On Wednesday, March 14, 2018 7:15:57 PM CET John Garry wrote: > Through the logical PIO framework systems which otherwise have > no IO space access to legacy ISA/LPC devices may access these > devices through so-called "indirect IO" method. In this, IO > space accesses for non-PCI hosts are redirected to a host > LLDD to manually generate the IO space (bus) accesses. Hosts > are able to register a region in logical PIO space to map to > its bus address range. > > Indirect IO child devices have an associated host-specific bus > address. Special translation is required to map between > a logical PIO address for a device and it's host bus address. > > Since in the ACPI tables the child device IO resources would > be the host-specific values, it is required the ACPI scan code > should not enumerate these devices, and that this should be > the responsibility of the host driver so that it can "fixup" > the resources so that they map to the appropriate logical PIO > addresses. > > To avoid enumerating these child devices, we add a check from > acpi_device_enumeration_by_parent() as to whether the parent > for a device is a member of a known list of "indirect IO" hosts. > For now, the HiSilicon LPC host controller ID is added. > > Signed-off-by: John Garry <[email protected]> > Acked-by: Rafael J. Wysocki <[email protected]>
You have my ACK here already. Since I've ACKed the [7/10] too, I don't think there's anything more I can do about this series and I'm assuming that it will be routed through other trees. Thanks! > Reviewed-by: Andy Shevchenko <[email protected]> > Tested-by: dann frazier <[email protected]> > --- > drivers/acpi/scan.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index f9e7904..a4cbf3e 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -1524,11 +1524,25 @@ static int acpi_check_serial_bus_slave(struct > acpi_resource *ares, void *data) > return -1; > } > > +static bool acpi_is_indirect_io_slave(struct acpi_device *device) > +{ > + struct acpi_device *parent = device->parent; > + const struct acpi_device_id indirect_io_hosts[] = { > + {"HISI0191", 0}, > + {} > + }; > + > + return parent && !acpi_match_device_ids(parent, indirect_io_hosts); > +} > + > static bool acpi_device_enumeration_by_parent(struct acpi_device *device) > { > struct list_head resource_list; > bool is_serial_bus_slave = false; > > + if (acpi_is_indirect_io_slave(device)) > + return true; > + > /* Macs use device properties in lieu of _CRS resources */ > if (x86_apple_machine && > (fwnode_property_present(&device->fwnode, "spiSclkPeriod") || >
