arch/powerpc/cpu/mpc512x/serial.c

   1 /*
   2  * (C) Copyright 2000 - 2010
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  *
   7  * Based ont the MPC5200 PSC driver.
   8  * Adapted for MPC512x by Jan Wrobel <wrr@semihalf.com>
   9  */
  10
  11 /*
  12  * Minimal serial functions needed to use one of the PSC ports
  13  * as serial console interface.
  14  */
  15
  16 #include <common.h>
  17 #include <linux/compiler.h>
  18 #include <asm/io.h>
  19 #include <asm/processor.h>
  20 #include <serial.h>
  21
  22 DECLARE_GLOBAL_DATA_PTR;
  23
  24 #if defined(CONFIG_PSC_CONSOLE)
  25
  26 static void fifo_init (volatile psc512x_t *psc)
  27 {
  28         volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
  29         u32 tfsize, rfsize;
  30
  31         /* reset Rx & Tx fifo slice */
  32         out_be32(&psc->rfcmd, PSC_FIFO_RESET_SLICE);
  33         out_be32(&psc->tfcmd, PSC_FIFO_RESET_SLICE);
  34
  35         /* disable Tx & Rx FIFO interrupts */
  36         out_be32(&psc->rfintmask, 0);
  37         out_be32(&psc->tfintmask, 0);
  38
  39         switch (((u32)psc & 0xf00) >> 8) {
  40         case 0:
  41                 tfsize = FIFOC_PSC0_TX_SIZE | (FIFOC_PSC0_TX_ADDR << 16);
  42                 rfsize = FIFOC_PSC0_RX_SIZE | (FIFOC_PSC0_RX_ADDR << 16);
  43                 break;
  44         case 1:
  45                 tfsize = FIFOC_PSC1_TX_SIZE | (FIFOC_PSC1_TX_ADDR << 16);
  46                 rfsize = FIFOC_PSC1_RX_SIZE | (FIFOC_PSC1_RX_ADDR << 16);
  47                 break;
  48         case 2:
  49                 tfsize = FIFOC_PSC2_TX_SIZE | (FIFOC_PSC2_TX_ADDR << 16);
  50                 rfsize = FIFOC_PSC2_RX_SIZE | (FIFOC_PSC2_RX_ADDR << 16);
  51                 break;
  52         case 3:
  53                 tfsize = FIFOC_PSC3_TX_SIZE | (FIFOC_PSC3_TX_ADDR << 16);
  54                 rfsize = FIFOC_PSC3_RX_SIZE | (FIFOC_PSC3_RX_ADDR << 16);
  55                 break;
  56         case 4:
  57                 tfsize = FIFOC_PSC4_TX_SIZE | (FIFOC_PSC4_TX_ADDR << 16);
  58                 rfsize = FIFOC_PSC4_RX_SIZE | (FIFOC_PSC4_RX_ADDR << 16);
  59                 break;
  60         case 5:
  61                 tfsize = FIFOC_PSC5_TX_SIZE | (FIFOC_PSC5_TX_ADDR << 16);
  62                 rfsize = FIFOC_PSC5_RX_SIZE | (FIFOC_PSC5_RX_ADDR << 16);
  63                 break;
  64         case 6:
  65                 tfsize = FIFOC_PSC6_TX_SIZE | (FIFOC_PSC6_TX_ADDR << 16);
  66                 rfsize = FIFOC_PSC6_RX_SIZE | (FIFOC_PSC6_RX_ADDR << 16);
  67                 break;
  68         case 7:
  69                 tfsize = FIFOC_PSC7_TX_SIZE | (FIFOC_PSC7_TX_ADDR << 16);
  70                 rfsize = FIFOC_PSC7_RX_SIZE | (FIFOC_PSC7_RX_ADDR << 16);
  71                 break;
  72         case 8:
  73                 tfsize = FIFOC_PSC8_TX_SIZE | (FIFOC_PSC8_TX_ADDR << 16);
  74                 rfsize = FIFOC_PSC8_RX_SIZE | (FIFOC_PSC8_RX_ADDR << 16);
  75                 break;
  76         case 9:
  77                 tfsize = FIFOC_PSC9_TX_SIZE | (FIFOC_PSC9_TX_ADDR << 16);
  78                 rfsize = FIFOC_PSC9_RX_SIZE | (FIFOC_PSC9_RX_ADDR << 16);
  79                 break;
  80         case 10:
  81                 tfsize = FIFOC_PSC10_TX_SIZE | (FIFOC_PSC10_TX_ADDR << 16);
  82                 rfsize = FIFOC_PSC10_RX_SIZE | (FIFOC_PSC10_RX_ADDR << 16);
  83                 break;
  84         case 11:
  85                 tfsize = FIFOC_PSC11_TX_SIZE | (FIFOC_PSC11_TX_ADDR << 16);
  86                 rfsize = FIFOC_PSC11_RX_SIZE | (FIFOC_PSC11_RX_ADDR << 16);
  87                 break;
  88         default:
  89                 return;
  90         }
  91
  92         out_be32(&psc->tfsize, tfsize);
  93         out_be32(&psc->rfsize, rfsize);
  94
  95         /* enable Tx & Rx FIFO slice */
  96         out_be32(&psc->rfcmd, PSC_FIFO_ENABLE_SLICE);
  97         out_be32(&psc->tfcmd, PSC_FIFO_ENABLE_SLICE);
  98
  99         out_be32(&im->fifoc.fifoc_cmd, FIFOC_DISABLE_CLOCK_GATE);
 100         __asm__ volatile ("sync");
 101 }
 102
 103 void serial_setbrg_dev(unsigned int idx)
 104 {
 105         volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
 106         volatile psc512x_t *psc = (psc512x_t *) &im->psc[idx];
 107         unsigned long baseclk, div;
 108         unsigned long baudrate;
 109         char buf[16];
 110         char *br_env;
 111
 112         baudrate = gd->baudrate;
 113         if (idx != CONFIG_PSC_CONSOLE) {
 114                 /* Allows setting baudrate for other serial devices
 115                  * on PSCx using environment. If not specified, use
 116                  * the same baudrate as for console.
 117                  */
 118                 sprintf(buf, "psc%d_baudrate", idx);
 119                 br_env = getenv(buf);
 120                 if (br_env)
 121                         baudrate = simple_strtoul(br_env, NULL, 10);
 122
 123                 debug("%s: idx %d, baudrate %ld\n", __func__, idx, baudrate);
 124         }
 125
 126         /* calculate divisor for setting PSC CTUR and CTLR registers */
 127         baseclk = (gd->arch.ips_clk + 8) / 16;
 128         div = (baseclk + (baudrate / 2)) / baudrate;
 129
 130         out_8(&psc->ctur, (div >> 8) & 0xff);
 131         out_8(&psc->ctlr,  div & 0xff); /* set baudrate */
 132 }
 133
 134 int serial_init_dev(unsigned int idx)
 135 {
 136         volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
 137         volatile psc512x_t *psc = (psc512x_t *) &im->psc[idx];
 138         u32 reg;
 139
 140         reg = in_be32(&im->clk.sccr[0]);
 141         out_be32(&im->clk.sccr[0], reg | CLOCK_SCCR1_PSC_EN(idx));
 142
 143         fifo_init (psc);
 144
 145         /* set MR register to point to MR1 */
 146         out_8(&psc->command, PSC_SEL_MODE_REG_1);
 147
 148         /* disable Tx/Rx */
 149         out_8(&psc->command, PSC_TX_DISABLE | PSC_RX_DISABLE);
 150
 151         /* choose the prescaler by 16 for the Tx/Rx clock generation */
 152         out_be16(&psc->psc_clock_select, 0xdd00);
 153
 154         /* switch to UART mode */
 155         out_be32(&psc->sicr, 0);
 156
 157         /* mode register points to mr1 */
 158         /* configure parity, bit length and so on in mode register 1*/
 159         out_8(&psc->mode, PSC_MODE_8_BITS | PSC_MODE_PARNONE);
 160         /* now, mode register points to mr2 */
 161         out_8(&psc->mode, PSC_MODE_1_STOPBIT);
 162
 163         /* set baudrate */
 164         serial_setbrg_dev(idx);
 165
 166         /* disable all interrupts */
 167         out_be16(&psc->psc_imr, 0);
 168
 169         /* reset and enable Rx/Tx */
 170         out_8(&psc->command, PSC_RST_RX);
 171         out_8(&psc->command, PSC_RST_TX);
 172         out_8(&psc->command, PSC_RX_ENABLE | PSC_TX_ENABLE);
 173
 174         return 0;
 175 }
 176
 177 int serial_uninit_dev(unsigned int idx)
 178 {
 179         volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
 180         volatile psc512x_t *psc = (psc512x_t *) &im->psc[idx];
 181         u32 reg;
 182
 183         out_8(&psc->command, PSC_RX_DISABLE | PSC_TX_DISABLE);
 184         reg = in_be32(&im->clk.sccr[0]);
 185         reg &= ~CLOCK_SCCR1_PSC_EN(idx);
 186         out_be32(&im->clk.sccr[0], reg);
 187
 188         return 0;
 189 }
 190
 191 void serial_putc_dev(unsigned int idx, const char c)
 192 {
 193         volatile immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
 194         volatile psc512x_t *psc = (psc512x_t *) &im->psc[idx];
 195
 196         if (c == '\n')
 197                 serial_putc_dev(idx, '\r');
 198
 199         /* Wait for last character to go. */
 200         while (!(in_be16(&psc->psc_status) & PSC_SR_TXEMP))
 201                 ;
 202
 203         out_8(&psc->tfdata_8, c);
 204 }
 205
 206 void serial_putc_raw_dev(unsigned int idx, const char c)
 207 {
 208         volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
 209         volatile psc512x_t *psc = (psc512x_t *) &im->psc[idx];
 210
 211         /* Wait for last character to go. */
 212         while (!(in_be16(&psc->psc_status) & PSC_SR_TXEMP))
 213                 ;
 214
 215         out_8(&psc->tfdata_8, c);
 216 }
 217
 218 void serial_puts_dev(unsigned int idx, const char *s)
 219 {
 220         while (*s)
 221                 serial_putc_dev(idx, *s++);
 222 }
 223
 224 int serial_getc_dev(unsigned int idx)
 225 {
 226         volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
 227         volatile psc512x_t *psc = (psc512x_t *) &im->psc[idx];
 228
 229         /* Wait for a character to arrive. */
 230         while (in_be32(&psc->rfstat) & PSC_FIFO_EMPTY)
 231                 ;
 232
 233         return in_8(&psc->rfdata_8);
 234 }
 235
 236 int serial_tstc_dev(unsigned int idx)
 237 {
 238         volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
 239         volatile psc512x_t *psc = (psc512x_t *) &im->psc[idx];
 240
 241         return !(in_be32(&psc->rfstat) & PSC_FIFO_EMPTY);
 242 }
 243
 244 void serial_setrts_dev(unsigned int idx, int s)
 245 {
 246         volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
 247         volatile psc512x_t *psc = (psc512x_t *) &im->psc[idx];
 248
 249         if (s) {
 250                 /* Assert RTS (become LOW) */
 251                 out_8(&psc->op1, 0x1);
 252         }
 253         else {
 254                 /* Negate RTS (become HIGH) */
 255                 out_8(&psc->op0, 0x1);
 256         }
 257 }
 258
 259 int serial_getcts_dev(unsigned int idx)
 260 {
 261         volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
 262         volatile psc512x_t *psc = (psc512x_t *) &im->psc[idx];
 263
 264         return (in_8(&psc->ip) & 0x1) ? 0 : 1;
 265 }
 266 #endif /* CONFIG_PSC_CONSOLE */
 267
 268 #define DECLARE_PSC_SERIAL_FUNCTIONS(port) \
 269         int serial##port##_init(void) \
 270         { \
 271                 return serial_init_dev(port); \
 272         } \
 273         int serial##port##_uninit(void) \
 274         { \
 275                 return serial_uninit_dev(port); \
 276         } \
 277         void serial##port##_setbrg(void) \
 278         { \
 279                 serial_setbrg_dev(port); \
 280         } \
 281         int serial##port##_getc(void) \
 282         { \
 283                 return serial_getc_dev(port); \
 284         } \
 285         int serial##port##_tstc(void) \
 286         { \
 287                 return serial_tstc_dev(port); \
 288         } \
 289         void serial##port##_putc(const char c) \
 290         { \
 291                 serial_putc_dev(port, c); \
 292         } \
 293         void serial##port##_puts(const char *s) \
 294         { \
 295                 serial_puts_dev(port, s); \
 296         }
 297
 298 #define INIT_PSC_SERIAL_STRUCTURE(port, __name) {       \
 299         .name   = __name,                               \
 300         .start  = serial##port##_init,                  \
 301         .stop   = serial##port##_uninit,                \
 302         .setbrg = serial##port##_setbrg,                \
 303         .getc   = serial##port##_getc,                  \
 304         .tstc   = serial##port##_tstc,                  \
 305         .putc   = serial##port##_putc,                  \
 306         .puts   = serial##port##_puts,                  \
 307 }
 308
 309 #if defined(CONFIG_SYS_PSC1)
 310 DECLARE_PSC_SERIAL_FUNCTIONS(1);
 311 struct serial_device serial1_device =
 312 INIT_PSC_SERIAL_STRUCTURE(1, "psc1");
 313 #endif
 314
 315 #if defined(CONFIG_SYS_PSC3)
 316 DECLARE_PSC_SERIAL_FUNCTIONS(3);
 317 struct serial_device serial3_device =
 318 INIT_PSC_SERIAL_STRUCTURE(3, "psc3");
 319 #endif
 320
 321 #if defined(CONFIG_SYS_PSC4)
 322 DECLARE_PSC_SERIAL_FUNCTIONS(4);
 323 struct serial_device serial4_device =
 324 INIT_PSC_SERIAL_STRUCTURE(4, "psc4");
 325 #endif
 326
 327 #if defined(CONFIG_SYS_PSC6)
 328 DECLARE_PSC_SERIAL_FUNCTIONS(6);
 329 struct serial_device serial6_device =
 330 INIT_PSC_SERIAL_STRUCTURE(6, "psc6");
 331 #endif
 332
 333 __weak struct serial_device *default_serial_console(void)
 334 {
 335 #if (CONFIG_PSC_CONSOLE == 3)
 336         return &serial3_device;
 337 #elif (CONFIG_PSC_CONSOLE == 6)
 338         return &serial6_device;
 339 #else
 340 #error "invalid CONFIG_PSC_CONSOLE"
 341 #endif
 342 }
 343
 344 void mpc512x_serial_initialize(void)
 345 {
 346 #if defined(CONFIG_SYS_PSC1)
 347         serial_register(&serial1_device);
 348 #endif
 349 #if defined(CONFIG_SYS_PSC3)
 350         serial_register(&serial3_device);
 351 #endif
 352 #if defined(CONFIG_SYS_PSC4)
 353         serial_register(&serial4_device);
 354 #endif
 355 #if defined(CONFIG_SYS_PSC6)
 356         serial_register(&serial6_device);
 357 #endif
 358 }
 359
 360 #include <stdio_dev.h>
 361 /*
 362  * Routines for communication with serial devices over PSC
 363  */
 364 /* Bitfield for initialized PSCs */
 365 static unsigned int initialized;
 366
 367 struct stdio_dev *open_port(int num, int baudrate)
 368 {
 369         struct stdio_dev *port;
 370         char env_var[16];
 371         char env_val[10];
 372         char name[7];
 373
 374         if (num < 0 || num > 11)
 375                 return NULL;
 376
 377         sprintf(name, "psc%d", num);
 378         port = stdio_get_by_name(name);
 379         if (!port)
 380                 return NULL;
 381
 382         if (!test_bit(num, &initialized)) {
 383                 sprintf(env_var, "psc%d_baudrate", num);
 384                 sprintf(env_val, "%d", baudrate);
 385                 setenv(env_var, env_val);
 386
 387                 if (port->start(port))
 388                         return NULL;
 389
 390                 set_bit(num, &initialized);
 391         }
 392
 393         return port;
 394 }
 395
 396 int close_port(int num)
 397 {
 398         struct stdio_dev *port;
 399         int ret;
 400         char name[7];
 401
 402         if (num < 0 || num > 11)
 403                 return -1;
 404
 405         sprintf(name, "psc%d", num);
 406         port = stdio_get_by_name(name);
 407         if (!port)
 408                 return -1;
 409
 410         ret = port->stop(port);
 411         clear_bit(num, &initialized);
 412
 413         return ret;
 414 }
 415
 416 int write_port(struct stdio_dev *port, char *buf)
 417 {
 418         if (!port || !buf)
 419                 return -1;
 420
 421         port->puts(port, buf);
 422
 423         return 0;
 424 }
 425
 426 int read_port(struct stdio_dev *port, char *buf, int size)
 427 {
 428         int cnt = 0;
 429
 430         if (!port || !buf)
 431                 return -1;
 432
 433         if (!size)
 434                 return 0;
 435
 436         while (port->tstc(port)) {
 437                 buf[cnt++] = port->getc(port);
 438                 if (cnt > size)
 439                         break;
 440         }
 441
 442         return cnt;
 443 }