Commit Graph

575191 Commits

Author SHA1 Message Date
Marc Zyngier f1d67d4ac7 ARM: KVM: Rename struct coproc_reg::is_64 to is_64bit
As we're going to play some tricks on the struct coproc_reg,
make sure its 64bit indicator field matches that of coproc_params.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:22 +00:00
Marc Zyngier b613f59dd2 ARM: KVM: Enforce sorting of all CP tables
Since we're obviously terrible at sorting the CP tables, make sure
we're going to do it properly (or fail to boot). arm64 has had the
same mechanism for a while, and nobody ever broke it...

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:22 +00:00
Marc Zyngier 504bfce18a ARM: KVM: Properly sort the invariant table
Not having the invariant table properly sorted is an oddity, and
may get in the way of future optimisations. Let's fix it.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:22 +00:00
Marc Zyngier 623eefa8d0 arm64: KVM: Switch the sys_reg search to be a binary search
Our 64bit sys_reg table is about 90 entries long (so far, and the
PMU support is likely to increase this). This means that on average,
it takes 45 comparaisons to find the right entry (and actually the
full 90 if we have to search the invariant table).

Not the most efficient thing. Specially when you think that this
table is already sorted. Switching to a binary search effectively
reduces the search to about 7 comparaisons. Slightly better!

As an added bonus, the comparison is done by comparing all the
fields at once, instead of one at a time.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:22 +00:00
Shannon Zhao bb0c70bcca arm64: KVM: Add a new vcpu device control group for PMUv3
To configure the virtual PMUv3 overflow interrupt number, we use the
vcpu kvm_device ioctl, encapsulating the KVM_ARM_VCPU_PMU_V3_IRQ
attribute within the KVM_ARM_VCPU_PMU_V3_CTRL group.

After configuring the PMUv3, call the vcpu ioctl with attribute
KVM_ARM_VCPU_PMU_V3_INIT to initialize the PMUv3.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao f577f6c2a6 arm64: KVM: Introduce per-vcpu kvm device controls
In some cases it needs to get/set attributes specific to a vcpu and so
needs something else than ONE_REG.

Let's copy the KVM_DEVICE approach, and define the respective ioctls
for the vcpu file descriptor.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao 808e738142 arm64: KVM: Add a new feature bit for PMUv3
To support guest PMUv3, use one bit of the VCPU INIT feature array.
Initialize the PMU when initialzing the vcpu with that bit and PMU
overflow interrupt set.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao 5f0a714a2b arm64: KVM: Free perf event of PMU when destroying vcpu
When KVM frees VCPU, it needs to free the perf_event of PMU.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao 2aa36e9840 arm64: KVM: Reset PMU state when resetting vcpu
When resetting vcpu, it needs to reset the PMU state to initial status.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao b02386eb7d arm64: KVM: Add PMU overflow interrupt routing
When calling perf_event_create_kernel_counter to create perf_event,
assign a overflow handler. Then when the perf event overflows, set the
corresponding bit of guest PMOVSSET register. If this counter is enabled
and its interrupt is enabled as well, kick the vcpu to sync the
interrupt.

On VM entry, if there is counter overflowed and interrupt level is
changed, inject the interrupt with corresponding level. On VM exit, sync
the interrupt level as well if it has been changed.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao d692b8ad6e arm64: KVM: Add access handler for PMUSERENR register
This register resets as unknown in 64bit mode while it resets as zero
in 32bit mode. Here we choose to reset it as zero for consistency.

PMUSERENR_EL0 holds some bits which decide whether PMU registers can be
accessed from EL0. Add some check helpers to handle the access from EL0.

When these bits are zero, only reading PMUSERENR will trap to EL2 and
writing PMUSERENR or reading/writing other PMU registers will trap to
EL1 other than EL2 when HCR.TGE==0. To current KVM configuration
(HCR.TGE==0) there is no way to get these traps. Here we write 0xf to
physical PMUSERENR register on VM entry, so that it will trap PMU access
from EL0 to EL2. Within the register access handler we check the real
value of guest PMUSERENR register to decide whether this access is
allowed. If not allowed, return false to inject UND to guest.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao 76993739cd arm64: KVM: Add helper to handle PMCR register bits
According to ARMv8 spec, when writing 1 to PMCR.E, all counters are
enabled by PMCNTENSET, while writing 0 to PMCR.E, all counters are
disabled. When writing 1 to PMCR.P, reset all event counters, not
including PMCCNTR, to zero. When writing 1 to PMCR.C, reset PMCCNTR to
zero.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:21 +00:00
Shannon Zhao 7a0adc7064 arm64: KVM: Add access handler for PMSWINC register
Add access handler which emulates writing and reading PMSWINC
register and add support for creating software increment event.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao 76d883c4e6 arm64: KVM: Add access handler for PMOVSSET and PMOVSCLR register
Since the reset value of PMOVSSET and PMOVSCLR is UNKNOWN, use
reset_unknown for its reset handler. Add a handler to emulate writing
PMOVSSET or PMOVSCLR register.

When writing non-zero value to PMOVSSET, the counter and its interrupt
is enabled, kick this vcpu to sync PMU interrupt.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao 9db52c78cd arm64: KVM: Add access handler for PMINTENSET and PMINTENCLR register
Since the reset value of PMINTENSET and PMINTENCLR is UNKNOWN, use
reset_unknown for its reset handler. Add a handler to emulate writing
PMINTENSET or PMINTENCLR register.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao 9feb21ac57 arm64: KVM: Add access handler for event type register
These kind of registers include PMEVTYPERn, PMCCFILTR and PMXEVTYPER
which is mapped to PMEVTYPERn or PMCCFILTR.

The access handler translates all aarch32 register offsets to aarch64
ones and uses vcpu_sys_reg() to access their values to avoid taking care
of big endian.

When writing to these registers, create a perf_event for the selected
event type.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao 7f76635871 arm64: KVM: PMU: Add perf event map and introduce perf event creating function
When we use tools like perf on host, perf passes the event type and the
id of this event type category to kernel, then kernel will map them to
hardware event number and write this number to PMU PMEVTYPER<n>_EL0
register. When getting the event number in KVM, directly use raw event
type to create a perf_event for it.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao 96b0eebcc6 arm64: KVM: Add access handler for PMCNTENSET and PMCNTENCLR register
Since the reset value of PMCNTENSET and PMCNTENCLR is UNKNOWN, use
reset_unknown for its reset handler. Add a handler to emulate writing
PMCNTENSET or PMCNTENCLR register.

When writing to PMCNTENSET, call perf_event_enable to enable the perf
event. When writing to PMCNTENCLR, call perf_event_disable to disable
the perf event.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao 051ff581ce arm64: KVM: Add access handler for event counter register
These kind of registers include PMEVCNTRn, PMCCNTR and PMXEVCNTR which
is mapped to PMEVCNTRn.

The access handler translates all aarch32 register offsets to aarch64
ones and uses vcpu_sys_reg() to access their values to avoid taking care
of big endian.

When reading these registers, return the sum of register value and the
value perf event counts.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:20 +00:00
Shannon Zhao a86b550530 arm64: KVM: Add access handler for PMCEID0 and PMCEID1 register
Add access handler which gets host value of PMCEID0 or PMCEID1 when
guest access these registers. Writing action to PMCEID0 or PMCEID1 is
UNDEFINED.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:19 +00:00
Shannon Zhao 3965c3ce75 arm64: KVM: Add access handler for PMSELR register
Since the reset value of PMSELR_EL0 is UNKNOWN, use reset_unknown for
its reset handler. When reading PMSELR, return the PMSELR.SEL field to
guest.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:19 +00:00
Shannon Zhao ab9468340d arm64: KVM: Add access handler for PMCR register
Add reset handler which gets host value of PMCR_EL0 and make writable
bits architecturally UNKNOWN except PMCR.E which is zero. Add an access
handler for PMCR.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:19 +00:00
Shannon Zhao 04fe472615 arm64: KVM: Define PMU data structure for each vcpu
Here we plan to support virtual PMU for guest by full software
emulation, so define some basic structs and functions preparing for
futher steps. Define struct kvm_pmc for performance monitor counter and
struct kvm_pmu for performance monitor unit for each vcpu. According to
ARMv8 spec, the PMU contains at most 32(ARMV8_PMU_MAX_COUNTERS)
counters.

Since this only supports ARM64 (or PMUv3), add a separate config symbol
for it.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:19 +00:00
Marc Zyngier ad88213773 arm64: KVM: Add temporary kvm_perf_event.h
In order to merge the KVM/ARM PMU patches without creating a
conflict mess, let's have a temporary include file that won't
conflict with anything. Subsequent patches will clean that up.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:19 +00:00
Marc Zyngier 21a4179ce0 arm64: KVM: Move __cpu_init_stage2 after kvm_call_hyp
In order to ease the merge with the rest of the arm64 tree, move the
definition of __cpu_init_stage2() after what will be the new kvm_call_hyp.
Hopefully the resolution of the merge conflict will be obvious.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:19 +00:00
Marc Zyngier 68130cb5db ARM: KVM: Use common version of timer-sr.c
Using the common HYP timer code is a bit more tricky, since we
use system register names. Nothing a set of macros cannot
work around...

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:19 +00:00
Marc Zyngier b5fa5d3e62 ARM: KVM: Use common version of vgic-v2-sr.c
No need to keep our own private version, the common one is
strictly identical.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:19 +00:00
Marc Zyngier f1c9cad7c5 ARM: KVM: Move kvm/hyp/hyp.h to include/asm/kvm_hyp.h
In order to be able to use the code located in virt/kvm/arm/hyp,
we need to make the global hyp.h file accessible from include/asm,
similar to what we did for arm64.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:18 +00:00
Marc Zyngier 6d50d54cd8 arm64: KVM: Move vgic-v2 and timer save/restore to virt/kvm/arm/hyp
We already have virt/kvm/arm/ containing timer and vgic stuff.
Add yet another subdirectory to contain the hyp-specific files
(timer and vgic again).

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:18 +00:00
Marc Zyngier 13720a56ed arm64: KVM: Move kvm/hyp/hyp.h to include/asm/kvm_hyp.h
In order to be able to move code outside of kvm/hyp, we need to make
the global hyp.h file accessible from a standard location.

include/asm/kvm_hyp.h seems good enough.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:18 +00:00
Marc Zyngier 1f364c8c48 arm64: VHE: Add support for running Linux in EL2 mode
With ARMv8.1 VHE, the architecture is able to (almost) transparently
run the kernel at EL2, despite being written for EL1.

This patch takes care of the "almost" part, mostly preventing the kernel
from dropping from EL2 to EL1, and setting up the HYP configuration.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:18 +00:00
Marc Zyngier ae7e27fe68 arm64: hw_breakpoint: Allow EL2 breakpoints if running in HYP
With VHE, we place kernel {watch,break}-points at EL2 to get things
like kgdb and "perf -e mem:..." working.

This requires a bit of repainting in the low-level encore/decode,
but is otherwise pretty simple.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:18 +00:00
Marc Zyngier d98ecdaca2 arm64: perf: Count EL2 events if the kernel is running in HYP
When the kernel is running in HYP (with VHE), it is necessary to
include EL2 events if the user requests counting kernel or
hypervisor events.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:18 +00:00
Marc Zyngier 5f05a72aed arm64: KVM: Move most of the fault decoding to C
The fault decoding process (including computing the IPA in the case
of a permission fault) would be much better done in C code, as we
have a reasonable infrastructure to deal with the VHE/non-VHE
differences.

Let's move the whole thing to C, including the workaround for
erratum 834220, and just patch the odd ESR_EL2 access remaining
in hyp-entry.S.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:18 +00:00
Marc Zyngier 253dcbd39a arm64: KVM: VHE: Add alternative panic handling
As the kernel fully runs in HYP when VHE is enabled, we can
directly branch to the kernel's panic() implementation, and
not perform an exception return.

Add the alternative code to deal with this.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:18 +00:00
Marc Zyngier 77cb2d9133 arm64: KVM: VHE: Add fpsimd enabling on guest access
Despite the fact that a VHE enabled kernel runs at EL2, it uses
CPACR_EL1 to trap FPSIMD access. Add the required alternative
code to re-enable guest FPSIMD access when it has trapped to
EL2.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:17 +00:00
Marc Zyngier 5efe6de138 arm64: KVM: VHE: Use unified sysreg accessors for timer
Switch the timer code to the unified sysreg accessors.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:17 +00:00
Marc Zyngier 68908bf789 arm64: KVM: VHE: Implement VHE activate/deactivate_traps
Running the kernel in HYP mode requires the HCR_E2H bit to be set
at all times, and the HCR_TGE bit to be set when running as a host
(and cleared when running as a guest). At the same time, the vector
 must be set to the current role of the kernel (either host or
hypervisor), and a couple of system registers differ between VHE
and non-VHE.

We implement these by using another set of alternate functions
that get dynamically patched.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:17 +00:00
Marc Zyngier 328762247c arm64: KVM: VHE: Make __fpsimd_enabled VHE aware
As non-VHE and VHE have different ways to express the trapping of
FPSIMD registers to EL2, make __fpsimd_enabled a patchable predicate
and provide a VHE implementation.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:17 +00:00
Marc Zyngier d1526e5efc arm64: KVM: VHE: Enable minimal sysreg save/restore
We're now in a position where we can introduce VHE's minimal
save/restore, which is limited to the handful of shared sysregs.

Add the required alternative function calls that result in a
"do nothing" call on VHE, and the normal save/restore for non-VHE.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:17 +00:00
Marc Zyngier 094f8233c0 arm64: KVM: VHE: Use unified system register accessors
Use the recently introduced unified system register accessors for
those sysregs that behave differently depending on VHE being in
use or not.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:17 +00:00
Marc Zyngier 9c6c356832 arm64: KVM: VHE: Split save/restore of registers shared between guest and host
A handful of system registers are still shared between host and guest,
even while using VHE (tpidr*_el[01] and actlr_el1).

Also, some of the vcpu state (sp_el0, PC and PSTATE) must be
save/restored on entry/exit, as they are used on the host as well.

In order to facilitate the introduction of a VHE-specific sysreg
save/restore, make move the access to these registers to their
own save/restore functions.

No functional change.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:17 +00:00
Marc Zyngier edef528dc4 arm64: KVM: VHE: Differenciate host/guest sysreg save/restore
With ARMv8, host and guest share the same system register file,
making the save/restore procedure completely symetrical.
With VHE, host and guest now have different requirements, as they
use different sysregs.

In order to prepare for this, add split sysreg save/restore functions
for both host and guest. No functional changes yet.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:16 +00:00
Marc Zyngier 915ccd1dbf arm64: KVM: VHE: Introduce unified system register accessors
VHE brings its own bag of new system registers, or rather system
register accessors, as it define new ways to access both guest
and host system registers. For example, from the host:

- The host TCR_EL2 register is accessed using the TCR_EL1 accessor
- The guest TCR_EL1 register is accessed using the TCR_EL12 accessor

Obviously, this is confusing. A way to somehow reduce the complexity
of writing code for both ARMv8 and ARMv8.1 is to use a set of unified
accessors that will generate the right sysreg, depending on the mode
the CPU is running in. For example:

- read_sysreg_el1(tcr) will use TCR_EL1 on ARMv8, and TCR_EL12 on
  ARMv8.1 with VHE.
- read_sysreg_el2(tcr) will use TCR_EL2 on ARMv8, and TCR_EL1 on
  ARMv8.1 with VHE.

We end up with three sets of accessors ({read,write}_sysreg_el[012])
that can be directly used from C code. We take this opportunity to
also add the definition for the new VHE sysregs.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:16 +00:00
Marc Zyngier cedbb8b78c arm64: KVM: VHE: Patch out kern_hyp_va
The kern_hyp_va macro is pretty meaninless with VHE, as there is
only one mapping - the kernel one.

In order to keep the code readable and efficient, use runtime
patching to replace the 'and' instruction used to compute the VA
with a 'nop'.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:16 +00:00
Marc Zyngier b81125c791 arm64: KVM: VHE: Patch out use of HVC
With VHE, the host never issues an HVC instruction to get into the
KVM code, as we can simply branch there.

Use runtime code patching to simplify things a bit.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:16 +00:00
Marc Zyngier 1e947bad0b arm64: KVM: Skip HYP setup when already running in HYP
With the kernel running at EL2, there is no point trying to
configure page tables for HYP, as the kernel is already mapped.

Take this opportunity to refactor the whole init a bit, allowing
the various parts of the hypervisor bringup to be split across
multiple functions.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:16 +00:00
Marc Zyngier d88701bea3 arm64: Add ARM64_HAS_VIRT_HOST_EXTN feature
Add a new ARM64_HAS_VIRT_HOST_EXTN features to indicate that the
CPU has the ARMv8.1 VHE capability.

This will be used to trigger kernel patching in KVM.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:16 +00:00
Marc Zyngier f81f03fa23 arm64: Allow the arch timer to use the HYP timer
With the ARMv8.1 VHE, the kernel can run in HYP mode, and thus
use the HYP timer instead of the normal guest timer in a mostly
transparent way, except for the interrupt line.

This patch reworks the arch timer code to allow the selection of
the HYP PPI, possibly falling back to the guest timer if not
available.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:16 +00:00
Marc Zyngier 82deae0fc8 arm/arm64: Add new is_kernel_in_hyp_mode predicate
With ARMv8.1 VHE extension, it will be possible to run the kernel
at EL2 (aka HYP mode). In order for the kernel to easily find out
where it is running, add a new predicate that returns whether or
not the kernel is in HYP mode.

For completeness, the 32bit code also get such a predicate (always
returning false) so that code common to both architecture (timers,
KVM) can use it transparently.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29 18:34:16 +00:00