Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

Porting non-mmu code to MMU -- MMU memcpy SEGV

Thanks in Advance. With the non-mmu nios2 our design defined sdram regions that we utilized for buffers in our custom device driver. **** device driver sharedMem = kmalloc( SHARED_MEMSIZE...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

Thanks for pointing me to some drivers to study. I really don't need to be portable, but always try to be.

I have been working on adding the "mmap" function to my device driver. Was hoping to keep the "kmalloc" to get the memory but was getting an error in the drivers "mmap." I was getting interrupted a lot and had only skimmed Rubini book to understand things better.

Tomorrow I should have uninterrupted time. Going to start by reading Rubini.

I wasn't planning on using the device file (from reading it didnt seem necessary).

My other issue that I see I'll need to handle is the fact that I have 3 separate memory blocks to handle, so my mmap will need to take care of that by using the vm_start.