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12#include <linux/serial_reg.h>
13
14#include <loongson.h>
15
16#define PORT(base, offset) (u8 *)(base + offset)
17
18static inline unsigned int serial_in(unsigned char *base, int offset)
19{
20 return readb(PORT(base, offset));
21}
22
23static inline void serial_out(unsigned char *base, int offset, int value)
24{
25 writeb(value, PORT(base, offset));
26}
27
28void prom_putchar(char c)
29{
30 int timeout;
31 unsigned char *uart_base;
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33 uart_base = (unsigned char *)_loongson_uart_base;
34 timeout = 1024;
35
36 while (((serial_in(uart_base, UART_LSR) & UART_LSR_THRE) == 0) &&
37 (timeout-- > 0))
38 ;
39
40 serial_out(uart_base, UART_TX, c);
41}
42