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#include <asm/assembler.h>
14
15		.text
16
17/*
18 * Some debugging routines (useful if you've got MM problems and
19 * printk isn't working).  For DEBUGGING ONLY!!!  Do not leave
20 * references to these in a production kernel!
21 */
22
23#if defined(CONFIG_DEBUG_ICEDCC)
24		@@ debug using ARM EmbeddedICE DCC channel
25
26		.macro	addruart, rp, rv, tmp
27		.endm
28
29#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K) || defined(CONFIG_CPU_V7)
30
31		.macro	senduart, rd, rx
32		mcr	p14, 0, \rd, c0, c5, 0
33		.endm
34
35		.macro	busyuart, rd, rx
361001:
37		mrc	p14, 0, \rx, c0, c1, 0
38		tst	\rx, #0x20000000
39		beq	1001b
40		.endm
41
42		.macro	waituart, rd, rx
43		mov	\rd, #0x2000000
441001:
45		subs	\rd, \rd, #1
46		bmi	1002f
47		mrc	p14, 0, \rx, c0, c1, 0
48		tst	\rx, #0x20000000
49		bne	1001b
501002:
51		.endm
52
53#elif defined(CONFIG_CPU_XSCALE)
54
55		.macro	senduart, rd, rx
56		mcr	p14, 0, \rd, c8, c0, 0
57		.endm
58
59		.macro	busyuart, rd, rx
601001:
61		mrc	p14, 0, \rx, c14, c0, 0
62		tst	\rx, #0x10000000
63		beq	1001b
64		.endm
65
66		.macro	waituart, rd, rx
67		mov	\rd, #0x10000000
681001:
69		subs	\rd, \rd, #1
70		bmi	1002f
71		mrc	p14, 0, \rx, c14, c0, 0
72		tst	\rx, #0x10000000
73		bne	1001b
741002:
75		.endm
76
77#else
78
79		.macro	senduart, rd, rx
80		mcr	p14, 0, \rd, c1, c0, 0
81		.endm
82
83		.macro	busyuart, rd, rx
841001:
85		mrc	p14, 0, \rx, c0, c0, 0
86		tst	\rx, #2
87		beq	1001b
88
89		.endm
90
91		.macro	waituart, rd, rx
92		mov	\rd, #0x2000000
931001:
94		subs	\rd, \rd, #1
95		bmi	1002f
96		mrc	p14, 0, \rx, c0, c0, 0
97		tst	\rx, #2
98		bne	1001b
991002:
100		.endm
101
102#endif	/* CONFIG_CPU_V6 */
103
104#elif !defined(CONFIG_DEBUG_SEMIHOSTING)
105#include <mach/debug-macro.S>
106#endif	/* CONFIG_DEBUG_ICEDCC */
107
108#ifdef CONFIG_MMU
109		.macro	addruart_current, rx, tmp1, tmp2
110		addruart	\tmp1, \tmp2, \rx
111		mrc		p15, 0, \rx, c1, c0
112		tst		\rx, #1
113		moveq		\rx, \tmp1
114		movne		\rx, \tmp2
115		.endm
116
117#else /* !CONFIG_MMU */
118		.macro	addruart_current, rx, tmp1, tmp2
119		addruart	\rx, \tmp1
120		.endm
121
122#endif /* CONFIG_MMU */
123
124/*
125 * Useful debugging routines
126 */
127ENTRY(printhex8)
128		mov	r1, #8
129		b	printhex
130ENDPROC(printhex8)
131
132ENTRY(printhex4)
133		mov	r1, #4
134		b	printhex
135ENDPROC(printhex4)
136
137ENTRY(printhex2)
138		mov	r1, #2
139printhex:	adr	r2, hexbuf
140		add	r3, r2, r1
141		mov	r1, #0
142		strb	r1, [r3]
1431:		and	r1, r0, #15
144		mov	r0, r0, lsr #4
145		cmp	r1, #10
146		addlt	r1, r1, #'0'
147		addge	r1, r1, #'a' - 10
148		strb	r1, [r3, #-1]!
149		teq	r3, r2
150		bne	1b
151		mov	r0, r2
152		b	printascii
153ENDPROC(printhex2)
154
155hexbuf:		.space 16
156
157		.ltorg
158
159#ifndef CONFIG_DEBUG_SEMIHOSTING
160
161ENTRY(printascii)
162		addruart_current r3, r1, r2
163		b	2f
1641:		waituart r2, r3
165		senduart r1, r3
166		busyuart r2, r3
167		teq	r1, #'\n'
168		moveq	r1, #'\r'
169		beq	1b
1702:		teq	r0, #0
171		ldrneb	r1, [r0], #1
172		teqne	r1, #0
173		bne	1b
174		mov	pc, lr
175ENDPROC(printascii)
176
177ENTRY(printch)
178		addruart_current r3, r1, r2
179		mov	r1, r0
180		mov	r0, #0
181		b	1b
182ENDPROC(printch)
183
184#else
185
186ENTRY(printascii)
187		mov	r1, r0
188		mov	r0, #0x04		@ SYS_WRITE0
189	ARM(	svc	#0x123456	)
190	THUMB(	svc	#0xab		)
191		mov	pc, lr
192ENDPROC(printascii)
193
194ENTRY(printch)
195		adr	r1, hexbuf
196		strb	r0, [r1]
197		mov	r0, #0x03		@ SYS_WRITEC
198	ARM(	svc	#0x123456	)
199	THUMB(	svc	#0xab		)
200		mov	pc, lr
201ENDPROC(printch)
202
203#endif
204