drivers/char/vme_scc.c

   1 /*
   2  * drivers/char/vme_scc.c: MVME147, MVME162, BVME6000 SCC serial ports
   3  * implementation.
   4  * Copyright 1999 Richard Hirst <richard@sleepie.demon.co.uk>
   5  *
   6  * Based on atari_SCC.c which was
   7  *   Copyright 1994-95 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
   8  *   Partially based on PC-Linux serial.c by Linus Torvalds and Theodore Ts'o
   9  *
  10  * This file is subject to the terms and conditions of the GNU General Public
  11  * License.  See the file COPYING in the main directory of this archive
  12  * for more details.
  13  *
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/config.h>
  18 #include <linux/kdev_t.h>
  19 #include <asm/io.h>
  20 #include <linux/kernel.h>
  21 #include <linux/sched.h>
  22 #include <linux/ioport.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/errno.h>
  25 #include <linux/tty.h>
  26 #include <linux/tty_flip.h>
  27 #include <linux/mm.h>
  28 #include <linux/serial.h>
  29 #include <linux/fcntl.h>
  30 #include <linux/major.h>
  31 #include <linux/delay.h>
  32 #include <linux/slab.h>
  33 #include <linux/miscdevice.h>
  34 #include <linux/console.h>
  35 #include <linux/init.h>
  36 #include <asm/setup.h>
  37 #include <asm/bootinfo.h>
  38
  39 #ifdef CONFIG_MVME147_SCC
  40 #include <asm/mvme147hw.h>
  41 #endif
  42 #ifdef CONFIG_MVME162_SCC
  43 #include <asm/mvme16xhw.h>
  44 #endif
  45 #ifdef CONFIG_BVME6000_SCC
  46 #include <asm/bvme6000hw.h>
  47 #endif
  48
  49 #include <linux/generic_serial.h>
  50 #include "scc.h"
  51
  52
  53 #define CHANNEL_A       0
  54 #define CHANNEL_B       1
  55
  56 #define SCC_MINOR_BASE  64
  57
  58 /* Shadows for all SCC write registers */
  59 static unsigned char scc_shadow[2][16];
  60
  61 /* Location to access for SCC register access delay */
  62 static volatile unsigned char *scc_del = NULL;
  63
  64 /* To keep track of STATUS_REG state for detection of Ext/Status int source */
  65 static unsigned char scc_last_status_reg[2];
  66
  67 /***************************** Prototypes *****************************/
  68
  69 /* Function prototypes */
  70 static void scc_disable_tx_interrupts(void * ptr);
  71 static void scc_enable_tx_interrupts(void * ptr);
  72 static void scc_disable_rx_interrupts(void * ptr);
  73 static void scc_enable_rx_interrupts(void * ptr);
  74 static int  scc_get_CD(void * ptr);
  75 static void scc_shutdown_port(void * ptr);
  76 static int scc_set_real_termios(void  *ptr);
  77 static void scc_hungup(void  *ptr);
  78 static void scc_close(void  *ptr);
  79 static int scc_chars_in_buffer(void * ptr);
  80 static int scc_open(struct tty_struct * tty, struct file * filp);
  81 static int scc_ioctl(struct tty_struct * tty, struct file * filp,
  82                      unsigned int cmd, unsigned long arg);
  83 static void scc_throttle(struct tty_struct *tty);
  84 static void scc_unthrottle(struct tty_struct *tty);
  85 static irqreturn_t scc_tx_int(int irq, void *data, struct pt_regs *fp);
  86 static irqreturn_t scc_rx_int(int irq, void *data, struct pt_regs *fp);
  87 static irqreturn_t scc_stat_int(int irq, void *data, struct pt_regs *fp);
  88 static irqreturn_t scc_spcond_int(int irq, void *data, struct pt_regs *fp);
  89 static void scc_setsignals(struct scc_port *port, int dtr, int rts);
  90 static void scc_break_ctl(struct tty_struct *tty, int break_state);
  91
  92 static struct tty_driver *scc_driver;
  93
  94 struct scc_port scc_ports[2];
  95
  96 int scc_initialized = 0;
  97
  98 /*---------------------------------------------------------------------------
  99  * Interface from generic_serial.c back here
 100  *--------------------------------------------------------------------------*/
 101
 102 static struct real_driver scc_real_driver = {
 103         scc_disable_tx_interrupts,
 104         scc_enable_tx_interrupts,
 105         scc_disable_rx_interrupts,
 106         scc_enable_rx_interrupts,
 107         scc_get_CD,
 108         scc_shutdown_port,
 109         scc_set_real_termios,
 110         scc_chars_in_buffer,
 111         scc_close,
 112         scc_hungup,
 113         NULL
 114 };
 115
 116
 117 static struct tty_operations scc_ops = {
 118         .open   = scc_open,
 119         .close = gs_close,
 120         .write = gs_write,
 121         .put_char = gs_put_char,
 122         .flush_chars = gs_flush_chars,
 123         .write_room = gs_write_room,
 124         .chars_in_buffer = gs_chars_in_buffer,
 125         .flush_buffer = gs_flush_buffer,
 126         .ioctl = scc_ioctl,
 127         .throttle = scc_throttle,
 128         .unthrottle = scc_unthrottle,
 129         .set_termios = gs_set_termios,
 130         .stop = gs_stop,
 131         .start = gs_start,
 132         .hangup = gs_hangup,
 133         .break_ctl = scc_break_ctl,
 134 };
 135
 136 /*----------------------------------------------------------------------------
 137  * vme_scc_init() and support functions
 138  *---------------------------------------------------------------------------*/
 139
 140 static int scc_init_drivers(void)
 141 {
 142         int error;
 143
 144         scc_driver = alloc_tty_driver(2);
 145         if (!scc_driver)
 146                 return -ENOMEM;
 147         scc_driver->owner = THIS_MODULE;
 148         scc_driver->driver_name = "scc";
 149         scc_driver->name = "ttyS";
 150         scc_driver->devfs_name = "tts/";
 151         scc_driver->major = TTY_MAJOR;
 152         scc_driver->minor_start = SCC_MINOR_BASE;
 153         scc_driver->type = TTY_DRIVER_TYPE_SERIAL;
 154         scc_driver->subtype = SERIAL_TYPE_NORMAL;
 155         scc_driver->init_termios = tty_std_termios;
 156         scc_driver->init_termios.c_cflag =
 157           B9600 | CS8 | CREAD | HUPCL | CLOCAL;
 158         scc_driver->flags = TTY_DRIVER_REAL_RAW;
 159         tty_set_operations(scc_driver, &scc_ops);
 160
 161         if ((error = tty_register_driver(scc_driver))) {
 162                 printk(KERN_ERR "scc: Couldn't register scc driver, error = %d\n",
 163                        error);
 164                 put_tty_driver(scc_driver);
 165                 return 1;
 166         }
 167
 168         return 0;
 169 }
 170
 171
 172 /* ports[] array is indexed by line no (i.e. [0] for ttyS0, [1] for ttyS1).
 173  */
 174
 175 static void scc_init_portstructs(void)
 176 {
 177         struct scc_port *port;
 178         int i;
 179
 180         for (i = 0; i < 2; i++) {
 181                 port = scc_ports + i;
 182                 port->gs.magic = SCC_MAGIC;
 183                 port->gs.close_delay = HZ/2;
 184                 port->gs.closing_wait = 30 * HZ;
 185                 port->gs.rd = &scc_real_driver;
 186 #ifdef NEW_WRITE_LOCKING
 187                 port->gs.port_write_sem = MUTEX;
 188 #endif
 189                 init_waitqueue_head(&port->gs.open_wait);
 190                 init_waitqueue_head(&port->gs.close_wait);
 191         }
 192 }
 193
 194
 195 #ifdef CONFIG_MVME147_SCC
 196 static int mvme147_scc_init(void)
 197 {
 198         struct scc_port *port;
 199
 200         printk(KERN_INFO "SCC: MVME147 Serial Driver\n");
 201         /* Init channel A */
 202         port = &scc_ports[0];
 203         port->channel = CHANNEL_A;
 204         port->ctrlp = (volatile unsigned char *)M147_SCC_A_ADDR;
 205         port->datap = port->ctrlp + 1;
 206         port->port_a = &scc_ports[0];
 207         port->port_b = &scc_ports[1];
 208         request_irq(MVME147_IRQ_SCCA_TX, scc_tx_int, SA_INTERRUPT,
 209                             "SCC-A TX", port);
 210         request_irq(MVME147_IRQ_SCCA_STAT, scc_stat_int, SA_INTERRUPT,
 211                             "SCC-A status", port);
 212         request_irq(MVME147_IRQ_SCCA_RX, scc_rx_int, SA_INTERRUPT,
 213                             "SCC-A RX", port);
 214         request_irq(MVME147_IRQ_SCCA_SPCOND, scc_spcond_int, SA_INTERRUPT,
 215                             "SCC-A special cond", port);
 216         {
 217                 SCC_ACCESS_INIT(port);
 218
 219                 /* disable interrupts for this channel */
 220                 SCCwrite(INT_AND_DMA_REG, 0);
 221                 /* Set the interrupt vector */
 222                 SCCwrite(INT_VECTOR_REG, MVME147_IRQ_SCC_BASE);
 223                 /* Interrupt parameters: vector includes status, status low */
 224                 SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
 225                 SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
 226         }
 227
 228         /* Init channel B */
 229         port = &scc_ports[1];
 230         port->channel = CHANNEL_B;
 231         port->ctrlp = (volatile unsigned char *)M147_SCC_B_ADDR;
 232         port->datap = port->ctrlp + 1;
 233         port->port_a = &scc_ports[0];
 234         port->port_b = &scc_ports[1];
 235         request_irq(MVME147_IRQ_SCCB_TX, scc_tx_int, SA_INTERRUPT,
 236                             "SCC-B TX", port);
 237         request_irq(MVME147_IRQ_SCCB_STAT, scc_stat_int, SA_INTERRUPT,
 238                             "SCC-B status", port);
 239         request_irq(MVME147_IRQ_SCCB_RX, scc_rx_int, SA_INTERRUPT,
 240                             "SCC-B RX", port);
 241         request_irq(MVME147_IRQ_SCCB_SPCOND, scc_spcond_int, SA_INTERRUPT,
 242                             "SCC-B special cond", port);
 243         {
 244                 SCC_ACCESS_INIT(port);
 245
 246                 /* disable interrupts for this channel */
 247                 SCCwrite(INT_AND_DMA_REG, 0);
 248         }
 249
 250         /* Ensure interrupts are enabled in the PCC chip */
 251         m147_pcc->serial_cntrl=PCC_LEVEL_SERIAL|PCC_INT_ENAB;
 252
 253         /* Initialise the tty driver structures and register */
 254         scc_init_portstructs();
 255         scc_init_drivers();
 256
 257         return 0;
 258 }
 259 #endif
 260
 261
 262 #ifdef CONFIG_MVME162_SCC
 263 static int mvme162_scc_init(void)
 264 {
 265         struct scc_port *port;
 266
 267         if (!(mvme16x_config & MVME16x_CONFIG_GOT_SCCA))
 268                 return (-ENODEV);
 269
 270         printk(KERN_INFO "SCC: MVME162 Serial Driver\n");
 271         /* Init channel A */
 272         port = &scc_ports[0];
 273         port->channel = CHANNEL_A;
 274         port->ctrlp = (volatile unsigned char *)MVME_SCC_A_ADDR;
 275         port->datap = port->ctrlp + 2;
 276         port->port_a = &scc_ports[0];
 277         port->port_b = &scc_ports[1];
 278         request_irq(MVME162_IRQ_SCCA_TX, scc_tx_int, SA_INTERRUPT,
 279                             "SCC-A TX", port);
 280         request_irq(MVME162_IRQ_SCCA_STAT, scc_stat_int, SA_INTERRUPT,
 281                             "SCC-A status", port);
 282         request_irq(MVME162_IRQ_SCCA_RX, scc_rx_int, SA_INTERRUPT,
 283                             "SCC-A RX", port);
 284         request_irq(MVME162_IRQ_SCCA_SPCOND, scc_spcond_int, SA_INTERRUPT,
 285                             "SCC-A special cond", port);
 286         {
 287                 SCC_ACCESS_INIT(port);
 288
 289                 /* disable interrupts for this channel */
 290                 SCCwrite(INT_AND_DMA_REG, 0);
 291                 /* Set the interrupt vector */
 292                 SCCwrite(INT_VECTOR_REG, MVME162_IRQ_SCC_BASE);
 293                 /* Interrupt parameters: vector includes status, status low */
 294                 SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
 295                 SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
 296         }
 297
 298         /* Init channel B */
 299         port = &scc_ports[1];
 300         port->channel = CHANNEL_B;
 301         port->ctrlp = (volatile unsigned char *)MVME_SCC_B_ADDR;
 302         port->datap = port->ctrlp + 2;
 303         port->port_a = &scc_ports[0];
 304         port->port_b = &scc_ports[1];
 305         request_irq(MVME162_IRQ_SCCB_TX, scc_tx_int, SA_INTERRUPT,
 306                             "SCC-B TX", port);
 307         request_irq(MVME162_IRQ_SCCB_STAT, scc_stat_int, SA_INTERRUPT,
 308                             "SCC-B status", port);
 309         request_irq(MVME162_IRQ_SCCB_RX, scc_rx_int, SA_INTERRUPT,
 310                             "SCC-B RX", port);
 311         request_irq(MVME162_IRQ_SCCB_SPCOND, scc_spcond_int, SA_INTERRUPT,
 312                             "SCC-B special cond", port);
 313
 314         {
 315                 SCC_ACCESS_INIT(port);  /* Either channel will do */
 316
 317                 /* disable interrupts for this channel */
 318                 SCCwrite(INT_AND_DMA_REG, 0);
 319         }
 320
 321         /* Ensure interrupts are enabled in the MC2 chip */
 322         *(volatile char *)0xfff4201d = 0x14;
 323
 324         /* Initialise the tty driver structures and register */
 325         scc_init_portstructs();
 326         scc_init_drivers();
 327
 328         return 0;
 329 }
 330 #endif
 331
 332
 333 #ifdef CONFIG_BVME6000_SCC
 334 static int bvme6000_scc_init(void)
 335 {
 336         struct scc_port *port;
 337
 338         printk(KERN_INFO "SCC: BVME6000 Serial Driver\n");
 339         /* Init channel A */
 340         port = &scc_ports[0];
 341         port->channel = CHANNEL_A;
 342         port->ctrlp = (volatile unsigned char *)BVME_SCC_A_ADDR;
 343         port->datap = port->ctrlp + 4;
 344         port->port_a = &scc_ports[0];
 345         port->port_b = &scc_ports[1];
 346         request_irq(BVME_IRQ_SCCA_TX, scc_tx_int, SA_INTERRUPT,
 347                             "SCC-A TX", port);
 348         request_irq(BVME_IRQ_SCCA_STAT, scc_stat_int, SA_INTERRUPT,
 349                             "SCC-A status", port);
 350         request_irq(BVME_IRQ_SCCA_RX, scc_rx_int, SA_INTERRUPT,
 351                             "SCC-A RX", port);
 352         request_irq(BVME_IRQ_SCCA_SPCOND, scc_spcond_int, SA_INTERRUPT,
 353                             "SCC-A special cond", port);
 354         {
 355                 SCC_ACCESS_INIT(port);
 356
 357                 /* disable interrupts for this channel */
 358                 SCCwrite(INT_AND_DMA_REG, 0);
 359                 /* Set the interrupt vector */
 360                 SCCwrite(INT_VECTOR_REG, BVME_IRQ_SCC_BASE);
 361                 /* Interrupt parameters: vector includes status, status low */
 362                 SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
 363                 SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
 364         }
 365
 366         /* Init channel B */
 367         port = &scc_ports[1];
 368         port->channel = CHANNEL_B;
 369         port->ctrlp = (volatile unsigned char *)BVME_SCC_B_ADDR;
 370         port->datap = port->ctrlp + 4;
 371         port->port_a = &scc_ports[0];
 372         port->port_b = &scc_ports[1];
 373         request_irq(BVME_IRQ_SCCB_TX, scc_tx_int, SA_INTERRUPT,
 374                             "SCC-B TX", port);
 375         request_irq(BVME_IRQ_SCCB_STAT, scc_stat_int, SA_INTERRUPT,
 376                             "SCC-B status", port);
 377         request_irq(BVME_IRQ_SCCB_RX, scc_rx_int, SA_INTERRUPT,
 378                             "SCC-B RX", port);
 379         request_irq(BVME_IRQ_SCCB_SPCOND, scc_spcond_int, SA_INTERRUPT,
 380                             "SCC-B special cond", port);
 381
 382         {
 383                 SCC_ACCESS_INIT(port);  /* Either channel will do */
 384
 385                 /* disable interrupts for this channel */
 386                 SCCwrite(INT_AND_DMA_REG, 0);
 387         }
 388
 389         /* Initialise the tty driver structures and register */
 390         scc_init_portstructs();
 391         scc_init_drivers();
 392
 393         return 0;
 394 }
 395 #endif
 396
 397
 398 static int vme_scc_init(void)
 399 {
 400         int res = -ENODEV;
 401
 402 #ifdef CONFIG_MVME147_SCC
 403         if (MACH_IS_MVME147)
 404                 res = mvme147_scc_init();
 405 #endif
 406 #ifdef CONFIG_MVME162_SCC
 407         if (MACH_IS_MVME16x)
 408                 res = mvme162_scc_init();
 409 #endif
 410 #ifdef CONFIG_BVME6000_SCC
 411         if (MACH_IS_BVME6000)
 412                 res = bvme6000_scc_init();
 413 #endif
 414         return res;
 415 }
 416
 417 module_init(vme_scc_init);
 418
 419
 420 /*---------------------------------------------------------------------------
 421  * Interrupt handlers
 422  *--------------------------------------------------------------------------*/
 423
 424 static irqreturn_t scc_rx_int(int irq, void *data, struct pt_regs *fp)
 425 {
 426         unsigned char   ch;
 427         struct scc_port *port = data;
 428         struct tty_struct *tty = port->gs.tty;
 429         SCC_ACCESS_INIT(port);
 430
 431         ch = SCCread_NB(RX_DATA_REG);
 432         if (!tty) {
 433                 printk(KERN_WARNING "scc_rx_int with NULL tty!\n");
 434                 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 435                 return IRQ_HANDLED;
 436         }
 437         if (tty->flip.count < TTY_FLIPBUF_SIZE) {
 438                 *tty->flip.char_buf_ptr = ch;
 439                 *tty->flip.flag_buf_ptr = 0;
 440                 tty->flip.flag_buf_ptr++;
 441                 tty->flip.char_buf_ptr++;
 442                 tty->flip.count++;
 443         }
 444
 445         /* Check if another character is already ready; in that case, the
 446          * spcond_int() function must be used, because this character may have an
 447          * error condition that isn't signalled by the interrupt vector used!
 448          */
 449         if (SCCread(INT_PENDING_REG) &
 450             (port->channel == CHANNEL_A ? IPR_A_RX : IPR_B_RX)) {
 451                 scc_spcond_int (irq, data, fp);
 452                 return IRQ_HANDLED;
 453         }
 454
 455         SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 456
 457         tty_flip_buffer_push(tty);
 458         return IRQ_HANDLED;
 459 }
 460
 461
 462 static irqreturn_t scc_spcond_int(int irq, void *data, struct pt_regs *fp)
 463 {
 464         struct scc_port *port = data;
 465         struct tty_struct *tty = port->gs.tty;
 466         unsigned char   stat, ch, err;
 467         int             int_pending_mask = port->channel == CHANNEL_A ?
 468                                            IPR_A_RX : IPR_B_RX;
 469         SCC_ACCESS_INIT(port);
 470
 471         if (!tty) {
 472                 printk(KERN_WARNING "scc_spcond_int with NULL tty!\n");
 473                 SCCwrite(COMMAND_REG, CR_ERROR_RESET);
 474                 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 475                 return IRQ_HANDLED;
 476         }
 477         do {
 478                 stat = SCCread(SPCOND_STATUS_REG);
 479                 ch = SCCread_NB(RX_DATA_REG);
 480
 481                 if (stat & SCSR_RX_OVERRUN)
 482                         err = TTY_OVERRUN;
 483                 else if (stat & SCSR_PARITY_ERR)
 484                         err = TTY_PARITY;
 485                 else if (stat & SCSR_CRC_FRAME_ERR)
 486                         err = TTY_FRAME;
 487                 else
 488                         err = 0;
 489
 490                 if (tty->flip.count < TTY_FLIPBUF_SIZE) {
 491                         *tty->flip.char_buf_ptr = ch;
 492                         *tty->flip.flag_buf_ptr = err;
 493                         tty->flip.flag_buf_ptr++;
 494                         tty->flip.char_buf_ptr++;
 495                         tty->flip.count++;
 496                 }
 497
 498                 /* ++TeSche: *All* errors have to be cleared manually,
 499                  * else the condition persists for the next chars
 500                  */
 501                 if (err)
 502                   SCCwrite(COMMAND_REG, CR_ERROR_RESET);
 503
 504         } while(SCCread(INT_PENDING_REG) & int_pending_mask);
 505
 506         SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 507
 508         tty_flip_buffer_push(tty);
 509         return IRQ_HANDLED;
 510 }
 511
 512
 513 static irqreturn_t scc_tx_int(int irq, void *data, struct pt_regs *fp)
 514 {
 515         struct scc_port *port = data;
 516         SCC_ACCESS_INIT(port);
 517
 518         if (!port->gs.tty) {
 519                 printk(KERN_WARNING "scc_tx_int with NULL tty!\n");
 520                 SCCmod (INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
 521                 SCCwrite(COMMAND_REG, CR_TX_PENDING_RESET);
 522                 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 523                 return IRQ_HANDLED;
 524         }
 525         while ((SCCread_NB(STATUS_REG) & SR_TX_BUF_EMPTY)) {
 526                 if (port->x_char) {
 527                         SCCwrite(TX_DATA_REG, port->x_char);
 528                         port->x_char = 0;
 529                 }
 530                 else if ((port->gs.xmit_cnt <= 0) || port->gs.tty->stopped ||
 531                                 port->gs.tty->hw_stopped)
 532                         break;
 533                 else {
 534                         SCCwrite(TX_DATA_REG, port->gs.xmit_buf[port->gs.xmit_tail++]);
 535                         port->gs.xmit_tail = port->gs.xmit_tail & (SERIAL_XMIT_SIZE-1);
 536                         if (--port->gs.xmit_cnt <= 0)
 537                                 break;
 538                 }
 539         }
 540         if ((port->gs.xmit_cnt <= 0) || port->gs.tty->stopped ||
 541                         port->gs.tty->hw_stopped) {
 542                 /* disable tx interrupts */
 543                 SCCmod (INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
 544                 SCCwrite(COMMAND_REG, CR_TX_PENDING_RESET);   /* disable tx_int on next tx underrun? */
 545                 port->gs.flags &= ~GS_TX_INTEN;
 546         }
 547         if (port->gs.tty && port->gs.xmit_cnt <= port->gs.wakeup_chars)
 548                 tty_wakeup(port->gs.tty);
 549
 550         SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 551         return IRQ_HANDLED;
 552 }
 553
 554
 555 static irqreturn_t scc_stat_int(int irq, void *data, struct pt_regs *fp)
 556 {
 557         struct scc_port *port = data;
 558         unsigned channel = port->channel;
 559         unsigned char   last_sr, sr, changed;
 560         SCC_ACCESS_INIT(port);
 561
 562         last_sr = scc_last_status_reg[channel];
 563         sr = scc_last_status_reg[channel] = SCCread_NB(STATUS_REG);
 564         changed = last_sr ^ sr;
 565
 566         if (changed & SR_DCD) {
 567                 port->c_dcd = !!(sr & SR_DCD);
 568                 if (!(port->gs.flags & ASYNC_CHECK_CD))
 569                         ;       /* Don't report DCD changes */
 570                 else if (port->c_dcd) {
 571                         wake_up_interruptible(&port->gs.open_wait);
 572                 }
 573                 else {
 574                         if (port->gs.tty)
 575                                 tty_hangup (port->gs.tty);
 576                 }
 577         }
 578         SCCwrite(COMMAND_REG, CR_EXTSTAT_RESET);
 579         SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 580         return IRQ_HANDLED;
 581 }
 582
 583
 584 /*---------------------------------------------------------------------------
 585  * generic_serial.c callback funtions
 586  *--------------------------------------------------------------------------*/
 587
 588 static void scc_disable_tx_interrupts(void *ptr)
 589 {
 590         struct scc_port *port = ptr;
 591         unsigned long   flags;
 592         SCC_ACCESS_INIT(port);
 593
 594         local_irq_save(flags);
 595         SCCmod(INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
 596         port->gs.flags &= ~GS_TX_INTEN;
 597         local_irq_restore(flags);
 598 }
 599
 600
 601 static void scc_enable_tx_interrupts(void *ptr)
 602 {
 603         struct scc_port *port = ptr;
 604         unsigned long   flags;
 605         SCC_ACCESS_INIT(port);
 606
 607         local_irq_save(flags);
 608         SCCmod(INT_AND_DMA_REG, 0xff, IDR_TX_INT_ENAB);
 609         /* restart the transmitter */
 610         scc_tx_int (0, port, 0);
 611         local_irq_restore(flags);
 612 }
 613
 614
 615 static void scc_disable_rx_interrupts(void *ptr)
 616 {
 617         struct scc_port *port = ptr;
 618         unsigned long   flags;
 619         SCC_ACCESS_INIT(port);
 620
 621         local_irq_save(flags);
 622         SCCmod(INT_AND_DMA_REG,
 623             ~(IDR_RX_INT_MASK|IDR_PARERR_AS_SPCOND|IDR_EXTSTAT_INT_ENAB), 0);
 624         local_irq_restore(flags);
 625 }
 626
 627
 628 static void scc_enable_rx_interrupts(void *ptr)
 629 {
 630         struct scc_port *port = ptr;
 631         unsigned long   flags;
 632         SCC_ACCESS_INIT(port);
 633
 634         local_irq_save(flags);
 635         SCCmod(INT_AND_DMA_REG, 0xff,
 636                 IDR_EXTSTAT_INT_ENAB|IDR_PARERR_AS_SPCOND|IDR_RX_INT_ALL);
 637         local_irq_restore(flags);
 638 }
 639
 640
 641 static int scc_get_CD(void *ptr)
 642 {
 643         struct scc_port *port = ptr;
 644         unsigned channel = port->channel;
 645
 646         return !!(scc_last_status_reg[channel] & SR_DCD);
 647 }
 648
 649
 650 static void scc_shutdown_port(void *ptr)
 651 {
 652         struct scc_port *port = ptr;
 653
 654         port->gs.flags &= ~ GS_ACTIVE;
 655         if (port->gs.tty && port->gs.tty->termios->c_cflag & HUPCL) {
 656                 scc_setsignals (port, 0, 0);
 657         }
 658 }
 659
 660
 661 static int scc_set_real_termios (void *ptr)
 662 {
 663         /* the SCC has char sizes 5,7,6,8 in that order! */
 664         static int chsize_map[4] = { 0, 2, 1, 3 };
 665         unsigned cflag, baud, chsize, channel, brgval = 0;
 666         unsigned long flags;
 667         struct scc_port *port = ptr;
 668         SCC_ACCESS_INIT(port);
 669
 670         if (!port->gs.tty || !port->gs.tty->termios) return 0;
 671
 672         channel = port->channel;
 673
 674         if (channel == CHANNEL_A)
 675                 return 0;               /* Settings controlled by boot PROM */
 676
 677         cflag  = port->gs.tty->termios->c_cflag;
 678         baud = port->gs.baud;
 679         chsize = (cflag & CSIZE) >> 4;
 680
 681         if (baud == 0) {
 682                 /* speed == 0 -> drop DTR */
 683                 local_irq_save(flags);
 684                 SCCmod(TX_CTRL_REG, ~TCR_DTR, 0);
 685                 local_irq_restore(flags);
 686                 return 0;
 687         }
 688         else if ((MACH_IS_MVME16x && (baud < 50 || baud > 38400)) ||
 689                  (MACH_IS_MVME147 && (baud < 50 || baud > 19200)) ||
 690                  (MACH_IS_BVME6000 &&(baud < 50 || baud > 76800))) {
 691                 printk(KERN_NOTICE "SCC: Bad speed requested, %d\n", baud);
 692                 return 0;
 693         }
 694
 695         if (cflag & CLOCAL)
 696                 port->gs.flags &= ~ASYNC_CHECK_CD;
 697         else
 698                 port->gs.flags |= ASYNC_CHECK_CD;
 699
 700 #ifdef CONFIG_MVME147_SCC
 701         if (MACH_IS_MVME147)
 702                 brgval = (M147_SCC_PCLK + baud/2) / (16 * 2 * baud) - 2;
 703 #endif
 704 #ifdef CONFIG_MVME162_SCC
 705         if (MACH_IS_MVME16x)
 706                 brgval = (MVME_SCC_PCLK + baud/2) / (16 * 2 * baud) - 2;
 707 #endif
 708 #ifdef CONFIG_BVME6000_SCC
 709         if (MACH_IS_BVME6000)
 710                 brgval = (BVME_SCC_RTxC + baud/2) / (16 * 2 * baud) - 2;
 711 #endif
 712         /* Now we have all parameters and can go to set them: */
 713         local_irq_save(flags);
 714
 715         /* receiver's character size and auto-enables */
 716         SCCmod(RX_CTRL_REG, ~(RCR_CHSIZE_MASK|RCR_AUTO_ENAB_MODE),
 717                         (chsize_map[chsize] << 6) |
 718                         ((cflag & CRTSCTS) ? RCR_AUTO_ENAB_MODE : 0));
 719         /* parity and stop bits (both, Tx and Rx), clock mode never changes */
 720         SCCmod (AUX1_CTRL_REG,
 721                 ~(A1CR_PARITY_MASK | A1CR_MODE_MASK),
 722                 ((cflag & PARENB
 723                   ? (cflag & PARODD ? A1CR_PARITY_ODD : A1CR_PARITY_EVEN)
 724                   : A1CR_PARITY_NONE)
 725                  | (cflag & CSTOPB ? A1CR_MODE_ASYNC_2 : A1CR_MODE_ASYNC_1)));
 726         /* sender's character size, set DTR for valid baud rate */
 727         SCCmod(TX_CTRL_REG, ~TCR_CHSIZE_MASK, chsize_map[chsize] << 5 | TCR_DTR);
 728         /* clock sources never change */
 729         /* disable BRG before changing the value */
 730         SCCmod(DPLL_CTRL_REG, ~DCR_BRG_ENAB, 0);
 731         /* BRG value */
 732         SCCwrite(TIMER_LOW_REG, brgval & 0xff);
 733         SCCwrite(TIMER_HIGH_REG, (brgval >> 8) & 0xff);
 734         /* BRG enable, and clock source never changes */
 735         SCCmod(DPLL_CTRL_REG, 0xff, DCR_BRG_ENAB);
 736
 737         local_irq_restore(flags);
 738
 739         return 0;
 740 }
 741
 742
 743 static int scc_chars_in_buffer (void *ptr)
 744 {
 745         struct scc_port *port = ptr;
 746         SCC_ACCESS_INIT(port);
 747
 748         return (SCCread (SPCOND_STATUS_REG) & SCSR_ALL_SENT) ? 0  : 1;
 749 }
 750
 751
 752 /* Comment taken from sx.c (2.4.0):
 753    I haven't the foggiest why the decrement use count has to happen
 754    here. The whole linux serial drivers stuff needs to be redesigned.
 755    My guess is that this is a hack to minimize the impact of a bug
 756    elsewhere. Thinking about it some more. (try it sometime) Try
 757    running minicom on a serial port that is driven by a modularized
 758    driver. Have the modem hangup. Then remove the driver module. Then
 759    exit minicom.  I expect an "oops".  -- REW */
 760
 761 static void scc_hungup(void *ptr)
 762 {
 763         scc_disable_tx_interrupts(ptr);
 764         scc_disable_rx_interrupts(ptr);
 765 }
 766
 767
 768 static void scc_close(void *ptr)
 769 {
 770         scc_disable_tx_interrupts(ptr);
 771         scc_disable_rx_interrupts(ptr);
 772 }
 773
 774
 775 /*---------------------------------------------------------------------------
 776  * Internal support functions
 777  *--------------------------------------------------------------------------*/
 778
 779 static void scc_setsignals(struct scc_port *port, int dtr, int rts)
 780 {
 781         unsigned long flags;
 782         unsigned char t;
 783         SCC_ACCESS_INIT(port);
 784
 785         local_irq_save(flags);
 786         t = SCCread(TX_CTRL_REG);
 787         if (dtr >= 0) t = dtr? (t | TCR_DTR): (t & ~TCR_DTR);
 788         if (rts >= 0) t = rts? (t | TCR_RTS): (t & ~TCR_RTS);
 789         SCCwrite(TX_CTRL_REG, t);
 790         local_irq_restore(flags);
 791 }
 792
 793
 794 static void scc_send_xchar(struct tty_struct *tty, char ch)
 795 {
 796         struct scc_port *port = (struct scc_port *)tty->driver_data;
 797
 798         port->x_char = ch;
 799         if (ch)
 800                 scc_enable_tx_interrupts(port);
 801 }
 802
 803
 804 /*---------------------------------------------------------------------------
 805  * Driver entrypoints referenced from above
 806  *--------------------------------------------------------------------------*/
 807
 808 static int scc_open (struct tty_struct * tty, struct file * filp)
 809 {
 810         int line = tty->index;
 811         int retval;
 812         struct scc_port *port = &scc_ports[line];
 813         int i, channel = port->channel;
 814         unsigned long   flags;
 815         SCC_ACCESS_INIT(port);
 816 #if defined(CONFIG_MVME162_SCC) || defined(CONFIG_MVME147_SCC)
 817         static const struct {
 818                 unsigned reg, val;
 819         } mvme_init_tab[] = {
 820                 /* Values for MVME162 and MVME147 */
 821                 /* no parity, 1 stop bit, async, 1:16 */
 822                 { AUX1_CTRL_REG, A1CR_PARITY_NONE|A1CR_MODE_ASYNC_1|A1CR_CLKMODE_x16 },
 823                 /* parity error is special cond, ints disabled, no DMA */
 824                 { INT_AND_DMA_REG, IDR_PARERR_AS_SPCOND | IDR_RX_INT_DISAB },
 825                 /* Rx 8 bits/char, no auto enable, Rx off */
 826                 { RX_CTRL_REG, RCR_CHSIZE_8 },
 827                 /* DTR off, Tx 8 bits/char, RTS off, Tx off */
 828                 { TX_CTRL_REG, TCR_CHSIZE_8 },
 829                 /* special features off */
 830                 { AUX2_CTRL_REG, 0 },
 831                 { CLK_CTRL_REG, CCR_RXCLK_BRG | CCR_TXCLK_BRG },
 832                 { DPLL_CTRL_REG, DCR_BRG_ENAB | DCR_BRG_USE_PCLK },
 833                 /* Start Rx */
 834                 { RX_CTRL_REG, RCR_RX_ENAB | RCR_CHSIZE_8 },
 835                 /* Start Tx */
 836                 { TX_CTRL_REG, TCR_TX_ENAB | TCR_RTS | TCR_DTR | TCR_CHSIZE_8 },
 837                 /* Ext/Stat ints: DCD only */
 838                 { INT_CTRL_REG, ICR_ENAB_DCD_INT },
 839                 /* Reset Ext/Stat ints */
 840                 { COMMAND_REG, CR_EXTSTAT_RESET },
 841                 /* ...again */
 842                 { COMMAND_REG, CR_EXTSTAT_RESET },
 843         };
 844 #endif
 845 #if defined(CONFIG_BVME6000_SCC)
 846         static const struct {
 847                 unsigned reg, val;
 848         } bvme_init_tab[] = {
 849                 /* Values for BVME6000 */
 850                 /* no parity, 1 stop bit, async, 1:16 */
 851                 { AUX1_CTRL_REG, A1CR_PARITY_NONE|A1CR_MODE_ASYNC_1|A1CR_CLKMODE_x16 },
 852                 /* parity error is special cond, ints disabled, no DMA */
 853                 { INT_AND_DMA_REG, IDR_PARERR_AS_SPCOND | IDR_RX_INT_DISAB },
 854                 /* Rx 8 bits/char, no auto enable, Rx off */
 855                 { RX_CTRL_REG, RCR_CHSIZE_8 },
 856                 /* DTR off, Tx 8 bits/char, RTS off, Tx off */
 857                 { TX_CTRL_REG, TCR_CHSIZE_8 },
 858                 /* special features off */
 859                 { AUX2_CTRL_REG, 0 },
 860                 { CLK_CTRL_REG, CCR_RTxC_XTAL | CCR_RXCLK_BRG | CCR_TXCLK_BRG },
 861                 { DPLL_CTRL_REG, DCR_BRG_ENAB },
 862                 /* Start Rx */
 863                 { RX_CTRL_REG, RCR_RX_ENAB | RCR_CHSIZE_8 },
 864                 /* Start Tx */
 865                 { TX_CTRL_REG, TCR_TX_ENAB | TCR_RTS | TCR_DTR | TCR_CHSIZE_8 },
 866                 /* Ext/Stat ints: DCD only */
 867                 { INT_CTRL_REG, ICR_ENAB_DCD_INT },
 868                 /* Reset Ext/Stat ints */
 869                 { COMMAND_REG, CR_EXTSTAT_RESET },
 870                 /* ...again */
 871                 { COMMAND_REG, CR_EXTSTAT_RESET },
 872         };
 873 #endif
 874         if (!(port->gs.flags & ASYNC_INITIALIZED)) {
 875                 local_irq_save(flags);
 876 #if defined(CONFIG_MVME147_SCC) || defined(CONFIG_MVME162_SCC)
 877                 if (MACH_IS_MVME147 || MACH_IS_MVME16x) {
 878                         for (i=0; i<sizeof(mvme_init_tab)/sizeof(*mvme_init_tab); ++i)
 879                                 SCCwrite(mvme_init_tab[i].reg, mvme_init_tab[i].val);
 880                 }
 881 #endif
 882 #if defined(CONFIG_BVME6000_SCC)
 883                 if (MACH_IS_BVME6000) {
 884                         for (i=0; i<sizeof(bvme_init_tab)/sizeof(*bvme_init_tab); ++i)
 885                                 SCCwrite(bvme_init_tab[i].reg, bvme_init_tab[i].val);
 886                 }
 887 #endif
 888
 889                 /* remember status register for detection of DCD and CTS changes */
 890                 scc_last_status_reg[channel] = SCCread(STATUS_REG);
 891
 892                 port->c_dcd = 0;        /* Prevent initial 1->0 interrupt */
 893                 scc_setsignals (port, 1,1);
 894                 local_irq_restore(flags);
 895         }
 896
 897         tty->driver_data = port;
 898         port->gs.tty = tty;
 899         port->gs.count++;
 900         retval = gs_init_port(&port->gs);
 901         if (retval) {
 902                 port->gs.count--;
 903                 return retval;
 904         }
 905         port->gs.flags |= GS_ACTIVE;
 906         retval = gs_block_til_ready(port, filp);
 907
 908         if (retval) {
 909                 port->gs.count--;
 910                 return retval;
 911         }
 912
 913         port->c_dcd = scc_get_CD (port);
 914
 915         scc_enable_rx_interrupts(port);
 916
 917         return 0;
 918 }
 919
 920
 921 static void scc_throttle (struct tty_struct * tty)
 922 {
 923         struct scc_port *port = (struct scc_port *)tty->driver_data;
 924         unsigned long   flags;
 925         SCC_ACCESS_INIT(port);
 926
 927         if (tty->termios->c_cflag & CRTSCTS) {
 928                 local_irq_save(flags);
 929                 SCCmod(TX_CTRL_REG, ~TCR_RTS, 0);
 930                 local_irq_restore(flags);
 931         }
 932         if (I_IXOFF(tty))
 933                 scc_send_xchar(tty, STOP_CHAR(tty));
 934 }
 935
 936
 937 static void scc_unthrottle (struct tty_struct * tty)
 938 {
 939         struct scc_port *port = (struct scc_port *)tty->driver_data;
 940         unsigned long   flags;
 941         SCC_ACCESS_INIT(port);
 942
 943         if (tty->termios->c_cflag & CRTSCTS) {
 944                 local_irq_save(flags);
 945                 SCCmod(TX_CTRL_REG, 0xff, TCR_RTS);
 946                 local_irq_restore(flags);
 947         }
 948         if (I_IXOFF(tty))
 949                 scc_send_xchar(tty, START_CHAR(tty));
 950 }
 951
 952
 953 static int scc_ioctl(struct tty_struct *tty, struct file *file,
 954                      unsigned int cmd, unsigned long arg)
 955 {
 956         return -ENOIOCTLCMD;
 957 }
 958
 959
 960 static void scc_break_ctl(struct tty_struct *tty, int break_state)
 961 {
 962         struct scc_port *port = (struct scc_port *)tty->driver_data;
 963         unsigned long   flags;
 964         SCC_ACCESS_INIT(port);
 965
 966         local_irq_save(flags);
 967         SCCmod(TX_CTRL_REG, ~TCR_SEND_BREAK,
 968                         break_state ? TCR_SEND_BREAK : 0);
 969         local_irq_restore(flags);
 970 }
 971
 972
 973 /*---------------------------------------------------------------------------
 974  * Serial console stuff...
 975  *--------------------------------------------------------------------------*/
 976
 977 #define scc_delay() do { __asm__ __volatile__ (" nop; nop"); } while (0)
 978
 979 static void scc_ch_write (char ch)
 980 {
 981         volatile char *p = NULL;
 982
 983 #ifdef CONFIG_MVME147_SCC
 984         if (MACH_IS_MVME147)
 985                 p = (volatile char *)M147_SCC_A_ADDR;
 986 #endif
 987 #ifdef CONFIG_MVME162_SCC
 988         if (MACH_IS_MVME16x)
 989                 p = (volatile char *)MVME_SCC_A_ADDR;
 990 #endif
 991 #ifdef CONFIG_BVME6000_SCC
 992         if (MACH_IS_BVME6000)
 993                 p = (volatile char *)BVME_SCC_A_ADDR;
 994 #endif
 995
 996         do {
 997                 scc_delay();
 998         }
 999         while (!(*p & 4));
1000         scc_delay();
1001         *p = 8;
1002         scc_delay();
1003         *p = ch;
1004 }
1005
1006 /* The console must be locked when we get here. */
1007
1008 static void scc_console_write (struct console *co, const char *str, unsigned count)
1009 {
1010         unsigned long   flags;
1011
1012         local_irq_save(flags);
1013
1014         while (count--)
1015         {
1016                 if (*str == '\n')
1017                         scc_ch_write ('\r');
1018                 scc_ch_write (*str++);
1019         }
1020         local_irq_restore(flags);
1021 }
1022
1023 static struct tty_driver *scc_console_device(struct console *c, int *index)
1024 {
1025         *index = c->index;
1026         return scc_driver;
1027 }
1028
1029
1030 static int __init scc_console_setup(struct console *co, char *options)
1031 {
1032         return 0;
1033 }
1034
1035
1036 static struct console sercons = {
1037         .name           = "ttyS",
1038         .write          = scc_console_write,
1039         .device         = scc_console_device,
1040         .setup          = scc_console_setup,
1041         .flags          = CON_PRINTBUFFER,
1042         .index          = -1,
1043 };
1044
1045
1046 static int __init vme_scc_console_init(void)
1047 {
1048         if (vme_brdtype == VME_TYPE_MVME147 ||
1049                         vme_brdtype == VME_TYPE_MVME162 ||
1050                         vme_brdtype == VME_TYPE_MVME172 ||
1051                         vme_brdtype == VME_TYPE_BVME4000 ||
1052                         vme_brdtype == VME_TYPE_BVME6000)
1053                 register_console(&sercons);
1054         return 0;
1055 }
1056 console_initcall(vme_scc_console_init);