static int
acpi_pcib_pci_attach(device_t dev)
{
struct acpi_pcib_softc *sc;
ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
pcib_attach_common(dev);
sc = device_get_softc(dev);
sc->ap_handle = acpi_get_handle(dev);
return (acpi_pcib_attach(dev, &sc->ap_prt, sc->ap_pcibsc.secbus));
}
static int
acpi_pcib_acpi_attach(device_t dev)
{
struct acpi_hpcib_softc *sc;
ACPI_STATUS status;
static int bus0_seen = 0;
u_int addr, slot, func, busok;
uint8_t busno;
ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
sc = device_get_softc(dev);
sc->ap_dev = dev;
sc->ap_handle = acpi_get_handle(dev);
/*
* Get our segment number by evaluating _SEG
* It's OK for this to not exist.
*/
status = acpi_GetInteger(sc->ap_handle, "_SEG", &sc->ap_segment);
if (ACPI_FAILURE(status)) {
if (status != AE_NOT_FOUND) {
device_printf(dev, "could not evaluate _SEG - %s\n",
AcpiFormatException(status));
return_VALUE (ENXIO);
}
/* If it's not found, assume 0. */
sc->ap_segment = 0;
}
/*
* Get our base bus number by evaluating _BBN.
* If this doesn't work, we assume we're bus number 0.
*
* XXX note that it may also not exist in the case where we are
* meant to use a private configuration space mechanism for this bus,
* so we should dig out our resources and check to see if we have
* anything like that. How do we do this?
* XXX If we have the requisite information, and if we don't think the
* default PCI configuration space handlers can deal with this bus,
* we should attach our own handler.
* XXX invoke _REG on this for the PCI config space address space?
* XXX It seems many BIOS's with multiple Host-PCI bridges do not set
* _BBN correctly. They set _BBN to zero for all bridges. Thus,
* if _BBN is zero and PCI bus 0 already exists, we try to read our
* bus number from the configuration registers at address _ADR.
* We only do this for domain/segment 0 in the hopes that this is
* only needed for old single-domain machines.
*/
status = acpi_GetInteger(sc->ap_handle, "_BBN", &sc->ap_bus);
if (ACPI_FAILURE(status)) {
if (status != AE_NOT_FOUND) {
device_printf(dev, "could not evaluate _BBN - %s\n",
AcpiFormatException(status));
return_VALUE (ENXIO);
} else {
/* If it's not found, assume 0. */
sc->ap_bus = 0;
}
}
/*
* If this is segment 0, the bus is zero, and PCI bus 0 already
* exists, read the bus number via PCI config space.
*/
busok = 1;
if (sc->ap_segment == 0 && sc->ap_bus == 0 && bus0_seen) {
busok = 0;
status = acpi_GetInteger(sc->ap_handle, "_ADR", &addr);
if (ACPI_FAILURE(status)) {
if (status != AE_NOT_FOUND) {
device_printf(dev, "could not evaluate _ADR - %s\n",
AcpiFormatException(status));
return_VALUE (ENXIO);
} else
device_printf(dev, "couldn't find _ADR\n");
} else {
/* XXX: We assume bus 0. */
slot = ACPI_ADR_PCI_SLOT(addr);
func = ACPI_ADR_PCI_FUNC(addr);
if (bootverbose)
device_printf(dev, "reading config registers from 0:%d:%d\n",
slot, func);
if (host_pcib_get_busno(pci_cfgregread, 0, slot, func, &busno) == 0)
device_printf(dev, "couldn't read bus number from cfg space\n");
else {
sc->ap_bus = busno;
busok = 1;
}
}
}
/*
* If nothing else worked, hope that ACPI at least lays out the
* host-PCI bridges in order and that as a result our unit number
* is actually our bus number. There are several reasons this
* might not be true.
*/
if (busok == 0) {
sc->ap_bus = device_get_unit(dev);
device_printf(dev, "trying bus number %d\n", sc->ap_bus);
}
/* If this is bus 0 on segment 0, note that it has been seen already. */
if (sc->ap_segment == 0 && sc->ap_bus == 0)
bus0_seen = 1;
return (acpi_pcib_attach(dev, &sc->ap_prt, sc->ap_bus));
}