Re: [Qemu-devel] [RFC] qemu VGA endian swap low level drawing changes

[Gerd Hoffmann]

  Hi,

> Any objection ? I'll spend some time in the next few days getting myself
> a bit more familiar with that pixman stuff (I need to fix the ppc vector
> stuff for LE in there anyway) and come up with patches.

Sounds good.

Have a look at
https://www.kraxel.org/cgit/qemu/log/?h=rebase/console-wip

Has some console patches to make pixman the primary format specifier
(instead of pixman_format_code and PixelFormat living side-by-side).

That should make the control flow a bit easier to follow.  Also gives
some more flexibility to qemu_create_displaysurface_from() as it accepts
pixman format codes directly now.

/me goes continue look at pl110.  On a second look it isn't as easy as
it seemed initially.  But as it supports all sorts of funky formats it
serves well as example and also nicely shows what would be useful as
generic infrastructure ...

> Another step I hinted to earlier is how we do the actual endian
> transition. My idea is to add a new register to the BOCHS DISPI VBE
> list and bump the PCI revision ID to advertise its existence.

The dispi interface has a versioned id too (VBE_DISPI_IDx) which we
could use too.  Which makes sense IMO if we add the register to the
bochs dispi registers.

We could also place the register in pci config space, then indicate it
exists by either creating it a vendor pci capability or by pci revision.

cheers,
  Gerd