[Из песочницы] Разгоняем JTAG роутер
/**
* @file
* This driver implements a bitbang jtag interface using gpio lines via
* router ob BCM63XX SoC.
* The aim of this driver implementation is use system GPIOs but avoid the
* need for a additional kernel driver.
* (Note memory mapped IO is another option, however it doesn't mix well with
* the kernel gpiolib driver - which makes sense I guess.)
*
* A gpio is required for tck, tms, tdi and tdo. One or both of srst and trst
* must be also be specified. The required jtag gpios are specified via the
* bcm63xx_gpio_jtag_nums command or the relevant bcm63xx_gpio_XXX_num commang.
* The srst and trst gpios are set via the bcm63xx_gpio_srst_num and
* bcm63xx_gpio_trst_num respectively. GPIO numbering follows the kernel
* convention of starting from 0.
*
* The gpios should not be in use by another entity, and must not be requested
* by a kernel driver without also being exported by it (otherwise they can't
* be exported by bcm63xx_).
*
* The bcm63xx gpio interface can only manipulate one gpio at a time, so the
* bitbang write handler remembers the last state for tck, tms, tdi to avoid
* superfluous writes.
* For speed the bcm63xx "value" entry is opened at init and held open.
* This results in considerable gains over open-write-close (45s vs 900s)
*
* Further work could address:
* -srst and trst open drain/ push pull
* -configurable active high/low for srst & trst
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include
#include "bitbang.h"
#include
/*
* Helper func to determine if gpio number valid
*
* Assume here that there will be less than 1000 gpios on a system
*/
static int is_gpio_valid(int gpio)
{
return gpio >= 0 && gpio < 32;
}
off_t address_dir = NULL;
off_t address_val = NULL;
static int dev_mem_fd = -1;
static volatile uint32_t *pio_base = NULL;
static volatile uint32_t *pval_base = NULL;
static volatile uint32_t *pads_base = NULL;
static unsigned int jtag_delay = 0;
static void set_dir_gpio(const int gpio, const int direction)
{
if(direction)
*pio_base |= 1 << gpio;
else
*pio_base &= ~(1 << gpio);
}
static void set_value_gpio(const int gpio, const int value)
{
if(value)
*pval_base |= 1 << gpio;
else
*pval_base &= ~(1 << gpio);
for (unsigned int i = 0; i < jtag_delay; i++)
asm volatile ("");
}
static int read_gpio(const int gpio)
{
uint32_t val = *pval_base & (1 << gpio);
val = val ? 1 : 0;
return val;
}
static int setup_bcm63xx_gpio(int gpio, int is_output, int init_high)
{
char buf[40];
char gpiostr[4];
int ret;
if (!is_gpio_valid(gpio))
return ERROR_OK;
if((address_dir == NULL) || (address_val == NULL)){
perror("address of gpio register don't set");
return ERROR_FAIL;
}
if( dev_mem_fd < 0 )
{
dev_mem_fd = open("/dev/mem", O_RDWR | O_SYNC);
if (dev_mem_fd < 0) {
perror("open");
return ERROR_FAIL;
}
const uint32_t mapped_size = getpagesize();
const off_t target_mmap = address_dir & ~(off_t)(mapped_size - 1);
pads_base = mmap(NULL, mapped_size, PROT_READ | PROT_WRITE,
MAP_SHARED, dev_mem_fd, target_mmap);
if (pads_base == MAP_FAILED) {
perror("mmap. Check correct register address.");
close(dev_mem_fd);
return ERROR_FAIL;
}
pio_base = (char*)pads_base + (unsigned)(address_dir - target_mmap);
pval_base = (char*)pads_base + (unsigned)(address_val - target_mmap);
}
set_dir_gpio(gpio, is_output);
set_value_gpio(gpio, init_high);
return 0;
}
/* gpio numbers for each gpio. Negative values are invalid */
static int tck_gpio = -1;
static int tms_gpio = -1;
static int tdi_gpio = -1;
static int tdo_gpio = -1;
static int trst_gpio = -1;
static int srst_gpio = -1;
static int swclk_gpio = -1;
static int swdio_gpio = -1;
/*
* file descriptors for /sys/class/gpio/gpioXX/value
* Set up during init.
*/
static int tck_fd = -1;
static int tms_fd = -1;
static int tdi_fd = -1;
static int tdo_fd = -1;
static int trst_fd = -1;
static int srst_fd = -1;
static int swclk_fd = -1;
static int swdio_fd = -1;
static int last_swclk;
static int last_swdio;
static bool last_stored;
static bool swdio_input;
static void bcm63xx_gpio_swdio_drive(bool is_output)
{
set_dir_gpio(swdio_gpio, is_output ? 1 : 0);
last_stored = false;
swdio_input = !is_output;
}
static int bcm63xx_gpio_swdio_read(void)
{
return read_gpio(swdio_gpio);
}
static void bcm63xx_gpio_swdio_write(int swclk, int swdio)
{
const char one[] = "1";
const char zero[] = "0";
size_t bytes_written;
if (!swdio_input) {
if (!last_stored || (swdio != last_swdio)) {
set_value_gpio(swdio_gpio, swdio ? 1 : 0);
}
}
/* write swclk last */
if (!last_stored || (swclk != last_swclk)) {
set_value_gpio(swclk_gpio, swclk ? 1 : 0);
}
last_swdio = swdio;
last_swclk = swclk;
last_stored = true;
}
/*
* Bitbang interface read of TDO
*
* The bcm63xx value will read back either '0' or '1'. The trick here is to call
* lseek to bypass buffering in the bcm63xx kernel driver.
*/
static int bcm63xx_gpio_read(void)
{
return read_gpio(tdo_gpio);
}
/*
* Bitbang interface write of TCK, TMS, TDI
*
* Seeing as this is the only function where the outputs are changed,
* we can cache the old value to avoid needlessly writing it.
*/
static void bcm63xx_gpio_write(int tck, int tms, int tdi)
{
if (swd_mode) {
bcm63xx_gpio_swdio_write(tck, tdi);
return;
}
const char one[] = "1";
const char zero[] = "0";
static int last_tck;
static int last_tms;
static int last_tdi;
static int first_time;
size_t bytes_written;
if (!first_time) {
last_tck = !tck;
last_tms = !tms;
last_tdi = !tdi;
first_time = 1;
}
if (tdi != last_tdi) {
set_value_gpio(tdi_gpio,tdi);
}
if (tms != last_tms) {
set_value_gpio(tms_gpio,tms);
}
/* write clk last */
if (tck != last_tck) {
set_value_gpio(tck_gpio,tck);
}
last_tdi = tdi;
last_tms = tms;
last_tck = tck;
}
/*
* Bitbang interface to manipulate reset lines SRST and TRST
*
* (1) assert or (0) deassert reset lines
*/
static void bcm63xx_gpio_reset(int trst, int srst)
{
LOG_DEBUG("bcm63xx_gpio_reset");
const char one[] = "1";
const char zero[] = "0";
size_t bytes_written;
/* assume active low */
if (srst_fd >= 0) {
set_value_gpio(srst_gpio,srst);
}
/* assume active low */
if (trst_fd >= 0) {
set_value_gpio(trst_gpio,trst);
}
}
COMMAND_HANDLER(bcm63xx_gpio_handle_jtag_gpionums)
{
if (CMD_ARGC == 4) {
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tck_gpio);
COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], tms_gpio);
COMMAND_PARSE_NUMBER(int, CMD_ARGV[2], tdi_gpio);
COMMAND_PARSE_NUMBER(int, CMD_ARGV[3], tdo_gpio);
} else if (CMD_ARGC != 0) {
return ERROR_COMMAND_SYNTAX_ERROR;
}
command_print(CMD_CTX,
"bcm63xx_GPIO nums: tck = %d, tms = %d, tdi = %d, tdo = %d",
tck_gpio, tms_gpio, tdi_gpio, tdo_gpio);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_handle_jtag_gpionum_tck)
{
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tck_gpio);
command_print(CMD_CTX, "bcm63xx_GPIO num: tck = %d", tck_gpio);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_handle_jtag_gpionum_tms)
{
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tms_gpio);
command_print(CMD_CTX, "bcm63xx_GPIO num: tms = %d", tms_gpio);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_handle_jtag_gpionum_tdo)
{
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tdo_gpio);
command_print(CMD_CTX, "bcm63xx_GPIO num: tdo = %d", tdo_gpio);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_handle_jtag_gpionum_tdi)
{
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tdi_gpio);
command_print(CMD_CTX, "bcm63xx_GPIO num: tdi = %d", tdi_gpio);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_handle_jtag_gpionum_srst)
{
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], srst_gpio);
command_print(CMD_CTX, "bcm63xx_GPIO num: srst = %d", srst_gpio);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_handle_jtag_gpionum_trst)
{
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], trst_gpio);
command_print(CMD_CTX, "bcm63xx_GPIO num: trst = %d", trst_gpio);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_handle_swd_gpionums)
{
if (CMD_ARGC == 2) {
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swclk_gpio);
COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], swdio_gpio);
} else if (CMD_ARGC != 0) {
return ERROR_COMMAND_SYNTAX_ERROR;
}
command_print(CMD_CTX,
"bcm63xx_GPIO nums: swclk = %d, swdio = %d",
swclk_gpio, swdio_gpio);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_handle_swd_gpionum_swclk)
{
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swclk_gpio);
command_print(CMD_CTX, "bcm63xx_GPIO num: swclk = %d", swclk_gpio);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_handle_swd_gpionum_swdio)
{
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swdio_gpio);
command_print(CMD_CTX, "bcm63xx_GPIO num: swdio = %d", swdio_gpio);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_jtag_delay)
{
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], jtag_delay);
command_print(CMD_CTX, "bcm63xx_GPIO jtag_delay:= %d tics", jtag_delay);
return ERROR_OK;
}
COMMAND_HANDLER(bcm63xx_gpio_adresses)
{
if (CMD_ARGC == 2) {
COMMAND_PARSE_NUMBER(u32, CMD_ARGV[0], address_dir);
COMMAND_PARSE_NUMBER(u32, CMD_ARGV[1], address_val);
} else if (CMD_ARGC != 0) {
return ERROR_COMMAND_SYNTAX_ERROR;
}
command_print(CMD_CTX,
"bcm63xx_GPIO address: direction = %x, value = %x",
address_dir, address_val);
return ERROR_OK;
}
static const struct command_registration bcm63xx_gpio_command_handlers[] = {
{
.name = "bcm63xx_gpio_jtag_nums",
.handler = &bcm63xx_gpio_handle_jtag_gpionums,
.mode = COMMAND_CONFIG,
.help = "gpio numbers for tck, tms, tdi, tdo. (in that order)",
.usage = "(tck tms tdi tdo)* ",
},
{
.name = "bcm63xx_gpio_tck_num",
.handler = &bcm63xx_gpio_handle_jtag_gpionum_tck,
.mode = COMMAND_CONFIG,
.help = "gpio number for tck.",
},
{
.name = "bcm63xx_gpio_tms_num",
.handler = &bcm63xx_gpio_handle_jtag_gpionum_tms,
.mode = COMMAND_CONFIG,
.help = "gpio number for tms.",
},
{
.name = "bcm63xx_gpio_tdo_num",
.handler = &bcm63xx_gpio_handle_jtag_gpionum_tdo,
.mode = COMMAND_CONFIG,
.help = "gpio number for tdo.",
},
{
.name = "bcm63xx_gpio_tdi_num",
.handler = &bcm63xx_gpio_handle_jtag_gpionum_tdi,
.mode = COMMAND_CONFIG,
.help = "gpio number for tdi.",
},
{
.name = "bcm63xx_gpio_srst_num",
.handler = &bcm63xx_gpio_handle_jtag_gpionum_srst,
.mode = COMMAND_CONFIG,
.help = "gpio number for srst.",
},
{
.name = "bcm63xx_gpio_trst_num",
.handler = &bcm63xx_gpio_handle_jtag_gpionum_trst,
.mode = COMMAND_CONFIG,
.help = "gpio number for trst.",
},
{
.name = "bcm63xx_gpio_swd_nums",
.handler = &bcm63xx_gpio_handle_swd_gpionums,
.mode = COMMAND_CONFIG,
.help = "gpio numbers for swclk, swdio. (in that order)",
.usage = "(swclk swdio)* ",
},
{
.name = "bcm63xx_gpio_swclk_num",
.handler = &bcm63xx_gpio_handle_swd_gpionum_swclk,
.mode = COMMAND_CONFIG,
.help = "gpio number for swclk.",
},
{
.name = "bcm63xx_gpio_swdio_num",
.handler = &bcm63xx_gpio_handle_swd_gpionum_swdio,
.mode = COMMAND_CONFIG,
.help = "gpio number for swdio.",
},
{
.name = "bcm63xx_gpio_jtag_delay",
.handler = &bcm63xx_gpio_jtag_delay,
.mode = COMMAND_CONFIG,
.help = "qty tics gpio delay.",
},
{
.name = "bcm63xx_gpio_adresses",
.handler = &bcm63xx_gpio_adresses,
.mode = COMMAND_CONFIG,
.help = "addresses for direction and value setup. (in that order)",
.usage = "(address_dir address_val)* ",
},
COMMAND_REGISTRATION_DONE
};
static int bcm63xx_gpio_init(void);
static int bcm63xx_gpio_quit(void);
static const char * const bcm63xx_gpio_transports[] = { "jtag", "swd", NULL };
struct jtag_interface bcm63xxgpio_interface = {
.name = "bcm63xxgpio",
.supported = DEBUG_CAP_TMS_SEQ,
.execute_queue = bitbang_execute_queue,
.transports = bcm63xx_gpio_transports,
.swd = &bitbang_swd,
.commands = bcm63xx_gpio_command_handlers,
.init = bcm63xx_gpio_init,
.quit = bcm63xx_gpio_quit,
};
static struct bitbang_interface bcm63xx_gpio_bitbang = {
.read = bcm63xx_gpio_read,
.write = bcm63xx_gpio_write,
.reset = bcm63xx_gpio_reset,
.swdio_read = bcm63xx_gpio_swdio_read,
.swdio_drive = bcm63xx_gpio_swdio_drive,
.blink = 0
};
static void unusing_all_gpio(void)
{
munmap(pads_base, sysconf(_SC_PAGE_SIZE));
close(dev_mem_fd);
LOG_INFO("unusing_all_gpio\n");
}
static bool bcm63xx_gpio_jtag_mode_possible(void)
{
if (!is_gpio_valid(tck_gpio))
return 0;
if (!is_gpio_valid(tms_gpio))
return 0;
if (!is_gpio_valid(tdi_gpio))
return 0;
if (!is_gpio_valid(tdo_gpio))
return 0;
return 1;
}
static bool bcm63xx_gpio_swd_mode_possible(void)
{
if (!is_gpio_valid(swclk_gpio))
return 0;
if (!is_gpio_valid(swdio_gpio))
return 0;
return 1;
}
static int bcm63xx_gpio_init(void)
{
bitbang_interface = &bcm63xx_gpio_bitbang;
LOG_INFO("bcm63xx_gpio JTAG/SWD bitbang driver");
if (bcm63xx_gpio_jtag_mode_possible()) {
if (bcm63xx_gpio_swd_mode_possible())
LOG_INFO("JTAG and SWD modes enabled");
else
LOG_INFO("JTAG only mode enabled (specify swclk and swdio gpio to add SWD mode)");
if (!is_gpio_valid(trst_gpio) && !is_gpio_valid(srst_gpio)) {
LOG_ERROR("Require at least one of trst or srst gpios to be specified");
return ERROR_JTAG_INIT_FAILED;
}
} else if (bcm63xx_gpio_swd_mode_possible()) {
LOG_INFO("SWD only mode enabled (specify tck, tms, tdi and tdo gpios to add JTAG mode)");
} else {
LOG_ERROR("Require tck, tms, tdi and tdo gpios for JTAG mode and/or swclk and swdio gpio for SWD mode");
return ERROR_JTAG_INIT_FAILED;
}
/*
* Configure TDO as an input, and TDI, TCK, TMS, TRST, SRST
* as outputs. Drive TDI and TCK low, and TMS/TRST/SRST high.
* For SWD, SWCLK and SWDIO are configures as output high.
*/
if (tck_gpio >= 0) {
tck_fd = setup_bcm63xx_gpio(tck_gpio, 1, 0);
if (tck_fd < 0)
goto out_error;
}
if (tms_gpio >= 0) {
tms_fd = setup_bcm63xx_gpio(tms_gpio, 1, 1);
if (tms_fd < 0)
goto out_error;
}
if (tdi_gpio >= 0) {
tdi_fd = setup_bcm63xx_gpio(tdi_gpio, 1, 0);
if (tdi_fd < 0)
goto out_error;
}
if (tdo_gpio >= 0) {
tdo_fd = setup_bcm63xx_gpio(tdo_gpio, 0, 0);
if (tdo_fd < 0)
goto out_error;
}
/* assume active low*/
if (trst_gpio >= 0) {
trst_fd = setup_bcm63xx_gpio(trst_gpio, 1, 1);
if (trst_fd < 0)
goto out_error;
}
/* assume active low*/
if (srst_gpio >= 0) {
srst_fd = setup_bcm63xx_gpio(srst_gpio, 1, 1);
if (srst_fd < 0)
goto out_error;
}
if (swclk_gpio >= 0) {
swclk_fd = setup_bcm63xx_gpio(swclk_gpio, 1, 0);
if (swclk_fd < 0)
goto out_error;
}
if (swdio_gpio >= 0) {
swdio_fd = setup_bcm63xx_gpio(swdio_gpio, 1, 0);
if (swdio_fd < 0)
goto out_error;
}
if (bcm63xx_gpio_swd_mode_possible()) {
if (swd_mode)
bitbang_swd_switch_seq(JTAG_TO_SWD);
else
bitbang_swd_switch_seq(SWD_TO_JTAG);
}
return ERROR_OK;
out_error:
unusing_all_gpio();
return ERROR_JTAG_INIT_FAILED;
}
static int bcm63xx_gpio_quit(void)
{
unusing_all_gpio();
return ERROR_OK;
}
