src/jtag/drivers/imx_gpio.c

   1 /***************************************************************************
   2  *   Copyright (C) 2017 by Grzegorz Kostka, kostka.grzegorz@gmail.com      *
   3  *                                                                         *
   4  *   Based on bcm2835gpio.c                                                 *
   5  *                                                                         *
   6  *   This program is free software; you can redistribute it and/or modify  *
   7  *   it under the terms of the GNU General Public License as published by  *
   8  *   the Free Software Foundation; either version 2 of the License, or     *
   9  *   (at your option) any later version.                                   *
  10  *                                                                         *
  11  *   This program is distributed in the hope that it will be useful,       *
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  14  *   GNU General Public License for more details.                          *
  15  *                                                                         *
  16  *   You should have received a copy of the GNU General Public License     *
  17  *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
  18  ***************************************************************************/
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include "config.h"
  22 #endif
  23
  24 #include <jtag/interface.h>
  25 #include <transport/transport.h>
  26 #include "bitbang.h"
  27
  28 #include <sys/mman.h>
  29
  30 #define IMX_GPIO_BASE 0x0209c000
  31 #define IMX_GPIO_SIZE 0x00004000
  32 #define IMX_GPIO_REGS_COUNT 8
  33
  34 static uint32_t imx_gpio_peri_base = IMX_GPIO_BASE;
  35
  36 struct imx_gpio_regs {
  37         uint32_t dr;
  38         uint32_t gdir;
  39         uint32_t psr;
  40         uint32_t icr1;
  41         uint32_t icr2;
  42         uint32_t imr;
  43         uint32_t isr;
  44         uint32_t edge_sel;
  45 } __attribute__((aligned(IMX_GPIO_SIZE)));
  46
  47 static int dev_mem_fd;
  48 static volatile struct imx_gpio_regs *pio_base;
  49
  50 /* GPIO setup functions */
  51 static inline bool gpio_mode_get(int g)
  52 {
  53         return pio_base[g / 32].gdir >> (g & 0x1F) & 1;
  54 }
  55
  56 static inline void gpio_mode_input_set(int g)
  57 {
  58         pio_base[g / 32].gdir &=  ~(1u << (g & 0x1F));
  59 }
  60
  61 static inline void gpio_mode_output_set(int g)
  62 {
  63         pio_base[g / 32].gdir |=  (1u << (g & 0x1F));
  64 }
  65
  66 static inline void gpio_mode_set(int g, int m)
  67 {
  68         (m) ? gpio_mode_output_set(g) : gpio_mode_input_set(g);
  69 }
  70
  71 static inline void gpio_set(int g)
  72 {
  73         pio_base[g / 32].dr |=  (1u << (g & 0x1F));
  74 }
  75
  76 static inline void gpio_clear(int g)
  77 {
  78         pio_base[g / 32].dr &=  ~(1u << (g & 0x1F));
  79 }
  80
  81 static inline bool gpio_level(int g)
  82 {
  83         return pio_base[g / 32].dr >> (g & 0x1F) & 1;
  84 }
  85
  86 static bb_value_t imx_gpio_read(void);
  87 static int imx_gpio_write(int tck, int tms, int tdi);
  88
  89 static int imx_gpio_swdio_read(void);
  90 static void imx_gpio_swdio_drive(bool is_output);
  91 static int imx_gpio_swd_write(int swclk, int swdio);
  92
  93 static int imx_gpio_init(void);
  94 static int imx_gpio_quit(void);
  95
  96 static struct bitbang_interface imx_gpio_bitbang = {
  97         .read = imx_gpio_read,
  98         .write = imx_gpio_write,
  99         .swdio_read = imx_gpio_swdio_read,
 100         .swdio_drive = imx_gpio_swdio_drive,
 101         .swd_write = imx_gpio_swd_write,
 102         .blink = NULL
 103 };
 104
 105 /* GPIO numbers for each signal. Negative values are invalid */
 106 static int tck_gpio = -1;
 107 static int tck_gpio_mode;
 108 static int tms_gpio = -1;
 109 static int tms_gpio_mode;
 110 static int tdi_gpio = -1;
 111 static int tdi_gpio_mode;
 112 static int tdo_gpio = -1;
 113 static int tdo_gpio_mode;
 114 static int trst_gpio = -1;
 115 static int trst_gpio_mode;
 116 static int srst_gpio = -1;
 117 static int srst_gpio_mode;
 118 static int swclk_gpio = -1;
 119 static int swclk_gpio_mode;
 120 static int swdio_gpio = -1;
 121 static int swdio_gpio_mode;
 122
 123 /* Transition delay coefficients. Tuned for IMX6UL 528MHz. Adjusted
 124  * experimentally for:10kHz, 100Khz, 500KHz. Speeds above 800Khz are impossible
 125  * to reach via memory mapped method (at least for IMX6UL@528MHz).
 126  * Measured mmap raw GPIO toggling speed on IMX6UL@528MHz: 1.3MHz.
 127  */
 128 static int speed_coeff = 50000;
 129 static int speed_offset = 100;
 130 static unsigned int jtag_delay;
 131
 132 static bb_value_t imx_gpio_read(void)
 133 {
 134         return gpio_level(tdo_gpio) ? BB_HIGH : BB_LOW;
 135 }
 136
 137 static int imx_gpio_write(int tck, int tms, int tdi)
 138 {
 139         tms ? gpio_set(tms_gpio) : gpio_clear(tms_gpio);
 140         tdi ? gpio_set(tdi_gpio) : gpio_clear(tdi_gpio);
 141         tck ? gpio_set(tck_gpio) : gpio_clear(tck_gpio);
 142
 143         for (unsigned int i = 0; i < jtag_delay; i++)
 144                 asm volatile ("");
 145
 146         return ERROR_OK;
 147 }
 148
 149 static int imx_gpio_swd_write(int swclk, int swdio)
 150 {
 151         swdio ? gpio_set(swdio_gpio) : gpio_clear(swdio_gpio);
 152         swclk ? gpio_set(swclk_gpio) : gpio_clear(swclk_gpio);
 153
 154         for (unsigned int i = 0; i < jtag_delay; i++)
 155                 asm volatile ("");
 156
 157         return ERROR_OK;
 158 }
 159
 160 /* (1) assert or (0) deassert reset lines */
 161 static int imx_gpio_reset(int trst, int srst)
 162 {
 163         if (trst_gpio != -1)
 164                 trst ? gpio_clear(trst_gpio) : gpio_set(trst_gpio);
 165
 166         if (srst_gpio != -1)
 167                 srst ? gpio_clear(srst_gpio) : gpio_set(srst_gpio);
 168
 169         return ERROR_OK;
 170 }
 171
 172 static void imx_gpio_swdio_drive(bool is_output)
 173 {
 174         if (is_output)
 175                 gpio_mode_output_set(swdio_gpio);
 176         else
 177                 gpio_mode_input_set(swdio_gpio);
 178 }
 179
 180 static int imx_gpio_swdio_read(void)
 181 {
 182         return gpio_level(swdio_gpio);
 183 }
 184
 185 static int imx_gpio_khz(int khz, int *jtag_speed)
 186 {
 187         if (!khz) {
 188                 LOG_DEBUG("RCLK not supported");
 189                 return ERROR_FAIL;
 190         }
 191         *jtag_speed = speed_coeff/khz - speed_offset;
 192         if (*jtag_speed < 0)
 193                 *jtag_speed = 0;
 194         return ERROR_OK;
 195 }
 196
 197 static int imx_gpio_speed_div(int speed, int *khz)
 198 {
 199         *khz = speed_coeff/(speed + speed_offset);
 200         return ERROR_OK;
 201 }
 202
 203 static int imx_gpio_speed(int speed)
 204 {
 205         jtag_delay = speed;
 206         return ERROR_OK;
 207 }
 208
 209 static int is_gpio_valid(int gpio)
 210 {
 211         return gpio >= 0 && gpio < 32 * IMX_GPIO_REGS_COUNT;
 212 }
 213
 214 COMMAND_HANDLER(imx_gpio_handle_jtag_gpionums)
 215 {
 216         if (CMD_ARGC == 4) {
 217                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tck_gpio);
 218                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], tms_gpio);
 219                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[2], tdi_gpio);
 220                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[3], tdo_gpio);
 221         } else if (CMD_ARGC != 0) {
 222                 return ERROR_COMMAND_SYNTAX_ERROR;
 223         }
 224
 225         command_print(CMD,
 226                         "imx_gpio GPIO config: tck = %d, tms = %d, tdi = %d, tdo = %d",
 227                         tck_gpio, tms_gpio, tdi_gpio, tdo_gpio);
 228
 229         return ERROR_OK;
 230 }
 231
 232 COMMAND_HANDLER(imx_gpio_handle_jtag_gpionum_tck)
 233 {
 234         if (CMD_ARGC == 1)
 235                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tck_gpio);
 236
 237         command_print(CMD, "imx_gpio GPIO config: tck = %d", tck_gpio);
 238         return ERROR_OK;
 239 }
 240
 241 COMMAND_HANDLER(imx_gpio_handle_jtag_gpionum_tms)
 242 {
 243         if (CMD_ARGC == 1)
 244                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tms_gpio);
 245
 246         command_print(CMD, "imx_gpio GPIO config: tms = %d", tms_gpio);
 247         return ERROR_OK;
 248 }
 249
 250 COMMAND_HANDLER(imx_gpio_handle_jtag_gpionum_tdo)
 251 {
 252         if (CMD_ARGC == 1)
 253                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tdo_gpio);
 254
 255         command_print(CMD, "imx_gpio GPIO config: tdo = %d", tdo_gpio);
 256         return ERROR_OK;
 257 }
 258
 259 COMMAND_HANDLER(imx_gpio_handle_jtag_gpionum_tdi)
 260 {
 261         if (CMD_ARGC == 1)
 262                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tdi_gpio);
 263
 264         command_print(CMD, "imx_gpio GPIO config: tdi = %d", tdi_gpio);
 265         return ERROR_OK;
 266 }
 267
 268 COMMAND_HANDLER(imx_gpio_handle_jtag_gpionum_srst)
 269 {
 270         if (CMD_ARGC == 1)
 271                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], srst_gpio);
 272
 273         command_print(CMD, "imx_gpio GPIO config: srst = %d", srst_gpio);
 274         return ERROR_OK;
 275 }
 276
 277 COMMAND_HANDLER(imx_gpio_handle_jtag_gpionum_trst)
 278 {
 279         if (CMD_ARGC == 1)
 280                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], trst_gpio);
 281
 282         command_print(CMD, "imx_gpio GPIO config: trst = %d", trst_gpio);
 283         return ERROR_OK;
 284 }
 285
 286 COMMAND_HANDLER(imx_gpio_handle_swd_gpionums)
 287 {
 288         if (CMD_ARGC == 2) {
 289                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swclk_gpio);
 290                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], swdio_gpio);
 291         } else if (CMD_ARGC != 0) {
 292                 return ERROR_COMMAND_SYNTAX_ERROR;
 293         }
 294
 295         command_print(CMD,
 296                         "imx_gpio GPIO nums: swclk = %d, swdio = %d",
 297                         swclk_gpio, swdio_gpio);
 298
 299         return ERROR_OK;
 300 }
 301
 302 COMMAND_HANDLER(imx_gpio_handle_swd_gpionum_swclk)
 303 {
 304         if (CMD_ARGC == 1)
 305                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swclk_gpio);
 306
 307         command_print(CMD, "imx_gpio num: swclk = %d", swclk_gpio);
 308         return ERROR_OK;
 309 }
 310
 311 COMMAND_HANDLER(imx_gpio_handle_swd_gpionum_swdio)
 312 {
 313         if (CMD_ARGC == 1)
 314                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swdio_gpio);
 315
 316         command_print(CMD, "imx_gpio num: swdio = %d", swdio_gpio);
 317         return ERROR_OK;
 318 }
 319
 320 COMMAND_HANDLER(imx_gpio_handle_speed_coeffs)
 321 {
 322         if (CMD_ARGC == 2) {
 323                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], speed_coeff);
 324                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], speed_offset);
 325         }
 326
 327         command_print(CMD, "imx_gpio: speed_coeffs = %d, speed_offset = %d",
 328                                   speed_coeff, speed_offset);
 329         return ERROR_OK;
 330 }
 331
 332 COMMAND_HANDLER(imx_gpio_handle_peripheral_base)
 333 {
 334         if (CMD_ARGC == 1)
 335                 COMMAND_PARSE_NUMBER(u32, CMD_ARGV[0], imx_gpio_peri_base);
 336
 337         command_print(CMD, "imx_gpio: peripheral_base = 0x%08x",
 338                                   imx_gpio_peri_base);
 339         return ERROR_OK;
 340 }
 341
 342 static const struct command_registration imx_gpio_command_handlers[] = {
 343         {
 344                 .name = "imx_gpio_jtag_nums",
 345                 .handler = &imx_gpio_handle_jtag_gpionums,
 346                 .mode = COMMAND_CONFIG,
 347                 .help = "gpio numbers for tck, tms, tdi, tdo. (in that order)",
 348                 .usage = "[tck tms tdi tdo]",
 349         },
 350         {
 351                 .name = "imx_gpio_tck_num",
 352                 .handler = &imx_gpio_handle_jtag_gpionum_tck,
 353                 .mode = COMMAND_CONFIG,
 354                 .help = "gpio number for tck.",
 355                 .usage = "[tck]",
 356         },
 357         {
 358                 .name = "imx_gpio_tms_num",
 359                 .handler = &imx_gpio_handle_jtag_gpionum_tms,
 360                 .mode = COMMAND_CONFIG,
 361                 .help = "gpio number for tms.",
 362                 .usage = "[tms]",
 363         },
 364         {
 365                 .name = "imx_gpio_tdo_num",
 366                 .handler = &imx_gpio_handle_jtag_gpionum_tdo,
 367                 .mode = COMMAND_CONFIG,
 368                 .help = "gpio number for tdo.",
 369                 .usage = "[tdo]",
 370         },
 371         {
 372                 .name = "imx_gpio_tdi_num",
 373                 .handler = &imx_gpio_handle_jtag_gpionum_tdi,
 374                 .mode = COMMAND_CONFIG,
 375                 .help = "gpio number for tdi.",
 376                 .usage = "[tdi]",
 377         },
 378         {
 379                 .name = "imx_gpio_swd_nums",
 380                 .handler = &imx_gpio_handle_swd_gpionums,
 381                 .mode = COMMAND_CONFIG,
 382                 .help = "gpio numbers for swclk, swdio. (in that order)",
 383                 .usage = "[swclk swdio]",
 384         },
 385         {
 386                 .name = "imx_gpio_swclk_num",
 387                 .handler = &imx_gpio_handle_swd_gpionum_swclk,
 388                 .mode = COMMAND_CONFIG,
 389                 .help = "gpio number for swclk.",
 390                 .usage = "[swclk]",
 391         },
 392         {
 393                 .name = "imx_gpio_swdio_num",
 394                 .handler = &imx_gpio_handle_swd_gpionum_swdio,
 395                 .mode = COMMAND_CONFIG,
 396                 .help = "gpio number for swdio.",
 397                 .usage = "[swdio]",
 398         },
 399         {
 400                 .name = "imx_gpio_srst_num",
 401                 .handler = &imx_gpio_handle_jtag_gpionum_srst,
 402                 .mode = COMMAND_CONFIG,
 403                 .help = "gpio number for srst.",
 404                 .usage = "[srst]",
 405         },
 406         {
 407                 .name = "imx_gpio_trst_num",
 408                 .handler = &imx_gpio_handle_jtag_gpionum_trst,
 409                 .mode = COMMAND_CONFIG,
 410                 .help = "gpio number for trst.",
 411                 .usage = "[trst]",
 412         },
 413         {
 414                 .name = "imx_gpio_speed_coeffs",
 415                 .handler = &imx_gpio_handle_speed_coeffs,
 416                 .mode = COMMAND_CONFIG,
 417                 .help = "SPEED_COEFF and SPEED_OFFSET for delay calculations.",
 418                 .usage = "[SPEED_COEFF SPEED_OFFSET]",
 419         },
 420         {
 421                 .name = "imx_gpio_peripheral_base",
 422                 .handler = &imx_gpio_handle_peripheral_base,
 423                 .mode = COMMAND_CONFIG,
 424                 .help = "peripheral base to access GPIOs (0x0209c000 for most IMX).",
 425                 .usage = "[base]",
 426         },
 427
 428         COMMAND_REGISTRATION_DONE
 429 };
 430
 431 static const char * const imx_gpio_transports[] = { "jtag", "swd", NULL };
 432
 433 static struct jtag_interface imx_gpio_interface = {
 434         .supported = DEBUG_CAP_TMS_SEQ,
 435         .execute_queue = bitbang_execute_queue,
 436 };
 437
 438 struct adapter_driver imx_gpio_adapter_driver = {
 439         .name = "imx_gpio",
 440         .transports = imx_gpio_transports,
 441         .commands = imx_gpio_command_handlers,
 442
 443         .init = imx_gpio_init,
 444         .quit = imx_gpio_quit,
 445         .reset = imx_gpio_reset,
 446         .speed = imx_gpio_speed,
 447         .khz = imx_gpio_khz,
 448         .speed_div = imx_gpio_speed_div,
 449
 450         .jtag_ops = &imx_gpio_interface,
 451         .swd_ops = &bitbang_swd,
 452 };
 453
 454 static bool imx_gpio_jtag_mode_possible(void)
 455 {
 456         if (!is_gpio_valid(tck_gpio))
 457                 return 0;
 458         if (!is_gpio_valid(tms_gpio))
 459                 return 0;
 460         if (!is_gpio_valid(tdi_gpio))
 461                 return 0;
 462         if (!is_gpio_valid(tdo_gpio))
 463                 return 0;
 464         return 1;
 465 }
 466
 467 static bool imx_gpio_swd_mode_possible(void)
 468 {
 469         if (!is_gpio_valid(swclk_gpio))
 470                 return 0;
 471         if (!is_gpio_valid(swdio_gpio))
 472                 return 0;
 473         return 1;
 474 }
 475
 476 static int imx_gpio_init(void)
 477 {
 478         bitbang_interface = &imx_gpio_bitbang;
 479
 480         LOG_INFO("imx_gpio GPIO JTAG/SWD bitbang driver");
 481
 482         if (transport_is_jtag() && !imx_gpio_jtag_mode_possible()) {
 483                 LOG_ERROR("Require tck, tms, tdi and tdo gpios for JTAG mode");
 484                 return ERROR_JTAG_INIT_FAILED;
 485         }
 486
 487         if (transport_is_swd() && !imx_gpio_swd_mode_possible()) {
 488                 LOG_ERROR("Require swclk and swdio gpio for SWD mode");
 489                 return ERROR_JTAG_INIT_FAILED;
 490         }
 491
 492         dev_mem_fd = open("/dev/mem", O_RDWR | O_SYNC);
 493         if (dev_mem_fd < 0) {
 494                 LOG_ERROR("open: %s", strerror(errno));
 495                 return ERROR_JTAG_INIT_FAILED;
 496         }
 497
 498         LOG_INFO("imx_gpio mmap: pagesize: %u, regionsize: %u",
 499                         (unsigned int) sysconf(_SC_PAGE_SIZE), IMX_GPIO_REGS_COUNT * IMX_GPIO_SIZE);
 500         pio_base = mmap(NULL, IMX_GPIO_REGS_COUNT * IMX_GPIO_SIZE,
 501                                 PROT_READ | PROT_WRITE,
 502                                 MAP_SHARED, dev_mem_fd, imx_gpio_peri_base);
 503
 504         if (pio_base == MAP_FAILED) {
 505                 LOG_ERROR("mmap: %s", strerror(errno));
 506                 close(dev_mem_fd);
 507                 return ERROR_JTAG_INIT_FAILED;
 508         }
 509
 510         /*
 511          * Configure TDO as an input, and TDI, TCK, TMS, TRST, SRST
 512          * as outputs.  Drive TDI and TCK low, and TMS/TRST/SRST high.
 513          */
 514         if (transport_is_jtag()) {
 515                 tdo_gpio_mode = gpio_mode_get(tdo_gpio);
 516                 tdi_gpio_mode = gpio_mode_get(tdi_gpio);
 517                 tck_gpio_mode = gpio_mode_get(tck_gpio);
 518                 tms_gpio_mode = gpio_mode_get(tms_gpio);
 519
 520                 gpio_clear(tdi_gpio);
 521                 gpio_clear(tck_gpio);
 522                 gpio_set(tms_gpio);
 523
 524                 gpio_mode_input_set(tdo_gpio);
 525                 gpio_mode_output_set(tdi_gpio);
 526                 gpio_mode_output_set(tck_gpio);
 527                 gpio_mode_output_set(tms_gpio);
 528
 529                 if (trst_gpio != -1) {
 530                         trst_gpio_mode = gpio_mode_get(trst_gpio);
 531                         gpio_set(trst_gpio);
 532                         gpio_mode_output_set(trst_gpio);
 533                 }
 534         }
 535
 536         if (transport_is_swd()) {
 537                 swclk_gpio_mode = gpio_mode_get(swclk_gpio);
 538                 swdio_gpio_mode = gpio_mode_get(swdio_gpio);
 539
 540                 gpio_clear(swdio_gpio);
 541                 gpio_clear(swclk_gpio);
 542                 gpio_mode_output_set(swclk_gpio);
 543                 gpio_mode_output_set(swdio_gpio);
 544         }
 545
 546         if (srst_gpio != -1) {
 547                 srst_gpio_mode = gpio_mode_get(srst_gpio);
 548                 gpio_set(srst_gpio);
 549                 gpio_mode_output_set(srst_gpio);
 550         }
 551
 552         LOG_DEBUG("saved pinmux settings: tck %d tms %d tdi %d "
 553                   "tdo %d trst %d srst %d", tck_gpio_mode, tms_gpio_mode,
 554                   tdi_gpio_mode, tdo_gpio_mode, trst_gpio_mode, srst_gpio_mode);
 555
 556         return ERROR_OK;
 557 }
 558
 559 static int imx_gpio_quit(void)
 560 {
 561         if (transport_is_jtag()) {
 562                 gpio_mode_set(tdo_gpio, tdo_gpio_mode);
 563                 gpio_mode_set(tdi_gpio, tdi_gpio_mode);
 564                 gpio_mode_set(tck_gpio, tck_gpio_mode);
 565                 gpio_mode_set(tms_gpio, tms_gpio_mode);
 566
 567                 if (trst_gpio != -1)
 568                         gpio_mode_set(trst_gpio, trst_gpio_mode);
 569         }
 570
 571         if (transport_is_swd()) {
 572                 gpio_mode_set(swclk_gpio, swclk_gpio_mode);
 573                 gpio_mode_set(swdio_gpio, swdio_gpio_mode);
 574         }
 575
 576         if (srst_gpio != -1)
 577                 gpio_mode_set(srst_gpio, srst_gpio_mode);
 578
 579         return ERROR_OK;
 580 }