linux-sg2042/arch/mips/ath79/early_printk.c

37 lines
862 B
C

/*
* Atheros AR71XX/AR724X/AR913X SoC early printk support
*
* Copyright (C) 2008-2010 Gabor Juhos <juhosg@openwrt.org>
* Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*/
#include <linux/io.h>
#include <linux/serial_reg.h>
#include <asm/addrspace.h>
#include <asm/mach-ath79/ar71xx_regs.h>
static inline void prom_wait_thre(void __iomem *base)
{
u32 lsr;
do {
lsr = __raw_readl(base + UART_LSR * 4);
if (lsr & UART_LSR_THRE)
break;
} while (1);
}
void prom_putchar(unsigned char ch)
{
void __iomem *base = (void __iomem *)(KSEG1ADDR(AR71XX_UART_BASE));
prom_wait_thre(base);
__raw_writel(ch, base + UART_TX * 4);
prom_wait_thre(base);
}