virt/kvm/arm/vgic/vgic-mmio-v2.c

   1 /*
   2  * VGICv2 MMIO handling functions
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <linux/irqchip/arm-gic.h>
  15 #include <linux/kvm.h>
  16 #include <linux/kvm_host.h>
  17 #include <kvm/iodev.h>
  18 #include <kvm/arm_vgic.h>
  19
  20 #include "vgic.h"
  21 #include "vgic-mmio.h"
  22
  23 static unsigned long vgic_mmio_read_v2_misc(struct kvm_vcpu *vcpu,
  24                                             gpa_t addr, unsigned int len)
  25 {
  26         u32 value;
  27
  28         switch (addr & 0x0c) {
  29         case GIC_DIST_CTRL:
  30                 value = vcpu->kvm->arch.vgic.enabled ? GICD_ENABLE : 0;
  31                 break;
  32         case GIC_DIST_CTR:
  33                 value = vcpu->kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS;
  34                 value = (value >> 5) - 1;
  35                 value |= (atomic_read(&vcpu->kvm->online_vcpus) - 1) << 5;
  36                 break;
  37         case GIC_DIST_IIDR:
  38                 value = (PRODUCT_ID_KVM << 24) | (IMPLEMENTER_ARM << 0);
  39                 break;
  40         default:
  41                 return 0;
  42         }
  43
  44         return value;
  45 }
  46
  47 static void vgic_mmio_write_v2_misc(struct kvm_vcpu *vcpu,
  48                                     gpa_t addr, unsigned int len,
  49                                     unsigned long val)
  50 {
  51         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
  52         bool was_enabled = dist->enabled;
  53
  54         switch (addr & 0x0c) {
  55         case GIC_DIST_CTRL:
  56                 dist->enabled = val & GICD_ENABLE;
  57                 if (!was_enabled && dist->enabled)
  58                         vgic_kick_vcpus(vcpu->kvm);
  59                 break;
  60         case GIC_DIST_CTR:
  61         case GIC_DIST_IIDR:
  62                 /* Nothing to do */
  63                 return;
  64         }
  65 }
  66
  67 static void vgic_mmio_write_sgir(struct kvm_vcpu *source_vcpu,
  68                                  gpa_t addr, unsigned int len,
  69                                  unsigned long val)
  70 {
  71         int nr_vcpus = atomic_read(&source_vcpu->kvm->online_vcpus);
  72         int intid = val & 0xf;
  73         int targets = (val >> 16) & 0xff;
  74         int mode = (val >> 24) & 0x03;
  75         int c;
  76         struct kvm_vcpu *vcpu;
  77
  78         switch (mode) {
  79         case 0x0:               /* as specified by targets */
  80                 break;
  81         case 0x1:
  82                 targets = (1U << nr_vcpus) - 1;                 /* all, ... */
  83                 targets &= ~(1U << source_vcpu->vcpu_id);       /* but self */
  84                 break;
  85         case 0x2:               /* this very vCPU only */
  86                 targets = (1U << source_vcpu->vcpu_id);
  87                 break;
  88         case 0x3:               /* reserved */
  89                 return;
  90         }
  91
  92         kvm_for_each_vcpu(c, vcpu, source_vcpu->kvm) {
  93                 struct vgic_irq *irq;
  94
  95                 if (!(targets & (1U << c)))
  96                         continue;
  97
  98                 irq = vgic_get_irq(source_vcpu->kvm, vcpu, intid);
  99
 100                 spin_lock(&irq->irq_lock);
 101                 irq->pending = true;
 102                 irq->source |= 1U << source_vcpu->vcpu_id;
 103
 104                 vgic_queue_irq_unlock(source_vcpu->kvm, irq);
 105                 vgic_put_irq(source_vcpu->kvm, irq);
 106         }
 107 }
 108
 109 static unsigned long vgic_mmio_read_target(struct kvm_vcpu *vcpu,
 110                                            gpa_t addr, unsigned int len)
 111 {
 112         u32 intid = VGIC_ADDR_TO_INTID(addr, 8);
 113         int i;
 114         u64 val = 0;
 115
 116         for (i = 0; i < len; i++) {
 117                 struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
 118
 119                 val |= (u64)irq->targets << (i * 8);
 120
 121                 vgic_put_irq(vcpu->kvm, irq);
 122         }
 123
 124         return val;
 125 }
 126
 127 static void vgic_mmio_write_target(struct kvm_vcpu *vcpu,
 128                                    gpa_t addr, unsigned int len,
 129                                    unsigned long val)
 130 {
 131         u32 intid = VGIC_ADDR_TO_INTID(addr, 8);
 132         int i;
 133
 134         /* GICD_ITARGETSR[0-7] are read-only */
 135         if (intid < VGIC_NR_PRIVATE_IRQS)
 136                 return;
 137
 138         for (i = 0; i < len; i++) {
 139                 struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, NULL, intid + i);
 140                 int target;
 141
 142                 spin_lock(&irq->irq_lock);
 143
 144                 irq->targets = (val >> (i * 8)) & 0xff;
 145                 target = irq->targets ? __ffs(irq->targets) : 0;
 146                 irq->target_vcpu = kvm_get_vcpu(vcpu->kvm, target);
 147
 148                 spin_unlock(&irq->irq_lock);
 149                 vgic_put_irq(vcpu->kvm, irq);
 150         }
 151 }
 152
 153 static unsigned long vgic_mmio_read_sgipend(struct kvm_vcpu *vcpu,
 154                                             gpa_t addr, unsigned int len)
 155 {
 156         u32 intid = addr & 0x0f;
 157         int i;
 158         u64 val = 0;
 159
 160         for (i = 0; i < len; i++) {
 161                 struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
 162
 163                 val |= (u64)irq->source << (i * 8);
 164
 165                 vgic_put_irq(vcpu->kvm, irq);
 166         }
 167         return val;
 168 }
 169
 170 static void vgic_mmio_write_sgipendc(struct kvm_vcpu *vcpu,
 171                                      gpa_t addr, unsigned int len,
 172                                      unsigned long val)
 173 {
 174         u32 intid = addr & 0x0f;
 175         int i;
 176
 177         for (i = 0; i < len; i++) {
 178                 struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
 179
 180                 spin_lock(&irq->irq_lock);
 181
 182                 irq->source &= ~((val >> (i * 8)) & 0xff);
 183                 if (!irq->source)
 184                         irq->pending = false;
 185
 186                 spin_unlock(&irq->irq_lock);
 187                 vgic_put_irq(vcpu->kvm, irq);
 188         }
 189 }
 190
 191 static void vgic_mmio_write_sgipends(struct kvm_vcpu *vcpu,
 192                                      gpa_t addr, unsigned int len,
 193                                      unsigned long val)
 194 {
 195         u32 intid = addr & 0x0f;
 196         int i;
 197
 198         for (i = 0; i < len; i++) {
 199                 struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
 200
 201                 spin_lock(&irq->irq_lock);
 202
 203                 irq->source |= (val >> (i * 8)) & 0xff;
 204
 205                 if (irq->source) {
 206                         irq->pending = true;
 207                         vgic_queue_irq_unlock(vcpu->kvm, irq);
 208                 } else {
 209                         spin_unlock(&irq->irq_lock);
 210                 }
 211                 vgic_put_irq(vcpu->kvm, irq);
 212         }
 213 }
 214
 215 static void vgic_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
 216 {
 217         if (kvm_vgic_global_state.type == VGIC_V2)
 218                 vgic_v2_set_vmcr(vcpu, vmcr);
 219         else
 220                 vgic_v3_set_vmcr(vcpu, vmcr);
 221 }
 222
 223 static void vgic_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
 224 {
 225         if (kvm_vgic_global_state.type == VGIC_V2)
 226                 vgic_v2_get_vmcr(vcpu, vmcr);
 227         else
 228                 vgic_v3_get_vmcr(vcpu, vmcr);
 229 }
 230
 231 #define GICC_ARCH_VERSION_V2    0x2
 232
 233 /* These are for userland accesses only, there is no guest-facing emulation. */
 234 static unsigned long vgic_mmio_read_vcpuif(struct kvm_vcpu *vcpu,
 235                                            gpa_t addr, unsigned int len)
 236 {
 237         struct vgic_vmcr vmcr;
 238         u32 val;
 239
 240         vgic_get_vmcr(vcpu, &vmcr);
 241
 242         switch (addr & 0xff) {
 243         case GIC_CPU_CTRL:
 244                 val = vmcr.ctlr;
 245                 break;
 246         case GIC_CPU_PRIMASK:
 247                 val = vmcr.pmr;
 248                 break;
 249         case GIC_CPU_BINPOINT:
 250                 val = vmcr.bpr;
 251                 break;
 252         case GIC_CPU_ALIAS_BINPOINT:
 253                 val = vmcr.abpr;
 254                 break;
 255         case GIC_CPU_IDENT:
 256                 val = ((PRODUCT_ID_KVM << 20) |
 257                        (GICC_ARCH_VERSION_V2 << 16) |
 258                        IMPLEMENTER_ARM);
 259                 break;
 260         default:
 261                 return 0;
 262         }
 263
 264         return val;
 265 }
 266
 267 static void vgic_mmio_write_vcpuif(struct kvm_vcpu *vcpu,
 268                                    gpa_t addr, unsigned int len,
 269                                    unsigned long val)
 270 {
 271         struct vgic_vmcr vmcr;
 272
 273         vgic_get_vmcr(vcpu, &vmcr);
 274
 275         switch (addr & 0xff) {
 276         case GIC_CPU_CTRL:
 277                 vmcr.ctlr = val;
 278                 break;
 279         case GIC_CPU_PRIMASK:
 280                 vmcr.pmr = val;
 281                 break;
 282         case GIC_CPU_BINPOINT:
 283                 vmcr.bpr = val;
 284                 break;
 285         case GIC_CPU_ALIAS_BINPOINT:
 286                 vmcr.abpr = val;
 287                 break;
 288         }
 289
 290         vgic_set_vmcr(vcpu, &vmcr);
 291 }
 292
 293 static const struct vgic_register_region vgic_v2_dist_registers[] = {
 294         REGISTER_DESC_WITH_LENGTH(GIC_DIST_CTRL,
 295                 vgic_mmio_read_v2_misc, vgic_mmio_write_v2_misc, 12,
 296                 VGIC_ACCESS_32bit),
 297         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_IGROUP,
 298                 vgic_mmio_read_rao, vgic_mmio_write_wi, 1,
 299                 VGIC_ACCESS_32bit),
 300         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ENABLE_SET,
 301                 vgic_mmio_read_enable, vgic_mmio_write_senable, 1,
 302                 VGIC_ACCESS_32bit),
 303         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ENABLE_CLEAR,
 304                 vgic_mmio_read_enable, vgic_mmio_write_cenable, 1,
 305                 VGIC_ACCESS_32bit),
 306         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PENDING_SET,
 307                 vgic_mmio_read_pending, vgic_mmio_write_spending, 1,
 308                 VGIC_ACCESS_32bit),
 309         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PENDING_CLEAR,
 310                 vgic_mmio_read_pending, vgic_mmio_write_cpending, 1,
 311                 VGIC_ACCESS_32bit),
 312         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_SET,
 313                 vgic_mmio_read_active, vgic_mmio_write_sactive, 1,
 314                 VGIC_ACCESS_32bit),
 315         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_CLEAR,
 316                 vgic_mmio_read_active, vgic_mmio_write_cactive, 1,
 317                 VGIC_ACCESS_32bit),
 318         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PRI,
 319                 vgic_mmio_read_priority, vgic_mmio_write_priority, 8,
 320                 VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
 321         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_TARGET,
 322                 vgic_mmio_read_target, vgic_mmio_write_target, 8,
 323                 VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
 324         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_CONFIG,
 325                 vgic_mmio_read_config, vgic_mmio_write_config, 2,
 326                 VGIC_ACCESS_32bit),
 327         REGISTER_DESC_WITH_LENGTH(GIC_DIST_SOFTINT,
 328                 vgic_mmio_read_raz, vgic_mmio_write_sgir, 4,
 329                 VGIC_ACCESS_32bit),
 330         REGISTER_DESC_WITH_LENGTH(GIC_DIST_SGI_PENDING_CLEAR,
 331                 vgic_mmio_read_sgipend, vgic_mmio_write_sgipendc, 16,
 332                 VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
 333         REGISTER_DESC_WITH_LENGTH(GIC_DIST_SGI_PENDING_SET,
 334                 vgic_mmio_read_sgipend, vgic_mmio_write_sgipends, 16,
 335                 VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
 336 };
 337
 338 static const struct vgic_register_region vgic_v2_cpu_registers[] = {
 339         REGISTER_DESC_WITH_LENGTH(GIC_CPU_CTRL,
 340                 vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4,
 341                 VGIC_ACCESS_32bit),
 342         REGISTER_DESC_WITH_LENGTH(GIC_CPU_PRIMASK,
 343                 vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4,
 344                 VGIC_ACCESS_32bit),
 345         REGISTER_DESC_WITH_LENGTH(GIC_CPU_BINPOINT,
 346                 vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4,
 347                 VGIC_ACCESS_32bit),
 348         REGISTER_DESC_WITH_LENGTH(GIC_CPU_ALIAS_BINPOINT,
 349                 vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4,
 350                 VGIC_ACCESS_32bit),
 351         REGISTER_DESC_WITH_LENGTH(GIC_CPU_ACTIVEPRIO,
 352                 vgic_mmio_read_raz, vgic_mmio_write_wi, 16,
 353                 VGIC_ACCESS_32bit),
 354         REGISTER_DESC_WITH_LENGTH(GIC_CPU_IDENT,
 355                 vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4,
 356                 VGIC_ACCESS_32bit),
 357 };
 358
 359 unsigned int vgic_v2_init_dist_iodev(struct vgic_io_device *dev)
 360 {
 361         dev->regions = vgic_v2_dist_registers;
 362         dev->nr_regions = ARRAY_SIZE(vgic_v2_dist_registers);
 363
 364         kvm_iodevice_init(&dev->dev, &kvm_io_gic_ops);
 365
 366         return SZ_4K;
 367 }
 368
 369 int vgic_v2_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr)
 370 {
 371         int nr_irqs = dev->kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS;
 372         const struct vgic_register_region *regions;
 373         gpa_t addr;
 374         int nr_regions, i, len;
 375
 376         addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
 377
 378         switch (attr->group) {
 379         case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
 380                 regions = vgic_v2_dist_registers;
 381                 nr_regions = ARRAY_SIZE(vgic_v2_dist_registers);
 382                 break;
 383         case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
 384                 regions = vgic_v2_cpu_registers;
 385                 nr_regions = ARRAY_SIZE(vgic_v2_cpu_registers);
 386                 break;
 387         default:
 388                 return -ENXIO;
 389         }
 390
 391         /* We only support aligned 32-bit accesses. */
 392         if (addr & 3)
 393                 return -ENXIO;
 394
 395         for (i = 0; i < nr_regions; i++) {
 396                 if (regions[i].bits_per_irq)
 397                         len = (regions[i].bits_per_irq * nr_irqs) / 8;
 398                 else
 399                         len = regions[i].len;
 400
 401                 if (regions[i].reg_offset <= addr &&
 402                     regions[i].reg_offset + len > addr)
 403                         return 0;
 404         }
 405
 406         return -ENXIO;
 407 }
 408
 409 /*
 410  * When userland tries to access the VGIC register handlers, we need to
 411  * create a usable struct vgic_io_device to be passed to the handlers and we
 412  * have to set up a buffer similar to what would have happened if a guest MMIO
 413  * access occurred, including doing endian conversions on BE systems.
 414  */
 415 static int vgic_uaccess(struct kvm_vcpu *vcpu, struct vgic_io_device *dev,
 416                         bool is_write, int offset, u32 *val)
 417 {
 418         unsigned int len = 4;
 419         u8 buf[4];
 420         int ret;
 421
 422         if (is_write) {
 423                 vgic_data_host_to_mmio_bus(buf, len, *val);
 424                 ret = kvm_io_gic_ops.write(vcpu, &dev->dev, offset, len, buf);
 425         } else {
 426                 ret = kvm_io_gic_ops.read(vcpu, &dev->dev, offset, len, buf);
 427                 if (!ret)
 428                         *val = vgic_data_mmio_bus_to_host(buf, len);
 429         }
 430
 431         return ret;
 432 }
 433
 434 int vgic_v2_cpuif_uaccess(struct kvm_vcpu *vcpu, bool is_write,
 435                           int offset, u32 *val)
 436 {
 437         struct vgic_io_device dev = {
 438                 .regions = vgic_v2_cpu_registers,
 439                 .nr_regions = ARRAY_SIZE(vgic_v2_cpu_registers),
 440                 .iodev_type = IODEV_CPUIF,
 441         };
 442
 443         return vgic_uaccess(vcpu, &dev, is_write, offset, val);
 444 }
 445
 446 int vgic_v2_dist_uaccess(struct kvm_vcpu *vcpu, bool is_write,
 447                          int offset, u32 *val)
 448 {
 449         struct vgic_io_device dev = {
 450                 .regions = vgic_v2_dist_registers,
 451                 .nr_regions = ARRAY_SIZE(vgic_v2_dist_registers),
 452                 .iodev_type = IODEV_DIST,
 453         };
 454
 455         return vgic_uaccess(vcpu, &dev, is_write, offset, val);
 456 }