target-arm/kvm64.c

   1 /*
   2  * ARM implementation of KVM hooks, 64 bit specific code
   3  *
   4  * Copyright Mian-M. Hamayun 2013, Virtual Open Systems
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
   7  * See the COPYING file in the top-level directory.
   8  *
   9  */
  10
  11 #include <stdio.h>
  12 #include <sys/types.h>
  13 #include <sys/ioctl.h>
  14 #include <sys/mman.h>
  15
  16 #include <linux/kvm.h>
  17
  18 #include "qemu-common.h"
  19 #include "qemu/timer.h"
  20 #include "sysemu/sysemu.h"
  21 #include "sysemu/kvm.h"
  22 #include "kvm_arm.h"
  23 #include "cpu.h"
  24 #include "hw/arm/arm.h"
  25
  26 static inline void set_feature(uint64_t *features, int feature)
  27 {
  28     *features |= 1ULL << feature;
  29 }
  30
  31 bool kvm_arm_get_host_cpu_features(ARMHostCPUClass *ahcc)
  32 {
  33     /* Identify the feature bits corresponding to the host CPU, and
  34      * fill out the ARMHostCPUClass fields accordingly. To do this
  35      * we have to create a scratch VM, create a single CPU inside it,
  36      * and then query that CPU for the relevant ID registers.
  37      * For AArch64 we currently don't care about ID registers at
  38      * all; we just want to know the CPU type.
  39      */
  40     int fdarray[3];
  41     uint64_t features = 0;
  42     /* Old kernels may not know about the PREFERRED_TARGET ioctl: however
  43      * we know these will only support creating one kind of guest CPU,
  44      * which is its preferred CPU type. Fortunately these old kernels
  45      * support only a very limited number of CPUs.
  46      */
  47     static const uint32_t cpus_to_try[] = {
  48         KVM_ARM_TARGET_AEM_V8,
  49         KVM_ARM_TARGET_FOUNDATION_V8,
  50         KVM_ARM_TARGET_CORTEX_A57,
  51         QEMU_KVM_ARM_TARGET_NONE
  52     };
  53     struct kvm_vcpu_init init;
  54
  55     if (!kvm_arm_create_scratch_host_vcpu(cpus_to_try, fdarray, &init)) {
  56         return false;
  57     }
  58
  59     ahcc->target = init.target;
  60     ahcc->dtb_compatible = "arm,arm-v8";
  61
  62     kvm_arm_destroy_scratch_host_vcpu(fdarray);
  63
  64    /* We can assume any KVM supporting CPU is at least a v8
  65      * with VFPv4+Neon; this in turn implies most of the other
  66      * feature bits.
  67      */
  68     set_feature(&features, ARM_FEATURE_V8);
  69     set_feature(&features, ARM_FEATURE_VFP4);
  70     set_feature(&features, ARM_FEATURE_NEON);
  71     set_feature(&features, ARM_FEATURE_AARCH64);
  72
  73     ahcc->features = features;
  74
  75     return true;
  76 }
  77
  78 int kvm_arch_init_vcpu(CPUState *cs)
  79 {
  80     ARMCPU *cpu = ARM_CPU(cs);
  81     struct kvm_vcpu_init init;
  82     int ret;
  83
  84     if (cpu->kvm_target == QEMU_KVM_ARM_TARGET_NONE ||
  85         !arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) {
  86         fprintf(stderr, "KVM is not supported for this guest CPU type\n");
  87         return -EINVAL;
  88     }
  89
  90     init.target = cpu->kvm_target;
  91     memset(init.features, 0, sizeof(init.features));
  92     if (cpu->start_powered_off) {
  93         init.features[0] = 1 << KVM_ARM_VCPU_POWER_OFF;
  94     }
  95     ret = kvm_vcpu_ioctl(cs, KVM_ARM_VCPU_INIT, &init);
  96
  97     /* TODO : support for save/restore/reset of system regs via tuple list */
  98
  99     return ret;
 100 }
 101
 102 #define AARCH64_CORE_REG(x)   (KVM_REG_ARM64 | KVM_REG_SIZE_U64 | \
 103                  KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(x))
 104
 105 int kvm_arch_put_registers(CPUState *cs, int level)
 106 {
 107     struct kvm_one_reg reg;
 108     uint64_t val;
 109     int i;
 110     int ret;
 111
 112     ARMCPU *cpu = ARM_CPU(cs);
 113     CPUARMState *env = &cpu->env;
 114
 115     for (i = 0; i < 31; i++) {
 116         reg.id = AARCH64_CORE_REG(regs.regs[i]);
 117         reg.addr = (uintptr_t) &env->xregs[i];
 118         ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
 119         if (ret) {
 120             return ret;
 121         }
 122     }
 123
 124     /* KVM puts SP_EL0 in regs.sp and SP_EL1 in regs.sp_el1. On the
 125      * QEMU side we keep the current SP in xregs[31] as well.
 126      */
 127     if (env->pstate & PSTATE_SP) {
 128         env->sp_el[1] = env->xregs[31];
 129     } else {
 130         env->sp_el[0] = env->xregs[31];
 131     }
 132
 133     reg.id = AARCH64_CORE_REG(regs.sp);
 134     reg.addr = (uintptr_t) &env->sp_el[0];
 135     ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
 136     if (ret) {
 137         return ret;
 138     }
 139
 140     reg.id = AARCH64_CORE_REG(sp_el1);
 141     reg.addr = (uintptr_t) &env->sp_el[1];
 142     ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
 143     if (ret) {
 144         return ret;
 145     }
 146
 147     /* Note that KVM thinks pstate is 64 bit but we use a uint32_t */
 148     val = pstate_read(env);
 149     reg.id = AARCH64_CORE_REG(regs.pstate);
 150     reg.addr = (uintptr_t) &val;
 151     ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
 152     if (ret) {
 153         return ret;
 154     }
 155
 156     reg.id = AARCH64_CORE_REG(regs.pc);
 157     reg.addr = (uintptr_t) &env->pc;
 158     ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
 159     if (ret) {
 160         return ret;
 161     }
 162
 163     reg.id = AARCH64_CORE_REG(elr_el1);
 164     reg.addr = (uintptr_t) &env->elr_el1;
 165     ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
 166     if (ret) {
 167         return ret;
 168     }
 169
 170     for (i = 0; i < KVM_NR_SPSR; i++) {
 171         reg.id = AARCH64_CORE_REG(spsr[i]);
 172         reg.addr = (uintptr_t) &env->banked_spsr[i - 1];
 173         ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
 174         if (ret) {
 175             return ret;
 176         }
 177     }
 178
 179     /* TODO:
 180      * FP state
 181      * system registers
 182      */
 183     return ret;
 184 }
 185
 186 int kvm_arch_get_registers(CPUState *cs)
 187 {
 188     struct kvm_one_reg reg;
 189     uint64_t val;
 190     int i;
 191     int ret;
 192
 193     ARMCPU *cpu = ARM_CPU(cs);
 194     CPUARMState *env = &cpu->env;
 195
 196     for (i = 0; i < 31; i++) {
 197         reg.id = AARCH64_CORE_REG(regs.regs[i]);
 198         reg.addr = (uintptr_t) &env->xregs[i];
 199         ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 200         if (ret) {
 201             return ret;
 202         }
 203     }
 204
 205     reg.id = AARCH64_CORE_REG(regs.sp);
 206     reg.addr = (uintptr_t) &env->sp_el[0];
 207     ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 208     if (ret) {
 209         return ret;
 210     }
 211
 212     reg.id = AARCH64_CORE_REG(sp_el1);
 213     reg.addr = (uintptr_t) &env->sp_el[1];
 214     ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 215     if (ret) {
 216         return ret;
 217     }
 218
 219     reg.id = AARCH64_CORE_REG(regs.pstate);
 220     reg.addr = (uintptr_t) &val;
 221     ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 222     if (ret) {
 223         return ret;
 224     }
 225     pstate_write(env, val);
 226
 227     /* KVM puts SP_EL0 in regs.sp and SP_EL1 in regs.sp_el1. On the
 228      * QEMU side we keep the current SP in xregs[31] as well.
 229      */
 230     if (env->pstate & PSTATE_SP) {
 231         env->xregs[31] = env->sp_el[1];
 232     } else {
 233         env->xregs[31] = env->sp_el[0];
 234     }
 235
 236     reg.id = AARCH64_CORE_REG(regs.pc);
 237     reg.addr = (uintptr_t) &env->pc;
 238     ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 239     if (ret) {
 240         return ret;
 241     }
 242
 243     reg.id = AARCH64_CORE_REG(elr_el1);
 244     reg.addr = (uintptr_t) &env->elr_el1;
 245     ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 246     if (ret) {
 247         return ret;
 248     }
 249
 250     for (i = 0; i < KVM_NR_SPSR; i++) {
 251         reg.id = AARCH64_CORE_REG(spsr[i]);
 252         reg.addr = (uintptr_t) &env->banked_spsr[i - 1];
 253         ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 254         if (ret) {
 255             return ret;
 256         }
 257     }
 258
 259     /* TODO: other registers */
 260     return ret;
 261 }
 262
 263 void kvm_arch_reset_vcpu(CPUState *cs)
 264 {
 265 }