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 46 static inline unsigned int serial_in(int offset) 47 { 48 return *((volatile IOTYPE *)PORT(offset)) & 0xFF; 49 } 50 51 static inline void serial_out(int offset, int value) 52 { 53 *((volatile IOTYPE *)PORT(offset)) = value & 0xFF; 54 } 55 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