MFC: r266470, r273546, r276017, r277932, r279153, r279778, r279780, r278797,
r278861, r280283, r280284, r280294, r280452, r280558, r280571, r281863,
r282049, r282357, r282440, r282441, r282358, r282359, r283550, r283918,
r290171, r290667, r290381, r290533, r290666, r292483, r295659, r297545,
r298305, r298383, r298428, r306489, r306557, r307067, r307068, r307087,
r307088, r307089, r307091, r307092, r307093, r307098, r307115, r307154,
r307240, r307241, r315967, r316476

Unbreak BCM2835/RPI-B support by bringing it in line with stable/11 and
head:

- Optimise reading of pending interrupt registers.

- Fix a bug where some DTS layouts could cause the premature ending of the
search (i.e. without returning any result) and you would end up with a
random MAC address.

- Reduce the diff between head and arm_intrng with the bcm2835 interrupt
controller.

- Allow the retrieving of the reserved pins state.

- Add support to the bcm2835 mailbox driver to work before interrupts are
enabled. This will be needed to enable the power on devices early on in the
boot process.

- Add support for enabling the USB on the Raspberry Pi boards when it hasn't
been done by U-Boot. This allows the USB to work when we load the kernel
directly.

- Call config_intrhook_disestablish on failure of the bcm2835 fb and fbd intr
hooks. With this we can get through the boot even if these functions fail.

- Add the structures needed to get/set the power state. These can be used
when, for example, we boot without U-Boot and wish to enable USB, or to
suspend an unneeded device.

- Add a mask to match only the relative base address of BSC controllers.

- Move the code to set the device power to the bcm2835 mailbox driver so it
can be reused by other drivers.

- Add the SOC_BCM2835 and SOC_BCM2836 options for the arm kernel and add the
former to std.bcm2835.

- Add a helper function to read clock frequencies from videocore and use this
to get the default frequency of the sdhci device.

- Add partial support for the Raspberry Pi 2.

- Remove a debug #error from the bcm2835 sdhci driver.

- Fetch the SDHCI frequency from videocore (our prefered source) and only if
it fails, fetch the clock-frequency from DTB. If both methods fail, use the
hardcoded default.

- Pass the supplied buffer length instead of a fixed size.

- Add the routines to query and setup the framebuffer state using the
BCM2835_MBOX_CHAN_PROP channel. The old channel (BCM2835_MBOX_CHAN_FB)
seems deprecated on recent firmware versions and is causing a freeze on
RPi 2.

- Fix DMA on RPi 2. BCM2836 has a different base address for peripherals.

- Enable DMA for sdhci on RPi 2 (BCM2836).

- Add a missing wakeup when releasing ownership of the SPI hardware.

- Fix framebuffer compatibility with new RPi firmware.

- Refactor bcm2835_cpufreq to use bcm2835_mbox_property API.

- Fix the sc(4) framebuffer driver on RPi 2.

- Fix the vt(4) framebuffer driver on RPi 2.

- Remove unused mutex and softc variables.

- Refactor mailbox property API to make it usable for /dev/vcio driver.

- Replace semaphore-base locking with sleep/wait synchronization.

- Fix infinite loop if response from VideoCore never received.

- Set have_message in interrupt to handle "response before READ" case.

- Serialize access to property channel when using bcm2835_mbox_property.

- Force framebuffer virtual viewport to be the same as physical.

- Use proper type of tag in bcm2835_mbox_fb_init.

- bcm2835_cpufreq: Only attach driver if we correcly match on the machine
compatible string.

- Add dev.fb.X.resync sysctl to resync ARM framebuffer with VideoCore.

- Do not use DMA channels used by GPU.

- Define local-intc for BCM2836 platform (RPI2) and make BCM2835 intc
a child of it.

- Fix build for Pi kernels with syscons enabled.

- Use VM_MEMATTR_WRITE_COMBINING memattr for mmap(2) on framebuffer.

- Make intc driver compatible with upstream DTS.

- Make Rapsberry Pi watchdog driver compatible with upstream DTS.

- Make sure intc is attached before interrupt consumers.

- Make framebuffer driver compatible with upstream DT.

- Add one more heuristic to determine MAC address of the SMSC device.

- Add compatibility strings from upstream DT.

- Fix spelling mistake, BCM2835_PASWORD -> BCM2835_PASSWORD.

Approved by: re (kib)

MFC r276298, r276303:

Remove the '#undef DEBUG' that should not be committed.

Removes unused and duplicate headers.

Bring the wait limit on mailbox write to a more sane value.

Fix a off-by-one bug on wait time limit.

Remove extra blank line.

MFC r275779, r275963, r276101, r276161, r276297:

Move ofw_cpu.c to sys/dev/ofw so that it can be used by other
architectures.

Add driver for CPU frequency/voltage control on the Raspberry Pi.

On initialization, do not use bcm_mbox_intr() to read the pending messages.
This fixes the hang that happens on boot while initializing the cpufreq on
Raspberry Pi.

MFC r261410

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

MFC: r261884

Correct the order of arguments to mtx_init().

PR: 186701
Submitted by: Takanori Sawada <tak.swd at gmail.com>

MFC r257199, r257200, r257217:

Remove all #include <machine/pmap.h> from arm code. It's already
included by vm/pmap.h, which is a prerequisite for arm/machine/pmap.h
so there's no reason to ever include it directly.

Remove #include <machine/frame.h> from all the arm code that doesn't
really need it. That would be almost everywhere it was included. Add
it in a couple files that really do need it and were previously getting
it by accident via another header.

Remove the last dregs of trapframe_t. It turns out only arm was using
this type, so remove it to make arm code more consistant with other
platforms.

MFC r276298, r276303:

Remove the '#undef DEBUG' that should not be committed.

Removes unused and duplicate headers.

Bring the wait limit on mailbox write to a more sane value.

Fix a off-by-one bug on wait time limit.

Remove extra blank line.

MFC r275779, r275963, r276101, r276161, r276297:

Move ofw_cpu.c to sys/dev/ofw so that it can be used by other
architectures.

Add driver for CPU frequency/voltage control on the Raspberry Pi.

On initialization, do not use bcm_mbox_intr() to read the pending messages.
This fixes the hang that happens on boot while initializing the cpufreq on
Raspberry Pi.

MFC r261410

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

MFC: r261884

Correct the order of arguments to mtx_init().

PR: 186701
Submitted by: Takanori Sawada <tak.swd at gmail.com>

MFC r257199, r257200, r257217:

Remove all #include <machine/pmap.h> from arm code. It's already
included by vm/pmap.h, which is a prerequisite for arm/machine/pmap.h
so there's no reason to ever include it directly.

Remove #include <machine/frame.h> from all the arm code that doesn't
really need it. That would be almost everywhere it was included. Add
it in a couple files that really do need it and were previously getting
it by accident via another header.

Remove the last dregs of trapframe_t. It turns out only arm was using
this type, so remove it to make arm code more consistant with other
platforms.