xref: /openbmc/linux/arch/mips/bcm63xx/early_printk.c (revision add48ba4)
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 <bcm63xx_io.h>
10 #include <linux/serial_bcm63xx.h>
11 #include <asm/setup.h>
12 
13 static void 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 prom_putchar(char c)
26 {
27 	wait_xfered();
28 	bcm_uart0_writel(c, UART_FIFO_REG);
29 	wait_xfered();
30 }
31