embox

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/**
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 * @file
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 * @brief
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 *
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 * @author  Anton Kozlov
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 * @date    03.07.2012
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 */
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#include <stdint.h>
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#include <drivers/gpio/gpio.h>
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#include <hal/reg.h>
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#include <hal/system.h>
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#include <drivers/diag.h>
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#include <drivers/serial/diag_serial.h>
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#include <embox/unit.h>
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#include <drivers/serial/uart_dev.h>
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EMBOX_UNIT_INIT(stm32uart_mod_init);
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struct uart_stm32 {
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	uint16_t sr;
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	uint16_t reserv0;
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	uint16_t dr;
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	uint16_t reserv1;
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	uint16_t brr;
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	uint16_t reserv2;
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	uint16_t cr1;
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	uint16_t reserv3;
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	uint16_t cr2;
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	uint16_t reserv4;
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	uint16_t cr3;
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	uint16_t reserv5;
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	uint16_t gtpr;
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} __attribute__ ((packed));
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#define RCC_APB1RSTR  0x40021010
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#define RCC_APB1PWR   0x10000000
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#define RCC_APB2ENR   0x40021018
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#define RCC_APB2GPIOC 0x00000010
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#define RCC_APB2GPIOx 0x000001fc
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#define RCC_APB2AFIO  0x00000001
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#define UART0 (0x40013800)
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#define UART_GPIO GPIO_PORT_A
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#define TX_PIN  (1 << 9)
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#define RX_PIN  (1 << 10)
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#define CTS_PIN (1 << 11)
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#define RTS_PIN (1 << 12)
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#define USART_FLAG_RXNE (1 << 5)
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#define USART_FLAG_TXE (1 << 7)
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#define USART_FLAG_UE (1 << 13)	/* USART enable		*/
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#define USART_FLAG_RE (1 << 2)	/* Receive enable	*/
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#define USART_FLAG_TE (1 << 3)	/* Transmit enable	*/
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#define RCC_APB2ENR_USART1EN (1 << 14)
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static int stm32_uart_putc(struct uart *dev, int ch) {
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	struct uart_stm32 *uart = (struct uart_stm32 *) dev->base_addr;
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	while (!(REG_LOAD(&uart->sr) & USART_FLAG_TXE)) { }
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	REG_STORE(&uart->dr, ch);
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	return 0;
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}
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static int stm32_uart_hasrx(struct uart *dev) {
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	struct uart_stm32 *uart = (struct uart_stm32 *) dev->base_addr;
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	return (REG_LOAD(&uart->sr) & USART_FLAG_RXNE);
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}
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static int stm32_uart_getc(struct uart *dev) {
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	struct uart_stm32 *uart = (struct uart_stm32 *) dev->base_addr;
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	return REG_LOAD(&uart->dr);
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}
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static int stm32_uart_setup(struct uart *dev, const struct uart_params *params) {
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	struct uart_stm32 *uart = (struct uart_stm32 *) dev->base_addr;
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	REG_ORIN(RCC_APB1RSTR,RCC_APB1PWR);
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	REG_ORIN(RCC_APB2ENR,RCC_APB2GPIOx);
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	REG_ORIN(RCC_APB2ENR,RCC_APB2AFIO);
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	REG_ORIN(RCC_APB2ENR,RCC_APB2ENR_USART1EN);
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	gpio_setup_mode(UART_GPIO, TX_PIN ,
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			GPIO_MODE_OUT | GPIO_MODE_OUT_ALTERNATE);
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	gpio_setup_mode(UART_GPIO, RX_PIN, GPIO_MODE_IN);
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	REG_STORE(&uart->brr, SYS_CLOCK / params->baud_rate);
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	REG_ORIN(&uart->cr1, USART_FLAG_RE | USART_FLAG_TE);
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	REG_ORIN(&uart->cr1, USART_FLAG_UE);
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	return 0;
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}
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static const struct uart_ops stm32_uart_ops = {
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		.uart_getc = stm32_uart_getc,
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		.uart_putc = stm32_uart_putc,
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		.uart_hasrx = stm32_uart_hasrx,
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		.uart_setup = stm32_uart_setup,
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};
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static struct uart stm32_uart0 = {
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		.uart_ops = &stm32_uart_ops,
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		.irq_num = 0,
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		.base_addr = UART0,
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};
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static const struct uart_params uart_defparams = {
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		.baud_rate = OPTION_GET(NUMBER,baud_rate),
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		.uart_param_flags = UART_PARAM_FLAGS_8BIT_WORD,
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};
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DIAG_SERIAL_DEF(&stm32_uart0, &uart_defparams);
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static int stm32uart_mod_init(void) {
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	/*if (!uart_register(&stm32_uart0, &uart_defparams)) {*/
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		/*return -1;*/
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	/*}*/
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	return 0;
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}
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