[PATCH V8 5/6] ACPI: Support the probing on the devices which apply indirect-IO
Rafael J. Wysocki
rjw at rjwysocki.net
Thu Mar 30 13:31:10 PDT 2017
On Thursday, March 30, 2017 11:26:58 PM zhichang.yuan wrote:
> On some platforms(such as Hip06/Hip07), the legacy ISA/LPC devices access I/O
> with some special host-local I/O ports known on x86. To access the I/O
> peripherals, an indirect-IO mechanism is introduced to mapped the host-local
> I/O to system logical/fake PIO similar the PCI MMIO on architectures where no
> separate I/O space exists. Just as PCI MMIO, the host I/O range should be
> registered before probing the downstream devices and set up the I/O mapping.
> But current ACPI bus probing doesn't support these indirect-IO hosts/devices.
>
> This patch introdueces a new ACPI handler for this device category. Through the
> handler attach callback, the indirect-IO hosts I/O registration is done and
> all peripherals' I/O resources are translated into logic/fake PIO before
> starting the enumeration.
Can you explain to me briefly what exactly this code is expected to be doing?
Thanks,
Rafael
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