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