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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");
v6.13.7
   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.h>
  37#include <linux/platform_device.h>
  38
  39#include <linux/io.h>
  40#include <asm/irq.h>
  41#include <asm/prom.h>
  42#include <asm/setup.h>
  43
 
 
 
 
  44#include <linux/serial_core.h>
  45#include <linux/sunserialcore.h>
  46
  47#include "sunsab.h"
  48
  49struct uart_sunsab_port {
  50	struct uart_port		port;		/* Generic UART port	*/
  51	union sab82532_async_regs	__iomem *regs;	/* Chip registers	*/
  52	unsigned long			irqflags;	/* IRQ state flags	*/
  53	int				dsr;		/* Current DSR state	*/
  54	unsigned int			cec_timeout;	/* Chip poll timeout... */
  55	unsigned int			tec_timeout;	/* likewise		*/
  56	unsigned char			interrupt_mask0;/* ISR0 masking		*/
  57	unsigned char			interrupt_mask1;/* ISR1 masking		*/
  58	unsigned char			pvr_dtr_bit;	/* Which PVR bit is DTR */
  59	unsigned char			pvr_dsr_bit;	/* Which PVR bit is DSR */
  60	unsigned int			gis_shift;
  61	int				type;		/* SAB82532 version	*/
  62
  63	/* Setting configuration bits while the transmitter is active
  64	 * can cause garbage characters to get emitted by the chip.
  65	 * Therefore, we cache such writes here and do the real register
  66	 * write the next time the transmitter becomes idle.
  67	 */
  68	unsigned int			cached_ebrg;
  69	unsigned char			cached_mode;
  70	unsigned char			cached_pvr;
  71	unsigned char			cached_dafo;
  72};
  73
  74/*
  75 * This assumes you have a 29.4912 MHz clock for your UART.
  76 */
  77#define SAB_BASE_BAUD ( 29491200 / 16 )
  78
  79static char *sab82532_version[16] = {
  80	"V1.0", "V2.0", "V3.2", "V(0x03)",
  81	"V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)",
  82	"V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)",
  83	"V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)"
  84};
  85
  86#define SAB82532_MAX_TEC_TIMEOUT 200000	/* 1 character time (at 50 baud) */
  87#define SAB82532_MAX_CEC_TIMEOUT  50000	/* 2.5 TX CLKs (at 50 baud) */
  88
  89#define SAB82532_RECV_FIFO_SIZE	32      /* Standard async fifo sizes */
  90#define SAB82532_XMIT_FIFO_SIZE	32
  91
  92static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up)
  93{
  94	int timeout = up->tec_timeout;
  95
  96	while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout)
  97		udelay(1);
  98}
  99
 100static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
 101{
 102	int timeout = up->cec_timeout;
 103
 104	while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout)
 105		udelay(1);
 106}
 107
 108static struct tty_port *
 109receive_chars(struct uart_sunsab_port *up,
 110	      union sab82532_irq_status *stat)
 111{
 112	struct tty_port *port = NULL;
 113	unsigned char buf[32];
 114	int saw_console_brk = 0;
 115	int free_fifo = 0;
 116	int count = 0;
 117	int i;
 118
 119	if (up->port.state != NULL)		/* Unopened serial console */
 120		port = &up->port.state->port;
 121
 122	/* Read number of BYTES (Character + Status) available. */
 123	if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
 124		count = SAB82532_RECV_FIFO_SIZE;
 125		free_fifo++;
 126	}
 127
 128	if (stat->sreg.isr0 & SAB82532_ISR0_TCD) {
 129		count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1);
 130		free_fifo++;
 131	}
 132
 133	/* Issue a FIFO read command in case we where idle. */
 134	if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
 135		sunsab_cec_wait(up);
 136		writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
 137		return port;
 138	}
 139
 140	if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 141		free_fifo++;
 142
 143	/* Read the FIFO. */
 144	for (i = 0; i < count; i++)
 145		buf[i] = readb(&up->regs->r.rfifo[i]);
 146
 147	/* Issue Receive Message Complete command. */
 148	if (free_fifo) {
 149		sunsab_cec_wait(up);
 150		writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr);
 151	}
 152
 153	/* Count may be zero for BRK, so we check for it here */
 154	if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) &&
 155	    (up->port.line == up->port.cons->index))
 156		saw_console_brk = 1;
 157
 158	if (count == 0) {
 159		if (unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 160			stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 161					     SAB82532_ISR0_FERR);
 162			up->port.icount.brk++;
 163			uart_handle_break(&up->port);
 164		}
 165	}
 166
 167	for (i = 0; i < count; i++) {
 168		unsigned char ch = buf[i], flag;
 169
 170		flag = TTY_NORMAL;
 171		up->port.icount.rx++;
 172
 173		if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
 174						SAB82532_ISR0_FERR |
 175						SAB82532_ISR0_RFO)) ||
 176		    unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 177			/*
 178			 * For statistics only
 179			 */
 180			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 181				stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 182						     SAB82532_ISR0_FERR);
 183				up->port.icount.brk++;
 184				/*
 185				 * We do the SysRQ and SAK checking
 186				 * here because otherwise the break
 187				 * may get masked by ignore_status_mask
 188				 * or read_status_mask.
 189				 */
 190				if (uart_handle_break(&up->port))
 191					continue;
 192			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 193				up->port.icount.parity++;
 194			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 195				up->port.icount.frame++;
 196			if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 197				up->port.icount.overrun++;
 198
 199			/*
 200			 * Mask off conditions which should be ingored.
 201			 */
 202			stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
 203			stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
 204
 205			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 206				flag = TTY_BREAK;
 207			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 208				flag = TTY_PARITY;
 209			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 210				flag = TTY_FRAME;
 211		}
 212
 213		if (uart_handle_sysrq_char(&up->port, ch) || !port)
 214			continue;
 215
 216		if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
 217		    (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
 218			tty_insert_flip_char(port, ch, flag);
 219		if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 220			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 221	}
 222
 223	if (saw_console_brk)
 224		sun_do_break();
 225
 226	return port;
 227}
 228
 229static void sunsab_stop_tx(struct uart_port *);
 230static void sunsab_tx_idle(struct uart_sunsab_port *);
 231
 232static void transmit_chars(struct uart_sunsab_port *up,
 233			   union sab82532_irq_status *stat)
 234{
 235	struct tty_port *tport = &up->port.state->port;
 236	int i;
 237
 238	if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
 239		up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
 240		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 241		set_bit(SAB82532_ALLS, &up->irqflags);
 242	}
 243
 244#if 0 /* bde@nwlink.com says this check causes problems */
 245	if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
 246		return;
 247#endif
 248
 249	if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
 250		return;
 251
 252	set_bit(SAB82532_XPR, &up->irqflags);
 253	sunsab_tx_idle(up);
 254
 255	if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(&up->port)) {
 256		up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 257		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 258		return;
 259	}
 260
 261	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 262	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 263	clear_bit(SAB82532_ALLS, &up->irqflags);
 264
 265	/* Stuff 32 bytes into Transmit FIFO. */
 266	clear_bit(SAB82532_XPR, &up->irqflags);
 267	for (i = 0; i < up->port.fifosize; i++) {
 268		unsigned char ch;
 269
 270		if (!uart_fifo_get(&up->port, &ch))
 
 
 271			break;
 272
 273		writeb(ch, &up->regs->w.xfifo[i]);
 274	}
 275
 276	/* Issue a Transmit Frame command. */
 277	sunsab_cec_wait(up);
 278	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 279
 280	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
 281		uart_write_wakeup(&up->port);
 282
 283	if (kfifo_is_empty(&tport->xmit_fifo))
 284		sunsab_stop_tx(&up->port);
 285}
 286
 287static void check_status(struct uart_sunsab_port *up,
 288			 union sab82532_irq_status *stat)
 289{
 290	if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
 291		uart_handle_dcd_change(&up->port,
 292				       !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
 293
 294	if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
 295		uart_handle_cts_change(&up->port,
 296				       (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
 297
 298	if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
 299		up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
 300		up->port.icount.dsr++;
 301	}
 302
 303	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 304}
 305
 306static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
 307{
 308	struct uart_sunsab_port *up = dev_id;
 309	struct tty_port *port = NULL;
 310	union sab82532_irq_status status;
 311	unsigned long flags;
 312	unsigned char gis;
 313
 314	uart_port_lock_irqsave(&up->port, &flags);
 315
 316	status.stat = 0;
 317	gis = readb(&up->regs->r.gis) >> up->gis_shift;
 318	if (gis & 1)
 319		status.sreg.isr0 = readb(&up->regs->r.isr0);
 320	if (gis & 2)
 321		status.sreg.isr1 = readb(&up->regs->r.isr1);
 322
 323	if (status.stat) {
 324		if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 325					 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
 326		    (status.sreg.isr1 & SAB82532_ISR1_BRK))
 327			port = receive_chars(up, &status);
 328		if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
 329		    (status.sreg.isr1 & SAB82532_ISR1_CSC))
 330			check_status(up, &status);
 331		if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
 332			transmit_chars(up, &status);
 333	}
 334
 335	uart_port_unlock_irqrestore(&up->port, flags);
 336
 337	if (port)
 338		tty_flip_buffer_push(port);
 339
 340	return IRQ_HANDLED;
 341}
 342
 343/* port->lock is not held.  */
 344static unsigned int sunsab_tx_empty(struct uart_port *port)
 345{
 346	struct uart_sunsab_port *up =
 347		container_of(port, struct uart_sunsab_port, port);
 348	int ret;
 349
 350	/* Do not need a lock for a state test like this.  */
 351	if (test_bit(SAB82532_ALLS, &up->irqflags))
 352		ret = TIOCSER_TEMT;
 353	else
 354		ret = 0;
 355
 356	return ret;
 357}
 358
 359/* port->lock held by caller.  */
 360static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
 361{
 362	struct uart_sunsab_port *up =
 363		container_of(port, struct uart_sunsab_port, port);
 364
 365	if (mctrl & TIOCM_RTS) {
 366		up->cached_mode &= ~SAB82532_MODE_FRTS;
 367		up->cached_mode |= SAB82532_MODE_RTS;
 368	} else {
 369		up->cached_mode |= (SAB82532_MODE_FRTS |
 370				    SAB82532_MODE_RTS);
 371	}
 372	if (mctrl & TIOCM_DTR) {
 373		up->cached_pvr &= ~(up->pvr_dtr_bit);
 374	} else {
 375		up->cached_pvr |= up->pvr_dtr_bit;
 376	}
 377
 378	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 379	if (test_bit(SAB82532_XPR, &up->irqflags))
 380		sunsab_tx_idle(up);
 381}
 382
 383/* port->lock is held by caller and interrupts are disabled.  */
 384static unsigned int sunsab_get_mctrl(struct uart_port *port)
 385{
 386	struct uart_sunsab_port *up =
 387		container_of(port, struct uart_sunsab_port, port);
 388	unsigned char val;
 389	unsigned int result;
 390
 391	result = 0;
 392
 393	val = readb(&up->regs->r.pvr);
 394	result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
 395
 396	val = readb(&up->regs->r.vstr);
 397	result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
 398
 399	val = readb(&up->regs->r.star);
 400	result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
 401
 402	return result;
 403}
 404
 405/* port->lock held by caller.  */
 406static void sunsab_stop_tx(struct uart_port *port)
 407{
 408	struct uart_sunsab_port *up =
 409		container_of(port, struct uart_sunsab_port, port);
 410
 411	up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 412	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 413}
 414
 415/* port->lock held by caller.  */
 416static void sunsab_tx_idle(struct uart_sunsab_port *up)
 417{
 418	if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
 419		u8 tmp;
 420
 421		clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
 422		writeb(up->cached_mode, &up->regs->rw.mode);
 423		writeb(up->cached_pvr, &up->regs->rw.pvr);
 424		writeb(up->cached_dafo, &up->regs->w.dafo);
 425
 426		writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
 427		tmp = readb(&up->regs->rw.ccr2);
 428		tmp &= ~0xc0;
 429		tmp |= (up->cached_ebrg >> 2) & 0xc0;
 430		writeb(tmp, &up->regs->rw.ccr2);
 431	}
 432}
 433
 434/* port->lock held by caller.  */
 435static void sunsab_start_tx(struct uart_port *port)
 436{
 437	struct uart_sunsab_port *up =
 438		container_of(port, struct uart_sunsab_port, port);
 439	struct tty_port *tport = &up->port.state->port;
 440	int i;
 441
 442	if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port))
 443		return;
 444
 445	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 446	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 447
 448	if (!test_bit(SAB82532_XPR, &up->irqflags))
 449		return;
 450
 451	clear_bit(SAB82532_ALLS, &up->irqflags);
 452	clear_bit(SAB82532_XPR, &up->irqflags);
 453
 454	for (i = 0; i < up->port.fifosize; i++) {
 455		unsigned char ch;
 456
 457		if (!uart_fifo_get(&up->port, &ch))
 
 
 458			break;
 459
 460		writeb(ch, &up->regs->w.xfifo[i]);
 461	}
 462
 463	/* Issue a Transmit Frame command.  */
 464	sunsab_cec_wait(up);
 465	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 466}
 467
 468/* port->lock is not held.  */
 469static void sunsab_send_xchar(struct uart_port *port, char ch)
 470{
 471	struct uart_sunsab_port *up =
 472		container_of(port, struct uart_sunsab_port, port);
 473	unsigned long flags;
 474
 475	if (ch == __DISABLED_CHAR)
 476		return;
 477
 478	uart_port_lock_irqsave(&up->port, &flags);
 479
 480	sunsab_tec_wait(up);
 481	writeb(ch, &up->regs->w.tic);
 482
 483	uart_port_unlock_irqrestore(&up->port, flags);
 484}
 485
 486/* port->lock held by caller.  */
 487static void sunsab_stop_rx(struct uart_port *port)
 488{
 489	struct uart_sunsab_port *up =
 490		container_of(port, struct uart_sunsab_port, port);
 491
 492	up->interrupt_mask0 |= SAB82532_IMR0_TCD;
 493	writeb(up->interrupt_mask1, &up->regs->w.imr0);
 494}
 495
 496/* port->lock is not held.  */
 497static void sunsab_break_ctl(struct uart_port *port, int break_state)
 498{
 499	struct uart_sunsab_port *up =
 500		container_of(port, struct uart_sunsab_port, port);
 501	unsigned long flags;
 502	unsigned char val;
 503
 504	uart_port_lock_irqsave(&up->port, &flags);
 505
 506	val = up->cached_dafo;
 507	if (break_state)
 508		val |= SAB82532_DAFO_XBRK;
 509	else
 510		val &= ~SAB82532_DAFO_XBRK;
 511	up->cached_dafo = val;
 512
 513	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 514	if (test_bit(SAB82532_XPR, &up->irqflags))
 515		sunsab_tx_idle(up);
 516
 517	uart_port_unlock_irqrestore(&up->port, flags);
 518}
 519
 520/* port->lock is not held.  */
 521static int sunsab_startup(struct uart_port *port)
 522{
 523	struct uart_sunsab_port *up =
 524		container_of(port, struct uart_sunsab_port, port);
 525	unsigned long flags;
 526	unsigned char tmp;
 527	int err = request_irq(up->port.irq, sunsab_interrupt,
 528			      IRQF_SHARED, "sab", up);
 529	if (err)
 530		return err;
 531
 532	uart_port_lock_irqsave(&up->port, &flags);
 533
 534	/*
 535	 * Wait for any commands or immediate characters
 536	 */
 537	sunsab_cec_wait(up);
 538	sunsab_tec_wait(up);
 539
 540	/*
 541	 * Clear the FIFO buffers.
 542	 */
 543	writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
 544	sunsab_cec_wait(up);
 545	writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
 546
 547	/*
 548	 * Clear the interrupt registers.
 549	 */
 550	(void) readb(&up->regs->r.isr0);
 551	(void) readb(&up->regs->r.isr1);
 552
 553	/*
 554	 * Now, initialize the UART
 555	 */
 556	writeb(0, &up->regs->w.ccr0);				/* power-down */
 557	writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
 558	       SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
 559	writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
 560	writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
 561	       SAB82532_CCR2_TOE, &up->regs->w.ccr2);
 562	writeb(0, &up->regs->w.ccr3);
 563	writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
 564	up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
 565			   SAB82532_MODE_RAC);
 566	writeb(up->cached_mode, &up->regs->w.mode);
 567	writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
 568
 569	tmp = readb(&up->regs->rw.ccr0);
 570	tmp |= SAB82532_CCR0_PU;	/* power-up */
 571	writeb(tmp, &up->regs->rw.ccr0);
 572
 573	/*
 574	 * Finally, enable interrupts
 575	 */
 576	up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 577			       SAB82532_IMR0_PLLA);
 578	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 579	up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 580			       SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 581			       SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 582			       SAB82532_IMR1_XPR);
 583	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 584	set_bit(SAB82532_ALLS, &up->irqflags);
 585	set_bit(SAB82532_XPR, &up->irqflags);
 586
 587	uart_port_unlock_irqrestore(&up->port, flags);
 588
 589	return 0;
 590}
 591
 592/* port->lock is not held.  */
 593static void sunsab_shutdown(struct uart_port *port)
 594{
 595	struct uart_sunsab_port *up =
 596		container_of(port, struct uart_sunsab_port, port);
 597	unsigned long flags;
 598
 599	uart_port_lock_irqsave(&up->port, &flags);
 600
 601	/* Disable Interrupts */
 602	up->interrupt_mask0 = 0xff;
 603	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 604	up->interrupt_mask1 = 0xff;
 605	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 606
 607	/* Disable break condition */
 608	up->cached_dafo = readb(&up->regs->rw.dafo);
 609	up->cached_dafo &= ~SAB82532_DAFO_XBRK;
 610	writeb(up->cached_dafo, &up->regs->rw.dafo);
 611
 612	/* Disable Receiver */
 613	up->cached_mode &= ~SAB82532_MODE_RAC;
 614	writeb(up->cached_mode, &up->regs->rw.mode);
 615
 616	/*
 617	 * XXX FIXME
 618	 *
 619	 * If the chip is powered down here the system hangs/crashes during
 620	 * reboot or shutdown.  This needs to be investigated further,
 621	 * similar behaviour occurs in 2.4 when the driver is configured
 622	 * as a module only.  One hint may be that data is sometimes
 623	 * transmitted at 9600 baud during shutdown (regardless of the
 624	 * speed the chip was configured for when the port was open).
 625	 */
 626#if 0
 627	/* Power Down */
 628	tmp = readb(&up->regs->rw.ccr0);
 629	tmp &= ~SAB82532_CCR0_PU;
 630	writeb(tmp, &up->regs->rw.ccr0);
 631#endif
 632
 633	uart_port_unlock_irqrestore(&up->port, flags);
 634	free_irq(up->port.irq, up);
 635}
 636
 637/*
 638 * This is used to figure out the divisor speeds.
 639 *
 640 * The formula is:    Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
 641 *
 642 * with               0 <= N < 64 and 0 <= M < 16
 643 */
 644
 645static void calc_ebrg(int baud, int *n_ret, int *m_ret)
 646{
 647	int	n, m;
 648
 649	if (baud == 0) {
 650		*n_ret = 0;
 651		*m_ret = 0;
 652		return;
 653	}
 654
 655	/*
 656	 * We scale numbers by 10 so that we get better accuracy
 657	 * without having to use floating point.  Here we increment m
 658	 * until n is within the valid range.
 659	 */
 660	n = (SAB_BASE_BAUD * 10) / baud;
 661	m = 0;
 662	while (n >= 640) {
 663		n = n / 2;
 664		m++;
 665	}
 666	n = (n+5) / 10;
 667	/*
 668	 * We try very hard to avoid speeds with M == 0 since they may
 669	 * not work correctly for XTAL frequences above 10 MHz.
 670	 */
 671	if ((m == 0) && ((n & 1) == 0)) {
 672		n = n / 2;
 673		m++;
 674	}
 675	*n_ret = n - 1;
 676	*m_ret = m;
 677}
 678
 679/* Internal routine, port->lock is held and local interrupts are disabled.  */
 680static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
 681				  unsigned int iflag, unsigned int baud,
 682				  unsigned int quot)
 683{
 684	unsigned char dafo;
 685	int n, m;
 686
 687	/* Byte size and parity */
 688	switch (cflag & CSIZE) {
 689	      case CS5: dafo = SAB82532_DAFO_CHL5; break;
 690	      case CS6: dafo = SAB82532_DAFO_CHL6; break;
 691	      case CS7: dafo = SAB82532_DAFO_CHL7; break;
 692	      case CS8: dafo = SAB82532_DAFO_CHL8; break;
 693	      /* Never happens, but GCC is too dumb to figure it out */
 694	      default:  dafo = SAB82532_DAFO_CHL5; break;
 695	}
 696
 697	if (cflag & CSTOPB)
 698		dafo |= SAB82532_DAFO_STOP;
 
 
 699
 700	if (cflag & PARENB)
 701		dafo |= SAB82532_DAFO_PARE;
 
 
 702
 703	if (cflag & PARODD) {
 704		dafo |= SAB82532_DAFO_PAR_ODD;
 705	} else {
 706		dafo |= SAB82532_DAFO_PAR_EVEN;
 707	}
 708	up->cached_dafo = dafo;
 709
 710	calc_ebrg(baud, &n, &m);
 711
 712	up->cached_ebrg = n | (m << 6);
 713
 714	up->tec_timeout = (10 * 1000000) / baud;
 715	up->cec_timeout = up->tec_timeout >> 2;
 716
 717	/* CTS flow control flags */
 718	/* We encode read_status_mask and ignore_status_mask like so:
 719	 *
 720	 * ---------------------
 721	 * | ... | ISR1 | ISR0 |
 722	 * ---------------------
 723	 *  ..    15   8 7    0
 724	 */
 725
 726	up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 727				     SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
 728				     SAB82532_ISR0_CDSC);
 729	up->port.read_status_mask |= (SAB82532_ISR1_CSC |
 730				      SAB82532_ISR1_ALLS |
 731				      SAB82532_ISR1_XPR) << 8;
 732	if (iflag & INPCK)
 733		up->port.read_status_mask |= (SAB82532_ISR0_PERR |
 734					      SAB82532_ISR0_FERR);
 735	if (iflag & (IGNBRK | BRKINT | PARMRK))
 736		up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
 737
 738	/*
 739	 * Characteres to ignore
 740	 */
 741	up->port.ignore_status_mask = 0;
 742	if (iflag & IGNPAR)
 743		up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
 744						SAB82532_ISR0_FERR);
 745	if (iflag & IGNBRK) {
 746		up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
 747		/*
 748		 * If we're ignoring parity and break indicators,
 749		 * ignore overruns too (for real raw support).
 750		 */
 751		if (iflag & IGNPAR)
 752			up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
 753	}
 754
 755	/*
 756	 * ignore all characters if CREAD is not set
 757	 */
 758	if ((cflag & CREAD) == 0)
 759		up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
 760						SAB82532_ISR0_TCD);
 761
 762	uart_update_timeout(&up->port, cflag,
 763			    (up->port.uartclk / (16 * quot)));
 764
 765	/* Now schedule a register update when the chip's
 766	 * transmitter is idle.
 767	 */
 768	up->cached_mode |= SAB82532_MODE_RAC;
 769	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 770	if (test_bit(SAB82532_XPR, &up->irqflags))
 771		sunsab_tx_idle(up);
 772}
 773
 774/* port->lock is not held.  */
 775static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
 776			       const struct ktermios *old)
 777{
 778	struct uart_sunsab_port *up =
 779		container_of(port, struct uart_sunsab_port, port);
 780	unsigned long flags;
 781	unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
 782	unsigned int quot = uart_get_divisor(port, baud);
 783
 784	uart_port_lock_irqsave(&up->port, &flags);
 785	sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
 786	uart_port_unlock_irqrestore(&up->port, flags);
 787}
 788
 789static const char *sunsab_type(struct uart_port *port)
 790{
 791	struct uart_sunsab_port *up = (void *)port;
 792	static char buf[36];
 793
 794	sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
 795	return buf;
 796}
 797
 798static void sunsab_release_port(struct uart_port *port)
 799{
 800}
 801
 802static int sunsab_request_port(struct uart_port *port)
 803{
 804	return 0;
 805}
 806
 807static void sunsab_config_port(struct uart_port *port, int flags)
 808{
 809}
 810
 811static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
 812{
 813	return -EINVAL;
 814}
 815
 816static const struct uart_ops sunsab_pops = {
 817	.tx_empty	= sunsab_tx_empty,
 818	.set_mctrl	= sunsab_set_mctrl,
 819	.get_mctrl	= sunsab_get_mctrl,
 820	.stop_tx	= sunsab_stop_tx,
 821	.start_tx	= sunsab_start_tx,
 822	.send_xchar	= sunsab_send_xchar,
 823	.stop_rx	= sunsab_stop_rx,
 824	.break_ctl	= sunsab_break_ctl,
 825	.startup	= sunsab_startup,
 826	.shutdown	= sunsab_shutdown,
 827	.set_termios	= sunsab_set_termios,
 828	.type		= sunsab_type,
 829	.release_port	= sunsab_release_port,
 830	.request_port	= sunsab_request_port,
 831	.config_port	= sunsab_config_port,
 832	.verify_port	= sunsab_verify_port,
 833};
 834
 835static struct uart_driver sunsab_reg = {
 836	.owner			= THIS_MODULE,
 837	.driver_name		= "sunsab",
 838	.dev_name		= "ttyS",
 839	.major			= TTY_MAJOR,
 840};
 841
 842static struct uart_sunsab_port *sunsab_ports;
 843
 844#ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
 845
 846static void sunsab_console_putchar(struct uart_port *port, unsigned char c)
 847{
 848	struct uart_sunsab_port *up =
 849		container_of(port, struct uart_sunsab_port, port);
 850
 851	sunsab_tec_wait(up);
 852	writeb(c, &up->regs->w.tic);
 853}
 854
 855static void sunsab_console_write(struct console *con, const char *s, unsigned n)
 856{
 857	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 858	unsigned long flags;
 859	int locked = 1;
 860
 861	if (up->port.sysrq || oops_in_progress)
 862		locked = uart_port_trylock_irqsave(&up->port, &flags);
 863	else
 864		uart_port_lock_irqsave(&up->port, &flags);
 865
 866	uart_console_write(&up->port, s, n, sunsab_console_putchar);
 867	sunsab_tec_wait(up);
 868
 869	if (locked)
 870		uart_port_unlock_irqrestore(&up->port, flags);
 871}
 872
 873static int sunsab_console_setup(struct console *con, char *options)
 874{
 875	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 876	unsigned long flags;
 877	unsigned int baud, quot;
 878
 879	/*
 880	 * The console framework calls us for each and every port
 881	 * registered. Defer the console setup until the requested
 882	 * port has been properly discovered. A bit of a hack,
 883	 * though...
 884	 */
 885	if (up->port.type != PORT_SUNSAB)
 886		return -EINVAL;
 887
 888	printk("Console: ttyS%d (SAB82532)\n",
 889	       (sunsab_reg.minor - 64) + con->index);
 890
 891	sunserial_console_termios(con, up->port.dev->of_node);
 892
 893	switch (con->cflag & CBAUD) {
 894	case B150: baud = 150; break;
 895	case B300: baud = 300; break;
 896	case B600: baud = 600; break;
 897	case B1200: baud = 1200; break;
 898	case B2400: baud = 2400; break;
 899	case B4800: baud = 4800; break;
 900	default: case B9600: baud = 9600; break;
 901	case B19200: baud = 19200; break;
 902	case B38400: baud = 38400; break;
 903	case B57600: baud = 57600; break;
 904	case B115200: baud = 115200; break;
 905	case B230400: baud = 230400; break;
 906	case B460800: baud = 460800; break;
 907	}
 908
 909	/*
 910	 * Temporary fix.
 911	 */
 912	spin_lock_init(&up->port.lock);
 913
 914	/*
 915	 * Initialize the hardware
 916	 */
 917	sunsab_startup(&up->port);
 918
 919	uart_port_lock_irqsave(&up->port, &flags);
 920
 921	/*
 922	 * Finally, enable interrupts
 923	 */
 924	up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 925				SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
 926	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 927	up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 928				SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 929				SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 930				SAB82532_IMR1_XPR;
 931	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 932
 933	quot = uart_get_divisor(&up->port, baud);
 934	sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
 935	sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
 936
 937	uart_port_unlock_irqrestore(&up->port, flags);
 938
 939	return 0;
 940}
 941
 942static struct console sunsab_console = {
 943	.name	=	"ttyS",
 944	.write	=	sunsab_console_write,
 945	.device	=	uart_console_device,
 946	.setup	=	sunsab_console_setup,
 947	.flags	=	CON_PRINTBUFFER,
 948	.index	=	-1,
 949	.data	=	&sunsab_reg,
 950};
 951
 952static inline struct console *SUNSAB_CONSOLE(void)
 953{
 954	return &sunsab_console;
 955}
 956#else
 957#define SUNSAB_CONSOLE()	(NULL)
 958#define sunsab_console_init()	do { } while (0)
 959#endif
 960
 961static int sunsab_init_one(struct uart_sunsab_port *up,
 962				     struct platform_device *op,
 963				     unsigned long offset,
 964				     int line)
 965{
 966	up->port.line = line;
 967	up->port.dev = &op->dev;
 968
 969	up->port.mapbase = op->resource[0].start + offset;
 970	up->port.membase = of_ioremap(&op->resource[0], offset,
 971				      sizeof(union sab82532_async_regs),
 972				      "sab");
 973	if (!up->port.membase)
 974		return -ENOMEM;
 975	up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
 976
 977	up->port.irq = op->archdata.irqs[0];
 978
 979	up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
 980	up->port.iotype = UPIO_MEM;
 981	up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SUNSAB_CONSOLE);
 982
 983	writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
 984
 985	up->port.ops = &sunsab_pops;
 986	up->port.type = PORT_SUNSAB;
 987	up->port.uartclk = SAB_BASE_BAUD;
 988
 989	up->type = readb(&up->regs->r.vstr) & 0x0f;
 990	writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
 991	writeb(0xff, &up->regs->w.pim);
 992	if ((up->port.line & 0x1) == 0) {
 993		up->pvr_dsr_bit = (1 << 0);
 994		up->pvr_dtr_bit = (1 << 1);
 995		up->gis_shift = 2;
 996	} else {
 997		up->pvr_dsr_bit = (1 << 3);
 998		up->pvr_dtr_bit = (1 << 2);
 999		up->gis_shift = 0;
1000	}
1001	up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
1002	writeb(up->cached_pvr, &up->regs->w.pvr);
1003	up->cached_mode = readb(&up->regs->rw.mode);
1004	up->cached_mode |= SAB82532_MODE_FRTS;
1005	writeb(up->cached_mode, &up->regs->rw.mode);
1006	up->cached_mode |= SAB82532_MODE_RTS;
1007	writeb(up->cached_mode, &up->regs->rw.mode);
1008
1009	up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
1010	up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
1011
1012	return 0;
1013}
1014
1015static int sab_probe(struct platform_device *op)
1016{
1017	static int inst;
1018	struct uart_sunsab_port *up;
1019	int err;
1020
1021	up = &sunsab_ports[inst * 2];
1022
1023	err = sunsab_init_one(&up[0], op,
1024			      0,
1025			      (inst * 2) + 0);
1026	if (err)
1027		goto out;
1028
1029	err = sunsab_init_one(&up[1], op,
1030			      sizeof(union sab82532_async_regs),
1031			      (inst * 2) + 1);
1032	if (err)
1033		goto out1;
1034
1035	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1036				&sunsab_reg, up[0].port.line,
1037				false);
1038
1039	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1040				&sunsab_reg, up[1].port.line,
1041				false);
1042
1043	err = uart_add_one_port(&sunsab_reg, &up[0].port);
1044	if (err)
1045		goto out2;
1046
1047	err = uart_add_one_port(&sunsab_reg, &up[1].port);
1048	if (err)
1049		goto out3;
1050
1051	platform_set_drvdata(op, &up[0]);
1052
1053	inst++;
1054
1055	return 0;
1056
1057out3:
1058	uart_remove_one_port(&sunsab_reg, &up[0].port);
1059out2:
1060	of_iounmap(&op->resource[0],
1061		   up[1].port.membase,
1062		   sizeof(union sab82532_async_regs));
1063out1:
1064	of_iounmap(&op->resource[0],
1065		   up[0].port.membase,
1066		   sizeof(union sab82532_async_regs));
1067out:
1068	return err;
1069}
1070
1071static void sab_remove(struct platform_device *op)
1072{
1073	struct uart_sunsab_port *up = platform_get_drvdata(op);
1074
1075	uart_remove_one_port(&sunsab_reg, &up[1].port);
1076	uart_remove_one_port(&sunsab_reg, &up[0].port);
1077	of_iounmap(&op->resource[0],
1078		   up[1].port.membase,
1079		   sizeof(union sab82532_async_regs));
1080	of_iounmap(&op->resource[0],
1081		   up[0].port.membase,
1082		   sizeof(union sab82532_async_regs));
 
 
1083}
1084
1085static const struct of_device_id sab_match[] = {
1086	{
1087		.name = "se",
1088	},
1089	{
1090		.name = "serial",
1091		.compatible = "sab82532",
1092	},
1093	{},
1094};
1095MODULE_DEVICE_TABLE(of, sab_match);
1096
1097static struct platform_driver sab_driver = {
1098	.driver = {
1099		.name = "sab",
1100		.of_match_table = sab_match,
1101	},
1102	.probe		= sab_probe,
1103	.remove		= 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 = kcalloc(num_channels,
1121				       sizeof(struct uart_sunsab_port),
1122				       GFP_KERNEL);
1123		if (!sunsab_ports)
1124			return -ENOMEM;
1125
1126		err = sunserial_register_minors(&sunsab_reg, num_channels);
1127		if (err) {
1128			kfree(sunsab_ports);
1129			sunsab_ports = NULL;
1130
1131			return err;
1132		}
1133	}
1134
1135	err = platform_driver_register(&sab_driver);
1136	if (err) {
1137		kfree(sunsab_ports);
1138		sunsab_ports = NULL;
1139	}
1140
1141	return err;
1142}
1143
1144static void __exit sunsab_exit(void)
1145{
1146	platform_driver_unregister(&sab_driver);
1147	if (sunsab_reg.nr) {
1148		sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
1149	}
1150
1151	kfree(sunsab_ports);
1152	sunsab_ports = NULL;
1153}
1154
1155module_init(sunsab_init);
1156module_exit(sunsab_exit);
1157
1158MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1159MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1160MODULE_LICENSE("GPL");