LXR linux/drivers/tty/serial/8250/8250

   1/*
   2 * Driver for the 98626/98644/internal serial interface on hp300/hp400
   3 * (based on the National Semiconductor INS8250/NS16550AF/WD16C552 UARTs)
   4 *
   5 * Ported from 2.2 and modified to use the normal 8250 driver
   6 * by Kars de Jong <jongk@linux-m68k.org>, May 2004.
   7 */
   8#include <linux/module.h>
   9#include <linux/init.h>
  10#include <linux/string.h>
  11#include <linux/kernel.h>
  12#include <linux/serial.h>
  13#include <linux/serial_8250.h>
  14#include <linux/delay.h>
  15#include <linux/dio.h>
  16#include <linux/console.h>
  17#include <linux/slab.h>
  18#include <asm/io.h>
  19
  20#include "8250.h"
  21
  22#if !defined(CONFIG_HPDCA) && !defined(CONFIG_HPAPCI)
  23#warning CONFIG_SERIAL_8250 defined but neither CONFIG_HPDCA nor CONFIG_HPAPCI defined, are you sure?
  24#endif
  25
  26#ifdef CONFIG_HPAPCI
  27struct hp300_port {
  28        struct hp300_port *next;        /* next port */
  29        int line;                       /* line (tty) number */
  30};
  31
  32static struct hp300_port *hp300_ports;
  33#endif
  34
  35#ifdef CONFIG_HPDCA
  36
  37static int hpdca_init_one(struct dio_dev *d,
  38                                        const struct dio_device_id *ent);
  39static void hpdca_remove_one(struct dio_dev *d);
  40
  41static struct dio_device_id hpdca_dio_tbl[] = {
  42        { DIO_ID_DCA0 },
  43        { DIO_ID_DCA0REM },
  44        { DIO_ID_DCA1 },
  45        { DIO_ID_DCA1REM },
  46        { 0 }
  47};
  48
  49static struct dio_driver hpdca_driver = {
  50        .name      = "hpdca",
  51        .id_table  = hpdca_dio_tbl,
  52        .probe     = hpdca_init_one,
  53        .remove    = hpdca_remove_one,
  54};
  55
  56#endif
  57
  58static unsigned int num_ports;
  59
  60extern int hp300_uart_scode;
  61
  62/* Offset to UART registers from base of DCA */
  63#define UART_OFFSET     17
  64
  65#define DCA_ID          0x01    /* ID (read), reset (write) */
  66#define DCA_IC          0x03    /* Interrupt control        */
  67
  68/* Interrupt control */
  69#define DCA_IC_IE       0x80    /* Master interrupt enable  */
  70
  71#define HPDCA_BAUD_BASE 153600
  72
  73/* Base address of the Frodo part */
  74#define FRODO_BASE      (0x41c000)
  75
  76/*
  77 * Where we find the 8250-like APCI ports, and how far apart they are.
  78 */
  79#define FRODO_APCIBASE          0x0
  80#define FRODO_APCISPACE         0x20
  81#define FRODO_APCI_OFFSET(x)    (FRODO_APCIBASE + ((x) * FRODO_APCISPACE))
  82
  83#define HPAPCI_BAUD_BASE 500400
  84
  85#ifdef CONFIG_SERIAL_8250_CONSOLE
  86/*
  87 * Parse the bootinfo to find descriptions for headless console and
  88 * debug serial ports and register them with the 8250 driver.
  89 */
  90int __init hp300_setup_serial_console(void)
  91{
  92        int scode;
  93        struct uart_port port;
  94
  95        memset(&port, 0, sizeof(port));
  96
  97        if (hp300_uart_scode < 0 || hp300_uart_scode > DIO_SCMAX)
  98                return 0;
  99
 100        if (DIO_SCINHOLE(hp300_uart_scode))
 101                return 0;
 102
 103        scode = hp300_uart_scode;
 104
 105        /* Memory mapped I/O */
 106        port.iotype = UPIO_MEM;
 107        port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
 108        port.type = PORT_UNKNOWN;
 109
 110        /* Check for APCI console */
 111        if (scode == 256) {
 112#ifdef CONFIG_HPAPCI
 113                pr_info("Serial console is HP APCI 1\n");
 114
 115                port.uartclk = HPAPCI_BAUD_BASE * 16;
 116                port.mapbase = (FRODO_BASE + FRODO_APCI_OFFSET(1));
 117                port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
 118                port.regshift = 2;
 119                add_preferred_console("ttyS", port.line, "9600n8");
 120#else
 121                pr_warn("Serial console is APCI but support is disabled (CONFIG_HPAPCI)!\n");
 122                return 0;
 123#endif
 124        } else {
 125#ifdef CONFIG_HPDCA
 126                unsigned long pa = dio_scodetophysaddr(scode);
 127                if (!pa)
 128                        return 0;
 129
 130                pr_info("Serial console is HP DCA at select code %d\n", scode);
 131
 132                port.uartclk = HPDCA_BAUD_BASE * 16;
 133                port.mapbase = (pa + UART_OFFSET);
 134                port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
 135                port.regshift = 1;
 136                port.irq = DIO_IPL(pa + DIO_VIRADDRBASE);
 137
 138                /* Enable board-interrupts */
 139                out_8(pa + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
 140
 141                if (DIO_ID(pa + DIO_VIRADDRBASE) & 0x80)
 142                        add_preferred_console("ttyS", port.line, "9600n8");
 143#else
 144                pr_warn("Serial console is DCA but support is disabled (CONFIG_HPDCA)!\n");
 145                return 0;
 146#endif
 147        }
 148
 149        if (early_serial_setup(&port) < 0)
 150                pr_warn("%s: early_serial_setup() failed.\n", __func__);
 151        return 0;
 152}
 153#endif /* CONFIG_SERIAL_8250_CONSOLE */
 154
 155#ifdef CONFIG_HPDCA
 156static int hpdca_init_one(struct dio_dev *d,
 157                                const struct dio_device_id *ent)
 158{
 159        struct uart_8250_port uart;
 160        int line;
 161
 162#ifdef CONFIG_SERIAL_8250_CONSOLE
 163        if (hp300_uart_scode == d->scode) {
 164                /* Already got it. */
 165                return 0;
 166        }
 167#endif
 168        memset(&uart, 0, sizeof(uart));
 169
 170        /* Memory mapped I/O */
 171        uart.port.iotype = UPIO_MEM;
 172        uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
 173        uart.port.irq = d->ipl;
 174        uart.port.uartclk = HPDCA_BAUD_BASE * 16;
 175        uart.port.mapbase = (d->resource.start + UART_OFFSET);
 176        uart.port.membase = (char *)(uart.port.mapbase + DIO_VIRADDRBASE);
 177        uart.port.regshift = 1;
 178        uart.port.dev = &d->dev;
 179        line = serial8250_register_8250_port(&uart);
 180
 181        if (line < 0) {
 182                dev_notice(&d->dev,
 183                          "8250_hp300: register_serial() DCA scode %d irq %d failed\n",
 184                          d->scode, uart.port.irq);
 185                return -ENOMEM;
 186        }
 187
 188        /* Enable board-interrupts */
 189        out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
 190        dio_set_drvdata(d, (void *)line);
 191
 192        /* Reset the DCA */
 193        out_8(d->resource.start + DIO_VIRADDRBASE + DCA_ID, 0xff);
 194        udelay(100);
 195
 196        num_ports++;
 197
 198        return 0;
 199}
 200#endif
 201
 202static int __init hp300_8250_init(void)
 203{
 204        static int called;
 205#ifdef CONFIG_HPAPCI
 206        int line;
 207        unsigned long base;
 208        struct uart_8250_port uart;
 209        struct hp300_port *port;
 210        int i;
 211#endif
 212        if (called)
 213                return -ENODEV;
 214        called = 1;
 215
 216        if (!MACH_IS_HP300)
 217                return -ENODEV;
 218
 219#ifdef CONFIG_HPDCA
 220        dio_register_driver(&hpdca_driver);
 221#endif
 222#ifdef CONFIG_HPAPCI
 223        if (hp300_model < HP_400) {
 224                if (!num_ports)
 225                        return -ENODEV;
 226                return 0;
 227        }
 228        /* These models have the Frodo chip.
 229         * Port 0 is reserved for the Apollo Domain keyboard.
 230         * Port 1 is either the console or the DCA.
 231         */
 232        for (i = 1; i < 4; i++) {
 233                /* Port 1 is the console on a 425e, on other machines it's
 234                 * mapped to DCA.
 235                 */
 236#ifdef CONFIG_SERIAL_8250_CONSOLE
 237                if (i == 1)
 238                        continue;
 239#endif
 240
 241                /* Create new serial device */
 242                port = kmalloc(sizeof(struct hp300_port), GFP_KERNEL);
 243                if (!port)
 244                        return -ENOMEM;
 245
 246                memset(&uart, 0, sizeof(uart));
 247
 248                base = (FRODO_BASE + FRODO_APCI_OFFSET(i));
 249
 250                /* Memory mapped I/O */
 251                uart.port.iotype = UPIO_MEM;
 252                uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ
 253                                | UPF_BOOT_AUTOCONF;
 254                /* XXX - no interrupt support yet */
 255                uart.port.irq = 0;
 256                uart.port.uartclk = HPAPCI_BAUD_BASE * 16;
 257                uart.port.mapbase = base;
 258                uart.port.membase = (char *)(base + DIO_VIRADDRBASE);
 259                uart.port.regshift = 2;
 260
 261                line = serial8250_register_8250_port(&uart);
 262
 263                if (line < 0) {
 264                        dev_notice(uart.port.dev,
 265                                   "8250_hp300: register_serial() APCI %d irq %d failed\n",
 266                                   i, uart.port.irq);
 267                        kfree(port);
 268                        continue;
 269                }
 270
 271                port->line = line;
 272                port->next = hp300_ports;
 273                hp300_ports = port;
 274
 275                num_ports++;
 276        }
 277#endif
 278
 279        /* Any boards found? */
 280        if (!num_ports)
 281                return -ENODEV;
 282
 283        return 0;
 284}
 285
 286#ifdef CONFIG_HPDCA
 287static void hpdca_remove_one(struct dio_dev *d)
 288{
 289        int line;
 290
 291        line = (int) dio_get_drvdata(d);
 292        if (d->resource.start) {
 293                /* Disable board-interrupts */
 294                out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, 0);
 295        }
 296        serial8250_unregister_port(line);
 297}
 298#endif
 299
 300static void __exit hp300_8250_exit(void)
 301{
 302#ifdef CONFIG_HPAPCI
 303        struct hp300_port *port, *to_free;
 304
 305        for (port = hp300_ports; port; ) {
 306                serial8250_unregister_port(port->line);
 307                to_free = port;
 308                port = port->next;
 309                kfree(to_free);
 310        }
 311
 312        hp300_ports = NULL;
 313#endif
 314#ifdef CONFIG_HPDCA
 315        dio_unregister_driver(&hpdca_driver);
 316#endif
 317}
 318
 319module_init(hp300_8250_init);
 320module_exit(hp300_8250_exit);
 321MODULE_DESCRIPTION("HP DCA/APCI serial driver");
 322MODULE_AUTHOR("Kars de Jong <jongk@linux-m68k.org>");
 323MODULE_LICENSE("GPL");
 324