All architectures are now doing the same thing for irq__alloc_line:
1. Initialise a global counter to some fixed offset
2. Return the current value of the counter and increment it
This is better off in core code, with each architecture specifying the
initial offset, which is specific to the interrupt controller being used
by the guest.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Since irq__register_device no longer registers a device with anything,
rename it to irq__alloc_line, which better describes what is actually
going on.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
xics_init() assumes kvm->nrcpus is already setup. kvm->nrcpus is setup
in kvm_cpu_init()
Unfortunately xics_init() and kvm_cpu_init() both use base_init(). So
depending on the order randomly determined by the compiler, xics_init()
may initialised see kvm->nrcpus as 0 and not setup any of the icp VCPU
pointers. This manifests itself later in boot when trying to raise an
IRQ resulting in a null pointer deference/segv.
This moves xics_init() to use dev_base_init() to ensure it happens after
kvm_cpu_init().
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
In xics_init() we set the maximum server to kvm->nrcpus, and then set
the nr_servers using maximum server + 1.
That is off by one, in the harmless direction.
Simplify it to just set nr_servers = kvm->nrcpus.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
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>
Move all the non-arch specific members into a generic struct, and the arch specific
members into a arch specific kvm_arch. This prevents code duplication across different
archs.
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
This patch adds XICS emulation code (heavily borrowed from QEMU), and wires
this into kvm_cpu__irq() to fire a CPU IRQ via KVM. A device tree entry is
also added. IPIs work, xics_alloc_irqnum() is added to allocate an external
IRQ (which will later be used by the PHB PCI code) and finally, kvm__irq_line()
can be called to raise an IRQ on XICS.
Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Will Deacon