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 r261351, r261352, r261355, r261396, r261397, r261398, r261403, r261404,
r261405

Open Firmware interrupt specifiers can consist of arbitrary-length byte
strings and include arbitrary information (IRQ line/domain/sense). When the
ofw_bus_map_intr() API was introduced, it assumed that, as on most systems,
these were either 1 cell, containing an interrupt line, or 2, containing
a line number plus a sense code. It turns out a non-negligible number of
ARM systems use 3 (or even 4!) cells for interrupts, so make this more
general.

Provide a simpler and more standards-compliant simplebus implementation to
get the Routerboard 800 up and running with the vendor device tree. This
does not implement some BERI-specific features (which hopefully won't be
necessary soon), so move the old code to mips/beri, with a higher attach
priority when built, until MIPS interrupt domain support is rearranged.

Allow nesting of simplebuses.

Add a set of helpers (ofw_bus_get_status() and ofw_bus_status_okay()) to
process "status" properties of OF nodes.

Fix one remnant endian flaw in nexus.

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 r256932, r256938, r256966, r256953, r256967, r256969, r257015:

Add a new function (OF_getencprop()) that undoes the transformation applied
by encode-int. Specifically, it takes a set of 32-bit cell values and
changes them to host byte order. Most non-string instances of OF_getprop()
should be using this function, which is a no-op on big-endian platforms.

Use the new function all over the place.

MFC r256901, r256914 (by nwhitehorn):

Catch up on 6 years of improvements in Open Firmware nexus devices by
importing the sparc64 one. At least 90% of this code is MI and will be
moved into /sys/dev/ofw at some point in the future.

Ignore registers on devices where the reg property is malformed. Issue a
warning if this happens under bootverbose. This prevents some
strange-looking entries in dmesg for SMU devices on Apple G5 systems.

MFC r256814, r256816, r256818, r256846, r256855, r256864 (by nwhitehorn):

- Handle 2GB of ram
- Allow the OFW interrupt mapping code to work with PCI devices not
enumerated by Open Firmware, as in the case of FDT.
- Provide an interface for PCI bus drivers that need some of ofw_pci's
metadata during attach.
- Use standard ofw_bus helpers instead of reinventing the wheel.
- Make hard-wired TLB allocations be at minimum one page.

MFC r256792, r256793, r256799 (by nwhitehorn): Unify AIM and booke code.

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 r261351, r261352, r261355, r261396, r261397, r261398, r261403, r261404,
r261405

Open Firmware interrupt specifiers can consist of arbitrary-length byte
strings and include arbitrary information (IRQ line/domain/sense). When the
ofw_bus_map_intr() API was introduced, it assumed that, as on most systems,
these were either 1 cell, containing an interrupt line, or 2, containing
a line number plus a sense code. It turns out a non-negligible number of
ARM systems use 3 (or even 4!) cells for interrupts, so make this more
general.

Provide a simpler and more standards-compliant simplebus implementation to
get the Routerboard 800 up and running with the vendor device tree. This
does not implement some BERI-specific features (which hopefully won't be
necessary soon), so move the old code to mips/beri, with a higher attach
priority when built, until MIPS interrupt domain support is rearranged.

Allow nesting of simplebuses.

Add a set of helpers (ofw_bus_get_status() and ofw_bus_status_okay()) to
process "status" properties of OF nodes.

Fix one remnant endian flaw in nexus.

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 r256932, r256938, r256966, r256953, r256967, r256969, r257015:

Add a new function (OF_getencprop()) that undoes the transformation applied
by encode-int. Specifically, it takes a set of 32-bit cell values and
changes them to host byte order. Most non-string instances of OF_getprop()
should be using this function, which is a no-op on big-endian platforms.

Use the new function all over the place.

MFC r256901, r256914 (by nwhitehorn):

Catch up on 6 years of improvements in Open Firmware nexus devices by
importing the sparc64 one. At least 90% of this code is MI and will be
moved into /sys/dev/ofw at some point in the future.

Ignore registers on devices where the reg property is malformed. Issue a
warning if this happens under bootverbose. This prevents some
strange-looking entries in dmesg for SMU devices on Apple G5 systems.

MFC r256814, r256816, r256818, r256846, r256855, r256864 (by nwhitehorn):

- Handle 2GB of ram
- Allow the OFW interrupt mapping code to work with PCI devices not
enumerated by Open Firmware, as in the case of FDT.
- Provide an interface for PCI bus drivers that need some of ofw_pci's
metadata during attach.
- Use standard ofw_bus helpers instead of reinventing the wheel.
- Make hard-wired TLB allocations be at minimum one page.

MFC r256792, r256793, r256799 (by nwhitehorn): Unify AIM and booke code.