linux/virt/kvm/arm/vgic-v2.c
Andre Przywara b5d84ff600 arm/arm64: KVM: enable kernel side of GICv3 emulation
With all the necessary GICv3 emulation code in place, we can now
connect the code to the GICv3 backend in the kernel.
The LR register handling is different depending on the emulated GIC
model, so provide different implementations for each.
Also allow non-v2-compatible GICv3 implementations (which don't
provide MMIO regions for the virtual CPU interface in the DT), but
restrict those hosts to support GICv3 guests only.
If the device tree provides a GICv2 compatible GICV resource entry,
but that one is faulty, just disable the GICv2 emulation and let the
user use at least the GICv3 emulation for guests.
To provide proper support for the legacy KVM_CREATE_IRQCHIP ioctl,
note virtual GICv2 compatibility in struct vgic_params and use it
on creating a VGICv2.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-20 18:25:32 +01:00

252 lines
6.8 KiB
C

/*
* Copyright (C) 2012,2013 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.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
static struct vgic_lr vgic_v2_get_lr(const struct kvm_vcpu *vcpu, int lr)
{
struct vgic_lr lr_desc;
u32 val = vcpu->arch.vgic_cpu.vgic_v2.vgic_lr[lr];
lr_desc.irq = val & GICH_LR_VIRTUALID;
if (lr_desc.irq <= 15)
lr_desc.source = (val >> GICH_LR_PHYSID_CPUID_SHIFT) & 0x7;
else
lr_desc.source = 0;
lr_desc.state = 0;
if (val & GICH_LR_PENDING_BIT)
lr_desc.state |= LR_STATE_PENDING;
if (val & GICH_LR_ACTIVE_BIT)
lr_desc.state |= LR_STATE_ACTIVE;
if (val & GICH_LR_EOI)
lr_desc.state |= LR_EOI_INT;
return lr_desc;
}
static void vgic_v2_set_lr(struct kvm_vcpu *vcpu, int lr,
struct vgic_lr lr_desc)
{
u32 lr_val = (lr_desc.source << GICH_LR_PHYSID_CPUID_SHIFT) | lr_desc.irq;
if (lr_desc.state & LR_STATE_PENDING)
lr_val |= GICH_LR_PENDING_BIT;
if (lr_desc.state & LR_STATE_ACTIVE)
lr_val |= GICH_LR_ACTIVE_BIT;
if (lr_desc.state & LR_EOI_INT)
lr_val |= GICH_LR_EOI;
vcpu->arch.vgic_cpu.vgic_v2.vgic_lr[lr] = lr_val;
}
static void vgic_v2_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_v2.vgic_elrsr |= (1ULL << lr);
}
static u64 vgic_v2_get_elrsr(const struct kvm_vcpu *vcpu)
{
return vcpu->arch.vgic_cpu.vgic_v2.vgic_elrsr;
}
static u64 vgic_v2_get_eisr(const struct kvm_vcpu *vcpu)
{
return vcpu->arch.vgic_cpu.vgic_v2.vgic_eisr;
}
static u32 vgic_v2_get_interrupt_status(const struct kvm_vcpu *vcpu)
{
u32 misr = vcpu->arch.vgic_cpu.vgic_v2.vgic_misr;
u32 ret = 0;
if (misr & GICH_MISR_EOI)
ret |= INT_STATUS_EOI;
if (misr & GICH_MISR_U)
ret |= INT_STATUS_UNDERFLOW;
return ret;
}
static void vgic_v2_enable_underflow(struct kvm_vcpu *vcpu)
{
vcpu->arch.vgic_cpu.vgic_v2.vgic_hcr |= GICH_HCR_UIE;
}
static void vgic_v2_disable_underflow(struct kvm_vcpu *vcpu)
{
vcpu->arch.vgic_cpu.vgic_v2.vgic_hcr &= ~GICH_HCR_UIE;
}
static void vgic_v2_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
{
u32 vmcr = vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr;
vmcrp->ctlr = (vmcr & GICH_VMCR_CTRL_MASK) >> GICH_VMCR_CTRL_SHIFT;
vmcrp->abpr = (vmcr & GICH_VMCR_ALIAS_BINPOINT_MASK) >> GICH_VMCR_ALIAS_BINPOINT_SHIFT;
vmcrp->bpr = (vmcr & GICH_VMCR_BINPOINT_MASK) >> GICH_VMCR_BINPOINT_SHIFT;
vmcrp->pmr = (vmcr & GICH_VMCR_PRIMASK_MASK) >> GICH_VMCR_PRIMASK_SHIFT;
}
static void vgic_v2_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
{
u32 vmcr;
vmcr = (vmcrp->ctlr << GICH_VMCR_CTRL_SHIFT) & GICH_VMCR_CTRL_MASK;
vmcr |= (vmcrp->abpr << GICH_VMCR_ALIAS_BINPOINT_SHIFT) & GICH_VMCR_ALIAS_BINPOINT_MASK;
vmcr |= (vmcrp->bpr << GICH_VMCR_BINPOINT_SHIFT) & GICH_VMCR_BINPOINT_MASK;
vmcr |= (vmcrp->pmr << GICH_VMCR_PRIMASK_SHIFT) & GICH_VMCR_PRIMASK_MASK;
vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr = vmcr;
}
static void vgic_v2_enable(struct kvm_vcpu *vcpu)
{
/*
* By forcing VMCR to zero, the GIC will restore the binary
* points to their reset values. Anything else resets to zero
* anyway.
*/
vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr = 0;
/* Get the show on the road... */
vcpu->arch.vgic_cpu.vgic_v2.vgic_hcr = GICH_HCR_EN;
}
static const struct vgic_ops vgic_v2_ops = {
.get_lr = vgic_v2_get_lr,
.set_lr = vgic_v2_set_lr,
.sync_lr_elrsr = vgic_v2_sync_lr_elrsr,
.get_elrsr = vgic_v2_get_elrsr,
.get_eisr = vgic_v2_get_eisr,
.get_interrupt_status = vgic_v2_get_interrupt_status,
.enable_underflow = vgic_v2_enable_underflow,
.disable_underflow = vgic_v2_disable_underflow,
.get_vmcr = vgic_v2_get_vmcr,
.set_vmcr = vgic_v2_set_vmcr,
.enable = vgic_v2_enable,
};
static struct vgic_params vgic_v2_params;
/**
* vgic_v2_probe - probe for a GICv2 compatible interrupt controller in DT
* @node: pointer to the DT node
* @ops: address of a pointer to the GICv2 operations
* @params: address of a pointer to HW-specific parameters
*
* Returns 0 if a GICv2 has been found, with the low level operations
* in *ops and the HW parameters in *params. Returns an error code
* otherwise.
*/
int vgic_v2_probe(struct device_node *vgic_node,
const struct vgic_ops **ops,
const struct vgic_params **params)
{
int ret;
struct resource vctrl_res;
struct resource vcpu_res;
struct vgic_params *vgic = &vgic_v2_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;
}
ret = of_address_to_resource(vgic_node, 2, &vctrl_res);
if (ret) {
kvm_err("Cannot obtain GICH resource\n");
goto out;
}
vgic->vctrl_base = of_iomap(vgic_node, 2);
if (!vgic->vctrl_base) {
kvm_err("Cannot ioremap GICH\n");
ret = -ENOMEM;
goto out;
}
vgic->nr_lr = readl_relaxed(vgic->vctrl_base + GICH_VTR);
vgic->nr_lr = (vgic->nr_lr & 0x3f) + 1;
ret = create_hyp_io_mappings(vgic->vctrl_base,
vgic->vctrl_base + resource_size(&vctrl_res),
vctrl_res.start);
if (ret) {
kvm_err("Cannot map VCTRL into hyp\n");
goto out_unmap;
}
if (of_address_to_resource(vgic_node, 3, &vcpu_res)) {
kvm_err("Cannot obtain GICV resource\n");
ret = -ENXIO;
goto out_unmap;
}
if (!PAGE_ALIGNED(vcpu_res.start)) {
kvm_err("GICV physical address 0x%llx not page aligned\n",
(unsigned long long)vcpu_res.start);
ret = -ENXIO;
goto out_unmap;
}
if (!PAGE_ALIGNED(resource_size(&vcpu_res))) {
kvm_err("GICV size 0x%llx not a multiple of page size 0x%lx\n",
(unsigned long long)resource_size(&vcpu_res),
PAGE_SIZE);
ret = -ENXIO;
goto out_unmap;
}
vgic->can_emulate_gicv2 = true;
kvm_register_device_ops(&kvm_arm_vgic_v2_ops, KVM_DEV_TYPE_ARM_VGIC_V2);
vgic->vcpu_base = vcpu_res.start;
kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
vctrl_res.start, vgic->maint_irq);
vgic->type = VGIC_V2;
vgic->max_gic_vcpus = VGIC_V2_MAX_CPUS;
*ops = &vgic_v2_ops;
*params = vgic;
goto out;
out_unmap:
iounmap(vgic->vctrl_base);
out:
of_node_put(vgic_node);
return ret;
}