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1// SPDX-License-Identifier: GPL-2.0+2/*3 * Driver for PowerMac Z85c30 based ESCC cell found in the4 * "macio" ASICs of various PowerMac models5 * 6 * Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org)7 *8 * Derived from drivers/macintosh/macserial.c by Paul Mackerras9 * and drivers/serial/sunzilog.c by David S. Miller10 *11 * Hrm... actually, I ripped most of sunzilog (Thanks David !) and12 * adapted special tweaks needed for us. I don't think it's worth13 * merging back those though. The DMA code still has to get in14 * and once done, I expect that driver to remain fairly stable in15 * the long term, unless we change the driver model again...16 *17 * 2004-08-06 Harald Welte <laforge@gnumonks.org>18 *	- Enable BREAK interrupt19 *	- Add support for sysreq20 *21 * TODO:   - Add DMA support22 *         - Defer port shutdown to a few seconds after close23 *         - maybe put something right into uap->clk_divisor24 */25 26#undef DEBUG27#undef USE_CTRL_O_SYSRQ28 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_PMAC53#include <asm/machdep.h>54#include <asm/pmac_feature.h>55#include <asm/macio.h>56#else57#include <linux/platform_device.h>58#define of_machine_is_compatible(x) (0)59#endif60 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_TTYS71#define PMACZILOG_MAJOR		TTY_MAJOR72#define PMACZILOG_MINOR		6473#define PMACZILOG_NAME		"ttyS"74#else75#define PMACZILOG_MAJOR		20476#define PMACZILOG_MINOR		19277#define PMACZILOG_NAME		"ttyPZ"78#endif79 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-probe86 * (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 port102 * This function must only be called when the TX is not busy.  The UART103 * 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 Tx178 * Reprogram the Zilog channel HW registers with the copies found in the179 * software state struct.  If the transmitter is busy, we defer this update180 * 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;213 214	/* Sanity check, make sure the old bug is no longer happening */215	if (uap->port.state == NULL) {216		WARN_ON(1);217		(void)read_zsdata(uap);218		return false;219	}220	port = &uap->port.state->port;221 222	while (1) {223		drop = 0;224 225		r1 = read_zsreg(uap, R1);226		ch = read_zsdata(uap);227 228		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {229			write_zsreg(uap, R0, ERR_RES);230			zssync(uap);231		}232 233		ch &= uap->parity_mask;234		if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {235			uap->flags &= ~PMACZILOG_FLAG_BREAK;236		}237 238#if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)239#ifdef USE_CTRL_O_SYSRQ240		/* Handle the SysRq ^O Hack */241		if (ch == '\x0f') {242			uap->port.sysrq = jiffies + HZ*5;243			goto next_char;244		}245#endif /* USE_CTRL_O_SYSRQ */246		if (uap->port.sysrq) {247			int swallow;248			uart_port_unlock(&uap->port);249			swallow = uart_handle_sysrq_char(&uap->port, ch);250			uart_port_lock(&uap->port);251			if (swallow)252				goto next_char;253		}254#endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */255 256		/* A real serial line, record the character and status.  */257		if (drop)258			goto next_char;259 260		flag = TTY_NORMAL;261		uap->port.icount.rx++;262 263		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {264			if (r1 & BRK_ABRT) {265				pmz_debug("pmz: got break !\n");266				r1 &= ~(PAR_ERR | CRC_ERR);267				uap->port.icount.brk++;268				if (uart_handle_break(&uap->port))269					goto next_char;270			}271			else if (r1 & PAR_ERR)272				uap->port.icount.parity++;273			else if (r1 & CRC_ERR)274				uap->port.icount.frame++;275			if (r1 & Rx_OVR)276				uap->port.icount.overrun++;277			r1 &= uap->port.read_status_mask;278			if (r1 & BRK_ABRT)279				flag = TTY_BREAK;280			else if (r1 & PAR_ERR)281				flag = TTY_PARITY;282			else if (r1 & CRC_ERR)283				flag = TTY_FRAME;284		}285 286		if (uap->port.ignore_status_mask == 0xff ||287		    (r1 & uap->port.ignore_status_mask) == 0) {288			tty_insert_flip_char(port, ch, flag);289		}290		if (r1 & Rx_OVR)291			tty_insert_flip_char(port, 0, TTY_OVERRUN);292	next_char:293		ch = read_zsreg(uap, R0);294		if (!(ch & Rx_CH_AV))295			break;296	}297 298	return true;299}300 301static void pmz_status_handle(struct uart_pmac_port *uap)302{303	unsigned char status;304 305	status = read_zsreg(uap, R0);306	write_zsreg(uap, R0, RES_EXT_INT);307	zssync(uap);308 309	if (ZS_IS_OPEN(uap) && ZS_WANTS_MODEM_STATUS(uap)) {310		if (status & SYNC_HUNT)311			uap->port.icount.dsr++;312 313		/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.314		 * But it does not tell us which bit has changed, we have to keep315		 * track of this ourselves.316		 * The CTS input is inverted for some reason.  -- paulus317		 */318		if ((status ^ uap->prev_status) & DCD)319			uart_handle_dcd_change(&uap->port,320					       (status & DCD));321		if ((status ^ uap->prev_status) & CTS)322			uart_handle_cts_change(&uap->port,323					       !(status & CTS));324 325		wake_up_interruptible(&uap->port.state->port.delta_msr_wait);326	}327 328	if (status & BRK_ABRT)329		uap->flags |= PMACZILOG_FLAG_BREAK;330 331	uap->prev_status = status;332}333 334static void pmz_transmit_chars(struct uart_pmac_port *uap)335{336	struct tty_port *tport;337	unsigned char ch;338 339	if (ZS_IS_CONS(uap)) {340		unsigned char status = read_zsreg(uap, R0);341 342		/* TX still busy?  Just wait for the next TX done interrupt.343		 *344		 * It can occur because of how we do serial console writes.  It would345		 * be nice to transmit console writes just like we normally would for346		 * a TTY line. (ie. buffered and TX interrupt driven).  That is not347		 * easy because console writes cannot sleep.  One solution might be348		 * to poll on enough port->xmit space becoming free.  -DaveM349		 */350		if (!(status & Tx_BUF_EMP))351			return;352	}353 354	uap->flags &= ~PMACZILOG_FLAG_TX_ACTIVE;355 356	if (ZS_REGS_HELD(uap)) {357		pmz_load_zsregs(uap, uap->curregs);358		uap->flags &= ~PMACZILOG_FLAG_REGS_HELD;359	}360 361	if (ZS_TX_STOPPED(uap)) {362		uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;363		goto ack_tx_int;364	}365 366	/* Under some circumstances, we see interrupts reported for367	 * a closed channel. The interrupt mask in R1 is clear, but368	 * R3 still signals the interrupts and we see them when taking369	 * an interrupt for the other channel (this could be a qemu370	 * bug but since the ESCC doc doesn't specify precsiely whether371	 * R3 interrup status bits are masked by R1 interrupt enable372	 * bits, better safe than sorry). --BenH.373	 */374	if (!ZS_IS_OPEN(uap))375		goto ack_tx_int;376 377	if (uap->port.x_char) {378		uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;379		write_zsdata(uap, uap->port.x_char);380		zssync(uap);381		uap->port.icount.tx++;382		uap->port.x_char = 0;383		return;384	}385 386	if (uap->port.state == NULL)387		goto ack_tx_int;388	tport = &uap->port.state->port;389	if (kfifo_is_empty(&tport->xmit_fifo)) {390		uart_write_wakeup(&uap->port);391		goto ack_tx_int;392	}393	if (uart_tx_stopped(&uap->port))394		goto ack_tx_int;395 396	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;397	WARN_ON(!uart_fifo_get(&uap->port, &ch));398	write_zsdata(uap, ch);399	zssync(uap);400 401	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)402		uart_write_wakeup(&uap->port);403 404	return;405 406ack_tx_int:407	write_zsreg(uap, R0, RES_Tx_P);408	zssync(uap);409}410 411/* Hrm... we register that twice, fixme later.... */412static irqreturn_t pmz_interrupt(int irq, void *dev_id)413{414	struct uart_pmac_port *uap = dev_id;415	struct uart_pmac_port *uap_a;416	struct uart_pmac_port *uap_b;417	int rc = IRQ_NONE;418	bool push;419	u8 r3;420 421	uap_a = pmz_get_port_A(uap);422	uap_b = uap_a->mate;423 424	uart_port_lock(&uap_a->port);425	r3 = read_zsreg(uap_a, R3);426 427	/* Channel A */428	push = false;429	if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {430		if (!ZS_IS_OPEN(uap_a)) {431			pmz_debug("ChanA interrupt while not open !\n");432			goto skip_a;433		}434		write_zsreg(uap_a, R0, RES_H_IUS);435		zssync(uap_a);		436		if (r3 & CHAEXT)437			pmz_status_handle(uap_a);438		if (r3 & CHARxIP)439			push = pmz_receive_chars(uap_a);440		if (r3 & CHATxIP)441			pmz_transmit_chars(uap_a);442		rc = IRQ_HANDLED;443	}444 skip_a:445	uart_port_unlock(&uap_a->port);446	if (push)447		tty_flip_buffer_push(&uap->port.state->port);448 449	if (!uap_b)450		goto out;451 452	uart_port_lock(&uap_b->port);453	push = false;454	if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {455		if (!ZS_IS_OPEN(uap_b)) {456			pmz_debug("ChanB interrupt while not open !\n");457			goto skip_b;458		}459		write_zsreg(uap_b, R0, RES_H_IUS);460		zssync(uap_b);461		if (r3 & CHBEXT)462			pmz_status_handle(uap_b);463		if (r3 & CHBRxIP)464			push = pmz_receive_chars(uap_b);465		if (r3 & CHBTxIP)466			pmz_transmit_chars(uap_b);467		rc = IRQ_HANDLED;468	}469 skip_b:470	uart_port_unlock(&uap_b->port);471	if (push)472		tty_flip_buffer_push(&uap->port.state->port);473 474 out:475	return rc;476}477 478/*479 * Peek the status register, lock not held by caller480 */481static inline u8 pmz_peek_status(struct uart_pmac_port *uap)482{483	unsigned long flags;484	u8 status;485	486	uart_port_lock_irqsave(&uap->port, &flags);487	status = read_zsreg(uap, R0);488	uart_port_unlock_irqrestore(&uap->port, flags);489 490	return status;491}492 493/* 494 * Check if transmitter is empty495 * The port lock is not held.496 */497static unsigned int pmz_tx_empty(struct uart_port *port)498{499	unsigned char status;500 501	status = pmz_peek_status(to_pmz(port));502	if (status & Tx_BUF_EMP)503		return TIOCSER_TEMT;504	return 0;505}506 507/* 508 * Set Modem Control (RTS & DTR) bits509 * The port lock is held and interrupts are disabled.510 * Note: Shall we really filter out RTS on external ports or511 * should that be dealt at higher level only ?512 */513static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)514{515	struct uart_pmac_port *uap = to_pmz(port);516	unsigned char set_bits, clear_bits;517 518        /* Do nothing for irda for now... */519	if (ZS_IS_IRDA(uap))520		return;521	/* We get called during boot with a port not up yet */522	if (!(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))523		return;524 525	set_bits = clear_bits = 0;526 527	if (ZS_IS_INTMODEM(uap)) {528		if (mctrl & TIOCM_RTS)529			set_bits |= RTS;530		else531			clear_bits |= RTS;532	}533	if (mctrl & TIOCM_DTR)534		set_bits |= DTR;535	else536		clear_bits |= DTR;537 538	/* NOTE: Not subject to 'transmitter active' rule.  */ 539	uap->curregs[R5] |= set_bits;540	uap->curregs[R5] &= ~clear_bits;541 542	write_zsreg(uap, R5, uap->curregs[R5]);543	pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",544		  set_bits, clear_bits, uap->curregs[R5]);545	zssync(uap);546}547 548/* 549 * Get Modem Control bits (only the input ones, the core will550 * or that with a cached value of the control ones)551 * The port lock is held and interrupts are disabled.552 */553static unsigned int pmz_get_mctrl(struct uart_port *port)554{555	struct uart_pmac_port *uap = to_pmz(port);556	unsigned char status;557	unsigned int ret;558 559	status = read_zsreg(uap, R0);560 561	ret = 0;562	if (status & DCD)563		ret |= TIOCM_CAR;564	if (status & SYNC_HUNT)565		ret |= TIOCM_DSR;566	if (!(status & CTS))567		ret |= TIOCM_CTS;568 569	return ret;570}571 572/* 573 * Stop TX side. Dealt like sunzilog at next Tx interrupt,574 * though for DMA, we will have to do a bit more.575 * The port lock is held and interrupts are disabled.576 */577static void pmz_stop_tx(struct uart_port *port)578{579	to_pmz(port)->flags |= PMACZILOG_FLAG_TX_STOPPED;580}581 582/* 583 * Kick the Tx side.584 * The port lock is held and interrupts are disabled.585 */586static void pmz_start_tx(struct uart_port *port)587{588	struct uart_pmac_port *uap = to_pmz(port);589	unsigned char status;590 591	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;592	uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;593 594	status = read_zsreg(uap, R0);595 596	/* TX busy?  Just wait for the TX done interrupt.  */597	if (!(status & Tx_BUF_EMP))598		return;599 600	/* Send the first character to jump-start the TX done601	 * IRQ sending engine.602	 */603	if (port->x_char) {604		write_zsdata(uap, port->x_char);605		zssync(uap);606		port->icount.tx++;607		port->x_char = 0;608	} else {609		struct tty_port *tport = &port->state->port;610		unsigned char ch;611 612		if (!uart_fifo_get(&uap->port, &ch))613			return;614		write_zsdata(uap, ch);615		zssync(uap);616 617		if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)618			uart_write_wakeup(&uap->port);619	}620}621 622/* 623 * Stop Rx side, basically disable emitting of624 * Rx interrupts on the port. We don't disable the rx625 * side of the chip proper though626 * The port lock is held.627 */628static void pmz_stop_rx(struct uart_port *port)629{630	struct uart_pmac_port *uap = to_pmz(port);631 632	/* Disable all RX interrupts.  */633	uap->curregs[R1] &= ~RxINT_MASK;634	pmz_maybe_update_regs(uap);635}636 637/* 638 * Enable modem status change interrupts639 * The port lock is held.640 */641static void pmz_enable_ms(struct uart_port *port)642{643	struct uart_pmac_port *uap = to_pmz(port);644	unsigned char new_reg;645 646	if (ZS_IS_IRDA(uap))647		return;648	new_reg = uap->curregs[R15] | (DCDIE | SYNCIE | CTSIE);649	if (new_reg != uap->curregs[R15]) {650		uap->curregs[R15] = new_reg;651 652		/* NOTE: Not subject to 'transmitter active' rule. */653		write_zsreg(uap, R15, uap->curregs[R15]);654	}655}656 657/* 658 * Control break state emission659 * The port lock is not held.660 */661static void pmz_break_ctl(struct uart_port *port, int break_state)662{663	struct uart_pmac_port *uap = to_pmz(port);664	unsigned char set_bits, clear_bits, new_reg;665	unsigned long flags;666 667	set_bits = clear_bits = 0;668 669	if (break_state)670		set_bits |= SND_BRK;671	else672		clear_bits |= SND_BRK;673 674	uart_port_lock_irqsave(port, &flags);675 676	new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits;677	if (new_reg != uap->curregs[R5]) {678		uap->curregs[R5] = new_reg;679		write_zsreg(uap, R5, uap->curregs[R5]);680	}681 682	uart_port_unlock_irqrestore(port, flags);683}684 685#ifdef CONFIG_PPC_PMAC686 687/*688 * Turn power on or off to the SCC and associated stuff689 * (port drivers, modem, IR port, etc.)690 * Returns the number of milliseconds we should wait before691 * trying to use the port.692 */693static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)694{695	int delay = 0;696	int rc;697 698	if (state) {699		rc = pmac_call_feature(700			PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);701		pmz_debug("port power on result: %d\n", rc);702		if (ZS_IS_INTMODEM(uap)) {703			rc = pmac_call_feature(704				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);705			delay = 2500;	/* wait for 2.5s before using */706			pmz_debug("modem power result: %d\n", rc);707		}708	} else {709		/* TODO: Make that depend on a timer, don't power down710		 * immediately711		 */712		if (ZS_IS_INTMODEM(uap)) {713			rc = pmac_call_feature(714				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);715			pmz_debug("port power off result: %d\n", rc);716		}717		pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);718	}719	return delay;720}721 722#else723 724static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)725{726	return 0;727}728 729#endif /* !CONFIG_PPC_PMAC */730 731/*732 * FixZeroBug....Works around a bug in the SCC receiving channel.733 * Inspired from Darwin code, 15 Sept. 2000  -DanM734 *735 * The following sequence prevents a problem that is seen with O'Hare ASICs736 * (most versions -- also with some Heathrow and Hydra ASICs) where a zero737 * at the input to the receiver becomes 'stuck' and locks up the receiver.738 * This problem can occur as a result of a zero bit at the receiver input739 * coincident with any of the following events:740 *741 *	The SCC is initialized (hardware or software).742 *	A framing error is detected.743 *	The clocking option changes from synchronous or X1 asynchronous744 *		clocking to X16, X32, or X64 asynchronous clocking.745 *	The decoding mode is changed among NRZ, NRZI, FM0, or FM1.746 *747 * This workaround attempts to recover from the lockup condition by placing748 * the SCC in synchronous loopback mode with a fast clock before programming749 * any of the asynchronous modes.750 */751static void pmz_fix_zero_bug_scc(struct uart_pmac_port *uap)752{753	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);754	zssync(uap);755	udelay(10);756	write_zsreg(uap, 9, (ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB) | NV);757	zssync(uap);758 759	write_zsreg(uap, 4, X1CLK | MONSYNC);760	write_zsreg(uap, 3, Rx8);761	write_zsreg(uap, 5, Tx8 | RTS);762	write_zsreg(uap, 9, NV);	/* Didn't we already do this? */763	write_zsreg(uap, 11, RCBR | TCBR);764	write_zsreg(uap, 12, 0);765	write_zsreg(uap, 13, 0);766	write_zsreg(uap, 14, (LOOPBAK | BRSRC));767	write_zsreg(uap, 14, (LOOPBAK | BRSRC | BRENAB));768	write_zsreg(uap, 3, Rx8 | RxENABLE);769	write_zsreg(uap, 0, RES_EXT_INT);770	write_zsreg(uap, 0, RES_EXT_INT);771	write_zsreg(uap, 0, RES_EXT_INT);	/* to kill some time */772 773	/* The channel should be OK now, but it is probably receiving774	 * loopback garbage.775	 * Switch to asynchronous mode, disable the receiver,776	 * and discard everything in the receive buffer.777	 */778	write_zsreg(uap, 9, NV);779	write_zsreg(uap, 4, X16CLK | SB_MASK);780	write_zsreg(uap, 3, Rx8);781 782	while (read_zsreg(uap, 0) & Rx_CH_AV) {783		(void)read_zsreg(uap, 8);784		write_zsreg(uap, 0, RES_EXT_INT);785		write_zsreg(uap, 0, ERR_RES);786	}787}788 789/*790 * Real startup routine, powers up the hardware and sets up791 * the SCC. Returns a delay in ms where you need to wait before792 * actually using the port, this is typically the internal modem793 * powerup delay. This routine expect the lock to be taken.794 */795static int __pmz_startup(struct uart_pmac_port *uap)796{797	int pwr_delay = 0;798 799	memset(&uap->curregs, 0, sizeof(uap->curregs));800 801	/* Power up the SCC & underlying hardware (modem/irda) */802	pwr_delay = pmz_set_scc_power(uap, 1);803 804	/* Nice buggy HW ... */805	pmz_fix_zero_bug_scc(uap);806 807	/* Reset the channel */808	uap->curregs[R9] = 0;809	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);810	zssync(uap);811	udelay(10);812	write_zsreg(uap, 9, 0);813	zssync(uap);814 815	/* Clear the interrupt registers */816	write_zsreg(uap, R1, 0);817	write_zsreg(uap, R0, ERR_RES);818	write_zsreg(uap, R0, ERR_RES);819	write_zsreg(uap, R0, RES_H_IUS);820	write_zsreg(uap, R0, RES_H_IUS);821 822	/* Setup some valid baud rate */823	uap->curregs[R4] = X16CLK | SB1;824	uap->curregs[R3] = Rx8;825	uap->curregs[R5] = Tx8 | RTS;826	if (!ZS_IS_IRDA(uap))827		uap->curregs[R5] |= DTR;828	uap->curregs[R12] = 0;829	uap->curregs[R13] = 0;830	uap->curregs[R14] = BRENAB;831 832	/* Clear handshaking, enable BREAK interrupts */833	uap->curregs[R15] = BRKIE;834 835	/* Master interrupt enable */836	uap->curregs[R9] |= NV | MIE;837 838	pmz_load_zsregs(uap, uap->curregs);839 840	/* Enable receiver and transmitter.  */841	write_zsreg(uap, R3, uap->curregs[R3] |= RxENABLE);842	write_zsreg(uap, R5, uap->curregs[R5] |= TxENABLE);843 844	/* Remember status for DCD/CTS changes */845	uap->prev_status = read_zsreg(uap, R0);846 847	return pwr_delay;848}849 850static void pmz_irda_reset(struct uart_pmac_port *uap)851{852	unsigned long flags;853 854	uart_port_lock_irqsave(&uap->port, &flags);855	uap->curregs[R5] |= DTR;856	write_zsreg(uap, R5, uap->curregs[R5]);857	zssync(uap);858	uart_port_unlock_irqrestore(&uap->port, flags);859	msleep(110);860 861	uart_port_lock_irqsave(&uap->port, &flags);862	uap->curregs[R5] &= ~DTR;863	write_zsreg(uap, R5, uap->curregs[R5]);864	zssync(uap);865	uart_port_unlock_irqrestore(&uap->port, flags);866	msleep(10);867}868 869/*870 * This is the "normal" startup routine, using the above one871 * wrapped with the lock and doing a schedule delay872 */873static int pmz_startup(struct uart_port *port)874{875	struct uart_pmac_port *uap = to_pmz(port);876	unsigned long flags;877	int pwr_delay = 0;878 879	uap->flags |= PMACZILOG_FLAG_IS_OPEN;880 881	/* A console is never powered down. Else, power up and882	 * initialize the chip883	 */884	if (!ZS_IS_CONS(uap)) {885		uart_port_lock_irqsave(port, &flags);886		pwr_delay = __pmz_startup(uap);887		uart_port_unlock_irqrestore(port, flags);888	}	889	sprintf(uap->irq_name, PMACZILOG_NAME"%d", uap->port.line);890	if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED,891			uap->irq_name, uap)) {892		pmz_error("Unable to register zs interrupt handler.\n");893		pmz_set_scc_power(uap, 0);894		return -ENXIO;895	}896 897	/* Right now, we deal with delay by blocking here, I'll be898	 * smarter later on899	 */900	if (pwr_delay != 0) {901		pmz_debug("pmz: delaying %d ms\n", pwr_delay);902		msleep(pwr_delay);903	}904 905	/* IrDA reset is done now */906	if (ZS_IS_IRDA(uap))907		pmz_irda_reset(uap);908 909	/* Enable interrupt requests for the channel */910	uart_port_lock_irqsave(port, &flags);911	pmz_interrupt_control(uap, 1);912	uart_port_unlock_irqrestore(port, flags);913 914	return 0;915}916 917static void pmz_shutdown(struct uart_port *port)918{919	struct uart_pmac_port *uap = to_pmz(port);920	unsigned long flags;921 922	uart_port_lock_irqsave(port, &flags);923 924	/* Disable interrupt requests for the channel */925	pmz_interrupt_control(uap, 0);926 927	if (!ZS_IS_CONS(uap)) {928		/* Disable receiver and transmitter */929		uap->curregs[R3] &= ~RxENABLE;930		uap->curregs[R5] &= ~TxENABLE;931 932		/* Disable break assertion */933		uap->curregs[R5] &= ~SND_BRK;934		pmz_maybe_update_regs(uap);935	}936 937	uart_port_unlock_irqrestore(port, flags);938 939	/* Release interrupt handler */940	free_irq(uap->port.irq, uap);941 942	uart_port_lock_irqsave(port, &flags);943 944	uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;945 946	if (!ZS_IS_CONS(uap))947		pmz_set_scc_power(uap, 0);	/* Shut the chip down */948 949	uart_port_unlock_irqrestore(port, flags);950}951 952/* Shared by TTY driver and serial console setup.  The port lock is held953 * and local interrupts are disabled.954 */955static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,956			      unsigned int iflag, unsigned long baud)957{958	int brg;959 960	/* Switch to external clocking for IrDA high clock rates. That961	 * code could be re-used for Midi interfaces with different962	 * multipliers963	 */964	if (baud >= 115200 && ZS_IS_IRDA(uap)) {965		uap->curregs[R4] = X1CLK;966		uap->curregs[R11] = RCTRxCP | TCTRxCP;967		uap->curregs[R14] = 0; /* BRG off */968		uap->curregs[R12] = 0;969		uap->curregs[R13] = 0;970		uap->flags |= PMACZILOG_FLAG_IS_EXTCLK;971	} else {972		switch (baud) {973		case ZS_CLOCK/16:	/* 230400 */974			uap->curregs[R4] = X16CLK;975			uap->curregs[R11] = 0;976			uap->curregs[R14] = 0;977			break;978		case ZS_CLOCK/32:	/* 115200 */979			uap->curregs[R4] = X32CLK;980			uap->curregs[R11] = 0;981			uap->curregs[R14] = 0;982			break;983		default:984			uap->curregs[R4] = X16CLK;985			uap->curregs[R11] = TCBR | RCBR;986			brg = BPS_TO_BRG(baud, ZS_CLOCK / 16);987			uap->curregs[R12] = (brg & 255);988			uap->curregs[R13] = ((brg >> 8) & 255);989			uap->curregs[R14] = BRENAB;990		}991		uap->flags &= ~PMACZILOG_FLAG_IS_EXTCLK;992	}993 994	/* Character size, stop bits, and parity. */995	uap->curregs[3] &= ~RxN_MASK;996	uap->curregs[5] &= ~TxN_MASK;997 998	switch (cflag & CSIZE) {999	case CS5:1000		uap->curregs[3] |= Rx5;1001		uap->curregs[5] |= Tx5;1002		uap->parity_mask = 0x1f;1003		break;1004	case CS6:1005		uap->curregs[3] |= Rx6;1006		uap->curregs[5] |= Tx6;1007		uap->parity_mask = 0x3f;1008		break;1009	case CS7:1010		uap->curregs[3] |= Rx7;1011		uap->curregs[5] |= Tx7;1012		uap->parity_mask = 0x7f;1013		break;1014	case CS8:1015	default:1016		uap->curregs[3] |= Rx8;1017		uap->curregs[5] |= Tx8;1018		uap->parity_mask = 0xff;1019		break;1020	}1021	uap->curregs[4] &= ~(SB_MASK);1022	if (cflag & CSTOPB)1023		uap->curregs[4] |= SB2;1024	else1025		uap->curregs[4] |= SB1;1026	if (cflag & PARENB)1027		uap->curregs[4] |= PAR_ENAB;1028	else1029		uap->curregs[4] &= ~PAR_ENAB;1030	if (!(cflag & PARODD))1031		uap->curregs[4] |= PAR_EVEN;1032	else1033		uap->curregs[4] &= ~PAR_EVEN;1034 1035	uap->port.read_status_mask = Rx_OVR;1036	if (iflag & INPCK)1037		uap->port.read_status_mask |= CRC_ERR | PAR_ERR;1038	if (iflag & (IGNBRK | BRKINT | PARMRK))1039		uap->port.read_status_mask |= BRK_ABRT;1040 1041	uap->port.ignore_status_mask = 0;1042	if (iflag & IGNPAR)1043		uap->port.ignore_status_mask |= CRC_ERR | PAR_ERR;1044	if (iflag & IGNBRK) {1045		uap->port.ignore_status_mask |= BRK_ABRT;1046		if (iflag & IGNPAR)1047			uap->port.ignore_status_mask |= Rx_OVR;1048	}1049 1050	if ((cflag & CREAD) == 0)1051		uap->port.ignore_status_mask = 0xff;1052}1053 1054 1055/*1056 * Set the irda codec on the imac to the specified baud rate.1057 */1058static void pmz_irda_setup(struct uart_pmac_port *uap, unsigned long *baud)1059{1060	u8 cmdbyte;1061	int t, version;1062 1063	switch (*baud) {1064	/* SIR modes */1065	case 2400:1066		cmdbyte = 0x53;1067		break;1068	case 4800:1069		cmdbyte = 0x52;1070		break;1071	case 9600:1072		cmdbyte = 0x51;1073		break;1074	case 19200:1075		cmdbyte = 0x50;1076		break;1077	case 38400:1078		cmdbyte = 0x4f;1079		break;1080	case 57600:1081		cmdbyte = 0x4e;1082		break;1083	case 115200:1084		cmdbyte = 0x4d;1085		break;1086	/* The FIR modes aren't really supported at this point, how1087	 * do we select the speed ? via the FCR on KeyLargo ?1088	 */1089	case 1152000:1090		cmdbyte = 0;1091		break;1092	case 4000000:1093		cmdbyte = 0;1094		break;1095	default: /* 9600 */1096		cmdbyte = 0x51;1097		*baud = 9600;1098		break;1099	}1100 1101	/* Wait for transmitter to drain */1102	t = 10000;1103	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 01104	       || (read_zsreg(uap, R1) & ALL_SNT) == 0) {1105		if (--t <= 0) {1106			pmz_error("transmitter didn't drain\n");1107			return;1108		}1109		udelay(10);1110	}1111 1112	/* Drain the receiver too */1113	t = 100;1114	(void)read_zsdata(uap);1115	(void)read_zsdata(uap);1116	(void)read_zsdata(uap);1117	mdelay(10);1118	while (read_zsreg(uap, R0) & Rx_CH_AV) {1119		read_zsdata(uap);1120		mdelay(10);1121		if (--t <= 0) {1122			pmz_error("receiver didn't drain\n");1123			return;1124		}1125	}1126 1127	/* Switch to command mode */1128	uap->curregs[R5] |= DTR;1129	write_zsreg(uap, R5, uap->curregs[R5]);1130	zssync(uap);1131	mdelay(1);1132 1133	/* Switch SCC to 19200 */1134	pmz_convert_to_zs(uap, CS8, 0, 19200);		1135	pmz_load_zsregs(uap, uap->curregs);1136	mdelay(1);1137 1138	/* Write get_version command byte */1139	write_zsdata(uap, 1);1140	t = 5000;1141	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {1142		if (--t <= 0) {1143			pmz_error("irda_setup timed out on get_version byte\n");1144			goto out;1145		}1146		udelay(10);1147	}1148	version = read_zsdata(uap);1149 1150	if (version < 4) {1151		pmz_info("IrDA: dongle version %d not supported\n", version);1152		goto out;1153	}1154 1155	/* Send speed mode */1156	write_zsdata(uap, cmdbyte);1157	t = 5000;1158	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {1159		if (--t <= 0) {1160			pmz_error("irda_setup timed out on speed mode byte\n");1161			goto out;1162		}1163		udelay(10);1164	}1165	t = read_zsdata(uap);1166	if (t != cmdbyte)1167		pmz_error("irda_setup speed mode byte = %x (%x)\n", t, cmdbyte);1168 1169	pmz_info("IrDA setup for %ld bps, dongle version: %d\n",1170		 *baud, version);1171 1172	(void)read_zsdata(uap);1173	(void)read_zsdata(uap);1174	(void)read_zsdata(uap);1175 1176 out:1177	/* Switch back to data mode */1178	uap->curregs[R5] &= ~DTR;1179	write_zsreg(uap, R5, uap->curregs[R5]);1180	zssync(uap);1181 1182	(void)read_zsdata(uap);1183	(void)read_zsdata(uap);1184	(void)read_zsdata(uap);1185}1186 1187 1188static void __pmz_set_termios(struct uart_port *port, struct ktermios *termios,1189			      const struct ktermios *old)1190{1191	struct uart_pmac_port *uap = to_pmz(port);1192	unsigned long baud;1193 1194	/* XXX Check which revs of machines actually allow 1 and 4Mb speeds1195	 * on the IR dongle. Note that the IRTTY driver currently doesn't know1196	 * about the FIR mode and high speed modes. So these are unused. For1197	 * implementing proper support for these, we should probably add some1198	 * DMA as well, at least on the Rx side, which isn't a simple thing1199	 * at this point.1200	 */1201	if (ZS_IS_IRDA(uap)) {1202		/* Calc baud rate */1203		baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);1204		pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);1205		/* Cet the irda codec to the right rate */1206		pmz_irda_setup(uap, &baud);1207		/* Set final baud rate */1208		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);1209		pmz_load_zsregs(uap, uap->curregs);1210		zssync(uap);1211	} else {1212		baud = uart_get_baud_rate(port, termios, old, 1200, 230400);1213		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);1214		/* Make sure modem status interrupts are correctly configured */1215		if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {1216			uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;1217			uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;1218		} else {1219			uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);1220			uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;1221		}1222 1223		/* Load registers to the chip */1224		pmz_maybe_update_regs(uap);1225	}1226	uart_update_timeout(port, termios->c_cflag, baud);1227}1228 1229/* The port lock is not held.  */1230static void pmz_set_termios(struct uart_port *port, struct ktermios *termios,1231			    const struct ktermios *old)1232{1233	struct uart_pmac_port *uap = to_pmz(port);1234	unsigned long flags;1235 1236	uart_port_lock_irqsave(port, &flags);	1237 1238	/* Disable IRQs on the port */1239	pmz_interrupt_control(uap, 0);1240 1241	/* Setup new port configuration */1242	__pmz_set_termios(port, termios, old);1243 1244	/* Re-enable IRQs on the port */1245	if (ZS_IS_OPEN(uap))1246		pmz_interrupt_control(uap, 1);1247 1248	uart_port_unlock_irqrestore(port, flags);1249}1250 1251static const char *pmz_type(struct uart_port *port)1252{1253	struct uart_pmac_port *uap = to_pmz(port);1254 1255	if (ZS_IS_IRDA(uap))1256		return "Z85c30 ESCC - Infrared port";1257	else if (ZS_IS_INTMODEM(uap))1258		return "Z85c30 ESCC - Internal modem";1259	return "Z85c30 ESCC - Serial port";1260}1261 1262/* We do not request/release mappings of the registers here, this1263 * happens at early serial probe time.1264 */1265static void pmz_release_port(struct uart_port *port)1266{1267}1268 1269static int pmz_request_port(struct uart_port *port)1270{1271	return 0;1272}1273 1274/* These do not need to do anything interesting either.  */1275static void pmz_config_port(struct uart_port *port, int flags)1276{1277}1278 1279/* We do not support letting the user mess with the divisor, IRQ, etc. */1280static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)1281{1282	return -EINVAL;1283}1284 1285#ifdef CONFIG_CONSOLE_POLL1286 1287static int pmz_poll_get_char(struct uart_port *port)1288{1289	struct uart_pmac_port *uap =1290		container_of(port, struct uart_pmac_port, port);1291	int tries = 2;1292 1293	while (tries) {1294		if ((read_zsreg(uap, R0) & Rx_CH_AV) != 0)1295			return read_zsdata(uap);1296		if (tries--)1297			udelay(5);1298	}1299 1300	return NO_POLL_CHAR;1301}1302 1303static void pmz_poll_put_char(struct uart_port *port, unsigned char c)1304{1305	struct uart_pmac_port *uap =1306		container_of(port, struct uart_pmac_port, port);1307 1308	/* Wait for the transmit buffer to empty. */1309	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)1310		udelay(5);1311	write_zsdata(uap, c);1312}1313 1314#endif /* CONFIG_CONSOLE_POLL */1315 1316static const struct uart_ops pmz_pops = {1317	.tx_empty	=	pmz_tx_empty,1318	.set_mctrl	=	pmz_set_mctrl,1319	.get_mctrl	=	pmz_get_mctrl,1320	.stop_tx	=	pmz_stop_tx,1321	.start_tx	=	pmz_start_tx,1322	.stop_rx	=	pmz_stop_rx,1323	.enable_ms	=	pmz_enable_ms,1324	.break_ctl	=	pmz_break_ctl,1325	.startup	=	pmz_startup,1326	.shutdown	=	pmz_shutdown,1327	.set_termios	=	pmz_set_termios,1328	.type		=	pmz_type,1329	.release_port	=	pmz_release_port,1330	.request_port	=	pmz_request_port,1331	.config_port	=	pmz_config_port,1332	.verify_port	=	pmz_verify_port,1333#ifdef CONFIG_CONSOLE_POLL1334	.poll_get_char	=	pmz_poll_get_char,1335	.poll_put_char	=	pmz_poll_put_char,1336#endif1337};1338 1339#ifdef CONFIG_PPC_PMAC1340 1341/*1342 * Setup one port structure after probing, HW is down at this point,1343 * Unlike sunzilog, we don't need to pre-init the spinlock as we don't1344 * register our console before uart_add_one_port() is called1345 */1346static int __init pmz_init_port(struct uart_pmac_port *uap)1347{1348	struct device_node *np = uap->node;1349	const char *conn;1350	const struct slot_names_prop {1351		int	count;1352		char	name[1];1353	} *slots;1354	int len;1355	struct resource r_ports;1356 1357	/*1358	 * Request & map chip registers1359	 */1360	if (of_address_to_resource(np, 0, &r_ports))1361		return -ENODEV;1362	uap->port.mapbase = r_ports.start;1363	uap->port.membase = ioremap(uap->port.mapbase, 0x1000);1364 1365	uap->control_reg = uap->port.membase;1366	uap->data_reg = uap->control_reg + 0x10;1367 1368	/*1369	 * Detect port type1370	 */1371	if (of_device_is_compatible(np, "cobalt"))1372		uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;1373	conn = of_get_property(np, "AAPL,connector", &len);1374	if (conn && (strcmp(conn, "infrared") == 0))1375		uap->flags |= PMACZILOG_FLAG_IS_IRDA;1376	uap->port_type = PMAC_SCC_ASYNC;1377	/* 1999 Powerbook G3 has slot-names property instead */1378	slots = of_get_property(np, "slot-names", &len);1379	if (slots && slots->count > 0) {1380		if (strcmp(slots->name, "IrDA") == 0)1381			uap->flags |= PMACZILOG_FLAG_IS_IRDA;1382		else if (strcmp(slots->name, "Modem") == 0)1383			uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;1384	}1385	if (ZS_IS_IRDA(uap))1386		uap->port_type = PMAC_SCC_IRDA;1387	if (ZS_IS_INTMODEM(uap)) {1388		struct device_node* i2c_modem =1389			of_find_node_by_name(NULL, "i2c-modem");1390		if (i2c_modem) {1391			const char* mid =1392				of_get_property(i2c_modem, "modem-id", NULL);1393			if (mid) switch(*mid) {1394			case 0x04 :1395			case 0x05 :1396			case 0x07 :1397			case 0x08 :1398			case 0x0b :1399			case 0x0c :1400				uap->port_type = PMAC_SCC_I2S1;1401			}1402			printk(KERN_INFO "pmac_zilog: i2c-modem detected, id: %d\n",1403				mid ? (*mid) : 0);1404			of_node_put(i2c_modem);1405		} else {1406			printk(KERN_INFO "pmac_zilog: serial modem detected\n");1407		}1408	}1409 1410	/*1411	 * Init remaining bits of "port" structure1412	 */1413	uap->port.iotype = UPIO_MEM;1414	uap->port.irq = irq_of_parse_and_map(np, 0);1415	uap->port.uartclk = ZS_CLOCK;1416	uap->port.fifosize = 1;1417	uap->port.ops = &pmz_pops;1418	uap->port.type = PORT_PMAC_ZILOG;1419	uap->port.flags = 0;1420 1421	/*1422	 * Fixup for the port on Gatwick for which the device-tree has1423	 * missing interrupts. Normally, the macio_dev would contain1424	 * fixed up interrupt info, but we use the device-tree directly1425	 * here due to early probing so we need the fixup too.1426	 */1427	if (uap->port.irq == 0 &&1428	    np->parent && np->parent->parent &&1429	    of_device_is_compatible(np->parent->parent, "gatwick")) {1430		/* IRQs on gatwick are offset by 64 */1431		uap->port.irq = irq_create_mapping(NULL, 64 + 15);1432	}1433 1434	/* Setup some valid baud rate information in the register1435	 * shadows so we don't write crap there before baud rate is1436	 * first initialized.1437	 */1438	pmz_convert_to_zs(uap, CS8, 0, 9600);1439 1440	return 0;1441}1442 1443/*1444 * Get rid of a port on module removal1445 */1446static void pmz_dispose_port(struct uart_pmac_port *uap)1447{1448	struct device_node *np;1449 1450	np = uap->node;1451	iounmap(uap->control_reg);1452	uap->node = NULL;1453	of_node_put(np);1454	memset(uap, 0, sizeof(struct uart_pmac_port));1455}1456 1457/*1458 * Called upon match with an escc node in the device-tree.1459 */1460static int pmz_attach(struct macio_dev *mdev, const struct of_device_id *match)1461{1462	struct uart_pmac_port *uap;1463	int i;1464	1465	/* Iterate the pmz_ports array to find a matching entry1466	 */1467	for (i = 0; i < MAX_ZS_PORTS; i++)1468		if (pmz_ports[i].node == mdev->ofdev.dev.of_node)1469			break;1470	if (i >= MAX_ZS_PORTS)1471		return -ENODEV;1472 1473 1474	uap = &pmz_ports[i];1475	uap->dev = mdev;1476	uap->port.dev = &mdev->ofdev.dev;1477	dev_set_drvdata(&mdev->ofdev.dev, uap);1478 1479	/* We still activate the port even when failing to request resources1480	 * to work around bugs in ancient Apple device-trees1481	 */1482	if (macio_request_resources(uap->dev, "pmac_zilog"))1483		printk(KERN_WARNING "%pOFn: Failed to request resource"1484		       ", port still active\n",1485		       uap->node);1486	else1487		uap->flags |= PMACZILOG_FLAG_RSRC_REQUESTED;1488 1489	return uart_add_one_port(&pmz_uart_reg, &uap->port);1490}1491 1492/*1493 * That one should not be called, macio isn't really a hotswap device,1494 * we don't expect one of those serial ports to go away...1495 */1496static void pmz_detach(struct macio_dev *mdev)1497{1498	struct uart_pmac_port	*uap = dev_get_drvdata(&mdev->ofdev.dev);1499	1500	if (!uap)1501		return;1502 1503	uart_remove_one_port(&pmz_uart_reg, &uap->port);1504 1505	if (uap->flags & PMACZILOG_FLAG_RSRC_REQUESTED) {1506		macio_release_resources(uap->dev);1507		uap->flags &= ~PMACZILOG_FLAG_RSRC_REQUESTED;1508	}1509	dev_set_drvdata(&mdev->ofdev.dev, NULL);1510	uap->dev = NULL;1511	uap->port.dev = NULL;1512}1513 1514static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)1515{1516	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);1517 1518	if (uap == NULL) {1519		printk("HRM... pmz_suspend with NULL uap\n");1520		return 0;1521	}1522 1523	uart_suspend_port(&pmz_uart_reg, &uap->port);1524 1525	return 0;1526}1527 1528 1529static int pmz_resume(struct macio_dev *mdev)1530{1531	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);1532 1533	if (uap == NULL)1534		return 0;1535 1536	uart_resume_port(&pmz_uart_reg, &uap->port);1537 1538	return 0;1539}1540 1541/*1542 * Probe all ports in the system and build the ports array, we register1543 * with the serial layer later, so we get a proper struct device which1544 * allows the tty to attach properly. This is later than it used to be1545 * but the tty layer really wants it that way.1546 */1547static int __init pmz_probe(void)1548{1549	struct device_node	*node_p, *node_a, *node_b, *np;1550	int			count = 0;1551	int			rc;1552 1553	/*1554	 * Find all escc chips in the system1555	 */1556	for_each_node_by_name(node_p, "escc") {1557		/*1558		 * First get channel A/B node pointers1559		 * 1560		 * TODO: Add routines with proper locking to do that...1561		 */1562		node_a = node_b = NULL;1563		for_each_child_of_node(node_p, np) {1564			if (of_node_name_prefix(np, "ch-a"))1565				node_a = of_node_get(np);1566			else if (of_node_name_prefix(np, "ch-b"))1567				node_b = of_node_get(np);1568		}1569		if (!node_a && !node_b) {1570			of_node_put(node_a);1571			of_node_put(node_b);1572			printk(KERN_ERR "pmac_zilog: missing node %c for escc %pOF\n",1573				(!node_a) ? 'a' : 'b', node_p);1574			continue;1575		}1576 1577		/*1578		 * Fill basic fields in the port structures1579		 */1580		if (node_b != NULL) {1581			pmz_ports[count].mate		= &pmz_ports[count+1];1582			pmz_ports[count+1].mate		= &pmz_ports[count];1583		}1584		pmz_ports[count].flags		= PMACZILOG_FLAG_IS_CHANNEL_A;1585		pmz_ports[count].node		= node_a;1586		pmz_ports[count+1].node		= node_b;1587		pmz_ports[count].port.line	= count;1588		pmz_ports[count+1].port.line	= count+1;1589 1590		/*1591		 * Setup the ports for real1592		 */1593		rc = pmz_init_port(&pmz_ports[count]);1594		if (rc == 0 && node_b != NULL)1595			rc = pmz_init_port(&pmz_ports[count+1]);1596		if (rc != 0) {1597			of_node_put(node_a);1598			of_node_put(node_b);1599			memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));1600			memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));1601			continue;1602		}1603		count += 2;1604	}1605	pmz_ports_count = count;1606 1607	return 0;1608}1609 1610#else1611 1612/* On PCI PowerMacs, pmz_probe() does an explicit search of the OpenFirmware1613 * tree to obtain the device_nodes needed to start the console before the1614 * macio driver. On Macs without OpenFirmware, global platform_devices take1615 * the place of those device_nodes.1616 */1617extern struct platform_device scc_a_pdev, scc_b_pdev;1618 1619static int __init pmz_init_port(struct uart_pmac_port *uap)1620{1621	struct resource *r_ports;1622	int irq;1623 1624	r_ports = platform_get_resource(uap->pdev, IORESOURCE_MEM, 0);1625	if (!r_ports)1626		return -ENODEV;1627 1628	irq = platform_get_irq(uap->pdev, 0);1629	if (irq < 0)1630		return irq;1631 1632	uap->port.mapbase  = r_ports->start;1633	uap->port.membase  = (unsigned char __iomem *) r_ports->start;1634	uap->port.iotype   = UPIO_MEM;1635	uap->port.irq      = irq;1636	uap->port.uartclk  = ZS_CLOCK;1637	uap->port.fifosize = 1;1638	uap->port.ops      = &pmz_pops;1639	uap->port.type     = PORT_PMAC_ZILOG;1640	uap->port.flags    = 0;1641 1642	uap->control_reg   = uap->port.membase;1643	uap->data_reg      = uap->control_reg + 4;1644	uap->port_type     = 0;1645	uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_PMACZILOG_CONSOLE);1646 1647	pmz_convert_to_zs(uap, CS8, 0, 9600);1648 1649	return 0;1650}1651 1652static int __init pmz_probe(void)1653{1654	int err;1655 1656	pmz_ports_count = 0;1657 1658	pmz_ports[0].port.line = 0;1659	pmz_ports[0].flags     = PMACZILOG_FLAG_IS_CHANNEL_A;1660	pmz_ports[0].pdev      = &scc_a_pdev;1661	err = pmz_init_port(&pmz_ports[0]);1662	if (err)1663		return err;1664	pmz_ports_count++;1665 1666	pmz_ports[0].mate      = &pmz_ports[1];1667	pmz_ports[1].mate      = &pmz_ports[0];1668	pmz_ports[1].port.line = 1;1669	pmz_ports[1].flags     = 0;1670	pmz_ports[1].pdev      = &scc_b_pdev;1671	err = pmz_init_port(&pmz_ports[1]);1672	if (err)1673		return err;1674	pmz_ports_count++;1675 1676	return 0;1677}1678 1679static void pmz_dispose_port(struct uart_pmac_port *uap)1680{1681	memset(uap, 0, sizeof(struct uart_pmac_port));1682}1683 1684static int pmz_attach(struct platform_device *pdev)1685{1686	struct uart_pmac_port *uap;1687	int i;1688 1689	/* Iterate the pmz_ports array to find a matching entry */1690	for (i = 0; i < pmz_ports_count; i++)1691		if (pmz_ports[i].pdev == pdev)1692			break;1693	if (i >= pmz_ports_count)1694		return -ENODEV;1695 1696	uap = &pmz_ports[i];1697	uap->port.dev = &pdev->dev;1698	platform_set_drvdata(pdev, uap);1699 1700	return uart_add_one_port(&pmz_uart_reg, &uap->port);1701}1702 1703static void pmz_detach(struct platform_device *pdev)1704{1705	struct uart_pmac_port *uap = platform_get_drvdata(pdev);1706 1707	uart_remove_one_port(&pmz_uart_reg, &uap->port);1708 1709	uap->port.dev = NULL;1710}1711 1712#endif /* !CONFIG_PPC_PMAC */1713 1714#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE1715 1716static void pmz_console_write(struct console *con, const char *s, unsigned int count);1717static int __init pmz_console_setup(struct console *co, char *options);1718 1719static struct console pmz_console = {1720	.name	=	PMACZILOG_NAME,1721	.write	=	pmz_console_write,1722	.device	=	uart_console_device,1723	.setup	=	pmz_console_setup,1724	.flags	=	CON_PRINTBUFFER,1725	.index	=	-1,1726	.data   =	&pmz_uart_reg,1727};1728 1729#define PMACZILOG_CONSOLE	&pmz_console1730#else /* CONFIG_SERIAL_PMACZILOG_CONSOLE */1731#define PMACZILOG_CONSOLE	(NULL)1732#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */1733 1734/*1735 * Register the driver, console driver and ports with the serial1736 * core1737 */1738static int __init pmz_register(void)1739{1740	pmz_uart_reg.nr = pmz_ports_count;1741	pmz_uart_reg.cons = PMACZILOG_CONSOLE;1742 1743	/*1744	 * Register this driver with the serial core1745	 */1746	return uart_register_driver(&pmz_uart_reg);1747}1748 1749#ifdef CONFIG_PPC_PMAC1750 1751static const struct of_device_id pmz_match[] =1752{1753	{1754	.name		= "ch-a",1755	},1756	{1757	.name		= "ch-b",1758	},1759	{},1760};1761MODULE_DEVICE_TABLE (of, pmz_match);1762 1763static struct macio_driver pmz_driver = {1764	.driver = {1765		.name 		= "pmac_zilog",1766		.owner		= THIS_MODULE,1767		.of_match_table	= pmz_match,1768	},1769	.probe		= pmz_attach,1770	.remove		= pmz_detach,1771	.suspend	= pmz_suspend,1772	.resume		= pmz_resume,1773};1774 1775#else1776 1777static struct platform_driver pmz_driver = {1778	.probe		= pmz_attach,1779	.remove_new	= pmz_detach,1780	.driver		= {1781		.name		= "scc",1782	},1783};1784 1785#endif /* !CONFIG_PPC_PMAC */1786 1787static int __init init_pmz(void)1788{1789	int rc, i;1790 1791	/* 1792	 * First, we need to do a direct OF-based probe pass. We1793	 * do that because we want serial console up before the1794	 * macio stuffs calls us back, and since that makes it1795	 * easier to pass the proper number of channels to1796	 * uart_register_driver()1797	 */1798	if (pmz_ports_count == 0)1799		pmz_probe();1800 1801	/*1802	 * Bail early if no port found1803	 */1804	if (pmz_ports_count == 0)1805		return -ENODEV;1806 1807	/*1808	 * Now we register with the serial layer1809	 */1810	rc = pmz_register();1811	if (rc) {1812		printk(KERN_ERR 1813			"pmac_zilog: Error registering serial device, disabling pmac_zilog.\n"1814		 	"pmac_zilog: Did another serial driver already claim the minors?\n"); 1815		/* effectively "pmz_unprobe()" */1816		for (i=0; i < pmz_ports_count; i++)1817			pmz_dispose_port(&pmz_ports[i]);1818		return rc;1819	}1820 1821	/*1822	 * Then we register the macio driver itself1823	 */1824#ifdef CONFIG_PPC_PMAC1825	return macio_register_driver(&pmz_driver);1826#else1827	return platform_driver_register(&pmz_driver);1828#endif1829}1830 1831static void __exit exit_pmz(void)1832{1833	int i;1834 1835#ifdef CONFIG_PPC_PMAC1836	/* Get rid of macio-driver (detach from macio) */1837	macio_unregister_driver(&pmz_driver);1838#else1839	platform_driver_unregister(&pmz_driver);1840#endif1841 1842	for (i = 0; i < pmz_ports_count; i++) {1843		struct uart_pmac_port *uport = &pmz_ports[i];1844#ifdef CONFIG_PPC_PMAC1845		if (uport->node != NULL)1846			pmz_dispose_port(uport);1847#else1848		if (uport->pdev != NULL)1849			pmz_dispose_port(uport);1850#endif1851	}1852	/* Unregister UART driver */1853	uart_unregister_driver(&pmz_uart_reg);1854}1855 1856#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE1857 1858static void pmz_console_putchar(struct uart_port *port, unsigned char ch)1859{1860	struct uart_pmac_port *uap =1861		container_of(port, struct uart_pmac_port, port);1862 1863	/* Wait for the transmit buffer to empty. */1864	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)1865		udelay(5);1866	write_zsdata(uap, ch);1867}1868 1869/*1870 * Print a string to the serial port trying not to disturb1871 * any possible real use of the port...1872 */1873static void pmz_console_write(struct console *con, const char *s, unsigned int count)1874{1875	struct uart_pmac_port *uap = &pmz_ports[con->index];1876	unsigned long flags;1877 1878	uart_port_lock_irqsave(&uap->port, &flags);1879 1880	/* Turn of interrupts and enable the transmitter. */1881	write_zsreg(uap, R1, uap->curregs[1] & ~TxINT_ENAB);1882	write_zsreg(uap, R5, uap->curregs[5] | TxENABLE | RTS | DTR);1883 1884	uart_console_write(&uap->port, s, count, pmz_console_putchar);1885 1886	/* Restore the values in the registers. */1887	write_zsreg(uap, R1, uap->curregs[1]);1888	/* Don't disable the transmitter. */1889 1890	uart_port_unlock_irqrestore(&uap->port, flags);1891}1892 1893/*1894 * Setup the serial console1895 */1896static int __init pmz_console_setup(struct console *co, char *options)1897{1898	struct uart_pmac_port *uap;1899	struct uart_port *port;1900	int baud = 38400;1901	int bits = 8;1902	int parity = 'n';1903	int flow = 'n';1904	unsigned long pwr_delay;1905 1906	/*1907	 * XServe's default to 57600 bps1908	 */1909	if (of_machine_is_compatible("RackMac1,1")1910	    || of_machine_is_compatible("RackMac1,2")1911	    || of_machine_is_compatible("MacRISC4"))1912		baud = 57600;1913 1914	/*1915	 * Check whether an invalid uart number has been specified, and1916	 * if so, search for the first available port that does have1917	 * console support.1918	 */1919	if (co->index >= pmz_ports_count)1920		co->index = 0;1921	uap = &pmz_ports[co->index];1922#ifdef CONFIG_PPC_PMAC1923	if (uap->node == NULL)1924		return -ENODEV;1925#else1926	if (uap->pdev == NULL)1927		return -ENODEV;1928#endif1929	port = &uap->port;1930 1931	/*1932	 * Mark port as beeing a console1933	 */1934	uap->flags |= PMACZILOG_FLAG_IS_CONS;1935 1936	/*1937	 * Temporary fix for uart layer who didn't setup the spinlock yet1938	 */1939	spin_lock_init(&port->lock);1940 1941	/*1942	 * Enable the hardware1943	 */1944	pwr_delay = __pmz_startup(uap);1945	if (pwr_delay)1946		mdelay(pwr_delay);1947	1948	if (options)1949		uart_parse_options(options, &baud, &parity, &bits, &flow);1950 1951	return uart_set_options(port, co, baud, parity, bits, flow);1952}1953 1954static int __init pmz_console_init(void)1955{1956	/* Probe ports */1957	pmz_probe();1958 1959	if (pmz_ports_count == 0)1960		return -ENODEV;1961 1962	/* TODO: Autoprobe console based on OF */1963	/* pmz_console.index = i; */1964	register_console(&pmz_console);1965 1966	return 0;1967 1968}1969console_initcall(pmz_console_init);1970#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */1971 1972module_init(init_pmz);1973module_exit(exit_pmz);1974