zephyr/drivers/watchdog/wdt_nxp_s32.c

415 lines
11 KiB
C

/*
* Copyright 2022-2024 NXP
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT nxp_s32_swt
#include <zephyr/kernel.h>
#include <zephyr/drivers/watchdog.h>
#include <zephyr/drivers/clock_control.h>
#include <zephyr/irq.h>
#define LOG_LEVEL CONFIG_WDT_LOG_LEVEL
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(swt_nxp_s32);
/* Software Watchdog Timer (SWT) register definitions */
/* Control */
#define SWT_CR 0x0
#define SWT_CR_WEN_MASK BIT(0)
#define SWT_CR_WEN(v) FIELD_PREP(SWT_CR_WEN_MASK, (v))
#define SWT_CR_FRZ_MASK BIT(1)
#define SWT_CR_FRZ(v) FIELD_PREP(SWT_CR_FRZ_MASK, (v))
#define SWT_CR_STP_MASK BIT(2)
#define SWT_CR_STP(v) FIELD_PREP(SWT_CR_STP_MASK, (v))
#define SWT_CR_SLK_MASK BIT(4)
#define SWT_CR_SLK(v) FIELD_PREP(SWT_CR_SLK_MASK, (v))
#define SWT_CR_HLK_MASK BIT(5)
#define SWT_CR_HLK(v) FIELD_PREP(SWT_CR_HLK_MASK, (v))
#define SWT_CR_ITR_MASK BIT(6)
#define SWT_CR_ITR(v) FIELD_PREP(SWT_CR_ITR_MASK, (v))
#define SWT_CR_WND_MASK BIT(7)
#define SWT_CR_WND(v) FIELD_PREP(SWT_CR_WND_MASK, (v))
#define SWT_CR_RIA_MASK BIT(8)
#define SWT_CR_RIA(v) FIELD_PREP(SWT_CR_RIA_MASK, (v))
#define SWT_CR_SMD_MASK GENMASK(10, 9)
#define SWT_CR_SMD(v) FIELD_PREP(SWT_CR_SMD_MASK, (v))
#define SWT_CR_MAP_MASK GENMASK(31, 24)
#define SWT_CR_MAP(v) FIELD_PREP(SWT_CR_MAP_MASK, (v))
/* Interrupt */
#define SWT_IR 0x4
#define SWT_IR_TIF_MASK BIT(0)
#define SWT_IR_TIF(v) FIELD_PREP(SWT_IR_TIF_MASK, (v))
/* Timeout */
#define SWT_TO 0x8
#define SWT_TO_WTO_MASK GENMASK(31, 0)
#define SWT_TO_WTO(v) FIELD_PREP(SWT_TO_WTO_MASK, (v))
/* Window */
#define SWT_WN 0xc
#define SWT_WN_WST_MASK GENMASK(31, 0)
#define SWT_WN_WST(v) FIELD_PREP(SWT_WN_WST_MASK, (v))
/* Service */
#define SWT_SR 0x10
#define SWT_SR_WSC_MASK GENMASK(15, 0)
#define SWT_SR_WSC(v) FIELD_PREP(SWT_SR_WSC_MASK, (v))
/* Counter Output */
#define SWT_CO 0x14
#define SWT_CO_CNT_MASK GENMASK(31, 0)
#define SWT_CO_CNT(v) FIELD_PREP(SWT_CO_CNT_MASK, (v))
/* Service Key */
#define SWT_SK 0x18
#define SWT_SK_SK_MASK GENMASK(15, 0)
#define SWT_SK_SK(v) FIELD_PREP(SWT_SK_SK_MASK, (v))
/* Event Request */
#define SWT_RRR 0x1c
#define SWT_RRR_RRF_MASK BIT(0)
#define SWT_RRR_RRF(v) FIELD_PREP(SWT_RRR_RRF_MASK, (v))
#define SWT_TO_WTO_MIN 0x100
#define SWT_SR_WSC_UNLOCK_KEY1 0xC520U
#define SWT_SR_WSC_UNLOCK_KEY2 0xD928U
#define SWT_SR_WSC_SERVICE_KEY1 0xA602U
#define SWT_SR_WSC_SERVICE_KEY2 0xB480U
#define SWT_SOFT_LOCK_TIMEOUT_US 3000
/* Handy accessors */
#define REG_READ(r) sys_read32(config->base + (r))
#define REG_WRITE(r, v) sys_write32((v), config->base + (r))
enum swt_service_mode {
SWT_FIXED_SERVICE = 0,
SWT_KEYED_SERVICE = 1,
};
enum swt_lock_mode {
SWT_UNLOCKED = 0,
SWT_SOFT_LOCK = 1,
SWT_HARD_LOCK = 2,
};
struct swt_nxp_s32_timeout {
uint32_t period;
uint32_t window_start;
bool window_mode;
};
struct swt_nxp_s32_config {
mem_addr_t base;
const struct device *clock_dev;
clock_control_subsys_t clock_subsys;
uint8_t master_access_mask;
enum swt_lock_mode lock_mode;
enum swt_service_mode service_mode;
uint16_t initial_key;
bool reset_on_invalid_access;
};
struct swt_nxp_s32_data {
wdt_callback_t callback;
bool timeout_valid;
struct swt_nxp_s32_timeout timeout;
};
static void swt_lock(const struct swt_nxp_s32_config *config)
{
switch (config->lock_mode) {
case SWT_HARD_LOCK:
REG_WRITE(SWT_CR, REG_READ(SWT_CR) | SWT_CR_HLK(1U));
break;
case SWT_SOFT_LOCK:
REG_WRITE(SWT_CR, REG_READ(SWT_CR) | SWT_CR_SLK(1U));
break;
case SWT_UNLOCKED:
__fallthrough;
default:
break;
}
}
static int swt_unlock(const struct swt_nxp_s32_config *config)
{
int err = 0;
if (FIELD_GET(SWT_CR_HLK_MASK, REG_READ(SWT_CR)) != 0U) {
LOG_ERR("Watchdog hard-locked");
err = -EFAULT;
} else if (FIELD_GET(SWT_CR_SLK_MASK, REG_READ(SWT_CR)) != 0U) {
REG_WRITE(SWT_SR, SWT_SR_WSC(SWT_SR_WSC_UNLOCK_KEY1));
REG_WRITE(SWT_SR, SWT_SR_WSC(SWT_SR_WSC_UNLOCK_KEY2));
if (!WAIT_FOR(FIELD_GET(SWT_CR_SLK_MASK, REG_READ(SWT_CR) != 0),
SWT_SOFT_LOCK_TIMEOUT_US, NULL)) {
LOG_ERR("Timedout while trying to unlock");
err = -ETIMEDOUT;
/* make sure is locked again before we leave */
REG_WRITE(SWT_CR, REG_READ(SWT_CR) | SWT_CR_SLK(1U));
}
}
return err;
}
static inline uint16_t swt_gen_service_key(const struct swt_nxp_s32_config *config)
{
/* Calculated pseudo-random key according to Service Key Generation chapter in RM */
return (uint16_t)((FIELD_GET(SWT_SK_SK_MASK, REG_READ(SWT_SK)) * 17U) + 3U);
}
static int swt_nxp_s32_setup(const struct device *dev, uint8_t options)
{
const struct swt_nxp_s32_config *config = dev->config;
struct swt_nxp_s32_data *data = dev->data;
int err;
uint32_t reg_val;
if (!data->timeout_valid) {
LOG_ERR("No valid timeouts installed");
return -EINVAL;
}
err = swt_unlock(config);
if (err) {
return err;
}
reg_val = REG_READ(SWT_CR);
reg_val &= ~(SWT_CR_WND_MASK | SWT_CR_STP_MASK | SWT_CR_FRZ_MASK | SWT_CR_ITR_MASK);
REG_WRITE(SWT_CR, reg_val |
SWT_CR_WND(data->timeout.window_mode ? 1U : 0U) |
SWT_CR_ITR(data->callback ? 1U : 0U) |
SWT_CR_STP((options & WDT_OPT_PAUSE_IN_SLEEP) ? 1U : 0U) |
SWT_CR_FRZ((options & WDT_OPT_PAUSE_HALTED_BY_DBG) ? 1U : 0U));
REG_WRITE(SWT_IR, SWT_IR_TIF(1U));
REG_WRITE(SWT_TO, SWT_TO_WTO(data->timeout.period));
REG_WRITE(SWT_WN, SWT_WN_WST(data->timeout.window_start));
if (config->service_mode == SWT_KEYED_SERVICE) {
REG_WRITE(SWT_SK, SWT_SK_SK(config->initial_key));
}
REG_WRITE(SWT_CR, REG_READ(SWT_CR) | SWT_CR_WEN(1U));
swt_lock(config);
return 0;
}
static int swt_nxp_s32_disable(const struct device *dev)
{
const struct swt_nxp_s32_config *config = dev->config;
struct swt_nxp_s32_data *data = dev->data;
int err;
if (!FIELD_GET(SWT_CR_WEN_MASK, REG_READ(SWT_CR))) {
LOG_ERR("Watchdog is not enabled");
return -EFAULT;
}
err = swt_unlock(config);
if (err) {
return err;
}
/* Disable the watchdog and clear interrupt flags */
REG_WRITE(SWT_CR, REG_READ(SWT_CR) & ~SWT_CR_WEN_MASK);
REG_WRITE(SWT_IR, SWT_IR_TIF(1U));
swt_lock(config);
data->timeout_valid = false;
return 0;
}
static int swt_nxp_s32_install_timeout(const struct device *dev,
const struct wdt_timeout_cfg *cfg)
{
const struct swt_nxp_s32_config *config = dev->config;
struct swt_nxp_s32_data *data = dev->data;
bool window_mode = false;
uint32_t window = 0;
uint32_t period;
uint32_t clock_rate;
int err;
if (data->timeout_valid) {
LOG_ERR("No more timeouts can be installed");
return -ENOMEM;
}
err = clock_control_get_rate(config->clock_dev, config->clock_subsys, &clock_rate);
if (err) {
LOG_ERR("Failed to get module clock frequency");
return err;
}
period = clock_rate / 1000U * cfg->window.max;
if (cfg->window.min) {
window_mode = true;
window = clock_rate / 1000U * (cfg->window.max - cfg->window.min);
}
if ((period < SWT_TO_WTO_MIN) || (period < window)) {
LOG_ERR("Invalid timeout");
return -EINVAL;
}
data->timeout.period = period;
data->timeout.window_start = window;
data->timeout.window_mode = window_mode;
data->callback = cfg->callback;
data->timeout_valid = true;
LOG_DBG("Installed timeout: period=%d, window=%d (%s)",
period, window, window_mode ? "enabled" : "disabled");
return 0;
}
static int swt_nxp_s32_feed(const struct device *dev, int channel)
{
const struct swt_nxp_s32_config *config = dev->config;
bool match_unlock_seq = false;
int err = 0;
ARG_UNUSED(channel);
switch (config->service_mode) {
case SWT_FIXED_SERVICE:
REG_WRITE(SWT_SR, SWT_SR_WSC(SWT_SR_WSC_SERVICE_KEY1));
REG_WRITE(SWT_SR, SWT_SR_WSC(SWT_SR_WSC_SERVICE_KEY2));
break;
case SWT_KEYED_SERVICE:
/*
* If one or more service routines use both unlock keys in the proper order,
* the watchdog unlocks the soft lock
*/
if (swt_gen_service_key(config) == SWT_SR_WSC_UNLOCK_KEY1) {
match_unlock_seq = true;
}
REG_WRITE(SWT_SR, SWT_SR_WSC(swt_gen_service_key(config)));
if (swt_gen_service_key(config) == SWT_SR_WSC_UNLOCK_KEY1) {
match_unlock_seq = true;
}
REG_WRITE(SWT_SR, SWT_SR_WSC(swt_gen_service_key(config)));
if (match_unlock_seq && (config->lock_mode == SWT_SOFT_LOCK)) {
/*
* Service key generated matched the unlock sequence, complete the
* unlock sequence and reinitiate the soft lock
*/
REG_WRITE(SWT_SR, SWT_SR_WSC(SWT_SR_WSC_UNLOCK_KEY2));
swt_lock(config);
}
break;
default:
LOG_ERR("Invalid service mode");
err = -EINVAL;
break;
}
LOG_DBG("Fed the watchdog");
return err;
}
static void swt_nxp_s32_isr(const struct device *dev)
{
const struct swt_nxp_s32_config *config = dev->config;
struct swt_nxp_s32_data *data = dev->data;
uint32_t reg_val;
if (FIELD_GET(SWT_IR_TIF_MASK, REG_READ(SWT_IR)) &&
FIELD_GET(SWT_CR_ITR_MASK, REG_READ(SWT_CR))) {
/* Clear interrupt flag */
reg_val = REG_READ(SWT_IR);
reg_val &= SWT_IR_TIF_MASK;
REG_WRITE(SWT_IR, reg_val);
if (data->callback) {
/* SWT only has one channel */
data->callback(dev, 0U);
}
}
}
static int swt_nxp_s32_init(const struct device *dev)
{
const struct swt_nxp_s32_config *config = dev->config;
int err;
if (!device_is_ready(config->clock_dev)) {
return -ENODEV;
}
err = clock_control_on(config->clock_dev, config->clock_subsys);
if (err) {
return err;
}
REG_WRITE(SWT_CR,
SWT_CR_MAP(config->master_access_mask) |
SWT_CR_RIA(config->reset_on_invalid_access) |
SWT_CR_SMD(config->service_mode));
return 0;
}
static const struct wdt_driver_api swt_nxp_s32_driver_api = {
.setup = swt_nxp_s32_setup,
.disable = swt_nxp_s32_disable,
.install_timeout = swt_nxp_s32_install_timeout,
.feed = swt_nxp_s32_feed,
};
#define SWT_NXP_S32_DEVICE_INIT(n) \
static struct swt_nxp_s32_data swt_nxp_s32_data_##n; \
\
static const struct swt_nxp_s32_config swt_nxp_s32_config_##n = { \
.base = DT_INST_REG_ADDR(n), \
.clock_dev = DEVICE_DT_GET(DT_INST_CLOCKS_CTLR(n)), \
.clock_subsys = (clock_control_subsys_t)DT_INST_CLOCKS_CELL(n, name), \
.master_access_mask = DT_INST_PROP(n, master_access_mask), \
.reset_on_invalid_access = DT_INST_PROP(n, reset_on_invalid_access), \
.service_mode = DT_INST_ENUM_IDX(n, service_mode), \
.initial_key = (uint16_t)DT_INST_PROP(n, initial_key), \
.lock_mode = DT_INST_ENUM_IDX(n, lock_mode), \
}; \
\
static int swt_nxp_s32_##n##_init(const struct device *dev) \
{ \
int err; \
\
err = swt_nxp_s32_init(dev); \
if (err) { \
return err; \
} \
\
IRQ_CONNECT(DT_INST_IRQN(n), DT_INST_IRQ(n, priority), \
swt_nxp_s32_isr, DEVICE_DT_INST_GET(n), \
COND_CODE_1(DT_INST_IRQ_HAS_CELL(n, flags), \
(DT_INST_IRQ(n, flags)), (0))); \
irq_enable(DT_INST_IRQN(n)); \
\
return 0; \
} \
\
DEVICE_DT_INST_DEFINE(n, \
swt_nxp_s32_##n##_init, \
NULL, \
&swt_nxp_s32_data_##n, \
&swt_nxp_s32_config_##n, \
POST_KERNEL, \
CONFIG_KERNEL_INIT_PRIORITY_DEVICE, \
&swt_nxp_s32_driver_api);
DT_INST_FOREACH_STATUS_OKAY(SWT_NXP_S32_DEVICE_INIT)