zephyr/drivers/serial/uart_sy1xx.c

320 lines
8.1 KiB
C

/*
* SPDX-License-Identifier: Apache-2.0
* Copyright (c) 2024 sensry.io
*/
#define DT_DRV_COMPAT sensry_sy1xx_uart
#include <zephyr/device.h>
#include <zephyr/drivers/uart.h>
#include <soc.h>
#include <zephyr/sys/printk.h>
#include <udma.h>
#include <pad_ctrl.h>
struct sy1xx_uart_config {
uint32_t base;
uint32_t inst;
};
typedef struct {
uint16_t data_len;
uint8_t *data;
} uartTransfer_t;
typedef enum {
DRIVERS_UART_STOP_1,
DRIVERS_UART_STOP_1_5,
DRIVERS_UART_STOP_2
} uart_stop_t;
typedef enum {
DRIVERS_UART_PAR_NONE,
DRIVERS_UART_PAR_EVEN,
DRIVERS_UART_PAR_ODD,
DRIVERS_UART_PAR_MARK,
DRIVERS_UART_PAR_SPACE
} uart_parity_t;
typedef struct {
uint32_t baudrate;
uart_stop_t stopbits;
uart_parity_t parity;
} uartConfig_t;
#define DEVICE_MAX_BUFFER_SIZE (512)
struct sy1xx_uart_data {
uint8_t write[DEVICE_MAX_BUFFER_SIZE];
uint8_t read[DEVICE_MAX_BUFFER_SIZE];
};
/* prototypes */
static int32_t drivers_uart_read(const struct device *dev, uartTransfer_t *request);
static int32_t drivers_uart_write(const struct device *dev, uartTransfer_t *request);
static int32_t drivers_uart_configure(const struct device *dev, uartConfig_t *uart_cfg)
{
struct sy1xx_uart_config *config = (struct sy1xx_uart_config *)dev->config;
if (uart_cfg->baudrate == 0) {
return -1;
}
/*
* The counter in the UDMA will count from 0 to div included
* and then will restart from 0, so we must give div - 1 as
* divider
*/
int32_t divider = soc_get_peripheral_clock() / uart_cfg->baudrate - 1;
/*
* [31:16]: clock divider (from SoC clock)
* [9]: RX enable
* [8]: TX enable
* [3]: stop bits 0 = 1 stop bit
* 1 = 2 stop bits
* [2:1]: bits 00 = 5 bits
* 01 = 6 bits
* 10 = 7 bits
* 11 = 8 bits
* [0]: parity
*/
/* default: both tx and rx enabled; 8N1 configuration; 1 stop bits */
volatile uint32_t setup = 0x0306 | uart_cfg->parity;
setup |= ((divider) << 16);
UDMA_WRITE_REG(config->base, UDMA_SETUP_REG, setup);
/* start initial reading request to get the dma running */
uint8_t dummy_data[10];
uartTransfer_t dummy_request = {
.data_len = 10,
.data = (uint8_t *)dummy_data,
};
drivers_uart_read(dev, &dummy_request);
return 0;
}
/**
* @return
* - < 0: Error
* - 0: OK
* - > 0: Busy
*/
int32_t drivers_uart_read(const struct device *dev, uartTransfer_t *request)
{
struct sy1xx_uart_config *config = (struct sy1xx_uart_config *)dev->config;
struct sy1xx_uart_data *data = (struct sy1xx_uart_data *)dev->data;
if (request == 0) {
return -1;
}
uint32_t max_read_size = request->data_len;
request->data_len = 0;
if (max_read_size > DEVICE_MAX_BUFFER_SIZE) {
return -3;
}
int32_t ret = 0;
/* rx is ready */
int32_t remaining_bytes = UDMA_READ_REG(config->base, UDMA_RX_SIZE_REG);
int32_t bytes_transferred = (DEVICE_MAX_BUFFER_SIZE - remaining_bytes);
if (bytes_transferred > 0) {
/* copy data to the user buffer */
uint32_t copy_len =
bytes_transferred > max_read_size ? max_read_size : bytes_transferred;
for (uint32_t i = 0; i < copy_len; i++) {
request->data[i] = data->read[i];
}
/* update actual read length */
request->data_len = bytes_transferred;
/* stop and restart receiving */
UDMA_CANCEL_RX(config->base);
/* start another read request, with maximum buffer size */
UDMA_START_RX(config->base, (int32_t)data->read, DEVICE_MAX_BUFFER_SIZE, 0);
/* return: some data received */
ret = 0;
} else {
/* return: (busy) stay in receiving mode */
ret = 1;
}
return ret;
}
/**
* @return
* - < 0: Error
* - 0: OK
* - > 0: Busy
*/
int32_t drivers_uart_write(const struct device *dev, uartTransfer_t *request)
{
struct sy1xx_uart_config *config = (struct sy1xx_uart_config *)dev->config;
struct sy1xx_uart_data *data = (struct sy1xx_uart_data *)dev->data;
if (request == 0) {
return -1;
}
if (request->data_len == 0) {
return -1;
}
if (request->data_len > DEVICE_MAX_BUFFER_SIZE) {
/* more data than possible requested */
return -2;
}
if (0 == UDMA_IS_FINISHED_TX(config->base)) {
/* writing not finished => busy */
return 1;
}
uint32_t remaining_bytes = UDMA_GET_REMAINING_TX(config->base);
if (remaining_bytes != 0) {
UDMA_CANCEL_TX(config->base);
return -3;
}
/* copy the data to transmission buffer */
for (uint32_t i = 0; i < request->data_len; i++) {
data->write[i] = request->data[i];
}
/* start new transmission */
UDMA_START_TX(config->base, (uint32_t)data->write, request->data_len, 0);
/* success */
return 0;
}
/*
* it should be avoided to read single characters only
*/
static int sensry_uart_poll_in(const struct device *dev, unsigned char *c)
{
uartTransfer_t request = {
.data_len = 1,
.data = c,
};
if (0 == drivers_uart_read(dev, &request)) {
return 0;
}
return -1;
}
/*
* it should be avoided to write single characters only
*/
static void sensry_uart_poll_out(const struct device *dev, unsigned char c)
{
uartTransfer_t request = {
.data_len = 1,
.data = &c,
};
while (1) {
if (0 == drivers_uart_write(dev, &request)) {
break;
}
}
}
static int sensry_uart_err_check(const struct device *dev)
{
int err = 0;
return err;
}
static int sy1xx_uart_init(const struct device *dev)
{
struct sy1xx_uart_config *config = (struct sy1xx_uart_config *)dev->config;
struct sy1xx_uart_data *data = (struct sy1xx_uart_data *)dev->data;
for (uint32_t i = 0; i < DEVICE_MAX_BUFFER_SIZE; i++) {
data->write[i] = 0xa5;
data->read[i] = 0xb4;
}
/* UDMA clock enable */
drivers_udma_enable_clock(DRIVERS_UDMA_UART, config->inst);
/* PAD config */
uint32_t pad_config_tx =
PAD_CONFIG(0, PAD_SMT_DISABLE, PAD_SLEW_LOW, PAD_PULLUP_DIS, PAD_PULLDOWN_DIS,
PAD_DRIVE_2PF, PAD_PMOD_NORMAL, PAD_DIR_OUTPUT);
uint32_t pad_config_rx =
PAD_CONFIG(8, PAD_SMT_DISABLE, PAD_SLEW_LOW, PAD_PULLUP_DIS, PAD_PULLDOWN_DIS,
PAD_DRIVE_2PF, PAD_PMOD_NORMAL, PAD_DIR_INPUT);
uint32_t pad_config_cts =
PAD_CONFIG(16, PAD_SMT_DISABLE, PAD_SLEW_LOW, PAD_PULLUP_EN, PAD_PULLDOWN_DIS,
PAD_DRIVE_2PF, PAD_PMOD_NORMAL, PAD_DIR_INPUT);
uint32_t pad_config_rts =
PAD_CONFIG(24, PAD_SMT_DISABLE, PAD_SLEW_LOW, PAD_PULLUP_DIS, PAD_PULLDOWN_DIS,
PAD_DRIVE_2PF, PAD_PMOD_NORMAL, PAD_DIR_OUTPUT);
sys_write32((pad_config_tx | pad_config_rx | pad_config_cts | pad_config_rts),
PAD_CONFIG_ADDR_UART + (config->inst * 4 + 0));
uartConfig_t default_config = {
.baudrate = 1000000,
.parity = DRIVERS_UART_PAR_NONE,
.stopbits = DRIVERS_UART_STOP_1,
};
UDMA_CANCEL_RX(config->base);
UDMA_CANCEL_TX(config->base);
drivers_uart_configure(dev, &default_config);
return 0;
}
static const struct uart_driver_api sy1xx_uart_driver_api = {
.poll_in = sensry_uart_poll_in,
.poll_out = sensry_uart_poll_out,
.err_check = sensry_uart_err_check,
};
#define SYS1XX_UART_INIT(n) \
\
static const struct sy1xx_uart_config sy1xx_uart_##n##_cfg = { \
.base = (uint32_t)DT_INST_REG_ADDR(n), \
.inst = (uint32_t)DT_INST_PROP(n, instance), \
}; \
\
static struct sy1xx_uart_data __attribute__((section(".udma_access"))) \
__aligned(4) sy1xx_uart_##n##_data = { \
\
}; \
\
DEVICE_DT_INST_DEFINE(n, &sy1xx_uart_init, NULL, &sy1xx_uart_##n##_data, \
&sy1xx_uart_##n##_cfg, PRE_KERNEL_1, CONFIG_SERIAL_INIT_PRIORITY, \
&sy1xx_uart_driver_api);
DT_INST_FOREACH_STATUS_OKAY(SYS1XX_UART_INIT)