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 #if defined(CONFIG_MACH_LOONGSON64) || defined(CONFIG_MIPS_MALTA)
12 #define UART_BASE 0x1fd003f8
13 #define PORT(offset) (CKSEG1ADDR(UART_BASE) + (offset))
14 #endif
15 
16 #ifdef CONFIG_AR7
17 #include <ar7.h>
18 #define PORT(offset) (CKSEG1ADDR(AR7_REGS_UART0) + (4 * offset))
19 #endif
20 
21 #ifdef CONFIG_MACH_INGENIC
22 #define INGENIC_UART0_BASE_ADDR	0x10030000
23 #define PORT(offset) (CKSEG1ADDR(INGENIC_UART0_BASE_ADDR) + (4 * offset))
24 #endif
25 
26 #ifdef CONFIG_CPU_XLR
27 #define UART0_BASE  0x1EF14000
28 #define PORT(offset) (CKSEG1ADDR(UART0_BASE) + (4 * offset))
29 #define IOTYPE unsigned int
30 #endif
31 
32 #ifdef CONFIG_CPU_XLP
33 #define UART0_BASE  0x18030100
34 #define PORT(offset) (CKSEG1ADDR(UART0_BASE) + (4 * offset))
35 #define IOTYPE unsigned int
36 #endif
37 
38 #ifndef IOTYPE
39 #define IOTYPE char
40 #endif
41 
42 #ifndef PORT
43 #error please define the serial port address for your own machine
44 #endif
45 
serial_in(int offset)46 static inline unsigned int serial_in(int offset)
47 {
48 	return *((volatile IOTYPE *)PORT(offset)) & 0xFF;
49 }
50 
serial_out(int offset,int value)51 static inline void serial_out(int offset, int value)
52 {
53 	*((volatile IOTYPE *)PORT(offset)) = value & 0xFF;
54 }
55 
putc(char c)56 void putc(char c)
57 {
58 	int timeout = 1000000;
59 
60 	while (((serial_in(UART_LSR) & UART_LSR_THRE) == 0) && (timeout-- > 0))
61 		;
62 
63 	serial_out(UART_TX, c);
64 }
65