1/* SPDX-License-Identifier: GPL-2.0+ */ 2/* 3 * linux/arch/arm/kernel/debug.S 4 * 5 * Copyright (C) 1994-1999 Russell King 6 * 7 * 32-bit debugging code 8 */ 9#include <linux/linkage.h> 10#include <asm/assembler.h> 11 12 .text 13 14/* 15 * Some debugging routines (useful if you've got MM problems and 16 * printk isn't working). For DEBUGGING ONLY!!! Do not leave 17 * references to these in a production kernel! 18 */ 19 20#if !defined(CONFIG_DEBUG_SEMIHOSTING) 21#include CONFIG_DEBUG_LL_INCLUDE 22#endif 23 24 .macro addruart_current, rx, tmp1, tmp2 25 addruart \rx, \tmp1, \tmp2 26 .endm 27 28/* 29 * Useful debugging routines 30 */ 31ENTRY(printhex8) 32 mov r1, #8 33 b printhex 34ENDPROC(printhex8) 35 36ENTRY(printhex4) 37 mov r1, #4 38 b printhex 39ENDPROC(printhex4) 40 41ENTRY(printhex2) 42 mov r1, #2 43printhex: adr r2, hexbuf 44 add r3, r2, r1 45 mov r1, #0 46 strb r1, [r3] 471: and r1, r0, #15 48 mov r0, r0, lsr #4 49 cmp r1, #10 50 addlt r1, r1, #'0' 51 addge r1, r1, #'a' - 10 52 strb r1, [r3, #-1]! 53 teq r3, r2 54 bne 1b 55 mov r0, r2 56 b printascii 57ENDPROC(printhex2) 58 59hexbuf: .space 16 60 61 .ltorg 62 63#ifndef CONFIG_DEBUG_SEMIHOSTING 64 65ENTRY(printascii) 66 addruart_current r3, r1, r2 67 b 2f 681: waituart r2, r3 69 senduart r1, r3 70 busyuart r2, r3 71 teq r1, #'\n' 72 moveq r1, #'\r' 73 beq 1b 742: teq r0, #0 75 ldrneb r1, [r0], #1 76 teqne r1, #0 77 bne 1b 78 mov pc, lr 79ENDPROC(printascii) 80 81ENTRY(printch) 82 addruart_current r3, r1, r2 83 mov r1, r0 84 mov r0, #0 85 b 1b 86ENDPROC(printch) 87 88#else 89 90ENTRY(printascii) 91 mov r1, r0 92 mov r0, #0x04 @ SYS_WRITE0 93 ARM( svc #0x123456 ) 94 THUMB( svc #0xab ) 95 mov pc, lr 96ENDPROC(printascii) 97 98ENTRY(printch) 99 adr r1, hexbuf 100 strb r0, [r1] 101 mov r0, #0x03 @ SYS_WRITEC 102 ARM( svc #0x123456 ) 103 THUMB( svc #0xab ) 104 mov pc, lr 105ENDPROC(printch) 106 107ENTRY(debug_ll_addr) 108 mov r2, #0 109 str r2, [r0] 110 str r2, [r1] 111 mov pc, lr 112ENDPROC(debug_ll_addr) 113 114#endif 115