embox

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/**
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 * @file
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 * @brief Serial driver for x86 (compatible with 16550)
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 *
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 * @date 12.04.10
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 * @author Nikolay Korotky
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 */
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#include <stdint.h>
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#include <asm/io.h>
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#include <drivers/serial/uart_dev.h>
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#include "i8250.h"
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static uint8_t calc_line_stat(const struct uart_params *params) {
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	uint8_t line_stat;
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	uint32_t flags;
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	line_stat = 0;
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	flags = params->uart_param_flags;
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	if((flags & UART_PARAM_FLAGS_PARITY_NONE)) {
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		line_stat |= UART_NO_PARITY;
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	}
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	if(flags & UART_PARAM_FLAGS_8BIT_WORD) {
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		line_stat |= UART_8BITS_WORD;
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	}
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	if((flags & UART_PARAM_FLAGS_2_STOP)) {
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		line_stat |= UART_2_STOP_BIT;
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	} else {
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		line_stat |= UART_1_STOP_BIT;
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	}
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	return line_stat;
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}
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static int i8250_setup(struct uart *dev, const struct uart_params *params) {
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	uint8_t line_stat;
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	line_stat = calc_line_stat(params);
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	line_stat = UART_NO_PARITY | UART_8BITS_WORD | UART_1_STOP_BIT;
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	/* Turn off the interrupt */
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	out8(0x0, dev->base_addr + UART_IER);
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	/* Set DLAB */
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	out8(UART_DLAB, dev->base_addr + UART_LCR);
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	/* Set the baud rate */
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	out8(DIVISOR(params->baud_rate) & 0xFF, dev->base_addr + UART_DLL);
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	out8((DIVISOR(params->baud_rate) >> 8) & 0xFF, dev->base_addr + UART_DLH);
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	/* Set the line status */
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	out8(line_stat, dev->base_addr + UART_LCR);
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	/* Uart enable FIFO */
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	out8(UART_ENABLE_FIFO, dev->base_addr + UART_FCR);
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	/* Uart enable modem (turn on DTR, RTS, and OUT2) */
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	out8(UART_ENABLE_MODEM, dev->base_addr + UART_MCR);
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	/*enable rx interrupt*/
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	if (params->uart_param_flags & UART_PARAM_FLAGS_USE_IRQ) {
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		/*enable rx interrupt*/
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		out8(UART_IER_RX_ENABLE, dev->base_addr + UART_IER);
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	}
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	return 0;
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}
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static int i8250_irq_en(struct uart *dev, const struct uart_params *params) {
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	/*enable rx interrupt*/
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	if (params->uart_param_flags & UART_PARAM_FLAGS_USE_IRQ) {
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		/*enable rx interrupt*/
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		out8(UART_IER_RX_ENABLE, dev->base_addr + UART_IER);
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	}
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	return 0;
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}
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static int i8250_irq_dis(struct uart *dev, const struct uart_params *params) {
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	if (params->uart_param_flags & UART_PARAM_FLAGS_USE_IRQ) {
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		/*disable rx interrupt*/
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		out8(0, dev->base_addr + UART_IER);
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	}
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	return 0;
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}
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static int i8250_putc(struct uart *dev, int ch) {
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	while (!(in8(dev->base_addr + UART_LSR) & UART_EMPTY_TX));
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	out8((uint8_t) ch, dev->base_addr + UART_TX);
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	return 0;
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}
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static int i8250_has_symbol(struct uart *dev) {
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	return in8(dev->base_addr + UART_LSR) & UART_DATA_READY;
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}
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static int i8250_getc(struct uart *dev) {
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	return in8(dev->base_addr + UART_RX);
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}
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const struct uart_ops i8250_uart_ops = {
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		.uart_getc = i8250_getc,
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		.uart_putc = i8250_putc,
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		.uart_hasrx = i8250_has_symbol,
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		.uart_setup = i8250_setup,
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		.uart_irq_en = i8250_irq_en,
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		.uart_irq_dis = i8250_irq_dis,
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};
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