lpcware

I2C register access problem

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by goweol on Mon Mar 30 02:57:58 MST 2015
mmap /dev/mem and accessing the I2C data register gave me a fault.
Here is a linux command line log:

~ # md -w4 0x400a0000 4
Unhandled fault: external abort on non-linefetch (0x008) at 0x40156000
Bus error
~ # md -w4 0x400a0004 4
400a0004: 000022c0
~ # md -w4 0x400a0004 16
400a0004: 000022c0 00000000 0000033e 0000033e
~ # md -w4 0x400a8004 4
400a8004: 00002ac0
~ # md -w4 0x400a8000 4
Unhandled fault: external abort on non-linefetch (0x008) at 0x40132000
Bus error

As you can see, I cannot read '0x400a0000' (I2Cn rx data fifo register).
How I can access I2Cn rx/tx data FIFO register (as superuser)?
Does it possible?

NOTE: 'md' internally mmaps pagesize aligned address with multiple pagesize size (based on command line dump size) and dump the given address with given size..

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