kvm tools: Fix powerpc build errors caused by recent changes

Several caused by commit 8074303 "remove global kvm object",
ioport__setup_arch(), term_getc_iov() & term_getc() in the
spapr_hvcons.c code, and kvm_cpu__reboot() in rtas_power_off().

Commit 221b584 "move active_console into struct kvm_config" added
checks in h_put_term_char() & h_get_term_char() of
kvm->cfg.active_console but needs to be vcpu->kvm->cfg.active_console.

That commit also missed updates to term_putc() & term_getc() in
spapr_rtas.c, and I'm guessing that we need similar checks of
active_console in rtas_put_term_char() & rtas_get_term_char().

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
kvm tools: Fix segfault on powerpc in xics_register()

In commit 06e6648 "move kvm_cpus into struct kvm", kvm_cpu__init() became
kvm_cpu__arch_init() called from a new kvm_cpu__init(), and the call was moved
from the end of the init sequence to much earlier, and in particular prior to
irq__init().

This leads to a segfault on powerpc, because kvm_cpu__arch_init() calls into
xics_cpu_register(), which dereferences vcpu->kvm.icp which is uninitialised
until irq__init().

Later in commit a48488d "use init/exit where possible", irq__init() was pulled
out of the init sequence and made a dev_base_init() routine, on x86. On powerpc
the call to irq__init() was dropped entirely.

Finally, we now have a circular dependency between kvm_cpu__init() (which needs
kvm->arch.icp), and irq__init() (which needs kvm->nrcpus). This is caused by
the combination of commit 89f40a7 "move nrcpus into struct kvm_config",
which moved the global nrcpus into kvm->cfg, and commit 06e6648 "move kvm_cpus
into struct kvm", which moved the setup of kvm->nrcpus from kvm->cfg into
kvm_cpu__init().

To fix it we drop irq__init() entirely, if we ever have a non xics irq option
we can bring it back. We turn xics_system_init() into xics_init(), and have it
do the allocation and setup of the icp/ics, including the per-vcpu setup,
removing the dependency from kvm_cpu__init() (via kvm_cpu__arch_init()).

xics_init() is a base_init() routine, it can't be core, which should be early
enough, fingers crossed.

Finally drop irq__exit(), it does nothing and is never called.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
kvm tools: Do setup_fdt() later, get powerpc to boot again

In commit e3d3ced "kernel load/firmware cleanup", the call to
kvm__arch_setup_firmware() was moved. Previously more or less at the end
of the init sequence, but that commit moved it into kvm__init() which
is a core_init() call and so runs quite early.

This broke booting powerpc guests, as setup_fdt() needs to be called
later in the setup sequence. In particular it looks at kvm->nrcpus,
which is uninitialised at that point.

In general setup_fdt() needs to run late in the sequence, as it encodes
the setup of the machine into the device tree.

So move setup_fdt() out of kvm__arch_setup_firmware() and make it a
firmware_init() call of its own.

With this patch I am able to boot guests again on HV KVM.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Pekka Enberg <penberg@kernel.org>