xref: /linux/arch/arm/kernel/debug.S (revision 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18)
1/*
2 *  linux/arch/arm/kernel/debug.S
3 *
4 *  Copyright (C) 1994-1999 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 *  32-bit debugging code
11 */
12#include <linux/linkage.h>
13
14		.text
15
16/*
17 * Some debugging routines (useful if you've got MM problems and
18 * printk isn't working).  For DEBUGGING ONLY!!!  Do not leave
19 * references to these in a production kernel!
20 */
21
22#if defined(CONFIG_DEBUG_ICEDCC)
23		@@ debug using ARM EmbeddedICE DCC channel
24
25#if defined(CONFIG_CPU_V6)
26
27		.macro	addruart, rx
28		.endm
29
30		.macro	senduart, rd, rx
31		mcr	p14, 0, \rd, c0, c5, 0
32		.endm
33
34		.macro	busyuart, rd, rx
351001:
36		mrc	p14, 0, \rx, c0, c1, 0
37		tst	\rx, #0x20000000
38		beq	1001b
39		.endm
40
41		.macro	waituart, rd, rx
42		mov	\rd, #0x2000000
431001:
44		subs	\rd, \rd, #1
45		bmi	1002f
46		mrc	p14, 0, \rx, c0, c1, 0
47		tst	\rx, #0x20000000
48		bne	1001b
491002:
50		.endm
51
52#else
53
54		.macro	addruart, rx
55		.endm
56
57		.macro	senduart, rd, rx
58		mcr	p14, 0, \rd, c1, c0, 0
59		.endm
60
61		.macro	busyuart, rd, rx
621001:
63		mrc	p14, 0, \rx, c0, c0, 0
64		tst	\rx, #2
65		beq	1001b
66
67		.endm
68
69		.macro	waituart, rd, rx
70		mov	\rd, #0x2000000
711001:
72		subs	\rd, \rd, #1
73		bmi	1002f
74		mrc	p14, 0, \rx, c0, c0, 0
75		tst	\rx, #2
76		bne	1001b
771002:
78		.endm
79
80#endif	/* CONFIG_CPU_V6 */
81
82#else
83#include <mach/debug-macro.S>
84#endif	/* CONFIG_DEBUG_ICEDCC */
85
86/*
87 * Useful debugging routines
88 */
89ENTRY(printhex8)
90		mov	r1, #8
91		b	printhex
92ENDPROC(printhex8)
93
94ENTRY(printhex4)
95		mov	r1, #4
96		b	printhex
97ENDPROC(printhex4)
98
99ENTRY(printhex2)
100		mov	r1, #2
101printhex:	adr	r2, hexbuf
102		add	r3, r2, r1
103		mov	r1, #0
104		strb	r1, [r3]
1051:		and	r1, r0, #15
106		mov	r0, r0, lsr #4
107		cmp	r1, #10
108		addlt	r1, r1, #'0'
109		addge	r1, r1, #'a' - 10
110		strb	r1, [r3, #-1]!
111		teq	r3, r2
112		bne	1b
113		mov	r0, r2
114		b	printascii
115ENDPROC(printhex2)
116
117		.ltorg
118
119ENTRY(printascii)
120		addruart r3
121		b	2f
1221:		waituart r2, r3
123		senduart r1, r3
124		busyuart r2, r3
125		teq	r1, #'\n'
126		moveq	r1, #'\r'
127		beq	1b
1282:		teq	r0, #0
129		ldrneb	r1, [r0], #1
130		teqne	r1, #0
131		bne	1b
132		mov	pc, lr
133ENDPROC(printascii)
134
135ENTRY(printch)
136		addruart r3
137		mov	r1, r0
138		mov	r0, #0
139		b	1b
140ENDPROC(printch)
141
142hexbuf:		.space 16
143