From: Rob Herring <rob.herr...@linaro.org> Add support for handling PSCI calls in system emulation. Both version 0.1 and 0.2 of the PSCI spec are supported. Platforms can enable support by setting "psci-method" QOM property on the cpus to SMC or HVC emulation and having PSCI binding in their dtb.
Signed-off-by: Rob Herring <rob.herr...@linaro.org> --- v2: - Add reference to PSCI spec - Add target_cs instead of cs when doing operations on a different core. - Move arm_cpu_do_hvc/smc contents from previous patch. - Set context_id on both x0 and r0. target-arm/Makefile.objs | 2 +- target-arm/cpu-qom.h | 6 ++ target-arm/cpu.c | 1 + target-arm/helper.c | 12 ++++ target-arm/kvm-consts.h | 6 ++ target-arm/psci.c | 157 +++++++++++++++++++++++++++++++++++++++++++++++ 6 files changed, 183 insertions(+), 1 deletion(-) create mode 100644 target-arm/psci.c diff --git a/target-arm/Makefile.objs b/target-arm/Makefile.objs index dcd167e..50f6c43 100644 --- a/target-arm/Makefile.objs +++ b/target-arm/Makefile.objs @@ -1,5 +1,5 @@ obj-y += arm-semi.o -obj-$(CONFIG_SOFTMMU) += machine.o +obj-$(CONFIG_SOFTMMU) += machine.o psci.o obj-$(CONFIG_KVM) += kvm.o obj-$(call land,$(CONFIG_KVM),$(call lnot,$(TARGET_AARCH64))) += kvm32.o obj-$(call land,$(CONFIG_KVM),$(TARGET_AARCH64)) += kvm64.o diff --git a/target-arm/cpu-qom.h b/target-arm/cpu-qom.h index d2ff087..56999f1 100644 --- a/target-arm/cpu-qom.h +++ b/target-arm/cpu-qom.h @@ -105,6 +105,11 @@ typedef struct ARMCPU { /* CPU currently in PSCI powered-off state */ bool powered_off; + /* PSCI emulation state + * 0 - disabled, 1 - smc, 2 - hvc + */ + uint32_t psci_method; + /* [QEMU_]KVM_ARM_TARGET_* constant for this CPU, or * QEMU_KVM_ARM_TARGET_NONE if the kernel doesn't support this CPU type. */ @@ -195,6 +200,7 @@ extern const struct VMStateDescription vmstate_arm_cpu; void register_cp_regs_for_features(ARMCPU *cpu); void init_cpreg_list(ARMCPU *cpu); +bool arm_handle_psci(CPUState *cs); bool arm_cpu_do_hvc(CPUState *cs); bool arm_cpu_do_smc(CPUState *cs); diff --git a/target-arm/cpu.c b/target-arm/cpu.c index a0f9916..64f1157 100644 --- a/target-arm/cpu.c +++ b/target-arm/cpu.c @@ -1024,6 +1024,7 @@ static const ARMCPUInfo arm_cpus[] = { static Property arm_cpu_properties[] = { DEFINE_PROP_BOOL("start-powered-off", ARMCPU, start_powered_off, false), + DEFINE_PROP_UINT32("psci-method", ARMCPU, psci_method, 0), DEFINE_PROP_UINT32("midr", ARMCPU, midr, 0), DEFINE_PROP_END_OF_LIST() }; diff --git a/target-arm/helper.c b/target-arm/helper.c index 552e601..c1be201 100644 --- a/target-arm/helper.c +++ b/target-arm/helper.c @@ -3257,11 +3257,23 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) bool arm_cpu_do_hvc(CPUState *cs) { + ARMCPU *cpu = ARM_CPU(cs); + + if (cpu->psci_method == QEMU_PSCI_METHOD_HVC) { + return arm_handle_psci(cs); + } + return false; } bool arm_cpu_do_smc(CPUState *cs) { + ARMCPU *cpu = ARM_CPU(cs); + + if (cpu->psci_method == QEMU_PSCI_METHOD_SMC) { + return arm_handle_psci(cs); + } + return false; } diff --git a/target-arm/kvm-consts.h b/target-arm/kvm-consts.h index 6009a33..d25b9b8 100644 --- a/target-arm/kvm-consts.h +++ b/target-arm/kvm-consts.h @@ -50,6 +50,12 @@ MISMATCH_CHECK(PSCI_FN_CPU_OFF, KVM_PSCI_FN_CPU_OFF) MISMATCH_CHECK(PSCI_FN_CPU_ON, KVM_PSCI_FN_CPU_ON) MISMATCH_CHECK(PSCI_FN_MIGRATE, KVM_PSCI_FN_MIGRATE) +enum { + QEMU_PSCI_METHOD_DISABLED = 0, + QEMU_PSCI_METHOD_SMC = 1, + QEMU_PSCI_METHOD_HVC = 2, +}; + /* Note that KVM uses overlapping values for AArch32 and AArch64 * target CPU numbers. AArch32 targets: */ diff --git a/target-arm/psci.c b/target-arm/psci.c new file mode 100644 index 0000000..88af3f9 --- /dev/null +++ b/target-arm/psci.c @@ -0,0 +1,157 @@ +/* + * Copyright (C) 2014 - Linaro + * Author: Rob Herring <rob.herr...@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ +#include <cpu.h> +#include <cpu-qom.h> +#include <kvm-consts.h> +#include <sysemu/sysemu.h> +#include <linux/psci.h> + +/* + * This function implements emulation of ARM Power State Coordination + * Interface (PSCI) version 0.2. Details of the PSCI functionality can be + * found at: + * http://infocenter.arm.com/help//topic/com.arm.doc.den0022b/index.html + */ +bool arm_handle_psci(CPUState *cs) +{ + CPUState *target_cs; + CPUClass *cc; + ARMCPU *cpu = ARM_CPU(cs); + 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++) { + /* Zero extending registers on 32-bit is okay for PSCI */ + param[i] = is_a64(env) ? env->xregs[i] : env->regs[i]; + } + + if ((param[0] & PSCI_0_2_64BIT) && !is_a64(env)) { + ret = PSCI_RET_INVALID_PARAMS; + goto err; + } + + switch (param[0]) { + case PSCI_0_2_FN_PSCI_VERSION: + ret = PSCI_VERSION_MAJOR(0) | PSCI_VERSION_MINOR(2); + break; + case PSCI_0_2_FN_MIGRATE_INFO_TYPE: + ret = PSCI_0_2_TOS_MP; /* No trusted OS */ + break; + case PSCI_0_2_FN_AFFINITY_INFO: + case PSCI_0_2_FN64_AFFINITY_INFO: + mpidr = param[1]; + + switch (param[2]) { + case 0: + /* Get the target cpu */ + target_cs = qemu_get_cpu(mpidr & 0xff); + if (!target_cs) { + ret = PSCI_RET_INVALID_PARAMS; + break; + } + cpu = ARM_CPU(target_cs); + ret = cpu->powered_off ? 1 : 0; + break; + default: + /* Everything above affinity level 0 is always on. */ + ret = 0; + } + break; + case PSCI_0_2_FN_SYSTEM_RESET: + qemu_system_reset_request(); + break; + case PSCI_0_2_FN_SYSTEM_OFF: + qemu_system_powerdown_request(); + break; + case PSCI_FN_CPU_ON: + case PSCI_0_2_FN_CPU_ON: + case PSCI_0_2_FN64_CPU_ON: + mpidr = param[1]; + entry = param[2]; + context_id = param[3]; + + /* change to the cpu we are powering up */ + target_cs = qemu_get_cpu(mpidr & 0xff); + if (!target_cs) { + ret = PSCI_RET_INVALID_PARAMS; + break; + } + cpu = ARM_CPU(target_cs); + + if (!cpu->powered_off) { + ret = PSCI_RET_ALREADY_ON; + break; + } + + /* Initialize the cpu we are turning on */ + cpu_reset(target_cs); + cc = CPU_GET_CLASS(target_cs); + cc->set_pc(target_cs, entry); + + cpu->powered_off = false; + target_cs->interrupt_request |= CPU_INTERRUPT_EXITTB; + + /* Set the context_id in r0/x0 */ + cpu->env.xregs[0] = cpu->env.regs[0] = context_id; + + ret = 0; + break; + case PSCI_FN_CPU_OFF: + case PSCI_0_2_FN_CPU_OFF: + cpu->powered_off = true; + cs->exit_request = 1; + cs->halted = 1; + + /* CPU_OFF should never return, but if it does return an error */ + ret = PSCI_RET_DENIED; + break; + case PSCI_FN_CPU_SUSPEND: + case PSCI_0_2_FN_CPU_SUSPEND: + case PSCI_0_2_FN64_CPU_SUSPEND: + /* Affinity levels are not supported in QEMU */ + if (param[1] & 0xfffe0000) { + ret = PSCI_RET_INVALID_PARAMS; + break; + } + /* Powerdown is not supported, we always go into WFI */ + cs->halted = 1; + cs->exit_request = 1; + + /* Return success when we wakeup */ + ret = 0; + break; + case PSCI_FN_MIGRATE: + case PSCI_0_2_FN_MIGRATE: + ret = PSCI_RET_NOT_SUPPORTED; + break; + default: + return false; + } + +err: + if (is_a64(env)) { + env->xregs[0] = ret; + } else { + env->regs[0] = ret; + } + return true; +} -- 1.9.1