linux/drivers/char/vme_scc.c
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   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/kdev_t.h>
  18#include <asm/io.h>
  19#include <linux/kernel.h>
  20#include <linux/ioport.h>
  21#include <linux/interrupt.h>
  22#include <linux/errno.h>
  23#include <linux/tty.h>
  24#include <linux/tty_flip.h>
  25#include <linux/mm.h>
  26#include <linux/serial.h>
  27#include <linux/fcntl.h>
  28#include <linux/major.h>
  29#include <linux/delay.h>
  30#include <linux/slab.h>
  31#include <linux/miscdevice.h>
  32#include <linux/console.h>
  33#include <linux/init.h>
  34#include <asm/setup.h>
  35#include <asm/bootinfo.h>
  36
  37#ifdef CONFIG_MVME147_SCC
  38#include <asm/mvme147hw.h>
  39#endif
  40#ifdef CONFIG_MVME162_SCC
  41#include <asm/mvme16xhw.h>
  42#endif
  43#ifdef CONFIG_BVME6000_SCC
  44#include <asm/bvme6000hw.h>
  45#endif
  46
  47#include <linux/generic_serial.h>
  48#include "scc.h"
  49
  50
  51#define CHANNEL_A       0
  52#define CHANNEL_B       1
  53
  54#define SCC_MINOR_BASE  64
  55
  56/* Shadows for all SCC write registers */
  57static unsigned char scc_shadow[2][16];
  58
  59/* Location to access for SCC register access delay */
  60static volatile unsigned char *scc_del = NULL;
  61
  62/* To keep track of STATUS_REG state for detection of Ext/Status int source */
  63static unsigned char scc_last_status_reg[2];
  64
  65/***************************** Prototypes *****************************/
  66
  67/* Function prototypes */
  68static void scc_disable_tx_interrupts(void * ptr);
  69static void scc_enable_tx_interrupts(void * ptr);
  70static void scc_disable_rx_interrupts(void * ptr);
  71static void scc_enable_rx_interrupts(void * ptr);
  72static int  scc_get_CD(void * ptr);
  73static void scc_shutdown_port(void * ptr);
  74static int scc_set_real_termios(void  *ptr);
  75static void scc_hungup(void  *ptr);
  76static void scc_close(void  *ptr);
  77static int scc_chars_in_buffer(void * ptr);
  78static int scc_open(struct tty_struct * tty, struct file * filp);
  79static int scc_ioctl(struct tty_struct * tty, struct file * filp,
  80                     unsigned int cmd, unsigned long arg);
  81static void scc_throttle(struct tty_struct *tty);
  82static void scc_unthrottle(struct tty_struct *tty);
  83static irqreturn_t scc_tx_int(int irq, void *data);
  84static irqreturn_t scc_rx_int(int irq, void *data);
  85static irqreturn_t scc_stat_int(int irq, void *data);
  86static irqreturn_t scc_spcond_int(int irq, void *data);
  87static void scc_setsignals(struct scc_port *port, int dtr, int rts);
  88static void scc_break_ctl(struct tty_struct *tty, int break_state);
  89
  90static struct tty_driver *scc_driver;
  91
  92struct scc_port scc_ports[2];
  93
  94int scc_initialized = 0;
  95
  96/*---------------------------------------------------------------------------
  97 * Interface from generic_serial.c back here
  98 *--------------------------------------------------------------------------*/
  99
 100static struct real_driver scc_real_driver = {
 101        scc_disable_tx_interrupts,
 102        scc_enable_tx_interrupts,
 103        scc_disable_rx_interrupts,
 104        scc_enable_rx_interrupts,
 105        scc_get_CD,
 106        scc_shutdown_port,
 107        scc_set_real_termios,
 108        scc_chars_in_buffer,
 109        scc_close,
 110        scc_hungup,
 111        NULL
 112};
 113
 114
 115static const struct tty_operations scc_ops = {
 116        .open   = scc_open,
 117        .close = gs_close,
 118        .write = gs_write,
 119        .put_char = gs_put_char,
 120        .flush_chars = gs_flush_chars,
 121        .write_room = gs_write_room,
 122        .chars_in_buffer = gs_chars_in_buffer,
 123        .flush_buffer = gs_flush_buffer,
 124        .ioctl = scc_ioctl,
 125        .throttle = scc_throttle,
 126        .unthrottle = scc_unthrottle,
 127        .set_termios = gs_set_termios,
 128        .stop = gs_stop,
 129        .start = gs_start,
 130        .hangup = gs_hangup,
 131        .break_ctl = scc_break_ctl,
 132};
 133
 134/*----------------------------------------------------------------------------
 135 * vme_scc_init() and support functions
 136 *---------------------------------------------------------------------------*/
 137
 138static int scc_init_drivers(void)
 139{
 140        int error;
 141
 142        scc_driver = alloc_tty_driver(2);
 143        if (!scc_driver)
 144                return -ENOMEM;
 145        scc_driver->owner = THIS_MODULE;
 146        scc_driver->driver_name = "scc";
 147        scc_driver->name = "ttyS";
 148        scc_driver->major = TTY_MAJOR;
 149        scc_driver->minor_start = SCC_MINOR_BASE;
 150        scc_driver->type = TTY_DRIVER_TYPE_SERIAL;
 151        scc_driver->subtype = SERIAL_TYPE_NORMAL;
 152        scc_driver->init_termios = tty_std_termios;
 153        scc_driver->init_termios.c_cflag =
 154          B9600 | CS8 | CREAD | HUPCL | CLOCAL;
 155        scc_driver->init_termios.c_ispeed = 9600;
 156        scc_driver->init_termios.c_ospeed = 9600;
 157        scc_driver->flags = TTY_DRIVER_REAL_RAW;
 158        tty_set_operations(scc_driver, &scc_ops);
 159
 160        if ((error = tty_register_driver(scc_driver))) {
 161                printk(KERN_ERR "scc: Couldn't register scc driver, error = %d\n",
 162                       error);
 163                put_tty_driver(scc_driver);
 164                return 1;
 165        }
 166
 167        return 0;
 168}
 169
 170
 171/* ports[] array is indexed by line no (i.e. [0] for ttyS0, [1] for ttyS1).
 172 */
 173
 174static void scc_init_portstructs(void)
 175{
 176        struct scc_port *port;
 177        int i;
 178
 179        for (i = 0; i < 2; i++) {
 180                port = scc_ports + i;
 181                port->gs.magic = SCC_MAGIC;
 182                port->gs.close_delay = HZ/2;
 183                port->gs.closing_wait = 30 * HZ;
 184                port->gs.rd = &scc_real_driver;
 185#ifdef NEW_WRITE_LOCKING
 186                port->gs.port_write_mutex = MUTEX;
 187#endif
 188                init_waitqueue_head(&port->gs.open_wait);
 189                init_waitqueue_head(&port->gs.close_wait);
 190        }
 191}
 192
 193
 194#ifdef CONFIG_MVME147_SCC
 195static int mvme147_scc_init(void)
 196{
 197        struct scc_port *port;
 198
 199        printk(KERN_INFO "SCC: MVME147 Serial Driver\n");
 200        /* Init channel A */
 201        port = &scc_ports[0];
 202        port->channel = CHANNEL_A;
 203        port->ctrlp = (volatile unsigned char *)M147_SCC_A_ADDR;
 204        port->datap = port->ctrlp + 1;
 205        port->port_a = &scc_ports[0];
 206        port->port_b = &scc_ports[1];
 207        request_irq(MVME147_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
 208                            "SCC-A TX", port);
 209        request_irq(MVME147_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
 210                            "SCC-A status", port);
 211        request_irq(MVME147_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
 212                            "SCC-A RX", port);
 213        request_irq(MVME147_IRQ_SCCA_SPCOND, scc_spcond_int, IRQF_DISABLED,
 214                            "SCC-A special cond", port);
 215        {
 216                SCC_ACCESS_INIT(port);
 217
 218                /* disable interrupts for this channel */
 219                SCCwrite(INT_AND_DMA_REG, 0);
 220                /* Set the interrupt vector */
 221                SCCwrite(INT_VECTOR_REG, MVME147_IRQ_SCC_BASE);
 222                /* Interrupt parameters: vector includes status, status low */
 223                SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
 224                SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
 225        }
 226
 227        /* Init channel B */
 228        port = &scc_ports[1];
 229        port->channel = CHANNEL_B;
 230        port->ctrlp = (volatile unsigned char *)M147_SCC_B_ADDR;
 231        port->datap = port->ctrlp + 1;
 232        port->port_a = &scc_ports[0];
 233        port->port_b = &scc_ports[1];
 234        request_irq(MVME147_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
 235                            "SCC-B TX", port);
 236        request_irq(MVME147_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
 237                            "SCC-B status", port);
 238        request_irq(MVME147_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
 239                            "SCC-B RX", port);
 240        request_irq(MVME147_IRQ_SCCB_SPCOND, scc_spcond_int, IRQF_DISABLED,
 241                            "SCC-B special cond", port);
 242        {
 243                SCC_ACCESS_INIT(port);
 244
 245                /* disable interrupts for this channel */
 246                SCCwrite(INT_AND_DMA_REG, 0);
 247        }
 248
 249        /* Ensure interrupts are enabled in the PCC chip */
 250        m147_pcc->serial_cntrl=PCC_LEVEL_SERIAL|PCC_INT_ENAB;
 251
 252        /* Initialise the tty driver structures and register */
 253        scc_init_portstructs();
 254        scc_init_drivers();
 255
 256        return 0;
 257}
 258#endif
 259
 260
 261#ifdef CONFIG_MVME162_SCC
 262static int mvme162_scc_init(void)
 263{
 264        struct scc_port *port;
 265
 266        if (!(mvme16x_config & MVME16x_CONFIG_GOT_SCCA))
 267                return (-ENODEV);
 268
 269        printk(KERN_INFO "SCC: MVME162 Serial Driver\n");
 270        /* Init channel A */
 271        port = &scc_ports[0];
 272        port->channel = CHANNEL_A;
 273        port->ctrlp = (volatile unsigned char *)MVME_SCC_A_ADDR;
 274        port->datap = port->ctrlp + 2;
 275        port->port_a = &scc_ports[0];
 276        port->port_b = &scc_ports[1];
 277        request_irq(MVME162_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
 278                            "SCC-A TX", port);
 279        request_irq(MVME162_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
 280                            "SCC-A status", port);
 281        request_irq(MVME162_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
 282                            "SCC-A RX", port);
 283        request_irq(MVME162_IRQ_SCCA_SPCOND, scc_spcond_int, IRQF_DISABLED,
 284                            "SCC-A special cond", port);
 285        {
 286                SCC_ACCESS_INIT(port);
 287
 288                /* disable interrupts for this channel */
 289                SCCwrite(INT_AND_DMA_REG, 0);
 290                /* Set the interrupt vector */
 291                SCCwrite(INT_VECTOR_REG, MVME162_IRQ_SCC_BASE);
 292                /* Interrupt parameters: vector includes status, status low */
 293                SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
 294                SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
 295        }
 296
 297        /* Init channel B */
 298        port = &scc_ports[1];
 299        port->channel = CHANNEL_B;
 300        port->ctrlp = (volatile unsigned char *)MVME_SCC_B_ADDR;
 301        port->datap = port->ctrlp + 2;
 302        port->port_a = &scc_ports[0];
 303        port->port_b = &scc_ports[1];
 304        request_irq(MVME162_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
 305                            "SCC-B TX", port);
 306        request_irq(MVME162_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
 307                            "SCC-B status", port);
 308        request_irq(MVME162_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
 309                            "SCC-B RX", port);
 310        request_irq(MVME162_IRQ_SCCB_SPCOND, scc_spcond_int, IRQF_DISABLED,
 311                            "SCC-B special cond", port);
 312
 313        {
 314                SCC_ACCESS_INIT(port);  /* Either channel will do */
 315
 316                /* disable interrupts for this channel */
 317                SCCwrite(INT_AND_DMA_REG, 0);
 318        }
 319
 320        /* Ensure interrupts are enabled in the MC2 chip */
 321        *(volatile char *)0xfff4201d = 0x14;
 322
 323        /* Initialise the tty driver structures and register */
 324        scc_init_portstructs();
 325        scc_init_drivers();
 326
 327        return 0;
 328}
 329#endif
 330
 331
 332#ifdef CONFIG_BVME6000_SCC
 333static int bvme6000_scc_init(void)
 334{
 335        struct scc_port *port;
 336
 337        printk(KERN_INFO "SCC: BVME6000 Serial Driver\n");
 338        /* Init channel A */
 339        port = &scc_ports[0];
 340        port->channel = CHANNEL_A;
 341        port->ctrlp = (volatile unsigned char *)BVME_SCC_A_ADDR;
 342        port->datap = port->ctrlp + 4;
 343        port->port_a = &scc_ports[0];
 344        port->port_b = &scc_ports[1];
 345        request_irq(BVME_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
 346                            "SCC-A TX", port);
 347        request_irq(BVME_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
 348                            "SCC-A status", port);
 349        request_irq(BVME_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
 350                            "SCC-A RX", port);
 351        request_irq(BVME_IRQ_SCCA_SPCOND, scc_spcond_int, IRQF_DISABLED,
 352                            "SCC-A special cond", port);
 353        {
 354                SCC_ACCESS_INIT(port);
 355
 356                /* disable interrupts for this channel */
 357                SCCwrite(INT_AND_DMA_REG, 0);
 358                /* Set the interrupt vector */
 359                SCCwrite(INT_VECTOR_REG, BVME_IRQ_SCC_BASE);
 360                /* Interrupt parameters: vector includes status, status low */
 361                SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
 362                SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
 363        }
 364
 365        /* Init channel B */
 366        port = &scc_ports[1];
 367        port->channel = CHANNEL_B;
 368        port->ctrlp = (volatile unsigned char *)BVME_SCC_B_ADDR;
 369        port->datap = port->ctrlp + 4;
 370        port->port_a = &scc_ports[0];
 371        port->port_b = &scc_ports[1];
 372        request_irq(BVME_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
 373                            "SCC-B TX", port);
 374        request_irq(BVME_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
 375                            "SCC-B status", port);
 376        request_irq(BVME_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
 377                            "SCC-B RX", port);
 378        request_irq(BVME_IRQ_SCCB_SPCOND, scc_spcond_int, IRQF_DISABLED,
 379                            "SCC-B special cond", port);
 380
 381        {
 382                SCC_ACCESS_INIT(port);  /* Either channel will do */
 383
 384                /* disable interrupts for this channel */
 385                SCCwrite(INT_AND_DMA_REG, 0);
 386        }
 387
 388        /* Initialise the tty driver structures and register */
 389        scc_init_portstructs();
 390        scc_init_drivers();
 391
 392        return 0;
 393}
 394#endif
 395
 396
 397static int vme_scc_init(void)
 398{
 399        int res = -ENODEV;
 400
 401#ifdef CONFIG_MVME147_SCC
 402        if (MACH_IS_MVME147)
 403                res = mvme147_scc_init();
 404#endif
 405#ifdef CONFIG_MVME162_SCC
 406        if (MACH_IS_MVME16x)
 407                res = mvme162_scc_init();
 408#endif
 409#ifdef CONFIG_BVME6000_SCC
 410        if (MACH_IS_BVME6000)
 411                res = bvme6000_scc_init();
 412#endif
 413        return res;
 414}
 415
 416module_init(vme_scc_init);
 417
 418
 419/*---------------------------------------------------------------------------
 420 * Interrupt handlers
 421 *--------------------------------------------------------------------------*/
 422
 423static irqreturn_t scc_rx_int(int irq, void *data)
 424{
 425        unsigned char   ch;
 426        struct scc_port *port = data;
 427        struct tty_struct *tty = port->gs.tty;
 428        SCC_ACCESS_INIT(port);
 429
 430        ch = SCCread_NB(RX_DATA_REG);
 431        if (!tty) {
 432                printk(KERN_WARNING "scc_rx_int with NULL tty!\n");
 433                SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 434                return IRQ_HANDLED;
 435        }
 436        tty_insert_flip_char(tty, ch, 0);
 437
 438        /* Check if another character is already ready; in that case, the
 439         * spcond_int() function must be used, because this character may have an
 440         * error condition that isn't signalled by the interrupt vector used!
 441         */
 442        if (SCCread(INT_PENDING_REG) &
 443            (port->channel == CHANNEL_A ? IPR_A_RX : IPR_B_RX)) {
 444                scc_spcond_int (irq, data);
 445                return IRQ_HANDLED;
 446        }
 447
 448        SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 449
 450        tty_flip_buffer_push(tty);
 451        return IRQ_HANDLED;
 452}
 453
 454
 455static irqreturn_t scc_spcond_int(int irq, void *data)
 456{
 457        struct scc_port *port = data;
 458        struct tty_struct *tty = port->gs.tty;
 459        unsigned char   stat, ch, err;
 460        int             int_pending_mask = port->channel == CHANNEL_A ?
 461                                           IPR_A_RX : IPR_B_RX;
 462        SCC_ACCESS_INIT(port);
 463        
 464        if (!tty) {
 465                printk(KERN_WARNING "scc_spcond_int with NULL tty!\n");
 466                SCCwrite(COMMAND_REG, CR_ERROR_RESET);
 467                SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 468                return IRQ_HANDLED;
 469        }
 470        do {
 471                stat = SCCread(SPCOND_STATUS_REG);
 472                ch = SCCread_NB(RX_DATA_REG);
 473
 474                if (stat & SCSR_RX_OVERRUN)
 475                        err = TTY_OVERRUN;
 476                else if (stat & SCSR_PARITY_ERR)
 477                        err = TTY_PARITY;
 478                else if (stat & SCSR_CRC_FRAME_ERR)
 479                        err = TTY_FRAME;
 480                else
 481                        err = 0;
 482
 483                tty_insert_flip_char(tty, ch, err);
 484
 485                /* ++TeSche: *All* errors have to be cleared manually,
 486                 * else the condition persists for the next chars
 487                 */
 488                if (err)
 489                  SCCwrite(COMMAND_REG, CR_ERROR_RESET);
 490
 491        } while(SCCread(INT_PENDING_REG) & int_pending_mask);
 492
 493        SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 494
 495        tty_flip_buffer_push(tty);
 496        return IRQ_HANDLED;
 497}
 498
 499
 500static irqreturn_t scc_tx_int(int irq, void *data)
 501{
 502        struct scc_port *port = data;
 503        SCC_ACCESS_INIT(port);
 504
 505        if (!port->gs.tty) {
 506                printk(KERN_WARNING "scc_tx_int with NULL tty!\n");
 507                SCCmod (INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
 508                SCCwrite(COMMAND_REG, CR_TX_PENDING_RESET);
 509                SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 510                return IRQ_HANDLED;
 511        }
 512        while ((SCCread_NB(STATUS_REG) & SR_TX_BUF_EMPTY)) {
 513                if (port->x_char) {
 514                        SCCwrite(TX_DATA_REG, port->x_char);
 515                        port->x_char = 0;
 516                }
 517                else if ((port->gs.xmit_cnt <= 0) || port->gs.tty->stopped ||
 518                                port->gs.tty->hw_stopped)
 519                        break;
 520                else {
 521                        SCCwrite(TX_DATA_REG, port->gs.xmit_buf[port->gs.xmit_tail++]);
 522                        port->gs.xmit_tail = port->gs.xmit_tail & (SERIAL_XMIT_SIZE-1);
 523                        if (--port->gs.xmit_cnt <= 0)
 524                                break;
 525                }
 526        }
 527        if ((port->gs.xmit_cnt <= 0) || port->gs.tty->stopped ||
 528                        port->gs.tty->hw_stopped) {
 529                /* disable tx interrupts */
 530                SCCmod (INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
 531                SCCwrite(COMMAND_REG, CR_TX_PENDING_RESET);   /* disable tx_int on next tx underrun? */
 532                port->gs.flags &= ~GS_TX_INTEN;
 533        }
 534        if (port->gs.tty && port->gs.xmit_cnt <= port->gs.wakeup_chars)
 535                tty_wakeup(port->gs.tty);
 536
 537        SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 538        return IRQ_HANDLED;
 539}
 540
 541
 542static irqreturn_t scc_stat_int(int irq, void *data)
 543{
 544        struct scc_port *port = data;
 545        unsigned channel = port->channel;
 546        unsigned char   last_sr, sr, changed;
 547        SCC_ACCESS_INIT(port);
 548
 549        last_sr = scc_last_status_reg[channel];
 550        sr = scc_last_status_reg[channel] = SCCread_NB(STATUS_REG);
 551        changed = last_sr ^ sr;
 552
 553        if (changed & SR_DCD) {
 554                port->c_dcd = !!(sr & SR_DCD);
 555                if (!(port->gs.flags & ASYNC_CHECK_CD))
 556                        ;       /* Don't report DCD changes */
 557                else if (port->c_dcd) {
 558                        wake_up_interruptible(&port->gs.open_wait);
 559                }
 560                else {
 561                        if (port->gs.tty)
 562                                tty_hangup (port->gs.tty);
 563                }
 564        }
 565        SCCwrite(COMMAND_REG, CR_EXTSTAT_RESET);
 566        SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
 567        return IRQ_HANDLED;
 568}
 569
 570
 571/*---------------------------------------------------------------------------
 572 * generic_serial.c callback funtions
 573 *--------------------------------------------------------------------------*/
 574
 575static void scc_disable_tx_interrupts(void *ptr)
 576{
 577        struct scc_port *port = ptr;
 578        unsigned long   flags;
 579        SCC_ACCESS_INIT(port);
 580
 581        local_irq_save(flags);
 582        SCCmod(INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
 583        port->gs.flags &= ~GS_TX_INTEN;
 584        local_irq_restore(flags);
 585}
 586
 587
 588static void scc_enable_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, 0xff, IDR_TX_INT_ENAB);
 596        /* restart the transmitter */
 597        scc_tx_int (0, port);
 598        local_irq_restore(flags);
 599}
 600
 601
 602static void scc_disable_rx_interrupts(void *ptr)
 603{
 604        struct scc_port *port = ptr;
 605        unsigned long   flags;
 606        SCC_ACCESS_INIT(port);
 607
 608        local_irq_save(flags);
 609        SCCmod(INT_AND_DMA_REG,
 610            ~(IDR_RX_INT_MASK|IDR_PARERR_AS_SPCOND|IDR_EXTSTAT_INT_ENAB), 0);
 611        local_irq_restore(flags);
 612}
 613
 614
 615static void scc_enable_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, 0xff,
 623                IDR_EXTSTAT_INT_ENAB|IDR_PARERR_AS_SPCOND|IDR_RX_INT_ALL);
 624        local_irq_restore(flags);
 625}
 626
 627
 628static int scc_get_CD(void *ptr)
 629{
 630        struct scc_port *port = ptr;
 631        unsigned channel = port->channel;
 632
 633        return !!(scc_last_status_reg[channel] & SR_DCD);
 634}
 635
 636
 637static void scc_shutdown_port(void *ptr)
 638{
 639        struct scc_port *port = ptr;
 640
 641        port->gs.flags &= ~ GS_ACTIVE;
 642        if (port->gs.tty && port->gs.tty->termios->c_cflag & HUPCL) {
 643                scc_setsignals (port, 0, 0);
 644        }
 645}
 646
 647
 648static int scc_set_real_termios (void *ptr)
 649{
 650        /* the SCC has char sizes 5,7,6,8 in that order! */
 651        static int chsize_map[4] = { 0, 2, 1, 3 };
 652        unsigned cflag, baud, chsize, channel, brgval = 0;
 653        unsigned long flags;
 654        struct scc_port *port = ptr;
 655        SCC_ACCESS_INIT(port);
 656
 657        if (!port->gs.tty || !port->gs.tty->termios) return 0;
 658
 659        channel = port->channel;
 660
 661        if (channel == CHANNEL_A)
 662                return 0;               /* Settings controlled by boot PROM */
 663
 664        cflag  = port->gs.tty->termios->c_cflag;
 665        baud = port->gs.baud;
 666        chsize = (cflag & CSIZE) >> 4;
 667
 668        if (baud == 0) {
 669                /* speed == 0 -> drop DTR */
 670                local_irq_save(flags);
 671                SCCmod(TX_CTRL_REG, ~TCR_DTR, 0);
 672                local_irq_restore(flags);
 673                return 0;
 674        }
 675        else if ((MACH_IS_MVME16x && (baud < 50 || baud > 38400)) ||
 676                 (MACH_IS_MVME147 && (baud < 50 || baud > 19200)) ||
 677                 (MACH_IS_BVME6000 &&(baud < 50 || baud > 76800))) {
 678                printk(KERN_NOTICE "SCC: Bad speed requested, %d\n", baud);
 679                return 0;
 680        }
 681
 682        if (cflag & CLOCAL)
 683                port->gs.flags &= ~ASYNC_CHECK_CD;
 684        else
 685                port->gs.flags |= ASYNC_CHECK_CD;
 686
 687#ifdef CONFIG_MVME147_SCC
 688        if (MACH_IS_MVME147)
 689                brgval = (M147_SCC_PCLK + baud/2) / (16 * 2 * baud) - 2;
 690#endif
 691#ifdef CONFIG_MVME162_SCC
 692        if (MACH_IS_MVME16x)
 693                brgval = (MVME_SCC_PCLK + baud/2) / (16 * 2 * baud) - 2;
 694#endif
 695#ifdef CONFIG_BVME6000_SCC
 696        if (MACH_IS_BVME6000)
 697                brgval = (BVME_SCC_RTxC + baud/2) / (16 * 2 * baud) - 2;
 698#endif
 699        /* Now we have all parameters and can go to set them: */
 700        local_irq_save(flags);
 701
 702        /* receiver's character size and auto-enables */
 703        SCCmod(RX_CTRL_REG, ~(RCR_CHSIZE_MASK|RCR_AUTO_ENAB_MODE),
 704                        (chsize_map[chsize] << 6) |
 705                        ((cflag & CRTSCTS) ? RCR_AUTO_ENAB_MODE : 0));
 706        /* parity and stop bits (both, Tx and Rx), clock mode never changes */
 707        SCCmod (AUX1_CTRL_REG,
 708                ~(A1CR_PARITY_MASK | A1CR_MODE_MASK),
 709                ((cflag & PARENB
 710                  ? (cflag & PARODD ? A1CR_PARITY_ODD : A1CR_PARITY_EVEN)
 711                  : A1CR_PARITY_NONE)
 712                 | (cflag & CSTOPB ? A1CR_MODE_ASYNC_2 : A1CR_MODE_ASYNC_1)));
 713        /* sender's character size, set DTR for valid baud rate */
 714        SCCmod(TX_CTRL_REG, ~TCR_CHSIZE_MASK, chsize_map[chsize] << 5 | TCR_DTR);
 715        /* clock sources never change */
 716        /* disable BRG before changing the value */
 717        SCCmod(DPLL_CTRL_REG, ~DCR_BRG_ENAB, 0);
 718        /* BRG value */
 719        SCCwrite(TIMER_LOW_REG, brgval & 0xff);
 720        SCCwrite(TIMER_HIGH_REG, (brgval >> 8) & 0xff);
 721        /* BRG enable, and clock source never changes */
 722        SCCmod(DPLL_CTRL_REG, 0xff, DCR_BRG_ENAB);
 723
 724        local_irq_restore(flags);
 725
 726        return 0;
 727}
 728
 729
 730static int scc_chars_in_buffer (void *ptr)
 731{
 732        struct scc_port *port = ptr;
 733        SCC_ACCESS_INIT(port);
 734
 735        return (SCCread (SPCOND_STATUS_REG) & SCSR_ALL_SENT) ? 0  : 1;
 736}
 737
 738
 739/* Comment taken from sx.c (2.4.0):
 740   I haven't the foggiest why the decrement use count has to happen
 741   here. The whole linux serial drivers stuff needs to be redesigned.
 742   My guess is that this is a hack to minimize the impact of a bug
 743   elsewhere. Thinking about it some more. (try it sometime) Try
 744   running minicom on a serial port that is driven by a modularized
 745   driver. Have the modem hangup. Then remove the driver module. Then
 746   exit minicom.  I expect an "oops".  -- REW */
 747
 748static void scc_hungup(void *ptr)
 749{
 750        scc_disable_tx_interrupts(ptr);
 751        scc_disable_rx_interrupts(ptr);
 752}
 753
 754
 755static void scc_close(void *ptr)
 756{
 757        scc_disable_tx_interrupts(ptr);
 758        scc_disable_rx_interrupts(ptr);
 759}
 760
 761
 762/*---------------------------------------------------------------------------
 763 * Internal support functions
 764 *--------------------------------------------------------------------------*/
 765
 766static void scc_setsignals(struct scc_port *port, int dtr, int rts)
 767{
 768        unsigned long flags;
 769        unsigned char t;
 770        SCC_ACCESS_INIT(port);
 771
 772        local_irq_save(flags);
 773        t = SCCread(TX_CTRL_REG);
 774        if (dtr >= 0) t = dtr? (t | TCR_DTR): (t & ~TCR_DTR);
 775        if (rts >= 0) t = rts? (t | TCR_RTS): (t & ~TCR_RTS);
 776        SCCwrite(TX_CTRL_REG, t);
 777        local_irq_restore(flags);
 778}
 779
 780
 781static void scc_send_xchar(struct tty_struct *tty, char ch)
 782{
 783        struct scc_port *port = (struct scc_port *)tty->driver_data;
 784
 785        port->x_char = ch;
 786        if (ch)
 787                scc_enable_tx_interrupts(port);
 788}
 789
 790
 791/*---------------------------------------------------------------------------
 792 * Driver entrypoints referenced from above
 793 *--------------------------------------------------------------------------*/
 794
 795static int scc_open (struct tty_struct * tty, struct file * filp)
 796{
 797        int line = tty->index;
 798        int retval;
 799        struct scc_port *port = &scc_ports[line];
 800        int i, channel = port->channel;
 801        unsigned long   flags;
 802        SCC_ACCESS_INIT(port);
 803#if defined(CONFIG_MVME162_SCC) || defined(CONFIG_MVME147_SCC)
 804        static const struct {
 805                unsigned reg, val;
 806        } mvme_init_tab[] = {
 807                /* Values for MVME162 and MVME147 */
 808                /* no parity, 1 stop bit, async, 1:16 */
 809                { AUX1_CTRL_REG, A1CR_PARITY_NONE|A1CR_MODE_ASYNC_1|A1CR_CLKMODE_x16 },
 810                /* parity error is special cond, ints disabled, no DMA */
 811                { INT_AND_DMA_REG, IDR_PARERR_AS_SPCOND | IDR_RX_INT_DISAB },
 812                /* Rx 8 bits/char, no auto enable, Rx off */
 813                { RX_CTRL_REG, RCR_CHSIZE_8 },
 814                /* DTR off, Tx 8 bits/char, RTS off, Tx off */
 815                { TX_CTRL_REG, TCR_CHSIZE_8 },
 816                /* special features off */
 817                { AUX2_CTRL_REG, 0 },
 818                { CLK_CTRL_REG, CCR_RXCLK_BRG | CCR_TXCLK_BRG },
 819                { DPLL_CTRL_REG, DCR_BRG_ENAB | DCR_BRG_USE_PCLK },
 820                /* Start Rx */
 821                { RX_CTRL_REG, RCR_RX_ENAB | RCR_CHSIZE_8 },
 822                /* Start Tx */
 823                { TX_CTRL_REG, TCR_TX_ENAB | TCR_RTS | TCR_DTR | TCR_CHSIZE_8 },
 824                /* Ext/Stat ints: DCD only */
 825                { INT_CTRL_REG, ICR_ENAB_DCD_INT },
 826                /* Reset Ext/Stat ints */
 827                { COMMAND_REG, CR_EXTSTAT_RESET },
 828                /* ...again */
 829                { COMMAND_REG, CR_EXTSTAT_RESET },
 830        };
 831#endif
 832#if defined(CONFIG_BVME6000_SCC)
 833        static const struct {
 834                unsigned reg, val;
 835        } bvme_init_tab[] = {
 836                /* Values for BVME6000 */
 837                /* no parity, 1 stop bit, async, 1:16 */
 838                { AUX1_CTRL_REG, A1CR_PARITY_NONE|A1CR_MODE_ASYNC_1|A1CR_CLKMODE_x16 },
 839                /* parity error is special cond, ints disabled, no DMA */
 840                { INT_AND_DMA_REG, IDR_PARERR_AS_SPCOND | IDR_RX_INT_DISAB },
 841                /* Rx 8 bits/char, no auto enable, Rx off */
 842                { RX_CTRL_REG, RCR_CHSIZE_8 },
 843                /* DTR off, Tx 8 bits/char, RTS off, Tx off */
 844                { TX_CTRL_REG, TCR_CHSIZE_8 },
 845                /* special features off */
 846                { AUX2_CTRL_REG, 0 },
 847                { CLK_CTRL_REG, CCR_RTxC_XTAL | CCR_RXCLK_BRG | CCR_TXCLK_BRG },
 848                { DPLL_CTRL_REG, DCR_BRG_ENAB },
 849                /* Start Rx */
 850                { RX_CTRL_REG, RCR_RX_ENAB | RCR_CHSIZE_8 },
 851                /* Start Tx */
 852                { TX_CTRL_REG, TCR_TX_ENAB | TCR_RTS | TCR_DTR | TCR_CHSIZE_8 },
 853                /* Ext/Stat ints: DCD only */
 854                { INT_CTRL_REG, ICR_ENAB_DCD_INT },
 855                /* Reset Ext/Stat ints */
 856                { COMMAND_REG, CR_EXTSTAT_RESET },
 857                /* ...again */
 858                { COMMAND_REG, CR_EXTSTAT_RESET },
 859        };
 860#endif
 861        if (!(port->gs.flags & ASYNC_INITIALIZED)) {
 862                local_irq_save(flags);
 863#if defined(CONFIG_MVME147_SCC) || defined(CONFIG_MVME162_SCC)
 864                if (MACH_IS_MVME147 || MACH_IS_MVME16x) {
 865                        for (i = 0; i < ARRAY_SIZE(mvme_init_tab); ++i)
 866                                SCCwrite(mvme_init_tab[i].reg, mvme_init_tab[i].val);
 867                }
 868#endif
 869#if defined(CONFIG_BVME6000_SCC)
 870                if (MACH_IS_BVME6000) {
 871                        for (i = 0; i < ARRAY_SIZE(bvme_init_tab); ++i)
 872                                SCCwrite(bvme_init_tab[i].reg, bvme_init_tab[i].val);
 873                }
 874#endif
 875
 876                /* remember status register for detection of DCD and CTS changes */
 877                scc_last_status_reg[channel] = SCCread(STATUS_REG);
 878
 879                port->c_dcd = 0;        /* Prevent initial 1->0 interrupt */
 880                scc_setsignals (port, 1,1);
 881                local_irq_restore(flags);
 882        }
 883
 884        tty->driver_data = port;
 885        port->gs.tty = tty;
 886        port->gs.count++;
 887        retval = gs_init_port(&port->gs);
 888        if (retval) {
 889                port->gs.count--;
 890                return retval;
 891        }
 892        port->gs.flags |= GS_ACTIVE;
 893        retval = gs_block_til_ready(port, filp);
 894
 895        if (retval) {
 896                port->gs.count--;
 897                return retval;
 898        }
 899
 900        port->c_dcd = scc_get_CD (port);
 901
 902        scc_enable_rx_interrupts(port);
 903
 904        return 0;
 905}
 906
 907
 908static void scc_throttle (struct tty_struct * tty)
 909{
 910        struct scc_port *port = (struct scc_port *)tty->driver_data;
 911        unsigned long   flags;
 912        SCC_ACCESS_INIT(port);
 913
 914        if (tty->termios->c_cflag & CRTSCTS) {
 915                local_irq_save(flags);
 916                SCCmod(TX_CTRL_REG, ~TCR_RTS, 0);
 917                local_irq_restore(flags);
 918        }
 919        if (I_IXOFF(tty))
 920                scc_send_xchar(tty, STOP_CHAR(tty));
 921}
 922
 923
 924static void scc_unthrottle (struct tty_struct * tty)
 925{
 926        struct scc_port *port = (struct scc_port *)tty->driver_data;
 927        unsigned long   flags;
 928        SCC_ACCESS_INIT(port);
 929
 930        if (tty->termios->c_cflag & CRTSCTS) {
 931                local_irq_save(flags);
 932                SCCmod(TX_CTRL_REG, 0xff, TCR_RTS);
 933                local_irq_restore(flags);
 934        }
 935        if (I_IXOFF(tty))
 936                scc_send_xchar(tty, START_CHAR(tty));
 937}
 938
 939
 940static int scc_ioctl(struct tty_struct *tty, struct file *file,
 941                     unsigned int cmd, unsigned long arg)
 942{
 943        return -ENOIOCTLCMD;
 944}
 945
 946
 947static void scc_break_ctl(struct tty_struct *tty, int break_state)
 948{
 949        struct scc_port *port = (struct scc_port *)tty->driver_data;
 950        unsigned long   flags;
 951        SCC_ACCESS_INIT(port);
 952
 953        local_irq_save(flags);
 954        SCCmod(TX_CTRL_REG, ~TCR_SEND_BREAK, 
 955                        break_state ? TCR_SEND_BREAK : 0);
 956        local_irq_restore(flags);
 957}
 958
 959
 960/*---------------------------------------------------------------------------
 961 * Serial console stuff...
 962 *--------------------------------------------------------------------------*/
 963
 964#define scc_delay() do { __asm__ __volatile__ (" nop; nop"); } while (0)
 965
 966static void scc_ch_write (char ch)
 967{
 968        volatile char *p = NULL;
 969        
 970#ifdef CONFIG_MVME147_SCC
 971        if (MACH_IS_MVME147)
 972                p = (volatile char *)M147_SCC_A_ADDR;
 973#endif
 974#ifdef CONFIG_MVME162_SCC
 975        if (MACH_IS_MVME16x)
 976                p = (volatile char *)MVME_SCC_A_ADDR;
 977#endif
 978#ifdef CONFIG_BVME6000_SCC
 979        if (MACH_IS_BVME6000)
 980                p = (volatile char *)BVME_SCC_A_ADDR;
 981#endif
 982
 983        do {
 984                scc_delay();
 985        }
 986        while (!(*p & 4));
 987        scc_delay();
 988        *p = 8;
 989        scc_delay();
 990        *p = ch;
 991}
 992
 993/* The console must be locked when we get here. */
 994
 995static void scc_console_write (struct console *co, const char *str, unsigned count)
 996{
 997        unsigned long   flags;
 998
 999        local_irq_save(flags);
1000
1001        while (count--)
1002        {
1003                if (*str == '\n')
1004                        scc_ch_write ('\r');
1005                scc_ch_write (*str++);
1006        }
1007        local_irq_restore(flags);
1008}
1009
1010static struct tty_driver *scc_console_device(struct console *c, int *index)
1011{
1012        *index = c->index;
1013        return scc_driver;
1014}
1015
1016static struct console sercons = {
1017        .name           = "ttyS",
1018        .write          = scc_console_write,
1019        .device         = scc_console_device,
1020        .flags          = CON_PRINTBUFFER,
1021        .index          = -1,
1022};
1023
1024
1025static int __init vme_scc_console_init(void)
1026{
1027        if (vme_brdtype == VME_TYPE_MVME147 ||
1028                        vme_brdtype == VME_TYPE_MVME162 ||
1029                        vme_brdtype == VME_TYPE_MVME172 ||
1030                        vme_brdtype == VME_TYPE_BVME4000 ||
1031                        vme_brdtype == VME_TYPE_BVME6000)
1032                register_console(&sercons);
1033        return 0;
1034}
1035console_initcall(vme_scc_console_init);
1036