arch/mips/lantiq/early_printk.c

   1 /*
   2  *  This program is free software; you can redistribute it and/or modify it
   3  *  under the terms of the GNU General Public License version 2 as published
   4  *  by the Free Software Foundation.
   5  *
   6  *  Copyright (C) 2010 John Crispin <blogic@openwrt.org>
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/cpu.h>
  11
  12 #include <lantiq.h>
  13 #include <lantiq_soc.h>
  14
  15 /* no ioremap possible at this early stage, lets use KSEG1 instead  */
  16 #define LTQ_ASC_BASE    KSEG1ADDR(LTQ_ASC1_BASE_ADDR)
  17 #define ASC_BUF         1024
  18 #define LTQ_ASC_FSTAT   ((u32 *)(LTQ_ASC_BASE + 0x0048))
  19 #define LTQ_ASC_TBUF    ((u32 *)(LTQ_ASC_BASE + 0x0020))
  20 #define TXMASK          0x3F00
  21 #define TXOFFSET        8
  22
  23 void prom_putchar(char c)
  24 {
  25         unsigned long flags;
  26
  27         local_irq_save(flags);
  28         do { } while ((ltq_r32(LTQ_ASC_FSTAT) & TXMASK) >> TXOFFSET);
  29         if (c == '\n')
  30                 ltq_w32('\r', LTQ_ASC_TBUF);
  31         ltq_w32(c, LTQ_ASC_TBUF);
  32         local_irq_restore(flags);
  33 }