/*
* Copyright (C) 2013 ARM Limited, All Rights Reserved.
* 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, see <http://www.gnu.org/licenses/>.
*/
#include <linux/cpu.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/irqchip/arm-gic-v3.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
/* These are for GICv2 emulation only */
#define GICH_LR_VIRTUALID (0x3ffUL << 0)
#define GICH_LR_PHYSID_CPUID_SHIFT (10)
#define GICH_LR_PHYSID_CPUID (7UL << GICH_LR_PHYSID_CPUID_SHIFT)
#define ICH_LR_VIRTUALID_MASK (BIT_ULL(32) - 1)
/*
* LRs are stored in reverse order in memory. make sure we index them
* correctly.
*/
#define LR_INDEX(lr) (VGIC_V3_MAX_LRS - 1 - lr)
static u32 ich_vtr_el2;
static struct vgic_lr vgic_v3_get_lr(const struct kvm_vcpu *vcpu, int lr)
{
struct vgic_lr lr_desc;
u64 val = vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[LR_INDEX(lr)];
if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
lr_desc.irq = val & ICH_LR_VIRTUALID_MASK;
else
lr_desc.irq = val & GICH_LR_VIRTUALID;
lr_desc.source = 0;
if (lr_desc.irq <= 15 &&
vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2)
lr_desc.source = (val >> GICH_LR_PHYSID_CPUID_SHIFT) & 0x7;
lr_desc.state = 0;
if (val & ICH_LR_PENDING_BIT)
lr_desc.state |= LR_STATE_PENDING;
if (val & ICH_LR_ACTIVE_BIT)
lr_desc.state |= LR_STATE_ACTIVE;
if (val & ICH_LR_EOI)
lr_desc.state |= LR_EOI_INT;
return lr_desc;
}
static void vgic_v3_set_lr(struct kvm_vcpu *vcpu, int lr,
struct vgic_lr lr_desc)
{
u64 lr_val;
lr_val = lr_desc.irq;
/*
* Currently all guest IRQs are Group1, as Group0 would result
* in a FIQ in the guest, which it wouldn't expect.
* Eventually we want to make this configurable, so we may revisit
* this in the future.
*/
if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
lr_val |= ICH_LR_GROUP;
else
lr_val |= (u32)lr_desc.source << GICH_LR_PHYSID_CPUID_SHIFT;
if (lr_desc.state & LR_STATE_PENDING)
lr_val |= ICH_LR_PENDING_BIT;
if (lr_desc.state & LR_STATE_ACTIVE)
lr_val |= ICH_LR_ACTIVE_BIT;
if (lr_desc.state & LR_EOI_INT)
lr_val |= ICH_LR_EOI;
vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[LR_INDEX(lr)] = lr_val;
}
static void vgic_v3_sync_lr_elrsr(struct kvm_vcpu *vcpu, int lr,
struct vgic_lr lr_desc)
{
if (!(lr_desc.state & LR_STATE_MASK))
vcpu->arch.vgic_cpu.vgic_v3.vgic_elrsr |= (1U << lr);
}
static u64 vgic_v3_get_elrsr(const struct kvm_vcpu *vcpu)
{
return vcpu->arch.vgic_cpu.vgic_v3.vgic_elrsr;
}
static u64 vgic_v3_get_eisr(const struct kvm_vcpu *vcpu)
{
return vcpu->arch.vgic_cpu.vgic_v3.vgic_eisr;
}
static u32 vgic_v3_get_interrupt_status(const struct kvm_vcpu *vcpu)
{
u32 misr = vcpu->arch.vgic_cpu.vgic_v3.vgic_misr;
u32 ret = 0;
if (misr & ICH_MISR_EOI)
ret |= INT_STATUS_EOI;
if (misr & ICH_MISR_U)
ret |= INT_STATUS_UNDERFLOW;
return ret;
}
static 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;
}
static void vgic_v3_enable_underflow(struct kvm_vcpu *vcpu)
{
vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr |= ICH_HCR_UIE;
}
static void vgic_v3_disable_underflow(struct kvm_vcpu *vcpu)
{
vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr &= ~ICH_HCR_UIE;
}
static 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;
}
static 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;
/*
* 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;
}
static const struct vgic_ops vgic_v3_ops = {
.get_lr = vgic_v3_get_lr,
.set_lr = vgic_v3_set_lr,
.sync_lr_elrsr = vgic_v3_sync_lr_elrsr,
.get_elrsr = vgic_v3_get_elrsr,
.get_eisr = vgic_v3_get_eisr,
.get_interrupt_status = vgic_v3_get_interrupt_status,
.enable_underflow = vgic_v3_enable_underflow,
.disable_underflow = vgic_v3_disable_underflow,
.get_vmcr = vgic_v3_get_vmcr,
.set_vmcr = vgic_v3_set_vmcr,
.enable = vgic_v3_enable,
};
static struct vgic_params vgic_v3_params;
/**
* vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
* @node: pointer to the DT node
* @ops: address of a pointer to the GICv3 operations
* @params: address of a pointer to HW-specific parameters
*
* Returns 0 if a GICv3 has been found, with the low level operations
* in *ops and the HW parameters in *params. Returns an error code
* otherwise.
*/
int vgic_v3_probe(struct device_node *vgic_node,
const struct vgic_ops **ops,
const struct vgic_params **params)
{
int ret = 0;
u32 gicv_idx;
struct resource vcpu_res;
struct vgic_params *vgic = &vgic_v3_params;
vgic->maint_irq = irq_of_parse_and_map(vgic_node, 0);
if (!vgic->maint_irq) {
kvm_err("error getting vgic maintenance irq from DT\n");
ret = -ENXIO;
goto out;
}
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...
*/
vgic->nr_lr = (ich_vtr_el2 & 0xf) + 1;
vgic->can_emulate_gicv2 = false;
if (of_property_read_u32(vgic_node, "#redistributor-regions", &gicv_idx))
gicv_idx = 1;
gicv_idx += 3; /* Also skip GICD, GICC, GICH */
if (of_address_to_resource(vgic_node, gicv_idx, &vcpu_res)) {
kvm_info("GICv3: no GICV resource entry\n");
vgic->vcpu_base = 0;
} else if (!PAGE_ALIGNED(vcpu_res.start)) {
pr_warn("GICV physical address 0x%llx not page aligned\n",
(unsigned long long)vcpu_res.start);
vgic->vcpu_base = 0;
} else if (!PAGE_ALIGNED(resource_size(&vcpu_res))) {
pr_warn("GICV size 0x%llx not a multiple of page size 0x%lx\n",
(unsigned long long)resource_size(&vcpu_res),
PAGE_SIZE);
vgic->vcpu_base = 0;
} else {
vgic->vcpu_base = vcpu_res.start;
vgic->can_emulate_gicv2 = true;
kvm_register_device_ops(&kvm_arm_vgic_v2_ops,
KVM_DEV_TYPE_ARM_VGIC_V2);
}
if (vgic->vcpu_base == 0)
kvm_info("disabling GICv2 emulation\n");
kvm_register_device_ops(&kvm_arm_vgic_v3_ops, KVM_DEV_TYPE_ARM_VGIC_V3);
vgic->vctrl_base = NULL;
vgic->type = VGIC_V3;
vgic->max_gic_vcpus = KVM_MAX_VCPUS;
kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
vcpu_res.start, vgic->maint_irq);
*ops = &vgic_v3_ops;
*params = vgic;
out:
of_node_put(vgic_node);
return ret;
}
