1 /***************************************************************************
2 * Copyright (C) 2013 by Paul Fertser, fercerpav@gmail.com *
4 * Copyright (C) 2012 by Creative Product Design, marc @ cpdesign.com.au *
5 * Based on at91rm9200.c (c) Anders Larsen *
6 * and RPi GPIO examples by Gert van Loo & Dom *
8 * This program is free software; you can redistribute it and/or modify *
9 * it under the terms of the GNU General Public License as published by *
10 * the Free Software Foundation; either version 2 of the License, or *
11 * (at your option) any later version. *
13 * This program is distributed in the hope that it will be useful, *
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of *
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
16 * GNU General Public License for more details. *
18 * You should have received a copy of the GNU General Public License *
19 * along with this program; if not, write to the *
20 * Free Software Foundation, Inc., *
21 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. *
22 ***************************************************************************/
28 #include <jtag/interface.h>
33 uint32_t bcm2835_peri_base = 0x20000000;
34 #define BCM2835_GPIO_BASE (bcm2835_peri_base + 0x200000) /* GPIO controller */
36 #define BCM2835_PADS_GPIO_0_27 (bcm2835_peri_base + 0x100000)
37 #define BCM2835_PADS_GPIO_0_27_OFFSET (0x2c / 4)
39 /* GPIO setup macros */
40 #define MODE_GPIO(g) (*(pio_base+((g)/10))>>(((g)%10)*3) & 7)
41 #define INP_GPIO(g) do { *(pio_base+((g)/10)) &= ~(7<<(((g)%10)*3)); } while (0)
42 #define SET_MODE_GPIO(g, m) do { /* clear the mode bits first, then set as necessary */ \
44 *(pio_base+((g)/10)) |= ((m)<<(((g)%10)*3)); } while (0)
45 #define OUT_GPIO(g) SET_MODE_GPIO(g, 1)
47 #define GPIO_SET (*(pio_base+7)) /* sets bits which are 1, ignores bits which are 0 */
48 #define GPIO_CLR (*(pio_base+10)) /* clears bits which are 1, ignores bits which are 0 */
49 #define GPIO_LEV (*(pio_base+13)) /* current level of the pin */
51 static int dev_mem_fd;
52 static volatile uint32_t *pio_base;
54 static int bcm2835gpio_read(void);
55 static void bcm2835gpio_write(int tck, int tms, int tdi);
56 static void bcm2835gpio_reset(int trst, int srst);
58 static int bcm2835_swdio_read(void);
59 static void bcm2835_swdio_drive(bool is_output);
61 static int bcm2835gpio_init(void);
62 static int bcm2835gpio_quit(void);
64 static struct bitbang_interface bcm2835gpio_bitbang = {
65 .read = bcm2835gpio_read,
66 .write = bcm2835gpio_write,
67 .reset = bcm2835gpio_reset,
68 .swdio_read = bcm2835_swdio_read,
69 .swdio_drive = bcm2835_swdio_drive,
73 /* GPIO numbers for each signal. Negative values are invalid */
74 static int tck_gpio = -1;
75 static int tck_gpio_mode;
76 static int tms_gpio = -1;
77 static int tms_gpio_mode;
78 static int tdi_gpio = -1;
79 static int tdi_gpio_mode;
80 static int tdo_gpio = -1;
81 static int tdo_gpio_mode;
82 static int trst_gpio = -1;
83 static int trst_gpio_mode;
84 static int srst_gpio = -1;
85 static int srst_gpio_mode;
86 static int swclk_gpio = -1;
87 static int swclk_gpio_mode;
88 static int swdio_gpio = -1;
89 static int swdio_gpio_mode;
91 /* Transition delay coefficients */
92 static int speed_coeff = 113714;
93 static int speed_offset = 28;
94 static unsigned int jtag_delay;
96 static int bcm2835gpio_read(void)
98 return !!(GPIO_LEV & 1<<tdo_gpio);
101 static void bcm2835gpio_write(int tck, int tms, int tdi)
103 uint32_t set = tck<<tck_gpio | tms<<tms_gpio | tdi<<tdi_gpio;
104 uint32_t clear = !tck<<tck_gpio | !tms<<tms_gpio | !tdi<<tdi_gpio;
109 for (unsigned int i = 0; i < jtag_delay; i++)
113 static void bcm2835gpio_swd_write(int tck, int tms, int tdi)
115 uint32_t set = tck<<swclk_gpio | tdi<<swdio_gpio;
116 uint32_t clear = !tck<<swclk_gpio | !tdi<<swdio_gpio;
121 for (unsigned int i = 0; i < jtag_delay; i++)
125 /* (1) assert or (0) deassert reset lines */
126 static void bcm2835gpio_reset(int trst, int srst)
132 set |= !trst<<trst_gpio;
133 clear |= trst<<trst_gpio;
137 set |= !srst<<srst_gpio;
138 clear |= srst<<srst_gpio;
145 static void bcm2835_swdio_drive(bool is_output)
148 OUT_GPIO(swdio_gpio);
150 INP_GPIO(swdio_gpio);
153 static int bcm2835_swdio_read(void)
155 return !!(GPIO_LEV & 1 << swdio_gpio);
158 static int bcm2835gpio_khz(int khz, int *jtag_speed)
161 LOG_DEBUG("RCLK not supported");
164 *jtag_speed = speed_coeff/khz - speed_offset;
170 static int bcm2835gpio_speed_div(int speed, int *khz)
172 *khz = speed_coeff/(speed + speed_offset);
176 static int bcm2835gpio_speed(int speed)
182 static int is_gpio_valid(int gpio)
184 return gpio >= 0 && gpio <= 53;
187 COMMAND_HANDLER(bcm2835gpio_handle_jtag_gpionums)
190 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tck_gpio);
191 COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], tms_gpio);
192 COMMAND_PARSE_NUMBER(int, CMD_ARGV[2], tdi_gpio);
193 COMMAND_PARSE_NUMBER(int, CMD_ARGV[3], tdo_gpio);
194 } else if (CMD_ARGC != 0) {
195 return ERROR_COMMAND_SYNTAX_ERROR;
198 command_print(CMD_CTX,
199 "BCM2835 GPIO config: tck = %d, tms = %d, tdi = %d, tdi = %d",
200 tck_gpio, tms_gpio, tdi_gpio, tdo_gpio);
205 COMMAND_HANDLER(bcm2835gpio_handle_jtag_gpionum_tck)
208 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tck_gpio);
210 command_print(CMD_CTX, "BCM2835 GPIO config: tck = %d", tck_gpio);
214 COMMAND_HANDLER(bcm2835gpio_handle_jtag_gpionum_tms)
217 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tms_gpio);
219 command_print(CMD_CTX, "BCM2835 GPIO config: tms = %d", tms_gpio);
223 COMMAND_HANDLER(bcm2835gpio_handle_jtag_gpionum_tdo)
226 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tdo_gpio);
228 command_print(CMD_CTX, "BCM2835 GPIO config: tdo = %d", tdo_gpio);
232 COMMAND_HANDLER(bcm2835gpio_handle_jtag_gpionum_tdi)
235 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tdi_gpio);
237 command_print(CMD_CTX, "BCM2835 GPIO config: tdi = %d", tdi_gpio);
241 COMMAND_HANDLER(bcm2835gpio_handle_jtag_gpionum_srst)
244 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], srst_gpio);
246 command_print(CMD_CTX, "BCM2835 GPIO config: srst = %d", srst_gpio);
250 COMMAND_HANDLER(bcm2835gpio_handle_jtag_gpionum_trst)
253 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], trst_gpio);
255 command_print(CMD_CTX, "BCM2835 GPIO config: trst = %d", trst_gpio);
259 COMMAND_HANDLER(bcm2835gpio_handle_swd_gpionums)
262 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swclk_gpio);
263 COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], swdio_gpio);
264 } else if (CMD_ARGC != 0) {
265 return ERROR_COMMAND_SYNTAX_ERROR;
268 command_print(CMD_CTX,
269 "BCM2835 GPIO nums: swclk = %d, swdio = %d",
270 swclk_gpio, swdio_gpio);
275 COMMAND_HANDLER(bcm2835gpio_handle_swd_gpionum_swclk)
278 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swclk_gpio);
280 command_print(CMD_CTX, "BCM2835 num: swclk = %d", swclk_gpio);
284 COMMAND_HANDLER(bcm2835gpio_handle_swd_gpionum_swdio)
287 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swdio_gpio);
289 command_print(CMD_CTX, "BCM2835 num: swdio = %d", swdio_gpio);
293 COMMAND_HANDLER(bcm2835gpio_handle_speed_coeffs)
296 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], speed_coeff);
297 COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], speed_offset);
302 COMMAND_HANDLER(bcm2835gpio_handle_peripheral_base)
305 COMMAND_PARSE_NUMBER(u32, CMD_ARGV[0], bcm2835_peri_base);
309 static const struct command_registration bcm2835gpio_command_handlers[] = {
311 .name = "bcm2835gpio_jtag_nums",
312 .handler = &bcm2835gpio_handle_jtag_gpionums,
313 .mode = COMMAND_CONFIG,
314 .help = "gpio numbers for tck, tms, tdi, tdo. (in that order)",
315 .usage = "(tck tms tdi tdo)* ",
318 .name = "bcm2835gpio_tck_num",
319 .handler = &bcm2835gpio_handle_jtag_gpionum_tck,
320 .mode = COMMAND_CONFIG,
321 .help = "gpio number for tck.",
324 .name = "bcm2835gpio_tms_num",
325 .handler = &bcm2835gpio_handle_jtag_gpionum_tms,
326 .mode = COMMAND_CONFIG,
327 .help = "gpio number for tms.",
330 .name = "bcm2835gpio_tdo_num",
331 .handler = &bcm2835gpio_handle_jtag_gpionum_tdo,
332 .mode = COMMAND_CONFIG,
333 .help = "gpio number for tdo.",
336 .name = "bcm2835gpio_tdi_num",
337 .handler = &bcm2835gpio_handle_jtag_gpionum_tdi,
338 .mode = COMMAND_CONFIG,
339 .help = "gpio number for tdi.",
342 .name = "bcm2835gpio_swd_nums",
343 .handler = &bcm2835gpio_handle_swd_gpionums,
344 .mode = COMMAND_CONFIG,
345 .help = "gpio numbers for swclk, swdio. (in that order)",
346 .usage = "(swclk swdio)* ",
349 .name = "bcm2835gpio_swclk_num",
350 .handler = &bcm2835gpio_handle_swd_gpionum_swclk,
351 .mode = COMMAND_CONFIG,
352 .help = "gpio number for swclk.",
355 .name = "bcm2835gpio_swdio_num",
356 .handler = &bcm2835gpio_handle_swd_gpionum_swdio,
357 .mode = COMMAND_CONFIG,
358 .help = "gpio number for swdio.",
361 .name = "bcm2835gpio_srst_num",
362 .handler = &bcm2835gpio_handle_jtag_gpionum_srst,
363 .mode = COMMAND_CONFIG,
364 .help = "gpio number for srst.",
367 .name = "bcm2835gpio_trst_num",
368 .handler = &bcm2835gpio_handle_jtag_gpionum_trst,
369 .mode = COMMAND_CONFIG,
370 .help = "gpio number for trst.",
373 .name = "bcm2835gpio_speed_coeffs",
374 .handler = &bcm2835gpio_handle_speed_coeffs,
375 .mode = COMMAND_CONFIG,
376 .help = "SPEED_COEFF and SPEED_OFFSET for delay calculations.",
379 .name = "bcm2835gpio_peripheral_base",
380 .handler = &bcm2835gpio_handle_peripheral_base,
381 .mode = COMMAND_CONFIG,
382 .help = "peripheral base to access GPIOs (RPi1 0x20000000, RPi2 0x3F000000).",
385 COMMAND_REGISTRATION_DONE
388 static const char * const bcm2835_transports[] = { "jtag", "swd", NULL };
390 struct jtag_interface bcm2835gpio_interface = {
391 .name = "bcm2835gpio",
392 .supported = DEBUG_CAP_TMS_SEQ,
393 .execute_queue = bitbang_execute_queue,
394 .transports = bcm2835_transports,
396 .speed = bcm2835gpio_speed,
397 .khz = bcm2835gpio_khz,
398 .speed_div = bcm2835gpio_speed_div,
399 .commands = bcm2835gpio_command_handlers,
400 .init = bcm2835gpio_init,
401 .quit = bcm2835gpio_quit,
404 static bool bcm2835gpio_jtag_mode_possible(void)
406 if (!is_gpio_valid(tck_gpio))
408 if (!is_gpio_valid(tms_gpio))
410 if (!is_gpio_valid(tdi_gpio))
412 if (!is_gpio_valid(tdo_gpio))
417 static bool bcm2835gpio_swd_mode_possible(void)
419 if (!is_gpio_valid(swclk_gpio))
421 if (!is_gpio_valid(swdio_gpio))
426 static int bcm2835gpio_init(void)
428 bitbang_interface = &bcm2835gpio_bitbang;
430 LOG_INFO("BCM2835 GPIO JTAG/SWD bitbang driver");
432 if (bcm2835gpio_jtag_mode_possible()) {
433 if (bcm2835gpio_swd_mode_possible())
434 LOG_INFO("JTAG and SWD modes enabled");
436 LOG_INFO("JTAG only mode enabled (specify swclk and swdio gpio to add SWD mode)");
437 if (!is_gpio_valid(trst_gpio) && !is_gpio_valid(srst_gpio)) {
438 LOG_ERROR("Require at least one of trst or srst gpios to be specified");
439 return ERROR_JTAG_INIT_FAILED;
441 } else if (bcm2835gpio_swd_mode_possible()) {
442 LOG_INFO("SWD only mode enabled (specify tck, tms, tdi and tdo gpios to add JTAG mode)");
444 LOG_ERROR("Require tck, tms, tdi and tdo gpios for JTAG mode and/or swclk and swdio gpio for SWD mode");
445 return ERROR_JTAG_INIT_FAILED;
448 dev_mem_fd = open("/dev/mem", O_RDWR | O_SYNC);
449 if (dev_mem_fd < 0) {
451 return ERROR_JTAG_INIT_FAILED;
454 pio_base = mmap(NULL, sysconf(_SC_PAGE_SIZE), PROT_READ | PROT_WRITE,
455 MAP_SHARED, dev_mem_fd, BCM2835_GPIO_BASE);
457 if (pio_base == MAP_FAILED) {
460 return ERROR_JTAG_INIT_FAILED;
463 static volatile uint32_t *pads_base;
464 pads_base = mmap(NULL, sysconf(_SC_PAGE_SIZE), PROT_READ | PROT_WRITE,
465 MAP_SHARED, dev_mem_fd, BCM2835_PADS_GPIO_0_27);
467 if (pads_base == MAP_FAILED) {
470 return ERROR_JTAG_INIT_FAILED;
473 /* set 16mA drive strength */
474 pads_base[BCM2835_PADS_GPIO_0_27_OFFSET] = 0x5a000018 + 7;
476 tdo_gpio_mode = MODE_GPIO(tdo_gpio);
477 tdi_gpio_mode = MODE_GPIO(tdi_gpio);
478 tck_gpio_mode = MODE_GPIO(tck_gpio);
479 tms_gpio_mode = MODE_GPIO(tms_gpio);
480 swclk_gpio_mode = MODE_GPIO(swclk_gpio);
481 swdio_gpio_mode = MODE_GPIO(swdio_gpio);
483 * Configure TDO as an input, and TDI, TCK, TMS, TRST, SRST
484 * as outputs. Drive TDI and TCK low, and TMS/TRST/SRST high.
488 GPIO_CLR = 1<<tdi_gpio | 1<<tck_gpio | 1<<swdio_gpio | 1<<swclk_gpio;
489 GPIO_SET = 1<<tms_gpio;
494 OUT_GPIO(swclk_gpio);
495 OUT_GPIO(swdio_gpio);
496 if (trst_gpio != -1) {
497 trst_gpio_mode = MODE_GPIO(trst_gpio);
498 GPIO_SET = 1 << trst_gpio;
501 if (srst_gpio != -1) {
502 srst_gpio_mode = MODE_GPIO(srst_gpio);
503 GPIO_SET = 1 << srst_gpio;
507 LOG_DEBUG("saved pinmux settings: tck %d tms %d tdi %d "
508 "tdo %d trst %d srst %d", tck_gpio_mode, tms_gpio_mode,
509 tdi_gpio_mode, tdo_gpio_mode, trst_gpio_mode, srst_gpio_mode);
512 bcm2835gpio_bitbang.write = bcm2835gpio_swd_write;
513 bitbang_switch_to_swd();
519 static int bcm2835gpio_quit(void)
521 SET_MODE_GPIO(tdo_gpio, tdo_gpio_mode);
522 SET_MODE_GPIO(tdi_gpio, tdi_gpio_mode);
523 SET_MODE_GPIO(tck_gpio, tck_gpio_mode);
524 SET_MODE_GPIO(tms_gpio, tms_gpio_mode);
525 SET_MODE_GPIO(swclk_gpio, swclk_gpio_mode);
526 SET_MODE_GPIO(swdio_gpio, swdio_gpio_mode);
528 SET_MODE_GPIO(trst_gpio, trst_gpio_mode);
530 SET_MODE_GPIO(srst_gpio, srst_gpio_mode);