When userspace loads code and data in a read-only memory regions, KVM
needs to be able to handle this on arm and arm64.  Specifically this is
used when running code directly from a read-only flash device; the
common scenario is a UEFI blob loaded with the -bios option in QEMU.

Note that the MMIO exit on writes to a read-only memory is ABI and can
be used to emulate block-erase style flash devices.
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to
VCPUs. This patch extends current in-kernel PSCI emulation to provide
PSCI v0.2 interface to VCPUs.

By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for
keeping the ABI backward-compatible.

To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or
KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU
init using KVM_ARM_VCPU_INIT ioctl.
Signed-off-by: NAnup Patel <anup.patel@linaro.org>
Signed-off-by: NPranavkumar Sawargaonkar <pranavkumar@linaro.org>
Acked-by: NChristoffer Dall <christoffer.dall@linaro.org>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

Add infrastructure to handle distributor and cpu interface register
accesses through the KVM_{GET/SET}_DEVICE_ATTR interface by adding the
KVM_DEV_ARM_VGIC_GRP_DIST_REGS and KVM_DEV_ARM_VGIC_GRP_CPU_REGS groups
and defining the semantics of the attr field to be the MMIO offset as
specified in the GICv2 specs.

Missing register accesses or other changes in individual register access
functions to support save/restore of the VGIC state is added in
subsequent patches.
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

Support setting the distributor and cpu interface base addresses in the
VM physical address space through the KVM_{SET,GET}_DEVICE_ATTR API
in addition to the ARM specific API.

This has the added benefit of being able to share more code in user
space and do things in a uniform manner.

Also deprecate the older API at the same time, but backwards
compatibility will be maintained.
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

For migration to work we need to save (and later restore) the state of
each core's virtual generic timer.
Since this is per VCPU, we can use the [gs]et_one_reg ioctl and export
the three needed registers (control, counter, compare value).
Though they live in cp15 space, we don't use the existing list, since
they need special accessor functions and the arch timer is optional.
Acked-by: NMarc Zynger <marc.zyngier@arm.com>
Signed-off-by: NAndre Przywara <andre.przywara@linaro.org>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

This patch adds support for running Cortex-A7 guests on Cortex-A7 hosts.

As Cortex-A7 is architecturally compatible with A15, this patch is largely just
generalising existing code. Areas where 'implementation defined' behaviour
is identical for A7 and A15 is moved to allow it to be used by both cores.

The check to ensure that coprocessor register tables are sorted correctly is
also moved in to 'common' code to avoid each new cpu doing its own check
(and possibly forgetting to do so!)
Signed-off-by: NJonathan Austin <jonathan.austin@arm.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

On 32bit ARM, unsigned long is guaranteed to be a 32bit quantity.
On 64bit ARM, it is a 64bit quantity.

In order to be able to share code between the two architectures,
convert the registers to be unsigned long, so the core code can
be oblivious of the change.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

User space defines the model to emulate to a guest and should therefore
decide which addresses are used for both the virtual CPU interface
directly mapped in the guest physical address space and for the emulated
distributor interface, which is mapped in software by the in-kernel VGIC
support.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

On ARM some bits are specific to the model being emulated for the guest and
user space needs a way to tell the kernel about those bits.  An example is mmio
device base addresses, where KVM must know the base address for a given device
to properly emulate mmio accesses within a certain address range or directly
map a device with virtualiation extensions into the guest address space.

We make this API ARM-specific as we haven't yet reached a consensus for a
generic API for all KVM architectures that will allow us to do something like
this.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Implement the PSCI specification (ARM DEN 0022A) to control
virtual CPUs being "powered" on or off.

PSCI/KVM is detected using the KVM_CAP_ARM_PSCI capability.

A virtual CPU can now be initialized in a "powered off" state,
using the KVM_ARM_VCPU_POWER_OFF feature flag.

The guest can use either SMC or HVC to execute a PSCI function.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>

We use space #18 for floating point regs.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>

The Cache Size Selection Register (CSSELR) selects the current Cache
Size ID Register (CCSIDR).  You write which cache you are interested
in to CSSELR, and read the information out of CCSIDR.

Which cache numbers are valid is known by reading the Cache Level ID
Register (CLIDR).

To export this state to userspace, we add a KVM_REG_ARM_DEMUX
numberspace (17), which uses 8 bits to represent which register is
being demultiplexed (0 for CCSIDR), and the lower 8 bits to represent
this demultiplexing (in our case, the CSSELR value, which is 4 bits).
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>

All interrupt injection is now based on the VM ioctl KVM_IRQ_LINE.  This
works semantically well for the GIC as we in fact raise/lower a line on
a machine component (the gic).  The IOCTL uses the follwing struct.

struct kvm_irq_level {
	union {
		__u32 irq;     /* GSI */
		__s32 status;  /* not used for KVM_IRQ_LEVEL */
	};
	__u32 level;           /* 0 or 1 */
};

ARM can signal an interrupt either at the CPU level, or at the in-kernel irqchip
(GIC), and for in-kernel irqchip can tell the GIC to use PPIs designated for
specific cpus.  The irq field is interpreted like this:

  bits:  | 31 ... 24 | 23  ... 16 | 15    ...    0 |
  field: | irq_type  | vcpu_index |   irq_number   |

The irq_type field has the following values:
- irq_type[0]: out-of-kernel GIC: irq_number 0 is IRQ, irq_number 1 is FIQ
- irq_type[1]: in-kernel GIC: SPI, irq_number between 32 and 1019 (incl.)
               (the vcpu_index field is ignored)
- irq_type[2]: in-kernel GIC: PPI, irq_number between 16 and 31 (incl.)

The irq_number thus corresponds to the irq ID in as in the GICv2 specs.

This is documented in Documentation/kvm/api.txt.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>

Targets KVM support for Cortex A-15 processors.

Contains all the framework components, make files, header files, some
tracing functionality, and basic user space API.

Only supported core is Cortex-A15 for now.

Most functionality is in arch/arm/kvm/* or arch/arm/include/asm/kvm_*.h.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>