blob: 2573434f34f7fcd9b272796e7f5ba598db5c6023 [file] [log] [blame]
/*
* Copyright (c) 2021 Telink Semiconductor
*
* SPDX-License-Identifier: Apache-2.0
*/
#include "analog.h"
#include "clock.h"
#include <zephyr/device.h>
#include <zephyr/drivers/uart.h>
#include <zephyr/drivers/pinctrl.h>
#include <zephyr/irq.h>
/* Driver dts compatibility: telink,b91_uart */
#define DT_DRV_COMPAT telink_b91_uart
/* Get UART instance */
#define GET_UART(dev) ((volatile struct uart_b91_t *) \
((const struct uart_b91_config *)dev->config)->uart_addr)
/* UART TX buffer count max value */
#define UART_TX_BUF_CNT ((uint8_t)8u)
/* UART TX/RX data registers size */
#define UART_DATA_SIZE ((uint8_t)4u)
/* Parity type */
#define UART_PARITY_NONE ((uint8_t)0u)
#define UART_PARITY_EVEN ((uint8_t)1u)
#define UART_PARITY_ODD ((uint8_t)2u)
/* Stop bits length */
#define UART_STOP_BIT_1 ((uint8_t)0u)
#define UART_STOP_BIT_1P5 BIT(4)
#define UART_STOP_BIT_2 BIT(5)
/* TX RX reset bits */
#define UART_RX_RESET_BIT BIT(6)
#define UART_TX_RESET_BIT BIT(7)
/* B91 UART registers structure */
struct uart_b91_t {
uint8_t data_buf[UART_DATA_SIZE];
uint16_t clk_div;
uint8_t ctrl0;
uint8_t ctrl1;
uint8_t ctrl2;
uint8_t ctrl3;
uint16_t rxtimeout;
uint8_t bufcnt;
uint8_t status;
uint8_t txrx_status;
uint8_t state;
};
/* B91 UART data structure */
struct uart_b91_data {
uint8_t tx_byte_index;
uint8_t rx_byte_index;
struct uart_config cfg;
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
uart_irq_callback_user_data_t callback;
void *cb_data;
#endif
};
/* B91 UART config structure */
struct uart_b91_config {
const struct pinctrl_dev_config *pcfg;
uint32_t uart_addr;
uint32_t baud_rate;
void (*pirq_connect)(void);
};
/* rxtimeout register enums */
enum {
UART_ERR_IRQ_MASK = BIT(15),
};
/* ctrl0 register enums */
enum {
UART_RX_IRQ_MASK = BIT(6),
UART_TX_IRQ_MASK = BIT(7),
};
/* ctrl3 register enums */
enum {
FLD_UART_RX_IRQ_TRIQ_LEV_OFFSET = 0,
FLD_UART_TX_IRQ_TRIQ_LEV_OFFSET = 4,
};
/* bufcnt register enums */
enum {
FLD_UART_RX_BUF_CNT_OFFSET = 0,
FLD_UART_TX_BUF_CNT_OFFSET = 4,
};
/* status register enums */
enum {
UART_IRQ_STATUS = BIT(3),
UART_RX_ERR_STATUS = BIT(7),
};
/* Get tx fifo count */
static inline uint8_t uart_b91_get_tx_bufcnt(volatile struct uart_b91_t *uart)
{
return (uart->bufcnt & FLD_UART_TX_BUF_CNT) >> FLD_UART_TX_BUF_CNT_OFFSET;
}
/* Get rx fifo count */
static inline uint8_t uart_b91_get_rx_bufcnt(volatile struct uart_b91_t *uart)
{
return (uart->bufcnt & FLD_UART_RX_BUF_CNT) >> FLD_UART_RX_BUF_CNT_OFFSET;
}
/* Check for prime */
static uint8_t uart_b91_is_prime(uint32_t n)
{
uint32_t i = 5;
if (n <= 3) {
return 1;
} else if ((n % 2 == 0) || (n % 3 == 0)) {
return 0;
}
for (i = 5; i * i < n; i += 6) {
if ((n % i == 0) || (n % (i + 2)) == 0) {
return 0;
}
}
return 1;
}
/* Calculate the best bit width */
static void uart_b91_cal_div_and_bwpc(uint32_t baudrate, uint32_t pclk,
uint16_t *divider, uint8_t *bwpc)
{
uint8_t i = 0, j = 0;
uint32_t primeInt = 0;
uint8_t primeDec = 0;
uint32_t D_intdec[13], D_int[13];
uint8_t D_dec[13];
primeInt = pclk / baudrate;
primeDec = 10 * pclk / baudrate - 10 * primeInt;
if (uart_b91_is_prime(primeInt)) {
primeInt += 1;
} else if (primeDec > 5) {
primeInt += 1;
if (uart_b91_is_prime(primeInt)) {
primeInt -= 1;
}
}
for (i = 3; i <= 15; i++) {
D_intdec[i - 3] = (10 * primeInt) / (i + 1);
D_dec[i - 3] = D_intdec[i - 3] - 10 * (D_intdec[i - 3] / 10);
D_int[i - 3] = D_intdec[i - 3] / 10;
}
/* find the max and min one decimation point */
uint8_t position_min = 0, position_max = 0;
uint32_t min = 0xffffffff, max = 0x00;
for (j = 0; j < 13; j++) {
if ((D_dec[j] <= min) && (D_int[j] != 0x01)) {
min = D_dec[j];
position_min = j;
}
if (D_dec[j] >= max) {
max = D_dec[j];
position_max = j;
}
}
if ((D_dec[position_min] < 5) && (D_dec[position_max] >= 5)) {
if (D_dec[position_min] < (10 - D_dec[position_max])) {
*bwpc = position_min + 3;
*divider = D_int[position_min] - 1;
} else {
*bwpc = position_max + 3;
*divider = D_int[position_max];
}
} else if ((D_dec[position_min] < 5) && (D_dec[position_max] < 5)) {
*bwpc = position_min + 3;
*divider = D_int[position_min] - 1;
} else {
*bwpc = position_max + 3;
*divider = D_int[position_max];
}
}
/* Initializes the UART instance */
static void uart_b91_init(volatile struct uart_b91_t *uart, uint16_t divider,
uint8_t bwpc, uint8_t parity, uint8_t stop_bit)
{
/* config clock */
divider = divider | FLD_UART_CLK_DIV_EN;
uart->ctrl0 = bwpc;
uart->clk_div = divider;
/* config parity */
if (parity) {
/* enable parity function */
uart->ctrl1 |= FLD_UART_PARITY_ENABLE;
if (parity == UART_PARITY_EVEN) {
/* enable even parity */
uart->ctrl1 &= (~FLD_UART_PARITY_POLARITY);
} else if (parity == UART_PARITY_ODD) {
/* enable odd parity */
uart->ctrl1 |= FLD_UART_PARITY_POLARITY;
}
} else {
uart->ctrl1 &= (~FLD_UART_PARITY_ENABLE); /* disable parity function */
}
/* stop bit config */
uart->ctrl1 &= (~FLD_UART_STOP_SEL);
uart->ctrl1 |= stop_bit;
}
/* API implementation: irq handler */
static void uart_b91_irq_handler(const struct device *dev)
{
#ifndef CONFIG_UART_INTERRUPT_DRIVEN
ARG_UNUSED(dev);
#else
struct uart_b91_data *data = dev->data;
if (data->callback != NULL) {
data->callback(dev, data->cb_data);
}
#endif
}
/* API implementation: configure */
static int uart_b91_configure(const struct device *dev,
const struct uart_config *cfg)
{
struct uart_b91_data *data = dev->data;
uint16_t divider;
uint8_t bwpc;
uint8_t parity;
uint8_t stop_bits;
volatile struct uart_b91_t *uart = GET_UART(dev);
/* check parity */
if (cfg->parity == UART_CFG_PARITY_NONE) {
parity = UART_PARITY_NONE;
} else if (cfg->parity == UART_CFG_PARITY_ODD) {
parity = UART_PARITY_ODD;
} else if (cfg->parity == UART_CFG_PARITY_EVEN) {
parity = UART_PARITY_EVEN;
} else {
return -ENOTSUP;
}
/* check stop bits */
if (cfg->stop_bits == UART_CFG_STOP_BITS_1) {
stop_bits = UART_STOP_BIT_1;
} else if (cfg->stop_bits == UART_CFG_STOP_BITS_1_5) {
stop_bits = UART_STOP_BIT_1P5;
} else if (cfg->stop_bits == UART_CFG_STOP_BITS_2) {
stop_bits = UART_STOP_BIT_2;
} else {
return -ENOTSUP;
}
/* check flow control */
if (cfg->flow_ctrl != UART_CFG_FLOW_CTRL_NONE) {
return -ENOTSUP;
}
/* UART configure */
uart_b91_cal_div_and_bwpc(cfg->baudrate, sys_clk.pclk * 1000 * 1000, &divider, &bwpc);
uart_b91_init(uart, divider, bwpc, parity, stop_bits);
/* save configuration */
data->cfg = *cfg;
return 0;
}
/* API implementation: config_get */
static int uart_b91_config_get(const struct device *dev,
struct uart_config *cfg)
{
struct uart_b91_data *data = dev->data;
*cfg = data->cfg;
return 0;
}
/* API implementation: driver initialization */
static int uart_b91_driver_init(const struct device *dev)
{
int status = 0;
uint16_t divider = 0u;
uint8_t bwpc = 0u;
volatile struct uart_b91_t *uart = GET_UART(dev);
const struct uart_b91_config *cfg = dev->config;
struct uart_b91_data *data = dev->data;
/* Reset Tx, Rx status before usage */
uart->status |= UART_RX_RESET_BIT | UART_TX_RESET_BIT;
data->rx_byte_index = 0;
data->tx_byte_index = 0;
/* configure pins */
status = pinctrl_apply_state(cfg->pcfg, PINCTRL_STATE_DEFAULT);
if (status < 0) {
return status;
}
uart_b91_cal_div_and_bwpc(cfg->baud_rate, sys_clk.pclk * 1000 * 1000, &divider, &bwpc);
uart_b91_init(uart, divider, bwpc, UART_PARITY_NONE, UART_STOP_BIT_1);
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
cfg->pirq_connect();
#endif
return 0;
}
/* API implementation: poll_out */
static void uart_b91_poll_out(const struct device *dev, uint8_t c)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
struct uart_b91_data *data = dev->data;
while (uart_b91_get_tx_bufcnt(uart) >= UART_TX_BUF_CNT) {
};
uart->data_buf[data->tx_byte_index] = c;
data->tx_byte_index = (data->tx_byte_index + 1) % ARRAY_SIZE(uart->data_buf);
}
/* API implementation: poll_in */
static int uart_b91_poll_in(const struct device *dev, unsigned char *c)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
struct uart_b91_data *data = dev->data;
if (uart_b91_get_rx_bufcnt(uart) == 0) {
return -1;
}
*c = uart->data_buf[data->rx_byte_index];
data->rx_byte_index = (data->rx_byte_index + 1) % ARRAY_SIZE(uart->data_buf);
return 0;
}
/* API implementation: err_check */
static int uart_b91_err_check(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
return ((uart->status & UART_RX_ERR_STATUS) != 0) ? 1 : 0;
}
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
/* API implementation: fifo_fill */
static int uart_b91_fifo_fill(const struct device *dev,
const uint8_t *tx_data,
int size)
{
int i = 0;
volatile struct uart_b91_t *uart = GET_UART(dev);
if (size > UART_DATA_SIZE) {
size = UART_DATA_SIZE;
}
for (i = 0; i < size; i++) {
if (uart_b91_get_rx_bufcnt(uart) != 0) {
break;
}
uart_b91_poll_out(dev, tx_data[i]);
}
return i;
}
/* API implementation: fifo_read */
static int uart_b91_fifo_read(const struct device *dev,
uint8_t *rx_data,
const int size)
{
int rx_count;
volatile struct uart_b91_t *uart = GET_UART(dev);
for (rx_count = 0; rx_count < size; rx_count++) {
if (uart_b91_get_rx_bufcnt(uart) == 0) {
break;
}
uart_b91_poll_in(dev, &rx_data[rx_count]);
}
return rx_count;
}
/* API implementation: irq_tx_enable */
static void uart_b91_irq_tx_enable(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
uart->ctrl3 = (uart->ctrl3 & (~FLD_UART_TX_IRQ_TRIQ_LEV)) |
BIT(FLD_UART_TX_IRQ_TRIQ_LEV_OFFSET);
uart->ctrl0 |= UART_TX_IRQ_MASK;
}
/* API implementation: irq_tx_disable */
static void uart_b91_irq_tx_disable(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
uart->ctrl0 &= ~UART_TX_IRQ_MASK;
}
/* API implementation: irq_tx_ready */
static int uart_b91_irq_tx_ready(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
return ((uart_b91_get_tx_bufcnt(uart) < UART_TX_BUF_CNT) &&
((uart->ctrl0 & UART_TX_IRQ_MASK) != 0)) ? 1 : 0;
}
/* API implementation: irq_tx_complete */
static int uart_b91_irq_tx_complete(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
return (uart_b91_get_tx_bufcnt(uart) == 0) ? 1 : 0;
}
/* API implementation: irq_rx_enable */
static void uart_b91_irq_rx_enable(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
uart->ctrl3 = (uart->ctrl3 & (~FLD_UART_RX_IRQ_TRIQ_LEV)) |
BIT(FLD_UART_RX_IRQ_TRIQ_LEV_OFFSET);
uart->ctrl0 |= UART_RX_IRQ_MASK;
}
/* API implementation: irq_rx_disable */
static void uart_b91_irq_rx_disable(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
uart->ctrl0 &= ~UART_RX_IRQ_MASK;
}
/* API implementation: irq_rx_ready */
static int uart_b91_irq_rx_ready(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
return (uart_b91_get_rx_bufcnt(uart) > 0) ? 1 : 0;
}
/* API implementation: irq_err_enable */
static void uart_b91_irq_err_enable(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
uart->rxtimeout |= UART_ERR_IRQ_MASK;
}
/* API implementation: irq_err_disable*/
static void uart_b91_irq_err_disable(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
uart->rxtimeout &= ~UART_ERR_IRQ_MASK;
}
/* API implementation: irq_is_pending */
static int uart_b91_irq_is_pending(const struct device *dev)
{
volatile struct uart_b91_t *uart = GET_UART(dev);
return ((uart->status & UART_IRQ_STATUS) != 0) ? 1 : 0;
}
/* API implementation: irq_update */
static int uart_b91_irq_update(const struct device *dev)
{
ARG_UNUSED(dev);
/* nothing to be done */
return 1;
}
/* API implementation: irq_callback_set */
static void uart_b91_irq_callback_set(const struct device *dev,
uart_irq_callback_user_data_t cb,
void *cb_data)
{
struct uart_b91_data *data = dev->data;
data->callback = cb;
data->cb_data = cb_data;
}
#endif /* CONFIG_UART_INTERRUPT_DRIVEN */
static const struct uart_driver_api uart_b91_driver_api = {
.poll_in = uart_b91_poll_in,
.poll_out = uart_b91_poll_out,
.err_check = uart_b91_err_check,
.configure = uart_b91_configure,
.config_get = uart_b91_config_get,
#ifdef CONFIG_UART_INTERRUPT_DRIVEN
.fifo_fill = uart_b91_fifo_fill,
.fifo_read = uart_b91_fifo_read,
.irq_tx_enable = uart_b91_irq_tx_enable,
.irq_tx_disable = uart_b91_irq_tx_disable,
.irq_tx_ready = uart_b91_irq_tx_ready,
.irq_tx_complete = uart_b91_irq_tx_complete,
.irq_rx_enable = uart_b91_irq_rx_enable,
.irq_rx_disable = uart_b91_irq_rx_disable,
.irq_rx_ready = uart_b91_irq_rx_ready,
.irq_err_enable = uart_b91_irq_err_enable,
.irq_err_disable = uart_b91_irq_err_disable,
.irq_is_pending = uart_b91_irq_is_pending,
.irq_update = uart_b91_irq_update,
.irq_callback_set = uart_b91_irq_callback_set,
#endif
};
#define UART_B91_INIT(n) \
\
static void uart_b91_irq_connect_##n(void); \
\
PINCTRL_DT_INST_DEFINE(n); \
\
static const struct uart_b91_config uart_b91_cfg_##n = \
{ \
.uart_addr = DT_INST_REG_ADDR(n), \
.baud_rate = DT_INST_PROP(n, current_speed), \
.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(n), \
.pirq_connect = uart_b91_irq_connect_##n \
}; \
\
static struct uart_b91_data uart_b91_data_##n; \
\
DEVICE_DT_INST_DEFINE(n, uart_b91_driver_init, \
NULL, \
&uart_b91_data_##n, \
&uart_b91_cfg_##n, \
PRE_KERNEL_1, \
CONFIG_SERIAL_INIT_PRIORITY, \
(void *)&uart_b91_driver_api); \
\
static void uart_b91_irq_connect_##n(void) \
{ \
IRQ_CONNECT(DT_INST_IRQN(n), DT_INST_IRQ(n, priority), \
uart_b91_irq_handler, \
DEVICE_DT_INST_GET(n), 0); \
\
riscv_plic_irq_enable(DT_INST_IRQN(n)); \
riscv_plic_set_priority(DT_INST_IRQN(n), DT_INST_IRQ(n, priority)); \
}
DT_INST_FOREACH_STATUS_OKAY(UART_B91_INIT)