1// SPDX-License-Identifier: GPL-2.0
2/*
3 * 16550 compatible uart based serial debug support for zboot
4 */
5
6#include <linux/types.h>
7#include <linux/serial_reg.h>
8
9#include <asm/addrspace.h>
10
11#include "decompress.h"
12
13#if defined(CONFIG_MACH_LOONGSON64) || defined(CONFIG_MIPS_MALTA)
14#define UART_BASE 0x1fd003f8
15#define PORT(offset) (CKSEG1ADDR(UART_BASE) + (offset))
16#endif
17
18#ifdef CONFIG_MACH_INGENIC
19#define INGENIC_UART_BASE_ADDR	(0x10030000 + 0x1000 * CONFIG_ZBOOT_INGENIC_UART)
20#define PORT(offset) (CKSEG1ADDR(INGENIC_UART_BASE_ADDR) + (4 * offset))
21#endif
22
23#ifndef IOTYPE
24#define IOTYPE char
25#endif
26
27#ifndef PORT
28#error please define the serial port address for your own machine
29#endif
30
31static inline unsigned int serial_in(int offset)
32{
33	return *((volatile IOTYPE *)PORT(offset)) & 0xFF;
34}
35
36static inline void serial_out(int offset, int value)
37{
38	*((volatile IOTYPE *)PORT(offset)) = value & 0xFF;
39}
40
41void putc(char c)
42{
43	int timeout = 1000000;
44
45	while (((serial_in(UART_LSR) & UART_LSR_THRE) == 0) && (timeout-- > 0))
46		;
47
48	serial_out(UART_TX, c);
49}
50