virt/kvm/arm/vgic/vgic-v3.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License version 2 as
   4  * published by the Free Software Foundation.
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * You should have received a copy of the GNU General Public License
  12  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  13  */
  14
  15 #include <linux/irqchip/arm-gic-v3.h>
  16 #include <linux/kvm.h>
  17 #include <linux/kvm_host.h>
  18 #include <kvm/arm_vgic.h>
  19 #include <asm/kvm_mmu.h>
  20 #include <asm/kvm_asm.h>
  21
  22 #include "vgic.h"
  23
  24 void vgic_v3_process_maintenance(struct kvm_vcpu *vcpu)
  25 {
  26         struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
  27         u32 model = vcpu->kvm->arch.vgic.vgic_model;
  28
  29         if (cpuif->vgic_misr & ICH_MISR_EOI) {
  30                 unsigned long eisr_bmap = cpuif->vgic_eisr;
  31                 int lr;
  32
  33                 for_each_set_bit(lr, &eisr_bmap, kvm_vgic_global_state.nr_lr) {
  34                         u32 intid;
  35                         u64 val = cpuif->vgic_lr[lr];
  36
  37                         if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
  38                                 intid = val & ICH_LR_VIRTUAL_ID_MASK;
  39                         else
  40                                 intid = val & GICH_LR_VIRTUALID;
  41
  42                         WARN_ON(cpuif->vgic_lr[lr] & ICH_LR_STATE);
  43
  44                         kvm_notify_acked_irq(vcpu->kvm, 0,
  45                                              intid - VGIC_NR_PRIVATE_IRQS);
  46                 }
  47
  48                 /*
  49                  * In the next iterations of the vcpu loop, if we sync
  50                  * the vgic state after flushing it, but before
  51                  * entering the guest (this happens for pending
  52                  * signals and vmid rollovers), then make sure we
  53                  * don't pick up any old maintenance interrupts here.
  54                  */
  55                 cpuif->vgic_eisr = 0;
  56         }
  57
  58         cpuif->vgic_hcr &= ~ICH_HCR_UIE;
  59 }
  60
  61 void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
  62 {
  63         struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
  64
  65         cpuif->vgic_hcr |= ICH_HCR_UIE;
  66 }
  67
  68 void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
  69 {
  70         struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
  71         u32 model = vcpu->kvm->arch.vgic.vgic_model;
  72         int lr;
  73
  74         for (lr = 0; lr < vcpu->arch.vgic_cpu.used_lrs; lr++) {
  75                 u64 val = cpuif->vgic_lr[lr];
  76                 u32 intid;
  77                 struct vgic_irq *irq;
  78
  79                 if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
  80                         intid = val & ICH_LR_VIRTUAL_ID_MASK;
  81                 else
  82                         intid = val & GICH_LR_VIRTUALID;
  83                 irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
  84                 if (!irq)       /* An LPI could have been unmapped. */
  85                         continue;
  86
  87                 spin_lock(&irq->irq_lock);
  88
  89                 /* Always preserve the active bit */
  90                 irq->active = !!(val & ICH_LR_ACTIVE_BIT);
  91
  92                 /* Edge is the only case where we preserve the pending bit */
  93                 if (irq->config == VGIC_CONFIG_EDGE &&
  94                     (val & ICH_LR_PENDING_BIT)) {
  95                         irq->pending = true;
  96
  97                         if (vgic_irq_is_sgi(intid) &&
  98                             model == KVM_DEV_TYPE_ARM_VGIC_V2) {
  99                                 u32 cpuid = val & GICH_LR_PHYSID_CPUID;
 100
 101                                 cpuid >>= GICH_LR_PHYSID_CPUID_SHIFT;
 102                                 irq->source |= (1 << cpuid);
 103                         }
 104                 }
 105
 106                 /*
 107                  * Clear soft pending state when level irqs have been acked.
 108                  * Always regenerate the pending state.
 109                  */
 110                 if (irq->config == VGIC_CONFIG_LEVEL) {
 111                         if (!(val & ICH_LR_PENDING_BIT))
 112                                 irq->soft_pending = false;
 113
 114                         irq->pending = irq->line_level || irq->soft_pending;
 115                 }
 116
 117                 spin_unlock(&irq->irq_lock);
 118                 vgic_put_irq(vcpu->kvm, irq);
 119         }
 120 }
 121
 122 /* Requires the irq to be locked already */
 123 void vgic_v3_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
 124 {
 125         u32 model = vcpu->kvm->arch.vgic.vgic_model;
 126         u64 val = irq->intid;
 127
 128         if (irq->pending) {
 129                 val |= ICH_LR_PENDING_BIT;
 130
 131                 if (irq->config == VGIC_CONFIG_EDGE)
 132                         irq->pending = false;
 133
 134                 if (vgic_irq_is_sgi(irq->intid) &&
 135                     model == KVM_DEV_TYPE_ARM_VGIC_V2) {
 136                         u32 src = ffs(irq->source);
 137
 138                         BUG_ON(!src);
 139                         val |= (src - 1) << GICH_LR_PHYSID_CPUID_SHIFT;
 140                         irq->source &= ~(1 << (src - 1));
 141                         if (irq->source)
 142                                 irq->pending = true;
 143                 }
 144         }
 145
 146         if (irq->active)
 147                 val |= ICH_LR_ACTIVE_BIT;
 148
 149         if (irq->hw) {
 150                 val |= ICH_LR_HW;
 151                 val |= ((u64)irq->hwintid) << ICH_LR_PHYS_ID_SHIFT;
 152         } else {
 153                 if (irq->config == VGIC_CONFIG_LEVEL)
 154                         val |= ICH_LR_EOI;
 155         }
 156
 157         /*
 158          * We currently only support Group1 interrupts, which is a
 159          * known defect. This needs to be addressed at some point.
 160          */
 161         if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
 162                 val |= ICH_LR_GROUP;
 163
 164         val |= (u64)irq->priority << ICH_LR_PRIORITY_SHIFT;
 165
 166         vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = val;
 167 }
 168
 169 void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr)
 170 {
 171         vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = 0;
 172 }
 173
 174 void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
 175 {
 176         u32 vmcr;
 177
 178         vmcr  = (vmcrp->ctlr << ICH_VMCR_CTLR_SHIFT) & ICH_VMCR_CTLR_MASK;
 179         vmcr |= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
 180         vmcr |= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
 181         vmcr |= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;
 182
 183         vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = vmcr;
 184 }
 185
 186 void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
 187 {
 188         u32 vmcr = vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr;
 189
 190         vmcrp->ctlr = (vmcr & ICH_VMCR_CTLR_MASK) >> ICH_VMCR_CTLR_SHIFT;
 191         vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
 192         vmcrp->bpr  = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
 193         vmcrp->pmr  = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
 194 }
 195
 196 #define INITIAL_PENDBASER_VALUE                                           \
 197         (GIC_BASER_CACHEABILITY(GICR_PENDBASER, INNER, RaWb)            | \
 198         GIC_BASER_CACHEABILITY(GICR_PENDBASER, OUTER, SameAsInner)      | \
 199         GIC_BASER_SHAREABILITY(GICR_PENDBASER, InnerShareable))
 200
 201 void vgic_v3_enable(struct kvm_vcpu *vcpu)
 202 {
 203         struct vgic_v3_cpu_if *vgic_v3 = &vcpu->arch.vgic_cpu.vgic_v3;
 204
 205         /*
 206          * By forcing VMCR to zero, the GIC will restore the binary
 207          * points to their reset values. Anything else resets to zero
 208          * anyway.
 209          */
 210         vgic_v3->vgic_vmcr = 0;
 211         vgic_v3->vgic_elrsr = ~0;
 212
 213         /*
 214          * If we are emulating a GICv3, we do it in an non-GICv2-compatible
 215          * way, so we force SRE to 1 to demonstrate this to the guest.
 216          * This goes with the spec allowing the value to be RAO/WI.
 217          */
 218         if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
 219                 vgic_v3->vgic_sre = ICC_SRE_EL1_SRE;
 220                 vcpu->arch.vgic_cpu.pendbaser = INITIAL_PENDBASER_VALUE;
 221         } else {
 222                 vgic_v3->vgic_sre = 0;
 223         }
 224
 225         /* Get the show on the road... */
 226         vgic_v3->vgic_hcr = ICH_HCR_EN;
 227 }
 228
 229 /* check for overlapping regions and for regions crossing the end of memory */
 230 static bool vgic_v3_check_base(struct kvm *kvm)
 231 {
 232         struct vgic_dist *d = &kvm->arch.vgic;
 233         gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;
 234
 235         redist_size *= atomic_read(&kvm->online_vcpus);
 236
 237         if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
 238                 return false;
 239         if (d->vgic_redist_base + redist_size < d->vgic_redist_base)
 240                 return false;
 241
 242         if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= d->vgic_redist_base)
 243                 return true;
 244         if (d->vgic_redist_base + redist_size <= d->vgic_dist_base)
 245                 return true;
 246
 247         return false;
 248 }
 249
 250 int vgic_v3_map_resources(struct kvm *kvm)
 251 {
 252         int ret = 0;
 253         struct vgic_dist *dist = &kvm->arch.vgic;
 254
 255         if (vgic_ready(kvm))
 256                 goto out;
 257
 258         if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) ||
 259             IS_VGIC_ADDR_UNDEF(dist->vgic_redist_base)) {
 260                 kvm_err("Need to set vgic distributor addresses first\n");
 261                 ret = -ENXIO;
 262                 goto out;
 263         }
 264
 265         if (!vgic_v3_check_base(kvm)) {
 266                 kvm_err("VGIC redist and dist frames overlap\n");
 267                 ret = -EINVAL;
 268                 goto out;
 269         }
 270
 271         /*
 272          * For a VGICv3 we require the userland to explicitly initialize
 273          * the VGIC before we need to use it.
 274          */
 275         if (!vgic_initialized(kvm)) {
 276                 ret = -EBUSY;
 277                 goto out;
 278         }
 279
 280         ret = vgic_register_dist_iodev(kvm, dist->vgic_dist_base, VGIC_V3);
 281         if (ret) {
 282                 kvm_err("Unable to register VGICv3 dist MMIO regions\n");
 283                 goto out;
 284         }
 285
 286         ret = vgic_register_redist_iodevs(kvm, dist->vgic_redist_base);
 287         if (ret) {
 288                 kvm_err("Unable to register VGICv3 redist MMIO regions\n");
 289                 goto out;
 290         }
 291
 292         dist->ready = true;
 293
 294 out:
 295         if (ret)
 296                 kvm_vgic_destroy(kvm);
 297         return ret;
 298 }
 299
 300 /**
 301  * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
 302  * @node:       pointer to the DT node
 303  *
 304  * Returns 0 if a GICv3 has been found, returns an error code otherwise
 305  */
 306 int vgic_v3_probe(const struct gic_kvm_info *info)
 307 {
 308         u32 ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);
 309         int ret;
 310
 311         /*
 312          * The ListRegs field is 5 bits, but there is a architectural
 313          * maximum of 16 list registers. Just ignore bit 4...
 314          */
 315         kvm_vgic_global_state.nr_lr = (ich_vtr_el2 & 0xf) + 1;
 316         kvm_vgic_global_state.can_emulate_gicv2 = false;
 317
 318         if (!info->vcpu.start) {
 319                 kvm_info("GICv3: no GICV resource entry\n");
 320                 kvm_vgic_global_state.vcpu_base = 0;
 321         } else if (!PAGE_ALIGNED(info->vcpu.start)) {
 322                 pr_warn("GICV physical address 0x%llx not page aligned\n",
 323                         (unsigned long long)info->vcpu.start);
 324                 kvm_vgic_global_state.vcpu_base = 0;
 325         } else if (!PAGE_ALIGNED(resource_size(&info->vcpu))) {
 326                 pr_warn("GICV size 0x%llx not a multiple of page size 0x%lx\n",
 327                         (unsigned long long)resource_size(&info->vcpu),
 328                         PAGE_SIZE);
 329                 kvm_vgic_global_state.vcpu_base = 0;
 330         } else {
 331                 kvm_vgic_global_state.vcpu_base = info->vcpu.start;
 332                 kvm_vgic_global_state.can_emulate_gicv2 = true;
 333                 ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
 334                 if (ret) {
 335                         kvm_err("Cannot register GICv2 KVM device.\n");
 336                         return ret;
 337                 }
 338                 kvm_info("vgic-v2@%llx\n", info->vcpu.start);
 339         }
 340         ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V3);
 341         if (ret) {
 342                 kvm_err("Cannot register GICv3 KVM device.\n");
 343                 kvm_unregister_device_ops(KVM_DEV_TYPE_ARM_VGIC_V2);
 344                 return ret;
 345         }
 346
 347         if (kvm_vgic_global_state.vcpu_base == 0)
 348                 kvm_info("disabling GICv2 emulation\n");
 349
 350         kvm_vgic_global_state.vctrl_base = NULL;
 351         kvm_vgic_global_state.type = VGIC_V3;
 352         kvm_vgic_global_state.max_gic_vcpus = VGIC_V3_MAX_CPUS;
 353
 354         return 0;
 355 }