/* early printk support * * Copyright (c) 2009 Philippe Vachon <philippe@cowpig.ca> * Copyright (c) 2009 Lemote Inc. * Author: Wu Zhangjin, wuzhangjin@gmail.com * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. */ #include <linux/serial_reg.h> #include <loongson.h> #define PORT(base, offset) (u8 *)(base + offset) static inline unsigned int serial_in(unsigned char *base, int offset) { return readb(PORT(base, offset)); } static inline void serial_out(unsigned char *base, int offset, int value) { writeb(value, PORT(base, offset)); } void prom_putchar(char c) { int timeout; unsigned char *uart_base; uart_base = (unsigned char *)_loongson_uart_base[0]; timeout = 1024; while (((serial_in(uart_base, UART_LSR) & UART_LSR_THRE) == 0) && (timeout-- > 0)) ; serial_out(uart_base, UART_TX, c); }