xref: /openbmc/linux/arch/mips/bcm63xx/early_printk.c (revision 4f6cce39)
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 
12 static void wait_xfered(void)
13 {
14 	unsigned int val;
15 
16 	/* wait for any previous char to be transmitted */
17 	do {
18 		val = bcm_uart0_readl(UART_IR_REG);
19 		if (val & UART_IR_STAT(UART_IR_TXEMPTY))
20 			break;
21 	} while (1);
22 }
23 
24 void prom_putchar(char c)
25 {
26 	wait_xfered();
27 	bcm_uart0_writel(c, UART_FIFO_REG);
28 	wait_xfered();
29 }
30