Add some the architected timer related infrastructure, and support timer
interrupt injection, which can happen as a resultof three possible
events:
- The virtual timer interrupt has fired while we were still
executing the guest
- The timer interrupt hasn't fired, but it expired while we
were doing the world switch
- A hrtimer we programmed earlier has fired
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add the init code for the hypervisor, the virtual machine, and
the virtual CPUs.
An interrupt handler is also wired to allow the VGIC maintenance
interrupts, used to deal with level triggered interrupts and LR
underflows.
A CPU hotplug notifier is registered to disable/enable the interrupt
as requested.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Plug the interrupt injection code. Interrupts can now be generated
from user space.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add VGIC virtual CPU interface code, picking pending interrupts
from the distributor and stashing them in the VGIC control interface
list registers.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add the GIC distributor emulation code. A number of the GIC features
are simply ignored as they are not required to boot a Linux guest.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marc 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: Will Deacon <will.deacon@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Wire the basic framework code for VGIC support and the initial in-kernel
MMIO support code for the VGIC, used for the distributor emulation.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
When an interrupt occurs for the guest, it is sometimes necessary
to find out which vcpu was running at that point.
Keep track of which vcpu is being run in kvm_arch_vcpu_ioctl_run(),
and allow the data to be retrieved using either:
- kvm_arm_get_running_vcpu(): returns the vcpu running at this point
on the current CPU. Can only be used in a non-preemptible context.
- kvm_arm_get_running_vcpus(): returns the per-CPU variable holding
the running vcpus, usable for per-CPU interrupts.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
From Will Deacon:
This set of changes moves the arch-timer driver out from arch/arm/ and
into drivers/clocksource and unifies the new driver with the arm64 copy.
* 'for-arm-soc/arch-timers' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux:
ARM: arch_timers: switch to physical timers if HYP mode is available
Documentation: Add ARMv8 to arch_timer devicetree
arm64: move from arm_generic to arm_arch_timer
arm64: arm_generic: prevent reading stale time
arm: arch_timer: move core to drivers/clocksource
arm: arch_timer: add arch_counter_set_user_access
arm: arch_timer: divorce from local_timer api
arm: arch_timer: add isbs to register accessors
arm: arch_timer: factor out register accessors
arm: arch_timer: split cntfrq accessor
arm: arch_timer: standardise counter reading
arm: arch_timer: use u64/u32 for register data
arm: arch_timer: remove redundant available check
arm: arch_timer: balance device_node refcounting
Signed-off-by: Olof Johansson <olof@lixom.net>
* 'for-rmk/perf' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux:
ARM: perf: simplify __hw_perf_event_init err handling
ARM: perf: remove unnecessary checks for idx < 0
ARM: perf: handle armpmu_register failing
ARM: perf: don't pretend to support counting of L1I writes
ARM: perf: remove redundant NULL check on cpu_pmu
ARM: Use implementor and part defines from cputype.h
ARM: Define CPU part numbers and implementors
-Compile fix for !SMP
-More cpu cluster id related fixes
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Merge tag 'highbank-fixes-for-3.8' of git://sources.calxeda.com/kernel/linux into fixes
From Rob Herring:
highbank fixes for 3.8
-Compile fix for !SMP
-More cpu cluster id related fixes
* tag 'highbank-fixes-for-3.8' of git://sources.calxeda.com/kernel/linux:
ARM: highbank: mask cluster id from cpu_logical_map
ARM: scu: mask cluster id from cpu_logical_map
ARM: scu: add empty scu_enable for !CONFIG_SMP
We have received multiple reports of mmap failures when running with a
2:2 vm split. These manifest as either -EINVAL with a non page-aligned
address (ending 0xaaa) or a SEGV, depending on the application. The
issue is commonly observed in children of make, which appears to use
bottom-up mmap (assumedly because it changes the stack rlimit).
Further investigation reveals that this regression was triggered by
394ef6403a ("mm: use vm_unmapped_area() on arm architecture"), whereby
TASK_UNMAPPED_BASE is no longer page-aligned for bottom-up mmap, causing
get_unmapped_area to choke on misaligned addressed.
This patch fixes the problem by defining TASK_UNMAPPED_BASE in terms of
TASK_SIZE and explicitly aligns the result to 16M, matching the other
end of the heap.
Acked-by: Nicolas Pitre <nico@linaro.org>
Reported-by: Steve Capper <steve.capper@arm.com>
Reported-by: Jean-Francois Moine <moinejf@free.fr>
Reported-by: Christoffer Dall <cdall@cs.columbia.edu>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 91c2ebb90b (ARM: 7114/1: cache-l2x0: add resume entry for l2
in secure mode) added resume entry for l2 in secure mode, but it missed
the dummy entry when CONFIG_CACHE_L2X0 is not set.
(Commit text edited by rmk.)
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This pull request adds initial support for the Tegra114 SoC, which
integrates a quad-core ARM Cortex-A15 CPU. I'm proud to observe that we
posted the initial versions of these patches before the final official
announcement of this chip.
These patches are enough to boot with a UART-based console, support the
Dalmore and Pluto reference/evaluation boards, instantiate the GPIO and
pinctrl drivers, and enable a cpuidle state. As yet, no clocks or
storage devices are supported, but patches for those will follow shortly.
This pull request is based on (most of) the previous pull request with
tag tegra-for-3.9-soc-cpuidle, followed by a merge of the previous pull
request with tag tegra-for-3.9-scu-base-rework.
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Merge tag 'tegra-for-3.9-soc-t114' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/soc
From Stepen Warren:
ARM: tegra: add Tegra114 SoC support
This pull request adds initial support for the Tegra114 SoC, which
integrates a quad-core ARM Cortex-A15 CPU. I'm proud to observe that we
posted the initial versions of these patches before the final official
announcement of this chip.
These patches are enough to boot with a UART-based console, support the
Dalmore and Pluto reference/evaluation boards, instantiate the GPIO and
pinctrl drivers, and enable a cpuidle state. As yet, no clocks or
storage devices are supported, but patches for those will follow shortly.
This pull request is based on (most of) the previous pull request with
tag tegra-for-3.9-soc-cpuidle, followed by a merge of the previous pull
request with tag tegra-for-3.9-scu-base-rework.
* tag 'tegra-for-3.9-soc-t114' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra: (24 commits)
ARM: DT: tegra114: add pinmux DT entry
ARM: DT: tegra114: add GPIO DT entry
ARM: tegra114: select PINCTRL for Tegra114 SoC
ARM: tegra: add Tegra114 ARM_CPUIDLE_WFI_STATE support
ARM: tegra: Add SMMU entry to Tegra114 DT
ARM: tegra: add AHB entry to Tegra114 DT
ARM: tegra: Add initial support for Tegra114 SoC.
ARM: dt: tegra114: Add new board, Pluto
ARM: dt: tegra114: Add new board, Dalmore
ARM: dt: tegra114: Add new SoC base, Tegra114 SoC
ARM: tegra: fuse: Add chip ID Tegra114 0x35
ARM: OMAP: Make use of available scu_a9_get_base() interface
ARM: tegra: Skip scu_enable(scu_base) if not Cortex A9
ARM: Add API to detect SCU base address from CP15
ARM: tegra: Use DT /cpu node to detect number of CPU core
ARM: tegra: Add CPU nodes to Tegra30 device tree
ARM: tegra: Add CPU nodes to Tegra20 device tree
ARM: perf: simplify __hw_perf_event_init err handling
ARM: perf: remove unnecessary checks for idx < 0
ARM: perf: handle armpmu_register failing
...
Signed-off-by: Olof Johansson <olof@lixom.net>
Remove/add conflict in arch/arm/mach-tegra/common.c resolved.
Remove/remove conflict in arch/arm/mach-tegra/platsmp.c. Leave the empty
stub function for now since removing it in the merge commit is confusing;
will be cleaned up in a separate commit. # # It looks like you may be
committing a merge. # If this is not correct, please remove the file #
.git/MERGE_HEAD # and try again.
Only alpha and sparc are unusual - they have ka_restorer in it.
And nobody needs that exposed to userland.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Traditionally for !CPU_CP15 read_cpuid and read_cpuid_ext returned the
processor id independent of the parameter passed in. This is wrong of
course but theoretically this doesn't harm because it's only called on
machines having a cp15.
Instead return 0 unconditionally which might make unused code paths be
better optimizable and so smaller and warn about unexpected usage.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Message-Id: 1359646587-1788-2-git-send-email-u.kleine-koenig@pengutronix.de
This makes cr_alignment a constant 0 to break code that tries to modify
the value as it's likely that it's built on wrong assumption when
CONFIG_CPU_CP15 isn't defined. For code that is only reading the value 0
is more or less a fine value to report.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Message-Id: 1358413196-5609-2-git-send-email-u.kleine-koenig@pengutronix.de (v8)
Add an empty version of scu_enable for !SMP builds. This fixes
compile error for highbank suspend code on !SMP builds.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
The core functionality of the arch_timer driver is not directly tied to
anything under arch/arm, and can be split out.
This patch factors out the core of the arch_timer driver, so it can be
shared with other architectures. A couple of functions are added so
that architecture-specific code can interact with the driver without
needing to touch its internals.
The ARM_ARCH_TIMER config variable is moved out to
drivers/clocksource/Kconfig, existing uses in arch/arm are replaced with
HAVE_ARM_ARCH_TIMER, which selects it.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Several bits in CNTKCTL reset to 0, including PL0VTEN. For architectures
using the generic timer which wish to have a fast gettimeofday vDSO
implementation, these bits must be set to 1 by the kernel. For
architectures without a vDSO, it's best to leave the bits set to 0 for
now to ensure that if and when support is added, it's implemented sanely
architecture wide.
As the bootloader might set PL0VTEN to a value that doesn't correspond
to that which the kernel prefers, we must explicitly set it to the
architecture port's preferred value.
This patch adds arch_counter_set_user_access, which sets the PL0 access
permissions to that required by the architecture. For arch/arm, this
currently means disabling all userspace access.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Without the isbs in arch_timer_get_cnt{p,v}ct the cpu may speculate
reads and return stale values. This could be bad for code sensitive to
changes in expected deltas between calls (e.g. the delay loop).
Without isbs in arch_timer_reg_write the processor may reorder
instructions around enabling/disabling of the timer or writing the
compare value, which we probably don't want.
This patch adds isbs to prevent those issues.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Currently the arch_timer register accessors are thrown together with
the main driver, preventing us from porting the driver to other
architectures.
This patch moves the register accessors into a header file, as with
the arm64 version. Constants required by the accessors are also moved.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
* Move sp810 header to a more generic location,
mainly to share it with arm64
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Merge tag 'vexpress/drivers-for-3.9' of git://git.linaro.org/people/pawelmoll/linux into next/drivers
From Pawel Moll:
Versatile Express related driver updates for 3.9:
* Move sp810 header to a more generic location,
mainly to share it with arm64
* tag 'vexpress/drivers-for-3.9' of git://git.linaro.org/people/pawelmoll/linux:
arm: Move sp810.h to include/linux/amba/
+ Linux 3.8-rc5
Signed-off-by: Olof Johansson <olof@lixom.net>
Since it is now used by code under drivers/clk/ it makes sense for this
file to be in a more generic location. This is required for building
vexpress support on arm64.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Pawel Moll <pawel.moll@arm.com>
Cc: Shiraz Hashim <shiraz.hashim@st.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Add API to detect SCU base address from CP15.
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
When unlocking a spinlock, all we need to do is increment the owner
field of the lock. Since only one CPU can be performing an unlock()
operation for a given lock, this doesn't need to be exclusive.
This patch simplifies arch_spin_unlock to use non-exclusive accesses
when updating the owner field of the lock.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
When the guest accesses I/O memory this will create data abort
exceptions and they are handled by decoding the HSR information
(physical address, read/write, length, register) and forwarding reads
and writes to QEMU which performs the device emulation.
Certain classes of load/store operations do not support the syndrome
information provided in the HSR. We don't support decoding these (patches
are available elsewhere), so we report an error to user space in this case.
This requires changing the general flow somewhat since new calls to run
the VCPU must check if there's a pending MMIO load and perform the write
after userspace has made the data available.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Handles the guest faults in KVM by mapping in corresponding user pages
in the 2nd stage page tables.
We invalidate the instruction cache by MVA whenever we map a page to the
guest (no, we cannot only do it when we have an iabt because the guest
may happily read/write a page before hitting the icache) if the hardware
uses VIPT or PIPT. In the latter case, we can invalidate only that
physical page. In the first case, all bets are off and we simply must
invalidate the whole affair. Not that VIVT icaches are tagged with
vmids, and we are out of the woods on that one. Alexander Graf was nice
enough to remind us of this massive pain.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
The following three ioctls are implemented:
- KVM_GET_REG_LIST
- KVM_GET_ONE_REG
- KVM_SET_ONE_REG
Now we have a table for all the cp15 registers, we can drive a generic
API.
The register IDs carry the following encoding:
ARM registers are mapped using the lower 32 bits. The upper 16 of that
is the register group type, or coprocessor number:
ARM 32-bit CP15 registers have the following id bit patterns:
0x4002 0000 000F <zero:1> <crn:4> <crm:4> <opc1:4> <opc2:3>
ARM 64-bit CP15 registers have the following id bit patterns:
0x4003 0000 000F <zero:1> <zero:4> <crm:4> <opc1:4> <zero:3>
For futureproofing, we need to tell QEMU about the CP15 registers the
host lets the guest access.
It will need this information to restore a current guest on a future
CPU or perhaps a future KVM which allow some of these to be changed.
We use a separate table for these, as they're only for the userspace API.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Adds a new important function in the main KVM/ARM code called
handle_exit() which is called from kvm_arch_vcpu_ioctl_run() on returns
from guest execution. This function examines the Hyp-Syndrome-Register
(HSR), which contains information telling KVM what caused the exit from
the guest.
Some of the reasons for an exit are CP15 accesses, which are
not allowed from the guest and this commit handles these exits by
emulating the intended operation in software and skipping the guest
instruction.
Minor notes about the coproc register reset:
1) We reserve a value of 0 as an invalid cp15 offset, to catch bugs in our
table, at cost of 4 bytes per vcpu.
2) Added comments on the table indicating how we handle each register, for
simplicity of understanding.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Provides complete world-switch implementation to switch to other guests
running in non-secure modes. Includes Hyp exception handlers that
capture necessary exception information and stores the information on
the VCPU and KVM structures.
The following Hyp-ABI is also documented in the code:
Hyp-ABI: Calling HYP-mode functions from host (in SVC mode):
Switching to Hyp mode is done through a simple HVC #0 instruction. The
exception vector code will check that the HVC comes from VMID==0 and if
so will push the necessary state (SPSR, lr_usr) on the Hyp stack.
- r0 contains a pointer to a HYP function
- r1, r2, and r3 contain arguments to the above function.
- The HYP function will be called with its arguments in r0, r1 and r2.
On HYP function return, we return directly to SVC.
A call to a function executing in Hyp mode is performed like the following:
<svc code>
ldr r0, =BSYM(my_hyp_fn)
ldr r1, =my_param
hvc #0 ; Call my_hyp_fn(my_param) from HYP mode
<svc code>
Otherwise, the world-switch is pretty straight-forward. All state that
can be modified by the guest is first backed up on the Hyp stack and the
VCPU values is loaded onto the hardware. State, which is not loaded, but
theoretically modifiable by the guest is protected through the
virtualiation features to generate a trap and cause software emulation.
Upon guest returns, all state is restored from hardware onto the VCPU
struct and the original state is restored from the Hyp-stack onto the
hardware.
SMP support using the VMPIDR calculated on the basis of the host MPIDR
and overriding the low bits with KVM vcpu_id contributed by Marc Zyngier.
Reuse of VMIDs has been implemented by Antonios Motakis and adapated from
a separate patch into the appropriate patches introducing the
functionality. Note that the VMIDs are stored per VM as required by the ARM
architecture reference manual.
To support VFP/NEON we trap those instructions using the HPCTR. When
we trap, we switch the FPU. After a guest exit, the VFP state is
returned to the host. When disabling access to floating point
instructions, we also mask FPEXC_EN in order to avoid the guest
receiving Undefined instruction exceptions before we have a chance to
switch back the floating point state. We are reusing vfp_hard_struct,
so we depend on VFPv3 being enabled in the host kernel, if not, we still
trap cp10 and cp11 in order to inject an undefined instruction exception
whenever the guest tries to use VFP/NEON. VFP/NEON developed by
Antionios Motakis and Rusty Russell.
Aborts that are permission faults, and not stage-1 page table walk, do
not report the faulting address in the HPFAR. We have to resolve the
IPA, and store it just like the HPFAR register on the VCPU struct. If
the IPA cannot be resolved, it means another CPU is playing with the
page tables, and we simply restart the guest. This quirk was fixed by
Marc Zyngier.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer 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: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
This commit introduces the framework for guest memory management
through the use of 2nd stage translation. Each VM has a pointer
to a level-1 table (the pgd field in struct kvm_arch) which is
used for the 2nd stage translations. Entries are added when handling
guest faults (later patch) and the table itself can be allocated and
freed through the following functions implemented in
arch/arm/kvm/arm_mmu.c:
- kvm_alloc_stage2_pgd(struct kvm *kvm);
- kvm_free_stage2_pgd(struct kvm *kvm);
Each entry in TLBs and caches are tagged with a VMID identifier in
addition to ASIDs. The VMIDs are assigned consecutively to VMs in the
order that VMs are executed, and caches and tlbs are invalidated when
the VMID space has been used to allow for more than 255 simultaenously
running guests.
The 2nd stage pgd is allocated in kvm_arch_init_vm(). The table is
freed in kvm_arch_destroy_vm(). Both functions are called from the main
KVM code.
We pre-allocate page table memory to be able to synchronize using a
spinlock and be called under rcu_read_lock from the MMU notifiers. We
steal the mmu_memory_cache implementation from x86 and adapt for our
specific usage.
We support MMU notifiers (thanks to Marc Zyngier) through
kvm_unmap_hva and kvm_set_spte_hva.
Finally, define kvm_phys_addr_ioremap() to map a device at a guest IPA,
which is used by VGIC support to map the virtual CPU interface registers
to the guest. This support is added by Marc Zyngier.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Sets up KVM code to handle all exceptions taken to Hyp mode.
When the kernel is booted in Hyp mode, calling an hvc instruction with r0
pointing to the new vectors, the HVBAR is changed to the the vector pointers.
This allows subsystems (like KVM here) to execute code in Hyp-mode with the
MMU disabled.
We initialize other Hyp-mode registers and enables the MMU for Hyp-mode from
the id-mapped hyp initialization code. Afterwards, the HVBAR is changed to
point to KVM Hyp vectors used to catch guest faults and to switch to Hyp mode
to perform a world-switch into a KVM guest.
Also provides memory mapping code to map required code pages, data structures,
and I/O regions accessed in Hyp mode at the same virtual address as the host
kernel virtual addresses, but which conforms to the architectural requirements
for translations in Hyp mode. This interface is added in arch/arm/kvm/arm_mmu.c
and comprises:
- create_hyp_mappings(from, to);
- create_hyp_io_mappings(from, to, phys_addr);
- free_hyp_pmds();
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer 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: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
