projects/linux·blob master · refs

161 lines · 2.6 KiB

1/* SPDX-License-Identifier: GPL-2.0-only */
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#ifdef CONFIG_MMU
25 .macro addruart_current, rx, tmp1, tmp2
26 addruart \tmp1, \tmp2, \rx
27 mrc p15, 0, \rx, c1, c0
28 tst \rx, #1
29 moveq \rx, \tmp1
30 movne \rx, \tmp2
31 .endm
32
33#else /* !CONFIG_MMU */
34 .macro addruart_current, rx, tmp1, tmp2
35 addruart \rx, \tmp1, \tmp2
36 .endm
37
38#endif /* CONFIG_MMU */
39
40/*
41 * Useful debugging routines
42 */
43ENTRY(printhex8)
44 mov r1, #8
45 b printhex
46ENDPROC(printhex8)
47
48ENTRY(printhex4)
49 mov r1, #4
50 b printhex
51ENDPROC(printhex4)
52
53ENTRY(printhex2)
54 mov r1, #2
55printhex: adr r2, hexbuf_rel
56 ldr r3, [r2]
57 add r2, r2, r3
58 add r3, r2, r1
59 mov r1, #0
60 strb r1, [r3]
611: and r1, r0, #15
62 mov r0, r0, lsr #4
63 cmp r1, #10
64 addlt r1, r1, #'0'
65 addge r1, r1, #'a' - 10
66 strb r1, [r3, #-1]!
67 teq r3, r2
68 bne 1b
69 mov r0, r2
70 b printascii
71ENDPROC(printhex2)
72
73 .pushsection .bss
74hexbuf_addr: .space 16
75 .popsection
76 .align
77hexbuf_rel: .long hexbuf_addr - .
78
79 .ltorg
80
81#ifndef CONFIG_DEBUG_SEMIHOSTING
82
83ENTRY(printascii)
84 addruart_current r3, r1, r2
851: teq r0, #0
86 ldrbne r1, [r0], #1
87 teqne r1, #0
88 reteq lr
892: teq r1, #'\n'
90 bne 3f
91 mov r1, #'\r'
92#ifdef CONFIG_DEBUG_UART_FLOW_CONTROL
93 waituartcts r2, r3
94#endif
95 waituarttxrdy r2, r3
96 senduart r1, r3
97 busyuart r2, r3
98 mov r1, #'\n'
993:
100#ifdef CONFIG_DEBUG_UART_FLOW_CONTROL
101 waituartcts r2, r3
102#endif
103 waituarttxrdy r2, r3
104 senduart r1, r3
105 busyuart r2, r3
106 b 1b
107ENDPROC(printascii)
108
109ENTRY(printch)
110 addruart_current r3, r1, r2
111 mov r1, r0
112 mov r0, #0
113 b 2b
114ENDPROC(printch)
115
116#ifdef CONFIG_MMU
117ENTRY(debug_ll_addr)
118 addruart r2, r3, ip
119 str r2, [r0]
120 str r3, [r1]
121 ret lr
122ENDPROC(debug_ll_addr)
123#endif
124
125#else
126
127ENTRY(printascii)
128 mov r1, r0
129 mov r0, #0x04 @ SYS_WRITE0
130 ARM( svc #0x123456 )
131#ifdef CONFIG_CPU_V7M
132 THUMB( bkpt #0xab )
133#else
134 THUMB( svc #0xab )
135#endif
136 ret lr
137ENDPROC(printascii)
138
139ENTRY(printch)
140 adr r1, hexbuf_rel
141 ldr r2, [r1]
142 add r1, r1, r2
143 strb r0, [r1]
144 mov r0, #0x03 @ SYS_WRITEC
145 ARM( svc #0x123456 )
146#ifdef CONFIG_CPU_V7M
147 THUMB( bkpt #0xab )
148#else
149 THUMB( svc #0xab )
150#endif
151 ret lr
152ENDPROC(printch)
153
154ENTRY(debug_ll_addr)
155 mov r2, #0
156 str r2, [r0]
157 str r2, [r1]
158 ret lr
159ENDPROC(debug_ll_addr)
160
161#endif