Linux Debug
From ArmadeusWiki
- Tips to do debug under linux **
Contents
Introduction
On this page, you will find usefull informations for debugging Armadeus under Linux
Testing your custom Linux kernel before flashing it
You can test a linux kernel you've generated without having to reflash your board and destroy your currently working image. Indeed Linux kernel images can be loaded and started from SDRAM with U-Boot:
BIOS> tftp 8000000 linux-kernel-2.6.16-arm.bin BIOS> bootm 8000000
Changing processor registers from Linux user space with imxregs
This tool allows you to access i.MXL registers from Linux userspace/console. This way you debug your driver or access i.MXL hardware functionnalities directly from Linux console.
- First, you have to enable this tool in Buildroot (package selection for target -> Hardware handling / blockdevices and filesystem maintenance -> imxregs):
$ make menuconfig
Once done, compile it:
$ make
The generated file is located in buildroot/build_arm/imxregs-1.0/. Now you can copy it on your target.
- To use it, you must clear PAR 1&2 registers (registers access rights) before launching Linux kernel, so in U-Boot type:
BIOS> mw.l 0x00200008 0 BIOS> mw.l 0x00210008 0
If you use it frequently, you can define a small script in U-Boot:
BIOS> setenv unlock_regs mw.l 0x00200008 0\; mw.l 0x00210008 0 BIOS> saveenv
and call it like that before launching your kernel:
BIOS> run unlock_regs
- Then in Linux console/terminal, launch imxregs like that:
# imxregs REGISTER_NAME (give it the register name as printed in iMX Ref Manual or just the begining of the name)
or
# imxregs (to dump all supported registers)
Examples:
- Show OCR1 registers of each GPIO Port:
# imxregs OCR1
- Write 0x00000123 to OCR1_D register:
# imxregs OCR1_D 123
Changing FPGA IP's registers from Linux user space with fpgaregs
see FPGA_register
