[Intel-gfx] Dear Intel: please document SDVO LVDS option block
Keith Packard
keithp at keithp.com
Mon Nov 28 18:28:35 CET 2011
On Wed, 26 Oct 2011 10:53:11 -0400, Adam Jackson <ajax at redhat.com> wrote:
> On Wed, 2011-10-19 at 10:28 -0400, Adam Jackson wrote:
>
> > I assume the SDVO LVDS options block in the VBT would tell us what bits
> > are correct to program here, but intel_bios.h documents only the layout
> > of that structure, not its content. Or, we can hope that the SDVO card
> > set it up correctly for us (hah).
> >
> > Intel people, care to shed some light here?
>
> Just re-raising this. I suspect we can't support SDVO LVDS correctly
> without knowing more here. In particular:
>
> - what "panel type" means in struct bdb_sdvo_lvds_options
Which of the four panels in the SDVO info is actually connected.
> - what the "misc bits" mean in same
LVDS_Misc_Bits_1
Bits [7:6] = Reserved
Bit 5 = Dither
= 0, off
= 1, on
Bit 4 = Panel Fitting
= 0, Disabled
= 1, Enabled
Bit 3 = Panel EDID support - Reserved
= 0, Disabled
= 1, Enabled
Bit 2 - 0 = Panel protection
Bit 2 - Monitor Pixel Clk (0 = off, 1 = on)
Bit 1 - Monitor VSync (0 = off, 1 = on)
Bit 0 - Monitor HSync (0 = off, 1 = on)
LVDS_Misc_Bits_2
Bit 7 = LVDS SSC Enabled
= 0, Disabled
= 1, Enabled
Bit6 = Disable SSC in Dual Twin Display
= 0, Not disabled
= 1, Disabled
Bits[5:4] = LVDS Channel
= 02-03, Reserved
= 01, Dual Channel
= 00, Single Channel
Bits[3:2] = Panel Connector
= 01, OpenLDI
= 00, SPGW
Bits[1:0] = Panel color depth
= 02-03, Reserved
= 01, 24-bit Color depth
= 00, 18-bit Color depth
LVDS_Misc_Bits_3
Bits [7:4] = Reserved
Bit 3 = Panel #4
= 0, Single Channel
= 1, Dual Channel
Bit 2 = Panel #3
= 0, Single Channel
= 1, Dual Channel
Bit 1 = Panel #2
= 0, Single Channel
= 1, Dual Channel
Bit 0 = Panel #1
= 0, Single Channel
= 1, Dual Channel
> - whether the BIOS AIM code can be relied on to have set
> depth/type/channel correctly or if that's the driver's job
That, I'm afraid, I haven't a clue about -- the BIOS does try to light
up every display, but it can run out of resources just like Linux, and I
don't know what happens when there's not enough pipes to go around.
--
keith.packard at intel.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 827 bytes
Desc: not available
URL: <http://lists.freedesktop.org/archives/intel-gfx/attachments/20111128/0c287c6c/attachment.sig>
More information about the Intel-gfx
mailing list