arch/mips/bcm63xx/early_printk.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
   7  */
   8
   9 #include <linux/init.h>
  10 #include <bcm63xx_io.h>
  11 #include <bcm63xx_regs.h>
  12
  13 static void __init wait_xfered(void)
  14 {
  15         unsigned int val;
  16
  17         /* wait for any previous char to be transmitted */
  18         do {
  19                 val = bcm_uart0_readl(UART_IR_REG);
  20                 if (val & UART_IR_STAT(UART_IR_TXEMPTY))
  21                         break;
  22         } while (1);
  23 }
  24
  25 void __init prom_putchar(char c)
  26 {
  27         wait_xfered();
  28         bcm_uart0_writel(c, UART_FIFO_REG);
  29         wait_xfered();
  30 }