Port-macppc archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: Booting original iMac



-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Hello,

On Mar 12, 2010, at 8:55 AM, John D. Baker wrote:

OK, not quite as straightforward as I thought.

On powerup, booting any NetBSD (4, 5, or -current) with machfb enabled
trashes the screen as described previously. It will do this every time
until...

If I boot MacOS X, any resolution, as long as the color depth is set to "thousands" (16-bit) (or less? I haven't tried.) and then simply restart (not shut down), subsequent booting of NetBSD with machfb enabled works
fine.

ofb or genfb work fine without such subterfugue.  genfb (5, -current)
clears the screen on attach as well, so I can't see any additional
previous kernel messages before the machine hangs.  I'll rebuild a
kernel with ofb instead of genfb (and disable machfb for the time
being) to try to get more visibility into the hangs.

Or try a -current kernel - it will replay the message buffer when a framebuffer driver attaches. So, it looks like your iMac wakes up in something else than 8 bit colour depth ( unlike all my machines ) and machfb always seems to assume 8 bit. That would at least explain the garbage you're seeing.
In order to confirm or contradict please do the following:
- - cold start the iMac and check what's in the graphics chip's depth property ( do 'dev screen', then '.properties' )
- - boot OSX, drop back to OF, check the depth property again
I might have to add code to either let machfb deal with colour depths other than 8 or make it switch to 8 if necessary.

have fun
Michael

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (Darwin)

iQEVAwUBS5qoVspnzkX8Yg2nAQJlAQgAnm/xiTss6CZlLSjI3EqWS6TSf7m6Nq2L
1mBU+7OQdQepB4L4YcIl+npDNNz7GK8krDQv+385mGCzeqP54IbABzJXnqrbU72v
FB1kUwFHAzBM0/nwAMyPAF6MEjNKqZ0Io5z/lTHbk9KlFmRw6+s/BUbE6zbPAHme
6Z13G/Q2+n4l5fyFbvo5bGr0hfaXcBiu69M/vs63E663aMZHvIcpvHfQzgv4ADAf
8klfSCavWH9BMLGVUWihPIIN9khtYtdGJWifXPHiNyfYK8MC4RM8ANEP8YJqtkJg
5s7rYBYC8M/jVofmXFh62hi5AwKGe/pVFk2FVic8IAe2uxMVbQwbgw==
=7hof
-----END PGP SIGNATURE-----


Home | Main Index | Thread Index | Old Index