/*
* Copyright (C) 2015, 2016 ARM Ltd.
*
* 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.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <kvm/arm_vgic.h>
#include <asm/kvm_mmu.h>
#include "vgic.h"
/*
* Call this function to convert a u64 value to an unsigned long * bitmask
* in a way that works on both 32-bit and 64-bit LE and BE platforms.
*
* Warning: Calling this function may modify *val.
*/
static unsigned long *u64_to_bitmask(u64 *val)
{
#if defined(CONFIG_CPU_BIG_ENDIAN) && BITS_PER_LONG == 32
*val = (*val >> 32) | (*val << 32);
#endif
return (unsigned long *)val;
}
void vgic_v2_process_maintenance(struct kvm_vcpu *vcpu)
{
struct vgic_v2_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v2;
if (cpuif->vgic_misr & GICH_MISR_EOI) {
u64 eisr = cpuif->vgic_eisr;
unsigned long *eisr_bmap = u64_to_bitmask(&eisr);
int lr;
for_each_set_bit(lr, eisr_bmap, kvm_vgic_global_state.nr_lr) {
u32 intid = cpuif->vgic_lr[lr] & GICH_LR_VIRTUALID;
WARN_ON(cpuif->vgic_lr[lr] & GICH_LR_STATE);
kvm_notify_acked_irq(vcpu->kvm, 0,
intid - VGIC_NR_PRIVATE_IRQS);
}
}
/* check and disable underflow maintenance IRQ */
cpuif->vgic_hcr &= ~GICH_HCR_UIE;
/*
* 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;
}
void vgic_v2_set_underflow(struct kvm_vcpu *vcpu)
{
struct vgic_v2_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v2;
cpuif->vgic_hcr |= GICH_HCR_UIE;
}
/*
* transfer the content of the LRs back into the corresponding ap_list:
* - active bit is transferred as is
* - pending bit is
* - transferred as is in case of edge sensitive IRQs
* - set to the line-level (resample time) for level sensitive IRQs
*/
void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu)
{
struct vgic_v2_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v2;
int lr;
for (lr = 0; lr < vcpu->arch.vgic_cpu.used_lrs; lr++) {
u32 val = cpuif->vgic_lr[lr];
u32 intid = val & GICH_LR_VIRTUALID;
struct vgic_irq *irq;
irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
spin_lock(&irq->irq_lock);
/* Always preserve the active bit */
irq->active = !!(val & GICH_LR_ACTIVE_BIT);
/* Edge is the only case where we preserve the pending bit */
if (irq->config == VGIC_CONFIG_EDGE &&
(val & GICH_LR_PENDING_BIT)) {
irq->pending = true;
if (vgic_irq_is_sgi(intid)) {
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.
* Always regenerate the pending state.
*/
if (irq->config == VGIC_CONFIG_LEVEL) {
if (!(val & GICH_LR_PENDING_BIT))
irq->soft_pending = false;
irq->pending = irq->line_level || irq->soft_pending;
}
spin_unlock(&irq->irq_lock);
vgic_put_irq(vcpu->kvm, irq);
}
}
/*
* Populates the particular LR with the state of a given IRQ:
* - for an edge sensitive IRQ the pending state is cleared in struct vgic_irq
* - for a level sensitive IRQ the pending state value is unchanged;
* it is dictated directly by the input level
*
* If @irq describes an SGI with multiple sources, we choose the
* lowest-numbered source VCPU and clear that bit in the source bitmap.
*
* The irq_lock must be held by the caller.
*/
void vgic_v2_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
{
u32 val = irq->intid;
if (irq->pending) {
val |= GICH_LR_PENDING_BIT;
if (irq->config == VGIC_CONFIG_EDGE)
irq->pending = false;
if (vgic_irq_is_sgi(irq->intid)) {
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 |= GICH_LR_ACTIVE_BIT;
if (irq->hw) {
val |= GICH_LR_HW;
val |= irq->hwintid << GICH_LR_PHYSID_CPUID_SHIFT;
} else {
if (irq->config == VGIC_CONFIG_LEVEL)
val |= GICH_LR_EOI;
}
/* The GICv2 LR only holds five bits of priority. */
val |= (irq->priority >> 3) << GICH_LR_PRIORITY_SHIFT;
vcpu->arch.vgic_cpu.vgic_v2.vgic_lr[lr] = val;
}
void vgic_v2_clear_lr(struct kvm_vcpu *vcpu, int lr)
{
vcpu->arch.vgic_cpu.vgic_v2.vgic_lr[lr] = 0;
}
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;
}
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;
}
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;
vcpu->arch.vgic_cpu.vgic_v2.vgic_elrsr = ~0;
/* Get the show on the road... */
vcpu->arch.vgic_cpu.vgic_v2.vgic_hcr = GICH_HCR_EN;
}
/* check for overlapping regions and for regions crossing the end of memory */
static bool vgic_v2_check_base(gpa_t dist_base, gpa_t cpu_base)
{
if (dist_base + KVM_VGIC_V2_DIST_SIZE < dist_base)
return false;
if (cpu_base + KVM_VGIC_V2_CPU_SIZE < cpu_base)
return false;
if (dist_base + KVM_VGIC_V2_DIST_SIZE <= cpu_base)
return true;
if (cpu_base + KVM_VGIC_V2_CPU_SIZE <= dist_base)
return true;
return false;
}
int vgic_v2_map_resources(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
int ret = 0;
if (vgic_ready(kvm))
goto out;
if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) ||
IS_VGIC_ADDR_UNDEF(dist->vgic_cpu_base)) {
kvm_err("Need to set vgic cpu and dist addresses first\n");
ret = -ENXIO;
goto out;
}
if (!vgic_v2_check_base(dist->vgic_dist_base, dist->vgic_cpu_base)) {
kvm_err("VGIC CPU and dist frames overlap\n");
ret = -EINVAL;
goto out;
}
/*
* Initialize the vgic if this hasn't already been done on demand by
* accessing the vgic state from userspace.
*/
ret = vgic_init(kvm);
if (ret) {
kvm_err("Unable to initialize VGIC dynamic data structures\n");
goto out;
}
ret = vgic_register_dist_iodev(kvm, dist->vgic_dist_base, VGIC_V2);
if (ret) {
kvm_err("Unable to register VGIC MMIO regions\n");
goto out;
}
if (!static_branch_unlikely(&vgic_v2_cpuif_trap)) {
ret = kvm_phys_addr_ioremap(kvm, dist->vgic_cpu_base,
kvm_vgic_global_state.vcpu_base,
KVM_VGIC_V2_CPU_SIZE, true);
if (ret) {
kvm_err("Unable to remap VGIC CPU to VCPU\n");
goto out;
}
}
dist->ready = true;
out:
if (ret)
kvm_vgic_destroy(kvm);
return ret;
}
DEFINE_STATIC_KEY_FALSE(vgic_v2_cpuif_trap);
/**
* vgic_v2_probe - probe for a GICv2 compatible interrupt controller in DT
* @node: pointer to the DT node
*
* Returns 0 if a GICv2 has been found, returns an error code otherwise
*/
int vgic_v2_probe(const struct gic_kvm_info *info)
{
int ret;
u32 vtr;
if (!info->vctrl.start) {
kvm_err("GICH not present in the firmware table\n");
return -ENXIO;
}
if (!PAGE_ALIGNED(info->vcpu.start) ||
!PAGE_ALIGNED(resource_size(&info->vcpu))) {
kvm_info("GICV region size/alignment is unsafe, using trapping (reduced performance)\n");
kvm_vgic_global_state.vcpu_base_va = ioremap(info->vcpu.start,
resource_size(&info->vcpu));
if (!kvm_vgic_global_state.vcpu_base_va) {
kvm_err("Cannot ioremap GICV\n");
return -ENOMEM;
}
ret = create_hyp_io_mappings(kvm_vgic_global_state.vcpu_base_va,
kvm_vgic_global_state.vcpu_base_va + resource_size(&info->vcpu),
info->vcpu.start);
if (ret) {
kvm_err("Cannot map GICV into hyp\n");
goto out;
}
static_branch_enable(&vgic_v2_cpuif_trap);
}
kvm_vgic_global_state.vctrl_base = ioremap(info->vctrl.start,
resource_size(&info->vctrl));
if (!kvm_vgic_global_state.vctrl_base) {
kvm_err("Cannot ioremap GICH\n");
ret = -ENOMEM;
goto out;
}
vtr = readl_relaxed(kvm_vgic_global_state.vctrl_base + GICH_VTR);
kvm_vgic_global_state.nr_lr = (vtr & 0x3f) + 1;
ret = create_hyp_io_mappings(kvm_vgic_global_state.vctrl_base,
kvm_vgic_global_state.vctrl_base +
resource_size(&info->vctrl),
info->vctrl.start);
if (ret) {
kvm_err("Cannot map VCTRL into hyp\n");
goto out;
}
ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
if (ret) {
kvm_err("Cannot register GICv2 KVM device\n");
goto out;
}
kvm_vgic_global_state.can_emulate_gicv2 = true;
kvm_vgic_global_state.vcpu_base = info->vcpu.start;
kvm_vgic_global_state.type = VGIC_V2;
kvm_vgic_global_state.max_gic_vcpus = VGIC_V2_MAX_CPUS;
kvm_info("vgic-v2@%llx\n", info->vctrl.start);
return 0;
out:
if (kvm_vgic_global_state.vctrl_base)
iounmap(kvm_vgic_global_state.vctrl_base);
if (kvm_vgic_global_state.vcpu_base_va)
iounmap(kvm_vgic_global_state.vcpu_base_va);
return ret;
}
