From patchwork Thu Oct 9 14:30:27 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Maydell X-Patchwork-Id: 398057 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id E017E1400B5 for ; Fri, 10 Oct 2014 01:33:26 +1100 (EST) Received: from localhost ([::1]:42879 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XcEmS-0003hN-L4 for incoming@patchwork.ozlabs.org; Thu, 09 Oct 2014 10:33:24 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56285) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XcEjv-0007cE-DI for qemu-devel@nongnu.org; Thu, 09 Oct 2014 10:30:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XcEjo-0006yi-IK for qemu-devel@nongnu.org; Thu, 09 Oct 2014 10:30:47 -0400 Received: from mnementh.archaic.org.uk ([2001:8b0:1d0::1]:54165) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XcEjo-0006ur-6J for qemu-devel@nongnu.org; Thu, 09 Oct 2014 10:30:40 -0400 Received: from pm215 by mnementh.archaic.org.uk with local (Exim 4.80) (envelope-from ) id 1XcEjc-0004ck-E1; Thu, 09 Oct 2014 15:30:28 +0100 From: Peter Maydell To: qemu-devel@nongnu.org Date: Thu, 9 Oct 2014 15:30:27 +0100 Message-Id: <1412865028-17725-7-git-send-email-peter.maydell@linaro.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1412865028-17725-1-git-send-email-peter.maydell@linaro.org> References: <1412865028-17725-1-git-send-email-peter.maydell@linaro.org> X-detected-operating-system: by eggs.gnu.org: Error: Malformed IPv6 address (bad octet value). X-Received-From: 2001:8b0:1d0::1 Cc: Greg Bellows , Ard Biesheuvel , patches@linaro.org Subject: [Qemu-devel] [PATCH v5 6/7] target-arm: add emulation of PSCI calls for system emulation X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Rob Herring 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 the "psci-conduit" QOM property on the cpus to SMC or HVC emulation and having a PSCI binding in their dtb. Signed-off-by: Rob Herring Signed-off-by: Ard Biesheuvel [PMM: made system reset/off PSCI functions power down the CPU so we obey the PSCI API requirement never to return from them; rearranged how the code is plumbed into the exception system, so that we split "is this a valid call?" from "do the call"] Signed-off-by: Peter Maydell --- target-arm/Makefile.objs | 1 + target-arm/cpu-qom.h | 5 + target-arm/cpu.c | 10 +- target-arm/cpu.h | 6 ++ target-arm/helper-a64.c | 6 ++ target-arm/helper.c | 6 ++ target-arm/internals.h | 12 +++ target-arm/op_helper.c | 16 ++++ target-arm/psci.c | 242 +++++++++++++++++++++++++++++++++++++++++++++++ 9 files changed, 301 insertions(+), 3 deletions(-) create mode 100644 target-arm/psci.c diff --git a/target-arm/Makefile.objs b/target-arm/Makefile.objs index dcd167e..9460b40 100644 --- a/target-arm/Makefile.objs +++ b/target-arm/Makefile.objs @@ -7,5 +7,6 @@ obj-$(call lnot,$(CONFIG_KVM)) += kvm-stub.o obj-y += translate.o op_helper.o helper.o cpu.o obj-y += neon_helper.o iwmmxt_helper.o obj-y += gdbstub.o +obj-$(CONFIG_SOFTMMU) += psci.o obj-$(TARGET_AARCH64) += cpu64.o translate-a64.o helper-a64.o gdbstub64.o obj-y += crypto_helper.o diff --git a/target-arm/cpu-qom.h b/target-arm/cpu-qom.h index aeb7e1d..dcfda7d 100644 --- a/target-arm/cpu-qom.h +++ b/target-arm/cpu-qom.h @@ -101,6 +101,11 @@ typedef struct ARMCPU { /* CPU currently in PSCI powered-off state */ bool powered_off; + /* PSCI conduit used to invoke PSCI methods + * 0 - disabled, 1 - smc, 2 - hvc + */ + uint32_t psci_conduit; + /* [QEMU_]KVM_ARM_TARGET_* constant for this CPU, or * QEMU_KVM_ARM_TARGET_NONE if the kernel doesn't support this CPU type. */ diff --git a/target-arm/cpu.c b/target-arm/cpu.c index 2061cb7..e837f64 100644 --- a/target-arm/cpu.c +++ b/target-arm/cpu.c @@ -334,9 +334,12 @@ static void arm_cpu_initfn(Object *obj) cpu->psci_version = 1; /* By default assume PSCI v0.1 */ cpu->kvm_target = QEMU_KVM_ARM_TARGET_NONE; - if (tcg_enabled() && !inited) { - inited = true; - arm_translate_init(); + if (tcg_enabled()) { + cpu->psci_version = 2; /* TCG implements PSCI 0.2 */ + if (!inited) { + inited = true; + arm_translate_init(); + } } } @@ -1090,6 +1093,7 @@ 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-conduit", ARMCPU, psci_conduit, 0), DEFINE_PROP_UINT32("midr", ARMCPU, midr, 0), DEFINE_PROP_END_OF_LIST() }; diff --git a/target-arm/cpu.h b/target-arm/cpu.h index 65a3417..690686c 100644 --- a/target-arm/cpu.h +++ b/target-arm/cpu.h @@ -1484,4 +1484,10 @@ static inline void cpu_pc_from_tb(CPUARMState *env, TranslationBlock *tb) } } +enum { + QEMU_PSCI_CONDUIT_DISABLED = 0, + QEMU_PSCI_CONDUIT_SMC = 1, + QEMU_PSCI_CONDUIT_HVC = 2, +}; + #endif diff --git a/target-arm/helper-a64.c b/target-arm/helper-a64.c index 7ae84f6..daf5adc 100644 --- a/target-arm/helper-a64.c +++ b/target-arm/helper-a64.c @@ -468,6 +468,12 @@ void aarch64_cpu_do_interrupt(CPUState *cs) env->exception.syndrome); } + if (arm_is_psci_call(cpu, cs->exception_index)) { + arm_handle_psci_call(cpu); + qemu_log_mask(CPU_LOG_INT, "...handled as PSCI call\n"); + return; + } + switch (cs->exception_index) { case EXCP_PREFETCH_ABORT: case EXCP_DATA_ABORT: diff --git a/target-arm/helper.c b/target-arm/helper.c index 497178a..d837820 100644 --- a/target-arm/helper.c +++ b/target-arm/helper.c @@ -3970,6 +3970,12 @@ void arm_cpu_do_interrupt(CPUState *cs) arm_log_exception(cs->exception_index); + if (arm_is_psci_call(cpu, cs->exception_index)) { + arm_handle_psci_call(cpu); + qemu_log_mask(CPU_LOG_INT, "...handled as PSCI call\n"); + return; + } + /* If this is a debug exception we must update the DBGDSCR.MOE bits */ switch (env->exception.syndrome >> ARM_EL_EC_SHIFT) { case EC_BREAKPOINT: diff --git a/target-arm/internals.h b/target-arm/internals.h index e46de71..51c5c16 100644 --- a/target-arm/internals.h +++ b/target-arm/internals.h @@ -366,4 +366,16 @@ void hw_breakpoint_update_all(ARMCPU *cpu); /* Callback function for when a watchpoint or breakpoint triggers. */ void arm_debug_excp_handler(CPUState *cs); +#ifdef CONFIG_USER_ONLY +static inline bool arm_is_psci_call(ARMCPU *cpu, int excp_type) +{ + return false; +} +#else +/* Return true if the r0/x0 value indicates that this SMC/HVC is a PSCI call. */ +bool arm_is_psci_call(ARMCPU *cpu, int excp_type); +/* Actually handle a PSCI call */ +void arm_handle_psci_call(ARMCPU *cpu); +#endif + #endif diff --git a/target-arm/op_helper.c b/target-arm/op_helper.c index 5652096..464a5ce 100644 --- a/target-arm/op_helper.c +++ b/target-arm/op_helper.c @@ -387,11 +387,19 @@ void HELPER(clear_pstate_ss)(CPUARMState *env) void HELPER(pre_hvc)(CPUARMState *env) { + ARMCPU *cpu = arm_env_get_cpu(env); int cur_el = arm_current_pl(env); /* FIXME: Use actual secure state. */ bool secure = false; bool undef; + if (arm_is_psci_call(cpu, EXCP_HVC)) { + /* If PSCI is enabled and this looks like a valid PSCI call then + * that overrides the architecturally mandated HVC behaviour. + */ + return; + } + if (!arm_feature(env, ARM_FEATURE_EL2)) { /* If EL2 doesn't exist, HVC always UNDEFs */ undef = true; @@ -419,6 +427,7 @@ void HELPER(pre_hvc)(CPUARMState *env) void HELPER(pre_smc)(CPUARMState *env, uint32_t syndrome) { + ARMCPU *cpu = arm_env_get_cpu(env); int cur_el = arm_current_pl(env); /* FIXME: Use real secure state. */ bool secure = false; @@ -430,6 +439,13 @@ void HELPER(pre_smc)(CPUARMState *env, uint32_t syndrome) */ bool undef = is_a64(env) ? smd : (!secure && smd); + if (arm_is_psci_call(cpu, EXCP_SMC)) { + /* If PSCI is enabled and this looks like a valid PSCI call then + * that overrides the architecturally mandated SMC behaviour. + */ + return; + } + if (!arm_feature(env, ARM_FEATURE_EL3)) { /* If we have no EL3 then SMC always UNDEFs */ undef = true; diff --git a/target-arm/psci.c b/target-arm/psci.c new file mode 100644 index 0000000..d8fafab --- /dev/null +++ b/target-arm/psci.c @@ -0,0 +1,242 @@ +/* + * Copyright (C) 2014 - Linaro + * Author: Rob Herring + * + * 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 . + */ +#include +#include +#include +#include +#include +#include "internals.h" + +bool arm_is_psci_call(ARMCPU *cpu, int excp_type) +{ + /* Return true if the r0/x0 value indicates a PSCI call and + * the exception type matches the configured PSCI conduit. This is + * called before the SMC/HVC instruction is executed, to decide whether + * we should treat it as a PSCI call or with the architecturally + * defined behaviour for an SMC or HVC (which might be UNDEF or trap + * to EL2 or to EL3). + */ + CPUARMState *env = &cpu->env; + uint64_t param = is_a64(env) ? env->xregs[0] : env->regs[0]; + + switch (excp_type) { + case EXCP_HVC: + if (cpu->psci_conduit != QEMU_PSCI_CONDUIT_HVC) { + return false; + } + break; + case EXCP_SMC: + if (cpu->psci_conduit != QEMU_PSCI_CONDUIT_SMC) { + return false; + } + break; + default: + return false; + } + + switch (param) { + case QEMU_PSCI_0_2_FN_PSCI_VERSION: + case QEMU_PSCI_0_2_FN_MIGRATE_INFO_TYPE: + case QEMU_PSCI_0_2_FN_AFFINITY_INFO: + case QEMU_PSCI_0_2_FN64_AFFINITY_INFO: + case QEMU_PSCI_0_2_FN_SYSTEM_RESET: + case QEMU_PSCI_0_2_FN_SYSTEM_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: + case QEMU_PSCI_0_1_FN_CPU_OFF: + case QEMU_PSCI_0_2_FN_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: + case QEMU_PSCI_0_1_FN_MIGRATE: + case QEMU_PSCI_0_2_FN_MIGRATE: + return true; + default: + return false; + } +} + +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) + */ + CPUState *cs = CPU(cpu); + 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; + CPUClass *target_cpu_class; + + 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 = qemu_get_cpu(mpidr & 0xff); + 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: + mpidr = param[1]; + entry = param[2]; + context_id = param[3]; + + /* change to the cpu we are powering up */ + target_cpu_state = qemu_get_cpu(mpidr & 0xff); + if (!target_cpu_state) { + ret = QEMU_PSCI_RET_INVALID_PARAMS; + break; + } + target_cpu = ARM_CPU(target_cpu_state); + if (!target_cpu->powered_off) { + ret = QEMU_PSCI_RET_ALREADY_ON; + break; + } + target_cpu_class = CPU_GET_CLASS(target_cpu); + + /* Initialize the cpu we are turning on */ + cpu_reset(target_cpu_state); + target_cpu->powered_off = false; + target_cpu_state->halted = 0; + + /* + * The PSCI spec mandates that newly brought up CPUs enter the + * exception level of the caller in the same execution mode as + * the caller, with context_id in x0/r0, respectively. + * + * For now, it is sufficient to assert() that CPUs come out of + * reset in the same mode as the calling CPU, since we only + * implement EL1, which means that + * (a) there is no EL2 for the calling CPU to trap into to change + * its state + * (b) the newly brought up CPU enters EL1 immediately after coming + * out of reset in the default state + */ + assert(is_a64(env) == is_a64(&target_cpu->env)); + if (is_a64(env)) { + if (entry & 1) { + ret = QEMU_PSCI_RET_INVALID_PARAMS; + break; + } + target_cpu->env.xregs[0] = context_id; + } else { + target_cpu->env.regs[0] = context_id; + target_cpu->env.thumb = entry & 1; + } + target_cpu_class->set_pc(target_cpu_state, entry); + + ret = 0; + 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: + cpu->powered_off = true; + cs->halted = 1; + cs->exception_index = EXCP_HLT; + cpu_loop_exit(cs); + /* notreached */ +}