Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r269594, r269596, r269597, r269598, r269605, r269606:

Set ofwbus and simplebus to attach during BUS_PASS_BUS.

Define names that drivers can use to adjust their position relative to
other drivers within a BUS_PASS

Adjust ofwbus and simplebus to attach at BUS_PASS_ORDER_MIDDLE, so that
a platform can attach some other bus first if necessary.

Set the pl310 L2 cache driver to attach during the middle of BUS_PASS_CPU.

Attach arm generic interrupt and timer drivers in the middle of
BUS_PASS_INTERRUPT and BUS_PASS_TIMER, respectively.

Add an arm option, ARM_DEVICE_MULTIPASS, used to opt-in to multi-pass
device attachment on arm platforms. If this is defined, nexus attaches
early in BUS_PASS_BUS, and other busses and devices attach later, in the
pass number they are set up for. Without it defined, nexus attaches in
BUS_PASS_DEFAULT and thus so does everything else, which is status quo.

MFC 265861, 265870:

Make the hardware memory and instruction barrier functions work on armv4
and armv5 as well.

Add cpu_l2cache_drain_writebuf(), use it to implement generic_bs_barrier().

MFC 265440, 265441, 265444, 265445, 265446, 265447:

Move the pl310.enabled tunable to hw.pl310.enabled. Clean up a few minor
style(9) nits. Use DEVMETHOD_END.

Break out the code that figures out the L2 cache geometry to its own
routine, so that it can be called from multiple places in upcoming changes.

Call platform_pl310_init() before enabling the controller, and handle the
case where the controller is already enabled.

Add defines for the bits in the PL310 debug control register.

Add a public routine to set the L2 cache ram latencies. This can be
called by platform init routines to fine-tune cache performance.

Enable PL310 power-saving modes and tune the cache ram latencies for imx6.

MFC 265035: Move duplicated code to print l2 config into the common code.

MFC r261410

Follow r261352 by updating all drivers which are children of simplebus
to check the status property in their probe routines.

MFC r256647:

Invalidate the entire L2 cache before enabling it. Say whether it
has been enabled or disabled.

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

The errata 727915 requires a different workaround for r2p0, we have to
explicitely clean/invalidate every cache line using way/set operations.

Remove old declarations.

Release version check for erratum 727915 workaround in
l2_wbinv_range function implementation causes function
fail to flush caches for chip with RTL number 0x7. I failed
to find official PL310 revision with this RTL number
so further research on this matter required.

Fix the build:

* Use pl310_softc when the softc is otherwise unavailable.
* Use the correct spelling of sc_rtl_revision.

Only work around errata when we are on a part where the erratum applies.

Reviewed by: gonzo

PL310 driver update:

- Add pl310.disable tunable to disable L2 cache altogether. In
order to make sure that it's 100% disabled we use cache event
counters for cache line eviction and read allocate events
and panic if any of these counters increased. This is purely
for debugging purpose
- Direct access DEBUG_CTRL and CTRL might be unavailable in
unsecure mode, so use platform-specific functions for
these registers
- Replace #if 1 with proper erratum numbers
- Add erratum 753970 workaround
- Remove wait function for atomic operations
- Protect cache operations with spin mutex in order to prevent race condition
- Disable instruction cache prefetch and make sure data cache
prefetch is enabled in OMAP4-specific intialization

Make sure the address starts on a cache line boundary.

Merging projects/armv6, part 1

Cummulative patch of changes that are not vendor-specific:
- ARMv6 and ARMv7 architecture support
- ARM SMP support
- VFP/Neon support
- ARM Generic Interrupt Controller driver
- Simplification of startup code for all platforms