rtt-f030/bsp/AE210P/driver/uart/uart.c

144 lines
3.3 KiB
C

#include <nds32_intrinsic.h>
#define DEFAULT_BAUDRATE 115200 /* 8n1 */
#define IN8(reg) (uint8_t)((*(volatile unsigned long *)(reg)) & 0x000000FF)
#define READ_CLR(reg) (*(volatile unsigned long *)(reg))
int drv_uart_set_baudrate(int baudrate)
{
unsigned long baud_div; /* baud rate divisor */
unsigned long temp_word;
baud_div = (MB_UCLK / (16 * baudrate));
/* Save LCR temporary */
temp_word = IN8(STUARTC_BASE + UARTC_LCR_OFFSET);
/* Setup dlab bit for baud rate setting */
OUT8(STUARTC_BASE + UARTC_LCR_OFFSET, (temp_word | UARTC_LCR_DLAB));
/* Apply baud rate */
OUT8(STUARTC_BASE + UARTC_DLM_OFFSET, (unsigned char)(baud_div >> 8));
OUT8(STUARTC_BASE + UARTC_DLL_OFFSET, (unsigned char)baud_div);
OUT8(STUARTC_BASE + UARTC_PSR_OFFSET, (unsigned char)1);
/* Restore LCR */
OUT8(STUARTC_BASE + UARTC_LCR_OFFSET, temp_word);
return 0;
}
int drv_uart_is_kbd_hit(void)
{
return IN8(STUARTC_BASE + UARTC_LSR_OFFSET) & UARTC_LSR_RDR;
}
int drv_uart_get_char(void)
{
while (!(IN8(STUARTC_BASE + UARTC_LSR_OFFSET) & UARTC_LSR_RDR))
;
return IN8(STUARTC_BASE + UARTC_RBR_OFFSET);
}
void drv_uart_put_char(int ch)
{
while (!(IN8(STUARTC_BASE + UARTC_LSR_OFFSET) & UARTC_LSR_THRE))
;
OUT8(STUARTC_BASE + UARTC_THR_OFFSET, ch);
}
int drv_uart_init(void)
{
/* Clear everything */
OUT8(STUARTC_BASE + UARTC_IER_OFFSET, 0x0);
OUT8(STUARTC_BASE + UARTC_LCR_OFFSET, 0x0);
/* Setup baud rate */
drv_uart_set_baudrate(DEFAULT_BAUDRATE);
/* Setup parity, data bits, and stop bits */
OUT8(STUARTC_BASE + UARTC_LCR_OFFSET, \
(UARTC_LCR_PARITY_NONE | UARTC_LCR_BITS8 | UARTC_LCR_STOP1));
return 0;
}
/**********************************************
*
* Archer Chang
*
* driver API with reg base
*
***********************************************/
int __drv_uart_set_baudrate(unsigned int regbase, int baudrate)
{
unsigned long baud_div; /* baud rate divisor */
unsigned long temp_word;
baud_div = (MB_UCLK / (16 * baudrate));
/* Save LCR temporary */
temp_word = IN8(regbase + UARTC_LCR_OFFSET);
/* Setup dlab bit for baud rate setting */
OUT8(regbase + UARTC_LCR_OFFSET, (temp_word | UARTC_LCR_DLAB));
/* Apply baud rate */
OUT8(regbase + UARTC_DLM_OFFSET, (unsigned char)(baud_div >> 8));
OUT8(regbase + UARTC_DLL_OFFSET, (unsigned char)baud_div);
OUT8(regbase + UARTC_PSR_OFFSET, (unsigned char)1);
/* Restore LCR */
OUT8(regbase + UARTC_LCR_OFFSET, temp_word);
return 0;
}
int __drv_uart_is_kbd_hit(unsigned int regbase)
{
return IN8(regbase + UARTC_LSR_OFFSET) & UARTC_LSR_RDR;
}
int __drv_uart_get_char(unsigned int regbase)
{
while (!(IN8(regbase + UARTC_LSR_OFFSET) & UARTC_LSR_RDR))
;
return IN8(regbase + UARTC_RBR_OFFSET);
}
void __drv_uart_put_char(unsigned int regbase, int ch)
{
while (!(IN8(regbase + UARTC_LSR_OFFSET) & UARTC_LSR_THRE))
;
OUT8(regbase + UARTC_THR_OFFSET, ch);
}
int __drv_uart_put_char_nowait(unsigned int regbase, int ch)
{
OUT8(regbase + UARTC_THR_OFFSET, ch);
return 1;
}
int __drv_uart_init(unsigned int regbase, int baudrate)
{
/* Clear everything */
OUT8(regbase + UARTC_IER_OFFSET, 0x0);
OUT8(regbase + UARTC_LCR_OFFSET, 0x0);
/* Setup baud rate */
__drv_uart_set_baudrate(regbase, baudrate);
/* Setup parity, data bits, and stop bits */
OUT8(regbase + UARTC_LCR_OFFSET, \
(UARTC_LCR_PARITY_NONE | UARTC_LCR_BITS8 | UARTC_LCR_STOP1));
return 0;
}