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) 2011-2012 Gabor Juhos <juhosg@openwrt.org>
 7 */
 8
 9#include <linux/io.h>
10#include <linux/serial_reg.h>
11
12#include <asm/addrspace.h>
13
14#ifdef CONFIG_SOC_RT288X
15#define EARLY_UART_BASE         0x300c00
16#else
17#define EARLY_UART_BASE         0x10000c00
18#endif
19
20#define UART_REG_RX             0x00
21#define UART_REG_TX             0x04
22#define UART_REG_IER            0x08
23#define UART_REG_IIR            0x0c
24#define UART_REG_FCR            0x10
25#define UART_REG_LCR            0x14
26#define UART_REG_MCR            0x18
27#define UART_REG_LSR            0x1c
28
29static __iomem void *uart_membase = (__iomem void *) KSEG1ADDR(EARLY_UART_BASE);
30
31static inline void uart_w32(u32 val, unsigned reg)
32{
33	__raw_writel(val, uart_membase + reg);
34}
35
36static inline u32 uart_r32(unsigned reg)
37{
38	return __raw_readl(uart_membase + reg);
39}
40
41void prom_putchar(unsigned char ch)
42{
43	while ((uart_r32(UART_REG_LSR) & UART_LSR_THRE) == 0)
44		;
45	uart_w32(ch, UART_REG_TX);
46	while ((uart_r32(UART_REG_LSR) & UART_LSR_THRE) == 0)
47		;
48}