diff options
Diffstat (limited to 'os/drivers/uart/stm32f7_uart.c')
| -rw-r--r-- | os/drivers/uart/stm32f7_uart.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/os/drivers/uart/stm32f7_uart.c b/os/drivers/uart/stm32f7_uart.c new file mode 100644 index 00000000..76f67ae9 --- /dev/null +++ b/os/drivers/uart/stm32f7_uart.c @@ -0,0 +1,168 @@ +#include <arch/aarch32/armv7e_m/stm32f7/stm32f769xx.h> +#include <arch/sys_io.h> + +#include <drivers/clock/stm32f769_clocks.h> +#include <drivers/clock/stm32f769_clock_control.h> + +#include <string.h> + +#include "uart.h" +#include "stm32f7_uart.h" + +#define UART_BRR_MIN 0x10U /* UART BRR minimum authorized value */ +#define UART_BRR_MAX 0x0000FFFFU /* UART BRR maximum authorized value */ + +inline static void __uart_disable(struct device *dev) { + USART_TypeDef *p = dev->devptr; + p->CR1 &= ~USART_CR1_UE; +} + +inline static void __uart_enable(struct device *dev) { + USART_TypeDef *p = dev->devptr; + p->CR1 |= USART_CR1_UE; +} + +int stm32f7_uart_init(struct device *dev) { + USART_TypeDef *p = dev->devptr; + stm32f7_uart_deinit(dev); + + uint32_t clk_rate = 0; + uint32_t parity = 0; + uint32_t stop_bits = 0; + uint32_t word_length = 0; + + struct uart_data *uart = (struct uart_data *)dev->data; + + switch ((uint32_t)p) { + case USART1_BASE: + stm32f769_clock_control_get_rate(STM32F769_CLOCK_USART1, &clk_rate); + break; + case USART2_BASE: + stm32f769_clock_control_get_rate(STM32F769_CLOCK_USART2, &clk_rate); + break; + case USART3_BASE: + stm32f769_clock_control_get_rate(STM32F769_CLOCK_USART3, &clk_rate); + break; + case UART4_BASE: + stm32f769_clock_control_get_rate(STM32F769_CLOCK_UART4, &clk_rate); + break; + case UART5_BASE: + stm32f769_clock_control_get_rate(STM32F769_CLOCK_UART5, &clk_rate); + break; + case USART6_BASE: + stm32f769_clock_control_get_rate(STM32F769_CLOCK_USART6, &clk_rate); + break; + case UART7_BASE: + stm32f769_clock_control_get_rate(STM32F769_CLOCK_UART7, &clk_rate); + break; + case UART8_BASE: + stm32f769_clock_control_get_rate(STM32F769_CLOCK_UART8, &clk_rate); + break; + default: + return -1; + } + + switch (uart->data_bits) { + case UART_CFG_DATA_BITS_7: + word_length = USART_CR1_M1; + break; + case UART_CFG_DATA_BITS_8: + word_length = 0; + break; + case UART_CFG_DATA_BITS_9: + word_length = USART_CR1_M0; + break; + case UART_CFG_DATA_BITS_5: + case UART_CFG_DATA_BITS_6: + default: + return -1; + } + + switch (uart->parity) { + case UART_CFG_PARITY_NONE: + parity = 0; + break; + case UART_CFG_PARITY_ODD: + parity = USART_CR1_PCE; + break; + case UART_CFG_PARITY_EVEN: + parity = (USART_CR1_PCE | USART_CR1_PS); + break; + case UART_CFG_PARITY_MARK: + case UART_CFG_PARITY_SPACE: + default: + return -1; + } + + switch (uart->stop_bits) { + case UART_CFG_STOP_BITS_0_5: + stop_bits = USART_CR2_STOP_0; + break; + case UART_CFG_STOP_BITS_1: + stop_bits = 0; + break; + case UART_CFG_STOP_BITS_1_5: + stop_bits = (USART_CR2_STOP_0 | USART_CR2_STOP_1); + break; + case UART_CFG_STOP_BITS_2: + stop_bits = USART_CR2_STOP_1; + break; + default: + return -1; + } + + uint32_t cr1 = word_length | parity | USART_CR1_TE | USART_CR1_RE; + WRITE_REG(p->CR1, cr1); + cr1 = READ_REG(p->CR1); + + uint32_t cr2 = stop_bits; + WRITE_REG(p->CR2, cr2); + cr2 = READ_REG(p->CR2); + + uint32_t cr3 = 0; + WRITE_REG(p->CR3, cr3); + cr3 = READ_REG(p->CR3); + + uint32_t div = (clk_rate + ((uart->baudrate)/2U)) / (uart->baudrate); + if ((div >= UART_BRR_MIN) && (div <= UART_BRR_MAX)) { + p->BRR = (uint16_t)div; + } else { + return -1; + } + + CLEAR_BIT(p->CR2, (USART_CR2_LINEN | USART_CR2_CLKEN)); + CLEAR_BIT(p->CR3, (USART_CR3_SCEN | USART_CR3_HDSEL | USART_CR3_IREN)); + + __uart_enable(dev); + return 0; +} + +int stm32f7_uart_deinit(struct device *dev) { + __uart_disable(dev); + USART_TypeDef *p = dev->devptr; + p->CR1 = 0x0U; + p->CR2 = 0x0U; + p->CR3 = 0x0U; + return 0; +} + +void stm32f7_uart_poll_out8(const struct device *dev, unsigned char ch) +{ + USART_TypeDef *p = dev->devptr; + + while ((p->ISR & USART_ISR_TXE) == 0) { + } + + p->TDR = ch; +} + +void stm32f7_uart_tx_buffer(const struct device *dev, char *buffer, unsigned int len) { + unsigned int i = 0; + for (;i < len; i++) { + stm32f7_uart_poll_out8(dev, buffer[i]); + } +} + +void stm32f7_uart_tx(const struct device *dev, char *buffer) { + stm32f7_uart_tx_buffer(dev, buffer, strlen(buffer)); +} |