hw/intc/xics_kvm.c

   1 /*
   2  * QEMU PowerPC pSeries Logical Partition (aka sPAPR) hardware System Emulator
   3  *
   4  * PAPR Virtualized Interrupt System, aka ICS/ICP aka xics, in-kernel emulation
   5  *
   6  * Copyright (c) 2013 David Gibson, IBM Corporation.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  24  * THE SOFTWARE.
  25  *
  26  */
  27
  28 #include "qemu/osdep.h"
  29 #include "qapi/error.h"
  30 #include "qemu-common.h"
  31 #include "cpu.h"
  32 #include "hw/hw.h"
  33 #include "trace.h"
  34 #include "sysemu/kvm.h"
  35 #include "hw/ppc/spapr.h"
  36 #include "hw/ppc/xics.h"
  37 #include "hw/ppc/xics_spapr.h"
  38 #include "kvm_ppc.h"
  39 #include "qemu/config-file.h"
  40 #include "qemu/error-report.h"
  41
  42 #include <sys/ioctl.h>
  43
  44 static int kernel_xics_fd = -1;
  45
  46 typedef struct KVMEnabledICP {
  47     unsigned long vcpu_id;
  48     QLIST_ENTRY(KVMEnabledICP) node;
  49 } KVMEnabledICP;
  50
  51 static QLIST_HEAD(, KVMEnabledICP)
  52     kvm_enabled_icps = QLIST_HEAD_INITIALIZER(&kvm_enabled_icps);
  53
  54 /*
  55  * ICP-KVM
  56  */
  57 void icp_get_kvm_state(ICPState *icp)
  58 {
  59     uint64_t state;
  60     int ret;
  61
  62     /* ICP for this CPU thread is not in use, exiting */
  63     if (!icp->cs) {
  64         return;
  65     }
  66
  67     ret = kvm_get_one_reg(icp->cs, KVM_REG_PPC_ICP_STATE, &state);
  68     if (ret != 0) {
  69         error_report("Unable to retrieve KVM interrupt controller state"
  70                 " for CPU %ld: %s", kvm_arch_vcpu_id(icp->cs), strerror(errno));
  71         exit(1);
  72     }
  73
  74     icp->xirr = state >> KVM_REG_PPC_ICP_XISR_SHIFT;
  75     icp->mfrr = (state >> KVM_REG_PPC_ICP_MFRR_SHIFT)
  76         & KVM_REG_PPC_ICP_MFRR_MASK;
  77     icp->pending_priority = (state >> KVM_REG_PPC_ICP_PPRI_SHIFT)
  78         & KVM_REG_PPC_ICP_PPRI_MASK;
  79 }
  80
  81 static void do_icp_synchronize_state(CPUState *cpu, run_on_cpu_data arg)
  82 {
  83     icp_get_kvm_state(arg.host_ptr);
  84 }
  85
  86 void icp_synchronize_state(ICPState *icp)
  87 {
  88     if (icp->cs) {
  89         run_on_cpu(icp->cs, do_icp_synchronize_state, RUN_ON_CPU_HOST_PTR(icp));
  90     }
  91 }
  92
  93 int icp_set_kvm_state(ICPState *icp)
  94 {
  95     uint64_t state;
  96     int ret;
  97
  98     /* ICP for this CPU thread is not in use, exiting */
  99     if (!icp->cs) {
 100         return 0;
 101     }
 102
 103     state = ((uint64_t)icp->xirr << KVM_REG_PPC_ICP_XISR_SHIFT)
 104         | ((uint64_t)icp->mfrr << KVM_REG_PPC_ICP_MFRR_SHIFT)
 105         | ((uint64_t)icp->pending_priority << KVM_REG_PPC_ICP_PPRI_SHIFT);
 106
 107     ret = kvm_set_one_reg(icp->cs, KVM_REG_PPC_ICP_STATE, &state);
 108     if (ret != 0) {
 109         error_report("Unable to restore KVM interrupt controller state (0x%"
 110                 PRIx64 ") for CPU %ld: %s", state, kvm_arch_vcpu_id(icp->cs),
 111                 strerror(errno));
 112         return ret;
 113     }
 114
 115     return 0;
 116 }
 117
 118 void icp_kvm_realize(DeviceState *dev, Error **errp)
 119 {
 120     ICPState *icp = ICP(dev);
 121     CPUState *cs;
 122     KVMEnabledICP *enabled_icp;
 123     unsigned long vcpu_id;
 124     int ret;
 125
 126     if (kernel_xics_fd == -1) {
 127         abort();
 128     }
 129
 130     cs = icp->cs;
 131     vcpu_id = kvm_arch_vcpu_id(cs);
 132
 133     /*
 134      * If we are reusing a parked vCPU fd corresponding to the CPU
 135      * which was hot-removed earlier we don't have to renable
 136      * KVM_CAP_IRQ_XICS capability again.
 137      */
 138     QLIST_FOREACH(enabled_icp, &kvm_enabled_icps, node) {
 139         if (enabled_icp->vcpu_id == vcpu_id) {
 140             return;
 141         }
 142     }
 143
 144     ret = kvm_vcpu_enable_cap(cs, KVM_CAP_IRQ_XICS, 0, kernel_xics_fd, vcpu_id);
 145     if (ret < 0) {
 146         error_setg(errp, "Unable to connect CPU%ld to kernel XICS: %s", vcpu_id,
 147                    strerror(errno));
 148         return;
 149     }
 150     enabled_icp = g_malloc(sizeof(*enabled_icp));
 151     enabled_icp->vcpu_id = vcpu_id;
 152     QLIST_INSERT_HEAD(&kvm_enabled_icps, enabled_icp, node);
 153 }
 154
 155 /*
 156  * ICS-KVM
 157  */
 158 void ics_get_kvm_state(ICSState *ics)
 159 {
 160     uint64_t state;
 161     int i;
 162
 163     for (i = 0; i < ics->nr_irqs; i++) {
 164         ICSIRQState *irq = &ics->irqs[i];
 165
 166         kvm_device_access(kernel_xics_fd, KVM_DEV_XICS_GRP_SOURCES,
 167                           i + ics->offset, &state, false, &error_fatal);
 168
 169         irq->server = state & KVM_XICS_DESTINATION_MASK;
 170         irq->saved_priority = (state >> KVM_XICS_PRIORITY_SHIFT)
 171             & KVM_XICS_PRIORITY_MASK;
 172         /*
 173          * To be consistent with the software emulation in xics.c, we
 174          * split out the masked state + priority that we get from the
 175          * kernel into 'current priority' (0xff if masked) and
 176          * 'saved priority' (if masked, this is the priority the
 177          * interrupt had before it was masked).  Masking and unmasking
 178          * are done with the ibm,int-off and ibm,int-on RTAS calls.
 179          */
 180         if (state & KVM_XICS_MASKED) {
 181             irq->priority = 0xff;
 182         } else {
 183             irq->priority = irq->saved_priority;
 184         }
 185
 186         irq->status = 0;
 187         if (state & KVM_XICS_PENDING) {
 188             if (state & KVM_XICS_LEVEL_SENSITIVE) {
 189                 irq->status |= XICS_STATUS_ASSERTED;
 190             } else {
 191                 /*
 192                  * A pending edge-triggered interrupt (or MSI)
 193                  * must have been rejected previously when we
 194                  * first detected it and tried to deliver it,
 195                  * so mark it as pending and previously rejected
 196                  * for consistency with how xics.c works.
 197                  */
 198                 irq->status |= XICS_STATUS_MASKED_PENDING
 199                     | XICS_STATUS_REJECTED;
 200             }
 201         }
 202         if (state & KVM_XICS_PRESENTED) {
 203                 irq->status |= XICS_STATUS_PRESENTED;
 204         }
 205         if (state & KVM_XICS_QUEUED) {
 206                 irq->status |= XICS_STATUS_QUEUED;
 207         }
 208     }
 209 }
 210
 211 void ics_synchronize_state(ICSState *ics)
 212 {
 213     ics_get_kvm_state(ics);
 214 }
 215
 216 int ics_set_kvm_state_one(ICSState *ics, int srcno)
 217 {
 218     uint64_t state;
 219     Error *local_err = NULL;
 220     ICSIRQState *irq = &ics->irqs[srcno];
 221     int ret;
 222
 223     state = irq->server;
 224     state |= (uint64_t)(irq->saved_priority & KVM_XICS_PRIORITY_MASK)
 225         << KVM_XICS_PRIORITY_SHIFT;
 226     if (irq->priority != irq->saved_priority) {
 227         assert(irq->priority == 0xff);
 228         state |= KVM_XICS_MASKED;
 229     }
 230
 231     if (irq->flags & XICS_FLAGS_IRQ_LSI) {
 232         state |= KVM_XICS_LEVEL_SENSITIVE;
 233         if (irq->status & XICS_STATUS_ASSERTED) {
 234             state |= KVM_XICS_PENDING;
 235         }
 236     } else {
 237         if (irq->status & XICS_STATUS_MASKED_PENDING) {
 238             state |= KVM_XICS_PENDING;
 239         }
 240     }
 241     if (irq->status & XICS_STATUS_PRESENTED) {
 242         state |= KVM_XICS_PRESENTED;
 243     }
 244     if (irq->status & XICS_STATUS_QUEUED) {
 245         state |= KVM_XICS_QUEUED;
 246     }
 247
 248     ret = kvm_device_access(kernel_xics_fd, KVM_DEV_XICS_GRP_SOURCES,
 249                             srcno + ics->offset, &state, true, &local_err);
 250     if (local_err) {
 251         error_report_err(local_err);
 252         return ret;
 253     }
 254
 255     return 0;
 256 }
 257
 258 int ics_set_kvm_state(ICSState *ics)
 259 {
 260     int i;
 261
 262     for (i = 0; i < ics->nr_irqs; i++) {
 263         int ret;
 264
 265         ret = ics_set_kvm_state_one(ics, i);
 266         if (ret) {
 267             return ret;
 268         }
 269     }
 270
 271     return 0;
 272 }
 273
 274 void ics_kvm_set_irq(ICSState *ics, int srcno, int val)
 275 {
 276     struct kvm_irq_level args;
 277     int rc;
 278
 279     args.irq = srcno + ics->offset;
 280     if (ics->irqs[srcno].flags & XICS_FLAGS_IRQ_MSI) {
 281         if (!val) {
 282             return;
 283         }
 284         args.level = KVM_INTERRUPT_SET;
 285     } else {
 286         args.level = val ? KVM_INTERRUPT_SET_LEVEL : KVM_INTERRUPT_UNSET;
 287     }
 288     rc = kvm_vm_ioctl(kvm_state, KVM_IRQ_LINE, &args);
 289     if (rc < 0) {
 290         perror("kvm_irq_line");
 291     }
 292 }
 293
 294 static void rtas_dummy(PowerPCCPU *cpu, sPAPRMachineState *spapr,
 295                        uint32_t token,
 296                        uint32_t nargs, target_ulong args,
 297                        uint32_t nret, target_ulong rets)
 298 {
 299     error_report("pseries: %s must never be called for in-kernel XICS",
 300                  __func__);
 301 }
 302
 303 int xics_kvm_init(sPAPRMachineState *spapr, Error **errp)
 304 {
 305     int rc;
 306
 307     if (!kvm_enabled() || !kvm_check_extension(kvm_state, KVM_CAP_IRQ_XICS)) {
 308         error_setg(errp,
 309                    "KVM and IRQ_XICS capability must be present for in-kernel XICS");
 310         goto fail;
 311     }
 312
 313     spapr_rtas_register(RTAS_IBM_SET_XIVE, "ibm,set-xive", rtas_dummy);
 314     spapr_rtas_register(RTAS_IBM_GET_XIVE, "ibm,get-xive", rtas_dummy);
 315     spapr_rtas_register(RTAS_IBM_INT_OFF, "ibm,int-off", rtas_dummy);
 316     spapr_rtas_register(RTAS_IBM_INT_ON, "ibm,int-on", rtas_dummy);
 317
 318     rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_SET_XIVE, "ibm,set-xive");
 319     if (rc < 0) {
 320         error_setg(errp, "kvmppc_define_rtas_kernel_token: ibm,set-xive");
 321         goto fail;
 322     }
 323
 324     rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_GET_XIVE, "ibm,get-xive");
 325     if (rc < 0) {
 326         error_setg(errp, "kvmppc_define_rtas_kernel_token: ibm,get-xive");
 327         goto fail;
 328     }
 329
 330     rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_INT_ON, "ibm,int-on");
 331     if (rc < 0) {
 332         error_setg(errp, "kvmppc_define_rtas_kernel_token: ibm,int-on");
 333         goto fail;
 334     }
 335
 336     rc = kvmppc_define_rtas_kernel_token(RTAS_IBM_INT_OFF, "ibm,int-off");
 337     if (rc < 0) {
 338         error_setg(errp, "kvmppc_define_rtas_kernel_token: ibm,int-off");
 339         goto fail;
 340     }
 341
 342     /* Create the KVM XICS device */
 343     rc = kvm_create_device(kvm_state, KVM_DEV_TYPE_XICS, false);
 344     if (rc < 0) {
 345         error_setg_errno(errp, -rc, "Error on KVM_CREATE_DEVICE for XICS");
 346         goto fail;
 347     }
 348
 349     kernel_xics_fd = rc;
 350     kvm_kernel_irqchip = true;
 351     kvm_msi_via_irqfd_allowed = true;
 352     kvm_gsi_direct_mapping = true;
 353
 354     return 0;
 355
 356 fail:
 357     kvmppc_define_rtas_kernel_token(0, "ibm,set-xive");
 358     kvmppc_define_rtas_kernel_token(0, "ibm,get-xive");
 359     kvmppc_define_rtas_kernel_token(0, "ibm,int-on");
 360     kvmppc_define_rtas_kernel_token(0, "ibm,int-off");
 361     return -1;
 362 }