early_printk.c

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/*
 *  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.
 *
 *  Copyright (C) 2010 John Crispin <[email protected]>
 */

#include <linux/cpu.h>
#include <lantiq_soc.h>

#define ASC_BUF     1024
#define LTQ_ASC_FSTAT   ((u32 *)(LTQ_EARLY_ASC + 0x0048))
#ifdef __BIG_ENDIAN
#define LTQ_ASC_TBUF    ((u32 *)(LTQ_EARLY_ASC + 0x0020 + 3))
#else
#define LTQ_ASC_TBUF    ((u32 *)(LTQ_EARLY_ASC + 0x0020))
#endif
#define TXMASK      0x3F00
#define TXOFFSET    8

void prom_putchar(char c)
{
    unsigned long flags;

    local_irq_save(flags);
    do { } while ((ltq_r32(LTQ_ASC_FSTAT) & TXMASK) >> TXOFFSET);
    if (c == '\n')
        ltq_w8('\r', LTQ_ASC_TBUF);
    ltq_w8(c, LTQ_ASC_TBUF);
    local_irq_restore(flags);
}