[qemu.git] / target / arm / arm-powerctl.c

/*
 * QEMU support -- ARM Power Control specific functions.
 *
 * Copyright (c) 2016 Jean-Christophe Dubois
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
 * See the COPYING file in the top-level directory.
 *
 */

#include "qemu/osdep.h"
#include "cpu.h"
#include "cpu-qom.h"
#include "internals.h"
#include "arm-powerctl.h"
#include "qemu/log.h"
#include "qemu/main-loop.h"

#ifndef DEBUG_ARM_POWERCTL
#define DEBUG_ARM_POWERCTL 0
#endif

#define DPRINTF(fmt, args...) \
    do { \
        if (DEBUG_ARM_POWERCTL) { \
            fprintf(stderr, "[ARM]%s: " fmt , __func__, ##args); \
        } \
    } while (0)

CPUState *arm_get_cpu_by_id(uint64_t id)
{
    CPUState *cpu;

    DPRINTF("cpu %" PRId64 "\n", id);

    CPU_FOREACH(cpu) {
        ARMCPU *armcpu = ARM_CPU(cpu);

        if (armcpu->mp_affinity == id) {
            return cpu;
        }
    }

    qemu_log_mask(LOG_GUEST_ERROR,
                  "[ARM]%s: Requesting unknown CPU %" PRId64 "\n",
                  __func__, id);

    return NULL;
}

struct CpuOnInfo {
    uint64_t entry;
    uint64_t context_id;
    uint32_t target_el;
    bool target_aa64;
};


static void arm_set_cpu_on_async_work(CPUState *target_cpu_state,
                                      run_on_cpu_data data)
{
    ARMCPU *target_cpu = ARM_CPU(target_cpu_state);
    struct CpuOnInfo *info = (struct CpuOnInfo *) data.host_ptr;

    /* Initialize the cpu we are turning on */
    cpu_reset(target_cpu_state);
    target_cpu_state->halted = 0;

    if (info->target_aa64) {
        if ((info->target_el < 3) && arm_feature(&target_cpu->env,
                                                 ARM_FEATURE_EL3)) {
            /*
             * As target mode is AArch64, we need to set lower
             * exception level (the requested level 2) to AArch64
             */
            target_cpu->env.cp15.scr_el3 |= SCR_RW;
        }

        if ((info->target_el < 2) && arm_feature(&target_cpu->env,
                                                 ARM_FEATURE_EL2)) {
            /*
             * As target mode is AArch64, we need to set lower
             * exception level (the requested level 1) to AArch64
             */
            target_cpu->env.cp15.hcr_el2 |= HCR_RW;
        }

        target_cpu->env.pstate = aarch64_pstate_mode(info->target_el, true);
    } else {
        /* We are requested to boot in AArch32 mode */
        static const uint32_t mode_for_el[] = { 0,
                                                ARM_CPU_MODE_SVC,
                                                ARM_CPU_MODE_HYP,
                                                ARM_CPU_MODE_SVC };

        cpsr_write(&target_cpu->env, mode_for_el[info->target_el], CPSR_M,
                   CPSRWriteRaw);
    }

    if (info->target_el == 3) {
        /* Processor is in secure mode */
        target_cpu->env.cp15.scr_el3 &= ~SCR_NS;
    } else {
        /* Processor is not in secure mode */
        target_cpu->env.cp15.scr_el3 |= SCR_NS;

        /*
         * If QEMU is providing the equivalent of EL3 firmware, then we need
         * to make sure a CPU targeting EL2 comes out of reset with a
         * functional HVC insn.
         */
        if (arm_feature(&target_cpu->env, ARM_FEATURE_EL3)
            && info->target_el == 2) {
            target_cpu->env.cp15.scr_el3 |= SCR_HCE;
        }
    }

    /* We check if the started CPU is now at the correct level */
    assert(info->target_el == arm_current_el(&target_cpu->env));

    if (info->target_aa64) {
        target_cpu->env.xregs[0] = info->context_id;
    } else {
        target_cpu->env.regs[0] = info->context_id;
    }

    /* Start the new CPU at the requested address */
    cpu_set_pc(target_cpu_state, info->entry);

    g_free(info);

    /* Finally set the power status */
    assert(qemu_mutex_iothread_locked());
    target_cpu->power_state = PSCI_ON;
}

int arm_set_cpu_on(uint64_t cpuid, uint64_t entry, uint64_t context_id,
                   uint32_t target_el, bool target_aa64)
{
    CPUState *target_cpu_state;
    ARMCPU *target_cpu;
    struct CpuOnInfo *info;

    assert(qemu_mutex_iothread_locked());

    DPRINTF("cpu %" PRId64 " (EL %d, %s) @ 0x%" PRIx64 " with R0 = 0x%" PRIx64
            "\n", cpuid, target_el, target_aa64 ? "aarch64" : "aarch32", entry,
            context_id);

    /* requested EL level need to be in the 1 to 3 range */
    assert((target_el > 0) && (target_el < 4));

    if (target_aa64 && (entry & 3)) {
        /*
         * if we are booting in AArch64 mode then "entry" needs to be 4 bytes
         * aligned.
         */
        return QEMU_ARM_POWERCTL_INVALID_PARAM;
    }

    /* Retrieve the cpu we are powering up */
    target_cpu_state = arm_get_cpu_by_id(cpuid);
    if (!target_cpu_state) {
        /* The cpu was not found */
        return QEMU_ARM_POWERCTL_INVALID_PARAM;
    }

    target_cpu = ARM_CPU(target_cpu_state);
    if (target_cpu->power_state == PSCI_ON) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "[ARM]%s: CPU %" PRId64 " is already on\n",
                      __func__, cpuid);
        return QEMU_ARM_POWERCTL_ALREADY_ON;
    }

    /*
     * The newly brought CPU is requested to enter the exception level
     * "target_el" and be in the requested mode (AArch64 or AArch32).
     */

    if (((target_el == 3) && !arm_feature(&target_cpu->env, ARM_FEATURE_EL3)) ||
        ((target_el == 2) && !arm_feature(&target_cpu->env, ARM_FEATURE_EL2))) {
        /*
         * The CPU does not support requested level
         */
        return QEMU_ARM_POWERCTL_INVALID_PARAM;
    }

    if (!target_aa64 && arm_feature(&target_cpu->env, ARM_FEATURE_AARCH64)) {
        /*
         * For now we don't support booting an AArch64 CPU in AArch32 mode
         * TODO: We should add this support later
         */
        qemu_log_mask(LOG_UNIMP,
                      "[ARM]%s: Starting AArch64 CPU %" PRId64
                      " in AArch32 mode is not supported yet\n",
                      __func__, cpuid);
        return QEMU_ARM_POWERCTL_INVALID_PARAM;
    }

    /*
     * If another CPU has powered the target on we are in the state
     * ON_PENDING and additional attempts to power on the CPU should
     * fail (see 6.6 Implementation CPU_ON/CPU_OFF races in the PSCI
     * spec)
     */
    if (target_cpu->power_state == PSCI_ON_PENDING) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "[ARM]%s: CPU %" PRId64 " is already powering on\n",
                      __func__, cpuid);
        return QEMU_ARM_POWERCTL_ON_PENDING;
    }

    /* To avoid racing with a CPU we are just kicking off we do the
     * final bit of preparation for the work in the target CPUs
     * context.
     */
    info = g_new(struct CpuOnInfo, 1);
    info->entry = entry;
    info->context_id = context_id;
    info->target_el = target_el;
    info->target_aa64 = target_aa64;

    async_run_on_cpu(target_cpu_state, arm_set_cpu_on_async_work,
                     RUN_ON_CPU_HOST_PTR(info));

    /* We are good to go */
    return QEMU_ARM_POWERCTL_RET_SUCCESS;
}

static void arm_set_cpu_on_and_reset_async_work(CPUState *target_cpu_state,
                                                run_on_cpu_data data)
{
    ARMCPU *target_cpu = ARM_CPU(target_cpu_state);

    /* Initialize the cpu we are turning on */
    cpu_reset(target_cpu_state);
    target_cpu_state->halted = 0;

    /* Finally set the power status */
    assert(qemu_mutex_iothread_locked());
    target_cpu->power_state = PSCI_ON;
}

int arm_set_cpu_on_and_reset(uint64_t cpuid)
{
    CPUState *target_cpu_state;
    ARMCPU *target_cpu;

    assert(qemu_mutex_iothread_locked());

    /* Retrieve the cpu we are powering up */
    target_cpu_state = arm_get_cpu_by_id(cpuid);
    if (!target_cpu_state) {
        /* The cpu was not found */
        return QEMU_ARM_POWERCTL_INVALID_PARAM;
    }

    target_cpu = ARM_CPU(target_cpu_state);
    if (target_cpu->power_state == PSCI_ON) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "[ARM]%s: CPU %" PRId64 " is already on\n",
                      __func__, cpuid);
        return QEMU_ARM_POWERCTL_ALREADY_ON;
    }

    /*
     * If another CPU has powered the target on we are in the state
     * ON_PENDING and additional attempts to power on the CPU should
     * fail (see 6.6 Implementation CPU_ON/CPU_OFF races in the PSCI
     * spec)
     */
    if (target_cpu->power_state == PSCI_ON_PENDING) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "[ARM]%s: CPU %" PRId64 " is already powering on\n",
                      __func__, cpuid);
        return QEMU_ARM_POWERCTL_ON_PENDING;
    }

    async_run_on_cpu(target_cpu_state, arm_set_cpu_on_and_reset_async_work,
                     RUN_ON_CPU_NULL);

    /* We are good to go */
    return QEMU_ARM_POWERCTL_RET_SUCCESS;
}

static void arm_set_cpu_off_async_work(CPUState *target_cpu_state,
                                       run_on_cpu_data data)
{
    ARMCPU *target_cpu = ARM_CPU(target_cpu_state);

    assert(qemu_mutex_iothread_locked());
    target_cpu->power_state = PSCI_OFF;
    target_cpu_state->halted = 1;
    target_cpu_state->exception_index = EXCP_HLT;
}

int arm_set_cpu_off(uint64_t cpuid)
{
    CPUState *target_cpu_state;
    ARMCPU *target_cpu;

    assert(qemu_mutex_iothread_locked());

    DPRINTF("cpu %" PRId64 "\n", cpuid);

    /* change to the cpu we are powering up */
    target_cpu_state = arm_get_cpu_by_id(cpuid);
    if (!target_cpu_state) {
        return QEMU_ARM_POWERCTL_INVALID_PARAM;
    }
    target_cpu = ARM_CPU(target_cpu_state);
    if (target_cpu->power_state == PSCI_OFF) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "[ARM]%s: CPU %" PRId64 " is already off\n",
                      __func__, cpuid);
        return QEMU_ARM_POWERCTL_IS_OFF;
    }

    /* Queue work to run under the target vCPUs context */
    async_run_on_cpu(target_cpu_state, arm_set_cpu_off_async_work,
                     RUN_ON_CPU_NULL);

    return QEMU_ARM_POWERCTL_RET_SUCCESS;
}

static void arm_reset_cpu_async_work(CPUState *target_cpu_state,
                                     run_on_cpu_data data)
{
    /* Reset the cpu */
    cpu_reset(target_cpu_state);
}

int arm_reset_cpu(uint64_t cpuid)
{
    CPUState *target_cpu_state;
    ARMCPU *target_cpu;

    assert(qemu_mutex_iothread_locked());

    DPRINTF("cpu %" PRId64 "\n", cpuid);

    /* change to the cpu we are resetting */
    target_cpu_state = arm_get_cpu_by_id(cpuid);
    if (!target_cpu_state) {
        return QEMU_ARM_POWERCTL_INVALID_PARAM;
    }
    target_cpu = ARM_CPU(target_cpu_state);

    if (target_cpu->power_state == PSCI_OFF) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "[ARM]%s: CPU %" PRId64 " is off\n",
                      __func__, cpuid);
        return QEMU_ARM_POWERCTL_IS_OFF;
    }

    /* Queue work to run under the target vCPUs context */
    async_run_on_cpu(target_cpu_state, arm_reset_cpu_async_work,
                     RUN_ON_CPU_NULL);

    return QEMU_ARM_POWERCTL_RET_SUCCESS;
}
Commit	Line	Data
825482ad JCD	1	/*
	2	* QEMU support -- ARM Power Control specific functions.
	3	*
	4	* Copyright (c) 2016 Jean-Christophe Dubois
	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 "qemu/osdep.h"
a9c94277 MA	12	#include "cpu.h"
a9c94277 MA	13	#include "cpu-qom.h"
825482ad JCD	14	#include "internals.h"
825482ad JCD	15	#include "arm-powerctl.h"
03dd024f	16	#include "qemu/log.h"
062ba099	17	#include "qemu/main-loop.h"
825482ad JCD	18
	19	#ifndef DEBUG_ARM_POWERCTL
	20	#define DEBUG_ARM_POWERCTL 0
	21	#endif
	22
	23	#define DPRINTF(fmt, args...) \
	24	do { \
	25	if (DEBUG_ARM_POWERCTL) { \
	26	fprintf(stderr, "[ARM]%s: " fmt , __func__, ##args); \
	27	} \
	28	} while (0)
	29
	30	CPUState *arm_get_cpu_by_id(uint64_t id)
	31	{
	32	CPUState *cpu;
	33
	34	DPRINTF("cpu %" PRId64 "\n", id);
	35
	36	CPU_FOREACH(cpu) {
	37	ARMCPU *armcpu = ARM_CPU(cpu);
	38
	39	if (armcpu->mp_affinity == id) {
	40	return cpu;
	41	}
	42	}
	43
	44	qemu_log_mask(LOG_GUEST_ERROR,
	45	"[ARM]%s: Requesting unknown CPU %" PRId64 "\n",
	46	__func__, id);
	47
	48	return NULL;
	49	}
	50
062ba099 AB	51	struct CpuOnInfo {
	52	uint64_t entry;
	53	uint64_t context_id;
	54	uint32_t target_el;
	55	bool target_aa64;
	56	};
	57
	58
	59	static void arm_set_cpu_on_async_work(CPUState *target_cpu_state,
	60	run_on_cpu_data data)
	61	{
	62	ARMCPU *target_cpu = ARM_CPU(target_cpu_state);
	63	struct CpuOnInfo info = (struct CpuOnInfo ) data.host_ptr;
	64
	65	/* Initialize the cpu we are turning on */
	66	cpu_reset(target_cpu_state);
	67	target_cpu_state->halted = 0;
	68
	69	if (info->target_aa64) {
	70	if ((info->target_el < 3) && arm_feature(&target_cpu->env,
	71	ARM_FEATURE_EL3)) {
	72	/*
	73	* As target mode is AArch64, we need to set lower
	74	* exception level (the requested level 2) to AArch64
	75	*/
	76	target_cpu->env.cp15.scr_el3 \|= SCR_RW;
	77	}
	78
	79	if ((info->target_el < 2) && arm_feature(&target_cpu->env,
	80	ARM_FEATURE_EL2)) {
	81	/*
	82	* As target mode is AArch64, we need to set lower
	83	* exception level (the requested level 1) to AArch64
	84	*/
	85	target_cpu->env.cp15.hcr_el2 \|= HCR_RW;
	86	}
	87
	88	target_cpu->env.pstate = aarch64_pstate_mode(info->target_el, true);
	89	} else {
	90	/* We are requested to boot in AArch32 mode */
	91	static const uint32_t mode_for_el[] = { 0,
	92	ARM_CPU_MODE_SVC,
	93	ARM_CPU_MODE_HYP,
	94	ARM_CPU_MODE_SVC };
	95
	96	cpsr_write(&target_cpu->env, mode_for_el[info->target_el], CPSR_M,
	97	CPSRWriteRaw);
	98	}
	99
	100	if (info->target_el == 3) {
	101	/* Processor is in secure mode */
	102	target_cpu->env.cp15.scr_el3 &= ~SCR_NS;
	103	} else {
	104	/* Processor is not in secure mode */
	105	target_cpu->env.cp15.scr_el3 \|= SCR_NS;
86278c33 EI	106
	107	/*
	108	* If QEMU is providing the equivalent of EL3 firmware, then we need
	109	* to make sure a CPU targeting EL2 comes out of reset with a
	110	* functional HVC insn.
	111	*/
	112	if (arm_feature(&target_cpu->env, ARM_FEATURE_EL3)
	113	&& info->target_el == 2) {
	114	target_cpu->env.cp15.scr_el3 \|= SCR_HCE;
	115	}
062ba099 AB	116	}
	117
	118	/* We check if the started CPU is now at the correct level */
	119	assert(info->target_el == arm_current_el(&target_cpu->env));
	120
	121	if (info->target_aa64) {
	122	target_cpu->env.xregs[0] = info->context_id;
062ba099 AB	123	} else {
062ba099 AB	124	target_cpu->env.regs[0] = info->context_id;
062ba099 AB	125	}
	126
	127	/* Start the new CPU at the requested address */
	128	cpu_set_pc(target_cpu_state, info->entry);
	129
	130	g_free(info);
	131
	132	/* Finally set the power status */
	133	assert(qemu_mutex_iothread_locked());
	134	target_cpu->power_state = PSCI_ON;
	135	}
	136
825482ad JCD	137	int arm_set_cpu_on(uint64_t cpuid, uint64_t entry, uint64_t context_id,
	138	uint32_t target_el, bool target_aa64)
	139	{
	140	CPUState *target_cpu_state;
	141	ARMCPU *target_cpu;
062ba099 AB	142	struct CpuOnInfo *info;
	143
	144	assert(qemu_mutex_iothread_locked());
825482ad JCD	145
	146	DPRINTF("cpu %" PRId64 " (EL %d, %s) @ 0x%" PRIx64 " with R0 = 0x%" PRIx64
	147	"\n", cpuid, target_el, target_aa64 ? "aarch64" : "aarch32", entry,
	148	context_id);
	149
	150	/* requested EL level need to be in the 1 to 3 range */
	151	assert((target_el > 0) && (target_el < 4));
	152
	153	if (target_aa64 && (entry & 3)) {
	154	/*
	155	* if we are booting in AArch64 mode then "entry" needs to be 4 bytes
	156	* aligned.
	157	*/
	158	return QEMU_ARM_POWERCTL_INVALID_PARAM;
	159	}
	160
	161	/* Retrieve the cpu we are powering up */
	162	target_cpu_state = arm_get_cpu_by_id(cpuid);
	163	if (!target_cpu_state) {
	164	/* The cpu was not found */
	165	return QEMU_ARM_POWERCTL_INVALID_PARAM;
	166	}
	167
	168	target_cpu = ARM_CPU(target_cpu_state);
062ba099	169	if (target_cpu->power_state == PSCI_ON) {
825482ad JCD	170	qemu_log_mask(LOG_GUEST_ERROR,
	171	"[ARM]%s: CPU %" PRId64 " is already on\n",
	172	__func__, cpuid);
	173	return QEMU_ARM_POWERCTL_ALREADY_ON;
	174	}
	175
	176	/*
	177	* The newly brought CPU is requested to enter the exception level
	178	* "target_el" and be in the requested mode (AArch64 or AArch32).
	179	*/
	180
	181	if (((target_el == 3) && !arm_feature(&target_cpu->env, ARM_FEATURE_EL3)) \|\|
	182	((target_el == 2) && !arm_feature(&target_cpu->env, ARM_FEATURE_EL2))) {
	183	/*
	184	* The CPU does not support requested level
	185	*/
	186	return QEMU_ARM_POWERCTL_INVALID_PARAM;
	187	}
	188
	189	if (!target_aa64 && arm_feature(&target_cpu->env, ARM_FEATURE_AARCH64)) {
	190	/*
	191	* For now we don't support booting an AArch64 CPU in AArch32 mode
	192	* TODO: We should add this support later
	193	*/
	194	qemu_log_mask(LOG_UNIMP,
	195	"[ARM]%s: Starting AArch64 CPU %" PRId64
	196	" in AArch32 mode is not supported yet\n",
	197	__func__, cpuid);
	198	return QEMU_ARM_POWERCTL_INVALID_PARAM;
	199	}
	200
062ba099 AB	201	/*
	202	* If another CPU has powered the target on we are in the state
	203	* ON_PENDING and additional attempts to power on the CPU should
	204	* fail (see 6.6 Implementation CPU_ON/CPU_OFF races in the PSCI
	205	* spec)
	206	*/
	207	if (target_cpu->power_state == PSCI_ON_PENDING) {
	208	qemu_log_mask(LOG_GUEST_ERROR,
	209	"[ARM]%s: CPU %" PRId64 " is already powering on\n",
	210	__func__, cpuid);
	211	return QEMU_ARM_POWERCTL_ON_PENDING;
825482ad JCD	212	}
825482ad JCD	213
062ba099 AB	214	/* To avoid racing with a CPU we are just kicking off we do the
	215	* final bit of preparation for the work in the target CPUs
	216	* context.
	217	*/
	218	info = g_new(struct CpuOnInfo, 1);
	219	info->entry = entry;
	220	info->context_id = context_id;
	221	info->target_el = target_el;
	222	info->target_aa64 = target_aa64;
825482ad	223
062ba099 AB	224	async_run_on_cpu(target_cpu_state, arm_set_cpu_on_async_work,
062ba099 AB	225	RUN_ON_CPU_HOST_PTR(info));
548ebcaf	226
825482ad JCD	227	/* We are good to go */
	228	return QEMU_ARM_POWERCTL_RET_SUCCESS;
	229	}
	230
ea824b97 PM	231	static void arm_set_cpu_on_and_reset_async_work(CPUState *target_cpu_state,
	232	run_on_cpu_data data)
	233	{
	234	ARMCPU *target_cpu = ARM_CPU(target_cpu_state);
	235
	236	/* Initialize the cpu we are turning on */
	237	cpu_reset(target_cpu_state);
	238	target_cpu_state->halted = 0;
	239
	240	/* Finally set the power status */
	241	assert(qemu_mutex_iothread_locked());
	242	target_cpu->power_state = PSCI_ON;
	243	}
	244
	245	int arm_set_cpu_on_and_reset(uint64_t cpuid)
	246	{
	247	CPUState *target_cpu_state;
	248	ARMCPU *target_cpu;
	249
	250	assert(qemu_mutex_iothread_locked());
	251
	252	/* Retrieve the cpu we are powering up */
	253	target_cpu_state = arm_get_cpu_by_id(cpuid);
	254	if (!target_cpu_state) {
	255	/* The cpu was not found */
	256	return QEMU_ARM_POWERCTL_INVALID_PARAM;
	257	}
	258
	259	target_cpu = ARM_CPU(target_cpu_state);
	260	if (target_cpu->power_state == PSCI_ON) {
	261	qemu_log_mask(LOG_GUEST_ERROR,
	262	"[ARM]%s: CPU %" PRId64 " is already on\n",
	263	__func__, cpuid);
	264	return QEMU_ARM_POWERCTL_ALREADY_ON;
	265	}
	266
	267	/*
	268	* If another CPU has powered the target on we are in the state
	269	* ON_PENDING and additional attempts to power on the CPU should
	270	* fail (see 6.6 Implementation CPU_ON/CPU_OFF races in the PSCI
	271	* spec)
	272	*/
	273	if (target_cpu->power_state == PSCI_ON_PENDING) {
	274	qemu_log_mask(LOG_GUEST_ERROR,
	275	"[ARM]%s: CPU %" PRId64 " is already powering on\n",
	276	__func__, cpuid);
	277	return QEMU_ARM_POWERCTL_ON_PENDING;
	278	}
	279
	280	async_run_on_cpu(target_cpu_state, arm_set_cpu_on_and_reset_async_work,
	281	RUN_ON_CPU_NULL);
	282
	283	/* We are good to go */
	284	return QEMU_ARM_POWERCTL_RET_SUCCESS;
	285	}
	286
062ba099 AB	287	static void arm_set_cpu_off_async_work(CPUState *target_cpu_state,
	288	run_on_cpu_data data)
	289	{
	290	ARMCPU *target_cpu = ARM_CPU(target_cpu_state);
	291
	292	assert(qemu_mutex_iothread_locked());
	293	target_cpu->power_state = PSCI_OFF;
	294	target_cpu_state->halted = 1;
	295	target_cpu_state->exception_index = EXCP_HLT;
	296	}
	297
825482ad JCD	298	int arm_set_cpu_off(uint64_t cpuid)
	299	{
	300	CPUState *target_cpu_state;
	301	ARMCPU *target_cpu;
	302
062ba099 AB	303	assert(qemu_mutex_iothread_locked());
062ba099 AB	304
825482ad JCD	305	DPRINTF("cpu %" PRId64 "\n", cpuid);
	306
	307	/* change to the cpu we are powering up */
	308	target_cpu_state = arm_get_cpu_by_id(cpuid);
	309	if (!target_cpu_state) {
	310	return QEMU_ARM_POWERCTL_INVALID_PARAM;
	311	}
	312	target_cpu = ARM_CPU(target_cpu_state);
062ba099	313	if (target_cpu->power_state == PSCI_OFF) {
825482ad JCD	314	qemu_log_mask(LOG_GUEST_ERROR,
	315	"[ARM]%s: CPU %" PRId64 " is already off\n",
	316	__func__, cpuid);
	317	return QEMU_ARM_POWERCTL_IS_OFF;
	318	}
	319
062ba099 AB	320	/* Queue work to run under the target vCPUs context */
	321	async_run_on_cpu(target_cpu_state, arm_set_cpu_off_async_work,
	322	RUN_ON_CPU_NULL);
825482ad JCD	323
	324	return QEMU_ARM_POWERCTL_RET_SUCCESS;
	325	}
	326
062ba099 AB	327	static void arm_reset_cpu_async_work(CPUState *target_cpu_state,
	328	run_on_cpu_data data)
	329	{
	330	/* Reset the cpu */
	331	cpu_reset(target_cpu_state);
	332	}
	333
825482ad JCD	334	int arm_reset_cpu(uint64_t cpuid)
	335	{
	336	CPUState *target_cpu_state;
	337	ARMCPU *target_cpu;
	338
062ba099 AB	339	assert(qemu_mutex_iothread_locked());
062ba099 AB	340
825482ad JCD	341	DPRINTF("cpu %" PRId64 "\n", cpuid);
	342
	343	/* change to the cpu we are resetting */
	344	target_cpu_state = arm_get_cpu_by_id(cpuid);
	345	if (!target_cpu_state) {
	346	return QEMU_ARM_POWERCTL_INVALID_PARAM;
	347	}
	348	target_cpu = ARM_CPU(target_cpu_state);
062ba099 AB	349
062ba099 AB	350	if (target_cpu->power_state == PSCI_OFF) {
825482ad JCD	351	qemu_log_mask(LOG_GUEST_ERROR,
	352	"[ARM]%s: CPU %" PRId64 " is off\n",
	353	__func__, cpuid);
	354	return QEMU_ARM_POWERCTL_IS_OFF;
	355	}
	356
062ba099 AB	357	/* Queue work to run under the target vCPUs context */
	358	async_run_on_cpu(target_cpu_state, arm_reset_cpu_async_work,
	359	RUN_ON_CPU_NULL);
825482ad JCD	360
	361	return QEMU_ARM_POWERCTL_RET_SUCCESS;
	362	}