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 31 static inline unsigned int serial_in(int offset) 32 { 33 return *((volatile IOTYPE *)PORT(offset)) & 0xFF; 34 } 35 36 static inline void serial_out(int offset, int value) 37 { 38 *((volatile IOTYPE *)PORT(offset)) = value & 0xFF; 39 } 40 41 void 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