Re: PATCH: improved processor config for G3s

Gabriel Paubert wrote:

So you need at least 3 writes, or to have one store buffer busy with a
previous write, to trigger the store gathering mechanism. This makes it
impossible to predict whether it will be used or not, and IMO not worth
the potential trouble since it will actually happen quite infrequently.

This condition should be satisfied by memcpy_toio(). It won't be
satisfied by fb_memmove(), which is the function that makes large
virtual consoles on PowerPC so slow.

It might be more interesting to try an implementation of memcpy_toio()
using the DMA engines of the 106/7.

- Adrian Cox, AG Electronics

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