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v3.1
   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
  41#if defined(CONFIG_SERIAL_SUNSAB_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  42#define SUPPORT_SYSRQ
  43#endif
  44
  45#include <linux/serial_core.h>
 
  46
  47#include "suncore.h"
  48#include "sunsab.h"
  49
  50struct uart_sunsab_port {
  51	struct uart_port		port;		/* Generic UART port	*/
  52	union sab82532_async_regs	__iomem *regs;	/* Chip registers	*/
  53	unsigned long			irqflags;	/* IRQ state flags	*/
  54	int				dsr;		/* Current DSR state	*/
  55	unsigned int			cec_timeout;	/* Chip poll timeout... */
  56	unsigned int			tec_timeout;	/* likewise		*/
  57	unsigned char			interrupt_mask0;/* ISR0 masking		*/
  58	unsigned char			interrupt_mask1;/* ISR1 masking		*/
  59	unsigned char			pvr_dtr_bit;	/* Which PVR bit is DTR */
  60	unsigned char			pvr_dsr_bit;	/* Which PVR bit is DSR */
  61	unsigned int			gis_shift;
  62	int				type;		/* SAB82532 version	*/
  63
  64	/* Setting configuration bits while the transmitter is active
  65	 * can cause garbage characters to get emitted by the chip.
  66	 * Therefore, we cache such writes here and do the real register
  67	 * write the next time the transmitter becomes idle.
  68	 */
  69	unsigned int			cached_ebrg;
  70	unsigned char			cached_mode;
  71	unsigned char			cached_pvr;
  72	unsigned char			cached_dafo;
  73};
  74
  75/*
  76 * This assumes you have a 29.4912 MHz clock for your UART.
  77 */
  78#define SAB_BASE_BAUD ( 29491200 / 16 )
  79
  80static char *sab82532_version[16] = {
  81	"V1.0", "V2.0", "V3.2", "V(0x03)",
  82	"V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)",
  83	"V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)",
  84	"V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)"
  85};
  86
  87#define SAB82532_MAX_TEC_TIMEOUT 200000	/* 1 character time (at 50 baud) */
  88#define SAB82532_MAX_CEC_TIMEOUT  50000	/* 2.5 TX CLKs (at 50 baud) */
  89
  90#define SAB82532_RECV_FIFO_SIZE	32      /* Standard async fifo sizes */
  91#define SAB82532_XMIT_FIFO_SIZE	32
  92
  93static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up)
  94{
  95	int timeout = up->tec_timeout;
  96
  97	while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout)
  98		udelay(1);
  99}
 100
 101static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
 102{
 103	int timeout = up->cec_timeout;
 104
 105	while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout)
 106		udelay(1);
 107}
 108
 109static struct tty_struct *
 110receive_chars(struct uart_sunsab_port *up,
 111	      union sab82532_irq_status *stat)
 112{
 113	struct tty_struct *tty = NULL;
 114	unsigned char buf[32];
 115	int saw_console_brk = 0;
 116	int free_fifo = 0;
 117	int count = 0;
 118	int i;
 119
 120	if (up->port.state != NULL)		/* Unopened serial console */
 121		tty = up->port.state->port.tty;
 122
 123	/* Read number of BYTES (Character + Status) available. */
 124	if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
 125		count = SAB82532_RECV_FIFO_SIZE;
 126		free_fifo++;
 127	}
 128
 129	if (stat->sreg.isr0 & SAB82532_ISR0_TCD) {
 130		count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1);
 131		free_fifo++;
 132	}
 133
 134	/* Issue a FIFO read command in case we where idle. */
 135	if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
 136		sunsab_cec_wait(up);
 137		writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
 138		return tty;
 139	}
 140
 141	if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 142		free_fifo++;
 143
 144	/* Read the FIFO. */
 145	for (i = 0; i < count; i++)
 146		buf[i] = readb(&up->regs->r.rfifo[i]);
 147
 148	/* Issue Receive Message Complete command. */
 149	if (free_fifo) {
 150		sunsab_cec_wait(up);
 151		writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr);
 152	}
 153
 154	/* Count may be zero for BRK, so we check for it here */
 155	if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) &&
 156	    (up->port.line == up->port.cons->index))
 157		saw_console_brk = 1;
 158
 159	for (i = 0; i < count; i++) {
 160		unsigned char ch = buf[i], flag;
 161
 162		if (tty == NULL) {
 163			uart_handle_sysrq_char(&up->port, ch);
 164			continue;
 165		}
 166
 167		flag = TTY_NORMAL;
 168		up->port.icount.rx++;
 169
 170		if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
 171						SAB82532_ISR0_FERR |
 172						SAB82532_ISR0_RFO)) ||
 173		    unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 174			/*
 175			 * For statistics only
 176			 */
 177			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 178				stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 179						     SAB82532_ISR0_FERR);
 180				up->port.icount.brk++;
 181				/*
 182				 * We do the SysRQ and SAK checking
 183				 * here because otherwise the break
 184				 * may get masked by ignore_status_mask
 185				 * or read_status_mask.
 186				 */
 187				if (uart_handle_break(&up->port))
 188					continue;
 189			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 190				up->port.icount.parity++;
 191			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 192				up->port.icount.frame++;
 193			if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 194				up->port.icount.overrun++;
 195
 196			/*
 197			 * Mask off conditions which should be ingored.
 198			 */
 199			stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
 200			stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
 201
 202			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 203				flag = TTY_BREAK;
 204			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 205				flag = TTY_PARITY;
 206			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 207				flag = TTY_FRAME;
 208		}
 209
 210		if (uart_handle_sysrq_char(&up->port, ch))
 211			continue;
 212
 213		if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
 214		    (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
 215			tty_insert_flip_char(tty, ch, flag);
 216		if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 217			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
 218	}
 219
 220	if (saw_console_brk)
 221		sun_do_break();
 222
 223	return tty;
 224}
 225
 226static void sunsab_stop_tx(struct uart_port *);
 227static void sunsab_tx_idle(struct uart_sunsab_port *);
 228
 229static void transmit_chars(struct uart_sunsab_port *up,
 230			   union sab82532_irq_status *stat)
 231{
 232	struct circ_buf *xmit = &up->port.state->xmit;
 233	int i;
 234
 235	if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
 236		up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
 237		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 238		set_bit(SAB82532_ALLS, &up->irqflags);
 239	}
 240
 241#if 0 /* bde@nwlink.com says this check causes problems */
 242	if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
 243		return;
 244#endif
 245
 246	if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
 247		return;
 248
 249	set_bit(SAB82532_XPR, &up->irqflags);
 250	sunsab_tx_idle(up);
 251
 252	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 253		up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 254		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 255		return;
 256	}
 257
 258	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 259	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 260	clear_bit(SAB82532_ALLS, &up->irqflags);
 261
 262	/* Stuff 32 bytes into Transmit FIFO. */
 263	clear_bit(SAB82532_XPR, &up->irqflags);
 264	for (i = 0; i < up->port.fifosize; i++) {
 265		writeb(xmit->buf[xmit->tail],
 266		       &up->regs->w.xfifo[i]);
 267		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 268		up->port.icount.tx++;
 269		if (uart_circ_empty(xmit))
 270			break;
 271	}
 272
 273	/* Issue a Transmit Frame command. */
 274	sunsab_cec_wait(up);
 275	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 276
 277	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 278		uart_write_wakeup(&up->port);
 279
 280	if (uart_circ_empty(xmit))
 281		sunsab_stop_tx(&up->port);
 282}
 283
 284static void check_status(struct uart_sunsab_port *up,
 285			 union sab82532_irq_status *stat)
 286{
 287	if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
 288		uart_handle_dcd_change(&up->port,
 289				       !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
 290
 291	if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
 292		uart_handle_cts_change(&up->port,
 293				       (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
 294
 295	if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
 296		up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
 297		up->port.icount.dsr++;
 298	}
 299
 300	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 301}
 302
 303static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
 304{
 305	struct uart_sunsab_port *up = dev_id;
 306	struct tty_struct *tty;
 307	union sab82532_irq_status status;
 308	unsigned long flags;
 309	unsigned char gis;
 310
 311	spin_lock_irqsave(&up->port.lock, flags);
 312
 313	status.stat = 0;
 314	gis = readb(&up->regs->r.gis) >> up->gis_shift;
 315	if (gis & 1)
 316		status.sreg.isr0 = readb(&up->regs->r.isr0);
 317	if (gis & 2)
 318		status.sreg.isr1 = readb(&up->regs->r.isr1);
 319
 320	tty = NULL;
 321	if (status.stat) {
 322		if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 323					 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
 324		    (status.sreg.isr1 & SAB82532_ISR1_BRK))
 325			tty = receive_chars(up, &status);
 326		if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
 327		    (status.sreg.isr1 & SAB82532_ISR1_CSC))
 328			check_status(up, &status);
 329		if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
 330			transmit_chars(up, &status);
 331	}
 332
 333	spin_unlock_irqrestore(&up->port.lock, flags);
 334
 335	if (tty)
 336		tty_flip_buffer_push(tty);
 337
 338	return IRQ_HANDLED;
 339}
 340
 341/* port->lock is not held.  */
 342static unsigned int sunsab_tx_empty(struct uart_port *port)
 343{
 344	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 345	int ret;
 346
 347	/* Do not need a lock for a state test like this.  */
 348	if (test_bit(SAB82532_ALLS, &up->irqflags))
 349		ret = TIOCSER_TEMT;
 350	else
 351		ret = 0;
 352
 353	return ret;
 354}
 355
 356/* port->lock held by caller.  */
 357static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
 358{
 359	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 360
 361	if (mctrl & TIOCM_RTS) {
 362		up->cached_mode &= ~SAB82532_MODE_FRTS;
 363		up->cached_mode |= SAB82532_MODE_RTS;
 364	} else {
 365		up->cached_mode |= (SAB82532_MODE_FRTS |
 366				    SAB82532_MODE_RTS);
 367	}
 368	if (mctrl & TIOCM_DTR) {
 369		up->cached_pvr &= ~(up->pvr_dtr_bit);
 370	} else {
 371		up->cached_pvr |= up->pvr_dtr_bit;
 372	}
 373
 374	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 375	if (test_bit(SAB82532_XPR, &up->irqflags))
 376		sunsab_tx_idle(up);
 377}
 378
 379/* port->lock is held by caller and interrupts are disabled.  */
 380static unsigned int sunsab_get_mctrl(struct uart_port *port)
 381{
 382	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 383	unsigned char val;
 384	unsigned int result;
 385
 386	result = 0;
 387
 388	val = readb(&up->regs->r.pvr);
 389	result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
 390
 391	val = readb(&up->regs->r.vstr);
 392	result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
 393
 394	val = readb(&up->regs->r.star);
 395	result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
 396
 397	return result;
 398}
 399
 400/* port->lock held by caller.  */
 401static void sunsab_stop_tx(struct uart_port *port)
 402{
 403	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 404
 405	up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 406	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 407}
 408
 409/* port->lock held by caller.  */
 410static void sunsab_tx_idle(struct uart_sunsab_port *up)
 411{
 412	if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
 413		u8 tmp;
 414
 415		clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
 416		writeb(up->cached_mode, &up->regs->rw.mode);
 417		writeb(up->cached_pvr, &up->regs->rw.pvr);
 418		writeb(up->cached_dafo, &up->regs->w.dafo);
 419
 420		writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
 421		tmp = readb(&up->regs->rw.ccr2);
 422		tmp &= ~0xc0;
 423		tmp |= (up->cached_ebrg >> 2) & 0xc0;
 424		writeb(tmp, &up->regs->rw.ccr2);
 425	}
 426}
 427
 428/* port->lock held by caller.  */
 429static void sunsab_start_tx(struct uart_port *port)
 430{
 431	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 432	struct circ_buf *xmit = &up->port.state->xmit;
 433	int i;
 434
 435	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 436	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 437	
 438	if (!test_bit(SAB82532_XPR, &up->irqflags))
 439		return;
 440
 441	clear_bit(SAB82532_ALLS, &up->irqflags);
 442	clear_bit(SAB82532_XPR, &up->irqflags);
 443
 444	for (i = 0; i < up->port.fifosize; i++) {
 445		writeb(xmit->buf[xmit->tail],
 446		       &up->regs->w.xfifo[i]);
 447		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 448		up->port.icount.tx++;
 449		if (uart_circ_empty(xmit))
 450			break;
 451	}
 452
 453	/* Issue a Transmit Frame command.  */
 454	sunsab_cec_wait(up);
 455	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 456}
 457
 458/* port->lock is not held.  */
 459static void sunsab_send_xchar(struct uart_port *port, char ch)
 460{
 461	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 462	unsigned long flags;
 463
 464	spin_lock_irqsave(&up->port.lock, flags);
 465
 466	sunsab_tec_wait(up);
 467	writeb(ch, &up->regs->w.tic);
 468
 469	spin_unlock_irqrestore(&up->port.lock, flags);
 470}
 471
 472/* port->lock held by caller.  */
 473static void sunsab_stop_rx(struct uart_port *port)
 474{
 475	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 476
 477	up->interrupt_mask0 |= SAB82532_IMR0_TCD;
 478	writeb(up->interrupt_mask1, &up->regs->w.imr0);
 479}
 480
 481/* port->lock held by caller.  */
 482static void sunsab_enable_ms(struct uart_port *port)
 483{
 484	/* For now we always receive these interrupts.  */
 485}
 486
 487/* port->lock is not held.  */
 488static void sunsab_break_ctl(struct uart_port *port, int break_state)
 489{
 490	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 491	unsigned long flags;
 492	unsigned char val;
 493
 494	spin_lock_irqsave(&up->port.lock, flags);
 495
 496	val = up->cached_dafo;
 497	if (break_state)
 498		val |= SAB82532_DAFO_XBRK;
 499	else
 500		val &= ~SAB82532_DAFO_XBRK;
 501	up->cached_dafo = val;
 502
 503	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 504	if (test_bit(SAB82532_XPR, &up->irqflags))
 505		sunsab_tx_idle(up);
 506
 507	spin_unlock_irqrestore(&up->port.lock, flags);
 508}
 509
 510/* port->lock is not held.  */
 511static int sunsab_startup(struct uart_port *port)
 512{
 513	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 514	unsigned long flags;
 515	unsigned char tmp;
 516	int err = request_irq(up->port.irq, sunsab_interrupt,
 517			      IRQF_SHARED, "sab", up);
 518	if (err)
 519		return err;
 520
 521	spin_lock_irqsave(&up->port.lock, flags);
 522
 523	/*
 524	 * Wait for any commands or immediate characters
 525	 */
 526	sunsab_cec_wait(up);
 527	sunsab_tec_wait(up);
 528
 529	/*
 530	 * Clear the FIFO buffers.
 531	 */
 532	writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
 533	sunsab_cec_wait(up);
 534	writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
 535
 536	/*
 537	 * Clear the interrupt registers.
 538	 */
 539	(void) readb(&up->regs->r.isr0);
 540	(void) readb(&up->regs->r.isr1);
 541
 542	/*
 543	 * Now, initialize the UART 
 544	 */
 545	writeb(0, &up->regs->w.ccr0);				/* power-down */
 546	writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
 547	       SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
 548	writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
 549	writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
 550	       SAB82532_CCR2_TOE, &up->regs->w.ccr2);
 551	writeb(0, &up->regs->w.ccr3);
 552	writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
 553	up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
 554			   SAB82532_MODE_RAC);
 555	writeb(up->cached_mode, &up->regs->w.mode);
 556	writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
 557	
 558	tmp = readb(&up->regs->rw.ccr0);
 559	tmp |= SAB82532_CCR0_PU;	/* power-up */
 560	writeb(tmp, &up->regs->rw.ccr0);
 561
 562	/*
 563	 * Finally, enable interrupts
 564	 */
 565	up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 566			       SAB82532_IMR0_PLLA);
 567	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 568	up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 569			       SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 570			       SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 571			       SAB82532_IMR1_XPR);
 572	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 573	set_bit(SAB82532_ALLS, &up->irqflags);
 574	set_bit(SAB82532_XPR, &up->irqflags);
 575
 576	spin_unlock_irqrestore(&up->port.lock, flags);
 577
 578	return 0;
 579}
 580
 581/* port->lock is not held.  */
 582static void sunsab_shutdown(struct uart_port *port)
 583{
 584	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 585	unsigned long flags;
 586
 587	spin_lock_irqsave(&up->port.lock, flags);
 588
 589	/* Disable Interrupts */
 590	up->interrupt_mask0 = 0xff;
 591	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 592	up->interrupt_mask1 = 0xff;
 593	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 594
 595	/* Disable break condition */
 596	up->cached_dafo = readb(&up->regs->rw.dafo);
 597	up->cached_dafo &= ~SAB82532_DAFO_XBRK;
 598	writeb(up->cached_dafo, &up->regs->rw.dafo);
 599
 600	/* Disable Receiver */	
 601	up->cached_mode &= ~SAB82532_MODE_RAC;
 602	writeb(up->cached_mode, &up->regs->rw.mode);
 603
 604	/*
 605	 * XXX FIXME
 606	 *
 607	 * If the chip is powered down here the system hangs/crashes during
 608	 * reboot or shutdown.  This needs to be investigated further,
 609	 * similar behaviour occurs in 2.4 when the driver is configured
 610	 * as a module only.  One hint may be that data is sometimes
 611	 * transmitted at 9600 baud during shutdown (regardless of the
 612	 * speed the chip was configured for when the port was open).
 613	 */
 614#if 0
 615	/* Power Down */	
 616	tmp = readb(&up->regs->rw.ccr0);
 617	tmp &= ~SAB82532_CCR0_PU;
 618	writeb(tmp, &up->regs->rw.ccr0);
 619#endif
 620
 621	spin_unlock_irqrestore(&up->port.lock, flags);
 622	free_irq(up->port.irq, up);
 623}
 624
 625/*
 626 * This is used to figure out the divisor speeds.
 627 *
 628 * The formula is:    Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
 629 *
 630 * with               0 <= N < 64 and 0 <= M < 16
 631 */
 632
 633static void calc_ebrg(int baud, int *n_ret, int *m_ret)
 634{
 635	int	n, m;
 636
 637	if (baud == 0) {
 638		*n_ret = 0;
 639		*m_ret = 0;
 640		return;
 641	}
 642     
 643	/*
 644	 * We scale numbers by 10 so that we get better accuracy
 645	 * without having to use floating point.  Here we increment m
 646	 * until n is within the valid range.
 647	 */
 648	n = (SAB_BASE_BAUD * 10) / baud;
 649	m = 0;
 650	while (n >= 640) {
 651		n = n / 2;
 652		m++;
 653	}
 654	n = (n+5) / 10;
 655	/*
 656	 * We try very hard to avoid speeds with M == 0 since they may
 657	 * not work correctly for XTAL frequences above 10 MHz.
 658	 */
 659	if ((m == 0) && ((n & 1) == 0)) {
 660		n = n / 2;
 661		m++;
 662	}
 663	*n_ret = n - 1;
 664	*m_ret = m;
 665}
 666
 667/* Internal routine, port->lock is held and local interrupts are disabled.  */
 668static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
 669				  unsigned int iflag, unsigned int baud,
 670				  unsigned int quot)
 671{
 672	unsigned char dafo;
 673	int bits, n, m;
 674
 675	/* Byte size and parity */
 676	switch (cflag & CSIZE) {
 677	      case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 678	      case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
 679	      case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
 680	      case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
 681	      /* Never happens, but GCC is too dumb to figure it out */
 682	      default:  dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 683	}
 684
 685	if (cflag & CSTOPB) {
 686		dafo |= SAB82532_DAFO_STOP;
 687		bits++;
 688	}
 689
 690	if (cflag & PARENB) {
 691		dafo |= SAB82532_DAFO_PARE;
 692		bits++;
 693	}
 694
 695	if (cflag & PARODD) {
 696		dafo |= SAB82532_DAFO_PAR_ODD;
 697	} else {
 698		dafo |= SAB82532_DAFO_PAR_EVEN;
 699	}
 700	up->cached_dafo = dafo;
 701
 702	calc_ebrg(baud, &n, &m);
 703
 704	up->cached_ebrg = n | (m << 6);
 705
 706	up->tec_timeout = (10 * 1000000) / baud;
 707	up->cec_timeout = up->tec_timeout >> 2;
 708
 709	/* CTS flow control flags */
 710	/* We encode read_status_mask and ignore_status_mask like so:
 711	 *
 712	 * ---------------------
 713	 * | ... | ISR1 | ISR0 |
 714	 * ---------------------
 715	 *  ..    15   8 7    0
 716	 */
 717
 718	up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 719				     SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
 720				     SAB82532_ISR0_CDSC);
 721	up->port.read_status_mask |= (SAB82532_ISR1_CSC |
 722				      SAB82532_ISR1_ALLS |
 723				      SAB82532_ISR1_XPR) << 8;
 724	if (iflag & INPCK)
 725		up->port.read_status_mask |= (SAB82532_ISR0_PERR |
 726					      SAB82532_ISR0_FERR);
 727	if (iflag & (BRKINT | PARMRK))
 728		up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
 729
 730	/*
 731	 * Characteres to ignore
 732	 */
 733	up->port.ignore_status_mask = 0;
 734	if (iflag & IGNPAR)
 735		up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
 736						SAB82532_ISR0_FERR);
 737	if (iflag & IGNBRK) {
 738		up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
 739		/*
 740		 * If we're ignoring parity and break indicators,
 741		 * ignore overruns too (for real raw support).
 742		 */
 743		if (iflag & IGNPAR)
 744			up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
 745	}
 746
 747	/*
 748	 * ignore all characters if CREAD is not set
 749	 */
 750	if ((cflag & CREAD) == 0)
 751		up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
 752						SAB82532_ISR0_TCD);
 753
 754	uart_update_timeout(&up->port, cflag,
 755			    (up->port.uartclk / (16 * quot)));
 756
 757	/* Now schedule a register update when the chip's
 758	 * transmitter is idle.
 759	 */
 760	up->cached_mode |= SAB82532_MODE_RAC;
 761	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 762	if (test_bit(SAB82532_XPR, &up->irqflags))
 763		sunsab_tx_idle(up);
 764}
 765
 766/* port->lock is not held.  */
 767static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
 768			       struct ktermios *old)
 769{
 770	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 771	unsigned long flags;
 772	unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
 773	unsigned int quot = uart_get_divisor(port, baud);
 774
 775	spin_lock_irqsave(&up->port.lock, flags);
 776	sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
 777	spin_unlock_irqrestore(&up->port.lock, flags);
 778}
 779
 780static const char *sunsab_type(struct uart_port *port)
 781{
 782	struct uart_sunsab_port *up = (void *)port;
 783	static char buf[36];
 784	
 785	sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
 786	return buf;
 787}
 788
 789static void sunsab_release_port(struct uart_port *port)
 790{
 791}
 792
 793static int sunsab_request_port(struct uart_port *port)
 794{
 795	return 0;
 796}
 797
 798static void sunsab_config_port(struct uart_port *port, int flags)
 799{
 800}
 801
 802static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
 803{
 804	return -EINVAL;
 805}
 806
 807static struct uart_ops sunsab_pops = {
 808	.tx_empty	= sunsab_tx_empty,
 809	.set_mctrl	= sunsab_set_mctrl,
 810	.get_mctrl	= sunsab_get_mctrl,
 811	.stop_tx	= sunsab_stop_tx,
 812	.start_tx	= sunsab_start_tx,
 813	.send_xchar	= sunsab_send_xchar,
 814	.stop_rx	= sunsab_stop_rx,
 815	.enable_ms	= sunsab_enable_ms,
 816	.break_ctl	= sunsab_break_ctl,
 817	.startup	= sunsab_startup,
 818	.shutdown	= sunsab_shutdown,
 819	.set_termios	= sunsab_set_termios,
 820	.type		= sunsab_type,
 821	.release_port	= sunsab_release_port,
 822	.request_port	= sunsab_request_port,
 823	.config_port	= sunsab_config_port,
 824	.verify_port	= sunsab_verify_port,
 825};
 826
 827static struct uart_driver sunsab_reg = {
 828	.owner			= THIS_MODULE,
 829	.driver_name		= "sunsab",
 830	.dev_name		= "ttyS",
 831	.major			= TTY_MAJOR,
 832};
 833
 834static struct uart_sunsab_port *sunsab_ports;
 835
 836#ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
 837
 838static void sunsab_console_putchar(struct uart_port *port, int c)
 839{
 840	struct uart_sunsab_port *up = (struct uart_sunsab_port *)port;
 841
 842	sunsab_tec_wait(up);
 843	writeb(c, &up->regs->w.tic);
 844}
 845
 846static void sunsab_console_write(struct console *con, const char *s, unsigned n)
 847{
 848	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 849	unsigned long flags;
 850	int locked = 1;
 851
 852	local_irq_save(flags);
 853	if (up->port.sysrq) {
 854		locked = 0;
 855	} else if (oops_in_progress) {
 856		locked = spin_trylock(&up->port.lock);
 857	} else
 858		spin_lock(&up->port.lock);
 859
 860	uart_console_write(&up->port, s, n, sunsab_console_putchar);
 861	sunsab_tec_wait(up);
 862
 863	if (locked)
 864		spin_unlock(&up->port.lock);
 865	local_irq_restore(flags);
 866}
 867
 868static int sunsab_console_setup(struct console *con, char *options)
 869{
 870	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 871	unsigned long flags;
 872	unsigned int baud, quot;
 873
 874	/*
 875	 * The console framework calls us for each and every port
 876	 * registered. Defer the console setup until the requested
 877	 * port has been properly discovered. A bit of a hack,
 878	 * though...
 879	 */
 880	if (up->port.type != PORT_SUNSAB)
 881		return -1;
 882
 883	printk("Console: ttyS%d (SAB82532)\n",
 884	       (sunsab_reg.minor - 64) + con->index);
 885
 886	sunserial_console_termios(con, up->port.dev->of_node);
 887
 888	switch (con->cflag & CBAUD) {
 889	case B150: baud = 150; break;
 890	case B300: baud = 300; break;
 891	case B600: baud = 600; break;
 892	case B1200: baud = 1200; break;
 893	case B2400: baud = 2400; break;
 894	case B4800: baud = 4800; break;
 895	default: case B9600: baud = 9600; break;
 896	case B19200: baud = 19200; break;
 897	case B38400: baud = 38400; break;
 898	case B57600: baud = 57600; break;
 899	case B115200: baud = 115200; break;
 900	case B230400: baud = 230400; break;
 901	case B460800: baud = 460800; break;
 902	};
 903
 904	/*
 905	 * Temporary fix.
 906	 */
 907	spin_lock_init(&up->port.lock);
 908
 909	/*
 910	 * Initialize the hardware
 911	 */
 912	sunsab_startup(&up->port);
 913
 914	spin_lock_irqsave(&up->port.lock, flags);
 915
 916	/*
 917	 * Finally, enable interrupts
 918	 */
 919	up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 920				SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
 921	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 922	up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 923				SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 924				SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 925				SAB82532_IMR1_XPR;
 926	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 927
 928	quot = uart_get_divisor(&up->port, baud);
 929	sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
 930	sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
 931
 932	spin_unlock_irqrestore(&up->port.lock, flags);
 933	
 934	return 0;
 935}
 936
 937static struct console sunsab_console = {
 938	.name	=	"ttyS",
 939	.write	=	sunsab_console_write,
 940	.device	=	uart_console_device,
 941	.setup	=	sunsab_console_setup,
 942	.flags	=	CON_PRINTBUFFER,
 943	.index	=	-1,
 944	.data	=	&sunsab_reg,
 945};
 946
 947static inline struct console *SUNSAB_CONSOLE(void)
 948{
 949	return &sunsab_console;
 950}
 951#else
 952#define SUNSAB_CONSOLE()	(NULL)
 953#define sunsab_console_init()	do { } while (0)
 954#endif
 955
 956static int __devinit sunsab_init_one(struct uart_sunsab_port *up,
 957				     struct platform_device *op,
 958				     unsigned long offset,
 959				     int line)
 960{
 961	up->port.line = line;
 962	up->port.dev = &op->dev;
 963
 964	up->port.mapbase = op->resource[0].start + offset;
 965	up->port.membase = of_ioremap(&op->resource[0], offset,
 966				      sizeof(union sab82532_async_regs),
 967				      "sab");
 968	if (!up->port.membase)
 969		return -ENOMEM;
 970	up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
 971
 972	up->port.irq = op->archdata.irqs[0];
 973
 974	up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
 975	up->port.iotype = UPIO_MEM;
 976
 977	writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
 978
 979	up->port.ops = &sunsab_pops;
 980	up->port.type = PORT_SUNSAB;
 981	up->port.uartclk = SAB_BASE_BAUD;
 982
 983	up->type = readb(&up->regs->r.vstr) & 0x0f;
 984	writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
 985	writeb(0xff, &up->regs->w.pim);
 986	if ((up->port.line & 0x1) == 0) {
 987		up->pvr_dsr_bit = (1 << 0);
 988		up->pvr_dtr_bit = (1 << 1);
 989		up->gis_shift = 2;
 990	} else {
 991		up->pvr_dsr_bit = (1 << 3);
 992		up->pvr_dtr_bit = (1 << 2);
 993		up->gis_shift = 0;
 994	}
 995	up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
 996	writeb(up->cached_pvr, &up->regs->w.pvr);
 997	up->cached_mode = readb(&up->regs->rw.mode);
 998	up->cached_mode |= SAB82532_MODE_FRTS;
 999	writeb(up->cached_mode, &up->regs->rw.mode);
1000	up->cached_mode |= SAB82532_MODE_RTS;
1001	writeb(up->cached_mode, &up->regs->rw.mode);
1002
1003	up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
1004	up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
1005
1006	return 0;
1007}
1008
1009static int __devinit sab_probe(struct platform_device *op)
1010{
1011	static int inst;
1012	struct uart_sunsab_port *up;
1013	int err;
1014
1015	up = &sunsab_ports[inst * 2];
1016
1017	err = sunsab_init_one(&up[0], op,
1018			      0,
1019			      (inst * 2) + 0);
1020	if (err)
1021		goto out;
1022
1023	err = sunsab_init_one(&up[1], op,
1024			      sizeof(union sab82532_async_regs),
1025			      (inst * 2) + 1);
1026	if (err)
1027		goto out1;
1028
1029	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1030				&sunsab_reg, up[0].port.line,
1031				false);
1032
1033	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1034				&sunsab_reg, up[1].port.line,
1035				false);
1036
1037	err = uart_add_one_port(&sunsab_reg, &up[0].port);
1038	if (err)
1039		goto out2;
1040
1041	err = uart_add_one_port(&sunsab_reg, &up[1].port);
1042	if (err)
1043		goto out3;
1044
1045	dev_set_drvdata(&op->dev, &up[0]);
1046
1047	inst++;
1048
1049	return 0;
1050
1051out3:
1052	uart_remove_one_port(&sunsab_reg, &up[0].port);
1053out2:
1054	of_iounmap(&op->resource[0],
1055		   up[1].port.membase,
1056		   sizeof(union sab82532_async_regs));
1057out1:
1058	of_iounmap(&op->resource[0],
1059		   up[0].port.membase,
1060		   sizeof(union sab82532_async_regs));
1061out:
1062	return err;
1063}
1064
1065static int __devexit sab_remove(struct platform_device *op)
1066{
1067	struct uart_sunsab_port *up = dev_get_drvdata(&op->dev);
1068
1069	uart_remove_one_port(&sunsab_reg, &up[1].port);
1070	uart_remove_one_port(&sunsab_reg, &up[0].port);
1071	of_iounmap(&op->resource[0],
1072		   up[1].port.membase,
1073		   sizeof(union sab82532_async_regs));
1074	of_iounmap(&op->resource[0],
1075		   up[0].port.membase,
1076		   sizeof(union sab82532_async_regs));
1077
1078	dev_set_drvdata(&op->dev, NULL);
1079
1080	return 0;
1081}
1082
1083static const struct of_device_id sab_match[] = {
1084	{
1085		.name = "se",
1086	},
1087	{
1088		.name = "serial",
1089		.compatible = "sab82532",
1090	},
1091	{},
1092};
1093MODULE_DEVICE_TABLE(of, sab_match);
1094
1095static struct platform_driver sab_driver = {
1096	.driver = {
1097		.name = "sab",
1098		.owner = THIS_MODULE,
1099		.of_match_table = sab_match,
1100	},
1101	.probe		= sab_probe,
1102	.remove		= __devexit_p(sab_remove),
1103};
1104
1105static int __init sunsab_init(void)
1106{
1107	struct device_node *dp;
1108	int err;
1109	int num_channels = 0;
1110
1111	for_each_node_by_name(dp, "se")
1112		num_channels += 2;
1113	for_each_node_by_name(dp, "serial") {
1114		if (of_device_is_compatible(dp, "sab82532"))
1115			num_channels += 2;
1116	}
1117
1118	if (num_channels) {
1119		sunsab_ports = kzalloc(sizeof(struct uart_sunsab_port) *
1120				       num_channels, GFP_KERNEL);
1121		if (!sunsab_ports)
1122			return -ENOMEM;
1123
1124		err = sunserial_register_minors(&sunsab_reg, num_channels);
1125		if (err) {
1126			kfree(sunsab_ports);
1127			sunsab_ports = NULL;
1128
1129			return err;
1130		}
1131	}
1132
1133	return platform_driver_register(&sab_driver);
1134}
1135
1136static void __exit sunsab_exit(void)
1137{
1138	platform_driver_unregister(&sab_driver);
1139	if (sunsab_reg.nr) {
1140		sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
1141	}
1142
1143	kfree(sunsab_ports);
1144	sunsab_ports = NULL;
1145}
1146
1147module_init(sunsab_init);
1148module_exit(sunsab_exit);
1149
1150MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1151MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1152MODULE_LICENSE("GPL");
v3.5.6
   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_struct *
 111receive_chars(struct uart_sunsab_port *up,
 112	      union sab82532_irq_status *stat)
 113{
 114	struct tty_struct *tty = 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		tty = up->port.state->port.tty;
 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 tty;
 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		if (tty == NULL) {
 164			uart_handle_sysrq_char(&up->port, ch);
 165			continue;
 166		}
 167
 168		flag = TTY_NORMAL;
 169		up->port.icount.rx++;
 170
 171		if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
 172						SAB82532_ISR0_FERR |
 173						SAB82532_ISR0_RFO)) ||
 174		    unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 175			/*
 176			 * For statistics only
 177			 */
 178			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 179				stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 180						     SAB82532_ISR0_FERR);
 181				up->port.icount.brk++;
 182				/*
 183				 * We do the SysRQ and SAK checking
 184				 * here because otherwise the break
 185				 * may get masked by ignore_status_mask
 186				 * or read_status_mask.
 187				 */
 188				if (uart_handle_break(&up->port))
 189					continue;
 190			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 191				up->port.icount.parity++;
 192			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 193				up->port.icount.frame++;
 194			if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 195				up->port.icount.overrun++;
 196
 197			/*
 198			 * Mask off conditions which should be ingored.
 199			 */
 200			stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
 201			stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
 202
 203			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 204				flag = TTY_BREAK;
 205			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 206				flag = TTY_PARITY;
 207			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 208				flag = TTY_FRAME;
 209		}
 210
 211		if (uart_handle_sysrq_char(&up->port, ch))
 212			continue;
 213
 214		if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
 215		    (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
 216			tty_insert_flip_char(tty, ch, flag);
 217		if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 218			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
 219	}
 220
 221	if (saw_console_brk)
 222		sun_do_break();
 223
 224	return tty;
 225}
 226
 227static void sunsab_stop_tx(struct uart_port *);
 228static void sunsab_tx_idle(struct uart_sunsab_port *);
 229
 230static void transmit_chars(struct uart_sunsab_port *up,
 231			   union sab82532_irq_status *stat)
 232{
 233	struct circ_buf *xmit = &up->port.state->xmit;
 234	int i;
 235
 236	if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
 237		up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
 238		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 239		set_bit(SAB82532_ALLS, &up->irqflags);
 240	}
 241
 242#if 0 /* bde@nwlink.com says this check causes problems */
 243	if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
 244		return;
 245#endif
 246
 247	if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
 248		return;
 249
 250	set_bit(SAB82532_XPR, &up->irqflags);
 251	sunsab_tx_idle(up);
 252
 253	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 254		up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 255		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 256		return;
 257	}
 258
 259	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 260	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 261	clear_bit(SAB82532_ALLS, &up->irqflags);
 262
 263	/* Stuff 32 bytes into Transmit FIFO. */
 264	clear_bit(SAB82532_XPR, &up->irqflags);
 265	for (i = 0; i < up->port.fifosize; i++) {
 266		writeb(xmit->buf[xmit->tail],
 267		       &up->regs->w.xfifo[i]);
 268		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 269		up->port.icount.tx++;
 270		if (uart_circ_empty(xmit))
 271			break;
 272	}
 273
 274	/* Issue a Transmit Frame command. */
 275	sunsab_cec_wait(up);
 276	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 277
 278	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 279		uart_write_wakeup(&up->port);
 280
 281	if (uart_circ_empty(xmit))
 282		sunsab_stop_tx(&up->port);
 283}
 284
 285static void check_status(struct uart_sunsab_port *up,
 286			 union sab82532_irq_status *stat)
 287{
 288	if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
 289		uart_handle_dcd_change(&up->port,
 290				       !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
 291
 292	if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
 293		uart_handle_cts_change(&up->port,
 294				       (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
 295
 296	if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
 297		up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
 298		up->port.icount.dsr++;
 299	}
 300
 301	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 302}
 303
 304static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
 305{
 306	struct uart_sunsab_port *up = dev_id;
 307	struct tty_struct *tty;
 308	union sab82532_irq_status status;
 309	unsigned long flags;
 310	unsigned char gis;
 311
 312	spin_lock_irqsave(&up->port.lock, flags);
 313
 314	status.stat = 0;
 315	gis = readb(&up->regs->r.gis) >> up->gis_shift;
 316	if (gis & 1)
 317		status.sreg.isr0 = readb(&up->regs->r.isr0);
 318	if (gis & 2)
 319		status.sreg.isr1 = readb(&up->regs->r.isr1);
 320
 321	tty = NULL;
 322	if (status.stat) {
 323		if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 324					 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
 325		    (status.sreg.isr1 & SAB82532_ISR1_BRK))
 326			tty = receive_chars(up, &status);
 327		if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
 328		    (status.sreg.isr1 & SAB82532_ISR1_CSC))
 329			check_status(up, &status);
 330		if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
 331			transmit_chars(up, &status);
 332	}
 333
 334	spin_unlock_irqrestore(&up->port.lock, flags);
 335
 336	if (tty)
 337		tty_flip_buffer_push(tty);
 338
 339	return IRQ_HANDLED;
 340}
 341
 342/* port->lock is not held.  */
 343static unsigned int sunsab_tx_empty(struct uart_port *port)
 344{
 345	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 346	int ret;
 347
 348	/* Do not need a lock for a state test like this.  */
 349	if (test_bit(SAB82532_ALLS, &up->irqflags))
 350		ret = TIOCSER_TEMT;
 351	else
 352		ret = 0;
 353
 354	return ret;
 355}
 356
 357/* port->lock held by caller.  */
 358static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
 359{
 360	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 361
 362	if (mctrl & TIOCM_RTS) {
 363		up->cached_mode &= ~SAB82532_MODE_FRTS;
 364		up->cached_mode |= SAB82532_MODE_RTS;
 365	} else {
 366		up->cached_mode |= (SAB82532_MODE_FRTS |
 367				    SAB82532_MODE_RTS);
 368	}
 369	if (mctrl & TIOCM_DTR) {
 370		up->cached_pvr &= ~(up->pvr_dtr_bit);
 371	} else {
 372		up->cached_pvr |= up->pvr_dtr_bit;
 373	}
 374
 375	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 376	if (test_bit(SAB82532_XPR, &up->irqflags))
 377		sunsab_tx_idle(up);
 378}
 379
 380/* port->lock is held by caller and interrupts are disabled.  */
 381static unsigned int sunsab_get_mctrl(struct uart_port *port)
 382{
 383	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 384	unsigned char val;
 385	unsigned int result;
 386
 387	result = 0;
 388
 389	val = readb(&up->regs->r.pvr);
 390	result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
 391
 392	val = readb(&up->regs->r.vstr);
 393	result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
 394
 395	val = readb(&up->regs->r.star);
 396	result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
 397
 398	return result;
 399}
 400
 401/* port->lock held by caller.  */
 402static void sunsab_stop_tx(struct uart_port *port)
 403{
 404	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 405
 406	up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 407	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 408}
 409
 410/* port->lock held by caller.  */
 411static void sunsab_tx_idle(struct uart_sunsab_port *up)
 412{
 413	if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
 414		u8 tmp;
 415
 416		clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
 417		writeb(up->cached_mode, &up->regs->rw.mode);
 418		writeb(up->cached_pvr, &up->regs->rw.pvr);
 419		writeb(up->cached_dafo, &up->regs->w.dafo);
 420
 421		writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
 422		tmp = readb(&up->regs->rw.ccr2);
 423		tmp &= ~0xc0;
 424		tmp |= (up->cached_ebrg >> 2) & 0xc0;
 425		writeb(tmp, &up->regs->rw.ccr2);
 426	}
 427}
 428
 429/* port->lock held by caller.  */
 430static void sunsab_start_tx(struct uart_port *port)
 431{
 432	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 433	struct circ_buf *xmit = &up->port.state->xmit;
 434	int i;
 435
 436	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 437	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 438	
 439	if (!test_bit(SAB82532_XPR, &up->irqflags))
 440		return;
 441
 442	clear_bit(SAB82532_ALLS, &up->irqflags);
 443	clear_bit(SAB82532_XPR, &up->irqflags);
 444
 445	for (i = 0; i < up->port.fifosize; i++) {
 446		writeb(xmit->buf[xmit->tail],
 447		       &up->regs->w.xfifo[i]);
 448		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 449		up->port.icount.tx++;
 450		if (uart_circ_empty(xmit))
 451			break;
 452	}
 453
 454	/* Issue a Transmit Frame command.  */
 455	sunsab_cec_wait(up);
 456	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 457}
 458
 459/* port->lock is not held.  */
 460static void sunsab_send_xchar(struct uart_port *port, char ch)
 461{
 462	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 463	unsigned long flags;
 464
 465	spin_lock_irqsave(&up->port.lock, flags);
 466
 467	sunsab_tec_wait(up);
 468	writeb(ch, &up->regs->w.tic);
 469
 470	spin_unlock_irqrestore(&up->port.lock, flags);
 471}
 472
 473/* port->lock held by caller.  */
 474static void sunsab_stop_rx(struct uart_port *port)
 475{
 476	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 477
 478	up->interrupt_mask0 |= SAB82532_IMR0_TCD;
 479	writeb(up->interrupt_mask1, &up->regs->w.imr0);
 480}
 481
 482/* port->lock held by caller.  */
 483static void sunsab_enable_ms(struct uart_port *port)
 484{
 485	/* For now we always receive these interrupts.  */
 486}
 487
 488/* port->lock is not held.  */
 489static void sunsab_break_ctl(struct uart_port *port, int break_state)
 490{
 491	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 492	unsigned long flags;
 493	unsigned char val;
 494
 495	spin_lock_irqsave(&up->port.lock, flags);
 496
 497	val = up->cached_dafo;
 498	if (break_state)
 499		val |= SAB82532_DAFO_XBRK;
 500	else
 501		val &= ~SAB82532_DAFO_XBRK;
 502	up->cached_dafo = val;
 503
 504	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 505	if (test_bit(SAB82532_XPR, &up->irqflags))
 506		sunsab_tx_idle(up);
 507
 508	spin_unlock_irqrestore(&up->port.lock, flags);
 509}
 510
 511/* port->lock is not held.  */
 512static int sunsab_startup(struct uart_port *port)
 513{
 514	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 515	unsigned long flags;
 516	unsigned char tmp;
 517	int err = request_irq(up->port.irq, sunsab_interrupt,
 518			      IRQF_SHARED, "sab", up);
 519	if (err)
 520		return err;
 521
 522	spin_lock_irqsave(&up->port.lock, flags);
 523
 524	/*
 525	 * Wait for any commands or immediate characters
 526	 */
 527	sunsab_cec_wait(up);
 528	sunsab_tec_wait(up);
 529
 530	/*
 531	 * Clear the FIFO buffers.
 532	 */
 533	writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
 534	sunsab_cec_wait(up);
 535	writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
 536
 537	/*
 538	 * Clear the interrupt registers.
 539	 */
 540	(void) readb(&up->regs->r.isr0);
 541	(void) readb(&up->regs->r.isr1);
 542
 543	/*
 544	 * Now, initialize the UART 
 545	 */
 546	writeb(0, &up->regs->w.ccr0);				/* power-down */
 547	writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
 548	       SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
 549	writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
 550	writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
 551	       SAB82532_CCR2_TOE, &up->regs->w.ccr2);
 552	writeb(0, &up->regs->w.ccr3);
 553	writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
 554	up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
 555			   SAB82532_MODE_RAC);
 556	writeb(up->cached_mode, &up->regs->w.mode);
 557	writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
 558	
 559	tmp = readb(&up->regs->rw.ccr0);
 560	tmp |= SAB82532_CCR0_PU;	/* power-up */
 561	writeb(tmp, &up->regs->rw.ccr0);
 562
 563	/*
 564	 * Finally, enable interrupts
 565	 */
 566	up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 567			       SAB82532_IMR0_PLLA);
 568	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 569	up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 570			       SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 571			       SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 572			       SAB82532_IMR1_XPR);
 573	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 574	set_bit(SAB82532_ALLS, &up->irqflags);
 575	set_bit(SAB82532_XPR, &up->irqflags);
 576
 577	spin_unlock_irqrestore(&up->port.lock, flags);
 578
 579	return 0;
 580}
 581
 582/* port->lock is not held.  */
 583static void sunsab_shutdown(struct uart_port *port)
 584{
 585	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 586	unsigned long flags;
 587
 588	spin_lock_irqsave(&up->port.lock, flags);
 589
 590	/* Disable Interrupts */
 591	up->interrupt_mask0 = 0xff;
 592	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 593	up->interrupt_mask1 = 0xff;
 594	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 595
 596	/* Disable break condition */
 597	up->cached_dafo = readb(&up->regs->rw.dafo);
 598	up->cached_dafo &= ~SAB82532_DAFO_XBRK;
 599	writeb(up->cached_dafo, &up->regs->rw.dafo);
 600
 601	/* Disable Receiver */	
 602	up->cached_mode &= ~SAB82532_MODE_RAC;
 603	writeb(up->cached_mode, &up->regs->rw.mode);
 604
 605	/*
 606	 * XXX FIXME
 607	 *
 608	 * If the chip is powered down here the system hangs/crashes during
 609	 * reboot or shutdown.  This needs to be investigated further,
 610	 * similar behaviour occurs in 2.4 when the driver is configured
 611	 * as a module only.  One hint may be that data is sometimes
 612	 * transmitted at 9600 baud during shutdown (regardless of the
 613	 * speed the chip was configured for when the port was open).
 614	 */
 615#if 0
 616	/* Power Down */	
 617	tmp = readb(&up->regs->rw.ccr0);
 618	tmp &= ~SAB82532_CCR0_PU;
 619	writeb(tmp, &up->regs->rw.ccr0);
 620#endif
 621
 622	spin_unlock_irqrestore(&up->port.lock, flags);
 623	free_irq(up->port.irq, up);
 624}
 625
 626/*
 627 * This is used to figure out the divisor speeds.
 628 *
 629 * The formula is:    Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
 630 *
 631 * with               0 <= N < 64 and 0 <= M < 16
 632 */
 633
 634static void calc_ebrg(int baud, int *n_ret, int *m_ret)
 635{
 636	int	n, m;
 637
 638	if (baud == 0) {
 639		*n_ret = 0;
 640		*m_ret = 0;
 641		return;
 642	}
 643     
 644	/*
 645	 * We scale numbers by 10 so that we get better accuracy
 646	 * without having to use floating point.  Here we increment m
 647	 * until n is within the valid range.
 648	 */
 649	n = (SAB_BASE_BAUD * 10) / baud;
 650	m = 0;
 651	while (n >= 640) {
 652		n = n / 2;
 653		m++;
 654	}
 655	n = (n+5) / 10;
 656	/*
 657	 * We try very hard to avoid speeds with M == 0 since they may
 658	 * not work correctly for XTAL frequences above 10 MHz.
 659	 */
 660	if ((m == 0) && ((n & 1) == 0)) {
 661		n = n / 2;
 662		m++;
 663	}
 664	*n_ret = n - 1;
 665	*m_ret = m;
 666}
 667
 668/* Internal routine, port->lock is held and local interrupts are disabled.  */
 669static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
 670				  unsigned int iflag, unsigned int baud,
 671				  unsigned int quot)
 672{
 673	unsigned char dafo;
 674	int bits, n, m;
 675
 676	/* Byte size and parity */
 677	switch (cflag & CSIZE) {
 678	      case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 679	      case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
 680	      case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
 681	      case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
 682	      /* Never happens, but GCC is too dumb to figure it out */
 683	      default:  dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 684	}
 685
 686	if (cflag & CSTOPB) {
 687		dafo |= SAB82532_DAFO_STOP;
 688		bits++;
 689	}
 690
 691	if (cflag & PARENB) {
 692		dafo |= SAB82532_DAFO_PARE;
 693		bits++;
 694	}
 695
 696	if (cflag & PARODD) {
 697		dafo |= SAB82532_DAFO_PAR_ODD;
 698	} else {
 699		dafo |= SAB82532_DAFO_PAR_EVEN;
 700	}
 701	up->cached_dafo = dafo;
 702
 703	calc_ebrg(baud, &n, &m);
 704
 705	up->cached_ebrg = n | (m << 6);
 706
 707	up->tec_timeout = (10 * 1000000) / baud;
 708	up->cec_timeout = up->tec_timeout >> 2;
 709
 710	/* CTS flow control flags */
 711	/* We encode read_status_mask and ignore_status_mask like so:
 712	 *
 713	 * ---------------------
 714	 * | ... | ISR1 | ISR0 |
 715	 * ---------------------
 716	 *  ..    15   8 7    0
 717	 */
 718
 719	up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 720				     SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
 721				     SAB82532_ISR0_CDSC);
 722	up->port.read_status_mask |= (SAB82532_ISR1_CSC |
 723				      SAB82532_ISR1_ALLS |
 724				      SAB82532_ISR1_XPR) << 8;
 725	if (iflag & INPCK)
 726		up->port.read_status_mask |= (SAB82532_ISR0_PERR |
 727					      SAB82532_ISR0_FERR);
 728	if (iflag & (BRKINT | PARMRK))
 729		up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
 730
 731	/*
 732	 * Characteres to ignore
 733	 */
 734	up->port.ignore_status_mask = 0;
 735	if (iflag & IGNPAR)
 736		up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
 737						SAB82532_ISR0_FERR);
 738	if (iflag & IGNBRK) {
 739		up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
 740		/*
 741		 * If we're ignoring parity and break indicators,
 742		 * ignore overruns too (for real raw support).
 743		 */
 744		if (iflag & IGNPAR)
 745			up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
 746	}
 747
 748	/*
 749	 * ignore all characters if CREAD is not set
 750	 */
 751	if ((cflag & CREAD) == 0)
 752		up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
 753						SAB82532_ISR0_TCD);
 754
 755	uart_update_timeout(&up->port, cflag,
 756			    (up->port.uartclk / (16 * quot)));
 757
 758	/* Now schedule a register update when the chip's
 759	 * transmitter is idle.
 760	 */
 761	up->cached_mode |= SAB82532_MODE_RAC;
 762	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 763	if (test_bit(SAB82532_XPR, &up->irqflags))
 764		sunsab_tx_idle(up);
 765}
 766
 767/* port->lock is not held.  */
 768static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
 769			       struct ktermios *old)
 770{
 771	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 772	unsigned long flags;
 773	unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
 774	unsigned int quot = uart_get_divisor(port, baud);
 775
 776	spin_lock_irqsave(&up->port.lock, flags);
 777	sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
 778	spin_unlock_irqrestore(&up->port.lock, flags);
 779}
 780
 781static const char *sunsab_type(struct uart_port *port)
 782{
 783	struct uart_sunsab_port *up = (void *)port;
 784	static char buf[36];
 785	
 786	sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
 787	return buf;
 788}
 789
 790static void sunsab_release_port(struct uart_port *port)
 791{
 792}
 793
 794static int sunsab_request_port(struct uart_port *port)
 795{
 796	return 0;
 797}
 798
 799static void sunsab_config_port(struct uart_port *port, int flags)
 800{
 801}
 802
 803static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
 804{
 805	return -EINVAL;
 806}
 807
 808static struct uart_ops sunsab_pops = {
 809	.tx_empty	= sunsab_tx_empty,
 810	.set_mctrl	= sunsab_set_mctrl,
 811	.get_mctrl	= sunsab_get_mctrl,
 812	.stop_tx	= sunsab_stop_tx,
 813	.start_tx	= sunsab_start_tx,
 814	.send_xchar	= sunsab_send_xchar,
 815	.stop_rx	= sunsab_stop_rx,
 816	.enable_ms	= sunsab_enable_ms,
 817	.break_ctl	= sunsab_break_ctl,
 818	.startup	= sunsab_startup,
 819	.shutdown	= sunsab_shutdown,
 820	.set_termios	= sunsab_set_termios,
 821	.type		= sunsab_type,
 822	.release_port	= sunsab_release_port,
 823	.request_port	= sunsab_request_port,
 824	.config_port	= sunsab_config_port,
 825	.verify_port	= sunsab_verify_port,
 826};
 827
 828static struct uart_driver sunsab_reg = {
 829	.owner			= THIS_MODULE,
 830	.driver_name		= "sunsab",
 831	.dev_name		= "ttyS",
 832	.major			= TTY_MAJOR,
 833};
 834
 835static struct uart_sunsab_port *sunsab_ports;
 836
 837#ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
 838
 839static void sunsab_console_putchar(struct uart_port *port, int c)
 840{
 841	struct uart_sunsab_port *up = (struct uart_sunsab_port *)port;
 842
 843	sunsab_tec_wait(up);
 844	writeb(c, &up->regs->w.tic);
 845}
 846
 847static void sunsab_console_write(struct console *con, const char *s, unsigned n)
 848{
 849	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 850	unsigned long flags;
 851	int locked = 1;
 852
 853	local_irq_save(flags);
 854	if (up->port.sysrq) {
 855		locked = 0;
 856	} else if (oops_in_progress) {
 857		locked = spin_trylock(&up->port.lock);
 858	} else
 859		spin_lock(&up->port.lock);
 860
 861	uart_console_write(&up->port, s, n, sunsab_console_putchar);
 862	sunsab_tec_wait(up);
 863
 864	if (locked)
 865		spin_unlock(&up->port.lock);
 866	local_irq_restore(flags);
 867}
 868
 869static int sunsab_console_setup(struct console *con, char *options)
 870{
 871	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 872	unsigned long flags;
 873	unsigned int baud, quot;
 874
 875	/*
 876	 * The console framework calls us for each and every port
 877	 * registered. Defer the console setup until the requested
 878	 * port has been properly discovered. A bit of a hack,
 879	 * though...
 880	 */
 881	if (up->port.type != PORT_SUNSAB)
 882		return -1;
 883
 884	printk("Console: ttyS%d (SAB82532)\n",
 885	       (sunsab_reg.minor - 64) + con->index);
 886
 887	sunserial_console_termios(con, up->port.dev->of_node);
 888
 889	switch (con->cflag & CBAUD) {
 890	case B150: baud = 150; break;
 891	case B300: baud = 300; break;
 892	case B600: baud = 600; break;
 893	case B1200: baud = 1200; break;
 894	case B2400: baud = 2400; break;
 895	case B4800: baud = 4800; break;
 896	default: case B9600: baud = 9600; break;
 897	case B19200: baud = 19200; break;
 898	case B38400: baud = 38400; break;
 899	case B57600: baud = 57600; break;
 900	case B115200: baud = 115200; break;
 901	case B230400: baud = 230400; break;
 902	case B460800: baud = 460800; break;
 903	};
 904
 905	/*
 906	 * Temporary fix.
 907	 */
 908	spin_lock_init(&up->port.lock);
 909
 910	/*
 911	 * Initialize the hardware
 912	 */
 913	sunsab_startup(&up->port);
 914
 915	spin_lock_irqsave(&up->port.lock, flags);
 916
 917	/*
 918	 * Finally, enable interrupts
 919	 */
 920	up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 921				SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
 922	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 923	up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 924				SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 925				SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 926				SAB82532_IMR1_XPR;
 927	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 928
 929	quot = uart_get_divisor(&up->port, baud);
 930	sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
 931	sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
 932
 933	spin_unlock_irqrestore(&up->port.lock, flags);
 934	
 935	return 0;
 936}
 937
 938static struct console sunsab_console = {
 939	.name	=	"ttyS",
 940	.write	=	sunsab_console_write,
 941	.device	=	uart_console_device,
 942	.setup	=	sunsab_console_setup,
 943	.flags	=	CON_PRINTBUFFER,
 944	.index	=	-1,
 945	.data	=	&sunsab_reg,
 946};
 947
 948static inline struct console *SUNSAB_CONSOLE(void)
 949{
 950	return &sunsab_console;
 951}
 952#else
 953#define SUNSAB_CONSOLE()	(NULL)
 954#define sunsab_console_init()	do { } while (0)
 955#endif
 956
 957static int __devinit sunsab_init_one(struct uart_sunsab_port *up,
 958				     struct platform_device *op,
 959				     unsigned long offset,
 960				     int line)
 961{
 962	up->port.line = line;
 963	up->port.dev = &op->dev;
 964
 965	up->port.mapbase = op->resource[0].start + offset;
 966	up->port.membase = of_ioremap(&op->resource[0], offset,
 967				      sizeof(union sab82532_async_regs),
 968				      "sab");
 969	if (!up->port.membase)
 970		return -ENOMEM;
 971	up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
 972
 973	up->port.irq = op->archdata.irqs[0];
 974
 975	up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
 976	up->port.iotype = UPIO_MEM;
 977
 978	writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
 979
 980	up->port.ops = &sunsab_pops;
 981	up->port.type = PORT_SUNSAB;
 982	up->port.uartclk = SAB_BASE_BAUD;
 983
 984	up->type = readb(&up->regs->r.vstr) & 0x0f;
 985	writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
 986	writeb(0xff, &up->regs->w.pim);
 987	if ((up->port.line & 0x1) == 0) {
 988		up->pvr_dsr_bit = (1 << 0);
 989		up->pvr_dtr_bit = (1 << 1);
 990		up->gis_shift = 2;
 991	} else {
 992		up->pvr_dsr_bit = (1 << 3);
 993		up->pvr_dtr_bit = (1 << 2);
 994		up->gis_shift = 0;
 995	}
 996	up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
 997	writeb(up->cached_pvr, &up->regs->w.pvr);
 998	up->cached_mode = readb(&up->regs->rw.mode);
 999	up->cached_mode |= SAB82532_MODE_FRTS;
1000	writeb(up->cached_mode, &up->regs->rw.mode);
1001	up->cached_mode |= SAB82532_MODE_RTS;
1002	writeb(up->cached_mode, &up->regs->rw.mode);
1003
1004	up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
1005	up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
1006
1007	return 0;
1008}
1009
1010static int __devinit sab_probe(struct platform_device *op)
1011{
1012	static int inst;
1013	struct uart_sunsab_port *up;
1014	int err;
1015
1016	up = &sunsab_ports[inst * 2];
1017
1018	err = sunsab_init_one(&up[0], op,
1019			      0,
1020			      (inst * 2) + 0);
1021	if (err)
1022		goto out;
1023
1024	err = sunsab_init_one(&up[1], op,
1025			      sizeof(union sab82532_async_regs),
1026			      (inst * 2) + 1);
1027	if (err)
1028		goto out1;
1029
1030	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1031				&sunsab_reg, up[0].port.line,
1032				false);
1033
1034	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1035				&sunsab_reg, up[1].port.line,
1036				false);
1037
1038	err = uart_add_one_port(&sunsab_reg, &up[0].port);
1039	if (err)
1040		goto out2;
1041
1042	err = uart_add_one_port(&sunsab_reg, &up[1].port);
1043	if (err)
1044		goto out3;
1045
1046	dev_set_drvdata(&op->dev, &up[0]);
1047
1048	inst++;
1049
1050	return 0;
1051
1052out3:
1053	uart_remove_one_port(&sunsab_reg, &up[0].port);
1054out2:
1055	of_iounmap(&op->resource[0],
1056		   up[1].port.membase,
1057		   sizeof(union sab82532_async_regs));
1058out1:
1059	of_iounmap(&op->resource[0],
1060		   up[0].port.membase,
1061		   sizeof(union sab82532_async_regs));
1062out:
1063	return err;
1064}
1065
1066static int __devexit sab_remove(struct platform_device *op)
1067{
1068	struct uart_sunsab_port *up = dev_get_drvdata(&op->dev);
1069
1070	uart_remove_one_port(&sunsab_reg, &up[1].port);
1071	uart_remove_one_port(&sunsab_reg, &up[0].port);
1072	of_iounmap(&op->resource[0],
1073		   up[1].port.membase,
1074		   sizeof(union sab82532_async_regs));
1075	of_iounmap(&op->resource[0],
1076		   up[0].port.membase,
1077		   sizeof(union sab82532_async_regs));
1078
1079	dev_set_drvdata(&op->dev, NULL);
1080
1081	return 0;
1082}
1083
1084static const struct of_device_id sab_match[] = {
1085	{
1086		.name = "se",
1087	},
1088	{
1089		.name = "serial",
1090		.compatible = "sab82532",
1091	},
1092	{},
1093};
1094MODULE_DEVICE_TABLE(of, sab_match);
1095
1096static struct platform_driver sab_driver = {
1097	.driver = {
1098		.name = "sab",
1099		.owner = THIS_MODULE,
1100		.of_match_table = sab_match,
1101	},
1102	.probe		= sab_probe,
1103	.remove		= __devexit_p(sab_remove),
1104};
1105
1106static int __init sunsab_init(void)
1107{
1108	struct device_node *dp;
1109	int err;
1110	int num_channels = 0;
1111
1112	for_each_node_by_name(dp, "se")
1113		num_channels += 2;
1114	for_each_node_by_name(dp, "serial") {
1115		if (of_device_is_compatible(dp, "sab82532"))
1116			num_channels += 2;
1117	}
1118
1119	if (num_channels) {
1120		sunsab_ports = kzalloc(sizeof(struct uart_sunsab_port) *
1121				       num_channels, GFP_KERNEL);
1122		if (!sunsab_ports)
1123			return -ENOMEM;
1124
1125		err = sunserial_register_minors(&sunsab_reg, num_channels);
1126		if (err) {
1127			kfree(sunsab_ports);
1128			sunsab_ports = NULL;
1129
1130			return err;
1131		}
1132	}
1133
1134	return platform_driver_register(&sab_driver);
1135}
1136
1137static void __exit sunsab_exit(void)
1138{
1139	platform_driver_unregister(&sab_driver);
1140	if (sunsab_reg.nr) {
1141		sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
1142	}
1143
1144	kfree(sunsab_ports);
1145	sunsab_ports = NULL;
1146}
1147
1148module_init(sunsab_init);
1149module_exit(sunsab_exit);
1150
1151MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1152MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1153MODULE_LICENSE("GPL");