Re: 5121 cache handling.

On Mon, 2009-08-10 at 15:26 -0500, Scott Wood wrote:

Kenneth Johansson wrote:

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should not the framebuffer be marked as cache write through. that is the
W bit should be set in the tlb mapping. Why is this not done ? is that
feature also not working on 5121 ??

It probably would have been too slow.

how much slower would write through be ? I thought it was not that big
of a difference from copy back.

It's a big difference if you're writing out an entire cache line of data 
anyway, but because of write-through it goes out one word at a time 
without bursting.

-Scott

Yes the memory system would obviously get a higher load but do the CPU
actually see that? do it stall on the write ?