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: r258051, r258052

r258052:
Following the approach with ACPI DMAR on x86, split IOMMU handling into
a variant PCI bus instead of trying to shoehorn it into the PCI host bridge
adapter. Besides matching better the architecture on other platforms, this
also allows systems with multiple partitionable endpoints per PCI host
bridge to work correctly.

r258051:
Actually add IOMMU domain to the list of known mappings. This fixes a bug
where multiple devices in the same IOMMU domain would be allocated
conflicting mappings unless they also shared a DMA tag.

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: r258051, r258052

r258052:
Following the approach with ACPI DMAR on x86, split IOMMU handling into
a variant PCI bus instead of trying to shoehorn it into the PCI host bridge
adapter. Besides matching better the architecture on other platforms, this
also allows systems with multiple partitionable endpoints per PCI host
bridge to work correctly.

r258051:
Actually add IOMMU domain to the list of known mappings. This fixes a bug
where multiple devices in the same IOMMU domain would be allocated
conflicting mappings unless they also shared a DMA tag.