arch/arm/kernel/debug.S

   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
  36 1001:
  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
  44 1001:
  45                 subs    \rd, \rd, #1
  46                 bmi     1002f
  47                 mrc     p14, 0, \rx, c0, c1, 0
  48                 tst     \rx, #0x20000000
  49                 bne     1001b
  50 1002:
  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
  60 1001:
  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
  68 1001:
  69                 subs    \rd, \rd, #1
  70                 bmi     1002f
  71                 mrc     p14, 0, \rx, c14, c0, 0
  72                 tst     \rx, #0x10000000
  73                 bne     1001b
  74 1002:
  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
  84 1001:
  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
  93 1001:
  94                 subs    \rd, \rd, #1
  95                 bmi     1002f
  96                 mrc     p14, 0, \rx, c0, c0, 0
  97                 tst     \rx, #2
  98                 bne     1001b
  99 1002:
 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  */
 127 ENTRY(printhex8)
 128                 mov     r1, #8
 129                 b       printhex
 130 ENDPROC(printhex8)
 131
 132 ENTRY(printhex4)
 133                 mov     r1, #4
 134                 b       printhex
 135 ENDPROC(printhex4)
 136
 137 ENTRY(printhex2)
 138                 mov     r1, #2
 139 printhex:       adr     r2, hexbuf
 140                 add     r3, r2, r1
 141                 mov     r1, #0
 142                 strb    r1, [r3]
 143 1:              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
 153 ENDPROC(printhex2)
 154
 155 hexbuf:         .space 16
 156
 157                 .ltorg
 158
 159 #ifndef CONFIG_DEBUG_SEMIHOSTING
 160
 161 ENTRY(printascii)
 162                 addruart_current r3, r1, r2
 163                 b       2f
 164 1:              waituart r2, r3
 165                 senduart r1, r3
 166                 busyuart r2, r3
 167                 teq     r1, #'\n'
 168                 moveq   r1, #'\r'
 169                 beq     1b
 170 2:              teq     r0, #0
 171                 ldrneb  r1, [r0], #1
 172                 teqne   r1, #0
 173                 bne     1b
 174                 mov     pc, lr
 175 ENDPROC(printascii)
 176
 177 ENTRY(printch)
 178                 addruart_current r3, r1, r2
 179                 mov     r1, r0
 180                 mov     r0, #0
 181                 b       1b
 182 ENDPROC(printch)
 183
 184 #else
 185
 186 ENTRY(printascii)
 187                 mov     r1, r0
 188                 mov     r0, #0x04               @ SYS_WRITE0
 189         ARM(    svc     #0x123456       )
 190         THUMB(  svc     #0xab           )
 191                 mov     pc, lr
 192 ENDPROC(printascii)
 193
 194 ENTRY(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
 201 ENDPROC(printch)
 202
 203 #endif