LXR linux/drivers/net/wan/c101.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Moxa C101 synchronous serial card driver for Linux
   4 *
   5 * Copyright (C) 2000-2003 Krzysztof Halasa <khc@pm.waw.pl>
   6 *
   7 * For information see <https://www.kernel.org/pub/linux/utils/net/hdlc/>
   8 *
   9 * Sources of information:
  10 *    Hitachi HD64570 SCA User's Manual
  11 *    Moxa C101 User's Manual
  12 */
  13
  14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16#include <linux/module.h>
  17#include <linux/kernel.h>
  18#include <linux/capability.h>
  19#include <linux/slab.h>
  20#include <linux/types.h>
  21#include <linux/string.h>
  22#include <linux/errno.h>
  23#include <linux/init.h>
  24#include <linux/netdevice.h>
  25#include <linux/hdlc.h>
  26#include <linux/delay.h>
  27#include <asm/io.h>
  28
  29#include "hd64570.h"
  30
  31
  32static const char* version = "Moxa C101 driver version: 1.15";
  33static const char* devname = "C101";
  34
  35#undef DEBUG_PKT
  36#define DEBUG_RINGS
  37
  38#define C101_PAGE 0x1D00
  39#define C101_DTR 0x1E00
  40#define C101_SCA 0x1F00
  41#define C101_WINDOW_SIZE 0x2000
  42#define C101_MAPPED_RAM_SIZE 0x4000
  43
  44#define RAM_SIZE (256 * 1024)
  45#define TX_RING_BUFFERS 10
  46#define RX_RING_BUFFERS ((RAM_SIZE - C101_WINDOW_SIZE) /                \
  47                         (sizeof(pkt_desc) + HDLC_MAX_MRU) - TX_RING_BUFFERS)
  48
  49#define CLOCK_BASE 9830400      /* 9.8304 MHz */
  50#define PAGE0_ALWAYS_MAPPED
  51
  52static char *hw;                /* pointer to hw=xxx command line string */
  53
  54
  55typedef struct card_s {
  56        struct net_device *dev;
  57        spinlock_t lock;        /* TX lock */
  58        u8 __iomem *win0base;   /* ISA window base address */
  59        u32 phy_winbase;        /* ISA physical base address */
  60        sync_serial_settings settings;
  61        int rxpart;             /* partial frame received, next frame invalid*/
  62        unsigned short encoding;
  63        unsigned short parity;
  64        u16 rx_ring_buffers;    /* number of buffers in a ring */
  65        u16 tx_ring_buffers;
  66        u16 buff_offset;        /* offset of first buffer of first channel */
  67        u16 rxin;               /* rx ring buffer 'in' pointer */
  68        u16 txin;               /* tx ring buffer 'in' and 'last' pointers */
  69        u16 txlast;
  70        u8 rxs, txs, tmc;       /* SCA registers */
  71        u8 irq;                 /* IRQ (3-15) */
  72        u8 page;
  73
  74        struct card_s *next_card;
  75}card_t;
  76
  77typedef card_t port_t;
  78
  79static card_t *first_card;
  80static card_t **new_card = &first_card;
  81
  82
  83#define sca_in(reg, card)          readb((card)->win0base + C101_SCA + (reg))
  84#define sca_out(value, reg, card)  writeb(value, (card)->win0base + C101_SCA + (reg))
  85#define sca_inw(reg, card)         readw((card)->win0base + C101_SCA + (reg))
  86
  87/* EDA address register must be set in EDAL, EDAH order - 8 bit ISA bus */
  88#define sca_outw(value, reg, card) do { \
  89        writeb(value & 0xFF, (card)->win0base + C101_SCA + (reg)); \
  90        writeb((value >> 8 ) & 0xFF, (card)->win0base + C101_SCA + (reg + 1));\
  91} while(0)
  92
  93#define port_to_card(port)         (port)
  94#define log_node(port)             (0)
  95#define phy_node(port)             (0)
  96#define winsize(card)              (C101_WINDOW_SIZE)
  97#define win0base(card)             ((card)->win0base)
  98#define winbase(card)              ((card)->win0base + 0x2000)
  99#define get_port(card, port)       (card)
 100static void sca_msci_intr(port_t *port);
 101
 102
 103static inline u8 sca_get_page(card_t *card)
 104{
 105        return card->page;
 106}
 107
 108static inline void openwin(card_t *card, u8 page)
 109{
 110        card->page = page;
 111        writeb(page, card->win0base + C101_PAGE);
 112}
 113
 114
 115#include "hd64570.c"
 116
 117
 118static inline void set_carrier(port_t *port)
 119{
 120        if (!(sca_in(MSCI1_OFFSET + ST3, port) & ST3_DCD))
 121                netif_carrier_on(port_to_dev(port));
 122        else
 123                netif_carrier_off(port_to_dev(port));
 124}
 125
 126
 127static void sca_msci_intr(port_t *port)
 128{
 129        u8 stat = sca_in(MSCI0_OFFSET + ST1, port); /* read MSCI ST1 status */
 130
 131        /* Reset MSCI TX underrun and CDCD (ignored) status bit */
 132        sca_out(stat & (ST1_UDRN | ST1_CDCD), MSCI0_OFFSET + ST1, port);
 133
 134        if (stat & ST1_UDRN) {
 135                /* TX Underrun error detected */
 136                port_to_dev(port)->stats.tx_errors++;
 137                port_to_dev(port)->stats.tx_fifo_errors++;
 138        }
 139
 140        stat = sca_in(MSCI1_OFFSET + ST1, port); /* read MSCI1 ST1 status */
 141        /* Reset MSCI CDCD status bit - uses ch#2 DCD input */
 142        sca_out(stat & ST1_CDCD, MSCI1_OFFSET + ST1, port);
 143
 144        if (stat & ST1_CDCD)
 145                set_carrier(port);
 146}
 147
 148
 149static void c101_set_iface(port_t *port)
 150{
 151        u8 rxs = port->rxs & CLK_BRG_MASK;
 152        u8 txs = port->txs & CLK_BRG_MASK;
 153
 154        switch(port->settings.clock_type) {
 155        case CLOCK_INT:
 156                rxs |= CLK_BRG_RX; /* TX clock */
 157                txs |= CLK_RXCLK_TX; /* BRG output */
 158                break;
 159
 160        case CLOCK_TXINT:
 161                rxs |= CLK_LINE_RX; /* RXC input */
 162                txs |= CLK_BRG_TX; /* BRG output */
 163                break;
 164
 165        case CLOCK_TXFROMRX:
 166                rxs |= CLK_LINE_RX; /* RXC input */
 167                txs |= CLK_RXCLK_TX; /* RX clock */
 168                break;
 169
 170        default:        /* EXTernal clock */
 171                rxs |= CLK_LINE_RX; /* RXC input */
 172                txs |= CLK_LINE_TX; /* TXC input */
 173        }
 174
 175        port->rxs = rxs;
 176        port->txs = txs;
 177        sca_out(rxs, MSCI1_OFFSET + RXS, port);
 178        sca_out(txs, MSCI1_OFFSET + TXS, port);
 179        sca_set_port(port);
 180}
 181
 182
 183static int c101_open(struct net_device *dev)
 184{
 185        port_t *port = dev_to_port(dev);
 186        int result;
 187
 188        result = hdlc_open(dev);
 189        if (result)
 190                return result;
 191
 192        writeb(1, port->win0base + C101_DTR);
 193        sca_out(0, MSCI1_OFFSET + CTL, port); /* RTS uses ch#2 output */
 194        sca_open(dev);
 195        /* DCD is connected to port 2 !@#$%^& - disable MSCI0 CDCD interrupt */
 196        sca_out(IE1_UDRN, MSCI0_OFFSET + IE1, port);
 197        sca_out(IE0_TXINT, MSCI0_OFFSET + IE0, port);
 198
 199        set_carrier(port);
 200
 201        /* enable MSCI1 CDCD interrupt */
 202        sca_out(IE1_CDCD, MSCI1_OFFSET + IE1, port);
 203        sca_out(IE0_RXINTA, MSCI1_OFFSET + IE0, port);
 204        sca_out(0x48, IER0, port); /* TXINT #0 and RXINT #1 */
 205        c101_set_iface(port);
 206        return 0;
 207}
 208
 209
 210static int c101_close(struct net_device *dev)
 211{
 212        port_t *port = dev_to_port(dev);
 213
 214        sca_close(dev);
 215        writeb(0, port->win0base + C101_DTR);
 216        sca_out(CTL_NORTS, MSCI1_OFFSET + CTL, port);
 217        hdlc_close(dev);
 218        return 0;
 219}
 220
 221
 222static int c101_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 223{
 224        const size_t size = sizeof(sync_serial_settings);
 225        sync_serial_settings new_line;
 226        sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
 227        port_t *port = dev_to_port(dev);
 228
 229#ifdef DEBUG_RINGS
 230        if (cmd == SIOCDEVPRIVATE) {
 231                sca_dump_rings(dev);
 232                printk(KERN_DEBUG "MSCI1: ST: %02x %02x %02x %02x\n",
 233                       sca_in(MSCI1_OFFSET + ST0, port),
 234                       sca_in(MSCI1_OFFSET + ST1, port),
 235                       sca_in(MSCI1_OFFSET + ST2, port),
 236                       sca_in(MSCI1_OFFSET + ST3, port));
 237                return 0;
 238        }
 239#endif
 240        if (cmd != SIOCWANDEV)
 241                return hdlc_ioctl(dev, ifr, cmd);
 242
 243        switch(ifr->ifr_settings.type) {
 244        case IF_GET_IFACE:
 245                ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
 246                if (ifr->ifr_settings.size < size) {
 247                        ifr->ifr_settings.size = size; /* data size wanted */
 248                        return -ENOBUFS;
 249                }
 250                if (copy_to_user(line, &port->settings, size))
 251                        return -EFAULT;
 252                return 0;
 253
 254        case IF_IFACE_SYNC_SERIAL:
 255                if(!capable(CAP_NET_ADMIN))
 256                        return -EPERM;
 257
 258                if (copy_from_user(&new_line, line, size))
 259                        return -EFAULT;
 260
 261                if (new_line.clock_type != CLOCK_EXT &&
 262                    new_line.clock_type != CLOCK_TXFROMRX &&
 263                    new_line.clock_type != CLOCK_INT &&
 264                    new_line.clock_type != CLOCK_TXINT)
 265                        return -EINVAL; /* No such clock setting */
 266
 267                if (new_line.loopback != 0 && new_line.loopback != 1)
 268                        return -EINVAL;
 269
 270                memcpy(&port->settings, &new_line, size); /* Update settings */
 271                c101_set_iface(port);
 272                return 0;
 273
 274        default:
 275                return hdlc_ioctl(dev, ifr, cmd);
 276        }
 277}
 278
 279
 280
 281static void c101_destroy_card(card_t *card)
 282{
 283        readb(card->win0base + C101_PAGE); /* Resets SCA? */
 284
 285        if (card->irq)
 286                free_irq(card->irq, card);
 287
 288        if (card->win0base) {
 289                iounmap(card->win0base);
 290                release_mem_region(card->phy_winbase, C101_MAPPED_RAM_SIZE);
 291        }
 292
 293        free_netdev(card->dev);
 294
 295        kfree(card);
 296}
 297
 298static const struct net_device_ops c101_ops = {
 299        .ndo_open       = c101_open,
 300        .ndo_stop       = c101_close,
 301        .ndo_start_xmit = hdlc_start_xmit,
 302        .ndo_do_ioctl   = c101_ioctl,
 303};
 304
 305static int __init c101_run(unsigned long irq, unsigned long winbase)
 306{
 307        struct net_device *dev;
 308        hdlc_device *hdlc;
 309        card_t *card;
 310        int result;
 311
 312        if (irq<3 || irq>15 || irq == 6) /* FIXME */ {
 313                pr_err("invalid IRQ value\n");
 314                return -ENODEV;
 315        }
 316
 317        if (winbase < 0xC0000 || winbase > 0xDFFFF || (winbase & 0x3FFF) !=0) {
 318                pr_err("invalid RAM value\n");
 319                return -ENODEV;
 320        }
 321
 322        card = kzalloc(sizeof(card_t), GFP_KERNEL);
 323        if (card == NULL)
 324                return -ENOBUFS;
 325
 326        card->dev = alloc_hdlcdev(card);
 327        if (!card->dev) {
 328                pr_err("unable to allocate memory\n");
 329                kfree(card);
 330                return -ENOBUFS;
 331        }
 332
 333        if (request_irq(irq, sca_intr, 0, devname, card)) {
 334                pr_err("could not allocate IRQ\n");
 335                c101_destroy_card(card);
 336                return -EBUSY;
 337        }
 338        card->irq = irq;
 339
 340        if (!request_mem_region(winbase, C101_MAPPED_RAM_SIZE, devname)) {
 341                pr_err("could not request RAM window\n");
 342                c101_destroy_card(card);
 343                return -EBUSY;
 344        }
 345        card->phy_winbase = winbase;
 346        card->win0base = ioremap(winbase, C101_MAPPED_RAM_SIZE);
 347        if (!card->win0base) {
 348                pr_err("could not map I/O address\n");
 349                c101_destroy_card(card);
 350                return -EFAULT;
 351        }
 352
 353        card->tx_ring_buffers = TX_RING_BUFFERS;
 354        card->rx_ring_buffers = RX_RING_BUFFERS;
 355        card->buff_offset = C101_WINDOW_SIZE; /* Bytes 1D00-1FFF reserved */
 356
 357        readb(card->win0base + C101_PAGE); /* Resets SCA? */
 358        udelay(100);
 359        writeb(0, card->win0base + C101_PAGE);
 360        writeb(0, card->win0base + C101_DTR); /* Power-up for RAM? */
 361
 362        sca_init(card, 0);
 363
 364        dev = port_to_dev(card);
 365        hdlc = dev_to_hdlc(dev);
 366
 367        spin_lock_init(&card->lock);
 368        dev->irq = irq;
 369        dev->mem_start = winbase;
 370        dev->mem_end = winbase + C101_MAPPED_RAM_SIZE - 1;
 371        dev->tx_queue_len = 50;
 372        dev->netdev_ops = &c101_ops;
 373        hdlc->attach = sca_attach;
 374        hdlc->xmit = sca_xmit;
 375        card->settings.clock_type = CLOCK_EXT;
 376
 377        result = register_hdlc_device(dev);
 378        if (result) {
 379                pr_warn("unable to register hdlc device\n");
 380                c101_destroy_card(card);
 381                return result;
 382        }
 383
 384        sca_init_port(card); /* Set up C101 memory */
 385        set_carrier(card);
 386
 387        netdev_info(dev, "Moxa C101 on IRQ%u, using %u TX + %u RX packets rings\n",
 388                    card->irq, card->tx_ring_buffers, card->rx_ring_buffers);
 389
 390        *new_card = card;
 391        new_card = &card->next_card;
 392        return 0;
 393}
 394
 395
 396
 397static int __init c101_init(void)
 398{
 399        if (hw == NULL) {
 400#ifdef MODULE
 401                pr_info("no card initialized\n");
 402#endif
 403                return -EINVAL; /* no parameters specified, abort */
 404        }
 405
 406        pr_info("%s\n", version);
 407
 408        do {
 409                unsigned long irq, ram;
 410
 411                irq = simple_strtoul(hw, &hw, 0);
 412
 413                if (*hw++ != ',')
 414                        break;
 415                ram = simple_strtoul(hw, &hw, 0);
 416
 417                if (*hw == ':' || *hw == '\x0')
 418                        c101_run(irq, ram);
 419
 420                if (*hw == '\x0')
 421                        return first_card ? 0 : -EINVAL;
 422        }while(*hw++ == ':');
 423
 424        pr_err("invalid hardware parameters\n");
 425        return first_card ? 0 : -EINVAL;
 426}
 427
 428
 429static void __exit c101_cleanup(void)
 430{
 431        card_t *card = first_card;
 432
 433        while (card) {
 434                card_t *ptr = card;
 435                card = card->next_card;
 436                unregister_hdlc_device(port_to_dev(ptr));
 437                c101_destroy_card(ptr);
 438        }
 439}
 440
 441
 442module_init(c101_init);
 443module_exit(c101_cleanup);
 444
 445MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
 446MODULE_DESCRIPTION("Moxa C101 serial port driver");
 447MODULE_LICENSE("GPL v2");
 448module_param(hw, charp, 0444);
 449MODULE_PARM_DESC(hw, "irq,ram:irq,...");
 450