and armv6 architecures. The primary enhancement over the old design is
support for hierarchical interrupt controllers (such as a gpio driver
which can receive interrupts from a root PIC and act as a PIC itself for
clients interested in handling a change of gpio pin state as an
interrupt). The new code also provides an infrastructure for mapping
interrupts described in metadata in the form of a "controller reference
plus interrupt number" tuple into the simple "0-n" flat numeric space
understood by rman and the bus resource mechanisms.
Use of the new code is enabled by setting the ARM_INTRNG option, and by
making a few simple changes to the platform's support code. In addition
each existing PIC driver needs changes to be ready for INTRNG; this commit
contains the changes for the arm/gic driver, which most armv6 SoCs use, but
it does not enable the new code yet on any platform.
This project has been many years in the making, starting as a GSoC project
by Jakub Klama (jceel@) in 2012. That didn't get committed right away and
the source base evolved out from under it to some degree. In 2014 I rebased
the diffs to then -current and did some enhancements in the area of mapping
interrupt numbers and storing associated fdt data, then the project went
cold again for a while. Eventually Svata Kraus took that work in progress
and did another big round of work on it, removing most of the remaining
rough edges. Finally I took that and made one more pass through it, mostly
disabling the "INTR_SOLO" feature for now, pending further design
discussions on how to most efficiently dispatch a pending interrupt through
more than one layer of PIC. The current code with the INTR_SOLO feature
disabled uses approximate 100 extra cpu cycles for each cascaded PIC the
interrupt has to be passed to, so what's left to do is about efficiency, not
correct operation.
Differential Revision: https://reviews.freebsd.org/D2047
related to setting up static device mappings. Since it was only used by
arm/mv/mv_pci.c, it's now just static functions within that file, plus
one public function that gets called only from arm/mv/mv_machdep.c.
obsolete. This involves the following pieces:
- Remove it entirely on PowerPC, where it is not used by MD code either
- Remove all references to machine/fdt.h in non-architecture-specific code
(aside from uart_cpu_fdt.c, shared by ARM and MIPS, and so is somewhat
non-arch-specific).
- Fix code relying on header pollution from machine/fdt.h includes
- Legacy fdtbus.c (still used on x86 FDT systems) now passes resource
requests to its parent (nexus). This allows x86 FDT devices to allocate
both memory and IO requests and removes the last notionally MI use of
fdtbus_bs_tag.
- On those architectures that retain a machine/fdt.h, unused bits like
FDT_MAP_IRQ and FDT_INTR_MAX have been removed.
new devmap.[ch] files. Emphasize the MD nature of these things by using
the prefix arm_devmap_ on the function and type names (already a few of
these things found their way into MI code, hopefully it will be harder to
do by accident in the future).
out common code related to mapping device memory into a new devmap.c file.
Remove the growing duplication of code that used pmap_devmap_find_pa() and
then did some math with the returned results to generate a virtual address,
and likewise in reverse to get a physical address. Now there are a pair
of functions, arm_devmap_vtop() and arm_devmap_ptov(), to do that. The
bus_space_map() implementations are rewritten in terms of these.
included by vm/pmap.h, which is a prerequisite for arm/machine/pmap.h
so there's no reason to ever include it directly.
Thanks to alc@ for pointing this out.