jose manuel martin bravo

Question about Linux kernel debug

Discussion created by jose manuel martin bravo on May 18, 2006
Latest reply on May 18, 2006 by jose manuel martin bravo
Good morning:
i'm working on multiples boards simultaneously(an 860 and a 8272ADS).
Actually, i'm using u-boot to initialize boards. At this point, i start codewarrior 2.5.
Now, i speak only about MPC8272ADS. BSP installed is a linux-2.6.x kernel based. BSP id is CWB-MPC8272ADS-2-6-k.
In codewarrior, kernel is open using File->Open. Open file is vmlinux, non-compressed kernel image in elf format. Kernel was build with -g -ggdb at CFLAGS and -gdwarf2 at AFLAGS using PCS. I'm using an USBTap upgraded to version 1.6.
When kernel file is open, codewarrior shows an alert about hoy many files vmlinux reference.
Vmlinux.mcp window appear and all files contained are showed. Now, start to configure debugger.
Remote Debugging: USBTap with factory settings, no more options checked.
Debugger Settings: Stop on aplication launch -> program entry point. Other options at factory settings value.
Debugger Pic Settings: Alternate Load Address unchecked.
EPPC Debugger Settings: target processor 8272, target os Linux, Program
Download Options unckecked and verify memory writes unchecked.
EppcExceptions: all checked.
Linux kernel boot parameters: all unchecked.
Linux kernel debug settings: All ckeched, physical base address 0x00000000, virtual 0xc0000000, memory size 0x04000000.
Residual data unchecked.
With this configuration, i download kernel to target using u-boot tftpboot command. At this point, with cw, debug->attach to process is done.
Breakpoint window show an event point at start kernel. But cw hangs if i don't stablish a breakpoint at start_kernel too. If i stablish this breakpoint, repeated stops at start_kernel appear.
What's wrong?
Thanks in advice.