <= 0) {
1185			pmz_error("irda_setup timed out on get_version byte\n");
1186			goto out;
1187		}
1188		udelay(10);
1189	}
1190	version = read_zsdata(uap);
1191
1192	if (version < 4) {
1193		pmz_info("IrDA: dongle version %d not supported\n", version);
1194		goto out;
1195	}
1196
1197	/* Send speed mode */
1198	write_zsdata(uap, cmdbyte);
1199	t = 5000;
1200	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1201		if (--t <= 0) {
1202			pmz_error("irda_setup timed out on speed mode byte\n");
1203			goto out;
1204		}
1205		udelay(10);
1206	}
1207	t = read_zsdata(uap);
1208	if (t != cmdbyte)
1209		pmz_error("irda_setup speed mode byte = %x (%x)\n", t, cmdbyte);
1210
1211	pmz_info("IrDA setup for %ld bps, dongle version: %d\n",
1212		 *baud, version);
1213
1214	(void)read_zsdata(uap);
1215	(void)read_zsdata(uap);
1216	(void)read_zsdata(uap);
1217
1218 out:
1219	/* Switch back to data mode */
1220	uap->curregs[R5] &= ~DTR;
1221	write_zsreg(uap, R5, uap->curregs[R5]);
1222	zssync(uap);
1223
1224	(void)read_zsdata(uap);
1225	(void)read_zsdata(uap);
1226	(void)read_zsdata(uap);
1227}
1228
1229
1230static void __pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1231			      struct ktermios *old)
1232{
1233	struct uart_pmac_port *uap = to_pmz(port);
1234	unsigned long baud;
1235
1236	pmz_debug("pmz: set_termios()\n");
1237
1238	memcpy(&uap->termios_cache, termios, sizeof(struct ktermios));
1239
1240	/* XXX Check which revs of machines actually allow 1 and 4Mb speeds
1241	 * on the IR dongle. Note that the IRTTY driver currently doesn't know
1242	 * about the FIR mode and high speed modes. So these are unused. For
1243	 * implementing proper support for these, we should probably add some
1244	 * DMA as well, at least on the Rx side, which isn't a simple thing
1245	 * at this point.
1246	 */
1247	if (ZS_IS_IRDA(uap)) {
1248		/* Calc baud rate */
1249		baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);
1250		pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);
1251		/* Cet the irda codec to the right rate */
1252		pmz_irda_setup(uap, &baud);
1253		/* Set final baud rate */
1254		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1255		pmz_load_zsregs(uap, uap->curregs);
1256		zssync(uap);
1257	} else {
1258		baud = uart_get_baud_rate(port, termios, old, 1200, 230400);
1259		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1260		/* Make sure modem status interrupts are correctly configured */
1261		if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {
1262			uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;
1263			uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;
1264		} else {
1265			uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);
1266			uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;
1267		}
1268
1269		/* Load registers to the chip */
1270		pmz_maybe_update_regs(uap);
1271	}
1272	uart_update_timeout(port, termios->c_cflag, baud);
1273
1274	pmz_debug("pmz: set_termios() done.\n");
1275}
1276
1277/* The port lock is not held.  */
1278static void pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1279			    struct ktermios *old)
1280{
1281	struct uart_pmac_port *uap = to_pmz(port);
1282	unsigned long flags;
1283
1284	spin_lock_irqsave(&port->lock, flags);	
1285
1286	/* Disable IRQs on the port */
1287	pmz_interrupt_control(uap, 0);
1288
1289	/* Setup new port configuration */
1290	__pmz_set_termios(port, termios, old);
1291
1292	/* Re-enable IRQs on the port */
1293	if (ZS_IS_OPEN(uap))
1294		pmz_interrupt_control(uap, 1);
1295
1296	spin_unlock_irqrestore(&port->lock, flags);
1297}
1298
1299static const char *pmz_type(struct uart_port *port)
1300{
1301	struct uart_pmac_port *uap = to_pmz(port);
1302
1303	if (ZS_IS_IRDA(uap))
1304		return "Z85c30 ESCC - Infrared port";
1305	else if (ZS_IS_INTMODEM(uap))
1306		return "Z85c30 ESCC - Internal modem";
1307	return "Z85c30 ESCC - Serial port";
1308}
1309
1310/* We do not request/release mappings of the registers here, this
1311 * happens at early serial probe time.
1312 */
1313static void pmz_release_port(struct uart_port *port)
1314{
1315}
1316
1317static int pmz_request_port(struct uart_port *port)
1318{
1319	return 0;
1320}
1321
1322/* These do not need to do anything interesting either.  */
1323static void pmz_config_port(struct uart_port *port, int flags)
1324{
1325}
1326
1327/* We do not support letting the user mess with the divisor, IRQ, etc. */
1328static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)
1329{
1330	return -EINVAL;
1331}
1332
1333#ifdef CONFIG_CONSOLE_POLL
1334
1335static int pmz_poll_get_char(struct uart_port *port)
1336{
1337	struct uart_pmac_port *uap =
1338		container_of(port, struct uart_pmac_port, port);
1339	int tries = 2;
1340
1341	while (tries) {
1342		if ((read_zsreg(uap, R0) & Rx_CH_AV) != 0)
1343			return read_zsdata(uap);
1344		if (tries--)
1345			udelay(5);
1346	}
1347
1348	return NO_POLL_CHAR;
1349}
1350
1351static void pmz_poll_put_char(struct uart_port *port, unsigned char c)
1352{
1353	struct uart_pmac_port *uap =
1354		container_of(port, struct uart_pmac_port, port);
1355
1356	/* Wait for the transmit buffer to empty. */
1357	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1358		udelay(5);
1359	write_zsdata(uap, c);
1360}
1361
1362#endif /* CONFIG_CONSOLE_POLL */
1363
1364static const struct uart_ops pmz_pops = {
1365	.tx_empty	=	pmz_tx_empty,
1366	.set_mctrl	=	pmz_set_mctrl,
1367	.get_mctrl	=	pmz_get_mctrl,
1368	.stop_tx	=	pmz_stop_tx,
1369	.start_tx	=	pmz_start_tx,
1370	.stop_rx	=	pmz_stop_rx,
1371	.enable_ms	=	pmz_enable_ms,
1372	.break_ctl	=	pmz_break_ctl,
1373	.startup	=	pmz_startup,
1374	.shutdown	=	pmz_shutdown,
1375	.set_termios	=	pmz_set_termios,
1376	.type		=	pmz_type,
1377	.release_port	=	pmz_release_port,
1378	.request_port	=	pmz_request_port,
1379	.config_port	=	pmz_config_port,
1380	.verify_port	=	pmz_verify_port,
1381#ifdef CONFIG_CONSOLE_POLL
1382	.poll_get_char	=	pmz_poll_get_char,
1383	.poll_put_char	=	pmz_poll_put_char,
1384#endif
1385};
1386
1387#ifdef CONFIG_PPC_PMAC
1388
1389/*
1390 * Setup one port structure after probing, HW is down at this point,
1391 * Unlike sunzilog, we don't need to pre-init the spinlock as we don't
1392 * register our console before uart_add_one_port() is called
1393 */
1394static int __init pmz_init_port(struct uart_pmac_port *uap)
1395{
1396	struct device_node *np = uap->node;
1397	const char *conn;
1398	const struct slot_names_prop {
1399		int	count;
1400		char	name[1];
1401	} *slots;
1402	int len;
1403	struct resource r_ports, r_rxdma, r_txdma;
1404
1405	/*
1406	 * Request & map chip registers
1407	 */
1408	if (of_address_to_resource(np, 0, &r_ports))
1409		return -ENODEV;
1410	uap->port.mapbase = r_ports.start;
1411	uap->port.membase = ioremap(uap->port.mapbase, 0x1000);
1412
1413	uap->control_reg = uap->port.membase;
1414	uap->data_reg = uap->control_reg + 0x10;
1415	
1416	/*
1417	 * Request & map DBDMA registers
1418	 */
1419#ifdef HAS_DBDMA
1420	if (of_address_to_resource(np, 1, &r_txdma) == 0 &&
1421	    of_address_to_resource(np, 2, &r_rxdma) == 0)
1422		uap->flags |= PMACZILOG_FLAG_HAS_DMA;
1423#else
1424	memset(&r_txdma, 0, sizeof(struct resource));
1425	memset(&r_rxdma, 0, sizeof(struct resource));
1426#endif	
1427	if (ZS_HAS_DMA(uap)) {
1428		uap->tx_dma_regs = ioremap(r_txdma.start, 0x100);
1429		if (uap->tx_dma_regs == NULL) {	
1430			uap->flags &= ~PMACZILOG_FLAG_HAS_DMA;
1431			goto no_dma;
1432		}
1433		uap->rx_dma_regs = ioremap(r_rxdma.start, 0x100);
1434		if (uap->rx_dma_regs == NULL) {	
1435			iounmap(uap->tx_dma_regs);
1436			uap->tx_dma_regs = NULL;
1437			uap->flags &= ~PMACZILOG_FLAG_HAS_DMA;
1438			goto no_dma;
1439		}
1440		uap->tx_dma_irq = irq_of_parse_and_map(np, 1);
1441		uap->rx_dma_irq = irq_of_parse_and_map(np, 2);
1442	}
1443no_dma:
1444
1445	/*
1446	 * Detect port type
1447	 */
1448	if (of_device_is_compatible(np, "cobalt"))
1449		uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1450	conn = of_get_property(np, "AAPL,connector", &len);
1451	if (conn && (strcmp(conn, "infrared") == 0))
1452		uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1453	uap->port_type = PMAC_SCC_ASYNC;
1454	/* 1999 Powerbook G3 has slot-names property instead */
1455	slots = of_get_property(np, "slot-names", &len);
1456	if (slots && slots->count > 0) {
1457		if (strcmp(slots->name, "IrDA") == 0)
1458			uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1459		else if (strcmp(slots->name, "Modem") == 0)
1460			uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1461	}
1462	if (ZS_IS_IRDA(uap))
1463		uap->port_type = PMAC_SCC_IRDA;
1464	if (ZS_IS_INTMODEM(uap)) {
1465		struct device_node* i2c_modem =
1466			of_find_node_by_name(NULL, "i2c-modem");
1467		if (i2c_modem) {
1468			const char* mid =
1469				of_get_property(i2c_modem, "modem-id", NULL);
1470			if (mid) switch(*mid) {
1471			case 0x04 :
1472			case 0x05 :
1473			case 0x07 :
1474			case 0x08 :
1475			case 0x0b :
1476			case 0x0c :
1477				uap->port_type = PMAC_SCC_I2S1;
1478			}
1479			printk(KERN_INFO "pmac_zilog: i2c-modem detected, id: %d\n",
1480				mid ? (*mid) : 0);
1481			of_node_put(i2c_modem);
1482		} else {
1483			printk(KERN_INFO "pmac_zilog: serial modem detected\n");
1484		}
1485	}
1486
1487	/*
1488	 * Init remaining bits of "port" structure
1489	 */
1490	uap->port.iotype = UPIO_MEM;
1491	uap->port.irq = irq_of_parse_and_map(np, 0);
1492	uap->port.uartclk = ZS_CLOCK;
1493	uap->port.fifosize = 1;
1494	uap->port.ops = &pmz_pops;
1495	uap->port.type = PORT_PMAC_ZILOG;
1496	uap->port.flags = 0;
1497
1498	/*
1499	 * Fixup for the port on Gatwick for which the device-tree has
1500	 * missing interrupts. Normally, the macio_dev would contain
1501	 * fixed up interrupt info, but we use the device-tree directly
1502	 * here due to early probing so we need the fixup too.
1503	 */
1504	if (uap->port.irq == 0 &&
1505	    np->parent && np->parent->parent &&
1506	    of_device_is_compatible(np->parent->parent, "gatwick")) {
1507		/* IRQs on gatwick are offset by 64 */
1508		uap->port.irq = irq_create_mapping(NULL, 64 + 15);
1509		uap->tx_dma_irq = irq_create_mapping(NULL, 64 + 4);
1510		uap->rx_dma_irq = irq_create_mapping(NULL, 64 + 5);
1511	}
1512
1513	/* Setup some valid baud rate information in the register
1514	 * shadows so we don't write crap there before baud rate is
1515	 * first initialized.
1516	 */
1517	pmz_convert_to_zs(uap, CS8, 0, 9600);
1518
1519	return 0;
1520}
1521
1522/*
1523 * Get rid of a port on module removal
1524 */
1525static void pmz_dispose_port(struct uart_pmac_port *uap)
1526{
1527	struct device_node *np;
1528
1529	np = uap->node;
1530	iounmap(uap->rx_dma_regs);
1531	iounmap(uap->tx_dma_regs);
1532	iounmap(uap->control_reg);
1533	uap->node = NULL;
1534	of_node_put(np);
1535	memset(uap, 0, sizeof(struct uart_pmac_port));
1536}
1537
1538/*
1539 * Called upon match with an escc node in the device-tree.
1540 */
1541static int pmz_attach(struct macio_dev *mdev, const struct of_device_id *match)
1542{
1543	struct uart_pmac_port *uap;
1544	int i;
1545	
1546	/* Iterate the pmz_ports array to find a matching entry
1547	 */
1548	for (i = 0; i < MAX_ZS_PORTS; i++)
1549		if (pmz_ports[i].node == mdev->ofdev.dev.of_node)
1550			break;
1551	if (i >= MAX_ZS_PORTS)
1552		return -ENODEV;
1553
1554
1555	uap = &pmz_ports[i];
1556	uap->dev = mdev;
1557	uap->port.dev = &mdev->ofdev.dev;
1558	dev_set_drvdata(&mdev->ofdev.dev, uap);
1559
1560	/* We still activate the port even when failing to request resources
1561	 * to work around bugs in ancient Apple device-trees
1562	 */
1563	if (macio_request_resources(uap->dev, "pmac_zilog"))
1564		printk(KERN_WARNING "%pOFn: Failed to request resource"
1565		       ", port still active\n",
1566		       uap->node);
1567	else
1568		uap->flags |= PMACZILOG_FLAG_RSRC_REQUESTED;
1569
1570	return uart_add_one_port(&pmz_uart_reg, &uap->port);
1571}
1572
1573/*
1574 * That one should not be called, macio isn't really a hotswap device,
1575 * we don't expect one of those serial ports to go away...
1576 */
1577static int pmz_detach(struct macio_dev *mdev)
1578{
1579	struct uart_pmac_port	*uap = dev_get_drvdata(&mdev->ofdev.dev);
1580	
1581	if (!uap)
1582		return -ENODEV;
1583
1584	uart_remove_one_port(&pmz_uart_reg, &uap->port);
1585
1586	if (uap->flags & PMACZILOG_FLAG_RSRC_REQUESTED) {
1587		macio_release_resources(uap->dev);
1588		uap->flags &= ~PMACZILOG_FLAG_RSRC_REQUESTED;
1589	}
1590	dev_set_drvdata(&mdev->ofdev.dev, NULL);
1591	uap->dev = NULL;
1592	uap->port.dev = NULL;
1593	
1594	return 0;
1595}
1596
1597
1598static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
1599{
1600	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1601
1602	if (uap == NULL) {
1603		printk("HRM... pmz_suspend with NULL uap\n");
1604		return 0;
1605	}
1606
1607	uart_suspend_port(&pmz_uart_reg, &uap->port);
1608
1609	return 0;
1610}
1611
1612
1613static int pmz_resume(struct macio_dev *mdev)
1614{
1615	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1616
1617	if (uap == NULL)
1618		return 0;
1619
1620	uart_resume_port(&pmz_uart_reg, &uap->port);
1621
1622	return 0;
1623}
1624
1625/*
1626 * Probe all ports in the system and build the ports array, we register
1627 * with the serial layer later, so we get a proper struct device which
1628 * allows the tty to attach properly. This is later than it used to be
1629 * but the tty layer really wants it that way.
1630 */
1631static int __init pmz_probe(void)
1632{
1633	struct device_node	*node_p, *node_a, *node_b, *np;
1634	int			count = 0;
1635	int			rc;
1636
1637	/*
1638	 * Find all escc chips in the system
1639	 */
1640	for_each_node_by_name(node_p, "escc") {
1641		/*
1642		 * First get channel A/B node pointers
1643		 * 
1644		 * TODO: Add routines with proper locking to do that...
1645		 */
1646		node_a = node_b = NULL;
1647		for_each_child_of_node(node_p, np) {
1648			if (of_node_name_prefix(np, "ch-a"))
1649				node_a = of_node_get(np);
1650			else if (of_node_name_prefix(np, "ch-b"))
1651				node_b = of_node_get(np);
1652		}
1653		if (!node_a && !node_b) {
1654			of_node_put(node_a);
1655			of_node_put(node_b);
1656			printk(KERN_ERR "pmac_zilog: missing node %c for escc %pOF\n",
1657				(!node_a) ? 'a' : 'b', node_p);
1658			continue;
1659		}
1660
1661		/*
1662		 * Fill basic fields in the port structures
1663		 */
1664		if (node_b != NULL) {
1665			pmz_ports[count].mate		= &pmz_ports[count+1];
1666			pmz_ports[count+1].mate		= &pmz_ports[count];
1667		}
1668		pmz_ports[count].flags		= PMACZILOG_FLAG_IS_CHANNEL_A;
1669		pmz_ports[count].node		= node_a;
1670		pmz_ports[count+1].node		= node_b;
1671		pmz_ports[count].port.line	= count;
1672		pmz_ports[count+1].port.line	= count+1;
1673
1674		/*
1675		 * Setup the ports for real
1676		 */
1677		rc = pmz_init_port(&pmz_ports[count]);
1678		if (rc == 0 && node_b != NULL)
1679			rc = pmz_init_port(&pmz_ports[count+1]);
1680		if (rc != 0) {
1681			of_node_put(node_a);
1682			of_node_put(node_b);
1683			memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));
1684			memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));
1685			continue;
1686		}
1687		count += 2;
1688	}
1689	pmz_ports_count = count;
1690
1691	return 0;
1692}
1693
1694#else
1695
1696/* On PCI PowerMacs, pmz_probe() does an explicit search of the OpenFirmware
1697 * tree to obtain the device_nodes needed to start the console before the
1698 * macio driver. On Macs without OpenFirmware, global platform_devices take
1699 * the place of those device_nodes.
1700 */
1701extern struct platform_device scc_a_pdev, scc_b_pdev;
1702
1703static int __init pmz_init_port(struct uart_pmac_port *uap)
1704{
1705	struct resource *r_ports, *r_irq;
 
1706
1707	r_ports = platform_get_resource(uap->pdev, IORESOURCE_MEM, 0);
1708	r_irq = platform_get_resource(uap->pdev, IORESOURCE_IRQ, 0);
1709	if (!r_ports || !r_irq)
1710		return -ENODEV;
1711
 
 
 
 
1712	uap->port.mapbase  = r_ports->start;
1713	uap->port.membase  = (unsigned char __iomem *) r_ports->start;
1714	uap->port.iotype   = UPIO_MEM;
1715	uap->port.irq      = r_irq->start;
1716	uap->port.uartclk  = ZS_CLOCK;
1717	uap->port.fifosize = 1;
1718	uap->port.ops      = &pmz_pops;
1719	uap->port.type     = PORT_PMAC_ZILOG;
1720	uap->port.flags    = 0;
1721
1722	uap->control_reg   = uap->port.membase;
1723	uap->data_reg      = uap->control_reg + 4;
1724	uap->port_type     = 0;
1725	uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_PMACZILOG_CONSOLE);
1726
1727	pmz_convert_to_zs(uap, CS8, 0, 9600);
1728
1729	return 0;
1730}
1731
1732static int __init pmz_probe(void)
1733{
1734	int err;
1735
1736	pmz_ports_count = 0;
1737
1738	pmz_ports[0].port.line = 0;
1739	pmz_ports[0].flags     = PMACZILOG_FLAG_IS_CHANNEL_A;
1740	pmz_ports[0].pdev      = &scc_a_pdev;
1741	err = pmz_init_port(&pmz_ports[0]);
1742	if (err)
1743		return err;
1744	pmz_ports_count++;
1745
1746	pmz_ports[0].mate      = &pmz_ports[1];
1747	pmz_ports[1].mate      = &pmz_ports[0];
1748	pmz_ports[1].port.line = 1;
1749	pmz_ports[1].flags     = 0;
1750	pmz_ports[1].pdev      = &scc_b_pdev;
1751	err = pmz_init_port(&pmz_ports[1]);
1752	if (err)
1753		return err;
1754	pmz_ports_count++;
1755
1756	return 0;
1757}
1758
1759static void pmz_dispose_port(struct uart_pmac_port *uap)
1760{
1761	memset(uap, 0, sizeof(struct uart_pmac_port));
1762}
1763
1764static int __init pmz_attach(struct platform_device *pdev)
1765{
1766	struct uart_pmac_port *uap;
1767	int i;
1768
1769	/* Iterate the pmz_ports array to find a matching entry */
1770	for (i = 0; i < pmz_ports_count; i++)
1771		if (pmz_ports[i].pdev == pdev)
1772			break;
1773	if (i >= pmz_ports_count)
1774		return -ENODEV;
1775
1776	uap = &pmz_ports[i];
1777	uap->port.dev = &pdev->dev;
1778	platform_set_drvdata(pdev, uap);
1779
1780	return uart_add_one_port(&pmz_uart_reg, &uap->port);
1781}
1782
1783static int __exit pmz_detach(struct platform_device *pdev)
1784{
1785	struct uart_pmac_port *uap = platform_get_drvdata(pdev);
1786
1787	if (!uap)
1788		return -ENODEV;
1789
1790	uart_remove_one_port(&pmz_uart_reg, &uap->port);
1791
1792	uap->port.dev = NULL;
1793
1794	return 0;
1795}
1796
1797#endif /* !CONFIG_PPC_PMAC */
1798
1799#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1800
1801static void pmz_console_write(struct console *con, const char *s, unsigned int count);
1802static int __init pmz_console_setup(struct console *co, char *options);
1803
1804static struct console pmz_console = {
1805	.name	=	PMACZILOG_NAME,
1806	.write	=	pmz_console_write,
1807	.device	=	uart_console_device,
1808	.setup	=	pmz_console_setup,
1809	.flags	=	CON_PRINTBUFFER,
1810	.index	=	-1,
1811	.data   =	&pmz_uart_reg,
1812};
1813
1814#define PMACZILOG_CONSOLE	&pmz_console
1815#else /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1816#define PMACZILOG_CONSOLE	(NULL)
1817#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1818
1819/*
1820 * Register the driver, console driver and ports with the serial
1821 * core
1822 */
1823static int __init pmz_register(void)
1824{
1825	pmz_uart_reg.nr = pmz_ports_count;
1826	pmz_uart_reg.cons = PMACZILOG_CONSOLE;
1827
1828	/*
1829	 * Register this driver with the serial core
1830	 */
1831	return uart_register_driver(&pmz_uart_reg);
1832}
1833
1834#ifdef CONFIG_PPC_PMAC
1835
1836static const struct of_device_id pmz_match[] =
1837{
1838	{
1839	.name		= "ch-a",
1840	},
1841	{
1842	.name		= "ch-b",
1843	},
1844	{},
1845};
1846MODULE_DEVICE_TABLE (of, pmz_match);
1847
1848static struct macio_driver pmz_driver = {
1849	.driver = {
1850		.name 		= "pmac_zilog",
1851		.owner		= THIS_MODULE,
1852		.of_match_table	= pmz_match,
1853	},
1854	.probe		= pmz_attach,
1855	.remove		= pmz_detach,
1856	.suspend	= pmz_suspend,
1857	.resume		= pmz_resume,
1858};
1859
1860#else
1861
1862static struct platform_driver pmz_driver = {
1863	.remove		= __exit_p(pmz_detach),
1864	.driver		= {
1865		.name		= "scc",
1866	},
1867};
1868
1869#endif /* !CONFIG_PPC_PMAC */
1870
1871static int __init init_pmz(void)
1872{
1873	int rc, i;
1874	printk(KERN_INFO "%s\n", version);
1875
1876	/* 
1877	 * First, we need to do a direct OF-based probe pass. We
1878	 * do that because we want serial console up before the
1879	 * macio stuffs calls us back, and since that makes it
1880	 * easier to pass the proper number of channels to
1881	 * uart_register_driver()
1882	 */
1883	if (pmz_ports_count == 0)
1884		pmz_probe();
1885
1886	/*
1887	 * Bail early if no port found
1888	 */
1889	if (pmz_ports_count == 0)
1890		return -ENODEV;
1891
1892	/*
1893	 * Now we register with the serial layer
1894	 */
1895	rc = pmz_register();
1896	if (rc) {
1897		printk(KERN_ERR 
1898			"pmac_zilog: Error registering serial device, disabling pmac_zilog.\n"
1899		 	"pmac_zilog: Did another serial driver already claim the minors?\n"); 
1900		/* effectively "pmz_unprobe()" */
1901		for (i=0; i < pmz_ports_count; i++)
1902			pmz_dispose_port(&pmz_ports[i]);
1903		return rc;
1904	}
1905
1906	/*
1907	 * Then we register the macio driver itself
1908	 */
1909#ifdef CONFIG_PPC_PMAC
1910	return macio_register_driver(&pmz_driver);
1911#else
1912	return platform_driver_probe(&pmz_driver, pmz_attach);
1913#endif
1914}
1915
1916static void __exit exit_pmz(void)
1917{
1918	int i;
1919
1920#ifdef CONFIG_PPC_PMAC
1921	/* Get rid of macio-driver (detach from macio) */
1922	macio_unregister_driver(&pmz_driver);
1923#else
1924	platform_driver_unregister(&pmz_driver);
1925#endif
1926
1927	for (i = 0; i < pmz_ports_count; i++) {
1928		struct uart_pmac_port *uport = &pmz_ports[i];
1929#ifdef CONFIG_PPC_PMAC
1930		if (uport->node != NULL)
1931			pmz_dispose_port(uport);
1932#else
1933		if (uport->pdev != NULL)
1934			pmz_dispose_port(uport);
1935#endif
1936	}
1937	/* Unregister UART driver */
1938	uart_unregister_driver(&pmz_uart_reg);
1939}
1940
1941#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1942
1943static void pmz_console_putchar(struct uart_port *port, int ch)
1944{
1945	struct uart_pmac_port *uap =
1946		container_of(port, struct uart_pmac_port, port);
1947
1948	/* Wait for the transmit buffer to empty. */
1949	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1950		udelay(5);
1951	write_zsdata(uap, ch);
1952}
1953
1954/*
1955 * Print a string to the serial port trying not to disturb
1956 * any possible real use of the port...
1957 */
1958static void pmz_console_write(struct console *con, const char *s, unsigned int count)
1959{
1960	struct uart_pmac_port *uap = &pmz_ports[con->index];
1961	unsigned long flags;
1962
1963	spin_lock_irqsave(&uap->port.lock, flags);
1964
1965	/* Turn of interrupts and enable the transmitter. */
1966	write_zsreg(uap, R1, uap->curregs[1] & ~TxINT_ENAB);
1967	write_zsreg(uap, R5, uap->curregs[5] | TxENABLE | RTS | DTR);
1968
1969	uart_console_write(&uap->port, s, count, pmz_console_putchar);
1970
1971	/* Restore the values in the registers. */
1972	write_zsreg(uap, R1, uap->curregs[1]);
1973	/* Don't disable the transmitter. */
1974
1975	spin_unlock_irqrestore(&uap->port.lock, flags);
1976}
1977
1978/*
1979 * Setup the serial console
1980 */
1981static int __init pmz_console_setup(struct console *co, char *options)
1982{
1983	struct uart_pmac_port *uap;
1984	struct uart_port *port;
1985	int baud = 38400;
1986	int bits = 8;
1987	int parity = 'n';
1988	int flow = 'n';
1989	unsigned long pwr_delay;
1990
1991	/*
1992	 * XServe's default to 57600 bps
1993	 */
1994	if (of_machine_is_compatible("RackMac1,1")
1995	    || of_machine_is_compatible("RackMac1,2")
1996	    || of_machine_is_compatible("MacRISC4"))
1997		baud = 57600;
1998
1999	/*
2000	 * Check whether an invalid uart number has been specified, and
2001	 * if so, search for the first available port that does have
2002	 * console support.
2003	 */
2004	if (co->index >= pmz_ports_count)
2005		co->index = 0;
2006	uap = &pmz_ports[co->index];
2007#ifdef CONFIG_PPC_PMAC
2008	if (uap->node == NULL)
2009		return -ENODEV;
2010#else
2011	if (uap->pdev == NULL)
2012		return -ENODEV;
2013#endif
2014	port = &uap->port;
2015
2016	/*
2017	 * Mark port as beeing a console
2018	 */
2019	uap->flags |= PMACZILOG_FLAG_IS_CONS;
2020
2021	/*
2022	 * Temporary fix for uart layer who didn't setup the spinlock yet
2023	 */
2024	spin_lock_init(&port->lock);
2025
2026	/*
2027	 * Enable the hardware
2028	 */
2029	pwr_delay = __pmz_startup(uap);
2030	if (pwr_delay)
2031		mdelay(pwr_delay);
2032	
2033	if (options)
2034		uart_parse_options(options, &baud, &parity, &bits, &flow);
2035
2036	return uart_set_options(port, co, baud, parity, bits, flow);
2037}
2038
2039static int __init pmz_console_init(void)
2040{
2041	/* Probe ports */
2042	pmz_probe();
2043
2044	if (pmz_ports_count == 0)
2045		return -ENODEV;
2046
2047	/* TODO: Autoprobe console based on OF */
2048	/* pmz_console.index = i; */
2049	register_console(&pmz_console);
2050
2051	return 0;
2052
2053}
2054console_initcall(pmz_console_init);
2055#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
2056
2057module_init(init_pmz);
2058module_exit(exit_pmz);