diff options
author | Marc Zyngier <marc.zyngier@arm.com> | 2013-05-14 14:31:01 +0100 |
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committer | Gleb Natapov <gleb@redhat.com> | 2013-05-19 15:13:08 +0300 |
commit | 7275acdfe29ba03ad2f6e150386900c4e2d43fb1 (patch) | |
tree | 453d397f2d35e6f7f432fbd72f4b370f2606b665 /arch/arm/kvm/arch_timer.c | |
parent | 35af577aacb2fd2a6b407953044aea1cf0546fad (diff) | |
download | linux-7275acdfe29ba03ad2f6e150386900c4e2d43fb1.tar.bz2 |
ARM: KVM: move GIC/timer code to a common location
As KVM/arm64 is looming on the horizon, it makes sense to move some
of the common code to a single location in order to reduce duplication.
The code could live anywhere. Actually, most of KVM is already built
with a bunch of ugly ../../.. hacks in the various Makefiles, so we're
not exactly talking about style here. But maybe it is time to start
moving into a less ugly direction.
The include files must be in a "public" location, as they are accessed
from non-KVM files (arch/arm/kernel/asm-offsets.c).
For this purpose, introduce two new locations:
- virt/kvm/arm/ : x86 and ia64 already share the ioapic code in
virt/kvm, so this could be seen as a (very ugly) precedent.
- include/kvm/ : there is already an include/xen, and while the
intent is slightly different, this seems as good a location as
any
Eventually, we should probably have independant Makefiles at every
levels (just like everywhere else in the kernel), but this is just
the first step.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Diffstat (limited to 'arch/arm/kvm/arch_timer.c')
-rw-r--r-- | arch/arm/kvm/arch_timer.c | 272 |
1 files changed, 0 insertions, 272 deletions
diff --git a/arch/arm/kvm/arch_timer.c b/arch/arm/kvm/arch_timer.c deleted file mode 100644 index c55b6089e923..000000000000 --- a/arch/arm/kvm/arch_timer.c +++ /dev/null @@ -1,272 +0,0 @@ -/* - * Copyright (C) 2012 ARM Ltd. - * Author: Marc Zyngier <marc.zyngier@arm.com> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - */ - -#include <linux/cpu.h> -#include <linux/of_irq.h> -#include <linux/kvm.h> -#include <linux/kvm_host.h> -#include <linux/interrupt.h> - -#include <clocksource/arm_arch_timer.h> -#include <asm/arch_timer.h> - -#include <asm/kvm_vgic.h> -#include <asm/kvm_arch_timer.h> - -static struct timecounter *timecounter; -static struct workqueue_struct *wqueue; -static struct kvm_irq_level timer_irq = { - .level = 1, -}; - -static cycle_t kvm_phys_timer_read(void) -{ - return timecounter->cc->read(timecounter->cc); -} - -static bool timer_is_armed(struct arch_timer_cpu *timer) -{ - return timer->armed; -} - -/* timer_arm: as in "arm the timer", not as in ARM the company */ -static void timer_arm(struct arch_timer_cpu *timer, u64 ns) -{ - timer->armed = true; - hrtimer_start(&timer->timer, ktime_add_ns(ktime_get(), ns), - HRTIMER_MODE_ABS); -} - -static void timer_disarm(struct arch_timer_cpu *timer) -{ - if (timer_is_armed(timer)) { - hrtimer_cancel(&timer->timer); - cancel_work_sync(&timer->expired); - timer->armed = false; - } -} - -static void kvm_timer_inject_irq(struct kvm_vcpu *vcpu) -{ - struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; - - timer->cntv_ctl |= ARCH_TIMER_CTRL_IT_MASK; - kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id, - vcpu->arch.timer_cpu.irq->irq, - vcpu->arch.timer_cpu.irq->level); -} - -static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id) -{ - struct kvm_vcpu *vcpu = *(struct kvm_vcpu **)dev_id; - - /* - * We disable the timer in the world switch and let it be - * handled by kvm_timer_sync_hwstate(). Getting a timer - * interrupt at this point is a sure sign of some major - * breakage. - */ - pr_warn("Unexpected interrupt %d on vcpu %p\n", irq, vcpu); - return IRQ_HANDLED; -} - -static void kvm_timer_inject_irq_work(struct work_struct *work) -{ - struct kvm_vcpu *vcpu; - - vcpu = container_of(work, struct kvm_vcpu, arch.timer_cpu.expired); - vcpu->arch.timer_cpu.armed = false; - kvm_timer_inject_irq(vcpu); -} - -static enum hrtimer_restart kvm_timer_expire(struct hrtimer *hrt) -{ - struct arch_timer_cpu *timer; - timer = container_of(hrt, struct arch_timer_cpu, timer); - queue_work(wqueue, &timer->expired); - return HRTIMER_NORESTART; -} - -/** - * kvm_timer_flush_hwstate - prepare to move the virt timer to the cpu - * @vcpu: The vcpu pointer - * - * Disarm any pending soft timers, since the world-switch code will write the - * virtual timer state back to the physical CPU. - */ -void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu) -{ - struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; - - /* - * We're about to run this vcpu again, so there is no need to - * keep the background timer running, as we're about to - * populate the CPU timer again. - */ - timer_disarm(timer); -} - -/** - * kvm_timer_sync_hwstate - sync timer state from cpu - * @vcpu: The vcpu pointer - * - * Check if the virtual timer was armed and either schedule a corresponding - * soft timer or inject directly if already expired. - */ -void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) -{ - struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; - cycle_t cval, now; - u64 ns; - - if ((timer->cntv_ctl & ARCH_TIMER_CTRL_IT_MASK) || - !(timer->cntv_ctl & ARCH_TIMER_CTRL_ENABLE)) - return; - - cval = timer->cntv_cval; - now = kvm_phys_timer_read() - vcpu->kvm->arch.timer.cntvoff; - - BUG_ON(timer_is_armed(timer)); - - if (cval <= now) { - /* - * Timer has already expired while we were not - * looking. Inject the interrupt and carry on. - */ - kvm_timer_inject_irq(vcpu); - return; - } - - ns = cyclecounter_cyc2ns(timecounter->cc, cval - now); - timer_arm(timer, ns); -} - -void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) -{ - struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; - - INIT_WORK(&timer->expired, kvm_timer_inject_irq_work); - hrtimer_init(&timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); - timer->timer.function = kvm_timer_expire; - timer->irq = &timer_irq; -} - -static void kvm_timer_init_interrupt(void *info) -{ - enable_percpu_irq(timer_irq.irq, 0); -} - - -static int kvm_timer_cpu_notify(struct notifier_block *self, - unsigned long action, void *cpu) -{ - switch (action) { - case CPU_STARTING: - case CPU_STARTING_FROZEN: - kvm_timer_init_interrupt(NULL); - break; - case CPU_DYING: - case CPU_DYING_FROZEN: - disable_percpu_irq(timer_irq.irq); - break; - } - - return NOTIFY_OK; -} - -static struct notifier_block kvm_timer_cpu_nb = { - .notifier_call = kvm_timer_cpu_notify, -}; - -static const struct of_device_id arch_timer_of_match[] = { - { .compatible = "arm,armv7-timer", }, - {}, -}; - -int kvm_timer_hyp_init(void) -{ - struct device_node *np; - unsigned int ppi; - int err; - - timecounter = arch_timer_get_timecounter(); - if (!timecounter) - return -ENODEV; - - np = of_find_matching_node(NULL, arch_timer_of_match); - if (!np) { - kvm_err("kvm_arch_timer: can't find DT node\n"); - return -ENODEV; - } - - ppi = irq_of_parse_and_map(np, 2); - if (!ppi) { - kvm_err("kvm_arch_timer: no virtual timer interrupt\n"); - err = -EINVAL; - goto out; - } - - err = request_percpu_irq(ppi, kvm_arch_timer_handler, - "kvm guest timer", kvm_get_running_vcpus()); - if (err) { - kvm_err("kvm_arch_timer: can't request interrupt %d (%d)\n", - ppi, err); - goto out; - } - - timer_irq.irq = ppi; - - err = register_cpu_notifier(&kvm_timer_cpu_nb); - if (err) { - kvm_err("Cannot register timer CPU notifier\n"); - goto out_free; - } - - wqueue = create_singlethread_workqueue("kvm_arch_timer"); - if (!wqueue) { - err = -ENOMEM; - goto out_free; - } - - kvm_info("%s IRQ%d\n", np->name, ppi); - on_each_cpu(kvm_timer_init_interrupt, NULL, 1); - - goto out; -out_free: - free_percpu_irq(ppi, kvm_get_running_vcpus()); -out: - of_node_put(np); - return err; -} - -void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu) -{ - struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; - - timer_disarm(timer); -} - -int kvm_timer_init(struct kvm *kvm) -{ - if (timecounter && wqueue) { - kvm->arch.timer.cntvoff = kvm_phys_timer_read(); - kvm->arch.timer.enabled = 1; - } - - return 0; -} |