MFC: r317578

Fix a bug introduced as part of r287726 (MFCed to stable/10 in
r292789); use the right device_t for determining the softc of
the bridge in psycho_route_interrupt(). [1]
While at it, update the corresponding comment that the code in
question is also necessary for U30s in addition to E450s (a fact
that has been known for ages).

PR: 218478 [1]
Submitted by: Yoshihiko Iwama [1]

MFC: r287726

- Factor out the common and generic parts of the sparc64 host-PCI-bridge
drivers into the revived sys/sparc64/pci/ofw_pci.c, previously already
serving a similar purpose. This has been done with sun4v in mind, which
explains a) the otherwise not that obvious scheme employed and b) why
reusing sys/powerpc/ofw/ofw_pci.c was even lesser an option.
- Add a workaround for QEMU once again not emulating real machines, in
this case by not providing the OFW_PCI_CS_MEM64 range. [1]

Submitted by: jhb [1]

MFC r258800, r258802, r258805, r258806, r258807, r258851, r258857,
r259199, r259484, r259513, r259514, r259516

The kernel stack guard pages are only below the stack pointer, not above.

Remove unnecessary double-setting of the thread's onfault state in
copyinstr().

Open Firmware mandates that certain cross-references, in particular those
in /chosen, be ihandles. The ePAPR spec makes those cross-reference phandles,
since FDT has no concept of ihandles. Have the OF FDT CI module interpret
queries about ihandles as cross-reference phandles.

Real OF systems have an ihandle under /chosen/stdout, not a phandle. Use
the right type.

Rearchitect platform memory map parsing to make it less
Open Firmware-centric.

Remove fdtbus_bs_tag definition, which is now obsolete. The remainder of
this file is also slated for future demolition.

Return the correct IEEE 1275 code for "nextprop".

Use the common Open Firmware PCI interrupt routing code instead of the
duplicate version in dev/fdt.

Configure interrupt sense based on device tree information.

Simplify the ofw_bus_lookup_imap() API slightly: make it allocate maskbuf
internally instead of requiring the caller to allocate it.

MFC r258800, r258802, r258805, r258806, r258807, r258851, r258857,
r259199, r259484, r259513, r259514, r259516

The kernel stack guard pages are only below the stack pointer, not above.

Remove unnecessary double-setting of the thread's onfault state in
copyinstr().

Open Firmware mandates that certain cross-references, in particular those
in /chosen, be ihandles. The ePAPR spec makes those cross-reference phandles,
since FDT has no concept of ihandles. Have the OF FDT CI module interpret
queries about ihandles as cross-reference phandles.

Real OF systems have an ihandle under /chosen/stdout, not a phandle. Use
the right type.

Rearchitect platform memory map parsing to make it less
Open Firmware-centric.

Remove fdtbus_bs_tag definition, which is now obsolete. The remainder of
this file is also slated for future demolition.

Return the correct IEEE 1275 code for "nextprop".

Use the common Open Firmware PCI interrupt routing code instead of the
duplicate version in dev/fdt.

Configure interrupt sense based on device tree information.

Simplify the ofw_bus_lookup_imap() API slightly: make it allocate maskbuf
internally instead of requiring the caller to allocate it.