zephyr/drivers/serial/uart_npcx.c

567 lines
17 KiB
C

/*
* Copyright (c) 2020 Nuvoton Technology Corporation.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT nuvoton_npcx_uart
#include <zephyr/sys/__assert.h>
#include <zephyr/drivers/gpio.h>
#include <zephyr/drivers/pinctrl.h>
#include <zephyr/drivers/uart.h>
#include <zephyr/drivers/clock_control.h>
#include <zephyr/kernel.h>
#include <zephyr/pm/device.h>
#include <zephyr/pm/policy.h>
#include <soc.h>
#include "soc_miwu.h"
#include "soc_power.h"
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(uart_npcx, CONFIG_UART_LOG_LEVEL);
/* Driver config */
struct uart_npcx_config {
struct uart_reg *inst;
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
uart_irq_config_func_t irq_config_func;
#endif
/* clock configuration */
struct npcx_clk_cfg clk_cfg;
/* int-mux configuration */
const struct npcx_wui uart_rx_wui;
/* pinmux configuration */
const struct pinctrl_dev_config *pcfg;
};
enum uart_pm_policy_state_flag {
UART_PM_POLICY_STATE_TX_FLAG,
UART_PM_POLICY_STATE_RX_FLAG,
UART_PM_POLICY_STATE_FLAG_COUNT,
};
/* Driver data */
struct uart_npcx_data {
/* Baud rate */
uint32_t baud_rate;
struct miwu_dev_callback uart_rx_cb;
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
uart_irq_callback_user_data_t user_cb;
void *user_data;
#endif
#ifdef CONFIG_PM
ATOMIC_DEFINE(pm_policy_state_flag, UART_PM_POLICY_STATE_FLAG_COUNT);
#ifdef CONFIG_UART_CONSOLE_INPUT_EXPIRED
struct k_work_delayable rx_refresh_timeout_work;
#endif
#endif
};
#if defined(CONFIG_PM) && defined(CONFIG_UART_INTERRUPT_DRIVEN)
static void uart_npcx_pm_policy_state_lock_get(struct uart_npcx_data *data,
enum uart_pm_policy_state_flag flag)
{
if (atomic_test_and_set_bit(data->pm_policy_state_flag, flag) == 0) {
pm_policy_state_lock_get(PM_STATE_SUSPEND_TO_IDLE, PM_ALL_SUBSTATES);
}
}
static void uart_npcx_pm_policy_state_lock_put(struct uart_npcx_data *data,
enum uart_pm_policy_state_flag flag)
{
if (atomic_test_and_clear_bit(data->pm_policy_state_flag, flag) == 1) {
pm_policy_state_lock_put(PM_STATE_SUSPEND_TO_IDLE, PM_ALL_SUBSTATES);
}
}
#endif /* defined(CONFIG_PM) && defined(CONFIG_UART_INTERRUPT_DRIVEN) */
/* UART local functions */
static int uart_set_npcx_baud_rate(struct uart_reg *const inst, int baud_rate, int src_clk)
{
/* Fix baud rate to 115200 so far */
if (baud_rate == 115200) {
if (src_clk == 15000000) {
inst->UPSR = 0x38;
inst->UBAUD = 0x01;
} else if (src_clk == 20000000) {
inst->UPSR = 0x08;
inst->UBAUD = 0x0a;
} else {
return -EINVAL;
}
} else {
return -EINVAL;
}
return 0;
}
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
static int uart_npcx_tx_fifo_ready(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
/* True if the Tx FIFO is not completely full */
return !(GET_FIELD(inst->UFTSTS, NPCX_UFTSTS_TEMPTY_LVL) == 0);
}
static int uart_npcx_rx_fifo_available(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
/* True if at least one byte is in the Rx FIFO */
return IS_BIT_SET(inst->UFRSTS, NPCX_UFRSTS_RFIFO_NEMPTY_STS);
}
static void uart_npcx_dis_all_tx_interrupts(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
/* Disable all Tx interrupts */
inst->UFTCTL &= ~(BIT(NPCX_UFTCTL_TEMPTY_LVL_EN) |
BIT(NPCX_UFTCTL_TEMPTY_EN) |
BIT(NPCX_UFTCTL_NXMIP_EN));
}
static void uart_npcx_clear_rx_fifo(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
uint8_t scratch;
/* Read all dummy bytes out from Rx FIFO */
while (uart_npcx_rx_fifo_available(dev))
scratch = inst->URBUF;
}
static int uart_npcx_fifo_fill(const struct device *dev, const uint8_t *tx_data, int size)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
uint8_t tx_bytes = 0U;
/* If Tx FIFO is still ready to send */
while ((size - tx_bytes > 0) && uart_npcx_tx_fifo_ready(dev)) {
/* Put a character into Tx FIFO */
#ifdef CONFIG_PM
struct uart_npcx_data *data = dev->data;
uart_npcx_pm_policy_state_lock_get(data, UART_PM_POLICY_STATE_TX_FLAG);
inst->UTBUF = tx_data[tx_bytes++];
inst->UFTCTL |= BIT(NPCX_UFTCTL_NXMIP_EN);
#else
inst->UTBUF = tx_data[tx_bytes++];
#endif /* CONFIG_PM */
}
return tx_bytes;
}
static int uart_npcx_fifo_read(const struct device *dev, uint8_t *rx_data, const int size)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
unsigned int rx_bytes = 0U;
/* If least one byte is in the Rx FIFO */
while ((size - rx_bytes > 0) && uart_npcx_rx_fifo_available(dev)) {
/* Receive one byte from Rx FIFO */
rx_data[rx_bytes++] = inst->URBUF;
}
return rx_bytes;
}
static void uart_npcx_irq_tx_enable(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
inst->UFTCTL |= BIT(NPCX_UFTCTL_TEMPTY_EN);
}
static void uart_npcx_irq_tx_disable(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
inst->UFTCTL &= ~(BIT(NPCX_UFTCTL_TEMPTY_EN));
}
static int uart_npcx_irq_tx_ready(const struct device *dev)
{
return uart_npcx_tx_fifo_ready(dev);
}
static int uart_npcx_irq_tx_complete(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
/* Tx FIFO is empty or last byte is sending */
return IS_BIT_SET(inst->UFTSTS, NPCX_UFTSTS_NXMIP);
}
static void uart_npcx_irq_rx_enable(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
inst->UFRCTL |= BIT(NPCX_UFRCTL_RNEMPTY_EN);
}
static void uart_npcx_irq_rx_disable(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
inst->UFRCTL &= ~(BIT(NPCX_UFRCTL_RNEMPTY_EN));
}
static int uart_npcx_irq_rx_ready(const struct device *dev)
{
return uart_npcx_rx_fifo_available(dev);
}
static void uart_npcx_irq_err_enable(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
inst->UICTRL |= BIT(NPCX_UICTRL_EEI);
}
static void uart_npcx_irq_err_disable(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
inst->UICTRL &= ~(BIT(NPCX_UICTRL_EEI));
}
static int uart_npcx_irq_is_pending(const struct device *dev)
{
return (uart_npcx_irq_tx_ready(dev) || uart_npcx_irq_rx_ready(dev));
}
static int uart_npcx_irq_update(const struct device *dev)
{
ARG_UNUSED(dev);
return 1;
}
static void uart_npcx_irq_callback_set(const struct device *dev, uart_irq_callback_user_data_t cb,
void *cb_data)
{
struct uart_npcx_data *data = dev->data;
data->user_cb = cb;
data->user_data = cb_data;
}
static void uart_npcx_isr(const struct device *dev)
{
struct uart_npcx_data *data = dev->data;
/*
* Set pm constraint to prevent the system enter suspend state within
* the CONFIG_UART_CONSOLE_INPUT_EXPIRED_TIMEOUT period.
*/
#ifdef CONFIG_UART_CONSOLE_INPUT_EXPIRED
if (uart_npcx_irq_rx_ready(dev)) {
k_timeout_t delay = K_MSEC(CONFIG_UART_CONSOLE_INPUT_EXPIRED_TIMEOUT);
uart_npcx_pm_policy_state_lock_get(data, UART_PM_POLICY_STATE_RX_FLAG);
k_work_reschedule(&data->rx_refresh_timeout_work, delay);
}
#endif
if (data->user_cb) {
data->user_cb(dev, data->user_data);
}
#ifdef CONFIG_PM
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
if (IS_BIT_SET(inst->UFTCTL, NPCX_UFTCTL_NXMIP_EN) &&
IS_BIT_SET(inst->UFTSTS, NPCX_UFTSTS_NXMIP)) {
uart_npcx_pm_policy_state_lock_put(data, UART_PM_POLICY_STATE_TX_FLAG);
inst->UFTCTL &= ~BIT(NPCX_UFTCTL_NXMIP_EN);
}
#endif /* CONFIG_PM */
}
/*
* Poll-in implementation for interrupt driven config, forward call to
* uart_npcx_fifo_read().
*/
static int uart_npcx_poll_in(const struct device *dev, unsigned char *c)
{
return uart_npcx_fifo_read(dev, c, 1) ? 0 : -1;
}
/*
* Poll-out implementation for interrupt driven config, forward call to
* uart_npcx_fifo_fill().
*/
static void uart_npcx_poll_out(const struct device *dev, unsigned char c)
{
while (!uart_npcx_fifo_fill(dev, &c, 1))
continue;
}
#else /* !CONFIG_UART_INTERRUPT_DRIVEN */
/*
* Poll-in implementation for byte mode config, read byte from URBUF if
* available.
*/
static int uart_npcx_poll_in(const struct device *dev, unsigned char *c)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
/* Rx single byte buffer is not full */
if (!IS_BIT_SET(inst->UICTRL, NPCX_UICTRL_RBF))
return -1;
*c = inst->URBUF;
return 0;
}
/*
* Poll-out implementation for byte mode config, write byte to UTBUF if empty.
*/
static void uart_npcx_poll_out(const struct device *dev, unsigned char c)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
/* Wait while Tx single byte buffer is ready to send */
while (!IS_BIT_SET(inst->UICTRL, NPCX_UICTRL_TBE))
continue;
inst->UTBUF = c;
}
#endif /* !CONFIG_UART_INTERRUPT_DRIVEN */
/* UART api functions */
static int uart_npcx_err_check(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_reg *const inst = config->inst;
uint32_t err = 0U;
uint8_t stat = inst->USTAT;
if (IS_BIT_SET(stat, NPCX_USTAT_DOE))
err |= UART_ERROR_OVERRUN;
if (IS_BIT_SET(stat, NPCX_USTAT_PE))
err |= UART_ERROR_PARITY;
if (IS_BIT_SET(stat, NPCX_USTAT_FE))
err |= UART_ERROR_FRAMING;
return err;
}
static __unused void uart_npcx_rx_wk_isr(const struct device *dev, struct npcx_wui *wui)
{
/*
* Set pm constraint to prevent the system enter suspend state within
* the CONFIG_UART_CONSOLE_INPUT_EXPIRED_TIMEOUT period.
*/
#ifdef CONFIG_UART_CONSOLE_INPUT_EXPIRED
struct uart_npcx_data *data = dev->data;
k_timeout_t delay = K_MSEC(CONFIG_UART_CONSOLE_INPUT_EXPIRED_TIMEOUT);
uart_npcx_pm_policy_state_lock_get(data, UART_PM_POLICY_STATE_RX_FLAG);
k_work_reschedule(&data->rx_refresh_timeout_work, delay);
#endif
/*
* Disable MIWU CR_SIN interrupt to avoid the other redundant interrupts
* after ec wakes up.
*/
npcx_uart_disable_access_interrupt();
}
#ifdef CONFIG_UART_CONSOLE_INPUT_EXPIRED
static void uart_npcx_rx_refresh_timeout(struct k_work *work)
{
struct uart_npcx_data *data =
CONTAINER_OF(work, struct uart_npcx_data, rx_refresh_timeout_work);
uart_npcx_pm_policy_state_lock_put(data, UART_PM_POLICY_STATE_RX_FLAG);
}
#endif
/* UART driver registration */
static const struct uart_driver_api uart_npcx_driver_api = {
.poll_in = uart_npcx_poll_in,
.poll_out = uart_npcx_poll_out,
.err_check = uart_npcx_err_check,
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
.fifo_fill = uart_npcx_fifo_fill,
.fifo_read = uart_npcx_fifo_read,
.irq_tx_enable = uart_npcx_irq_tx_enable,
.irq_tx_disable = uart_npcx_irq_tx_disable,
.irq_tx_ready = uart_npcx_irq_tx_ready,
.irq_tx_complete = uart_npcx_irq_tx_complete,
.irq_rx_enable = uart_npcx_irq_rx_enable,
.irq_rx_disable = uart_npcx_irq_rx_disable,
.irq_rx_ready = uart_npcx_irq_rx_ready,
.irq_err_enable = uart_npcx_irq_err_enable,
.irq_err_disable = uart_npcx_irq_err_disable,
.irq_is_pending = uart_npcx_irq_is_pending,
.irq_update = uart_npcx_irq_update,
.irq_callback_set = uart_npcx_irq_callback_set,
#endif /* CONFIG_UART_INTERRUPT_DRIVEN */
};
static int uart_npcx_init(const struct device *dev)
{
const struct uart_npcx_config *const config = dev->config;
struct uart_npcx_data *const data = dev->data;
const struct device *const clk_dev = DEVICE_DT_GET(NPCX_CLK_CTRL_NODE);
struct uart_reg *const inst = config->inst;
uint32_t uart_rate;
int ret;
/* Turn on device clock first and get source clock freq. */
ret = clock_control_on(clk_dev, (clock_control_subsys_t *)&config->clk_cfg);
if (ret < 0) {
LOG_ERR("Turn on UART clock fail %d", ret);
return ret;
}
/*
* If apb2's clock is not 15MHz, we need to find the other optimized
* values of UPSR and UBAUD for baud rate 115200.
*/
ret = clock_control_get_rate(clk_dev, (clock_control_subsys_t *)&config->clk_cfg,
&uart_rate);
if (ret < 0) {
LOG_ERR("Get UART clock rate error %d", ret);
return ret;
}
/* Configure baud rate */
ret = uart_set_npcx_baud_rate(inst, data->baud_rate, uart_rate);
if (ret < 0) {
LOG_ERR("Set baud rate %d with unsupported apb clock %d failed", data->baud_rate,
uart_rate);
return ret;
}
/*
* 8-N-1, FIFO enabled. Must be done after setting
* the divisor for the new divisor to take effect.
*/
inst->UFRS = 0x00;
/* Initialize UART FIFO if mode is interrupt driven */
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
/* Enable the UART FIFO mode */
inst->UMDSL |= BIT(NPCX_UMDSL_FIFO_MD);
/* Disable all UART tx FIFO interrupts */
uart_npcx_dis_all_tx_interrupts(dev);
/* Clear UART rx FIFO */
uart_npcx_clear_rx_fifo(dev);
/* Configure UART interrupts */
config->irq_config_func(dev);
#endif
if (IS_ENABLED(CONFIG_PM)) {
/* Initialize a miwu device input and its callback function */
npcx_miwu_init_dev_callback(&data->uart_rx_cb, &config->uart_rx_wui,
uart_npcx_rx_wk_isr, dev);
npcx_miwu_manage_dev_callback(&data->uart_rx_cb, true);
/*
* Configure the UART wake-up event triggered from a falling
* edge on CR_SIN pin. No need for callback function.
*/
npcx_miwu_interrupt_configure(&config->uart_rx_wui, NPCX_MIWU_MODE_EDGE,
NPCX_MIWU_TRIG_LOW);
#ifdef CONFIG_UART_CONSOLE_INPUT_EXPIRED
k_work_init_delayable(&data->rx_refresh_timeout_work, uart_npcx_rx_refresh_timeout);
#endif
}
/* Configure pin-mux for uart device */
ret = pinctrl_apply_state(config->pcfg, PINCTRL_STATE_DEFAULT);
if (ret < 0) {
LOG_ERR("UART pinctrl setup failed (%d)", ret);
return ret;
}
return 0;
}
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
#define NPCX_UART_IRQ_CONFIG_FUNC_DECL(inst) \
static void uart_npcx_irq_config_##inst(const struct device *dev)
#define NPCX_UART_IRQ_CONFIG_FUNC_INIT(inst) .irq_config_func = uart_npcx_irq_config_##inst,
#define NPCX_UART_IRQ_CONFIG_FUNC(inst) \
static void uart_npcx_irq_config_##inst(const struct device *dev) \
{ \
IRQ_CONNECT(DT_INST_IRQN(inst), DT_INST_IRQ(inst, priority), uart_npcx_isr, \
DEVICE_DT_INST_GET(inst), 0); \
irq_enable(DT_INST_IRQN(inst)); \
}
#else
#define NPCX_UART_IRQ_CONFIG_FUNC_DECL(inst)
#define NPCX_UART_IRQ_CONFIG_FUNC_INIT(inst)
#define NPCX_UART_IRQ_CONFIG_FUNC(inst)
#endif
#define NPCX_UART_INIT(i) \
NPCX_UART_IRQ_CONFIG_FUNC_DECL(i); \
\
PINCTRL_DT_INST_DEFINE(i); \
\
static const struct uart_npcx_config uart_npcx_cfg_##i = { \
.inst = (struct uart_reg *)DT_INST_REG_ADDR(i), \
.clk_cfg = NPCX_DT_CLK_CFG_ITEM(i), \
.uart_rx_wui = NPCX_DT_WUI_ITEM_BY_NAME(0, uart_rx), \
.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(i), \
NPCX_UART_IRQ_CONFIG_FUNC_INIT(i) \
}; \
\
static struct uart_npcx_data uart_npcx_data_##i = { .baud_rate = DT_INST_PROP( \
i, current_speed) }; \
\
DEVICE_DT_INST_DEFINE(i, &uart_npcx_init, NULL, &uart_npcx_data_##i, \
&uart_npcx_cfg_##i, PRE_KERNEL_1, CONFIG_SERIAL_INIT_PRIORITY, \
&uart_npcx_driver_api); \
\
NPCX_UART_IRQ_CONFIG_FUNC(i)
DT_INST_FOREACH_STATUS_OKAY(NPCX_UART_INIT)
#define ENABLE_MIWU_CRIN_IRQ(i) \
npcx_miwu_irq_get_and_clear_pending(&uart_npcx_cfg_##i.uart_rx_wui); \
npcx_miwu_irq_enable(&uart_npcx_cfg_##i.uart_rx_wui);
#define DISABLE_MIWU_CRIN_IRQ(i) npcx_miwu_irq_disable(&uart_npcx_cfg_##i.uart_rx_wui);
void npcx_uart_enable_access_interrupt(void)
{
DT_INST_FOREACH_STATUS_OKAY(ENABLE_MIWU_CRIN_IRQ)
}
void npcx_uart_disable_access_interrupt(void)
{
DT_INST_FOREACH_STATUS_OKAY(DISABLE_MIWU_CRIN_IRQ)
}