epia800 direct vga working
steve at nexpath.com
Sun Sep 21 13:27:00 CEST 2003
SONE Takeshi wrote:
> On Sat, Sep 20, 2003 at 11:25:58PM -0700, Steve Gehlbach wrote:
>>Nathanael Noblet wrote:
>>>I don't need a framebuffer on boot, but once loaded would I be able to
>>>insmod the epiafb module and get that working?
>>More than likely, since a framebuffer driver made for epia vga must have
>>intimate knowledge of the chipset, so it should completely initialize it.
> Unfortunately it does not. Looks like we have to program some more
> VGA registers for framebuffer to function properly.
Hmmm... this is strange. Has anyone used HAVE_FRAMEBUFFER option
without VIDEO_CONSOLE and gotten that to work? The only difference is
the 0xFB chipset register, however, the setting I use matches the Award
setting when it boots. The HAVE_FRAMEBUFER sets the framebuffer size to
something different, but I don't think this is releveant, my setting
would be 8M but the frambuffer access bit (bit 3) is off, and the
address of the framebuffer is not set (bits 2-0 and reg 0xFA and others).
I suspect it has something to do with the graphics aperture settings
(GA). The GA relevant registers are 0x13 and 0x80-0x8B. You can try
putting in the settings at the bottom of afteram.inc (this file is not
used in my config), the CS_WRITE commands to 0x13, 0x84, 0x80, 0x88.
These match the Award settings, except for 0x84, which is 0 in Award
(256M aperture) rather than 0xc0 (64M aperture). I know that these
registers can cause hangs, though. I would try putting these in the
vgainit.inc file replacing the 0x88 setting where it says "turn off GA".
Which epiafb are you using? Maybe I can try it later this week, but I
am not a big user of framebuffers.
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