/*
* Copyright (c) 2006-2021, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2006-08-23 Bernard first version
* 2009-05-14 Bernard add RT-THread device interface
*/
#include <rthw.h>
#include <rtthread.h>
#include "AT91SAM7S.h"
#include "serial.h"
/**
* @addtogroup AT91SAM7
*/
/*@{*/
typedef volatile rt_uint32_t REG32;
struct rt_at91serial_hw
{
REG32 US_CR; // Control Register
REG32 US_MR; // Mode Register
REG32 US_IER; // Interrupt Enable Register
REG32 US_IDR; // Interrupt Disable Register
REG32 US_IMR; // Interrupt Mask Register
REG32 US_CSR; // Channel Status Register
REG32 US_RHR; // Receiver Holding Register
REG32 US_THR; // Transmitter Holding Register
REG32 US_BRGR; // Baud Rate Generator Register
REG32 US_RTOR; // Receiver Time-out Register
REG32 US_TTGR; // Transmitter Time-guard Register
REG32 Reserved0[5]; //
REG32 US_FIDI; // FI_DI_Ratio Register
REG32 US_NER; // Nb Errors Register
REG32 Reserved1[1]; //
REG32 US_IF; // IRDA_FILTER Register
REG32 Reserved2[44]; //
REG32 US_RPR; // Receive Pointer Register
REG32 US_RCR; // Receive Counter Register
REG32 US_TPR; // Transmit Pointer Register
REG32 US_TCR; // Transmit Counter Register
REG32 US_RNPR; // Receive Next Pointer Register
REG32 US_RNCR; // Receive Next Counter Register
REG32 US_TNPR; // Transmit Next Pointer Register
REG32 US_TNCR; // Transmit Next Counter Register
REG32 US_PTCR; // PDC Transfer Control Register
REG32 US_PTSR; // PDC Transfer Status Register
};
struct rt_at91serial
{
struct rt_device parent;
struct rt_at91serial_hw* hw_base;
rt_uint16_t peripheral_id;
rt_uint32_t baudrate;
/* reception field */
rt_uint16_t save_index, read_index;
rt_uint8_t rx_buffer[RT_UART_RX_BUFFER_SIZE];
};
#ifdef RT_USING_UART1
struct rt_at91serial serial1;
#endif
#ifdef RT_USING_UART2
struct rt_at91serial serial2;
#endif
static void rt_hw_serial_isr(int irqno)
{
rt_base_t level;
struct rt_device* device;
struct rt_at91serial* serial = RT_NULL;
if (irqno == AT91C_ID_US0)
{
#ifdef RT_USING_UART1
/* serial 1 */
serial = &serial1;
#endif
}
else if (irqno == AT91C_ID_US1)
{
#ifdef RT_USING_UART2
/* serial 2 */
serial = &serial2;
#endif
}
RT_ASSERT(serial != RT_NULL);
/* get generic device object */
device = (rt_device_t)serial;
/* disable interrupt */
level = rt_hw_interrupt_disable();
/* get received character */
serial->rx_buffer[serial->save_index] = serial->hw_base->US_RHR;
/* move to next position */
serial->save_index ++;
if (serial->save_index >= RT_UART_RX_BUFFER_SIZE)
serial->save_index = 0;
/* if the next position is read index, discard this 'read char' */
if (serial->save_index == serial->read_index)
{
serial->read_index ++;
if (serial->read_index >= RT_UART_RX_BUFFER_SIZE)
serial->read_index = 0;
}
/* enable interrupt */
rt_hw_interrupt_enable(level);
/* indicate to upper layer application */
if (device->rx_indicate != RT_NULL)
device->rx_indicate(device, 1);
/* ack interrupt */
AT91C_AIC_EOICR = 1;
}
static rt_err_t rt_serial_init (rt_device_t dev)
{
rt_uint32_t bd;
struct rt_at91serial* serial = (struct rt_at91serial*) dev;
RT_ASSERT(serial != RT_NULL);
/* must be US0 or US1 */
RT_ASSERT(((serial->peripheral_id == AT91C_ID_US0) ||
(serial->peripheral_id == AT91C_ID_US1)));
/* Enable Clock for USART */
AT91C_PMC_PCER = 1 << serial->peripheral_id;
/* Enable RxD0 and TxDO Pin */
if (serial->peripheral_id == AT91C_ID_US0)
{
/* set pinmux */
AT91C_PIO_PDR = (1 << 5) | (1 << 6);
}
else if (serial->peripheral_id == AT91C_ID_US1)
{
/* set pinmux */
AT91C_PIO_PDR = (1 << 21) | (1 << 22);
}
serial->hw_base->US_CR = AT91C_US_RSTRX | /* Reset Receiver */
AT91C_US_RSTTX | /* Reset Transmitter */
AT91C_US_RXDIS | /* Receiver Disable */
AT91C_US_TXDIS; /* Transmitter Disable */
serial->hw_base->US_MR = AT91C_US_USMODE_NORMAL | /* Normal Mode */
AT91C_US_CLKS_CLOCK | /* Clock = MCK */
AT91C_US_CHRL_8_BITS | /* 8-bit Data */
AT91C_US_PAR_NONE | /* No Parity */
AT91C_US_NBSTOP_1_BIT; /* 1 Stop Bit */
/* set baud rate divisor */
bd = ((MCK*10)/(serial->baudrate * 16));
if ((bd % 10) >= 5) bd = (bd / 10) + 1;
else bd /= 10;
serial->hw_base->US_BRGR = bd;
serial->hw_base->US_CR = AT91C_US_RXEN | /* Receiver Enable */
AT91C_US_TXEN; /* Transmitter Enable */
/* reset rx index */
serial->save_index = 0;
serial->read_index = 0;
/* reset rx buffer */
rt_memset(serial->rx_buffer, 0, RT_UART_RX_BUFFER_SIZE);
return RT_EOK;
}
static rt_err_t rt_serial_open(rt_device_t dev, rt_uint16_t oflag)
{
struct rt_at91serial *serial = (struct rt_at91serial*)dev;
RT_ASSERT(serial != RT_NULL);
if (dev->flag & RT_DEVICE_FLAG_INT_RX)
{
/* enable UART rx interrupt */
serial->hw_base->US_IER = 1 << 0; /* RxReady interrupt */
serial->hw_base->US_IMR |= 1 << 0; /* umask RxReady interrupt */
/* install UART handler */
rt_hw_interrupt_install(serial->peripheral_id, rt_hw_serial_isr, RT_NULL);
AT91C_AIC_SMR(serial->peripheral_id) = 5 | (0x01 << 5);
rt_hw_interrupt_umask(serial->peripheral_id);
}
return RT_EOK;
}
static rt_err_t rt_serial_close(rt_device_t dev)
{
struct rt_at91serial *serial = (struct rt_at91serial*)dev;
RT_ASSERT(serial != RT_NULL);
if (dev->flag & RT_DEVICE_FLAG_INT_RX)
{
/* disable interrupt */
serial->hw_base->US_IDR = 1 << 0; /* RxReady interrupt */
serial->hw_base->US_IMR &= ~(1 << 0); /* mask RxReady interrupt */
}
return RT_EOK;
}
static rt_ssize_t rt_serial_read (rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
{
rt_uint8_t* ptr;
struct rt_at91serial *serial = (struct rt_at91serial*)dev;
RT_ASSERT(serial != RT_NULL);
/* point to buffer */
ptr = (rt_uint8_t*) buffer;
if (dev->flag & RT_DEVICE_FLAG_INT_RX)
{
while (size)
{
/* interrupt receive */
rt_base_t level;
/* disable interrupt */
level = rt_hw_interrupt_disable();
if (serial->read_index != serial->save_index)
{
*ptr = serial->rx_buffer[serial->read_index];
serial->read_index ++;
if (serial->read_index >= RT_UART_RX_BUFFER_SIZE)
serial->read_index = 0;
}
else
{
/* no data in rx buffer */
/* enable interrupt */
rt_hw_interrupt_enable(level);
break;
}
/* enable interrupt */
rt_hw_interrupt_enable(level);
ptr ++; size --;
}
return (rt_uint32_t)ptr - (rt_uint32_t)buffer;
}
else if (dev->flag & RT_DEVICE_FLAG_DMA_RX)
{
/* not support right now */
RT_ASSERT(0);
}
else
{
/* poll mode */
while (size)
{
/* Wait for Full Rx Buffer */
while (!(serial->hw_base->US_CSR & AT91C_US_RXRDY));
/* Read Character */
*ptr = serial->hw_base->US_RHR;
ptr ++;
size --;
}
return (rt_size_t)ptr - (rt_size_t)buffer;
}
return 0;
}
static rt_ssize_t rt_serial_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
{
rt_uint8_t* ptr;
struct rt_at91serial *serial = (struct rt_at91serial*)dev;
RT_ASSERT(serial != RT_NULL);
ptr = (rt_uint8_t*) buffer;
if (dev->open_flag & RT_DEVICE_OFLAG_WRONLY)
{
if (dev->flag & RT_DEVICE_FLAG_STREAM)
{
/* it's a stream mode device */
while (size)
{
/* stream mode */
if (*ptr == '\n')
{
while (!(serial->hw_base->US_CSR & AT91C_US_TXRDY));
serial->hw_base->US_THR = '\r';
}
/* Wait for Empty Tx Buffer */
while (!(serial->hw_base->US_CSR & AT91C_US_TXRDY));
/* Transmit Character */
serial->hw_base->US_THR = *ptr;
ptr ++; size --;
}
}
else
{
while (size)
{
/* Wait for Empty Tx Buffer */
while (!(serial->hw_base->US_CSR & AT91C_US_TXRDY));
/* Transmit Character */
serial->hw_base->US_THR = *ptr;
ptr ++; size --;
}
}
}
return (rt_size_t)ptr - (rt_size_t)buffer;
}
static rt_err_t rt_serial_control (rt_device_t dev, int cmd, void *args)
{
return RT_EOK;
}
rt_err_t rt_hw_serial_init()
{
rt_device_t device;
#ifdef RT_USING_UART1
device = (rt_device_t) &serial1;
/* init serial device private data */
serial1.hw_base = (struct rt_at91serial_hw*)AT91C_BASE_US0;
serial1.peripheral_id = AT91C_ID_US0;
serial1.baudrate = 115200;
/* set device virtual interface */
device->init = rt_serial_init;
device->open = rt_serial_open;
device->close = rt_serial_close;
device->read = rt_serial_read;
device->write = rt_serial_write;
device->control = rt_serial_control;
/* register uart1 on device subsystem */
rt_device_register(device, "uart1", RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX);
#endif
#ifdef RT_USING_UART2
device = (rt_device_t) &serial2;
serial2.hw_base = (struct rt_at91serial_hw*)AT91C_BASE_US1;
serial2.peripheral_id = AT91C_ID_US1;
serial2.baudrate = 115200;
/* set device virtual interface */
device->init = rt_serial_init;
device->open = rt_serial_open;
device->close = rt_serial_close;
device->read = rt_serial_read;
device->write = rt_serial_write;
device->control = rt_serial_control;
/* register uart2 on device subsystem */
rt_device_register(device, "uart2", RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX);
#endif
return RT_EOK;
}
/*@}*/