MFC r261423, r261424, r261516, r261513, r261562, r261563, r261564, r261565,
r261596, r261606

Add the imx sdhci controller.

Move Open Firmware device root on PowerPC, ARM, and MIPS systems to
a sub-node of nexus (ofwbus) rather than direct attach under nexus. This
fixes FDT on x86 and will make coexistence with ACPI on ARM systems easier.
SPARC is unchanged.

Add the missing ')' at end of sentence. Reword it to use a more common idiom.

Pass the kernel physical address to initarm through the boot param struct.

Make functions only used in vfp.c static, and remove vfp_enable.

Fix __syscall on armeb EABI. As it returns a 64-bit value it needs to
place 32-bit data in r1, not r0. 64-bit data is already packed correctly.

Use abp_physaddr for the physical address over KERNPHYSADDR. This helps us
remove the need to load the kernel at a fixed address.

Remove references to PHYSADDR where it's used only in debugging output.

Dynamically generate the page table. This will allow us to detect the
physical address we are loaded at to change the mapping.

MFC r256994, r257016, r257055, r257059, r257060, r257075

Add two new interfaces to ofw_bus:
- ofw_bus_map_intr()
Maps an (iparent, IRQ) tuple to a system-global interrupt number in some
platform dependent way. This is meant to be implemented as a replacement
for [FDT_]MAP_IRQ() that is an MI interface that knows about the bus
hierarchy.
- ofw_bus_config_intr()
Configures an interrupt (previously mapped) based on firmware sense flags.
This replaces manual interpretation of the sense field in bus drivers and
will, in a follow-up, allow that interpretation to be redirected to the PIC
drivers where it belongs. This will eventually replace the tables in
/sys/dev/fdt/fdt_ARCH.c

The PowerPC/AIM code has been converted to use these globally, with an
implementation in terms of MAP_IRQ() and powerpc_config_intr(), assuming
OpenPIC, at the bus root in nexus(4). The ofw_bus_config_intr() will shortly
be integrated into pic_if.m and bounced through nexus into the PIC tree.

Factor out MI portions of the PowerPC nexus device into /sys/dev/ofw. The
sparc64 driver will be modified to use this shortly.

Allow PIC drivers to translate firmware sense codes for themselves. This
is designed to replace the tables in dev/fdt/fdt_ARCH.c, but will not
happen quite yet.

Do not map IRQs twice. This fixes PowerPC/FDT systems with multiple PICs,
which would try to treat the previously-mapped interrupts from
fdt_decode_intr() as interrupt line numbers on the same parent PIC.

Remove some of the code required for supporting ssm(4) on SPARC in favor
of a more PowerPC/FDT-focused design. Whenever SPARC64 is integrated
into this rework, this should be (trivially) revisited.

MFC r256870, r256898, r256899, r256900 (by nwhitehorn):

Standards-conformance and code deduplication:
- Use bus reference phandles in place of FDT offsets as IRQ domain keys
- Unify the identical macio/fdt/mambo OpenPIC drivers into one
- Be more forgiving (following ePAPR) about what we need from the device
tree to identify an OpenPIC
- Correctly map all IRQs into an interrupt domain
- Set IRQ_*_CONFORM for interrupts on an unknown PIC type instead of
failing attachment for that device.

Allow lots of interrupts (useful on multi-domain platforms) and do not
set device_quiet() on all devices attached under nexus(4).

MFC r261423, r261424, r261516, r261513, r261562, r261563, r261564, r261565,
r261596, r261606

Add the imx sdhci controller.

Move Open Firmware device root on PowerPC, ARM, and MIPS systems to
a sub-node of nexus (ofwbus) rather than direct attach under nexus. This
fixes FDT on x86 and will make coexistence with ACPI on ARM systems easier.
SPARC is unchanged.

Add the missing ')' at end of sentence. Reword it to use a more common idiom.

Pass the kernel physical address to initarm through the boot param struct.

Make functions only used in vfp.c static, and remove vfp_enable.

Fix __syscall on armeb EABI. As it returns a 64-bit value it needs to
place 32-bit data in r1, not r0. 64-bit data is already packed correctly.

Use abp_physaddr for the physical address over KERNPHYSADDR. This helps us
remove the need to load the kernel at a fixed address.

Remove references to PHYSADDR where it's used only in debugging output.

Dynamically generate the page table. This will allow us to detect the
physical address we are loaded at to change the mapping.

MFC r256994, r257016, r257055, r257059, r257060, r257075

Add two new interfaces to ofw_bus:
- ofw_bus_map_intr()
Maps an (iparent, IRQ) tuple to a system-global interrupt number in some
platform dependent way. This is meant to be implemented as a replacement
for [FDT_]MAP_IRQ() that is an MI interface that knows about the bus
hierarchy.
- ofw_bus_config_intr()
Configures an interrupt (previously mapped) based on firmware sense flags.
This replaces manual interpretation of the sense field in bus drivers and
will, in a follow-up, allow that interpretation to be redirected to the PIC
drivers where it belongs. This will eventually replace the tables in
/sys/dev/fdt/fdt_ARCH.c

The PowerPC/AIM code has been converted to use these globally, with an
implementation in terms of MAP_IRQ() and powerpc_config_intr(), assuming
OpenPIC, at the bus root in nexus(4). The ofw_bus_config_intr() will shortly
be integrated into pic_if.m and bounced through nexus into the PIC tree.

Factor out MI portions of the PowerPC nexus device into /sys/dev/ofw. The
sparc64 driver will be modified to use this shortly.

Allow PIC drivers to translate firmware sense codes for themselves. This
is designed to replace the tables in dev/fdt/fdt_ARCH.c, but will not
happen quite yet.

Do not map IRQs twice. This fixes PowerPC/FDT systems with multiple PICs,
which would try to treat the previously-mapped interrupts from
fdt_decode_intr() as interrupt line numbers on the same parent PIC.

Remove some of the code required for supporting ssm(4) on SPARC in favor
of a more PowerPC/FDT-focused design. Whenever SPARC64 is integrated
into this rework, this should be (trivially) revisited.

MFC r256870, r256898, r256899, r256900 (by nwhitehorn):

Standards-conformance and code deduplication:
- Use bus reference phandles in place of FDT offsets as IRQ domain keys
- Unify the identical macio/fdt/mambo OpenPIC drivers into one
- Be more forgiving (following ePAPR) about what we need from the device
tree to identify an OpenPIC
- Correctly map all IRQs into an interrupt domain
- Set IRQ_*_CONFORM for interrupts on an unknown PIC type instead of
failing attachment for that device.

Allow lots of interrupts (useful on multi-domain platforms) and do not
set device_quiet() on all devices attached under nexus(4).