求助：在pxa255板子上修改内核频率时的错误

elda

我使用PXA255处理器作相应开发，尝试动态调频，在读取cpu频率时，首先要读取其CCCR寄存器进行频率计算，0x41300000为CCCR地址，我用下面的汇编读取：
asm("ldr r0,=0x41300000\n"
        "ldr r1,[r0] \n"
        "str r1, %0" : "=m"(mycccr));
模块中一加入这些汇编，就出现错误，错误提示为：
ffc0: c0230c4c c0200c38 c01effe4 c01effd8 c0065030 c0066420 c01efffc c01effe8
ffe0: c000887c c006500c c020104c c0230c4c 00000000 c01f0000 c0008080 c0008788
Backtrace:
Function entered at [<c6930060>] from [<c693031c>]
Function entered at [<c6930270>] from [<c007bb7c>]
Function entered at [<c007b908>] from [<c0077bb4>]
Function entered at [<c0077b7c>] from [<c0077a6c>]
r4 = C0208700
Function entered at [<c00779f4>] from [<c0077730>]
r7 = C02086E0  r6 = FFFFFFFE  r5 = C01F00C0  r4 = 00000001
Function entered at [<c00776b4>] from [<c0065fd4>]
r8 = C01FFF18  r7 = C0200158  r6 = 00000000  r5 = 00000012
r4 = 00000000
Function entered at [<c0065eac>] from [<c0065300>]
Function entered at [<c0066b58>] from [<c0066474>]
r4 = C01EE000
Function entered at [<c0066414>] from [<c0065030>]
r6 = C0200C38  r5 = C0230C4C  r4 = 00004000
Function entered at [<c0065000>] from [<c000887c>]
Function entered at [<c000877c>] from [<c0008080>]
Code: eb0001d7 e59f0140 eb0001d5 e59f0468 (e5901000)
Kernel panic: Aiee, killing interrupt handler!
In interrupt handler - not syncing

求助！！！！
谢谢。