]> git.kernelconcepts.de Git - karo-tx-linux.git/blobdiff - virt/kvm/arm/vgic.c
ARM: KVM: move GIC/timer code to a common location
[karo-tx-linux.git] / virt / kvm / arm / vgic.c
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
new file mode 100644 (file)
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+/*
+ * 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/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>
+
+/*
+ * How the whole thing works (courtesy of Christoffer Dall):
+ *
+ * - At any time, the dist->irq_pending_on_cpu is the oracle that knows if
+ *   something is pending
+ * - VGIC pending interrupts are stored on the vgic.irq_state vgic
+ *   bitmap (this bitmap is updated by both user land ioctls and guest
+ *   mmio ops, and other in-kernel peripherals such as the
+ *   arch. timers) and indicate the 'wire' state.
+ * - Every time the bitmap changes, the irq_pending_on_cpu oracle is
+ *   recalculated
+ * - To calculate the oracle, we need info for each cpu from
+ *   compute_pending_for_cpu, which considers:
+ *   - PPI: dist->irq_state & dist->irq_enable
+ *   - SPI: dist->irq_state & dist->irq_enable & dist->irq_spi_target
+ *   - irq_spi_target is a 'formatted' version of the GICD_ICFGR
+ *     registers, stored on each vcpu. We only keep one bit of
+ *     information per interrupt, making sure that only one vcpu can
+ *     accept the interrupt.
+ * - The same is true when injecting an interrupt, except that we only
+ *   consider a single interrupt at a time. The irq_spi_cpu array
+ *   contains the target CPU for each SPI.
+ *
+ * The handling of level interrupts adds some extra complexity. We
+ * need to track when the interrupt has been EOIed, so we can sample
+ * the 'line' again. This is achieved as such:
+ *
+ * - When a level interrupt is moved onto a vcpu, the corresponding
+ *   bit in irq_active is set. As long as this bit is set, the line
+ *   will be ignored for further interrupts. The interrupt is injected
+ *   into the vcpu with the GICH_LR_EOI bit set (generate a
+ *   maintenance interrupt on EOI).
+ * - When the interrupt is EOIed, the maintenance interrupt fires,
+ *   and clears the corresponding bit in irq_active. This allow the
+ *   interrupt line to be sampled again.
+ */
+
+#define VGIC_ADDR_UNDEF                (-1)
+#define IS_VGIC_ADDR_UNDEF(_x)  ((_x) == VGIC_ADDR_UNDEF)
+
+/* Physical address of vgic virtual cpu interface */
+static phys_addr_t vgic_vcpu_base;
+
+/* Virtual control interface base address */
+static void __iomem *vgic_vctrl_base;
+
+static struct device_node *vgic_node;
+
+#define ACCESS_READ_VALUE      (1 << 0)
+#define ACCESS_READ_RAZ                (0 << 0)
+#define ACCESS_READ_MASK(x)    ((x) & (1 << 0))
+#define ACCESS_WRITE_IGNORED   (0 << 1)
+#define ACCESS_WRITE_SETBIT    (1 << 1)
+#define ACCESS_WRITE_CLEARBIT  (2 << 1)
+#define ACCESS_WRITE_VALUE     (3 << 1)
+#define ACCESS_WRITE_MASK(x)   ((x) & (3 << 1))
+
+static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu);
+static void vgic_update_state(struct kvm *kvm);
+static void vgic_kick_vcpus(struct kvm *kvm);
+static void vgic_dispatch_sgi(struct kvm_vcpu *vcpu, u32 reg);
+static u32 vgic_nr_lr;
+
+static unsigned int vgic_maint_irq;
+
+static u32 *vgic_bitmap_get_reg(struct vgic_bitmap *x,
+                               int cpuid, u32 offset)
+{
+       offset >>= 2;
+       if (!offset)
+               return x->percpu[cpuid].reg;
+       else
+               return x->shared.reg + offset - 1;
+}
+
+static int vgic_bitmap_get_irq_val(struct vgic_bitmap *x,
+                                  int cpuid, int irq)
+{
+       if (irq < VGIC_NR_PRIVATE_IRQS)
+               return test_bit(irq, x->percpu[cpuid].reg_ul);
+
+       return test_bit(irq - VGIC_NR_PRIVATE_IRQS, x->shared.reg_ul);
+}
+
+static void vgic_bitmap_set_irq_val(struct vgic_bitmap *x, int cpuid,
+                                   int irq, int val)
+{
+       unsigned long *reg;
+
+       if (irq < VGIC_NR_PRIVATE_IRQS) {
+               reg = x->percpu[cpuid].reg_ul;
+       } else {
+               reg =  x->shared.reg_ul;
+               irq -= VGIC_NR_PRIVATE_IRQS;
+       }
+
+       if (val)
+               set_bit(irq, reg);
+       else
+               clear_bit(irq, reg);
+}
+
+static unsigned long *vgic_bitmap_get_cpu_map(struct vgic_bitmap *x, int cpuid)
+{
+       if (unlikely(cpuid >= VGIC_MAX_CPUS))
+               return NULL;
+       return x->percpu[cpuid].reg_ul;
+}
+
+static unsigned long *vgic_bitmap_get_shared_map(struct vgic_bitmap *x)
+{
+       return x->shared.reg_ul;
+}
+
+static u32 *vgic_bytemap_get_reg(struct vgic_bytemap *x, int cpuid, u32 offset)
+{
+       offset >>= 2;
+       BUG_ON(offset > (VGIC_NR_IRQS / 4));
+       if (offset < 4)
+               return x->percpu[cpuid] + offset;
+       else
+               return x->shared + offset - 8;
+}
+
+#define VGIC_CFG_LEVEL 0
+#define VGIC_CFG_EDGE  1
+
+static bool vgic_irq_is_edge(struct kvm_vcpu *vcpu, int irq)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+       int irq_val;
+
+       irq_val = vgic_bitmap_get_irq_val(&dist->irq_cfg, vcpu->vcpu_id, irq);
+       return irq_val == VGIC_CFG_EDGE;
+}
+
+static int vgic_irq_is_enabled(struct kvm_vcpu *vcpu, int irq)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+       return vgic_bitmap_get_irq_val(&dist->irq_enabled, vcpu->vcpu_id, irq);
+}
+
+static int vgic_irq_is_active(struct kvm_vcpu *vcpu, int irq)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+       return vgic_bitmap_get_irq_val(&dist->irq_active, vcpu->vcpu_id, irq);
+}
+
+static void vgic_irq_set_active(struct kvm_vcpu *vcpu, int irq)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+       vgic_bitmap_set_irq_val(&dist->irq_active, vcpu->vcpu_id, irq, 1);
+}
+
+static void vgic_irq_clear_active(struct kvm_vcpu *vcpu, int irq)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+       vgic_bitmap_set_irq_val(&dist->irq_active, vcpu->vcpu_id, irq, 0);
+}
+
+static int vgic_dist_irq_is_pending(struct kvm_vcpu *vcpu, int irq)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+       return vgic_bitmap_get_irq_val(&dist->irq_state, vcpu->vcpu_id, irq);
+}
+
+static void vgic_dist_irq_set(struct kvm_vcpu *vcpu, int irq)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+       vgic_bitmap_set_irq_val(&dist->irq_state, vcpu->vcpu_id, irq, 1);
+}
+
+static void vgic_dist_irq_clear(struct kvm_vcpu *vcpu, int irq)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+       vgic_bitmap_set_irq_val(&dist->irq_state, vcpu->vcpu_id, irq, 0);
+}
+
+static void vgic_cpu_irq_set(struct kvm_vcpu *vcpu, int irq)
+{
+       if (irq < VGIC_NR_PRIVATE_IRQS)
+               set_bit(irq, vcpu->arch.vgic_cpu.pending_percpu);
+       else
+               set_bit(irq - VGIC_NR_PRIVATE_IRQS,
+                       vcpu->arch.vgic_cpu.pending_shared);
+}
+
+static void vgic_cpu_irq_clear(struct kvm_vcpu *vcpu, int irq)
+{
+       if (irq < VGIC_NR_PRIVATE_IRQS)
+               clear_bit(irq, vcpu->arch.vgic_cpu.pending_percpu);
+       else
+               clear_bit(irq - VGIC_NR_PRIVATE_IRQS,
+                         vcpu->arch.vgic_cpu.pending_shared);
+}
+
+static u32 mmio_data_read(struct kvm_exit_mmio *mmio, u32 mask)
+{
+       return *((u32 *)mmio->data) & mask;
+}
+
+static void mmio_data_write(struct kvm_exit_mmio *mmio, u32 mask, u32 value)
+{
+       *((u32 *)mmio->data) = value & mask;
+}
+
+/**
+ * vgic_reg_access - access vgic register
+ * @mmio:   pointer to the data describing the mmio access
+ * @reg:    pointer to the virtual backing of vgic distributor data
+ * @offset: least significant 2 bits used for word offset
+ * @mode:   ACCESS_ mode (see defines above)
+ *
+ * Helper to make vgic register access easier using one of the access
+ * modes defined for vgic register access
+ * (read,raz,write-ignored,setbit,clearbit,write)
+ */
+static void vgic_reg_access(struct kvm_exit_mmio *mmio, u32 *reg,
+                           phys_addr_t offset, int mode)
+{
+       int word_offset = (offset & 3) * 8;
+       u32 mask = (1UL << (mmio->len * 8)) - 1;
+       u32 regval;
+
+       /*
+        * Any alignment fault should have been delivered to the guest
+        * directly (ARM ARM B3.12.7 "Prioritization of aborts").
+        */
+
+       if (reg) {
+               regval = *reg;
+       } else {
+               BUG_ON(mode != (ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED));
+               regval = 0;
+       }
+
+       if (mmio->is_write) {
+               u32 data = mmio_data_read(mmio, mask) << word_offset;
+               switch (ACCESS_WRITE_MASK(mode)) {
+               case ACCESS_WRITE_IGNORED:
+                       return;
+
+               case ACCESS_WRITE_SETBIT:
+                       regval |= data;
+                       break;
+
+               case ACCESS_WRITE_CLEARBIT:
+                       regval &= ~data;
+                       break;
+
+               case ACCESS_WRITE_VALUE:
+                       regval = (regval & ~(mask << word_offset)) | data;
+                       break;
+               }
+               *reg = regval;
+       } else {
+               switch (ACCESS_READ_MASK(mode)) {
+               case ACCESS_READ_RAZ:
+                       regval = 0;
+                       /* fall through */
+
+               case ACCESS_READ_VALUE:
+                       mmio_data_write(mmio, mask, regval >> word_offset);
+               }
+       }
+}
+
+static bool handle_mmio_misc(struct kvm_vcpu *vcpu,
+                            struct kvm_exit_mmio *mmio, phys_addr_t offset)
+{
+       u32 reg;
+       u32 word_offset = offset & 3;
+
+       switch (offset & ~3) {
+       case 0:                 /* CTLR */
+               reg = vcpu->kvm->arch.vgic.enabled;
+               vgic_reg_access(mmio, &reg, word_offset,
+                               ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
+               if (mmio->is_write) {
+                       vcpu->kvm->arch.vgic.enabled = reg & 1;
+                       vgic_update_state(vcpu->kvm);
+                       return true;
+               }
+               break;
+
+       case 4:                 /* TYPER */
+               reg  = (atomic_read(&vcpu->kvm->online_vcpus) - 1) << 5;
+               reg |= (VGIC_NR_IRQS >> 5) - 1;
+               vgic_reg_access(mmio, &reg, word_offset,
+                               ACCESS_READ_VALUE | ACCESS_WRITE_IGNORED);
+               break;
+
+       case 8:                 /* IIDR */
+               reg = 0x4B00043B;
+               vgic_reg_access(mmio, &reg, word_offset,
+                               ACCESS_READ_VALUE | ACCESS_WRITE_IGNORED);
+               break;
+       }
+
+       return false;
+}
+
+static bool handle_mmio_raz_wi(struct kvm_vcpu *vcpu,
+                              struct kvm_exit_mmio *mmio, phys_addr_t offset)
+{
+       vgic_reg_access(mmio, NULL, offset,
+                       ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED);
+       return false;
+}
+
+static bool handle_mmio_set_enable_reg(struct kvm_vcpu *vcpu,
+                                      struct kvm_exit_mmio *mmio,
+                                      phys_addr_t offset)
+{
+       u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_enabled,
+                                      vcpu->vcpu_id, offset);
+       vgic_reg_access(mmio, reg, offset,
+                       ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT);
+       if (mmio->is_write) {
+               vgic_update_state(vcpu->kvm);
+               return true;
+       }
+
+       return false;
+}
+
+static bool handle_mmio_clear_enable_reg(struct kvm_vcpu *vcpu,
+                                        struct kvm_exit_mmio *mmio,
+                                        phys_addr_t offset)
+{
+       u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_enabled,
+                                      vcpu->vcpu_id, offset);
+       vgic_reg_access(mmio, reg, offset,
+                       ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT);
+       if (mmio->is_write) {
+               if (offset < 4) /* Force SGI enabled */
+                       *reg |= 0xffff;
+               vgic_retire_disabled_irqs(vcpu);
+               vgic_update_state(vcpu->kvm);
+               return true;
+       }
+
+       return false;
+}
+
+static bool handle_mmio_set_pending_reg(struct kvm_vcpu *vcpu,
+                                       struct kvm_exit_mmio *mmio,
+                                       phys_addr_t offset)
+{
+       u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_state,
+                                      vcpu->vcpu_id, offset);
+       vgic_reg_access(mmio, reg, offset,
+                       ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT);
+       if (mmio->is_write) {
+               vgic_update_state(vcpu->kvm);
+               return true;
+       }
+
+       return false;
+}
+
+static bool handle_mmio_clear_pending_reg(struct kvm_vcpu *vcpu,
+                                         struct kvm_exit_mmio *mmio,
+                                         phys_addr_t offset)
+{
+       u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_state,
+                                      vcpu->vcpu_id, offset);
+       vgic_reg_access(mmio, reg, offset,
+                       ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT);
+       if (mmio->is_write) {
+               vgic_update_state(vcpu->kvm);
+               return true;
+       }
+
+       return false;
+}
+
+static bool handle_mmio_priority_reg(struct kvm_vcpu *vcpu,
+                                    struct kvm_exit_mmio *mmio,
+                                    phys_addr_t offset)
+{
+       u32 *reg = vgic_bytemap_get_reg(&vcpu->kvm->arch.vgic.irq_priority,
+                                       vcpu->vcpu_id, offset);
+       vgic_reg_access(mmio, reg, offset,
+                       ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
+       return false;
+}
+
+#define GICD_ITARGETSR_SIZE    32
+#define GICD_CPUTARGETS_BITS   8
+#define GICD_IRQS_PER_ITARGETSR        (GICD_ITARGETSR_SIZE / GICD_CPUTARGETS_BITS)
+static u32 vgic_get_target_reg(struct kvm *kvm, int irq)
+{
+       struct vgic_dist *dist = &kvm->arch.vgic;
+       struct kvm_vcpu *vcpu;
+       int i, c;
+       unsigned long *bmap;
+       u32 val = 0;
+
+       irq -= VGIC_NR_PRIVATE_IRQS;
+
+       kvm_for_each_vcpu(c, vcpu, kvm) {
+               bmap = vgic_bitmap_get_shared_map(&dist->irq_spi_target[c]);
+               for (i = 0; i < GICD_IRQS_PER_ITARGETSR; i++)
+                       if (test_bit(irq + i, bmap))
+                               val |= 1 << (c + i * 8);
+       }
+
+       return val;
+}
+
+static void vgic_set_target_reg(struct kvm *kvm, u32 val, int irq)
+{
+       struct vgic_dist *dist = &kvm->arch.vgic;
+       struct kvm_vcpu *vcpu;
+       int i, c;
+       unsigned long *bmap;
+       u32 target;
+
+       irq -= VGIC_NR_PRIVATE_IRQS;
+
+       /*
+        * Pick the LSB in each byte. This ensures we target exactly
+        * one vcpu per IRQ. If the byte is null, assume we target
+        * CPU0.
+        */
+       for (i = 0; i < GICD_IRQS_PER_ITARGETSR; i++) {
+               int shift = i * GICD_CPUTARGETS_BITS;
+               target = ffs((val >> shift) & 0xffU);
+               target = target ? (target - 1) : 0;
+               dist->irq_spi_cpu[irq + i] = target;
+               kvm_for_each_vcpu(c, vcpu, kvm) {
+                       bmap = vgic_bitmap_get_shared_map(&dist->irq_spi_target[c]);
+                       if (c == target)
+                               set_bit(irq + i, bmap);
+                       else
+                               clear_bit(irq + i, bmap);
+               }
+       }
+}
+
+static bool handle_mmio_target_reg(struct kvm_vcpu *vcpu,
+                                  struct kvm_exit_mmio *mmio,
+                                  phys_addr_t offset)
+{
+       u32 reg;
+
+       /* We treat the banked interrupts targets as read-only */
+       if (offset < 32) {
+               u32 roreg = 1 << vcpu->vcpu_id;
+               roreg |= roreg << 8;
+               roreg |= roreg << 16;
+
+               vgic_reg_access(mmio, &roreg, offset,
+                               ACCESS_READ_VALUE | ACCESS_WRITE_IGNORED);
+               return false;
+       }
+
+       reg = vgic_get_target_reg(vcpu->kvm, offset & ~3U);
+       vgic_reg_access(mmio, &reg, offset,
+                       ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
+       if (mmio->is_write) {
+               vgic_set_target_reg(vcpu->kvm, reg, offset & ~3U);
+               vgic_update_state(vcpu->kvm);
+               return true;
+       }
+
+       return false;
+}
+
+static u32 vgic_cfg_expand(u16 val)
+{
+       u32 res = 0;
+       int i;
+
+       /*
+        * Turn a 16bit value like abcd...mnop into a 32bit word
+        * a0b0c0d0...m0n0o0p0, which is what the HW cfg register is.
+        */
+       for (i = 0; i < 16; i++)
+               res |= ((val >> i) & VGIC_CFG_EDGE) << (2 * i + 1);
+
+       return res;
+}
+
+static u16 vgic_cfg_compress(u32 val)
+{
+       u16 res = 0;
+       int i;
+
+       /*
+        * Turn a 32bit word a0b0c0d0...m0n0o0p0 into 16bit value like
+        * abcd...mnop which is what we really care about.
+        */
+       for (i = 0; i < 16; i++)
+               res |= ((val >> (i * 2 + 1)) & VGIC_CFG_EDGE) << i;
+
+       return res;
+}
+
+/*
+ * The distributor uses 2 bits per IRQ for the CFG register, but the
+ * LSB is always 0. As such, we only keep the upper bit, and use the
+ * two above functions to compress/expand the bits
+ */
+static bool handle_mmio_cfg_reg(struct kvm_vcpu *vcpu,
+                               struct kvm_exit_mmio *mmio, phys_addr_t offset)
+{
+       u32 val;
+       u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_cfg,
+                                      vcpu->vcpu_id, offset >> 1);
+       if (offset & 2)
+               val = *reg >> 16;
+       else
+               val = *reg & 0xffff;
+
+       val = vgic_cfg_expand(val);
+       vgic_reg_access(mmio, &val, offset,
+                       ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
+       if (mmio->is_write) {
+               if (offset < 4) {
+                       *reg = ~0U; /* Force PPIs/SGIs to 1 */
+                       return false;
+               }
+
+               val = vgic_cfg_compress(val);
+               if (offset & 2) {
+                       *reg &= 0xffff;
+                       *reg |= val << 16;
+               } else {
+                       *reg &= 0xffff << 16;
+                       *reg |= val;
+               }
+       }
+
+       return false;
+}
+
+static bool handle_mmio_sgi_reg(struct kvm_vcpu *vcpu,
+                               struct kvm_exit_mmio *mmio, phys_addr_t offset)
+{
+       u32 reg;
+       vgic_reg_access(mmio, &reg, offset,
+                       ACCESS_READ_RAZ | ACCESS_WRITE_VALUE);
+       if (mmio->is_write) {
+               vgic_dispatch_sgi(vcpu, reg);
+               vgic_update_state(vcpu->kvm);
+               return true;
+       }
+
+       return false;
+}
+
+/*
+ * I would have liked to use the kvm_bus_io_*() API instead, but it
+ * cannot cope with banked registers (only the VM pointer is passed
+ * around, and we need the vcpu). One of these days, someone please
+ * fix it!
+ */
+struct mmio_range {
+       phys_addr_t base;
+       unsigned long len;
+       bool (*handle_mmio)(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
+                           phys_addr_t offset);
+};
+
+static const struct mmio_range vgic_ranges[] = {
+       {
+               .base           = GIC_DIST_CTRL,
+               .len            = 12,
+               .handle_mmio    = handle_mmio_misc,
+       },
+       {
+               .base           = GIC_DIST_IGROUP,
+               .len            = VGIC_NR_IRQS / 8,
+               .handle_mmio    = handle_mmio_raz_wi,
+       },
+       {
+               .base           = GIC_DIST_ENABLE_SET,
+               .len            = VGIC_NR_IRQS / 8,
+               .handle_mmio    = handle_mmio_set_enable_reg,
+       },
+       {
+               .base           = GIC_DIST_ENABLE_CLEAR,
+               .len            = VGIC_NR_IRQS / 8,
+               .handle_mmio    = handle_mmio_clear_enable_reg,
+       },
+       {
+               .base           = GIC_DIST_PENDING_SET,
+               .len            = VGIC_NR_IRQS / 8,
+               .handle_mmio    = handle_mmio_set_pending_reg,
+       },
+       {
+               .base           = GIC_DIST_PENDING_CLEAR,
+               .len            = VGIC_NR_IRQS / 8,
+               .handle_mmio    = handle_mmio_clear_pending_reg,
+       },
+       {
+               .base           = GIC_DIST_ACTIVE_SET,
+               .len            = VGIC_NR_IRQS / 8,
+               .handle_mmio    = handle_mmio_raz_wi,
+       },
+       {
+               .base           = GIC_DIST_ACTIVE_CLEAR,
+               .len            = VGIC_NR_IRQS / 8,
+               .handle_mmio    = handle_mmio_raz_wi,
+       },
+       {
+               .base           = GIC_DIST_PRI,
+               .len            = VGIC_NR_IRQS,
+               .handle_mmio    = handle_mmio_priority_reg,
+       },
+       {
+               .base           = GIC_DIST_TARGET,
+               .len            = VGIC_NR_IRQS,
+               .handle_mmio    = handle_mmio_target_reg,
+       },
+       {
+               .base           = GIC_DIST_CONFIG,
+               .len            = VGIC_NR_IRQS / 4,
+               .handle_mmio    = handle_mmio_cfg_reg,
+       },
+       {
+               .base           = GIC_DIST_SOFTINT,
+               .len            = 4,
+               .handle_mmio    = handle_mmio_sgi_reg,
+       },
+       {}
+};
+
+static const
+struct mmio_range *find_matching_range(const struct mmio_range *ranges,
+                                      struct kvm_exit_mmio *mmio,
+                                      phys_addr_t base)
+{
+       const struct mmio_range *r = ranges;
+       phys_addr_t addr = mmio->phys_addr - base;
+
+       while (r->len) {
+               if (addr >= r->base &&
+                   (addr + mmio->len) <= (r->base + r->len))
+                       return r;
+               r++;
+       }
+
+       return NULL;
+}
+
+/**
+ * vgic_handle_mmio - handle an in-kernel MMIO access
+ * @vcpu:      pointer to the vcpu performing the access
+ * @run:       pointer to the kvm_run structure
+ * @mmio:      pointer to the data describing the access
+ *
+ * returns true if the MMIO access has been performed in kernel space,
+ * and false if it needs to be emulated in user space.
+ */
+bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run,
+                     struct kvm_exit_mmio *mmio)
+{
+       const struct mmio_range *range;
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+       unsigned long base = dist->vgic_dist_base;
+       bool updated_state;
+       unsigned long offset;
+
+       if (!irqchip_in_kernel(vcpu->kvm) ||
+           mmio->phys_addr < base ||
+           (mmio->phys_addr + mmio->len) > (base + KVM_VGIC_V2_DIST_SIZE))
+               return false;
+
+       /* We don't support ldrd / strd or ldm / stm to the emulated vgic */
+       if (mmio->len > 4) {
+               kvm_inject_dabt(vcpu, mmio->phys_addr);
+               return true;
+       }
+
+       range = find_matching_range(vgic_ranges, mmio, base);
+       if (unlikely(!range || !range->handle_mmio)) {
+               pr_warn("Unhandled access %d %08llx %d\n",
+                       mmio->is_write, mmio->phys_addr, mmio->len);
+               return false;
+       }
+
+       spin_lock(&vcpu->kvm->arch.vgic.lock);
+       offset = mmio->phys_addr - range->base - base;
+       updated_state = range->handle_mmio(vcpu, mmio, offset);
+       spin_unlock(&vcpu->kvm->arch.vgic.lock);
+       kvm_prepare_mmio(run, mmio);
+       kvm_handle_mmio_return(vcpu, run);
+
+       if (updated_state)
+               vgic_kick_vcpus(vcpu->kvm);
+
+       return true;
+}
+
+static void vgic_dispatch_sgi(struct kvm_vcpu *vcpu, u32 reg)
+{
+       struct kvm *kvm = vcpu->kvm;
+       struct vgic_dist *dist = &kvm->arch.vgic;
+       int nrcpus = atomic_read(&kvm->online_vcpus);
+       u8 target_cpus;
+       int sgi, mode, c, vcpu_id;
+
+       vcpu_id = vcpu->vcpu_id;
+
+       sgi = reg & 0xf;
+       target_cpus = (reg >> 16) & 0xff;
+       mode = (reg >> 24) & 3;
+
+       switch (mode) {
+       case 0:
+               if (!target_cpus)
+                       return;
+
+       case 1:
+               target_cpus = ((1 << nrcpus) - 1) & ~(1 << vcpu_id) & 0xff;
+               break;
+
+       case 2:
+               target_cpus = 1 << vcpu_id;
+               break;
+       }
+
+       kvm_for_each_vcpu(c, vcpu, kvm) {
+               if (target_cpus & 1) {
+                       /* Flag the SGI as pending */
+                       vgic_dist_irq_set(vcpu, sgi);
+                       dist->irq_sgi_sources[c][sgi] |= 1 << vcpu_id;
+                       kvm_debug("SGI%d from CPU%d to CPU%d\n", sgi, vcpu_id, c);
+               }
+
+               target_cpus >>= 1;
+       }
+}
+
+static int compute_pending_for_cpu(struct kvm_vcpu *vcpu)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+       unsigned long *pending, *enabled, *pend_percpu, *pend_shared;
+       unsigned long pending_private, pending_shared;
+       int vcpu_id;
+
+       vcpu_id = vcpu->vcpu_id;
+       pend_percpu = vcpu->arch.vgic_cpu.pending_percpu;
+       pend_shared = vcpu->arch.vgic_cpu.pending_shared;
+
+       pending = vgic_bitmap_get_cpu_map(&dist->irq_state, vcpu_id);
+       enabled = vgic_bitmap_get_cpu_map(&dist->irq_enabled, vcpu_id);
+       bitmap_and(pend_percpu, pending, enabled, VGIC_NR_PRIVATE_IRQS);
+
+       pending = vgic_bitmap_get_shared_map(&dist->irq_state);
+       enabled = vgic_bitmap_get_shared_map(&dist->irq_enabled);
+       bitmap_and(pend_shared, pending, enabled, VGIC_NR_SHARED_IRQS);
+       bitmap_and(pend_shared, pend_shared,
+                  vgic_bitmap_get_shared_map(&dist->irq_spi_target[vcpu_id]),
+                  VGIC_NR_SHARED_IRQS);
+
+       pending_private = find_first_bit(pend_percpu, VGIC_NR_PRIVATE_IRQS);
+       pending_shared = find_first_bit(pend_shared, VGIC_NR_SHARED_IRQS);
+       return (pending_private < VGIC_NR_PRIVATE_IRQS ||
+               pending_shared < VGIC_NR_SHARED_IRQS);
+}
+
+/*
+ * Update the interrupt state and determine which CPUs have pending
+ * interrupts. Must be called with distributor lock held.
+ */
+static void vgic_update_state(struct kvm *kvm)
+{
+       struct vgic_dist *dist = &kvm->arch.vgic;
+       struct kvm_vcpu *vcpu;
+       int c;
+
+       if (!dist->enabled) {
+               set_bit(0, &dist->irq_pending_on_cpu);
+               return;
+       }
+
+       kvm_for_each_vcpu(c, vcpu, kvm) {
+               if (compute_pending_for_cpu(vcpu)) {
+                       pr_debug("CPU%d has pending interrupts\n", c);
+                       set_bit(c, &dist->irq_pending_on_cpu);
+               }
+       }
+}
+
+#define LR_CPUID(lr)   \
+       (((lr) & GICH_LR_PHYSID_CPUID) >> GICH_LR_PHYSID_CPUID_SHIFT)
+#define MK_LR_PEND(src, irq)   \
+       (GICH_LR_PENDING_BIT | ((src) << GICH_LR_PHYSID_CPUID_SHIFT) | (irq))
+
+/*
+ * An interrupt may have been disabled after being made pending on the
+ * CPU interface (the classic case is a timer running while we're
+ * rebooting the guest - the interrupt would kick as soon as the CPU
+ * interface gets enabled, with deadly consequences).
+ *
+ * The solution is to examine already active LRs, and check the
+ * interrupt is still enabled. If not, just retire it.
+ */
+static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu)
+{
+       struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+       int lr;
+
+       for_each_set_bit(lr, vgic_cpu->lr_used, vgic_cpu->nr_lr) {
+               int irq = vgic_cpu->vgic_lr[lr] & GICH_LR_VIRTUALID;
+
+               if (!vgic_irq_is_enabled(vcpu, irq)) {
+                       vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY;
+                       clear_bit(lr, vgic_cpu->lr_used);
+                       vgic_cpu->vgic_lr[lr] &= ~GICH_LR_STATE;
+                       if (vgic_irq_is_active(vcpu, irq))
+                               vgic_irq_clear_active(vcpu, irq);
+               }
+       }
+}
+
+/*
+ * Queue an interrupt to a CPU virtual interface. Return true on success,
+ * or false if it wasn't possible to queue it.
+ */
+static bool vgic_queue_irq(struct kvm_vcpu *vcpu, u8 sgi_source_id, int irq)
+{
+       struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+       int lr;
+
+       /* Sanitize the input... */
+       BUG_ON(sgi_source_id & ~7);
+       BUG_ON(sgi_source_id && irq >= VGIC_NR_SGIS);
+       BUG_ON(irq >= VGIC_NR_IRQS);
+
+       kvm_debug("Queue IRQ%d\n", irq);
+
+       lr = vgic_cpu->vgic_irq_lr_map[irq];
+
+       /* Do we have an active interrupt for the same CPUID? */
+       if (lr != LR_EMPTY &&
+           (LR_CPUID(vgic_cpu->vgic_lr[lr]) == sgi_source_id)) {
+               kvm_debug("LR%d piggyback for IRQ%d %x\n",
+                         lr, irq, vgic_cpu->vgic_lr[lr]);
+               BUG_ON(!test_bit(lr, vgic_cpu->lr_used));
+               vgic_cpu->vgic_lr[lr] |= GICH_LR_PENDING_BIT;
+               return true;
+       }
+
+       /* Try to use another LR for this interrupt */
+       lr = find_first_zero_bit((unsigned long *)vgic_cpu->lr_used,
+                              vgic_cpu->nr_lr);
+       if (lr >= vgic_cpu->nr_lr)
+               return false;
+
+       kvm_debug("LR%d allocated for IRQ%d %x\n", lr, irq, sgi_source_id);
+       vgic_cpu->vgic_lr[lr] = MK_LR_PEND(sgi_source_id, irq);
+       vgic_cpu->vgic_irq_lr_map[irq] = lr;
+       set_bit(lr, vgic_cpu->lr_used);
+
+       if (!vgic_irq_is_edge(vcpu, irq))
+               vgic_cpu->vgic_lr[lr] |= GICH_LR_EOI;
+
+       return true;
+}
+
+static bool vgic_queue_sgi(struct kvm_vcpu *vcpu, int irq)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+       unsigned long sources;
+       int vcpu_id = vcpu->vcpu_id;
+       int c;
+
+       sources = dist->irq_sgi_sources[vcpu_id][irq];
+
+       for_each_set_bit(c, &sources, VGIC_MAX_CPUS) {
+               if (vgic_queue_irq(vcpu, c, irq))
+                       clear_bit(c, &sources);
+       }
+
+       dist->irq_sgi_sources[vcpu_id][irq] = sources;
+
+       /*
+        * If the sources bitmap has been cleared it means that we
+        * could queue all the SGIs onto link registers (see the
+        * clear_bit above), and therefore we are done with them in
+        * our emulated gic and can get rid of them.
+        */
+       if (!sources) {
+               vgic_dist_irq_clear(vcpu, irq);
+               vgic_cpu_irq_clear(vcpu, irq);
+               return true;
+       }
+
+       return false;
+}
+
+static bool vgic_queue_hwirq(struct kvm_vcpu *vcpu, int irq)
+{
+       if (vgic_irq_is_active(vcpu, irq))
+               return true; /* level interrupt, already queued */
+
+       if (vgic_queue_irq(vcpu, 0, irq)) {
+               if (vgic_irq_is_edge(vcpu, irq)) {
+                       vgic_dist_irq_clear(vcpu, irq);
+                       vgic_cpu_irq_clear(vcpu, irq);
+               } else {
+                       vgic_irq_set_active(vcpu, irq);
+               }
+
+               return true;
+       }
+
+       return false;
+}
+
+/*
+ * Fill the list registers with pending interrupts before running the
+ * guest.
+ */
+static void __kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
+{
+       struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+       int i, vcpu_id;
+       int overflow = 0;
+
+       vcpu_id = vcpu->vcpu_id;
+
+       /*
+        * We may not have any pending interrupt, or the interrupts
+        * may have been serviced from another vcpu. In all cases,
+        * move along.
+        */
+       if (!kvm_vgic_vcpu_pending_irq(vcpu)) {
+               pr_debug("CPU%d has no pending interrupt\n", vcpu_id);
+               goto epilog;
+       }
+
+       /* SGIs */
+       for_each_set_bit(i, vgic_cpu->pending_percpu, VGIC_NR_SGIS) {
+               if (!vgic_queue_sgi(vcpu, i))
+                       overflow = 1;
+       }
+
+       /* PPIs */
+       for_each_set_bit_from(i, vgic_cpu->pending_percpu, VGIC_NR_PRIVATE_IRQS) {
+               if (!vgic_queue_hwirq(vcpu, i))
+                       overflow = 1;
+       }
+
+       /* SPIs */
+       for_each_set_bit(i, vgic_cpu->pending_shared, VGIC_NR_SHARED_IRQS) {
+               if (!vgic_queue_hwirq(vcpu, i + VGIC_NR_PRIVATE_IRQS))
+                       overflow = 1;
+       }
+
+epilog:
+       if (overflow) {
+               vgic_cpu->vgic_hcr |= GICH_HCR_UIE;
+       } else {
+               vgic_cpu->vgic_hcr &= ~GICH_HCR_UIE;
+               /*
+                * We're about to run this VCPU, and we've consumed
+                * everything the distributor had in store for
+                * us. Claim we don't have anything pending. We'll
+                * adjust that if needed while exiting.
+                */
+               clear_bit(vcpu_id, &dist->irq_pending_on_cpu);
+       }
+}
+
+static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
+{
+       struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+       bool level_pending = false;
+
+       kvm_debug("MISR = %08x\n", vgic_cpu->vgic_misr);
+
+       if (vgic_cpu->vgic_misr & GICH_MISR_EOI) {
+               /*
+                * Some level interrupts have been EOIed. Clear their
+                * active bit.
+                */
+               int lr, irq;
+
+               for_each_set_bit(lr, (unsigned long *)vgic_cpu->vgic_eisr,
+                                vgic_cpu->nr_lr) {
+                       irq = vgic_cpu->vgic_lr[lr] & GICH_LR_VIRTUALID;
+
+                       vgic_irq_clear_active(vcpu, irq);
+                       vgic_cpu->vgic_lr[lr] &= ~GICH_LR_EOI;
+
+                       /* Any additional pending interrupt? */
+                       if (vgic_dist_irq_is_pending(vcpu, irq)) {
+                               vgic_cpu_irq_set(vcpu, irq);
+                               level_pending = true;
+                       } else {
+                               vgic_cpu_irq_clear(vcpu, irq);
+                       }
+
+                       /*
+                        * Despite being EOIed, the LR may not have
+                        * been marked as empty.
+                        */
+                       set_bit(lr, (unsigned long *)vgic_cpu->vgic_elrsr);
+                       vgic_cpu->vgic_lr[lr] &= ~GICH_LR_ACTIVE_BIT;
+               }
+       }
+
+       if (vgic_cpu->vgic_misr & GICH_MISR_U)
+               vgic_cpu->vgic_hcr &= ~GICH_HCR_UIE;
+
+       return level_pending;
+}
+
+/*
+ * Sync back the VGIC state after a guest run. The distributor lock is
+ * needed so we don't get preempted in the middle of the state processing.
+ */
+static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
+{
+       struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+       int lr, pending;
+       bool level_pending;
+
+       level_pending = vgic_process_maintenance(vcpu);
+
+       /* Clear mappings for empty LRs */
+       for_each_set_bit(lr, (unsigned long *)vgic_cpu->vgic_elrsr,
+                        vgic_cpu->nr_lr) {
+               int irq;
+
+               if (!test_and_clear_bit(lr, vgic_cpu->lr_used))
+                       continue;
+
+               irq = vgic_cpu->vgic_lr[lr] & GICH_LR_VIRTUALID;
+
+               BUG_ON(irq >= VGIC_NR_IRQS);
+               vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY;
+       }
+
+       /* Check if we still have something up our sleeve... */
+       pending = find_first_zero_bit((unsigned long *)vgic_cpu->vgic_elrsr,
+                                     vgic_cpu->nr_lr);
+       if (level_pending || pending < vgic_cpu->nr_lr)
+               set_bit(vcpu->vcpu_id, &dist->irq_pending_on_cpu);
+}
+
+void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+       if (!irqchip_in_kernel(vcpu->kvm))
+               return;
+
+       spin_lock(&dist->lock);
+       __kvm_vgic_flush_hwstate(vcpu);
+       spin_unlock(&dist->lock);
+}
+
+void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+       if (!irqchip_in_kernel(vcpu->kvm))
+               return;
+
+       spin_lock(&dist->lock);
+       __kvm_vgic_sync_hwstate(vcpu);
+       spin_unlock(&dist->lock);
+}
+
+int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
+{
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+       if (!irqchip_in_kernel(vcpu->kvm))
+               return 0;
+
+       return test_bit(vcpu->vcpu_id, &dist->irq_pending_on_cpu);
+}
+
+static void vgic_kick_vcpus(struct kvm *kvm)
+{
+       struct kvm_vcpu *vcpu;
+       int c;
+
+       /*
+        * We've injected an interrupt, time to find out who deserves
+        * a good kick...
+        */
+       kvm_for_each_vcpu(c, vcpu, kvm) {
+               if (kvm_vgic_vcpu_pending_irq(vcpu))
+                       kvm_vcpu_kick(vcpu);
+       }
+}
+
+static int vgic_validate_injection(struct kvm_vcpu *vcpu, int irq, int level)
+{
+       int is_edge = vgic_irq_is_edge(vcpu, irq);
+       int state = vgic_dist_irq_is_pending(vcpu, irq);
+
+       /*
+        * Only inject an interrupt if:
+        * - edge triggered and we have a rising edge
+        * - level triggered and we change level
+        */
+       if (is_edge)
+               return level > state;
+       else
+               return level != state;
+}
+
+static bool vgic_update_irq_state(struct kvm *kvm, int cpuid,
+                                 unsigned int irq_num, bool level)
+{
+       struct vgic_dist *dist = &kvm->arch.vgic;
+       struct kvm_vcpu *vcpu;
+       int is_edge, is_level;
+       int enabled;
+       bool ret = true;
+
+       spin_lock(&dist->lock);
+
+       vcpu = kvm_get_vcpu(kvm, cpuid);
+       is_edge = vgic_irq_is_edge(vcpu, irq_num);
+       is_level = !is_edge;
+
+       if (!vgic_validate_injection(vcpu, irq_num, level)) {
+               ret = false;
+               goto out;
+       }
+
+       if (irq_num >= VGIC_NR_PRIVATE_IRQS) {
+               cpuid = dist->irq_spi_cpu[irq_num - VGIC_NR_PRIVATE_IRQS];
+               vcpu = kvm_get_vcpu(kvm, cpuid);
+       }
+
+       kvm_debug("Inject IRQ%d level %d CPU%d\n", irq_num, level, cpuid);
+
+       if (level)
+               vgic_dist_irq_set(vcpu, irq_num);
+       else
+               vgic_dist_irq_clear(vcpu, irq_num);
+
+       enabled = vgic_irq_is_enabled(vcpu, irq_num);
+
+       if (!enabled) {
+               ret = false;
+               goto out;
+       }
+
+       if (is_level && vgic_irq_is_active(vcpu, irq_num)) {
+               /*
+                * Level interrupt in progress, will be picked up
+                * when EOId.
+                */
+               ret = false;
+               goto out;
+       }
+
+       if (level) {
+               vgic_cpu_irq_set(vcpu, irq_num);
+               set_bit(cpuid, &dist->irq_pending_on_cpu);
+       }
+
+out:
+       spin_unlock(&dist->lock);
+
+       return ret;
+}
+
+/**
+ * kvm_vgic_inject_irq - Inject an IRQ from a device to the vgic
+ * @kvm:     The VM structure pointer
+ * @cpuid:   The CPU for PPIs
+ * @irq_num: The IRQ number that is assigned to the device
+ * @level:   Edge-triggered:  true:  to trigger the interrupt
+ *                           false: to ignore the call
+ *          Level-sensitive  true:  activates an interrupt
+ *                           false: deactivates an interrupt
+ *
+ * The GIC is not concerned with devices being active-LOW or active-HIGH for
+ * level-sensitive interrupts.  You can think of the level parameter as 1
+ * being HIGH and 0 being LOW and all devices being active-HIGH.
+ */
+int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num,
+                       bool level)
+{
+       if (vgic_update_irq_state(kvm, cpuid, irq_num, level))
+               vgic_kick_vcpus(kvm);
+
+       return 0;
+}
+
+static irqreturn_t vgic_maintenance_handler(int irq, void *data)
+{
+       /*
+        * We cannot rely on the vgic maintenance interrupt to be
+        * delivered synchronously. This means we can only use it to
+        * exit the VM, and we perform the handling of EOIed
+        * interrupts on the exit path (see vgic_process_maintenance).
+        */
+       return IRQ_HANDLED;
+}
+
+int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
+{
+       struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+       struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+       int i;
+
+       if (!irqchip_in_kernel(vcpu->kvm))
+               return 0;
+
+       if (vcpu->vcpu_id >= VGIC_MAX_CPUS)
+               return -EBUSY;
+
+       for (i = 0; i < VGIC_NR_IRQS; i++) {
+               if (i < VGIC_NR_PPIS)
+                       vgic_bitmap_set_irq_val(&dist->irq_enabled,
+                                               vcpu->vcpu_id, i, 1);
+               if (i < VGIC_NR_PRIVATE_IRQS)
+                       vgic_bitmap_set_irq_val(&dist->irq_cfg,
+                                               vcpu->vcpu_id, i, VGIC_CFG_EDGE);
+
+               vgic_cpu->vgic_irq_lr_map[i] = LR_EMPTY;
+       }
+
+       /*
+        * By forcing VMCR to zero, the GIC will restore the binary
+        * points to their reset values. Anything else resets to zero
+        * anyway.
+        */
+       vgic_cpu->vgic_vmcr = 0;
+
+       vgic_cpu->nr_lr = vgic_nr_lr;
+       vgic_cpu->vgic_hcr = GICH_HCR_EN; /* Get the show on the road... */
+
+       return 0;
+}
+
+static void vgic_init_maintenance_interrupt(void *info)
+{
+       enable_percpu_irq(vgic_maint_irq, 0);
+}
+
+static int vgic_cpu_notify(struct notifier_block *self,
+                          unsigned long action, void *cpu)
+{
+       switch (action) {
+       case CPU_STARTING:
+       case CPU_STARTING_FROZEN:
+               vgic_init_maintenance_interrupt(NULL);
+               break;
+       case CPU_DYING:
+       case CPU_DYING_FROZEN:
+               disable_percpu_irq(vgic_maint_irq);
+               break;
+       }
+
+       return NOTIFY_OK;
+}
+
+static struct notifier_block vgic_cpu_nb = {
+       .notifier_call = vgic_cpu_notify,
+};
+
+int kvm_vgic_hyp_init(void)
+{
+       int ret;
+       struct resource vctrl_res;
+       struct resource vcpu_res;
+
+       vgic_node = of_find_compatible_node(NULL, NULL, "arm,cortex-a15-gic");
+       if (!vgic_node) {
+               kvm_err("error: no compatible vgic node in DT\n");
+               return -ENODEV;
+       }
+
+       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 = request_percpu_irq(vgic_maint_irq, vgic_maintenance_handler,
+                                "vgic", kvm_get_running_vcpus());
+       if (ret) {
+               kvm_err("Cannot register interrupt %d\n", vgic_maint_irq);
+               goto out;
+       }
+
+       ret = register_cpu_notifier(&vgic_cpu_nb);
+       if (ret) {
+               kvm_err("Cannot register vgic CPU notifier\n");
+               goto out_free_irq;
+       }
+
+       ret = of_address_to_resource(vgic_node, 2, &vctrl_res);
+       if (ret) {
+               kvm_err("Cannot obtain VCTRL resource\n");
+               goto out_free_irq;
+       }
+
+       vgic_vctrl_base = of_iomap(vgic_node, 2);
+       if (!vgic_vctrl_base) {
+               kvm_err("Cannot ioremap VCTRL\n");
+               ret = -ENOMEM;
+               goto out_free_irq;
+       }
+
+       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;
+       }
+
+       kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
+                vctrl_res.start, vgic_maint_irq);
+       on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1);
+
+       if (of_address_to_resource(vgic_node, 3, &vcpu_res)) {
+               kvm_err("Cannot obtain VCPU resource\n");
+               ret = -ENXIO;
+               goto out_unmap;
+       }
+       vgic_vcpu_base = vcpu_res.start;
+
+       goto out;
+
+out_unmap:
+       iounmap(vgic_vctrl_base);
+out_free_irq:
+       free_percpu_irq(vgic_maint_irq, kvm_get_running_vcpus());
+out:
+       of_node_put(vgic_node);
+       return ret;
+}
+
+int kvm_vgic_init(struct kvm *kvm)
+{
+       int ret = 0, i;
+
+       mutex_lock(&kvm->lock);
+
+       if (vgic_initialized(kvm))
+               goto out;
+
+       if (IS_VGIC_ADDR_UNDEF(kvm->arch.vgic.vgic_dist_base) ||
+           IS_VGIC_ADDR_UNDEF(kvm->arch.vgic.vgic_cpu_base)) {
+               kvm_err("Need to set vgic cpu and dist addresses first\n");
+               ret = -ENXIO;
+               goto out;
+       }
+
+       ret = kvm_phys_addr_ioremap(kvm, kvm->arch.vgic.vgic_cpu_base,
+                                   vgic_vcpu_base, KVM_VGIC_V2_CPU_SIZE);
+       if (ret) {
+               kvm_err("Unable to remap VGIC CPU to VCPU\n");
+               goto out;
+       }
+
+       for (i = VGIC_NR_PRIVATE_IRQS; i < VGIC_NR_IRQS; i += 4)
+               vgic_set_target_reg(kvm, 0, i);
+
+       kvm_timer_init(kvm);
+       kvm->arch.vgic.ready = true;
+out:
+       mutex_unlock(&kvm->lock);
+       return ret;
+}
+
+int kvm_vgic_create(struct kvm *kvm)
+{
+       int ret = 0;
+
+       mutex_lock(&kvm->lock);
+
+       if (atomic_read(&kvm->online_vcpus) || kvm->arch.vgic.vctrl_base) {
+               ret = -EEXIST;
+               goto out;
+       }
+
+       spin_lock_init(&kvm->arch.vgic.lock);
+       kvm->arch.vgic.vctrl_base = vgic_vctrl_base;
+       kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;
+       kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
+
+out:
+       mutex_unlock(&kvm->lock);
+       return ret;
+}
+
+static bool vgic_ioaddr_overlap(struct kvm *kvm)
+{
+       phys_addr_t dist = kvm->arch.vgic.vgic_dist_base;
+       phys_addr_t cpu = kvm->arch.vgic.vgic_cpu_base;
+
+       if (IS_VGIC_ADDR_UNDEF(dist) || IS_VGIC_ADDR_UNDEF(cpu))
+               return 0;
+       if ((dist <= cpu && dist + KVM_VGIC_V2_DIST_SIZE > cpu) ||
+           (cpu <= dist && cpu + KVM_VGIC_V2_CPU_SIZE > dist))
+               return -EBUSY;
+       return 0;
+}
+
+static int vgic_ioaddr_assign(struct kvm *kvm, phys_addr_t *ioaddr,
+                             phys_addr_t addr, phys_addr_t size)
+{
+       int ret;
+
+       if (!IS_VGIC_ADDR_UNDEF(*ioaddr))
+               return -EEXIST;
+       if (addr + size < addr)
+               return -EINVAL;
+
+       ret = vgic_ioaddr_overlap(kvm);
+       if (ret)
+               return ret;
+       *ioaddr = addr;
+       return ret;
+}
+
+int kvm_vgic_set_addr(struct kvm *kvm, unsigned long type, u64 addr)
+{
+       int r = 0;
+       struct vgic_dist *vgic = &kvm->arch.vgic;
+
+       if (addr & ~KVM_PHYS_MASK)
+               return -E2BIG;
+
+       if (addr & (SZ_4K - 1))
+               return -EINVAL;
+
+       mutex_lock(&kvm->lock);
+       switch (type) {
+       case KVM_VGIC_V2_ADDR_TYPE_DIST:
+               r = vgic_ioaddr_assign(kvm, &vgic->vgic_dist_base,
+                                      addr, KVM_VGIC_V2_DIST_SIZE);
+               break;
+       case KVM_VGIC_V2_ADDR_TYPE_CPU:
+               r = vgic_ioaddr_assign(kvm, &vgic->vgic_cpu_base,
+                                      addr, KVM_VGIC_V2_CPU_SIZE);
+               break;
+       default:
+               r = -ENODEV;
+       }
+
+       mutex_unlock(&kvm->lock);
+       return r;
+}