drivers/tty/serial/8250/8250_hp300.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Driver for the 98626/98644/internal serial interface on hp300/hp400
   4  * (based on the National Semiconductor INS8250/NS16550AF/WD16C552 UARTs)
   5  *
   6  * Ported from 2.2 and modified to use the normal 8250 driver
   7  * by Kars de Jong <jongk@linux-m68k.org>, May 2004.
   8  */
   9 #include <linux/module.h>
  10 #include <linux/init.h>
  11 #include <linux/string.h>
  12 #include <linux/kernel.h>
  13 #include <linux/serial.h>
  14 #include <linux/serial_8250.h>
  15 #include <linux/delay.h>
  16 #include <linux/dio.h>
  17 #include <linux/console.h>
  18 #include <linux/slab.h>
  19 #include <asm/io.h>
  20
  21 #include "8250.h"
  22
  23 #if !defined(CONFIG_HPDCA) && !defined(CONFIG_HPAPCI) && !defined(CONFIG_COMPILE_TEST)
  24 #warning CONFIG_SERIAL_8250 defined but neither CONFIG_HPDCA nor CONFIG_HPAPCI defined, are you sure?
  25 #endif
  26
  27 #ifdef CONFIG_HPAPCI
  28 struct hp300_port {
  29         struct hp300_port *next;        /* next port */
  30         int line;                       /* line (tty) number */
  31 };
  32
  33 static struct hp300_port *hp300_ports;
  34 #endif
  35
  36 #ifdef CONFIG_HPDCA
  37
  38 static int hpdca_init_one(struct dio_dev *d,
  39                                         const struct dio_device_id *ent);
  40 static void hpdca_remove_one(struct dio_dev *d);
  41
  42 static struct dio_device_id hpdca_dio_tbl[] = {
  43         { DIO_ID_DCA0 },
  44         { DIO_ID_DCA0REM },
  45         { DIO_ID_DCA1 },
  46         { DIO_ID_DCA1REM },
  47         { 0 }
  48 };
  49
  50 static struct dio_driver hpdca_driver = {
  51         .name      = "hpdca",
  52         .id_table  = hpdca_dio_tbl,
  53         .probe     = hpdca_init_one,
  54         .remove    = hpdca_remove_one,
  55 };
  56
  57 #endif
  58
  59 static unsigned int num_ports;
  60
  61 extern int hp300_uart_scode;
  62
  63 /* Offset to UART registers from base of DCA */
  64 #define UART_OFFSET     17
  65
  66 #define DCA_ID          0x01    /* ID (read), reset (write) */
  67 #define DCA_IC          0x03    /* Interrupt control        */
  68
  69 /* Interrupt control */
  70 #define DCA_IC_IE       0x80    /* Master interrupt enable  */
  71
  72 #define HPDCA_BAUD_BASE 153600
  73
  74 /* Base address of the Frodo part */
  75 #define FRODO_BASE      (0x41c000)
  76
  77 /*
  78  * Where we find the 8250-like APCI ports, and how far apart they are.
  79  */
  80 #define FRODO_APCIBASE          0x0
  81 #define FRODO_APCISPACE         0x20
  82 #define FRODO_APCI_OFFSET(x)    (FRODO_APCIBASE + ((x) * FRODO_APCISPACE))
  83
  84 #define HPAPCI_BAUD_BASE 500400
  85
  86 #ifdef CONFIG_SERIAL_8250_CONSOLE
  87 /*
  88  * Parse the bootinfo to find descriptions for headless console and
  89  * debug serial ports and register them with the 8250 driver.
  90  */
  91 int __init hp300_setup_serial_console(void)
  92 {
  93         int scode;
  94         struct uart_port port;
  95
  96         memset(&port, 0, sizeof(port));
  97
  98         if (hp300_uart_scode < 0 || hp300_uart_scode > DIO_SCMAX)
  99                 return 0;
 100
 101         if (DIO_SCINHOLE(hp300_uart_scode))
 102                 return 0;
 103
 104         scode = hp300_uart_scode;
 105
 106         /* Memory mapped I/O */
 107         port.iotype = UPIO_MEM;
 108         port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
 109         port.type = PORT_UNKNOWN;
 110
 111         /* Check for APCI console */
 112         if (scode == 256) {
 113 #ifdef CONFIG_HPAPCI
 114                 pr_info("Serial console is HP APCI 1\n");
 115
 116                 port.uartclk = HPAPCI_BAUD_BASE * 16;
 117                 port.mapbase = (FRODO_BASE + FRODO_APCI_OFFSET(1));
 118                 port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
 119                 port.regshift = 2;
 120                 add_preferred_console("ttyS", port.line, "9600n8");
 121 #else
 122                 pr_warn("Serial console is APCI but support is disabled (CONFIG_HPAPCI)!\n");
 123                 return 0;
 124 #endif
 125         } else {
 126 #ifdef CONFIG_HPDCA
 127                 unsigned long pa = dio_scodetophysaddr(scode);
 128                 if (!pa)
 129                         return 0;
 130
 131                 pr_info("Serial console is HP DCA at select code %d\n", scode);
 132
 133                 port.uartclk = HPDCA_BAUD_BASE * 16;
 134                 port.mapbase = (pa + UART_OFFSET);
 135                 port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
 136                 port.regshift = 1;
 137                 port.irq = DIO_IPL(pa + DIO_VIRADDRBASE);
 138
 139                 /* Enable board-interrupts */
 140                 out_8(pa + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
 141
 142                 if (DIO_ID(pa + DIO_VIRADDRBASE) & 0x80)
 143                         add_preferred_console("ttyS", port.line, "9600n8");
 144 #else
 145                 pr_warn("Serial console is DCA but support is disabled (CONFIG_HPDCA)!\n");
 146                 return 0;
 147 #endif
 148         }
 149
 150         if (early_serial_setup(&port) < 0)
 151                 pr_warn("%s: early_serial_setup() failed.\n", __func__);
 152         return 0;
 153 }
 154 #endif /* CONFIG_SERIAL_8250_CONSOLE */
 155
 156 #ifdef CONFIG_HPDCA
 157 static int hpdca_init_one(struct dio_dev *d,
 158                                 const struct dio_device_id *ent)
 159 {
 160         struct uart_8250_port uart;
 161         int line;
 162
 163 #ifdef CONFIG_SERIAL_8250_CONSOLE
 164         if (hp300_uart_scode == d->scode) {
 165                 /* Already got it. */
 166                 return 0;
 167         }
 168 #endif
 169         memset(&uart, 0, sizeof(uart));
 170
 171         /* Memory mapped I/O */
 172         uart.port.iotype = UPIO_MEM;
 173         uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
 174         uart.port.irq = d->ipl;
 175         uart.port.uartclk = HPDCA_BAUD_BASE * 16;
 176         uart.port.mapbase = (d->resource.start + UART_OFFSET);
 177         uart.port.membase = (char *)(uart.port.mapbase + DIO_VIRADDRBASE);
 178         uart.port.regshift = 1;
 179         uart.port.dev = &d->dev;
 180         line = serial8250_register_8250_port(&uart);
 181
 182         if (line < 0) {
 183                 dev_notice(&d->dev,
 184                           "8250_hp300: register_serial() DCA scode %d irq %d failed\n",
 185                           d->scode, uart.port.irq);
 186                 return -ENOMEM;
 187         }
 188
 189         /* Enable board-interrupts */
 190         out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
 191         dio_set_drvdata(d, (void *)line);
 192
 193         /* Reset the DCA */
 194         out_8(d->resource.start + DIO_VIRADDRBASE + DCA_ID, 0xff);
 195         udelay(100);
 196
 197         num_ports++;
 198
 199         return 0;
 200 }
 201 #endif
 202
 203 static int __init hp300_8250_init(void)
 204 {
 205         static int called;
 206 #ifdef CONFIG_HPAPCI
 207         int line;
 208         unsigned long base;
 209         struct uart_8250_port uart;
 210         struct hp300_port *port;
 211         int i;
 212 #endif
 213         if (called)
 214                 return -ENODEV;
 215         called = 1;
 216
 217         if (!MACH_IS_HP300)
 218                 return -ENODEV;
 219
 220 #ifdef CONFIG_HPDCA
 221         dio_register_driver(&hpdca_driver);
 222 #endif
 223 #ifdef CONFIG_HPAPCI
 224         if (hp300_model < HP_400) {
 225                 if (!num_ports)
 226                         return -ENODEV;
 227                 return 0;
 228         }
 229         /* These models have the Frodo chip.
 230          * Port 0 is reserved for the Apollo Domain keyboard.
 231          * Port 1 is either the console or the DCA.
 232          */
 233         for (i = 1; i < 4; i++) {
 234                 /* Port 1 is the console on a 425e, on other machines it's
 235                  * mapped to DCA.
 236                  */
 237 #ifdef CONFIG_SERIAL_8250_CONSOLE
 238                 if (i == 1)
 239                         continue;
 240 #endif
 241
 242                 /* Create new serial device */
 243                 port = kmalloc(sizeof(struct hp300_port), GFP_KERNEL);
 244                 if (!port)
 245                         return -ENOMEM;
 246
 247                 memset(&uart, 0, sizeof(uart));
 248
 249                 base = (FRODO_BASE + FRODO_APCI_OFFSET(i));
 250
 251                 /* Memory mapped I/O */
 252                 uart.port.iotype = UPIO_MEM;
 253                 uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ
 254                                 | UPF_BOOT_AUTOCONF;
 255                 /* XXX - no interrupt support yet */
 256                 uart.port.irq = 0;
 257                 uart.port.uartclk = HPAPCI_BAUD_BASE * 16;
 258                 uart.port.mapbase = base;
 259                 uart.port.membase = (char *)(base + DIO_VIRADDRBASE);
 260                 uart.port.regshift = 2;
 261
 262                 line = serial8250_register_8250_port(&uart);
 263
 264                 if (line < 0) {
 265                         dev_notice(uart.port.dev,
 266                                    "8250_hp300: register_serial() APCI %d irq %d failed\n",
 267                                    i, uart.port.irq);
 268                         kfree(port);
 269                         continue;
 270                 }
 271
 272                 port->line = line;
 273                 port->next = hp300_ports;
 274                 hp300_ports = port;
 275
 276                 num_ports++;
 277         }
 278 #endif
 279
 280         /* Any boards found? */
 281         if (!num_ports)
 282                 return -ENODEV;
 283
 284         return 0;
 285 }
 286
 287 #ifdef CONFIG_HPDCA
 288 static void hpdca_remove_one(struct dio_dev *d)
 289 {
 290         int line;
 291
 292         line = (int) dio_get_drvdata(d);
 293         if (d->resource.start) {
 294                 /* Disable board-interrupts */
 295                 out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, 0);
 296         }
 297         serial8250_unregister_port(line);
 298 }
 299 #endif
 300
 301 static void __exit hp300_8250_exit(void)
 302 {
 303 #ifdef CONFIG_HPAPCI
 304         struct hp300_port *port, *to_free;
 305
 306         for (port = hp300_ports; port; ) {
 307                 serial8250_unregister_port(port->line);
 308                 to_free = port;
 309                 port = port->next;
 310                 kfree(to_free);
 311         }
 312
 313         hp300_ports = NULL;
 314 #endif
 315 #ifdef CONFIG_HPDCA
 316         dio_unregister_driver(&hpdca_driver);
 317 #endif
 318 }
 319
 320 module_init(hp300_8250_init);
 321 module_exit(hp300_8250_exit);
 322 MODULE_DESCRIPTION("HP DCA/APCI serial driver");
 323 MODULE_AUTHOR("Kars de Jong <jongk@linux-m68k.org>");
 324 MODULE_LICENSE("GPL");