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