xref: /openbmc/linux/arch/arm/kernel/debug.S (revision e9e8bcb8)
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		.macro	addruart, rp, rv
26		.endm
27
28#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K) || defined(CONFIG_CPU_V7)
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#elif defined(CONFIG_CPU_XSCALE)
53
54		.macro	senduart, rd, rx
55		mcr	p14, 0, \rd, c8, c0, 0
56		.endm
57
58		.macro	busyuart, rd, rx
591001:
60		mrc	p14, 0, \rx, c14, c0, 0
61		tst	\rx, #0x10000000
62		beq	1001b
63		.endm
64
65		.macro	waituart, rd, rx
66		mov	\rd, #0x10000000
671001:
68		subs	\rd, \rd, #1
69		bmi	1002f
70		mrc	p14, 0, \rx, c14, c0, 0
71		tst	\rx, #0x10000000
72		bne	1001b
731002:
74		.endm
75
76#else
77
78		.macro	senduart, rd, rx
79		mcr	p14, 0, \rd, c1, c0, 0
80		.endm
81
82		.macro	busyuart, rd, rx
831001:
84		mrc	p14, 0, \rx, c0, c0, 0
85		tst	\rx, #2
86		beq	1001b
87
88		.endm
89
90		.macro	waituart, rd, rx
91		mov	\rd, #0x2000000
921001:
93		subs	\rd, \rd, #1
94		bmi	1002f
95		mrc	p14, 0, \rx, c0, c0, 0
96		tst	\rx, #2
97		bne	1001b
981002:
99		.endm
100
101#endif	/* CONFIG_CPU_V6 */
102
103#else
104#include <mach/debug-macro.S>
105#endif	/* CONFIG_DEBUG_ICEDCC */
106
107#ifdef CONFIG_MMU
108		.macro	addruart_current, rx, tmp1, tmp2
109		addruart	\tmp1, \tmp2
110		mrc		p15, 0, \rx, c1, c0
111		tst		\rx, #1
112		moveq		\rx, \tmp1
113		movne		\rx, \tmp2
114		.endm
115
116#else /* !CONFIG_MMU */
117		.macro	addruart_current, rx, tmp1, tmp2
118		addruart	\rx, \tmp1
119		.endm
120
121#endif /* CONFIG_MMU */
122
123/*
124 * Useful debugging routines
125 */
126ENTRY(printhex8)
127		mov	r1, #8
128		b	printhex
129ENDPROC(printhex8)
130
131ENTRY(printhex4)
132		mov	r1, #4
133		b	printhex
134ENDPROC(printhex4)
135
136ENTRY(printhex2)
137		mov	r1, #2
138printhex:	adr	r2, hexbuf
139		add	r3, r2, r1
140		mov	r1, #0
141		strb	r1, [r3]
1421:		and	r1, r0, #15
143		mov	r0, r0, lsr #4
144		cmp	r1, #10
145		addlt	r1, r1, #'0'
146		addge	r1, r1, #'a' - 10
147		strb	r1, [r3, #-1]!
148		teq	r3, r2
149		bne	1b
150		mov	r0, r2
151		b	printascii
152ENDPROC(printhex2)
153
154		.ltorg
155
156ENTRY(printascii)
157		addruart_current r3, r1, r2
158		b	2f
1591:		waituart r2, r3
160		senduart r1, r3
161		busyuart r2, r3
162		teq	r1, #'\n'
163		moveq	r1, #'\r'
164		beq	1b
1652:		teq	r0, #0
166		ldrneb	r1, [r0], #1
167		teqne	r1, #0
168		bne	1b
169		mov	pc, lr
170ENDPROC(printascii)
171
172ENTRY(printch)
173		addruart_current r3, r1, r2
174		mov	r1, r0
175		mov	r0, #0
176		b	1b
177ENDPROC(printch)
178
179hexbuf:		.space 16
180