xref: /openbmc/linux/arch/arm/kernel/debug.S (revision b04b4f78)
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#elif defined(CONFIG_CPU_XSCALE)
53
54		.macro	addruart, rx
55		.endm
56
57		.macro	senduart, rd, rx
58		mcr	p14, 0, \rd, c8, c0, 0
59		.endm
60
61		.macro	busyuart, rd, rx
621001:
63		mrc	p14, 0, \rx, c14, c0, 0
64		tst	\rx, #0x10000000
65		beq	1001b
66		.endm
67
68		.macro	waituart, rd, rx
69		mov	\rd, #0x10000000
701001:
71		subs	\rd, \rd, #1
72		bmi	1002f
73		mrc	p14, 0, \rx, c14, c0, 0
74		tst	\rx, #0x10000000
75		bne	1001b
761002:
77		.endm
78
79#else
80
81		.macro	addruart, rx
82		.endm
83
84		.macro	senduart, rd, rx
85		mcr	p14, 0, \rd, c1, c0, 0
86		.endm
87
88		.macro	busyuart, rd, rx
891001:
90		mrc	p14, 0, \rx, c0, c0, 0
91		tst	\rx, #2
92		beq	1001b
93
94		.endm
95
96		.macro	waituart, rd, rx
97		mov	\rd, #0x2000000
981001:
99		subs	\rd, \rd, #1
100		bmi	1002f
101		mrc	p14, 0, \rx, c0, c0, 0
102		tst	\rx, #2
103		bne	1001b
1041002:
105		.endm
106
107#endif	/* CONFIG_CPU_V6 */
108
109#else
110#include <mach/debug-macro.S>
111#endif	/* CONFIG_DEBUG_ICEDCC */
112
113/*
114 * Useful debugging routines
115 */
116ENTRY(printhex8)
117		mov	r1, #8
118		b	printhex
119ENDPROC(printhex8)
120
121ENTRY(printhex4)
122		mov	r1, #4
123		b	printhex
124ENDPROC(printhex4)
125
126ENTRY(printhex2)
127		mov	r1, #2
128printhex:	adr	r2, hexbuf
129		add	r3, r2, r1
130		mov	r1, #0
131		strb	r1, [r3]
1321:		and	r1, r0, #15
133		mov	r0, r0, lsr #4
134		cmp	r1, #10
135		addlt	r1, r1, #'0'
136		addge	r1, r1, #'a' - 10
137		strb	r1, [r3, #-1]!
138		teq	r3, r2
139		bne	1b
140		mov	r0, r2
141		b	printascii
142ENDPROC(printhex2)
143
144		.ltorg
145
146ENTRY(printascii)
147		addruart r3
148		b	2f
1491:		waituart r2, r3
150		senduart r1, r3
151		busyuart r2, r3
152		teq	r1, #'\n'
153		moveq	r1, #'\r'
154		beq	1b
1552:		teq	r0, #0
156		ldrneb	r1, [r0], #1
157		teqne	r1, #0
158		bne	1b
159		mov	pc, lr
160ENDPROC(printascii)
161
162ENTRY(printch)
163		addruart r3
164		mov	r1, r0
165		mov	r0, #0
166		b	1b
167ENDPROC(printch)
168
169hexbuf:		.space 16
170