In some devices, there may be multiple isa bridges available from different
sources. Therefore, we allow multiple lpc devices to be generated so that
pcie bus won't show "none" anymore.
For example, in my AMD based Framework Laptop, there are two such
bridges. One is acpi hinted, another is from pcie.
Details
- Reviewers
imp markj lwhsu - Commits
- rGf32ffd11b547: isa_common: allow multiple device instances
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- rG FreeBSD src repository
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I think nobody cares about isa bus stuff.
Also, no modern hardware attaches to isa bridge actually.
But it is really annoying for me to see "none" in pciconf -lv.
@jhb do you think that it is fine? Since you know much about pcie, and isa is the predecessor of pci(e).
I suspect this is fine. ISA is all the on boatd IO that's ioport mapped that's not part of pci. It most likely is lpc based and the ACPI enumeration of that jardware should hang off this bus, not the acpi bus for the software model. But practically, this is easier and there's not enough difference to mater.
Thanks! Warner. I also see the PCI-ISA bridge in QEMU and ISA is actually occupied by pci bus in that case.
I have a question, I see the isa_dma stuff. Wouldn't it mean that ISA can also alloc memory resources? Yes, again, nobody uses it anymore.
These are just some curiosities from a guy who saw that ACPI + PCIe have dominated the x86 world when he had the intellect to play with computers.
I think this is fine. Let's add a longer MFC time (say 2 weeks) to ensure there is no regression.