Re: [Qemu-devel] [SeaBIOS] [Seabios] [PATCH 0/6] 64bit PCI BARs allocations (take 2)

[Gerd Hoffmann]

  Hi,

> Hrmm.  By my count, this would be the third "rewrite" of the PCI bar
> initialization in the last 14 months.

Indeed.

> Given the churn in this area, I don't want to commit patches that do
> wholesale code replacement.  I'd prefer to see each patch
> independently add some functionality and perform its related cleanup.

Hardly doable, the algorithms are very different.

> Also, since Gerd has some patches pending in this area, we should
> figure out which direction makes sense.  Can you explain on how this
> 64bit support is different from the support proposed by Gerd?

My code keeps all state needed to do the pci bar allocation in the
pci_bus struct.  It counts how many bars of each type+size it has, then
uses this for the allocation.  It doesn't need per-device state.  The
logic is a bit twisted because of that.  Main reason for this is that I
wrote it before "struct pci_device" showed up in seabios (although the
merge was afterwards).

Alexey's code takes a very different route:  It uses pci_device data
structure instead and organizes the pci bars in per-region lists.  It
makes sense to do that, I think that version is easier to understand
when you look at it the first time.

Both approaches will work fine in the end.  I don't care much, I just
want something that works.  It's probably a bit risky to merge Alexey's
version before the planned mid-march release.

cheers,
  Gerd