linux/arch/mips/ath25/early_printk.c
Sergey Ryazanov 8aaa7278c0 MIPS: ath25: add early printk support
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: Linux MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/8241/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:27 +01:00

45 lines
1.0 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2010 Gabor Juhos <juhosg@openwrt.org>
*/
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/serial_reg.h>
#include "devices.h"
#include "ar2315_regs.h"
#include "ar5312_regs.h"
static inline void prom_uart_wr(void __iomem *base, unsigned reg,
unsigned char ch)
{
__raw_writel(ch, base + 4 * reg);
}
static inline unsigned char prom_uart_rr(void __iomem *base, unsigned reg)
{
return __raw_readl(base + 4 * reg);
}
void prom_putchar(unsigned char ch)
{
static void __iomem *base;
if (unlikely(base == NULL)) {
if (is_ar2315())
base = (void __iomem *)(KSEG1ADDR(AR2315_UART0_BASE));
else
base = (void __iomem *)(KSEG1ADDR(AR5312_UART0_BASE));
}
while ((prom_uart_rr(base, UART_LSR) & UART_LSR_THRE) == 0)
;
prom_uart_wr(base, UART_TX, ch);
while ((prom_uart_rr(base, UART_LSR) & UART_LSR_THRE) == 0)
;
}