drivers/serial/sunsab.c

   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  David S. Miller (davem@redhat.com)
   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@redhat.com>
  16  */
  17
  18 #include <linux/config.h>
  19 #include <linux/module.h>
  20 #include <linux/kernel.h>
  21 #include <linux/sched.h>
  22 #include <linux/errno.h>
  23 #include <linux/tty.h>
  24 #include <linux/tty_flip.h>
  25 #include <linux/major.h>
  26 #include <linux/string.h>
  27 #include <linux/ptrace.h>
  28 #include <linux/ioport.h>
  29 #include <linux/circ_buf.h>
  30 #include <linux/serial.h>
  31 #include <linux/sysrq.h>
  32 #include <linux/console.h>
  33 #include <linux/spinlock.h>
  34 #include <linux/slab.h>
  35 #include <linux/delay.h>
  36 #include <linux/init.h>
  37
  38 #include <asm/io.h>
  39 #include <asm/irq.h>
  40 #include <asm/oplib.h>
  41 #include <asm/ebus.h>
  42
  43 #if defined(CONFIG_SERIAL_SUNZILOG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  44 #define SUPPORT_SYSRQ
  45 #endif
  46
  47 #include <linux/serial_core.h>
  48
  49 #include "suncore.h"
  50 #include "sunsab.h"
  51
  52 struct 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         int                             type;           /* SAB82532 version     */
  64 };
  65
  66 /*
  67  * This assumes you have a 29.4912 MHz clock for your UART.
  68  */
  69 #define SAB_BASE_BAUD ( 29491200 / 16 )
  70
  71 static char *sab82532_version[16] = {
  72         "V1.0", "V2.0", "V3.2", "V(0x03)",
  73         "V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)",
  74         "V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)",
  75         "V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)"
  76 };
  77
  78 #define SAB82532_MAX_TEC_TIMEOUT 200000 /* 1 character time (at 50 baud) */
  79 #define SAB82532_MAX_CEC_TIMEOUT  50000 /* 2.5 TX CLKs (at 50 baud) */
  80
  81 #define SAB82532_RECV_FIFO_SIZE 32      /* Standard async fifo sizes */
  82 #define SAB82532_XMIT_FIFO_SIZE 32
  83
  84 static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up)
  85 {
  86         int timeout = up->tec_timeout;
  87
  88         while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout)
  89                 udelay(1);
  90 }
  91
  92 static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
  93 {
  94         int timeout = up->cec_timeout;
  95
  96         while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout)
  97                 udelay(1);
  98 }
  99
 100 static struct tty_struct *
 101 receive_chars(struct uart_sunsab_port *up,
 102               union sab82532_irq_status *stat,
 103               struct pt_regs *regs)
 104 {
 105         struct tty_struct *tty = NULL;
 106         unsigned char buf[32];
 107         int saw_console_brk = 0;
 108         int free_fifo = 0;
 109         int count = 0;
 110         int i;
 111
 112         if (up->port.info != NULL)              /* Unopened serial console */
 113                 tty = up->port.info->tty;
 114
 115         /* Read number of BYTES (Character + Status) available. */
 116         if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
 117                 count = SAB82532_RECV_FIFO_SIZE;
 118                 free_fifo++;
 119         }
 120
 121         if (stat->sreg.isr0 & SAB82532_ISR0_TCD) {
 122                 count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1);
 123                 free_fifo++;
 124         }
 125
 126         /* Issue a FIFO read command in case we where idle. */
 127         if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
 128                 sunsab_cec_wait(up);
 129                 writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
 130                 return tty;
 131         }
 132
 133         if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 134                 free_fifo++;
 135
 136         /* Read the FIFO. */
 137         for (i = 0; i < count; i++)
 138                 buf[i] = readb(&up->regs->r.rfifo[i]);
 139
 140         /* Issue Receive Message Complete command. */
 141         if (free_fifo) {
 142                 sunsab_cec_wait(up);
 143                 writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr);
 144         }
 145
 146         /* Count may be zero for BRK, so we check for it here */
 147         if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) &&
 148             (up->port.line == up->port.cons->index))
 149                 saw_console_brk = 1;
 150
 151         for (i = 0; i < count; i++) {
 152                 unsigned char ch = buf[i];
 153
 154                 if (tty == NULL) {
 155                         uart_handle_sysrq_char(&up->port, ch, regs);
 156                         continue;
 157                 }
 158
 159                 if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
 160                         tty->flip.work.func((void *)tty);
 161                         if (tty->flip.count >= TTY_FLIPBUF_SIZE)
 162                                 return tty; // if TTY_DONT_FLIP is set
 163                 }
 164
 165                 *tty->flip.char_buf_ptr = ch;
 166                 *tty->flip.flag_buf_ptr = TTY_NORMAL;
 167                 up->port.icount.rx++;
 168
 169                 if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
 170                                                 SAB82532_ISR0_FERR |
 171                                                 SAB82532_ISR0_RFO)) ||
 172                     unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 173                         /*
 174                          * For statistics only
 175                          */
 176                         if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 177                                 stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 178                                                      SAB82532_ISR0_FERR);
 179                                 up->port.icount.brk++;
 180                                 /*
 181                                  * We do the SysRQ and SAK checking
 182                                  * here because otherwise the break
 183                                  * may get masked by ignore_status_mask
 184                                  * or read_status_mask.
 185                                  */
 186                                 if (uart_handle_break(&up->port))
 187                                         continue;
 188                         } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 189                                 up->port.icount.parity++;
 190                         else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 191                                 up->port.icount.frame++;
 192                         if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 193                                 up->port.icount.overrun++;
 194
 195                         /*
 196                          * Mask off conditions which should be ingored.
 197                          */
 198                         stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
 199                         stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
 200
 201                         if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 202                                 *tty->flip.flag_buf_ptr = TTY_BREAK;
 203                         } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 204                                 *tty->flip.flag_buf_ptr = TTY_PARITY;
 205                         else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 206                                 *tty->flip.flag_buf_ptr = TTY_FRAME;
 207                 }
 208
 209                 if (uart_handle_sysrq_char(&up->port, ch, regs))
 210                         continue;
 211
 212                 if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
 213                     (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0){
 214                         tty->flip.flag_buf_ptr++;
 215                         tty->flip.char_buf_ptr++;
 216                         tty->flip.count++;
 217                 }
 218                 if ((stat->sreg.isr0 & SAB82532_ISR0_RFO) &&
 219                     tty->flip.count < TTY_FLIPBUF_SIZE) {
 220                         /*
 221                          * Overrun is special, since it's reported
 222                          * immediately, and doesn't affect the current
 223                          * character.
 224                          */
 225                         *tty->flip.flag_buf_ptr = TTY_OVERRUN;
 226                         tty->flip.flag_buf_ptr++;
 227                         tty->flip.char_buf_ptr++;
 228                         tty->flip.count++;
 229                 }
 230         }
 231
 232         if (saw_console_brk)
 233                 sun_do_break();
 234
 235         return tty;
 236 }
 237
 238 static void sunsab_stop_tx(struct uart_port *, unsigned int);
 239
 240 static void transmit_chars(struct uart_sunsab_port *up,
 241                            union sab82532_irq_status *stat)
 242 {
 243         struct circ_buf *xmit = &up->port.info->xmit;
 244         int i;
 245
 246         if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
 247                 up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
 248                 writeb(up->interrupt_mask1, &up->regs->w.imr1);
 249                 set_bit(SAB82532_ALLS, &up->irqflags);
 250         }
 251
 252 #if 0 /* bde@nwlink.com says this check causes problems */
 253         if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
 254                 return;
 255 #endif
 256
 257         if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
 258                 return;
 259
 260         set_bit(SAB82532_XPR, &up->irqflags);
 261
 262         if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 263                 up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 264                 writeb(up->interrupt_mask1, &up->regs->w.imr1);
 265                 uart_write_wakeup(&up->port);
 266                 return;
 267         }
 268
 269         up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 270         writeb(up->interrupt_mask1, &up->regs->w.imr1);
 271         clear_bit(SAB82532_ALLS, &up->irqflags);
 272
 273         /* Stuff 32 bytes into Transmit FIFO. */
 274         clear_bit(SAB82532_XPR, &up->irqflags);
 275         for (i = 0; i < up->port.fifosize; i++) {
 276                 writeb(xmit->buf[xmit->tail],
 277                        &up->regs->w.xfifo[i]);
 278                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 279                 up->port.icount.tx++;
 280                 if (uart_circ_empty(xmit))
 281                         break;
 282         }
 283
 284         /* Issue a Transmit Frame command. */
 285         sunsab_cec_wait(up);
 286         writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 287
 288         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 289                 uart_write_wakeup(&up->port);
 290
 291         if (uart_circ_empty(xmit))
 292                 sunsab_stop_tx(&up->port, 0);
 293 }
 294
 295 static void check_status(struct uart_sunsab_port *up,
 296                          union sab82532_irq_status *stat)
 297 {
 298         if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
 299                 uart_handle_dcd_change(&up->port,
 300                                        !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
 301
 302         if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
 303                 uart_handle_cts_change(&up->port,
 304                                        (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
 305
 306         if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
 307                 up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
 308                 up->port.icount.dsr++;
 309         }
 310
 311         wake_up_interruptible(&up->port.info->delta_msr_wait);
 312 }
 313
 314 static irqreturn_t sunsab_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 315 {
 316         struct uart_sunsab_port *up = dev_id;
 317         struct tty_struct *tty;
 318         union sab82532_irq_status status;
 319         unsigned long flags;
 320
 321         spin_lock_irqsave(&up->port.lock, flags);
 322
 323         status.stat = 0;
 324         if (readb(&up->regs->r.gis) & SAB82532_GIS_ISA0)
 325                 status.sreg.isr0 = readb(&up->regs->r.isr0);
 326         if (readb(&up->regs->r.gis) & SAB82532_GIS_ISA1)
 327                 status.sreg.isr1 = readb(&up->regs->r.isr1);
 328
 329         tty = NULL;
 330         if (status.stat) {
 331                 if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 332                                          SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
 333                     (status.sreg.isr1 & SAB82532_ISR1_BRK))
 334                         tty = receive_chars(up, &status, regs);
 335                 if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
 336                     (status.sreg.isr1 & SAB82532_ISR1_CSC))
 337                         check_status(up, &status);
 338                 if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
 339                         transmit_chars(up, &status);
 340         }
 341
 342         spin_unlock(&up->port.lock);
 343
 344         if (tty)
 345                 tty_flip_buffer_push(tty);
 346
 347         up++;
 348
 349         spin_lock(&up->port.lock);
 350
 351         status.stat = 0;
 352         if (readb(&up->regs->r.gis) & SAB82532_GIS_ISB0)
 353                 status.sreg.isr0 = readb(&up->regs->r.isr0);
 354         if (readb(&up->regs->r.gis) & SAB82532_GIS_ISB1)
 355                 status.sreg.isr1 = readb(&up->regs->r.isr1);
 356
 357         tty = NULL;
 358         if (status.stat) {
 359                 if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 360                                          SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
 361                     (status.sreg.isr1 & SAB82532_ISR1_BRK))
 362
 363                         tty = receive_chars(up, &status, regs);
 364                 if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
 365                     (status.sreg.isr1 & (SAB82532_ISR1_BRK | SAB82532_ISR1_CSC)))
 366                         check_status(up, &status);
 367                 if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
 368                         transmit_chars(up, &status);
 369         }
 370
 371         spin_unlock_irqrestore(&up->port.lock, flags);
 372
 373         if (tty)
 374                 tty_flip_buffer_push(tty);
 375
 376         return IRQ_HANDLED;
 377 }
 378
 379 /* port->lock is not held.  */
 380 static unsigned int sunsab_tx_empty(struct uart_port *port)
 381 {
 382         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 383         int ret;
 384
 385         /* Do not need a lock for a state test like this.  */
 386         if (test_bit(SAB82532_ALLS, &up->irqflags))
 387                 ret = TIOCSER_TEMT;
 388         else
 389                 ret = 0;
 390
 391         return ret;
 392 }
 393
 394 /* port->lock held by caller.  */
 395 static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
 396 {
 397         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 398
 399         if (mctrl & TIOCM_RTS) {
 400                 writeb(readb(&up->regs->rw.mode) & ~SAB82532_MODE_FRTS,
 401                        &up->regs->rw.mode);
 402                 writeb(readb(&up->regs->rw.mode) | SAB82532_MODE_RTS,
 403                        &up->regs->rw.mode);
 404         } else {
 405                 writeb(readb(&up->regs->rw.mode) | SAB82532_MODE_FRTS,
 406                        &up->regs->rw.mode);
 407                 writeb(readb(&up->regs->rw.mode) | SAB82532_MODE_RTS,
 408                        &up->regs->rw.mode);
 409         }
 410         if (mctrl & TIOCM_DTR) {
 411                 writeb(readb(&up->regs->rw.pvr) & ~(up->pvr_dtr_bit), &up->regs->rw.pvr);
 412         } else {
 413                 writeb(readb(&up->regs->rw.pvr) | up->pvr_dtr_bit, &up->regs->rw.pvr);
 414         }
 415 }
 416
 417 /* port->lock is not held.  */
 418 static unsigned int sunsab_get_mctrl(struct uart_port *port)
 419 {
 420         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 421         unsigned long flags;
 422         unsigned char val;
 423         unsigned int result;
 424
 425         result = 0;
 426
 427         spin_lock_irqsave(&up->port.lock, flags);
 428
 429         val = readb(&up->regs->r.pvr);
 430         result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
 431
 432         val = readb(&up->regs->r.vstr);
 433         result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
 434
 435         val = readb(&up->regs->r.star);
 436         result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
 437
 438         spin_unlock_irqrestore(&up->port.lock, flags);
 439
 440         return result;
 441 }
 442
 443 /* port->lock held by caller.  */
 444 static void sunsab_stop_tx(struct uart_port *port, unsigned int tty_stop)
 445 {
 446         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 447
 448         up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 449         writeb(up->interrupt_mask1, &up->regs->w.imr1);
 450 }
 451
 452 /* port->lock held by caller.  */
 453 static void sunsab_start_tx(struct uart_port *port, unsigned int tty_start)
 454 {
 455         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 456         struct circ_buf *xmit = &up->port.info->xmit;
 457         int i;
 458
 459         up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 460         writeb(up->interrupt_mask1, &up->regs->w.imr1);
 461
 462         if (!test_bit(SAB82532_XPR, &up->irqflags))
 463                 return;
 464
 465         clear_bit(SAB82532_ALLS, &up->irqflags);
 466         clear_bit(SAB82532_XPR, &up->irqflags);
 467
 468         for (i = 0; i < up->port.fifosize; i++) {
 469                 writeb(xmit->buf[xmit->tail],
 470                        &up->regs->w.xfifo[i]);
 471                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 472                 up->port.icount.tx++;
 473                 if (uart_circ_empty(xmit))
 474                         break;
 475         }
 476
 477         /* Issue a Transmit Frame command.  */
 478         sunsab_cec_wait(up);
 479         writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 480 }
 481
 482 /* port->lock is not held.  */
 483 static void sunsab_send_xchar(struct uart_port *port, char ch)
 484 {
 485         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 486         unsigned long flags;
 487
 488         spin_lock_irqsave(&up->port.lock, flags);
 489
 490         sunsab_tec_wait(up);
 491         writeb(ch, &up->regs->w.tic);
 492
 493         spin_unlock_irqrestore(&up->port.lock, flags);
 494 }
 495
 496 /* port->lock held by caller.  */
 497 static void sunsab_stop_rx(struct uart_port *port)
 498 {
 499         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 500
 501         up->interrupt_mask0 |= SAB82532_ISR0_TCD;
 502         writeb(up->interrupt_mask1, &up->regs->w.imr0);
 503 }
 504
 505 /* port->lock held by caller.  */
 506 static void sunsab_enable_ms(struct uart_port *port)
 507 {
 508         /* For now we always receive these interrupts.  */
 509 }
 510
 511 /* port->lock is not held.  */
 512 static void sunsab_break_ctl(struct uart_port *port, int break_state)
 513 {
 514         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 515         unsigned long flags;
 516         unsigned char val;
 517
 518         spin_lock_irqsave(&up->port.lock, flags);
 519
 520         val = readb(&up->regs->rw.dafo);
 521         if (break_state)
 522                 val |= SAB82532_DAFO_XBRK;
 523         else
 524                 val &= ~SAB82532_DAFO_XBRK;
 525         writeb(val, &up->regs->rw.dafo);
 526
 527         spin_unlock_irqrestore(&up->port.lock, flags);
 528 }
 529
 530 /* port->lock is not held.  */
 531 static int sunsab_startup(struct uart_port *port)
 532 {
 533         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 534         unsigned long flags;
 535         unsigned char tmp;
 536
 537         spin_lock_irqsave(&up->port.lock, flags);
 538
 539         /*
 540          * Wait for any commands or immediate characters
 541          */
 542         sunsab_cec_wait(up);
 543         sunsab_tec_wait(up);
 544
 545         /*
 546          * Clear the FIFO buffers.
 547          */
 548         writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
 549         sunsab_cec_wait(up);
 550         writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
 551
 552         /*
 553          * Clear the interrupt registers.
 554          */
 555         (void) readb(&up->regs->r.isr0);
 556         (void) readb(&up->regs->r.isr1);
 557
 558         /*
 559          * Now, initialize the UART
 560          */
 561         writeb(0, &up->regs->w.ccr0);                           /* power-down */
 562         writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
 563                SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
 564         writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
 565         writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
 566                SAB82532_CCR2_TOE, &up->regs->w.ccr2);
 567         writeb(0, &up->regs->w.ccr3);
 568         writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
 569         writeb(SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
 570                SAB82532_MODE_RAC, &up->regs->w.mode);
 571         writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
 572
 573         tmp = readb(&up->regs->rw.ccr0);
 574         tmp |= SAB82532_CCR0_PU;        /* power-up */
 575         writeb(tmp, &up->regs->rw.ccr0);
 576
 577         /*
 578          * Finally, enable interrupts
 579          */
 580         up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 581                                SAB82532_IMR0_PLLA);
 582         writeb(up->interrupt_mask0, &up->regs->w.imr0);
 583         up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 584                                SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 585                                SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 586                                SAB82532_IMR1_XPR);
 587         writeb(up->interrupt_mask1, &up->regs->w.imr1);
 588         set_bit(SAB82532_ALLS, &up->irqflags);
 589         set_bit(SAB82532_XPR, &up->irqflags);
 590
 591         spin_unlock_irqrestore(&up->port.lock, flags);
 592
 593         return 0;
 594 }
 595
 596 /* port->lock is not held.  */
 597 static void sunsab_shutdown(struct uart_port *port)
 598 {
 599         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 600         unsigned long flags;
 601         unsigned char tmp;
 602
 603         spin_lock_irqsave(&up->port.lock, flags);
 604
 605         /* Disable Interrupts */
 606         up->interrupt_mask0 = 0xff;
 607         writeb(up->interrupt_mask0, &up->regs->w.imr0);
 608         up->interrupt_mask1 = 0xff;
 609         writeb(up->interrupt_mask1, &up->regs->w.imr1);
 610
 611         /* Disable break condition */
 612         tmp = readb(&up->regs->rw.dafo);
 613         tmp &= ~SAB82532_DAFO_XBRK;
 614         writeb(tmp, &up->regs->rw.dafo);
 615
 616         /* Disable Receiver */
 617         tmp = readb(&up->regs->rw.mode);
 618         tmp &= ~SAB82532_MODE_RAC;
 619         writeb(tmp, &up->regs->rw.mode);
 620
 621         /*
 622          * XXX FIXME
 623          *
 624          * If the chip is powered down here the system hangs/crashes during
 625          * reboot or shutdown.  This needs to be investigated further,
 626          * similar behaviour occurs in 2.4 when the driver is configured
 627          * as a module only.  One hint may be that data is sometimes
 628          * transmitted at 9600 baud during shutdown (regardless of the
 629          * speed the chip was configured for when the port was open).
 630          */
 631 #if 0
 632         /* Power Down */
 633         tmp = readb(&up->regs->rw.ccr0);
 634         tmp &= ~SAB82532_CCR0_PU;
 635         writeb(tmp, &up->regs->rw.ccr0);
 636 #endif
 637
 638         spin_unlock_irqrestore(&up->port.lock, flags);
 639 }
 640
 641 /*
 642  * This is used to figure out the divisor speeds.
 643  *
 644  * The formula is:    Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
 645  *
 646  * with               0 <= N < 64 and 0 <= M < 16
 647  */
 648
 649 static void calc_ebrg(int baud, int *n_ret, int *m_ret)
 650 {
 651         int     n, m;
 652
 653         if (baud == 0) {
 654                 *n_ret = 0;
 655                 *m_ret = 0;
 656                 return;
 657         }
 658
 659         /*
 660          * We scale numbers by 10 so that we get better accuracy
 661          * without having to use floating point.  Here we increment m
 662          * until n is within the valid range.
 663          */
 664         n = (SAB_BASE_BAUD * 10) / baud;
 665         m = 0;
 666         while (n >= 640) {
 667                 n = n / 2;
 668                 m++;
 669         }
 670         n = (n+5) / 10;
 671         /*
 672          * We try very hard to avoid speeds with M == 0 since they may
 673          * not work correctly for XTAL frequences above 10 MHz.
 674          */
 675         if ((m == 0) && ((n & 1) == 0)) {
 676                 n = n / 2;
 677                 m++;
 678         }
 679         *n_ret = n - 1;
 680         *m_ret = m;
 681 }
 682
 683 /* Internal routine, port->lock is held and local interrupts are disabled.  */
 684 static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
 685                                   unsigned int iflag, int baud)
 686 {
 687         unsigned int ebrg;
 688         unsigned char dafo;
 689         int bits, n, m;
 690
 691         /* Byte size and parity */
 692         switch (cflag & CSIZE) {
 693               case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 694               case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
 695               case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
 696               case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
 697               /* Never happens, but GCC is too dumb to figure it out */
 698               default:  dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 699         }
 700
 701         if (cflag & CSTOPB) {
 702                 dafo |= SAB82532_DAFO_STOP;
 703                 bits++;
 704         }
 705
 706         if (cflag & PARENB) {
 707                 dafo |= SAB82532_DAFO_PARE;
 708                 bits++;
 709         }
 710
 711         if (cflag & PARODD) {
 712                 dafo |= SAB82532_DAFO_PAR_ODD;
 713         } else {
 714                 dafo |= SAB82532_DAFO_PAR_EVEN;
 715         }
 716
 717         calc_ebrg(baud, &n, &m);
 718
 719         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 & (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         /* Now bang the new settings into the chip.  */
 770         sunsab_cec_wait(up);
 771         sunsab_tec_wait(up);
 772         writeb(dafo, &up->regs->w.dafo);
 773         writeb(ebrg & 0xff, &up->regs->w.bgr);
 774         writeb((readb(&up->regs->rw.ccr2) & ~0xc0) | ((ebrg >> 2) & 0xc0),
 775                &up->regs->rw.ccr2);
 776
 777         writeb(readb(&up->regs->rw.mode) | SAB82532_MODE_RAC, &up->regs->rw.mode);
 778
 779 }
 780
 781 /* port->lock is not held.  */
 782 static void sunsab_set_termios(struct uart_port *port, struct termios *termios,
 783                                struct termios *old)
 784 {
 785         struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 786         unsigned long flags;
 787         int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
 788
 789         spin_lock_irqsave(&up->port.lock, flags);
 790         sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud);
 791         spin_unlock_irqrestore(&up->port.lock, flags);
 792 }
 793
 794 static const char *sunsab_type(struct uart_port *port)
 795 {
 796         struct uart_sunsab_port *up = (void *)port;
 797         static char buf[36];
 798
 799         sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
 800         return buf;
 801 }
 802
 803 static void sunsab_release_port(struct uart_port *port)
 804 {
 805 }
 806
 807 static int sunsab_request_port(struct uart_port *port)
 808 {
 809         return 0;
 810 }
 811
 812 static void sunsab_config_port(struct uart_port *port, int flags)
 813 {
 814 }
 815
 816 static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
 817 {
 818         return -EINVAL;
 819 }
 820
 821 static struct uart_ops sunsab_pops = {
 822         .tx_empty       = sunsab_tx_empty,
 823         .set_mctrl      = sunsab_set_mctrl,
 824         .get_mctrl      = sunsab_get_mctrl,
 825         .stop_tx        = sunsab_stop_tx,
 826         .start_tx       = sunsab_start_tx,
 827         .send_xchar     = sunsab_send_xchar,
 828         .stop_rx        = sunsab_stop_rx,
 829         .enable_ms      = sunsab_enable_ms,
 830         .break_ctl      = sunsab_break_ctl,
 831         .startup        = sunsab_startup,
 832         .shutdown       = sunsab_shutdown,
 833         .set_termios    = sunsab_set_termios,
 834         .type           = sunsab_type,
 835         .release_port   = sunsab_release_port,
 836         .request_port   = sunsab_request_port,
 837         .config_port    = sunsab_config_port,
 838         .verify_port    = sunsab_verify_port,
 839 };
 840
 841 static struct uart_driver sunsab_reg = {
 842         .owner                  = THIS_MODULE,
 843         .driver_name            = "serial",
 844         .devfs_name             = "tts/",
 845         .dev_name               = "ttyS",
 846         .major                  = TTY_MAJOR,
 847 };
 848
 849 static struct uart_sunsab_port *sunsab_ports;
 850 static int num_channels;
 851
 852 #ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
 853
 854 static __inline__ void sunsab_console_putchar(struct uart_sunsab_port *up, char c)
 855 {
 856         unsigned long flags;
 857
 858         spin_lock_irqsave(&up->port.lock, flags);
 859
 860         sunsab_tec_wait(up);
 861         writeb(c, &up->regs->w.tic);
 862
 863         spin_unlock_irqrestore(&up->port.lock, flags);
 864 }
 865
 866 static void sunsab_console_write(struct console *con, const char *s, unsigned n)
 867 {
 868         struct uart_sunsab_port *up = &sunsab_ports[con->index];
 869         int i;
 870
 871         for (i = 0; i < n; i++) {
 872                 if (*s == '\n')
 873                         sunsab_console_putchar(up, '\r');
 874                 sunsab_console_putchar(up, *s++);
 875         }
 876         sunsab_tec_wait(up);
 877 }
 878
 879 static int sunsab_console_setup(struct console *con, char *options)
 880 {
 881         struct uart_sunsab_port *up = &sunsab_ports[con->index];
 882         unsigned long flags;
 883         int baud;
 884
 885         printk("Console: ttyS%d (SAB82532)\n",
 886                (sunsab_reg.minor - 64) + con->index);
 887
 888         sunserial_console_termios(con);
 889
 890         /* Firmware console speed is limited to 150-->38400 baud so
 891          * this hackish cflag thing is OK.
 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         };
 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         sunsab_convert_to_sab(up, con->cflag, 0, baud);
 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
 937 static 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 #define SUNSAB_CONSOLE  (&sunsab_console)
 947
 948 static void __init sunsab_console_init(void)
 949 {
 950         int i;
 951
 952         if (con_is_present())
 953                 return;
 954
 955         for (i = 0; i < num_channels; i++) {
 956                 int this_minor = sunsab_reg.minor + i;
 957
 958                 if ((this_minor - 64) == (serial_console - 1))
 959                         break;
 960         }
 961         if (i == num_channels)
 962                 return;
 963
 964         sunsab_console.index = i;
 965         register_console(&sunsab_console);
 966 }
 967 #else
 968 #define SUNSAB_CONSOLE          (NULL)
 969 #define sunsab_console_init()   do { } while (0)
 970 #endif
 971
 972 static void __init for_each_sab_edev(void (*callback)(struct linux_ebus_device *, void *), void *arg)
 973 {
 974         struct linux_ebus *ebus;
 975         struct linux_ebus_device *edev = NULL;
 976
 977         for_each_ebus(ebus) {
 978                 for_each_ebusdev(edev, ebus) {
 979                         if (!strcmp(edev->prom_name, "se")) {
 980                                 callback(edev, arg);
 981                                 continue;
 982                         } else if (!strcmp(edev->prom_name, "serial")) {
 983                                 char compat[32];
 984                                 int clen;
 985
 986                                 /* On RIO this can be an SE, check it.  We could
 987                                  * just check ebus->is_rio, but this is more portable.
 988                                  */
 989                                 clen = prom_getproperty(edev->prom_node, "compatible",
 990                                                         compat, sizeof(compat));
 991                                 if (clen > 0) {
 992                                         if (strncmp(compat, "sab82532", 8) == 0) {
 993                                                 callback(edev, arg);
 994                                                 continue;
 995                                         }
 996                                 }
 997                         }
 998                 }
 999         }
1000 }
1001
1002 static void __init sab_count_callback(struct linux_ebus_device *edev, void *arg)
1003 {
1004         int *count_p = arg;
1005
1006         (*count_p)++;
1007 }
1008
1009 static void __init sab_attach_callback(struct linux_ebus_device *edev, void *arg)
1010 {
1011         int *instance_p = arg;
1012         struct uart_sunsab_port *up;
1013         unsigned long regs, offset;
1014         int i;
1015
1016         /* Note: ports are located in reverse order */
1017         regs = edev->resource[0].start;
1018         offset = sizeof(union sab82532_async_regs);
1019         for (i = 0; i < 2; i++) {
1020                 up = &sunsab_ports[(*instance_p * 2) + 1 - i];
1021
1022                 memset(up, 0, sizeof(*up));
1023                 up->regs = ioremap(regs + offset, sizeof(union sab82532_async_regs));
1024                 up->port.irq = edev->irqs[0];
1025                 up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
1026                 up->port.mapbase = (unsigned long)up->regs;
1027                 up->port.iotype = SERIAL_IO_MEM;
1028
1029                 writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
1030
1031                 offset -= sizeof(union sab82532_async_regs);
1032         }
1033
1034         (*instance_p)++;
1035 }
1036
1037 static int __init probe_for_sabs(void)
1038 {
1039         int this_sab = 0;
1040
1041         /* Find device instances.  */
1042         for_each_sab_edev(&sab_count_callback, &this_sab);
1043         if (!this_sab)
1044                 return -ENODEV;
1045
1046         /* Allocate tables.  */
1047         sunsab_ports = kmalloc(sizeof(struct uart_sunsab_port) * this_sab * 2,
1048                                GFP_KERNEL);
1049         if (!sunsab_ports)
1050                 return -ENOMEM;
1051
1052         num_channels = this_sab * 2;
1053
1054         this_sab = 0;
1055         for_each_sab_edev(&sab_attach_callback, &this_sab);
1056         return 0;
1057 }
1058
1059 static void __init sunsab_init_hw(void)
1060 {
1061         int i;
1062
1063         for (i = 0; i < num_channels; i++) {
1064                 struct uart_sunsab_port *up = &sunsab_ports[i];
1065
1066                 up->port.line = i;
1067                 up->port.ops = &sunsab_pops;
1068                 up->port.type = PORT_SUNSAB;
1069                 up->port.uartclk = SAB_BASE_BAUD;
1070
1071                 up->type = readb(&up->regs->r.vstr) & 0x0f;
1072                 writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
1073                 writeb(0xff, &up->regs->w.pim);
1074                 if (up->port.line == 0) {
1075                         up->pvr_dsr_bit = (1 << 0);
1076                         up->pvr_dtr_bit = (1 << 1);
1077                 } else {
1078                         up->pvr_dsr_bit = (1 << 3);
1079                         up->pvr_dtr_bit = (1 << 2);
1080                 }
1081                 writeb((1 << 1) | (1 << 2) | (1 << 4), &up->regs->w.pvr);
1082                 writeb(readb(&up->regs->rw.mode) | SAB82532_MODE_FRTS,
1083                        &up->regs->rw.mode);
1084                 writeb(readb(&up->regs->rw.mode) | SAB82532_MODE_RTS,
1085                        &up->regs->rw.mode);
1086
1087                 up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
1088                 up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
1089
1090                 if (!(up->port.line & 0x01)) {
1091                         if (request_irq(up->port.irq, sunsab_interrupt,
1092                                         SA_SHIRQ, "serial(sab82532)", up)) {
1093                                 printk("sunsab%d: can't get IRQ %x\n",
1094                                        i, up->port.irq);
1095                                 continue;
1096                         }
1097                 }
1098         }
1099 }
1100
1101 static int __init sunsab_init(void)
1102 {
1103         int ret = probe_for_sabs();
1104         int i;
1105
1106         if (ret < 0)
1107                 return ret;
1108
1109         sunsab_init_hw();
1110
1111         sunsab_reg.minor = sunserial_current_minor;
1112         sunsab_reg.nr = num_channels;
1113         sunsab_reg.cons = SUNSAB_CONSOLE;
1114
1115         ret = uart_register_driver(&sunsab_reg);
1116         if (ret < 0) {
1117                 int i;
1118
1119                 for (i = 0; i < num_channels; i++) {
1120                         struct uart_sunsab_port *up = &sunsab_ports[i];
1121
1122                         if (!(up->port.line & 0x01))
1123                                 free_irq(up->port.irq, up);
1124                         iounmap(up->regs);
1125                 }
1126                 kfree(sunsab_ports);
1127                 sunsab_ports = NULL;
1128
1129                 return ret;
1130         }
1131
1132         sunserial_current_minor += num_channels;
1133
1134         sunsab_console_init();
1135
1136         for (i = 0; i < num_channels; i++) {
1137                 struct uart_sunsab_port *up = &sunsab_ports[i];
1138
1139                 uart_add_one_port(&sunsab_reg, &up->port);
1140         }
1141
1142         return 0;
1143 }
1144
1145 static void __exit sunsab_exit(void)
1146 {
1147         int i;
1148
1149         for (i = 0; i < num_channels; i++) {
1150                 struct uart_sunsab_port *up = &sunsab_ports[i];
1151
1152                 uart_remove_one_port(&sunsab_reg, &up->port);
1153
1154                 if (!(up->port.line & 0x01))
1155                         free_irq(up->port.irq, up);
1156                 iounmap(up->regs);
1157         }
1158
1159         sunserial_current_minor -= num_channels;
1160         uart_unregister_driver(&sunsab_reg);
1161
1162         kfree(sunsab_ports);
1163         sunsab_ports = NULL;
1164 }
1165
1166 module_init(sunsab_init);
1167 module_exit(sunsab_exit);
1168
1169 MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1170 MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1171 MODULE_LICENSE("GPL");