Hello,
After a couple of days of trying, we've finally successfully compiled a 'hello world' module and was able to load it under NiosII uClinux v1.3. Along the way we found 2 bugs that caused major problems:
1) Problem:
Stage 2 of the module compile doesn't work under Cygwin (Nios II SDK shell). The modpost.exe program is not correctly reading in the Module.symvers file since Module.symvers has DOS line endings.
Solution:
run dos2unix on Module.symvers (in the kernel build directory) before trying to compile your module. A better solution would be to fix modpost.exe (read_dump() function in scripts/mod/modpost.c) to handle DOS line endings.
2) Problem:
Module wouldn't load using insmod. Unresolved symbol error for printk.
After tracking this down we found that the problem was that the ksymtab table was not long-word aligned.
Solution:
Change /linux-2.6.x/arch/nios2nommu/kernel/vmlinux.lds.S to add
. = ALIGN(4);
before the ksymtab section. So it should look something like:
/* Kernel symbol table: Normal symbols */
. = ALIGN(4);
__start___ksymtab = .;
*(__ksymtab)
__stop___ksymtab = .;
These 2 changes fixed all of the problems we were seeing.
Hope this helps.
--
Terry Graessle
