Re: [9front] core-i5(TypeSNB) and vesa mode

[kokamoto@hera.eonet.ne.jp]

After I touched with display codes, I realised I'm just familier
with the whole codes of igfx.c now.

I have a porpose to construct our strategy.

1) make separate of the hard tie connection of pipe(x) and transcoder
number (pipe(0) for display port A, pipe(1) for display port B etc).

2) as we can judge which display device is connected to a port by
examimming the 2 bit of dpctl(e0300, e1300, e2300 etc),
we can put the dpctl enable of that port.

3) we can do above both for pipe(0) and pipe(1).
Let's the pipe(0) alone for native vga mode, even if we use it 
or not.  Do the change to pipe(1) above, because we are now
dealing with only frame buffer, which is not so heavy.
In a future, if we deal with 3D movie etc, let's consider about it.

4) for G965, we use pipe(1) for high resolution mode, however,
we use pipe(0) for Sandy/Ivy Bridge.   I wondered why at the
beginning.   Now I understand the reason, however, to make it
harmony with the case of G965 etc is the second reason.

Kenji

PS. I maty be wrong, of course. If so please point it to me.