Warner Losh writes:
> In message <XFMail.990707230857.Harald.Koerfgen@home.ivm.de> Harald Koerfgen
> : That's definitely true for R3k DECstations, and no, flushing the icache in
> : flush_tlb_page() does not help. I have added cacheflushing to all tlb
> : copy_page and even rw_swap_page_base() and swap_after_unlock_page() without
> : success.
> Don'y you want to flush the dcache as well? I think that you can run
> into problems when you have a dirty dcache and then dma into the pages
> that are dirty. Instant karma corruption, no? Or am I thinking of
> some other problem?
The R3000 has a write-through cache, so there cannot be dirty cache
lines, although you do have to flush the write buffers to be completely
correct (in the case of a DMA device writing to memory VERY quickly after
the register write which starts it up, on some hardware).