Root/target/linux/ar71xx/files/arch/mips/ar71xx/early_printk.c

1/*
2 * Atheros AR71xx SoC early printk support
3 *
4 * Copyright (C) 2008-2009 Gabor Juhos <juhosg@openwrt.org>
5 * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published
9 * by the Free Software Foundation.
10 */
11
12#include <linux/io.h>
13#include <linux/serial_reg.h>
14#include <asm/addrspace.h>
15
16#include <asm/mach-ar71xx/ar71xx.h>
17
18#define UART_READ(r) \
19    __raw_readl((void __iomem *)(KSEG1ADDR(AR71XX_UART_BASE) + 4 * (r)))
20
21#define UART_WRITE(r, v) \
22    __raw_writel((v), (void __iomem *)(KSEG1ADDR(AR71XX_UART_BASE) + 4*(r)))
23
24void prom_putchar(unsigned char ch)
25{
26    while (((UART_READ(UART_LSR)) & UART_LSR_THRE) == 0);
27    UART_WRITE(UART_TX, ch);
28    while (((UART_READ(UART_LSR)) & UART_LSR_THRE) == 0);
29}
30
31

Archive Download this file



interactive