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     reg.id = AARCH64_CORE_REG(regs.sp);
 125     reg.addr = (uintptr_t) &env->xregs[31];
 126     ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
 127     if (ret) {
 128         return ret;
 129     }
 130
 131     /* Note that KVM thinks pstate is 64 bit but we use a uint32_t */
 132     val = pstate_read(env);
 133     reg.id = AARCH64_CORE_REG(regs.pstate);
 134     reg.addr = (uintptr_t) &val;
 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(regs.pc);
 141     reg.addr = (uintptr_t) &env->pc;
 142     ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
 143     if (ret) {
 144         return ret;
 145     }
 146
 147     /* TODO:
 148      * SP_EL1
 149      * ELR_EL1
 150      * SPSR[]
 151      * FP state
 152      * system registers
 153      */
 154     return ret;
 155 }
 156
 157 int kvm_arch_get_registers(CPUState *cs)
 158 {
 159     struct kvm_one_reg reg;
 160     uint64_t val;
 161     int i;
 162     int ret;
 163
 164     ARMCPU *cpu = ARM_CPU(cs);
 165     CPUARMState *env = &cpu->env;
 166
 167     for (i = 0; i < 31; i++) {
 168         reg.id = AARCH64_CORE_REG(regs.regs[i]);
 169         reg.addr = (uintptr_t) &env->xregs[i];
 170         ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 171         if (ret) {
 172             return ret;
 173         }
 174     }
 175
 176     reg.id = AARCH64_CORE_REG(regs.sp);
 177     reg.addr = (uintptr_t) &env->xregs[31];
 178     ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 179     if (ret) {
 180         return ret;
 181     }
 182
 183     reg.id = AARCH64_CORE_REG(regs.pstate);
 184     reg.addr = (uintptr_t) &val;
 185     ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 186     if (ret) {
 187         return ret;
 188     }
 189     pstate_write(env, val);
 190
 191     reg.id = AARCH64_CORE_REG(regs.pc);
 192     reg.addr = (uintptr_t) &env->pc;
 193     ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
 194     if (ret) {
 195         return ret;
 196     }
 197
 198     /* TODO: other registers */
 199     return ret;
 200 }
 201
 202 void kvm_arch_reset_vcpu(CPUState *cs)
 203 {
 204 }