void arm_handle_psci_call(ARMCPU *cpu) { /* * This function partially implements the logic for dispatching Power State * Coordination Interface (PSCI) calls (as described in ARM DEN 0022B.b), * to the extent required for bringing up and taking down secondary cores, * and for handling reset and poweroff requests. * Additional information about the calling convention used is available in * the document 'SMC Calling Convention' (ARM DEN 0028) */ CPUARMState *env = &cpu->env; uint64_t param[4]; uint64_t context_id, mpidr; target_ulong entry; int32_t ret = 0; int i; for (i = 0; i < 4; i++) { /* * All PSCI functions take explicit 32-bit or native int sized * arguments so we can simply zero-extend all arguments regardless * of which exact function we are about to call. */ param[i] = is_a64(env) ? env->xregs[i] : env->regs[i]; } if ((param[0] & QEMU_PSCI_0_2_64BIT) && !is_a64(env)) { ret = QEMU_PSCI_RET_INVALID_PARAMS; goto err; } switch (param[0]) { CPUState *target_cpu_state; ARMCPU *target_cpu; case QEMU_PSCI_0_2_FN_PSCI_VERSION: ret = QEMU_PSCI_0_2_RET_VERSION_0_2; break; case QEMU_PSCI_0_2_FN_MIGRATE_INFO_TYPE: ret = QEMU_PSCI_0_2_RET_TOS_MIGRATION_NOT_REQUIRED; /* No trusted OS */ break; case QEMU_PSCI_0_2_FN_AFFINITY_INFO: case QEMU_PSCI_0_2_FN64_AFFINITY_INFO: mpidr = param[1]; switch (param[2]) { case 0: target_cpu_state = arm_get_cpu_by_id(mpidr); if (!target_cpu_state) { ret = QEMU_PSCI_RET_INVALID_PARAMS; break; } target_cpu = ARM_CPU(target_cpu_state); ret = target_cpu->powered_off ? 1 : 0; break; default: /* Everything above affinity level 0 is always on. */ ret = 0; } break; case QEMU_PSCI_0_2_FN_SYSTEM_RESET: qemu_system_reset_request(); /* QEMU reset and shutdown are async requests, but PSCI * mandates that we never return from the reset/shutdown * call, so power the CPU off now so it doesn't execute * anything further. */ goto cpu_off; case QEMU_PSCI_0_2_FN_SYSTEM_OFF: qemu_system_shutdown_request(); goto cpu_off; case QEMU_PSCI_0_1_FN_CPU_ON: case QEMU_PSCI_0_2_FN_CPU_ON: case QEMU_PSCI_0_2_FN64_CPU_ON: { /* The PSCI spec mandates that newly brought up CPUs start * in the highest exception level which exists and is enabled * on the calling CPU. Since the QEMU PSCI implementation is * acting as a "fake EL3" or "fake EL2" firmware, this for us * means that we want to start at the highest NS exception level * that we are providing to the guest. * The execution mode should be that which is currently in use * by the same exception level on the calling CPU. * The CPU should be started with the context_id value * in x0 (if AArch64) or r0 (if AArch32). */ int target_el = arm_feature(env, ARM_FEATURE_EL2) ? 2 : 1; bool target_aarch64 = arm_el_is_aa64(env, target_el); mpidr = param[1]; entry = param[2]; context_id = param[3]; ret = arm_set_cpu_on(mpidr, entry, context_id, target_el, target_aarch64); break; } case QEMU_PSCI_0_1_FN_CPU_OFF: case QEMU_PSCI_0_2_FN_CPU_OFF: goto cpu_off; case QEMU_PSCI_0_1_FN_CPU_SUSPEND: case QEMU_PSCI_0_2_FN_CPU_SUSPEND: case QEMU_PSCI_0_2_FN64_CPU_SUSPEND: /* Affinity levels are not supported in QEMU */ if (param[1] & 0xfffe0000) { ret = QEMU_PSCI_RET_INVALID_PARAMS; break; } /* Powerdown is not supported, we always go into WFI */ if (is_a64(env)) { env->xregs[0] = 0; } else { env->regs[0] = 0; } helper_wfi(env); break; case QEMU_PSCI_0_1_FN_MIGRATE: case QEMU_PSCI_0_2_FN_MIGRATE: ret = QEMU_PSCI_RET_NOT_SUPPORTED; break; default: g_assert_not_reached(); } err: if (is_a64(env)) { env->xregs[0] = ret; } else { env->regs[0] = ret; } return; cpu_off: ret = arm_set_cpu_off(cpu->mp_affinity); /* notreached */ /* sanity check in case something failed */ assert(ret == QEMU_ARM_POWERCTL_RET_SUCCESS); }