zephyr/drivers/serial/uart_ra.c

396 lines
11 KiB
C

/*
* Copyright (c) 2023 TOKITA Hiroshi <tokita.hiroshi@fujitsu.com>
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT renesas_ra_uart_sci
#include <zephyr/drivers/uart.h>
#include <zephyr/drivers/clock_control.h>
#include <zephyr/drivers/pinctrl.h>
#include <zephyr/spinlock.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(ra_uart_sci, CONFIG_UART_LOG_LEVEL);
struct uart_ra_cfg {
mem_addr_t regs;
const struct device *clock_dev;
clock_control_subsys_t clock_id;
const struct pinctrl_dev_config *pcfg;
};
struct uart_ra_data {
struct uart_config current_config;
uint32_t clk_rate;
struct k_spinlock lock;
};
#define REG_MASK(reg) (BIT_MASK(_CONCAT(reg, _LEN)) << _CONCAT(reg, _POS))
/* Registers */
#define SMR 0x00 /*!< Serial Mode Register */
#define BRR 0x01 /*!< Bit Rate Register */
#define SCR 0x02 /*!< Serial Control Register */
#define TDR 0x03 /*!< Transmit Data Register */
#define SSR 0x04 /*!< Serial Status Register */
#define RDR 0x05 /*!< Receive Data Register */
#define SEMR 0x07 /*!< Serial Extended Mode Register */
#define MDDR 0x12 /*!< Modulation Duty Register */
#define LSR 0x18 /*!< Line Status Register */
/*
* SMR (Serial Mode Register)
*
* - CKS[0..2]: Clock Select
* - MP[2..3]: Multi-Processor Mode(Valid only in asynchronous mode)
* - STOP[3..4]: Stop Bit Length(Valid only in asynchronous mode)
* - PM[4..5]: Parity Mode (Valid only when the PE bit is 1)
* - PE[5..6]: Parity Enable(Valid only in asynchronous mode)
* - CHR[6..7]: Character Length(Valid only in asynchronous mode)
* - CM[7..8]: Communication Mode
*/
#define SMR_CKS_POS (0)
#define SMR_CKS_LEN (2)
#define SMR_MP_POS (2)
#define SMR_MP_LEN (1)
#define SMR_STOP_POS (3)
#define SMR_STOP_LEN (1)
#define SMR_PM_POS (4)
#define SMR_PM_LEN (1)
#define SMR_PE_POS (5)
#define SMR_PE_LEN (1)
#define SMR_CHR_POS (6)
#define SMR_CHR_LEN (1)
#define SMR_CM_POS (7)
#define SMR_CM_LEN (1)
/**
* SCR (Serial Control Register)
*
* - CKE[0..2]: Clock Enable
* - TEIE[2..3]: Transmit End Interrupt Enable
* - MPIE[3..4]: Multi-Processor Interrupt Enable (Valid in asynchronous
* - RE[4..5]: Receive Enable
* - TE[5..6]: Transmit Enable
* - RIE[6..7]: Receive Interrupt Enable
* - TIE[7..8]: Transmit Interrupt Enable
*/
#define SCR_CKE_POS (0)
#define SCR_CKE_LEN (2)
#define SCR_TEIE_POS (2)
#define SCR_TEIE_LEN (1)
#define SCR_MPIE_POS (3)
#define SCR_MPIE_LEN (1)
#define SCR_RE_POS (4)
#define SCR_RE_LEN (1)
#define SCR_TE_POS (5)
#define SCR_TE_LEN (1)
#define SCR_RIE_POS (6)
#define SCR_RIE_LEN (1)
#define SCR_TIE_POS (7)
#define SCR_TIE_LEN (1)
/**
* SSR (Serial Status Register)
*
* - MPBT[0..1]: Multi-Processor Bit Transfer
* - MPB[1..2]: Multi-Processor
* - TEND[2..3]: Transmit End Flag
* - PER[3..4]: Parity Error Flag
* - FER[4..5]: Framing Error Flag
* - ORER[5..6]: Overrun Error Flag
* - RDRF[6..7]: Receive Data Full Flag
* - TDRE[7..8]: Transmit Data Empty Flag
*/
#define SSR_MPBT_POS (0)
#define SSR_MPBT_LEN (1)
#define SSR_MPB_POS (1)
#define SSR_MPB_LEN (1)
#define SSR_TEND_POS (2)
#define SSR_TEND_LEN (1)
#define SSR_PER_POS (3)
#define SSR_PER_LEN (1)
#define SSR_FER_POS (4)
#define SSR_FER_LEN (1)
#define SSR_ORER_POS (5)
#define SSR_ORER_LEN (1)
#define SSR_RDRF_POS (6)
#define SSR_RDRF_LEN (1)
#define SSR_TDRE_POS (7)
#define SSR_TDRE_LEN (1)
/**
* SEMR (Serial Extended Mode Register)
*
* - ACS0[0..1]: Asynchronous Mode Clock Source Select
* - PADIS[1..2]: Preamble function Disable
* - BRME[2..3]: Bit Rate Modulation Enable
* - ABCSE[3..4]: Asynchronous Mode Extended Base Clock Select
* - ABCS[4..5]: Asynchronous Mode Base Clock Select
* - NFEN[5..6]: Digital Noise Filter Function Enable
* - BGDM[6..7]: Baud Rate Generator Double-Speed Mode Select
* - RXDESEL[7..8]: Asynchronous Start Bit Edge Detection Select
*/
#define SEMR_ACS0_POS (0)
#define SEMR_ACS0_LEN (1)
#define SEMR_PADIS_POS (1)
#define SEMR_PADIS_LEN (1)
#define SEMR_BRME_POS (2)
#define SEMR_BRME_LEN (1)
#define SEMR_ABCSE_POS (3)
#define SEMR_ABCSE_LEN (1)
#define SEMR_ABCS_POS (4)
#define SEMR_ABCS_LEN (1)
#define SEMR_NFEN_POS (5)
#define SEMR_NFEN_LEN (1)
#define SEMR_BGDM_POS (6)
#define SEMR_BGDM_LEN (1)
#define SEMR_RXDESEL_POS (7)
#define SEMR_RXDESEL_LEN (1)
/**
* LSR (Line Status Register)
*
* - ORER[0..1]: Overrun Error Flag
* - FNUM[2..7]: Framing Error Count
* - PNUM[8..13]: Parity Error Count
*/
#define LSR_ORER_POS (0)
#define LSR_ORER_LEN (1)
#define LSR_FNUM_POS (2)
#define LSR_FNUM_LEN (5)
#define LSR_PNUM_POS (8)
#define LSR_PNUM_LEN (5)
static uint8_t uart_ra_read_8(const struct device *dev,
uint32_t offs)
{
const struct uart_ra_cfg *config = dev->config;
return sys_read8(config->regs + offs);
}
static void uart_ra_write_8(const struct device *dev,
uint32_t offs, uint8_t value)
{
const struct uart_ra_cfg *config = dev->config;
sys_write8(value, config->regs + offs);
}
static uint16_t uart_ra_read_16(const struct device *dev,
uint32_t offs)
{
const struct uart_ra_cfg *config = dev->config;
return sys_read16(config->regs + offs);
}
static void uart_ra_write_16(const struct device *dev,
uint32_t offs, uint16_t value)
{
const struct uart_ra_cfg *config = dev->config;
sys_write16(value, config->regs + offs);
}
static void uart_ra_set_baudrate(const struct device *dev,
uint32_t baud_rate)
{
struct uart_ra_data *data = dev->data;
uint8_t reg_val;
reg_val = uart_ra_read_8(dev, SEMR);
reg_val |= REG_MASK(SEMR_BGDM);
reg_val &= ~(REG_MASK(SEMR_BRME) | REG_MASK(SEMR_ABCSE) | REG_MASK(SEMR_ABCS));
uart_ra_write_8(dev, SEMR, reg_val);
reg_val = (data->clk_rate / (16 * data->current_config.baudrate)) - 1;
uart_ra_write_8(dev, BRR, reg_val);
}
static int uart_ra_poll_in(const struct device *dev, unsigned char *p_char)
{
struct uart_ra_data *data = dev->data;
int ret = 0;
k_spinlock_key_t key = k_spin_lock(&data->lock);
if ((uart_ra_read_8(dev, SSR) & REG_MASK(SSR_RDRF)) == 0) {
ret = -1;
goto unlock;
}
*p_char = uart_ra_read_8(dev, RDR);
unlock:
k_spin_unlock(&data->lock, key);
return ret;
}
static void uart_ra_poll_out(const struct device *dev, unsigned char out_char)
{
struct uart_ra_data *data = dev->data;
k_spinlock_key_t key = k_spin_lock(&data->lock);
uart_ra_write_8(dev, TDR, out_char);
while (!(uart_ra_read_8(dev, SSR) & REG_MASK(SSR_TEND)) ||
!(uart_ra_read_8(dev, SSR) & REG_MASK(SSR_TDRE))) {
;
}
k_spin_unlock(&data->lock, key);
}
static int uart_ra_configure(const struct device *dev,
const struct uart_config *cfg)
{
struct uart_ra_data *data = dev->data;
uint16_t reg_val;
k_spinlock_key_t key;
if (cfg->parity != UART_CFG_PARITY_NONE || cfg->stop_bits != UART_CFG_STOP_BITS_1 ||
cfg->data_bits != UART_CFG_DATA_BITS_8 || cfg->flow_ctrl != UART_CFG_FLOW_CTRL_NONE) {
return -ENOTSUP;
}
key = k_spin_lock(&data->lock);
/* Disable Transmit and Receive */
reg_val = uart_ra_read_8(dev, SCR);
reg_val &= ~(REG_MASK(SCR_TE) | REG_MASK(SCR_RE));
uart_ra_write_8(dev, SCR, reg_val);
/* Resetting Errors Registers */
reg_val = uart_ra_read_8(dev, SSR);
reg_val &= ~(REG_MASK(SSR_PER) | REG_MASK(SSR_FER) | REG_MASK(SSR_ORER) |
REG_MASK(SSR_RDRF) | REG_MASK(SSR_TDRE));
uart_ra_write_8(dev, SSR, reg_val);
reg_val = uart_ra_read_16(dev, LSR);
reg_val &= ~(REG_MASK(LSR_ORER));
uart_ra_write_16(dev, LSR, reg_val);
/* Select internal clock */
reg_val = uart_ra_read_8(dev, SCR);
reg_val &= ~(REG_MASK(SCR_CKE));
uart_ra_write_8(dev, SCR, reg_val);
/* Serial Configuration (8N1) & Clock divider selection */
reg_val = uart_ra_read_8(dev, SMR);
reg_val &= ~(REG_MASK(SMR_CM) | REG_MASK(SMR_CHR) | REG_MASK(SMR_PE) | REG_MASK(SMR_PM) |
REG_MASK(SMR_STOP) | REG_MASK(SMR_CKS));
uart_ra_write_8(dev, SMR, reg_val);
/* Set baudrate */
uart_ra_set_baudrate(dev, cfg->baudrate);
/* Enable Transmit & Receive + disable Interrupts */
reg_val = uart_ra_read_8(dev, SCR);
reg_val |= (REG_MASK(SCR_TE) | REG_MASK(SCR_RE));
reg_val &=
~(REG_MASK(SCR_TIE) | REG_MASK(SCR_RIE) | REG_MASK(SCR_MPIE) | REG_MASK(SCR_TEIE));
uart_ra_write_8(dev, SCR, reg_val);
data->current_config = *cfg;
k_spin_unlock(&data->lock, key);
return 0;
}
#ifdef CONFIG_UART_USE_RUNTIME_CONFIGURE
static int uart_ra_config_get(const struct device *dev,
struct uart_config *cfg)
{
struct uart_ra_data *data = dev->data;
*cfg = data->current_config;
return 0;
}
#endif /* CONFIG_UART_USE_RUNTIME_CONFIGURE */
static int uart_ra_init(const struct device *dev)
{
const struct uart_ra_cfg *config = dev->config;
struct uart_ra_data *data = dev->data;
int ret;
/* Configure dt provided device signals when available */
ret = pinctrl_apply_state(config->pcfg, PINCTRL_STATE_DEFAULT);
if (ret < 0) {
return ret;
}
if (!device_is_ready(config->clock_dev)) {
return -ENODEV;
}
ret = clock_control_on(config->clock_dev, config->clock_id);
if (ret < 0) {
return ret;
}
ret = clock_control_get_rate(config->clock_dev, config->clock_id, &data->clk_rate);
if (ret < 0) {
return ret;
}
DEVICE_MMIO_MAP(dev, K_MEM_CACHE_NONE);
ret = uart_ra_configure(dev, &data->current_config);
if (ret != 0) {
return ret;
}
return 0;
}
static const struct uart_driver_api uart_ra_driver_api = {
.poll_in = uart_ra_poll_in,
.poll_out = uart_ra_poll_out,
#ifdef CONFIG_UART_USE_RUNTIME_CONFIGURE
.configure = uart_ra_configure,
.config_get = uart_ra_config_get,
#endif
};
/* Device Instantiation */
#define UART_RCAR_INIT_CFG(n) \
PINCTRL_DT_DEFINE(DT_INST_PARENT(n)); \
static const struct uart_ra_cfg uart_ra_cfg_##n = { \
.regs = DT_REG_ADDR(DT_INST_PARENT(n)), \
.clock_dev = DEVICE_DT_GET(DT_CLOCKS_CTLR(DT_INST_PARENT(n))), \
.clock_id = \
(clock_control_subsys_t)DT_CLOCKS_CELL_BY_IDX(DT_INST_PARENT(n), 0, id), \
.pcfg = PINCTRL_DT_DEV_CONFIG_GET(DT_INST_PARENT(n)), \
}
#define UART_RCAR_INIT(n) \
UART_RCAR_INIT_CFG(n); \
\
static struct uart_ra_data uart_ra_data_##n = { \
.current_config = { \
.baudrate = DT_INST_PROP(n, current_speed), \
.parity = UART_CFG_PARITY_NONE, \
.stop_bits = UART_CFG_STOP_BITS_1, \
.data_bits = UART_CFG_DATA_BITS_8, \
.flow_ctrl = UART_CFG_FLOW_CTRL_NONE, \
}, \
}; \
\
DEVICE_DT_INST_DEFINE(n, \
uart_ra_init, \
NULL, \
&uart_ra_data_##n, \
&uart_ra_cfg_##n, \
PRE_KERNEL_1, CONFIG_SERIAL_INIT_PRIORITY, \
&uart_ra_driver_api); \
\
DT_INST_FOREACH_STATUS_OKAY(UART_RCAR_INIT)