virt/kvm/arm/vgic/vgic-v3.c - kernel/msm-4.19 - Gitiles

 /*
  * 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, see <http://www.gnu.org/licenses/>.
  */

 #include <linux/irqchip/arm-gic-v3.h>
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
 #include <kvm/arm_vgic.h>
 #include <asm/kvm_mmu.h>
 #include <asm/kvm_asm.h>

 #include "vgic.h"

 void vgic_v3_process_maintenance(struct kvm_vcpu *vcpu)
 {
 	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
 	u32 model = vcpu->kvm->arch.vgic.vgic_model;

 	if (cpuif->vgic_misr & ICH_MISR_EOI) {
 		unsigned long eisr_bmap = cpuif->vgic_eisr;
 		int lr;

 		for_each_set_bit(lr, &eisr_bmap, kvm_vgic_global_state.nr_lr) {
 			u32 intid;
 			u64 val = cpuif->vgic_lr[lr];

 			if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
 				intid = val & ICH_LR_VIRTUAL_ID_MASK;
 			else
 				intid = val & GICH_LR_VIRTUALID;

 			WARN_ON(cpuif->vgic_lr[lr] & ICH_LR_STATE);

 			kvm_notify_acked_irq(vcpu->kvm, 0,
 					     intid - VGIC_NR_PRIVATE_IRQS);
 		}

 		/*
 		 * In the next iterations of the vcpu loop, if we sync
 		 * the vgic state after flushing it, but before
 		 * entering the guest (this happens for pending
 		 * signals and vmid rollovers), then make sure we
 		 * don't pick up any old maintenance interrupts here.
 		 */
 		cpuif->vgic_eisr = 0;
 	}

 	cpuif->vgic_hcr &= ~ICH_HCR_UIE;
 }

 void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
 {
 	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;

 	cpuif->vgic_hcr |= ICH_HCR_UIE;
 }

 void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
 {
 	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
 	int lr;

 	for (lr = 0; lr < vcpu->arch.vgic_cpu.used_lrs; lr++) {
 		u64 val = cpuif->vgic_lr[lr];
 		u32 intid;
 		struct vgic_irq *irq;

 		if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
 			intid = val & ICH_LR_VIRTUAL_ID_MASK;
 		else
 			intid = val & GICH_LR_VIRTUALID;
 		irq = vgic_get_irq(vcpu->kvm, vcpu, intid);

 		spin_lock(&irq->irq_lock);

 		/* Always preserve the active bit */
 		irq->active = !!(val & ICH_LR_ACTIVE_BIT);

 		/* Edge is the only case where we preserve the pending bit */
 		if (irq->config == VGIC_CONFIG_EDGE &&
 		    (val & ICH_LR_PENDING_BIT)) {
 			irq->pending = true;

 			if (vgic_irq_is_sgi(intid) &&
 			    model == KVM_DEV_TYPE_ARM_VGIC_V2) {
 				u32 cpuid = val & GICH_LR_PHYSID_CPUID;

 				cpuid >>= GICH_LR_PHYSID_CPUID_SHIFT;
 				irq->source |= (1 << cpuid);
 			}
 		}

 		/* Clear soft pending state when level irqs have been acked */
 		if (irq->config == VGIC_CONFIG_LEVEL &&
 		    !(val & ICH_LR_PENDING_BIT)) {
 			irq->soft_pending = false;
 			irq->pending = irq->line_level;
 		}

 		spin_unlock(&irq->irq_lock);
 	}
 }

 /* Requires the irq to be locked already */
 void vgic_v3_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
 {
 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
 	u64 val = irq->intid;

 	if (irq->pending) {
 		val |= ICH_LR_PENDING_BIT;

 		if (irq->config == VGIC_CONFIG_EDGE)
 			irq->pending = false;

 		if (vgic_irq_is_sgi(irq->intid) &&
 		    model == KVM_DEV_TYPE_ARM_VGIC_V2) {
 			u32 src = ffs(irq->source);

 			BUG_ON(!src);
 			val |= (src - 1) << GICH_LR_PHYSID_CPUID_SHIFT;
 			irq->source &= ~(1 << (src - 1));
 			if (irq->source)
 				irq->pending = true;
 		}
 	}

 	if (irq->active)
 		val |= ICH_LR_ACTIVE_BIT;

 	if (irq->hw) {
 		val |= ICH_LR_HW;
 		val |= ((u64)irq->hwintid) << ICH_LR_PHYS_ID_SHIFT;
 	} else {
 		if (irq->config == VGIC_CONFIG_LEVEL)
 			val |= ICH_LR_EOI;
 	}

 	/*
 	 * We currently only support Group1 interrupts, which is a
 	 * known defect. This needs to be addressed at some point.
 	 */
 	if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
 		val |= ICH_LR_GROUP;

 	val |= (u64)irq->priority << ICH_LR_PRIORITY_SHIFT;

 	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = val;
 }

 void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr)
 {
 	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = 0;
 }

 void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
 {
 	u32 vmcr;

 	vmcr  = (vmcrp->ctlr << ICH_VMCR_CTLR_SHIFT) & ICH_VMCR_CTLR_MASK;
 	vmcr |= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
 	vmcr |= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
 	vmcr |= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;

 	vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = vmcr;
 }

 void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
 {
 	u32 vmcr = vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr;

 	vmcrp->ctlr = (vmcr & ICH_VMCR_CTLR_MASK) >> ICH_VMCR_CTLR_SHIFT;
 	vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
 	vmcrp->bpr  = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
 	vmcrp->pmr  = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
 }

 void vgic_v3_enable(struct kvm_vcpu *vcpu)
 {
 	struct vgic_v3_cpu_if *vgic_v3 = &vcpu->arch.vgic_cpu.vgic_v3;

 	/*
 	 * By forcing VMCR to zero, the GIC will restore the binary
 	 * points to their reset values. Anything else resets to zero
 	 * anyway.
 	 */
 	vgic_v3->vgic_vmcr = 0;
 	vgic_v3->vgic_elrsr = ~0;

 	/*
 	 * If we are emulating a GICv3, we do it in an non-GICv2-compatible
 	 * way, so we force SRE to 1 to demonstrate this to the guest.
 	 * This goes with the spec allowing the value to be RAO/WI.
 	 */
 	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
 		vgic_v3->vgic_sre = ICC_SRE_EL1_SRE;
 	else
 		vgic_v3->vgic_sre = 0;

 	/* Get the show on the road... */
 	vgic_v3->vgic_hcr = ICH_HCR_EN;
 }

 /* check for overlapping regions and for regions crossing the end of memory */
 static bool vgic_v3_check_base(struct kvm *kvm)
 {
 	struct vgic_dist *d = &kvm->arch.vgic;
 	gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;

 	redist_size *= atomic_read(&kvm->online_vcpus);

 	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
 		return false;
 	if (d->vgic_redist_base + redist_size < d->vgic_redist_base)
 		return false;

 	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= d->vgic_redist_base)
 		return true;
 	if (d->vgic_redist_base + redist_size <= d->vgic_dist_base)
 		return true;

 	return false;
 }

 int vgic_v3_map_resources(struct kvm *kvm)
 {
 	int ret = 0;
 	struct vgic_dist *dist = &kvm->arch.vgic;

 	if (vgic_ready(kvm))
 		goto out;

 	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) ||
 	    IS_VGIC_ADDR_UNDEF(dist->vgic_redist_base)) {
 		kvm_err("Need to set vgic distributor addresses first\n");
 		ret = -ENXIO;
 		goto out;
 	}

 	if (!vgic_v3_check_base(kvm)) {
 		kvm_err("VGIC redist and dist frames overlap\n");
 		ret = -EINVAL;
 		goto out;
 	}

 	/*
 	 * For a VGICv3 we require the userland to explicitly initialize
 	 * the VGIC before we need to use it.
 	 */
 	if (!vgic_initialized(kvm)) {
 		ret = -EBUSY;
 		goto out;
 	}

 	ret = vgic_register_dist_iodev(kvm, dist->vgic_dist_base, VGIC_V3);
 	if (ret) {
 		kvm_err("Unable to register VGICv3 dist MMIO regions\n");
 		goto out;
 	}

 	ret = vgic_register_redist_iodevs(kvm, dist->vgic_redist_base);
 	if (ret) {
 		kvm_err("Unable to register VGICv3 redist MMIO regions\n");
 		goto out;
 	}

 	dist->ready = true;

 out:
 	if (ret)
 		kvm_vgic_destroy(kvm);
 	return ret;
 }

 /**
  * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
  * @node:	pointer to the DT node
  *
  * Returns 0 if a GICv3 has been found, returns an error code otherwise
  */
 int vgic_v3_probe(const struct gic_kvm_info *info)
 {
 	u32 ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);

 	/*
 	 * The ListRegs field is 5 bits, but there is a architectural
 	 * maximum of 16 list registers. Just ignore bit 4...
 	 */
 	kvm_vgic_global_state.nr_lr = (ich_vtr_el2 & 0xf) + 1;
 	kvm_vgic_global_state.can_emulate_gicv2 = false;

 	if (!info->vcpu.start) {
 		kvm_info("GICv3: no GICV resource entry\n");
 		kvm_vgic_global_state.vcpu_base = 0;
 	} else if (!PAGE_ALIGNED(info->vcpu.start)) {
 		pr_warn("GICV physical address 0x%llx not page aligned\n",
 			(unsigned long long)info->vcpu.start);
 		kvm_vgic_global_state.vcpu_base = 0;
 	} else if (!PAGE_ALIGNED(resource_size(&info->vcpu))) {
 		pr_warn("GICV size 0x%llx not a multiple of page size 0x%lx\n",
 			(unsigned long long)resource_size(&info->vcpu),
 			PAGE_SIZE);
 		kvm_vgic_global_state.vcpu_base = 0;
 	} else {
 		kvm_vgic_global_state.vcpu_base = info->vcpu.start;
 		kvm_vgic_global_state.can_emulate_gicv2 = true;
 		kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
 		kvm_info("vgic-v2@%llx\n", info->vcpu.start);
 	}
 	if (kvm_vgic_global_state.vcpu_base == 0)
 		kvm_info("disabling GICv2 emulation\n");
 	kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V3);

 	kvm_vgic_global_state.vctrl_base = NULL;
 	kvm_vgic_global_state.type = VGIC_V3;
 	kvm_vgic_global_state.max_gic_vcpus = VGIC_V3_MAX_CPUS;

 	return 0;
 }
	/*
	* 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, see <http://www.gnu.org/licenses/>.
	*/

	#include <linux/irqchip/arm-gic-v3.h>
	#include <linux/kvm.h>
	#include <linux/kvm_host.h>
	#include <kvm/arm_vgic.h>
	#include <asm/kvm_mmu.h>
	#include <asm/kvm_asm.h>

	#include "vgic.h"

	void vgic_v3_process_maintenance(struct kvm_vcpu *vcpu)
	{
	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
	u32 model = vcpu->kvm->arch.vgic.vgic_model;

	if (cpuif->vgic_misr & ICH_MISR_EOI) {
	unsigned long eisr_bmap = cpuif->vgic_eisr;
	int lr;

	for_each_set_bit(lr, &eisr_bmap, kvm_vgic_global_state.nr_lr) {
	u32 intid;
	u64 val = cpuif->vgic_lr[lr];

	if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
	intid = val & ICH_LR_VIRTUAL_ID_MASK;
	else
	intid = val & GICH_LR_VIRTUALID;

	WARN_ON(cpuif->vgic_lr[lr] & ICH_LR_STATE);

	kvm_notify_acked_irq(vcpu->kvm, 0,
	intid - VGIC_NR_PRIVATE_IRQS);
	}

	/*
	* In the next iterations of the vcpu loop, if we sync
	* the vgic state after flushing it, but before
	* entering the guest (this happens for pending
	* signals and vmid rollovers), then make sure we
	* don't pick up any old maintenance interrupts here.
	*/
	cpuif->vgic_eisr = 0;
	}

	cpuif->vgic_hcr &= ~ICH_HCR_UIE;
	}

	void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
	{
	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;

	cpuif->vgic_hcr \|= ICH_HCR_UIE;
	}

	void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
	{
	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
	u32 model = vcpu->kvm->arch.vgic.vgic_model;
	int lr;

	for (lr = 0; lr < vcpu->arch.vgic_cpu.used_lrs; lr++) {
	u64 val = cpuif->vgic_lr[lr];
	u32 intid;
	struct vgic_irq *irq;

	if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
	intid = val & ICH_LR_VIRTUAL_ID_MASK;
	else
	intid = val & GICH_LR_VIRTUALID;
	irq = vgic_get_irq(vcpu->kvm, vcpu, intid);

	spin_lock(&irq->irq_lock);

	/* Always preserve the active bit */
	irq->active = !!(val & ICH_LR_ACTIVE_BIT);

	/* Edge is the only case where we preserve the pending bit */
	if (irq->config == VGIC_CONFIG_EDGE &&
	(val & ICH_LR_PENDING_BIT)) {
	irq->pending = true;

	if (vgic_irq_is_sgi(intid) &&
	model == KVM_DEV_TYPE_ARM_VGIC_V2) {
	u32 cpuid = val & GICH_LR_PHYSID_CPUID;

	cpuid >>= GICH_LR_PHYSID_CPUID_SHIFT;
	irq->source \|= (1 << cpuid);
	}
	}

	/* Clear soft pending state when level irqs have been acked */
	if (irq->config == VGIC_CONFIG_LEVEL &&
	!(val & ICH_LR_PENDING_BIT)) {
	irq->soft_pending = false;
	irq->pending = irq->line_level;
	}

	spin_unlock(&irq->irq_lock);
	}
	}

	/* Requires the irq to be locked already */
	void vgic_v3_populate_lr(struct kvm_vcpu vcpu, struct vgic_irq irq, int lr)
	{
	u32 model = vcpu->kvm->arch.vgic.vgic_model;
	u64 val = irq->intid;

	if (irq->pending) {
	val \|= ICH_LR_PENDING_BIT;

	if (irq->config == VGIC_CONFIG_EDGE)
	irq->pending = false;

	if (vgic_irq_is_sgi(irq->intid) &&
	model == KVM_DEV_TYPE_ARM_VGIC_V2) {
	u32 src = ffs(irq->source);

	BUG_ON(!src);
	val \|= (src - 1) << GICH_LR_PHYSID_CPUID_SHIFT;
	irq->source &= ~(1 << (src - 1));
	if (irq->source)
	irq->pending = true;
	}
	}

	if (irq->active)
	val \|= ICH_LR_ACTIVE_BIT;

	if (irq->hw) {
	val \|= ICH_LR_HW;
	val \|= ((u64)irq->hwintid) << ICH_LR_PHYS_ID_SHIFT;
	} else {
	if (irq->config == VGIC_CONFIG_LEVEL)
	val \|= ICH_LR_EOI;
	}

	/*
	* We currently only support Group1 interrupts, which is a
	* known defect. This needs to be addressed at some point.
	*/
	if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
	val \|= ICH_LR_GROUP;

	val \|= (u64)irq->priority << ICH_LR_PRIORITY_SHIFT;

	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = val;
	}

	void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr)
	{
	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = 0;
	}

	void vgic_v3_set_vmcr(struct kvm_vcpu vcpu, struct vgic_vmcr vmcrp)
	{
	u32 vmcr;

	vmcr = (vmcrp->ctlr << ICH_VMCR_CTLR_SHIFT) & ICH_VMCR_CTLR_MASK;
	vmcr \|= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
	vmcr \|= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
	vmcr \|= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;

	vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = vmcr;
	}

	void vgic_v3_get_vmcr(struct kvm_vcpu vcpu, struct vgic_vmcr vmcrp)
	{
	u32 vmcr = vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr;

	vmcrp->ctlr = (vmcr & ICH_VMCR_CTLR_MASK) >> ICH_VMCR_CTLR_SHIFT;
	vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
	vmcrp->bpr = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
	vmcrp->pmr = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
	}

	void vgic_v3_enable(struct kvm_vcpu *vcpu)
	{
	struct vgic_v3_cpu_if *vgic_v3 = &vcpu->arch.vgic_cpu.vgic_v3;

	/*
	* By forcing VMCR to zero, the GIC will restore the binary
	* points to their reset values. Anything else resets to zero
	* anyway.
	*/
	vgic_v3->vgic_vmcr = 0;
	vgic_v3->vgic_elrsr = ~0;

	/*
	* If we are emulating a GICv3, we do it in an non-GICv2-compatible
	* way, so we force SRE to 1 to demonstrate this to the guest.
	* This goes with the spec allowing the value to be RAO/WI.
	*/
	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
	vgic_v3->vgic_sre = ICC_SRE_EL1_SRE;
	else
	vgic_v3->vgic_sre = 0;

	/* Get the show on the road... */
	vgic_v3->vgic_hcr = ICH_HCR_EN;
	}

	/* check for overlapping regions and for regions crossing the end of memory */
	static bool vgic_v3_check_base(struct kvm *kvm)
	{
	struct vgic_dist *d = &kvm->arch.vgic;
	gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;

	redist_size *= atomic_read(&kvm->online_vcpus);

	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
	return false;
	if (d->vgic_redist_base + redist_size < d->vgic_redist_base)
	return false;

	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= d->vgic_redist_base)
	return true;
	if (d->vgic_redist_base + redist_size <= d->vgic_dist_base)
	return true;

	return false;
	}

	int vgic_v3_map_resources(struct kvm *kvm)
	{
	int ret = 0;
	struct vgic_dist *dist = &kvm->arch.vgic;

	if (vgic_ready(kvm))
	goto out;

	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) \|\|
	IS_VGIC_ADDR_UNDEF(dist->vgic_redist_base)) {
	kvm_err("Need to set vgic distributor addresses first\n");
	ret = -ENXIO;
	goto out;
	}

	if (!vgic_v3_check_base(kvm)) {
	kvm_err("VGIC redist and dist frames overlap\n");
	ret = -EINVAL;
	goto out;
	}

	/*
	* For a VGICv3 we require the userland to explicitly initialize
	* the VGIC before we need to use it.
	*/
	if (!vgic_initialized(kvm)) {
	ret = -EBUSY;
	goto out;
	}

	ret = vgic_register_dist_iodev(kvm, dist->vgic_dist_base, VGIC_V3);
	if (ret) {
	kvm_err("Unable to register VGICv3 dist MMIO regions\n");
	goto out;
	}

	ret = vgic_register_redist_iodevs(kvm, dist->vgic_redist_base);
	if (ret) {
	kvm_err("Unable to register VGICv3 redist MMIO regions\n");
	goto out;
	}

	dist->ready = true;

	out:
	if (ret)
	kvm_vgic_destroy(kvm);
	return ret;
	}

	/**
	* vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
	* @node: pointer to the DT node
	*
	* Returns 0 if a GICv3 has been found, returns an error code otherwise
	*/
	int vgic_v3_probe(const struct gic_kvm_info *info)
	{
	u32 ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);

	/*
	* The ListRegs field is 5 bits, but there is a architectural
	* maximum of 16 list registers. Just ignore bit 4...
	*/
	kvm_vgic_global_state.nr_lr = (ich_vtr_el2 & 0xf) + 1;
	kvm_vgic_global_state.can_emulate_gicv2 = false;

	if (!info->vcpu.start) {
	kvm_info("GICv3: no GICV resource entry\n");
	kvm_vgic_global_state.vcpu_base = 0;
	} else if (!PAGE_ALIGNED(info->vcpu.start)) {
	pr_warn("GICV physical address 0x%llx not page aligned\n",
	(unsigned long long)info->vcpu.start);
	kvm_vgic_global_state.vcpu_base = 0;
	} else if (!PAGE_ALIGNED(resource_size(&info->vcpu))) {
	pr_warn("GICV size 0x%llx not a multiple of page size 0x%lx\n",
	(unsigned long long)resource_size(&info->vcpu),
	PAGE_SIZE);
	kvm_vgic_global_state.vcpu_base = 0;
	} else {
	kvm_vgic_global_state.vcpu_base = info->vcpu.start;
	kvm_vgic_global_state.can_emulate_gicv2 = true;
	kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
	kvm_info("vgic-v2@%llx\n", info->vcpu.start);
	}
	if (kvm_vgic_global_state.vcpu_base == 0)
	kvm_info("disabling GICv2 emulation\n");
	kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V3);

	kvm_vgic_global_state.vctrl_base = NULL;
	kvm_vgic_global_state.type = VGIC_V3;
	kvm_vgic_global_state.max_gic_vcpus = VGIC_V3_MAX_CPUS;

	return 0;
	}