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Altera_Forum's avatar
Altera_Forum
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16 years ago

Linux with MMU on NEEK

Hi, all. I'm testing Linux MMU version, on my NEEK. http://www.nioswiki.com/linux It works fine and I can use "bash" shell. This is the evident proof that we are using the true 'fo...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

"virtually-indexed and physically-tagged" ???

How does this compare to ARM, that uses the cache and the MMU completely in the "wrong" order (strictly using physical addresses in the cache). Because of that, ARM-Linux needs to flush the cache completely with any task-switch. That is why for ARM systems with many task switches, not using the MMU is recommended.

I sincerely hope that such a drastic method is not necessary with NIOS !

Happily, I myself am planing a heavily multithreaded system, so not that many MMU reprogramming (and cache invalidating) as with a heavily multitasking system. Same is only possible with MMU, as the non-MMU-compiler does not support TLS, which is essential to do decent multithreaded applications.

-Michael