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v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/* sunsab.c: ASYNC Driver for the SIEMENS SAB82532 DUSCC.
   3 *
   4 * Copyright (C) 1997  Eddie C. Dost  (ecd@skynet.be)
   5 * Copyright (C) 2002, 2006  David S. Miller (davem@davemloft.net)
   6 *
   7 * Rewrote buffer handling to use CIRC(Circular Buffer) macros.
   8 *   Maxim Krasnyanskiy <maxk@qualcomm.com>
   9 *
  10 * Fixed to use tty_get_baud_rate, and to allow for arbitrary baud
  11 * rates to be programmed into the UART.  Also eliminated a lot of
  12 * duplicated code in the console setup.
  13 *   Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12
  14 *
  15 * Ported to new 2.5.x UART layer.
  16 *   David S. Miller <davem@davemloft.net>
  17 */
  18
  19#include <linux/module.h>
  20#include <linux/kernel.h>
  21#include <linux/errno.h>
  22#include <linux/tty.h>
  23#include <linux/tty_flip.h>
  24#include <linux/major.h>
  25#include <linux/string.h>
  26#include <linux/ptrace.h>
  27#include <linux/ioport.h>
  28#include <linux/circ_buf.h>
  29#include <linux/serial.h>
  30#include <linux/sysrq.h>
  31#include <linux/console.h>
  32#include <linux/spinlock.h>
  33#include <linux/slab.h>
  34#include <linux/delay.h>
  35#include <linux/init.h>
  36#include <linux/of_device.h>
  37
  38#include <asm/io.h>
  39#include <asm/irq.h>
  40#include <asm/prom.h>
  41#include <asm/setup.h>
  42
  43#if defined(CONFIG_SERIAL_SUNSAB_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  44#define SUPPORT_SYSRQ
  45#endif
  46
  47#include <linux/serial_core.h>
  48#include <linux/sunserialcore.h>
  49
  50#include "sunsab.h"
  51
  52struct uart_sunsab_port {
  53	struct uart_port		port;		/* Generic UART port	*/
  54	union sab82532_async_regs	__iomem *regs;	/* Chip registers	*/
  55	unsigned long			irqflags;	/* IRQ state flags	*/
  56	int				dsr;		/* Current DSR state	*/
  57	unsigned int			cec_timeout;	/* Chip poll timeout... */
  58	unsigned int			tec_timeout;	/* likewise		*/
  59	unsigned char			interrupt_mask0;/* ISR0 masking		*/
  60	unsigned char			interrupt_mask1;/* ISR1 masking		*/
  61	unsigned char			pvr_dtr_bit;	/* Which PVR bit is DTR */
  62	unsigned char			pvr_dsr_bit;	/* Which PVR bit is DSR */
  63	unsigned int			gis_shift;
  64	int				type;		/* SAB82532 version	*/
  65
  66	/* Setting configuration bits while the transmitter is active
  67	 * can cause garbage characters to get emitted by the chip.
  68	 * Therefore, we cache such writes here and do the real register
  69	 * write the next time the transmitter becomes idle.
  70	 */
  71	unsigned int			cached_ebrg;
  72	unsigned char			cached_mode;
  73	unsigned char			cached_pvr;
  74	unsigned char			cached_dafo;
  75};
  76
  77/*
  78 * This assumes you have a 29.4912 MHz clock for your UART.
  79 */
  80#define SAB_BASE_BAUD ( 29491200 / 16 )
  81
  82static char *sab82532_version[16] = {
  83	"V1.0", "V2.0", "V3.2", "V(0x03)",
  84	"V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)",
  85	"V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)",
  86	"V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)"
  87};
  88
  89#define SAB82532_MAX_TEC_TIMEOUT 200000	/* 1 character time (at 50 baud) */
  90#define SAB82532_MAX_CEC_TIMEOUT  50000	/* 2.5 TX CLKs (at 50 baud) */
  91
  92#define SAB82532_RECV_FIFO_SIZE	32      /* Standard async fifo sizes */
  93#define SAB82532_XMIT_FIFO_SIZE	32
  94
  95static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up)
  96{
  97	int timeout = up->tec_timeout;
  98
  99	while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout)
 100		udelay(1);
 101}
 102
 103static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
 104{
 105	int timeout = up->cec_timeout;
 106
 107	while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout)
 108		udelay(1);
 109}
 110
 111static struct tty_port *
 112receive_chars(struct uart_sunsab_port *up,
 113	      union sab82532_irq_status *stat)
 114{
 115	struct tty_port *port = NULL;
 116	unsigned char buf[32];
 117	int saw_console_brk = 0;
 118	int free_fifo = 0;
 119	int count = 0;
 120	int i;
 121
 122	if (up->port.state != NULL)		/* Unopened serial console */
 123		port = &up->port.state->port;
 124
 125	/* Read number of BYTES (Character + Status) available. */
 126	if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
 127		count = SAB82532_RECV_FIFO_SIZE;
 128		free_fifo++;
 129	}
 130
 131	if (stat->sreg.isr0 & SAB82532_ISR0_TCD) {
 132		count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1);
 133		free_fifo++;
 134	}
 135
 136	/* Issue a FIFO read command in case we where idle. */
 137	if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
 138		sunsab_cec_wait(up);
 139		writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
 140		return port;
 141	}
 142
 143	if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 144		free_fifo++;
 145
 146	/* Read the FIFO. */
 147	for (i = 0; i < count; i++)
 148		buf[i] = readb(&up->regs->r.rfifo[i]);
 149
 150	/* Issue Receive Message Complete command. */
 151	if (free_fifo) {
 152		sunsab_cec_wait(up);
 153		writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr);
 154	}
 155
 156	/* Count may be zero for BRK, so we check for it here */
 157	if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) &&
 158	    (up->port.line == up->port.cons->index))
 159		saw_console_brk = 1;
 160
 161	if (count == 0) {
 162		if (unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 163			stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 164					     SAB82532_ISR0_FERR);
 165			up->port.icount.brk++;
 166			uart_handle_break(&up->port);
 167		}
 168	}
 169
 170	for (i = 0; i < count; i++) {
 171		unsigned char ch = buf[i], flag;
 172
 173		flag = TTY_NORMAL;
 174		up->port.icount.rx++;
 175
 176		if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
 177						SAB82532_ISR0_FERR |
 178						SAB82532_ISR0_RFO)) ||
 179		    unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 180			/*
 181			 * For statistics only
 182			 */
 183			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 184				stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 185						     SAB82532_ISR0_FERR);
 186				up->port.icount.brk++;
 187				/*
 188				 * We do the SysRQ and SAK checking
 189				 * here because otherwise the break
 190				 * may get masked by ignore_status_mask
 191				 * or read_status_mask.
 192				 */
 193				if (uart_handle_break(&up->port))
 194					continue;
 195			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 196				up->port.icount.parity++;
 197			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 198				up->port.icount.frame++;
 199			if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 200				up->port.icount.overrun++;
 201
 202			/*
 203			 * Mask off conditions which should be ingored.
 204			 */
 205			stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
 206			stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
 207
 208			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 209				flag = TTY_BREAK;
 210			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 211				flag = TTY_PARITY;
 212			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 213				flag = TTY_FRAME;
 214		}
 215
 216		if (uart_handle_sysrq_char(&up->port, ch) || !port)
 217			continue;
 218
 219		if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
 220		    (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
 221			tty_insert_flip_char(port, ch, flag);
 222		if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 223			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 224	}
 225
 226	if (saw_console_brk)
 227		sun_do_break();
 228
 229	return port;
 230}
 231
 232static void sunsab_stop_tx(struct uart_port *);
 233static void sunsab_tx_idle(struct uart_sunsab_port *);
 234
 235static void transmit_chars(struct uart_sunsab_port *up,
 236			   union sab82532_irq_status *stat)
 237{
 238	struct circ_buf *xmit = &up->port.state->xmit;
 239	int i;
 240
 241	if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
 242		up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
 243		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 244		set_bit(SAB82532_ALLS, &up->irqflags);
 245	}
 246
 247#if 0 /* bde@nwlink.com says this check causes problems */
 248	if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
 249		return;
 250#endif
 251
 252	if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
 253		return;
 254
 255	set_bit(SAB82532_XPR, &up->irqflags);
 256	sunsab_tx_idle(up);
 257
 258	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 259		up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 260		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 261		return;
 262	}
 263
 264	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 265	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 266	clear_bit(SAB82532_ALLS, &up->irqflags);
 267
 268	/* Stuff 32 bytes into Transmit FIFO. */
 269	clear_bit(SAB82532_XPR, &up->irqflags);
 270	for (i = 0; i < up->port.fifosize; i++) {
 271		writeb(xmit->buf[xmit->tail],
 272		       &up->regs->w.xfifo[i]);
 273		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 274		up->port.icount.tx++;
 275		if (uart_circ_empty(xmit))
 276			break;
 277	}
 278
 279	/* Issue a Transmit Frame command. */
 280	sunsab_cec_wait(up);
 281	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 282
 283	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 284		uart_write_wakeup(&up->port);
 285
 286	if (uart_circ_empty(xmit))
 287		sunsab_stop_tx(&up->port);
 288}
 289
 290static void check_status(struct uart_sunsab_port *up,
 291			 union sab82532_irq_status *stat)
 292{
 293	if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
 294		uart_handle_dcd_change(&up->port,
 295				       !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
 296
 297	if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
 298		uart_handle_cts_change(&up->port,
 299				       (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
 300
 301	if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
 302		up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
 303		up->port.icount.dsr++;
 304	}
 305
 306	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 307}
 308
 309static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
 310{
 311	struct uart_sunsab_port *up = dev_id;
 312	struct tty_port *port = NULL;
 313	union sab82532_irq_status status;
 314	unsigned long flags;
 315	unsigned char gis;
 316
 317	spin_lock_irqsave(&up->port.lock, flags);
 318
 319	status.stat = 0;
 320	gis = readb(&up->regs->r.gis) >> up->gis_shift;
 321	if (gis & 1)
 322		status.sreg.isr0 = readb(&up->regs->r.isr0);
 323	if (gis & 2)
 324		status.sreg.isr1 = readb(&up->regs->r.isr1);
 325
 326	if (status.stat) {
 327		if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 328					 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
 329		    (status.sreg.isr1 & SAB82532_ISR1_BRK))
 330			port = receive_chars(up, &status);
 331		if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
 332		    (status.sreg.isr1 & SAB82532_ISR1_CSC))
 333			check_status(up, &status);
 334		if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
 335			transmit_chars(up, &status);
 336	}
 337
 338	spin_unlock_irqrestore(&up->port.lock, flags);
 339
 340	if (port)
 341		tty_flip_buffer_push(port);
 342
 343	return IRQ_HANDLED;
 344}
 345
 346/* port->lock is not held.  */
 347static unsigned int sunsab_tx_empty(struct uart_port *port)
 348{
 349	struct uart_sunsab_port *up =
 350		container_of(port, struct uart_sunsab_port, port);
 351	int ret;
 352
 353	/* Do not need a lock for a state test like this.  */
 354	if (test_bit(SAB82532_ALLS, &up->irqflags))
 355		ret = TIOCSER_TEMT;
 356	else
 357		ret = 0;
 358
 359	return ret;
 360}
 361
 362/* port->lock held by caller.  */
 363static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
 364{
 365	struct uart_sunsab_port *up =
 366		container_of(port, struct uart_sunsab_port, port);
 367
 368	if (mctrl & TIOCM_RTS) {
 369		up->cached_mode &= ~SAB82532_MODE_FRTS;
 370		up->cached_mode |= SAB82532_MODE_RTS;
 371	} else {
 372		up->cached_mode |= (SAB82532_MODE_FRTS |
 373				    SAB82532_MODE_RTS);
 374	}
 375	if (mctrl & TIOCM_DTR) {
 376		up->cached_pvr &= ~(up->pvr_dtr_bit);
 377	} else {
 378		up->cached_pvr |= up->pvr_dtr_bit;
 379	}
 380
 381	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 382	if (test_bit(SAB82532_XPR, &up->irqflags))
 383		sunsab_tx_idle(up);
 384}
 385
 386/* port->lock is held by caller and interrupts are disabled.  */
 387static unsigned int sunsab_get_mctrl(struct uart_port *port)
 388{
 389	struct uart_sunsab_port *up =
 390		container_of(port, struct uart_sunsab_port, port);
 391	unsigned char val;
 392	unsigned int result;
 393
 394	result = 0;
 395
 396	val = readb(&up->regs->r.pvr);
 397	result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
 398
 399	val = readb(&up->regs->r.vstr);
 400	result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
 401
 402	val = readb(&up->regs->r.star);
 403	result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
 404
 405	return result;
 406}
 407
 408/* port->lock held by caller.  */
 409static void sunsab_stop_tx(struct uart_port *port)
 410{
 411	struct uart_sunsab_port *up =
 412		container_of(port, struct uart_sunsab_port, port);
 413
 414	up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 415	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 416}
 417
 418/* port->lock held by caller.  */
 419static void sunsab_tx_idle(struct uart_sunsab_port *up)
 420{
 421	if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
 422		u8 tmp;
 423
 424		clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
 425		writeb(up->cached_mode, &up->regs->rw.mode);
 426		writeb(up->cached_pvr, &up->regs->rw.pvr);
 427		writeb(up->cached_dafo, &up->regs->w.dafo);
 428
 429		writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
 430		tmp = readb(&up->regs->rw.ccr2);
 431		tmp &= ~0xc0;
 432		tmp |= (up->cached_ebrg >> 2) & 0xc0;
 433		writeb(tmp, &up->regs->rw.ccr2);
 434	}
 435}
 436
 437/* port->lock held by caller.  */
 438static void sunsab_start_tx(struct uart_port *port)
 439{
 440	struct uart_sunsab_port *up =
 441		container_of(port, struct uart_sunsab_port, port);
 442	struct circ_buf *xmit = &up->port.state->xmit;
 443	int i;
 444
 445	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
 446		return;
 447
 448	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 449	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 450	
 451	if (!test_bit(SAB82532_XPR, &up->irqflags))
 452		return;
 453
 454	clear_bit(SAB82532_ALLS, &up->irqflags);
 455	clear_bit(SAB82532_XPR, &up->irqflags);
 456
 457	for (i = 0; i < up->port.fifosize; i++) {
 458		writeb(xmit->buf[xmit->tail],
 459		       &up->regs->w.xfifo[i]);
 460		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 461		up->port.icount.tx++;
 462		if (uart_circ_empty(xmit))
 463			break;
 464	}
 465
 466	/* Issue a Transmit Frame command.  */
 467	sunsab_cec_wait(up);
 468	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 469}
 470
 471/* port->lock is not held.  */
 472static void sunsab_send_xchar(struct uart_port *port, char ch)
 473{
 474	struct uart_sunsab_port *up =
 475		container_of(port, struct uart_sunsab_port, port);
 476	unsigned long flags;
 477
 478	if (ch == __DISABLED_CHAR)
 479		return;
 480
 481	spin_lock_irqsave(&up->port.lock, flags);
 482
 483	sunsab_tec_wait(up);
 484	writeb(ch, &up->regs->w.tic);
 485
 486	spin_unlock_irqrestore(&up->port.lock, flags);
 487}
 488
 489/* port->lock held by caller.  */
 490static void sunsab_stop_rx(struct uart_port *port)
 491{
 492	struct uart_sunsab_port *up =
 493		container_of(port, struct uart_sunsab_port, port);
 494
 495	up->interrupt_mask0 |= SAB82532_IMR0_TCD;
 496	writeb(up->interrupt_mask1, &up->regs->w.imr0);
 497}
 498
 
 
 
 
 
 
 499/* port->lock is not held.  */
 500static void sunsab_break_ctl(struct uart_port *port, int break_state)
 501{
 502	struct uart_sunsab_port *up =
 503		container_of(port, struct uart_sunsab_port, port);
 504	unsigned long flags;
 505	unsigned char val;
 506
 507	spin_lock_irqsave(&up->port.lock, flags);
 508
 509	val = up->cached_dafo;
 510	if (break_state)
 511		val |= SAB82532_DAFO_XBRK;
 512	else
 513		val &= ~SAB82532_DAFO_XBRK;
 514	up->cached_dafo = val;
 515
 516	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 517	if (test_bit(SAB82532_XPR, &up->irqflags))
 518		sunsab_tx_idle(up);
 519
 520	spin_unlock_irqrestore(&up->port.lock, flags);
 521}
 522
 523/* port->lock is not held.  */
 524static int sunsab_startup(struct uart_port *port)
 525{
 526	struct uart_sunsab_port *up =
 527		container_of(port, struct uart_sunsab_port, port);
 528	unsigned long flags;
 529	unsigned char tmp;
 530	int err = request_irq(up->port.irq, sunsab_interrupt,
 531			      IRQF_SHARED, "sab", up);
 532	if (err)
 533		return err;
 534
 535	spin_lock_irqsave(&up->port.lock, flags);
 536
 537	/*
 538	 * Wait for any commands or immediate characters
 539	 */
 540	sunsab_cec_wait(up);
 541	sunsab_tec_wait(up);
 542
 543	/*
 544	 * Clear the FIFO buffers.
 545	 */
 546	writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
 547	sunsab_cec_wait(up);
 548	writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
 549
 550	/*
 551	 * Clear the interrupt registers.
 552	 */
 553	(void) readb(&up->regs->r.isr0);
 554	(void) readb(&up->regs->r.isr1);
 555
 556	/*
 557	 * Now, initialize the UART 
 558	 */
 559	writeb(0, &up->regs->w.ccr0);				/* power-down */
 560	writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
 561	       SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
 562	writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
 563	writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
 564	       SAB82532_CCR2_TOE, &up->regs->w.ccr2);
 565	writeb(0, &up->regs->w.ccr3);
 566	writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
 567	up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
 568			   SAB82532_MODE_RAC);
 569	writeb(up->cached_mode, &up->regs->w.mode);
 570	writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
 571	
 572	tmp = readb(&up->regs->rw.ccr0);
 573	tmp |= SAB82532_CCR0_PU;	/* power-up */
 574	writeb(tmp, &up->regs->rw.ccr0);
 575
 576	/*
 577	 * Finally, enable interrupts
 578	 */
 579	up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 580			       SAB82532_IMR0_PLLA);
 581	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 582	up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 583			       SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 584			       SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 585			       SAB82532_IMR1_XPR);
 586	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 587	set_bit(SAB82532_ALLS, &up->irqflags);
 588	set_bit(SAB82532_XPR, &up->irqflags);
 589
 590	spin_unlock_irqrestore(&up->port.lock, flags);
 591
 592	return 0;
 593}
 594
 595/* port->lock is not held.  */
 596static void sunsab_shutdown(struct uart_port *port)
 597{
 598	struct uart_sunsab_port *up =
 599		container_of(port, struct uart_sunsab_port, port);
 600	unsigned long flags;
 601
 602	spin_lock_irqsave(&up->port.lock, flags);
 603
 604	/* Disable Interrupts */
 605	up->interrupt_mask0 = 0xff;
 606	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 607	up->interrupt_mask1 = 0xff;
 608	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 609
 610	/* Disable break condition */
 611	up->cached_dafo = readb(&up->regs->rw.dafo);
 612	up->cached_dafo &= ~SAB82532_DAFO_XBRK;
 613	writeb(up->cached_dafo, &up->regs->rw.dafo);
 614
 615	/* Disable Receiver */	
 616	up->cached_mode &= ~SAB82532_MODE_RAC;
 617	writeb(up->cached_mode, &up->regs->rw.mode);
 618
 619	/*
 620	 * XXX FIXME
 621	 *
 622	 * If the chip is powered down here the system hangs/crashes during
 623	 * reboot or shutdown.  This needs to be investigated further,
 624	 * similar behaviour occurs in 2.4 when the driver is configured
 625	 * as a module only.  One hint may be that data is sometimes
 626	 * transmitted at 9600 baud during shutdown (regardless of the
 627	 * speed the chip was configured for when the port was open).
 628	 */
 629#if 0
 630	/* Power Down */	
 631	tmp = readb(&up->regs->rw.ccr0);
 632	tmp &= ~SAB82532_CCR0_PU;
 633	writeb(tmp, &up->regs->rw.ccr0);
 634#endif
 635
 636	spin_unlock_irqrestore(&up->port.lock, flags);
 637	free_irq(up->port.irq, up);
 638}
 639
 640/*
 641 * This is used to figure out the divisor speeds.
 642 *
 643 * The formula is:    Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
 644 *
 645 * with               0 <= N < 64 and 0 <= M < 16
 646 */
 647
 648static void calc_ebrg(int baud, int *n_ret, int *m_ret)
 649{
 650	int	n, m;
 651
 652	if (baud == 0) {
 653		*n_ret = 0;
 654		*m_ret = 0;
 655		return;
 656	}
 657     
 658	/*
 659	 * We scale numbers by 10 so that we get better accuracy
 660	 * without having to use floating point.  Here we increment m
 661	 * until n is within the valid range.
 662	 */
 663	n = (SAB_BASE_BAUD * 10) / baud;
 664	m = 0;
 665	while (n >= 640) {
 666		n = n / 2;
 667		m++;
 668	}
 669	n = (n+5) / 10;
 670	/*
 671	 * We try very hard to avoid speeds with M == 0 since they may
 672	 * not work correctly for XTAL frequences above 10 MHz.
 673	 */
 674	if ((m == 0) && ((n & 1) == 0)) {
 675		n = n / 2;
 676		m++;
 677	}
 678	*n_ret = n - 1;
 679	*m_ret = m;
 680}
 681
 682/* Internal routine, port->lock is held and local interrupts are disabled.  */
 683static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
 684				  unsigned int iflag, unsigned int baud,
 685				  unsigned int quot)
 686{
 687	unsigned char dafo;
 688	int bits, n, m;
 689
 690	/* Byte size and parity */
 691	switch (cflag & CSIZE) {
 692	      case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 693	      case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
 694	      case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
 695	      case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
 696	      /* Never happens, but GCC is too dumb to figure it out */
 697	      default:  dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 698	}
 699
 700	if (cflag & CSTOPB) {
 701		dafo |= SAB82532_DAFO_STOP;
 702		bits++;
 703	}
 704
 705	if (cflag & PARENB) {
 706		dafo |= SAB82532_DAFO_PARE;
 707		bits++;
 708	}
 709
 710	if (cflag & PARODD) {
 711		dafo |= SAB82532_DAFO_PAR_ODD;
 712	} else {
 713		dafo |= SAB82532_DAFO_PAR_EVEN;
 714	}
 715	up->cached_dafo = dafo;
 716
 717	calc_ebrg(baud, &n, &m);
 718
 719	up->cached_ebrg = n | (m << 6);
 720
 721	up->tec_timeout = (10 * 1000000) / baud;
 722	up->cec_timeout = up->tec_timeout >> 2;
 723
 724	/* CTS flow control flags */
 725	/* We encode read_status_mask and ignore_status_mask like so:
 726	 *
 727	 * ---------------------
 728	 * | ... | ISR1 | ISR0 |
 729	 * ---------------------
 730	 *  ..    15   8 7    0
 731	 */
 732
 733	up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 734				     SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
 735				     SAB82532_ISR0_CDSC);
 736	up->port.read_status_mask |= (SAB82532_ISR1_CSC |
 737				      SAB82532_ISR1_ALLS |
 738				      SAB82532_ISR1_XPR) << 8;
 739	if (iflag & INPCK)
 740		up->port.read_status_mask |= (SAB82532_ISR0_PERR |
 741					      SAB82532_ISR0_FERR);
 742	if (iflag & (IGNBRK | BRKINT | PARMRK))
 743		up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
 744
 745	/*
 746	 * Characteres to ignore
 747	 */
 748	up->port.ignore_status_mask = 0;
 749	if (iflag & IGNPAR)
 750		up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
 751						SAB82532_ISR0_FERR);
 752	if (iflag & IGNBRK) {
 753		up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
 754		/*
 755		 * If we're ignoring parity and break indicators,
 756		 * ignore overruns too (for real raw support).
 757		 */
 758		if (iflag & IGNPAR)
 759			up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
 760	}
 761
 762	/*
 763	 * ignore all characters if CREAD is not set
 764	 */
 765	if ((cflag & CREAD) == 0)
 766		up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
 767						SAB82532_ISR0_TCD);
 768
 769	uart_update_timeout(&up->port, cflag,
 770			    (up->port.uartclk / (16 * quot)));
 771
 772	/* Now schedule a register update when the chip's
 773	 * transmitter is idle.
 774	 */
 775	up->cached_mode |= SAB82532_MODE_RAC;
 776	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 777	if (test_bit(SAB82532_XPR, &up->irqflags))
 778		sunsab_tx_idle(up);
 779}
 780
 781/* port->lock is not held.  */
 782static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
 783			       struct ktermios *old)
 784{
 785	struct uart_sunsab_port *up =
 786		container_of(port, struct uart_sunsab_port, port);
 787	unsigned long flags;
 788	unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
 789	unsigned int quot = uart_get_divisor(port, baud);
 790
 791	spin_lock_irqsave(&up->port.lock, flags);
 792	sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
 793	spin_unlock_irqrestore(&up->port.lock, flags);
 794}
 795
 796static const char *sunsab_type(struct uart_port *port)
 797{
 798	struct uart_sunsab_port *up = (void *)port;
 799	static char buf[36];
 800	
 801	sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
 802	return buf;
 803}
 804
 805static void sunsab_release_port(struct uart_port *port)
 806{
 807}
 808
 809static int sunsab_request_port(struct uart_port *port)
 810{
 811	return 0;
 812}
 813
 814static void sunsab_config_port(struct uart_port *port, int flags)
 815{
 816}
 817
 818static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
 819{
 820	return -EINVAL;
 821}
 822
 823static const struct uart_ops sunsab_pops = {
 824	.tx_empty	= sunsab_tx_empty,
 825	.set_mctrl	= sunsab_set_mctrl,
 826	.get_mctrl	= sunsab_get_mctrl,
 827	.stop_tx	= sunsab_stop_tx,
 828	.start_tx	= sunsab_start_tx,
 829	.send_xchar	= sunsab_send_xchar,
 830	.stop_rx	= sunsab_stop_rx,
 
 831	.break_ctl	= sunsab_break_ctl,
 832	.startup	= sunsab_startup,
 833	.shutdown	= sunsab_shutdown,
 834	.set_termios	= sunsab_set_termios,
 835	.type		= sunsab_type,
 836	.release_port	= sunsab_release_port,
 837	.request_port	= sunsab_request_port,
 838	.config_port	= sunsab_config_port,
 839	.verify_port	= sunsab_verify_port,
 840};
 841
 842static struct uart_driver sunsab_reg = {
 843	.owner			= THIS_MODULE,
 844	.driver_name		= "sunsab",
 845	.dev_name		= "ttyS",
 846	.major			= TTY_MAJOR,
 847};
 848
 849static struct uart_sunsab_port *sunsab_ports;
 850
 851#ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
 852
 853static void sunsab_console_putchar(struct uart_port *port, int c)
 854{
 855	struct uart_sunsab_port *up =
 856		container_of(port, struct uart_sunsab_port, port);
 857
 858	sunsab_tec_wait(up);
 859	writeb(c, &up->regs->w.tic);
 860}
 861
 862static void sunsab_console_write(struct console *con, const char *s, unsigned n)
 863{
 864	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 865	unsigned long flags;
 866	int locked = 1;
 867
 868	if (up->port.sysrq || oops_in_progress)
 869		locked = spin_trylock_irqsave(&up->port.lock, flags);
 870	else
 871		spin_lock_irqsave(&up->port.lock, flags);
 872
 873	uart_console_write(&up->port, s, n, sunsab_console_putchar);
 874	sunsab_tec_wait(up);
 875
 876	if (locked)
 877		spin_unlock_irqrestore(&up->port.lock, flags);
 878}
 879
 880static int sunsab_console_setup(struct console *con, char *options)
 881{
 882	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 883	unsigned long flags;
 884	unsigned int baud, quot;
 885
 886	/*
 887	 * The console framework calls us for each and every port
 888	 * registered. Defer the console setup until the requested
 889	 * port has been properly discovered. A bit of a hack,
 890	 * though...
 891	 */
 892	if (up->port.type != PORT_SUNSAB)
 893		return -1;
 894
 895	printk("Console: ttyS%d (SAB82532)\n",
 896	       (sunsab_reg.minor - 64) + con->index);
 897
 898	sunserial_console_termios(con, up->port.dev->of_node);
 899
 900	switch (con->cflag & CBAUD) {
 901	case B150: baud = 150; break;
 902	case B300: baud = 300; break;
 903	case B600: baud = 600; break;
 904	case B1200: baud = 1200; break;
 905	case B2400: baud = 2400; break;
 906	case B4800: baud = 4800; break;
 907	default: case B9600: baud = 9600; break;
 908	case B19200: baud = 19200; break;
 909	case B38400: baud = 38400; break;
 910	case B57600: baud = 57600; break;
 911	case B115200: baud = 115200; break;
 912	case B230400: baud = 230400; break;
 913	case B460800: baud = 460800; break;
 914	}
 915
 916	/*
 917	 * Temporary fix.
 918	 */
 919	spin_lock_init(&up->port.lock);
 920
 921	/*
 922	 * Initialize the hardware
 923	 */
 924	sunsab_startup(&up->port);
 925
 926	spin_lock_irqsave(&up->port.lock, flags);
 927
 928	/*
 929	 * Finally, enable interrupts
 930	 */
 931	up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 932				SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
 933	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 934	up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 935				SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 936				SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 937				SAB82532_IMR1_XPR;
 938	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 939
 940	quot = uart_get_divisor(&up->port, baud);
 941	sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
 942	sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
 943
 944	spin_unlock_irqrestore(&up->port.lock, flags);
 945	
 946	return 0;
 947}
 948
 949static struct console sunsab_console = {
 950	.name	=	"ttyS",
 951	.write	=	sunsab_console_write,
 952	.device	=	uart_console_device,
 953	.setup	=	sunsab_console_setup,
 954	.flags	=	CON_PRINTBUFFER,
 955	.index	=	-1,
 956	.data	=	&sunsab_reg,
 957};
 958
 959static inline struct console *SUNSAB_CONSOLE(void)
 960{
 961	return &sunsab_console;
 962}
 963#else
 964#define SUNSAB_CONSOLE()	(NULL)
 965#define sunsab_console_init()	do { } while (0)
 966#endif
 967
 968static int sunsab_init_one(struct uart_sunsab_port *up,
 969				     struct platform_device *op,
 970				     unsigned long offset,
 971				     int line)
 972{
 973	up->port.line = line;
 974	up->port.dev = &op->dev;
 975
 976	up->port.mapbase = op->resource[0].start + offset;
 977	up->port.membase = of_ioremap(&op->resource[0], offset,
 978				      sizeof(union sab82532_async_regs),
 979				      "sab");
 980	if (!up->port.membase)
 981		return -ENOMEM;
 982	up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
 983
 984	up->port.irq = op->archdata.irqs[0];
 985
 986	up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
 987	up->port.iotype = UPIO_MEM;
 988
 989	writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
 990
 991	up->port.ops = &sunsab_pops;
 992	up->port.type = PORT_SUNSAB;
 993	up->port.uartclk = SAB_BASE_BAUD;
 994
 995	up->type = readb(&up->regs->r.vstr) & 0x0f;
 996	writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
 997	writeb(0xff, &up->regs->w.pim);
 998	if ((up->port.line & 0x1) == 0) {
 999		up->pvr_dsr_bit = (1 << 0);
1000		up->pvr_dtr_bit = (1 << 1);
1001		up->gis_shift = 2;
1002	} else {
1003		up->pvr_dsr_bit = (1 << 3);
1004		up->pvr_dtr_bit = (1 << 2);
1005		up->gis_shift = 0;
1006	}
1007	up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
1008	writeb(up->cached_pvr, &up->regs->w.pvr);
1009	up->cached_mode = readb(&up->regs->rw.mode);
1010	up->cached_mode |= SAB82532_MODE_FRTS;
1011	writeb(up->cached_mode, &up->regs->rw.mode);
1012	up->cached_mode |= SAB82532_MODE_RTS;
1013	writeb(up->cached_mode, &up->regs->rw.mode);
1014
1015	up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
1016	up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
1017
1018	return 0;
1019}
1020
1021static int sab_probe(struct platform_device *op)
1022{
1023	static int inst;
1024	struct uart_sunsab_port *up;
1025	int err;
1026
1027	up = &sunsab_ports[inst * 2];
1028
1029	err = sunsab_init_one(&up[0], op,
1030			      0,
1031			      (inst * 2) + 0);
1032	if (err)
1033		goto out;
1034
1035	err = sunsab_init_one(&up[1], op,
1036			      sizeof(union sab82532_async_regs),
1037			      (inst * 2) + 1);
1038	if (err)
1039		goto out1;
1040
1041	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1042				&sunsab_reg, up[0].port.line,
1043				false);
1044
1045	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1046				&sunsab_reg, up[1].port.line,
1047				false);
1048
1049	err = uart_add_one_port(&sunsab_reg, &up[0].port);
1050	if (err)
1051		goto out2;
1052
1053	err = uart_add_one_port(&sunsab_reg, &up[1].port);
1054	if (err)
1055		goto out3;
1056
1057	platform_set_drvdata(op, &up[0]);
1058
1059	inst++;
1060
1061	return 0;
1062
1063out3:
1064	uart_remove_one_port(&sunsab_reg, &up[0].port);
1065out2:
1066	of_iounmap(&op->resource[0],
1067		   up[1].port.membase,
1068		   sizeof(union sab82532_async_regs));
1069out1:
1070	of_iounmap(&op->resource[0],
1071		   up[0].port.membase,
1072		   sizeof(union sab82532_async_regs));
1073out:
1074	return err;
1075}
1076
1077static int sab_remove(struct platform_device *op)
1078{
1079	struct uart_sunsab_port *up = platform_get_drvdata(op);
1080
1081	uart_remove_one_port(&sunsab_reg, &up[1].port);
1082	uart_remove_one_port(&sunsab_reg, &up[0].port);
1083	of_iounmap(&op->resource[0],
1084		   up[1].port.membase,
1085		   sizeof(union sab82532_async_regs));
1086	of_iounmap(&op->resource[0],
1087		   up[0].port.membase,
1088		   sizeof(union sab82532_async_regs));
1089
1090	return 0;
1091}
1092
1093static const struct of_device_id sab_match[] = {
1094	{
1095		.name = "se",
1096	},
1097	{
1098		.name = "serial",
1099		.compatible = "sab82532",
1100	},
1101	{},
1102};
1103MODULE_DEVICE_TABLE(of, sab_match);
1104
1105static struct platform_driver sab_driver = {
1106	.driver = {
1107		.name = "sab",
 
1108		.of_match_table = sab_match,
1109	},
1110	.probe		= sab_probe,
1111	.remove		= sab_remove,
1112};
1113
1114static int __init sunsab_init(void)
1115{
1116	struct device_node *dp;
1117	int err;
1118	int num_channels = 0;
1119
1120	for_each_node_by_name(dp, "se")
1121		num_channels += 2;
1122	for_each_node_by_name(dp, "serial") {
1123		if (of_device_is_compatible(dp, "sab82532"))
1124			num_channels += 2;
1125	}
1126
1127	if (num_channels) {
1128		sunsab_ports = kcalloc(num_channels,
1129				       sizeof(struct uart_sunsab_port),
1130				       GFP_KERNEL);
1131		if (!sunsab_ports)
1132			return -ENOMEM;
1133
1134		err = sunserial_register_minors(&sunsab_reg, num_channels);
1135		if (err) {
1136			kfree(sunsab_ports);
1137			sunsab_ports = NULL;
1138
1139			return err;
1140		}
1141	}
1142
1143	return platform_driver_register(&sab_driver);
1144}
1145
1146static void __exit sunsab_exit(void)
1147{
1148	platform_driver_unregister(&sab_driver);
1149	if (sunsab_reg.nr) {
1150		sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
1151	}
1152
1153	kfree(sunsab_ports);
1154	sunsab_ports = NULL;
1155}
1156
1157module_init(sunsab_init);
1158module_exit(sunsab_exit);
1159
1160MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1161MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1162MODULE_LICENSE("GPL");
v3.15
 
   1/* sunsab.c: ASYNC Driver for the SIEMENS SAB82532 DUSCC.
   2 *
   3 * Copyright (C) 1997  Eddie C. Dost  (ecd@skynet.be)
   4 * Copyright (C) 2002, 2006  David S. Miller (davem@davemloft.net)
   5 *
   6 * Rewrote buffer handling to use CIRC(Circular Buffer) macros.
   7 *   Maxim Krasnyanskiy <maxk@qualcomm.com>
   8 *
   9 * Fixed to use tty_get_baud_rate, and to allow for arbitrary baud
  10 * rates to be programmed into the UART.  Also eliminated a lot of
  11 * duplicated code in the console setup.
  12 *   Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12
  13 *
  14 * Ported to new 2.5.x UART layer.
  15 *   David S. Miller <davem@davemloft.net>
  16 */
  17
  18#include <linux/module.h>
  19#include <linux/kernel.h>
  20#include <linux/errno.h>
  21#include <linux/tty.h>
  22#include <linux/tty_flip.h>
  23#include <linux/major.h>
  24#include <linux/string.h>
  25#include <linux/ptrace.h>
  26#include <linux/ioport.h>
  27#include <linux/circ_buf.h>
  28#include <linux/serial.h>
  29#include <linux/sysrq.h>
  30#include <linux/console.h>
  31#include <linux/spinlock.h>
  32#include <linux/slab.h>
  33#include <linux/delay.h>
  34#include <linux/init.h>
  35#include <linux/of_device.h>
  36
  37#include <asm/io.h>
  38#include <asm/irq.h>
  39#include <asm/prom.h>
  40#include <asm/setup.h>
  41
  42#if defined(CONFIG_SERIAL_SUNSAB_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  43#define SUPPORT_SYSRQ
  44#endif
  45
  46#include <linux/serial_core.h>
  47#include <linux/sunserialcore.h>
  48
  49#include "sunsab.h"
  50
  51struct uart_sunsab_port {
  52	struct uart_port		port;		/* Generic UART port	*/
  53	union sab82532_async_regs	__iomem *regs;	/* Chip registers	*/
  54	unsigned long			irqflags;	/* IRQ state flags	*/
  55	int				dsr;		/* Current DSR state	*/
  56	unsigned int			cec_timeout;	/* Chip poll timeout... */
  57	unsigned int			tec_timeout;	/* likewise		*/
  58	unsigned char			interrupt_mask0;/* ISR0 masking		*/
  59	unsigned char			interrupt_mask1;/* ISR1 masking		*/
  60	unsigned char			pvr_dtr_bit;	/* Which PVR bit is DTR */
  61	unsigned char			pvr_dsr_bit;	/* Which PVR bit is DSR */
  62	unsigned int			gis_shift;
  63	int				type;		/* SAB82532 version	*/
  64
  65	/* Setting configuration bits while the transmitter is active
  66	 * can cause garbage characters to get emitted by the chip.
  67	 * Therefore, we cache such writes here and do the real register
  68	 * write the next time the transmitter becomes idle.
  69	 */
  70	unsigned int			cached_ebrg;
  71	unsigned char			cached_mode;
  72	unsigned char			cached_pvr;
  73	unsigned char			cached_dafo;
  74};
  75
  76/*
  77 * This assumes you have a 29.4912 MHz clock for your UART.
  78 */
  79#define SAB_BASE_BAUD ( 29491200 / 16 )
  80
  81static char *sab82532_version[16] = {
  82	"V1.0", "V2.0", "V3.2", "V(0x03)",
  83	"V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)",
  84	"V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)",
  85	"V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)"
  86};
  87
  88#define SAB82532_MAX_TEC_TIMEOUT 200000	/* 1 character time (at 50 baud) */
  89#define SAB82532_MAX_CEC_TIMEOUT  50000	/* 2.5 TX CLKs (at 50 baud) */
  90
  91#define SAB82532_RECV_FIFO_SIZE	32      /* Standard async fifo sizes */
  92#define SAB82532_XMIT_FIFO_SIZE	32
  93
  94static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up)
  95{
  96	int timeout = up->tec_timeout;
  97
  98	while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout)
  99		udelay(1);
 100}
 101
 102static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
 103{
 104	int timeout = up->cec_timeout;
 105
 106	while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout)
 107		udelay(1);
 108}
 109
 110static struct tty_port *
 111receive_chars(struct uart_sunsab_port *up,
 112	      union sab82532_irq_status *stat)
 113{
 114	struct tty_port *port = NULL;
 115	unsigned char buf[32];
 116	int saw_console_brk = 0;
 117	int free_fifo = 0;
 118	int count = 0;
 119	int i;
 120
 121	if (up->port.state != NULL)		/* Unopened serial console */
 122		port = &up->port.state->port;
 123
 124	/* Read number of BYTES (Character + Status) available. */
 125	if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
 126		count = SAB82532_RECV_FIFO_SIZE;
 127		free_fifo++;
 128	}
 129
 130	if (stat->sreg.isr0 & SAB82532_ISR0_TCD) {
 131		count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1);
 132		free_fifo++;
 133	}
 134
 135	/* Issue a FIFO read command in case we where idle. */
 136	if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
 137		sunsab_cec_wait(up);
 138		writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
 139		return port;
 140	}
 141
 142	if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 143		free_fifo++;
 144
 145	/* Read the FIFO. */
 146	for (i = 0; i < count; i++)
 147		buf[i] = readb(&up->regs->r.rfifo[i]);
 148
 149	/* Issue Receive Message Complete command. */
 150	if (free_fifo) {
 151		sunsab_cec_wait(up);
 152		writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr);
 153	}
 154
 155	/* Count may be zero for BRK, so we check for it here */
 156	if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) &&
 157	    (up->port.line == up->port.cons->index))
 158		saw_console_brk = 1;
 159
 
 
 
 
 
 
 
 
 
 160	for (i = 0; i < count; i++) {
 161		unsigned char ch = buf[i], flag;
 162
 163		flag = TTY_NORMAL;
 164		up->port.icount.rx++;
 165
 166		if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
 167						SAB82532_ISR0_FERR |
 168						SAB82532_ISR0_RFO)) ||
 169		    unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 170			/*
 171			 * For statistics only
 172			 */
 173			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 174				stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 175						     SAB82532_ISR0_FERR);
 176				up->port.icount.brk++;
 177				/*
 178				 * We do the SysRQ and SAK checking
 179				 * here because otherwise the break
 180				 * may get masked by ignore_status_mask
 181				 * or read_status_mask.
 182				 */
 183				if (uart_handle_break(&up->port))
 184					continue;
 185			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 186				up->port.icount.parity++;
 187			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 188				up->port.icount.frame++;
 189			if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 190				up->port.icount.overrun++;
 191
 192			/*
 193			 * Mask off conditions which should be ingored.
 194			 */
 195			stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
 196			stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
 197
 198			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 199				flag = TTY_BREAK;
 200			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 201				flag = TTY_PARITY;
 202			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 203				flag = TTY_FRAME;
 204		}
 205
 206		if (uart_handle_sysrq_char(&up->port, ch) || !port)
 207			continue;
 208
 209		if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
 210		    (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
 211			tty_insert_flip_char(port, ch, flag);
 212		if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 213			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 214	}
 215
 216	if (saw_console_brk)
 217		sun_do_break();
 218
 219	return port;
 220}
 221
 222static void sunsab_stop_tx(struct uart_port *);
 223static void sunsab_tx_idle(struct uart_sunsab_port *);
 224
 225static void transmit_chars(struct uart_sunsab_port *up,
 226			   union sab82532_irq_status *stat)
 227{
 228	struct circ_buf *xmit = &up->port.state->xmit;
 229	int i;
 230
 231	if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
 232		up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
 233		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 234		set_bit(SAB82532_ALLS, &up->irqflags);
 235	}
 236
 237#if 0 /* bde@nwlink.com says this check causes problems */
 238	if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
 239		return;
 240#endif
 241
 242	if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
 243		return;
 244
 245	set_bit(SAB82532_XPR, &up->irqflags);
 246	sunsab_tx_idle(up);
 247
 248	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 249		up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 250		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 251		return;
 252	}
 253
 254	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 255	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 256	clear_bit(SAB82532_ALLS, &up->irqflags);
 257
 258	/* Stuff 32 bytes into Transmit FIFO. */
 259	clear_bit(SAB82532_XPR, &up->irqflags);
 260	for (i = 0; i < up->port.fifosize; i++) {
 261		writeb(xmit->buf[xmit->tail],
 262		       &up->regs->w.xfifo[i]);
 263		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 264		up->port.icount.tx++;
 265		if (uart_circ_empty(xmit))
 266			break;
 267	}
 268
 269	/* Issue a Transmit Frame command. */
 270	sunsab_cec_wait(up);
 271	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 272
 273	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 274		uart_write_wakeup(&up->port);
 275
 276	if (uart_circ_empty(xmit))
 277		sunsab_stop_tx(&up->port);
 278}
 279
 280static void check_status(struct uart_sunsab_port *up,
 281			 union sab82532_irq_status *stat)
 282{
 283	if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
 284		uart_handle_dcd_change(&up->port,
 285				       !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
 286
 287	if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
 288		uart_handle_cts_change(&up->port,
 289				       (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
 290
 291	if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
 292		up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
 293		up->port.icount.dsr++;
 294	}
 295
 296	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 297}
 298
 299static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
 300{
 301	struct uart_sunsab_port *up = dev_id;
 302	struct tty_port *port = NULL;
 303	union sab82532_irq_status status;
 304	unsigned long flags;
 305	unsigned char gis;
 306
 307	spin_lock_irqsave(&up->port.lock, flags);
 308
 309	status.stat = 0;
 310	gis = readb(&up->regs->r.gis) >> up->gis_shift;
 311	if (gis & 1)
 312		status.sreg.isr0 = readb(&up->regs->r.isr0);
 313	if (gis & 2)
 314		status.sreg.isr1 = readb(&up->regs->r.isr1);
 315
 316	if (status.stat) {
 317		if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 318					 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
 319		    (status.sreg.isr1 & SAB82532_ISR1_BRK))
 320			port = receive_chars(up, &status);
 321		if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
 322		    (status.sreg.isr1 & SAB82532_ISR1_CSC))
 323			check_status(up, &status);
 324		if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
 325			transmit_chars(up, &status);
 326	}
 327
 328	spin_unlock_irqrestore(&up->port.lock, flags);
 329
 330	if (port)
 331		tty_flip_buffer_push(port);
 332
 333	return IRQ_HANDLED;
 334}
 335
 336/* port->lock is not held.  */
 337static unsigned int sunsab_tx_empty(struct uart_port *port)
 338{
 339	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 340	int ret;
 341
 342	/* Do not need a lock for a state test like this.  */
 343	if (test_bit(SAB82532_ALLS, &up->irqflags))
 344		ret = TIOCSER_TEMT;
 345	else
 346		ret = 0;
 347
 348	return ret;
 349}
 350
 351/* port->lock held by caller.  */
 352static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
 353{
 354	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 355
 356	if (mctrl & TIOCM_RTS) {
 357		up->cached_mode &= ~SAB82532_MODE_FRTS;
 358		up->cached_mode |= SAB82532_MODE_RTS;
 359	} else {
 360		up->cached_mode |= (SAB82532_MODE_FRTS |
 361				    SAB82532_MODE_RTS);
 362	}
 363	if (mctrl & TIOCM_DTR) {
 364		up->cached_pvr &= ~(up->pvr_dtr_bit);
 365	} else {
 366		up->cached_pvr |= up->pvr_dtr_bit;
 367	}
 368
 369	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 370	if (test_bit(SAB82532_XPR, &up->irqflags))
 371		sunsab_tx_idle(up);
 372}
 373
 374/* port->lock is held by caller and interrupts are disabled.  */
 375static unsigned int sunsab_get_mctrl(struct uart_port *port)
 376{
 377	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 378	unsigned char val;
 379	unsigned int result;
 380
 381	result = 0;
 382
 383	val = readb(&up->regs->r.pvr);
 384	result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
 385
 386	val = readb(&up->regs->r.vstr);
 387	result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
 388
 389	val = readb(&up->regs->r.star);
 390	result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
 391
 392	return result;
 393}
 394
 395/* port->lock held by caller.  */
 396static void sunsab_stop_tx(struct uart_port *port)
 397{
 398	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 399
 400	up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 401	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 402}
 403
 404/* port->lock held by caller.  */
 405static void sunsab_tx_idle(struct uart_sunsab_port *up)
 406{
 407	if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
 408		u8 tmp;
 409
 410		clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
 411		writeb(up->cached_mode, &up->regs->rw.mode);
 412		writeb(up->cached_pvr, &up->regs->rw.pvr);
 413		writeb(up->cached_dafo, &up->regs->w.dafo);
 414
 415		writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
 416		tmp = readb(&up->regs->rw.ccr2);
 417		tmp &= ~0xc0;
 418		tmp |= (up->cached_ebrg >> 2) & 0xc0;
 419		writeb(tmp, &up->regs->rw.ccr2);
 420	}
 421}
 422
 423/* port->lock held by caller.  */
 424static void sunsab_start_tx(struct uart_port *port)
 425{
 426	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 427	struct circ_buf *xmit = &up->port.state->xmit;
 428	int i;
 429
 
 
 
 430	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 431	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 432	
 433	if (!test_bit(SAB82532_XPR, &up->irqflags))
 434		return;
 435
 436	clear_bit(SAB82532_ALLS, &up->irqflags);
 437	clear_bit(SAB82532_XPR, &up->irqflags);
 438
 439	for (i = 0; i < up->port.fifosize; i++) {
 440		writeb(xmit->buf[xmit->tail],
 441		       &up->regs->w.xfifo[i]);
 442		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 443		up->port.icount.tx++;
 444		if (uart_circ_empty(xmit))
 445			break;
 446	}
 447
 448	/* Issue a Transmit Frame command.  */
 449	sunsab_cec_wait(up);
 450	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 451}
 452
 453/* port->lock is not held.  */
 454static void sunsab_send_xchar(struct uart_port *port, char ch)
 455{
 456	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 457	unsigned long flags;
 458
 
 
 
 459	spin_lock_irqsave(&up->port.lock, flags);
 460
 461	sunsab_tec_wait(up);
 462	writeb(ch, &up->regs->w.tic);
 463
 464	spin_unlock_irqrestore(&up->port.lock, flags);
 465}
 466
 467/* port->lock held by caller.  */
 468static void sunsab_stop_rx(struct uart_port *port)
 469{
 470	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 471
 472	up->interrupt_mask0 |= SAB82532_IMR0_TCD;
 473	writeb(up->interrupt_mask1, &up->regs->w.imr0);
 474}
 475
 476/* port->lock held by caller.  */
 477static void sunsab_enable_ms(struct uart_port *port)
 478{
 479	/* For now we always receive these interrupts.  */
 480}
 481
 482/* port->lock is not held.  */
 483static void sunsab_break_ctl(struct uart_port *port, int break_state)
 484{
 485	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 486	unsigned long flags;
 487	unsigned char val;
 488
 489	spin_lock_irqsave(&up->port.lock, flags);
 490
 491	val = up->cached_dafo;
 492	if (break_state)
 493		val |= SAB82532_DAFO_XBRK;
 494	else
 495		val &= ~SAB82532_DAFO_XBRK;
 496	up->cached_dafo = val;
 497
 498	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 499	if (test_bit(SAB82532_XPR, &up->irqflags))
 500		sunsab_tx_idle(up);
 501
 502	spin_unlock_irqrestore(&up->port.lock, flags);
 503}
 504
 505/* port->lock is not held.  */
 506static int sunsab_startup(struct uart_port *port)
 507{
 508	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 509	unsigned long flags;
 510	unsigned char tmp;
 511	int err = request_irq(up->port.irq, sunsab_interrupt,
 512			      IRQF_SHARED, "sab", up);
 513	if (err)
 514		return err;
 515
 516	spin_lock_irqsave(&up->port.lock, flags);
 517
 518	/*
 519	 * Wait for any commands or immediate characters
 520	 */
 521	sunsab_cec_wait(up);
 522	sunsab_tec_wait(up);
 523
 524	/*
 525	 * Clear the FIFO buffers.
 526	 */
 527	writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
 528	sunsab_cec_wait(up);
 529	writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
 530
 531	/*
 532	 * Clear the interrupt registers.
 533	 */
 534	(void) readb(&up->regs->r.isr0);
 535	(void) readb(&up->regs->r.isr1);
 536
 537	/*
 538	 * Now, initialize the UART 
 539	 */
 540	writeb(0, &up->regs->w.ccr0);				/* power-down */
 541	writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
 542	       SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
 543	writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
 544	writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
 545	       SAB82532_CCR2_TOE, &up->regs->w.ccr2);
 546	writeb(0, &up->regs->w.ccr3);
 547	writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
 548	up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
 549			   SAB82532_MODE_RAC);
 550	writeb(up->cached_mode, &up->regs->w.mode);
 551	writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
 552	
 553	tmp = readb(&up->regs->rw.ccr0);
 554	tmp |= SAB82532_CCR0_PU;	/* power-up */
 555	writeb(tmp, &up->regs->rw.ccr0);
 556
 557	/*
 558	 * Finally, enable interrupts
 559	 */
 560	up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 561			       SAB82532_IMR0_PLLA);
 562	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 563	up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 564			       SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 565			       SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 566			       SAB82532_IMR1_XPR);
 567	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 568	set_bit(SAB82532_ALLS, &up->irqflags);
 569	set_bit(SAB82532_XPR, &up->irqflags);
 570
 571	spin_unlock_irqrestore(&up->port.lock, flags);
 572
 573	return 0;
 574}
 575
 576/* port->lock is not held.  */
 577static void sunsab_shutdown(struct uart_port *port)
 578{
 579	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 580	unsigned long flags;
 581
 582	spin_lock_irqsave(&up->port.lock, flags);
 583
 584	/* Disable Interrupts */
 585	up->interrupt_mask0 = 0xff;
 586	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 587	up->interrupt_mask1 = 0xff;
 588	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 589
 590	/* Disable break condition */
 591	up->cached_dafo = readb(&up->regs->rw.dafo);
 592	up->cached_dafo &= ~SAB82532_DAFO_XBRK;
 593	writeb(up->cached_dafo, &up->regs->rw.dafo);
 594
 595	/* Disable Receiver */	
 596	up->cached_mode &= ~SAB82532_MODE_RAC;
 597	writeb(up->cached_mode, &up->regs->rw.mode);
 598
 599	/*
 600	 * XXX FIXME
 601	 *
 602	 * If the chip is powered down here the system hangs/crashes during
 603	 * reboot or shutdown.  This needs to be investigated further,
 604	 * similar behaviour occurs in 2.4 when the driver is configured
 605	 * as a module only.  One hint may be that data is sometimes
 606	 * transmitted at 9600 baud during shutdown (regardless of the
 607	 * speed the chip was configured for when the port was open).
 608	 */
 609#if 0
 610	/* Power Down */	
 611	tmp = readb(&up->regs->rw.ccr0);
 612	tmp &= ~SAB82532_CCR0_PU;
 613	writeb(tmp, &up->regs->rw.ccr0);
 614#endif
 615
 616	spin_unlock_irqrestore(&up->port.lock, flags);
 617	free_irq(up->port.irq, up);
 618}
 619
 620/*
 621 * This is used to figure out the divisor speeds.
 622 *
 623 * The formula is:    Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
 624 *
 625 * with               0 <= N < 64 and 0 <= M < 16
 626 */
 627
 628static void calc_ebrg(int baud, int *n_ret, int *m_ret)
 629{
 630	int	n, m;
 631
 632	if (baud == 0) {
 633		*n_ret = 0;
 634		*m_ret = 0;
 635		return;
 636	}
 637     
 638	/*
 639	 * We scale numbers by 10 so that we get better accuracy
 640	 * without having to use floating point.  Here we increment m
 641	 * until n is within the valid range.
 642	 */
 643	n = (SAB_BASE_BAUD * 10) / baud;
 644	m = 0;
 645	while (n >= 640) {
 646		n = n / 2;
 647		m++;
 648	}
 649	n = (n+5) / 10;
 650	/*
 651	 * We try very hard to avoid speeds with M == 0 since they may
 652	 * not work correctly for XTAL frequences above 10 MHz.
 653	 */
 654	if ((m == 0) && ((n & 1) == 0)) {
 655		n = n / 2;
 656		m++;
 657	}
 658	*n_ret = n - 1;
 659	*m_ret = m;
 660}
 661
 662/* Internal routine, port->lock is held and local interrupts are disabled.  */
 663static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
 664				  unsigned int iflag, unsigned int baud,
 665				  unsigned int quot)
 666{
 667	unsigned char dafo;
 668	int bits, n, m;
 669
 670	/* Byte size and parity */
 671	switch (cflag & CSIZE) {
 672	      case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 673	      case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
 674	      case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
 675	      case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
 676	      /* Never happens, but GCC is too dumb to figure it out */
 677	      default:  dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 678	}
 679
 680	if (cflag & CSTOPB) {
 681		dafo |= SAB82532_DAFO_STOP;
 682		bits++;
 683	}
 684
 685	if (cflag & PARENB) {
 686		dafo |= SAB82532_DAFO_PARE;
 687		bits++;
 688	}
 689
 690	if (cflag & PARODD) {
 691		dafo |= SAB82532_DAFO_PAR_ODD;
 692	} else {
 693		dafo |= SAB82532_DAFO_PAR_EVEN;
 694	}
 695	up->cached_dafo = dafo;
 696
 697	calc_ebrg(baud, &n, &m);
 698
 699	up->cached_ebrg = n | (m << 6);
 700
 701	up->tec_timeout = (10 * 1000000) / baud;
 702	up->cec_timeout = up->tec_timeout >> 2;
 703
 704	/* CTS flow control flags */
 705	/* We encode read_status_mask and ignore_status_mask like so:
 706	 *
 707	 * ---------------------
 708	 * | ... | ISR1 | ISR0 |
 709	 * ---------------------
 710	 *  ..    15   8 7    0
 711	 */
 712
 713	up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 714				     SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
 715				     SAB82532_ISR0_CDSC);
 716	up->port.read_status_mask |= (SAB82532_ISR1_CSC |
 717				      SAB82532_ISR1_ALLS |
 718				      SAB82532_ISR1_XPR) << 8;
 719	if (iflag & INPCK)
 720		up->port.read_status_mask |= (SAB82532_ISR0_PERR |
 721					      SAB82532_ISR0_FERR);
 722	if (iflag & (BRKINT | PARMRK))
 723		up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
 724
 725	/*
 726	 * Characteres to ignore
 727	 */
 728	up->port.ignore_status_mask = 0;
 729	if (iflag & IGNPAR)
 730		up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
 731						SAB82532_ISR0_FERR);
 732	if (iflag & IGNBRK) {
 733		up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
 734		/*
 735		 * If we're ignoring parity and break indicators,
 736		 * ignore overruns too (for real raw support).
 737		 */
 738		if (iflag & IGNPAR)
 739			up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
 740	}
 741
 742	/*
 743	 * ignore all characters if CREAD is not set
 744	 */
 745	if ((cflag & CREAD) == 0)
 746		up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
 747						SAB82532_ISR0_TCD);
 748
 749	uart_update_timeout(&up->port, cflag,
 750			    (up->port.uartclk / (16 * quot)));
 751
 752	/* Now schedule a register update when the chip's
 753	 * transmitter is idle.
 754	 */
 755	up->cached_mode |= SAB82532_MODE_RAC;
 756	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 757	if (test_bit(SAB82532_XPR, &up->irqflags))
 758		sunsab_tx_idle(up);
 759}
 760
 761/* port->lock is not held.  */
 762static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
 763			       struct ktermios *old)
 764{
 765	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 766	unsigned long flags;
 767	unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
 768	unsigned int quot = uart_get_divisor(port, baud);
 769
 770	spin_lock_irqsave(&up->port.lock, flags);
 771	sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
 772	spin_unlock_irqrestore(&up->port.lock, flags);
 773}
 774
 775static const char *sunsab_type(struct uart_port *port)
 776{
 777	struct uart_sunsab_port *up = (void *)port;
 778	static char buf[36];
 779	
 780	sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
 781	return buf;
 782}
 783
 784static void sunsab_release_port(struct uart_port *port)
 785{
 786}
 787
 788static int sunsab_request_port(struct uart_port *port)
 789{
 790	return 0;
 791}
 792
 793static void sunsab_config_port(struct uart_port *port, int flags)
 794{
 795}
 796
 797static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
 798{
 799	return -EINVAL;
 800}
 801
 802static struct uart_ops sunsab_pops = {
 803	.tx_empty	= sunsab_tx_empty,
 804	.set_mctrl	= sunsab_set_mctrl,
 805	.get_mctrl	= sunsab_get_mctrl,
 806	.stop_tx	= sunsab_stop_tx,
 807	.start_tx	= sunsab_start_tx,
 808	.send_xchar	= sunsab_send_xchar,
 809	.stop_rx	= sunsab_stop_rx,
 810	.enable_ms	= sunsab_enable_ms,
 811	.break_ctl	= sunsab_break_ctl,
 812	.startup	= sunsab_startup,
 813	.shutdown	= sunsab_shutdown,
 814	.set_termios	= sunsab_set_termios,
 815	.type		= sunsab_type,
 816	.release_port	= sunsab_release_port,
 817	.request_port	= sunsab_request_port,
 818	.config_port	= sunsab_config_port,
 819	.verify_port	= sunsab_verify_port,
 820};
 821
 822static struct uart_driver sunsab_reg = {
 823	.owner			= THIS_MODULE,
 824	.driver_name		= "sunsab",
 825	.dev_name		= "ttyS",
 826	.major			= TTY_MAJOR,
 827};
 828
 829static struct uart_sunsab_port *sunsab_ports;
 830
 831#ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
 832
 833static void sunsab_console_putchar(struct uart_port *port, int c)
 834{
 835	struct uart_sunsab_port *up = (struct uart_sunsab_port *)port;
 
 836
 837	sunsab_tec_wait(up);
 838	writeb(c, &up->regs->w.tic);
 839}
 840
 841static void sunsab_console_write(struct console *con, const char *s, unsigned n)
 842{
 843	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 844	unsigned long flags;
 845	int locked = 1;
 846
 847	if (up->port.sysrq || oops_in_progress)
 848		locked = spin_trylock_irqsave(&up->port.lock, flags);
 849	else
 850		spin_lock_irqsave(&up->port.lock, flags);
 851
 852	uart_console_write(&up->port, s, n, sunsab_console_putchar);
 853	sunsab_tec_wait(up);
 854
 855	if (locked)
 856		spin_unlock_irqrestore(&up->port.lock, flags);
 857}
 858
 859static int sunsab_console_setup(struct console *con, char *options)
 860{
 861	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 862	unsigned long flags;
 863	unsigned int baud, quot;
 864
 865	/*
 866	 * The console framework calls us for each and every port
 867	 * registered. Defer the console setup until the requested
 868	 * port has been properly discovered. A bit of a hack,
 869	 * though...
 870	 */
 871	if (up->port.type != PORT_SUNSAB)
 872		return -1;
 873
 874	printk("Console: ttyS%d (SAB82532)\n",
 875	       (sunsab_reg.minor - 64) + con->index);
 876
 877	sunserial_console_termios(con, up->port.dev->of_node);
 878
 879	switch (con->cflag & CBAUD) {
 880	case B150: baud = 150; break;
 881	case B300: baud = 300; break;
 882	case B600: baud = 600; break;
 883	case B1200: baud = 1200; break;
 884	case B2400: baud = 2400; break;
 885	case B4800: baud = 4800; break;
 886	default: case B9600: baud = 9600; break;
 887	case B19200: baud = 19200; break;
 888	case B38400: baud = 38400; break;
 889	case B57600: baud = 57600; break;
 890	case B115200: baud = 115200; break;
 891	case B230400: baud = 230400; break;
 892	case B460800: baud = 460800; break;
 893	}
 894
 895	/*
 896	 * Temporary fix.
 897	 */
 898	spin_lock_init(&up->port.lock);
 899
 900	/*
 901	 * Initialize the hardware
 902	 */
 903	sunsab_startup(&up->port);
 904
 905	spin_lock_irqsave(&up->port.lock, flags);
 906
 907	/*
 908	 * Finally, enable interrupts
 909	 */
 910	up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 911				SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
 912	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 913	up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 914				SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 915				SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 916				SAB82532_IMR1_XPR;
 917	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 918
 919	quot = uart_get_divisor(&up->port, baud);
 920	sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
 921	sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
 922
 923	spin_unlock_irqrestore(&up->port.lock, flags);
 924	
 925	return 0;
 926}
 927
 928static struct console sunsab_console = {
 929	.name	=	"ttyS",
 930	.write	=	sunsab_console_write,
 931	.device	=	uart_console_device,
 932	.setup	=	sunsab_console_setup,
 933	.flags	=	CON_PRINTBUFFER,
 934	.index	=	-1,
 935	.data	=	&sunsab_reg,
 936};
 937
 938static inline struct console *SUNSAB_CONSOLE(void)
 939{
 940	return &sunsab_console;
 941}
 942#else
 943#define SUNSAB_CONSOLE()	(NULL)
 944#define sunsab_console_init()	do { } while (0)
 945#endif
 946
 947static int sunsab_init_one(struct uart_sunsab_port *up,
 948				     struct platform_device *op,
 949				     unsigned long offset,
 950				     int line)
 951{
 952	up->port.line = line;
 953	up->port.dev = &op->dev;
 954
 955	up->port.mapbase = op->resource[0].start + offset;
 956	up->port.membase = of_ioremap(&op->resource[0], offset,
 957				      sizeof(union sab82532_async_regs),
 958				      "sab");
 959	if (!up->port.membase)
 960		return -ENOMEM;
 961	up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
 962
 963	up->port.irq = op->archdata.irqs[0];
 964
 965	up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
 966	up->port.iotype = UPIO_MEM;
 967
 968	writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
 969
 970	up->port.ops = &sunsab_pops;
 971	up->port.type = PORT_SUNSAB;
 972	up->port.uartclk = SAB_BASE_BAUD;
 973
 974	up->type = readb(&up->regs->r.vstr) & 0x0f;
 975	writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
 976	writeb(0xff, &up->regs->w.pim);
 977	if ((up->port.line & 0x1) == 0) {
 978		up->pvr_dsr_bit = (1 << 0);
 979		up->pvr_dtr_bit = (1 << 1);
 980		up->gis_shift = 2;
 981	} else {
 982		up->pvr_dsr_bit = (1 << 3);
 983		up->pvr_dtr_bit = (1 << 2);
 984		up->gis_shift = 0;
 985	}
 986	up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
 987	writeb(up->cached_pvr, &up->regs->w.pvr);
 988	up->cached_mode = readb(&up->regs->rw.mode);
 989	up->cached_mode |= SAB82532_MODE_FRTS;
 990	writeb(up->cached_mode, &up->regs->rw.mode);
 991	up->cached_mode |= SAB82532_MODE_RTS;
 992	writeb(up->cached_mode, &up->regs->rw.mode);
 993
 994	up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
 995	up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
 996
 997	return 0;
 998}
 999
1000static int sab_probe(struct platform_device *op)
1001{
1002	static int inst;
1003	struct uart_sunsab_port *up;
1004	int err;
1005
1006	up = &sunsab_ports[inst * 2];
1007
1008	err = sunsab_init_one(&up[0], op,
1009			      0,
1010			      (inst * 2) + 0);
1011	if (err)
1012		goto out;
1013
1014	err = sunsab_init_one(&up[1], op,
1015			      sizeof(union sab82532_async_regs),
1016			      (inst * 2) + 1);
1017	if (err)
1018		goto out1;
1019
1020	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1021				&sunsab_reg, up[0].port.line,
1022				false);
1023
1024	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1025				&sunsab_reg, up[1].port.line,
1026				false);
1027
1028	err = uart_add_one_port(&sunsab_reg, &up[0].port);
1029	if (err)
1030		goto out2;
1031
1032	err = uart_add_one_port(&sunsab_reg, &up[1].port);
1033	if (err)
1034		goto out3;
1035
1036	platform_set_drvdata(op, &up[0]);
1037
1038	inst++;
1039
1040	return 0;
1041
1042out3:
1043	uart_remove_one_port(&sunsab_reg, &up[0].port);
1044out2:
1045	of_iounmap(&op->resource[0],
1046		   up[1].port.membase,
1047		   sizeof(union sab82532_async_regs));
1048out1:
1049	of_iounmap(&op->resource[0],
1050		   up[0].port.membase,
1051		   sizeof(union sab82532_async_regs));
1052out:
1053	return err;
1054}
1055
1056static int sab_remove(struct platform_device *op)
1057{
1058	struct uart_sunsab_port *up = platform_get_drvdata(op);
1059
1060	uart_remove_one_port(&sunsab_reg, &up[1].port);
1061	uart_remove_one_port(&sunsab_reg, &up[0].port);
1062	of_iounmap(&op->resource[0],
1063		   up[1].port.membase,
1064		   sizeof(union sab82532_async_regs));
1065	of_iounmap(&op->resource[0],
1066		   up[0].port.membase,
1067		   sizeof(union sab82532_async_regs));
1068
1069	return 0;
1070}
1071
1072static const struct of_device_id sab_match[] = {
1073	{
1074		.name = "se",
1075	},
1076	{
1077		.name = "serial",
1078		.compatible = "sab82532",
1079	},
1080	{},
1081};
1082MODULE_DEVICE_TABLE(of, sab_match);
1083
1084static struct platform_driver sab_driver = {
1085	.driver = {
1086		.name = "sab",
1087		.owner = THIS_MODULE,
1088		.of_match_table = sab_match,
1089	},
1090	.probe		= sab_probe,
1091	.remove		= sab_remove,
1092};
1093
1094static int __init sunsab_init(void)
1095{
1096	struct device_node *dp;
1097	int err;
1098	int num_channels = 0;
1099
1100	for_each_node_by_name(dp, "se")
1101		num_channels += 2;
1102	for_each_node_by_name(dp, "serial") {
1103		if (of_device_is_compatible(dp, "sab82532"))
1104			num_channels += 2;
1105	}
1106
1107	if (num_channels) {
1108		sunsab_ports = kzalloc(sizeof(struct uart_sunsab_port) *
1109				       num_channels, GFP_KERNEL);
 
1110		if (!sunsab_ports)
1111			return -ENOMEM;
1112
1113		err = sunserial_register_minors(&sunsab_reg, num_channels);
1114		if (err) {
1115			kfree(sunsab_ports);
1116			sunsab_ports = NULL;
1117
1118			return err;
1119		}
1120	}
1121
1122	return platform_driver_register(&sab_driver);
1123}
1124
1125static void __exit sunsab_exit(void)
1126{
1127	platform_driver_unregister(&sab_driver);
1128	if (sunsab_reg.nr) {
1129		sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
1130	}
1131
1132	kfree(sunsab_ports);
1133	sunsab_ports = NULL;
1134}
1135
1136module_init(sunsab_init);
1137module_exit(sunsab_exit);
1138
1139MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1140MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1141MODULE_LICENSE("GPL");