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
  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)
  29
  30                 .macro  senduart, rd, rx
  31                 mcr     p14, 0, \rd, c0, c5, 0
  32                 .endm
  33
  34                 .macro  busyuart, rd, rx
  35 1001:
  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
  43 1001:
  44                 subs    \rd, \rd, #1
  45                 bmi     1002f
  46                 mrc     p14, 0, \rx, c0, c1, 0
  47                 tst     \rx, #0x20000000
  48                 bne     1001b
  49 1002:
  50                 .endm
  51
  52 #elif defined(CONFIG_CPU_V7)
  53
  54                 .macro  senduart, rd, rx
  55                 mcr     p14, 0, \rd, c0, c5, 0
  56                 .endm
  57
  58                 .macro  busyuart, rd, rx
  59 busy:           mrc     p14, 0, pc, c0, c1, 0
  60                 bcs     busy
  61                 .endm
  62
  63                 .macro  waituart, rd, rx
  64 wait:           mrc     p14, 0, pc, c0, c1, 0
  65                 bcs     wait
  66
  67                 .endm
  68
  69 #elif defined(CONFIG_CPU_XSCALE)
  70
  71                 .macro  senduart, rd, rx
  72                 mcr     p14, 0, \rd, c8, c0, 0
  73                 .endm
  74
  75                 .macro  busyuart, rd, rx
  76 1001:
  77                 mrc     p14, 0, \rx, c14, c0, 0
  78                 tst     \rx, #0x10000000
  79                 beq     1001b
  80                 .endm
  81
  82                 .macro  waituart, rd, rx
  83                 mov     \rd, #0x10000000
  84 1001:
  85                 subs    \rd, \rd, #1
  86                 bmi     1002f
  87                 mrc     p14, 0, \rx, c14, c0, 0
  88                 tst     \rx, #0x10000000
  89                 bne     1001b
  90 1002:
  91                 .endm
  92
  93 #else
  94
  95                 .macro  senduart, rd, rx
  96                 mcr     p14, 0, \rd, c1, c0, 0
  97                 .endm
  98
  99                 .macro  busyuart, rd, rx
 100 1001:
 101                 mrc     p14, 0, \rx, c0, c0, 0
 102                 tst     \rx, #2
 103                 beq     1001b
 104
 105                 .endm
 106
 107                 .macro  waituart, rd, rx
 108                 mov     \rd, #0x2000000
 109 1001:
 110                 subs    \rd, \rd, #1
 111                 bmi     1002f
 112                 mrc     p14, 0, \rx, c0, c0, 0
 113                 tst     \rx, #2
 114                 bne     1001b
 115 1002:
 116                 .endm
 117
 118 #endif  /* CONFIG_CPU_V6 */
 119
 120 #else
 121 #include <mach/debug-macro.S>
 122 #endif  /* CONFIG_DEBUG_ICEDCC */
 123
 124 #ifdef CONFIG_MMU
 125                 .macro  addruart_current, rx, tmp1, tmp2
 126                 addruart        \tmp1, \tmp2
 127                 mrc             p15, 0, \rx, c1, c0
 128                 tst             \rx, #1
 129                 moveq           \rx, \tmp1
 130                 movne           \rx, \tmp2
 131                 .endm
 132
 133 #else /* !CONFIG_MMU */
 134                 .macro  addruart_current, rx, tmp1, tmp2
 135                 addruart        \rx, \tmp1
 136                 .endm
 137
 138 #endif /* CONFIG_MMU */
 139
 140 /*
 141  * Useful debugging routines
 142  */
 143 ENTRY(printhex8)
 144                 mov     r1, #8
 145                 b       printhex
 146 ENDPROC(printhex8)
 147
 148 ENTRY(printhex4)
 149                 mov     r1, #4
 150                 b       printhex
 151 ENDPROC(printhex4)
 152
 153 ENTRY(printhex2)
 154                 mov     r1, #2
 155 printhex:       adr     r2, hexbuf
 156                 add     r3, r2, r1
 157                 mov     r1, #0
 158                 strb    r1, [r3]
 159 1:              and     r1, r0, #15
 160                 mov     r0, r0, lsr #4
 161                 cmp     r1, #10
 162                 addlt   r1, r1, #'0'
 163                 addge   r1, r1, #'a' - 10
 164                 strb    r1, [r3, #-1]!
 165                 teq     r3, r2
 166                 bne     1b
 167                 mov     r0, r2
 168                 b       printascii
 169 ENDPROC(printhex2)
 170
 171                 .ltorg
 172
 173 ENTRY(printascii)
 174                 addruart_current r3, r1, r2
 175                 b       2f
 176 1:              waituart r2, r3
 177                 senduart r1, r3
 178                 busyuart r2, r3
 179                 teq     r1, #'\n'
 180                 moveq   r1, #'\r'
 181                 beq     1b
 182 2:              teq     r0, #0
 183                 ldrneb  r1, [r0], #1
 184                 teqne   r1, #0
 185                 bne     1b
 186                 mov     pc, lr
 187 ENDPROC(printascii)
 188
 189 ENTRY(printch)
 190                 addruart_current r3, r1, r2
 191                 mov     r1, r0
 192                 mov     r0, #0
 193                 b       1b
 194 ENDPROC(printch)
 195
 196 hexbuf:         .space 16