parport.c

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// SPDX-License-Identifier: GPL-2.0-or-later
 
/***************************************************************************
 *   Copyright (C) 2005 by Dominic Rath                                    *
 *   Dominic.Rath@gmx.de                                                   *
 *                                                                         *
 *   Copyright (C) 2008 by Spencer Oliver                                  *
 *   spen@spen-soft.co.uk                                                  *
 ***************************************************************************/
 
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
 
#include <jtag/adapter.h>
#include <jtag/interface.h>
#include "bitbang.h"
 
/* -ino: 060521-1036 */
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
#include <machine/sysarch.h>
#include <machine/cpufunc.h>
#define ioperm(startport, length, enable) \
    i386_set_ioperm((startport), (length), (enable))
#endif /* __FreeBSD__ */
 
#if PARPORT_USE_PPDEV == 1
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
#include <dev/ppbus/ppi.h>
#include <dev/ppbus/ppbconf.h>
#define PPRSTATUS   PPIGSTATUS
#define PPWDATA     PPISDATA
#else
#include <linux/parport.h>
#include <linux/ppdev.h>
#endif
#include <sys/ioctl.h>
#else /* not PARPORT_USE_PPDEV */
#ifndef _WIN32
#include <sys/io.h>
#endif
#endif
 
#if PARPORT_USE_GIVEIO == 1 && IS_CYGWIN == 1
#include <windows.h>
#endif
 
static const struct adapter_gpio_config *adapter_gpio_config;
 
static uint16_t parport_port;
static bool parport_write_exit_state;
static uint32_t parport_toggling_time_ns = 1000;
static int wait_states;
 
// Interface variables.
static uint8_t dataport_value;
 
#if PARPORT_USE_PPDEV == 1
static int device_handle;
#else
static unsigned long dataport;
static unsigned long statusport;
#endif
 
// Bitmask map for the input pins.
static struct {
    uint8_t mask;
} input_pin_bitmask_map[] = {
    [10] = {0x40},
    [11] = {0x80},
    [12] = {0x20},
    [13] = {0x10},
    [15] = {0x08},
};
 
// Generate an output pin bitmask for an adapter signal.
#define OUTPUT_BITMASK(gpio_index) BIT((adapter_gpio_config[(gpio_index)].gpio_num - 2))
 
static enum bb_value parport_read(void)
{
    int data = 0;
 
#if PARPORT_USE_PPDEV == 1
    ioctl(device_handle, PPRSTATUS, &data);
#else
    data = inb(statusport);
#endif
 
    const struct adapter_gpio_config *gpio_config = &adapter_gpio_config[ADAPTER_GPIO_IDX_TDO];
    const bool tdo_state = data & input_pin_bitmask_map[gpio_config->gpio_num].mask;
 
    return (tdo_state ^ gpio_config->active_low) ? BB_HIGH : BB_LOW;
}
 
static void parport_write_data(void)
{
    const uint8_t output = dataport_value;
 
#if PARPORT_USE_PPDEV == 1
    ioctl(device_handle, PPWDATA, &output);
#else
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
    outb(dataport, output);
#else
    outb(output, dataport);
#endif
#endif
}
 
static bool is_gpio_configured(enum adapter_gpio_config_index gpio_index)
{
    return adapter_gpio_config[gpio_index].gpio_num != ADAPTER_GPIO_NOT_SET;
}
 
static void set_pin_state(enum adapter_gpio_config_index gpio_index,
    bool state)
{
    if (state ^ adapter_gpio_config[gpio_index].active_low)
        dataport_value |= OUTPUT_BITMASK(gpio_index);
    else
        dataport_value &= ~OUTPUT_BITMASK(gpio_index);
}
 
static int parport_write(int tck, int tms, int tdi)
{
    set_pin_state(ADAPTER_GPIO_IDX_TCK, tck == 1);
    set_pin_state(ADAPTER_GPIO_IDX_TMS, tms == 1);
    set_pin_state(ADAPTER_GPIO_IDX_TDI, tdi == 1);
 
    for (int i = 0; i < wait_states + 1; i++)
        parport_write_data();
 
    return ERROR_OK;
}
 
// (1) assert or (0) deassert reset lines.
static int parport_reset(int trst, int srst)
{
    LOG_DEBUG("trst: %i, srst: %i", trst, srst);
 
    if (is_gpio_configured(ADAPTER_GPIO_IDX_TRST))
        set_pin_state(ADAPTER_GPIO_IDX_TRST, trst == 0);
 
    if (is_gpio_configured(ADAPTER_GPIO_IDX_SRST))
        set_pin_state(ADAPTER_GPIO_IDX_SRST, srst == 0);
 
    parport_write_data();
 
    return ERROR_OK;
}
 
static int parport_led(bool on)
{
    if (!is_gpio_configured(ADAPTER_GPIO_IDX_LED))
        return ERROR_OK;
 
    set_pin_state(ADAPTER_GPIO_IDX_LED, on);
    parport_write_data();
 
    return ERROR_OK;
}
 
static int parport_speed(int speed)
{
    wait_states = speed;
    return ERROR_OK;
}
 
static int parport_khz(int khz, int *jtag_speed)
{
    if (!khz) {
        LOG_ERROR("RCLK is not supported by the adapter");
        return ERROR_FAIL;
    }
 
    *jtag_speed = 499999 / (khz * parport_toggling_time_ns);
 
    return ERROR_OK;
}
 
static int parport_speed_div(int speed, int *khz)
{
    uint32_t denominator = (speed + 1) * parport_toggling_time_ns;
 
    *khz = (499999 + denominator) / denominator;
 
    return ERROR_OK;
}
 
#if PARPORT_USE_GIVEIO == 1
static bool parport_get_giveio_access(void)
{
    OSVERSIONINFO version;
 
    version.dwOSVersionInfoSize = sizeof(version);
    if (!GetVersionEx(&version)) {
        errno = EINVAL;
        return false;
    }
 
    if (version.dwPlatformId != VER_PLATFORM_WIN32_NT)
        return true;
 
    HANDLE h = CreateFile("\\\\.\\giveio", GENERIC_READ, 0, NULL, OPEN_EXISTING,
        FILE_ATTRIBUTE_NORMAL, NULL);
 
    if (h == INVALID_HANDLE_VALUE) {
        errno = ENODEV;
        return false;
    }
 
    CloseHandle(h);
 
    return true;
}
#endif
 
static const struct bitbang_interface parport_bitbang = {
    .read = &parport_read,
    .write = &parport_write,
    .blink = &parport_led,
};
 
static const struct {
    enum adapter_gpio_config_index gpio_index;
    bool required;
} all_signals[] = {
    { ADAPTER_GPIO_IDX_TDO, true },
    { ADAPTER_GPIO_IDX_TDI, true },
    { ADAPTER_GPIO_IDX_TMS, true },
    { ADAPTER_GPIO_IDX_TCK, true },
    { ADAPTER_GPIO_IDX_TRST, false },
    { ADAPTER_GPIO_IDX_SRST, false },
    { ADAPTER_GPIO_IDX_LED, false },
    { ADAPTER_GPIO_IDX_USER0, false },
};
 
static int parport_init(void)
{
    adapter_gpio_config = adapter_gpio_get_config();
 
    // Check if all signals are configured properly.
    for (size_t i = 0; i < ARRAY_SIZE(all_signals); i++) {
        const enum adapter_gpio_config_index gpio_index = all_signals[i].gpio_index;
        const struct adapter_gpio_config gpio = adapter_gpio_config[gpio_index];
 
        if (gpio.gpio_num == ADAPTER_GPIO_NOT_SET) {
            if (all_signals[i].required) {
                LOG_ERROR("The signal '%s' is required and must be configured",
                    adapter_gpio_get_name(gpio_index));
                return ERROR_FAIL;
            }
 
            continue;
        }
 
        if (gpio_index == ADAPTER_GPIO_IDX_TDO) {
            if (gpio.gpio_num < 10 || gpio.gpio_num > 15 || gpio.gpio_num == 14) {
                LOG_ERROR("The '%s' signal pin must be 10, 11, 12, 13, or 15",
                    adapter_gpio_get_name(gpio_index));
                return ERROR_FAIL;
            }
        } else {
            if (gpio.gpio_num < 2 || gpio.gpio_num > 9) {
                LOG_ERROR("The '%s' signal pin must be 2, 3, 4, 5, 6, 7, 8, or 9",
                    adapter_gpio_get_name(gpio_index));
                return ERROR_FAIL;
            }
        }
    }
 
    // Initialize signal pin states.
    for (size_t i = 0; i < ARRAY_SIZE(all_signals); i++) {
        const enum adapter_gpio_config_index gpio_index = all_signals[i].gpio_index;
        const struct adapter_gpio_config gpio = adapter_gpio_config[gpio_index];
 
        // The TDO (input) and LED (controlled by the adapter) pins cannot be
        // initialized.
        if (gpio_index == ADAPTER_GPIO_IDX_TDO || gpio_index == ADAPTER_GPIO_IDX_LED)
            continue;
 
        // Do not initialize unconfigured GPIO pins.
        if (gpio.gpio_num == ADAPTER_GPIO_NOT_SET)
            continue;
 
        if (gpio.init_state == ADAPTER_GPIO_INIT_STATE_ACTIVE)
            set_pin_state(gpio_index, true);
        else if (gpio.init_state == ADAPTER_GPIO_INIT_STATE_INACTIVE)
            set_pin_state(gpio_index, false);
    }
 
#if PARPORT_USE_PPDEV == 1
    if (device_handle > 0) {
        LOG_ERROR("Parallel port is already open");
        return ERROR_JTAG_INIT_FAILED;
    }
 
    char device_path[256];
 
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
    snprintf(device_path, sizeof(device_path), "/dev/ppi%d", parport_port);
#else
    snprintf(device_path, sizeof(device_path), "/dev/parport%d", parport_port);
#endif /* __FreeBSD__, __FreeBSD_kernel__ */
 
    LOG_DEBUG("Using parallel port %s", device_path);
 
    device_handle = open(device_path, O_WRONLY);
 
    if (device_handle < 0) {
        int err = errno;
        LOG_ERROR("Failed to open parallel port %s (errno = %d)", device_path,
            err);
        LOG_ERROR("Check whether the device exists and if you have the required access rights");
        return ERROR_JTAG_INIT_FAILED;
    }
 
#if !defined(__FreeBSD__) && !defined(__FreeBSD_kernel__)
    int retval = ioctl(device_handle, PPCLAIM);
 
    if (retval < 0) {
        LOG_ERROR("Failed to claim parallel port %s", device_path);
        return ERROR_JTAG_INIT_FAILED;
    }
 
    int value = PARPORT_MODE_COMPAT;
    retval = ioctl(device_handle, PPSETMODE, &value);
 
    if (retval < 0) {
        LOG_ERROR("Cannot set compatible mode to device");
        return ERROR_JTAG_INIT_FAILED;
    }
 
    value = IEEE1284_MODE_COMPAT;
    retval = ioctl(device_handle, PPNEGOT, &value);
 
    if (retval < 0) {
        LOG_ERROR("Cannot set compatible 1284 mode to device");
        return ERROR_JTAG_INIT_FAILED;
    }
#endif /* not __FreeBSD__, __FreeBSD_kernel__ */
 
#else /* not PARPORT_USE_PPDEV */
    if (!parport_port) {
        parport_port = 0x378;
        LOG_WARNING("No parallel port specified, using default 0x378 (LPT1)");
    }
 
    LOG_DEBUG("Using parallel port 0x%x", parport_port);
 
    dataport = parport_port;
    statusport = parport_port + 1;
 
#if PARPORT_USE_GIVEIO == 1
    if (!parport_get_giveio_access()) {
#else /* PARPORT_USE_GIVEIO */
    if (ioperm(dataport, 3, 1) != 0) {
#endif /* PARPORT_USE_GIVEIO */
        LOG_ERROR("Missing privileges for direct I/O");
        return ERROR_JTAG_INIT_FAILED;
    }
 
    // Make sure parallel port is in right mode (clear tristate and interrupt).
    #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
        outb(parport_port + 2, 0x0);
    #else
        outb(0x0, parport_port + 2);
    #endif
 
#endif /* PARPORT_USE_PPDEV */
 
    if (parport_reset(0, 0) != ERROR_OK)
        return ERROR_FAIL;
 
    if (parport_write(0, 0, 0) != ERROR_OK)
        return ERROR_FAIL;
 
    if (parport_led(true) != ERROR_OK)
        return ERROR_FAIL;
 
    bitbang_interface = &parport_bitbang;
 
    return ERROR_OK;
}
 
static int parport_quit(void)
{
    // Deinitialize signal pin states.
    for (size_t i = 0; i < ARRAY_SIZE(all_signals); i++) {
        const enum adapter_gpio_config_index gpio_index = all_signals[i].gpio_index;
        const struct adapter_gpio_config gpio = adapter_gpio_config[gpio_index];
 
        // The TDO (input) and LED (controlled by the adapter) pins cannot be
        // deinitialized.
        if (gpio_index == ADAPTER_GPIO_IDX_TDO || gpio_index == ADAPTER_GPIO_IDX_LED)
            continue;
 
        // Do not deinitialize unconfigured GPIO pins.
        if (gpio.gpio_num == ADAPTER_GPIO_NOT_SET)
            continue;
 
        if (gpio.exit_state == ADAPTER_GPIO_EXIT_STATE_ACTIVE)
            set_pin_state(gpio_index, true);
        else if (gpio.exit_state == ADAPTER_GPIO_EXIT_STATE_INACTIVE)
            set_pin_state(gpio_index, false);
    }
 
    if (parport_write_exit_state)
        parport_write_data();
 
    if (parport_led(false) != ERROR_OK)
        return ERROR_FAIL;
 
    return ERROR_OK;
}
 
COMMAND_HANDLER(parport_handle_port_command)
{
    if (CMD_ARGC != 1)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    // Only if the port wasn't overwritten by command-line.
    if (parport_port > 0) {
        command_print(CMD, "The parallel port is already configured");
        return ERROR_FAIL;
    }
 
    COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0], parport_port);
 
    return ERROR_OK;
}
 
// This command is only for backward compatibility and will be removed in the
// future.
COMMAND_HANDLER(parport_handle_cable_command)
{
    if (CMD_ARGC != 1)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    return command_run_linef(CMD_CTX, "parport_select_cable %s", CMD_ARGV[0]);
}
 
COMMAND_HANDLER(parport_handle_write_on_exit_command)
{
    if (CMD_ARGC != 1)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    LOG_WARNING("DEPRECATED: 'parport write_on_exit' will be removed in the future, use the 'adapter gpio' command to configure the exit state for pins");
 
    COMMAND_PARSE_ON_OFF(CMD_ARGV[0], parport_write_exit_state);
 
    return ERROR_OK;
}
 
COMMAND_HANDLER(parport_handle_toggling_time_command)
{
    if (CMD_ARGC != 1)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    uint32_t toggling_time;
 
    COMMAND_PARSE_NUMBER(u32, CMD_ARGV[0], toggling_time);
 
    if (!toggling_time) {
        command_print(CMD, "toggling time must not be 0 ns");
        return ERROR_COMMAND_ARGUMENT_INVALID;
    }
 
    parport_toggling_time_ns = toggling_time;
    int retval = adapter_get_speed(&wait_states);
 
    if (retval != ERROR_OK) {
        /*
         * If adapter_get_speed fails then the clock_mode has not been
         * configured, this happens if toggling_time is called before the
         * adapter speed is set.
         */
        LOG_INFO("No parallel port speed set, using zero wait states");
        wait_states = 0;
    }
 
    return ERROR_OK;
}
 
static const struct command_registration parport_subcommand_handlers[] = {
    {
        .name = "port",
        .handler = parport_handle_port_command,
        .mode = COMMAND_CONFIG,
        .help = "Configure the address of the I/O port (e.g. 0x378) "
            "or the number of the '/dev/parport' (Linux) or '/dev/ppi' (FreeBSD) device used",
        .usage = "port_number",
    },
    {
        .name = "cable",
        .handler = parport_handle_cable_command,
        .mode = COMMAND_CONFIG,
        .help = "Set the layout of the parallel port cable "
            "used to connect to the target",
        .usage = "cable",
    },
    {
        .name = "write_on_exit",
        .handler = parport_handle_write_on_exit_command,
        .mode = COMMAND_CONFIG,
        .help = "Configure the driver to write a value to the parallel port on shutdown",
        .usage = "('on'|'off')",
    },
    {
        .name = "toggling_time",
        .handler = parport_handle_toggling_time_command,
        .mode = COMMAND_CONFIG,
        .help = "Configure how many nanoseconds it takes for the hardware to toggle TCK",
        .usage = "time",
    },
    COMMAND_REGISTRATION_DONE
};
 
static const struct command_registration parport_command_handlers[] = {
    {
        .name = "parport",
        .mode = COMMAND_ANY,
        .help = "perform parport management",
        .chain = parport_subcommand_handlers,
        .usage = "",
    },
    COMMAND_REGISTRATION_DONE
};
 
static struct jtag_interface parport_interface = {
    .supported = DEBUG_CAP_TMS_SEQ,
    .execute_queue = bitbang_execute_queue,
};
 
struct adapter_driver parport_adapter_driver = {
    .name = "parport",
    .transport_ids = TRANSPORT_JTAG,
    .transport_preferred_id = TRANSPORT_JTAG,
    .commands = parport_command_handlers,
 
    .init = parport_init,
    .quit = parport_quit,
    .reset = parport_reset,
    .speed = parport_speed,
    .khz = parport_khz,
    .speed_div = parport_speed_div,
 
    .jtag_ops = &parport_interface,
};