rt-thread/bsp/qemu-virt64-riscv/driver/drv_uart.c

167 lines
3.8 KiB
C

/*
* Copyright (c) 2006-2020, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
*/
#include <rthw.h>
#include <rtdevice.h>
#include <rtthread.h>
#include "board.h"
#include "drv_uart.h"
#include <stdio.h>
#ifdef RT_USING_USERSPACE
#include <ioremap.h>
#endif
#include "sbi.h"
struct device_uart
{
rt_ubase_t hw_base;
rt_uint32_t irqno;
};
void *uart0_base = (void*)0x10000000;
struct rt_serial_device serial0;
struct device_uart uart0;
void uart_init(void)
{
rt_uint32_t div = UART_REFERENCE_CLOCK / (UART_DEFAULT_BAUDRATE * 16);
write8_uart0(UART_IER, 0x00);
write8_uart0(UART_LCR, UART_LCR_BAUD_LATCH);
// LSB
write8_uart0(0, div & 0xff);
// MSB
write8_uart0(1, (div >> 8) & 0xff);
// set word length to 8 bits, no parity
write8_uart0(UART_LCR, UART_LCR_EIGHT_BITS);
write8_uart0(UART_FCR, UART_FCR_FIFO_ENABLE | UART_FCR_FIFO_CLEAR);
return;
}
static rt_err_t _uart_configure(struct rt_serial_device *serial, struct serial_configure *cfg)
{
uart_init();
return (RT_EOK);
}
static rt_err_t _uart_control(struct rt_serial_device *serial, int cmd, void *arg)
{
struct device_uart *uart = (struct device_uart*)serial->parent.user_data;
switch (cmd)
{
case RT_DEVICE_CTRL_CLR_INT:
if ((size_t)arg == RT_DEVICE_FLAG_INT_RX)
{
rt_uint8_t value = read8_uart0(UART_IER);
write8_uart0(UART_IER, value & ~UART_IER_RX_ENABLE);
}
break;
case RT_DEVICE_CTRL_SET_INT:
if ((size_t)arg == RT_DEVICE_FLAG_INT_RX)
{
rt_uint8_t value = read8_uart0(UART_IER);
write8_uart0(UART_IER, value | UART_IER_RX_ENABLE);
}
break;
}
return (RT_EOK);
}
static int _uart_putc(struct rt_serial_device *serial, char c)
{
struct device_uart *uart;
uart = (struct device_uart*)serial->parent.user_data;
// wait for Transmit Holding Empty to be set in LSR.
while((read8_uart0(UART_LSR) & UART_LSR_TX_IDLE) == 0)
;
write8_uart0(UART_THR, c);
return (1);
}
static int _uart_getc(struct rt_serial_device *serial)
{
struct device_uart *uart;
volatile rt_uint32_t lsr;
int ch = -1;
uart = (struct device_uart*)serial->parent.user_data;
lsr = read8_uart0(UART_LSR);
if (lsr & UART_LSR_RX_READY)
{
ch = read8_uart0(UART_RHR);
}
return ch;
}
const struct rt_uart_ops _uart_ops = {
_uart_configure,
_uart_control,
_uart_putc,
_uart_getc,
// TODO: add DMA support
RT_NULL};
static void rt_hw_uart_isr(int irqno, void *param)
{
rt_ubase_t level = rt_hw_interrupt_disable();
struct rt_serial_device *serial = (struct rt_serial_device *)param;
rt_hw_serial_isr(serial, RT_SERIAL_EVENT_RX_IND);
rt_hw_interrupt_enable(level);
}
/*
* UART Initiation
*/
int rt_hw_uart_init(void)
{
struct rt_serial_device *serial;
struct device_uart *uart;
struct serial_configure config = RT_SERIAL_CONFIG_DEFAULT;
#ifdef RT_USING_USERSPACE
uart0_base = rt_ioremap(uart0_base, 4096);
#endif
// register device
serial = &serial0;
uart = &uart0;
serial->ops = &_uart_ops;
serial->config = config;
serial->config.baud_rate = UART_DEFAULT_BAUDRATE;
uart->hw_base = (rt_ubase_t)uart0_base;
uart->irqno = 0x0a;
rt_hw_serial_register(serial,
RT_CONSOLE_DEVICE_NAME,
RT_DEVICE_FLAG_STREAM | RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX,
uart);
rt_hw_interrupt_install(uart->irqno, rt_hw_uart_isr, serial, RT_CONSOLE_DEVICE_NAME);
rt_hw_interrupt_umask(uart->irqno);
return 0;
}
/* WEAK for SDK 0.5.6 */
rt_weak void uart_debug_init(int uart_channel)
{
}