[mirror_ubuntu-artful-kernel.git] / virt / kvm / arm / psci.c

/*
 * Copyright (C) 2012 - ARM Ltd
 * Author: Marc Zyngier <marc.zyngier@arm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * 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 <linux/preempt.h>
#include <linux/kvm_host.h>
#include <linux/wait.h>

#include <asm/cputype.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_host.h>

#include <kvm/arm_psci.h>

/*
 * This is an implementation of the Power State Coordination Interface
 * as described in ARM document number ARM DEN 0022A.
 */

#define AFFINITY_MASK(level)	~((0x1UL << ((level) * MPIDR_LEVEL_BITS)) - 1)

static u32 smccc_get_function(struct kvm_vcpu *vcpu)
{
	return vcpu_get_reg(vcpu, 0);
}

static unsigned long smccc_get_arg1(struct kvm_vcpu *vcpu)
{
	return vcpu_get_reg(vcpu, 1);
}

static unsigned long smccc_get_arg2(struct kvm_vcpu *vcpu)
{
	return vcpu_get_reg(vcpu, 2);
}

static unsigned long smccc_get_arg3(struct kvm_vcpu *vcpu)
{
	return vcpu_get_reg(vcpu, 3);
}

static void smccc_set_retval(struct kvm_vcpu *vcpu,
			     unsigned long a0,
			     unsigned long a1,
			     unsigned long a2,
			     unsigned long a3)
{
	vcpu_set_reg(vcpu, 0, a0);
	vcpu_set_reg(vcpu, 1, a1);
	vcpu_set_reg(vcpu, 2, a2);
	vcpu_set_reg(vcpu, 3, a3);
}

static unsigned long psci_affinity_mask(unsigned long affinity_level)
{
	if (affinity_level <= 3)
		return MPIDR_HWID_BITMASK & AFFINITY_MASK(affinity_level);

	return 0;
}

static unsigned long kvm_psci_vcpu_suspend(struct kvm_vcpu *vcpu)
{
	/*
	 * NOTE: For simplicity, we make VCPU suspend emulation to be
	 * same-as WFI (Wait-for-interrupt) emulation.
	 *
	 * This means for KVM the wakeup events are interrupts and
	 * this is consistent with intended use of StateID as described
	 * in section 5.4.1 of PSCI v0.2 specification (ARM DEN 0022A).
	 *
	 * Further, we also treat power-down request to be same as
	 * stand-by request as-per section 5.4.2 clause 3 of PSCI v0.2
	 * specification (ARM DEN 0022A). This means all suspend states
	 * for KVM will preserve the register state.
	 */
	kvm_vcpu_block(vcpu);
	kvm_clear_request(KVM_REQ_UNHALT, vcpu);

	return PSCI_RET_SUCCESS;
}

static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu)
{
	vcpu->arch.power_off = true;
	kvm_make_request(KVM_REQ_SLEEP, vcpu);
	kvm_vcpu_kick(vcpu);
}

static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
{
	struct kvm *kvm = source_vcpu->kvm;
	struct kvm_vcpu *vcpu = NULL;
	struct swait_queue_head *wq;
	unsigned long cpu_id;
	unsigned long context_id;
	phys_addr_t target_pc;

	cpu_id = smccc_get_arg1(source_vcpu) & MPIDR_HWID_BITMASK;
	if (vcpu_mode_is_32bit(source_vcpu))
		cpu_id &= ~((u32) 0);

	vcpu = kvm_mpidr_to_vcpu(kvm, cpu_id);

	/*
	 * Make sure the caller requested a valid CPU and that the CPU is
	 * turned off.
	 */
	if (!vcpu)
		return PSCI_RET_INVALID_PARAMS;
	if (!vcpu->arch.power_off) {
		if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1)
			return PSCI_RET_ALREADY_ON;
		else
			return PSCI_RET_INVALID_PARAMS;
	}

	target_pc = smccc_get_arg2(source_vcpu);
	context_id = smccc_get_arg3(source_vcpu);

	kvm_reset_vcpu(vcpu);

	/* Gracefully handle Thumb2 entry point */
	if (vcpu_mode_is_32bit(vcpu) && (target_pc & 1)) {
		target_pc &= ~((phys_addr_t) 1);
		vcpu_set_thumb(vcpu);
	}

	/* Propagate caller endianness */
	if (kvm_vcpu_is_be(source_vcpu))
		kvm_vcpu_set_be(vcpu);

	*vcpu_pc(vcpu) = target_pc;
	/*
	 * NOTE: We always update r0 (or x0) because for PSCI v0.1
	 * the general puspose registers are undefined upon CPU_ON.
	 */
	smccc_set_retval(vcpu, context_id, 0, 0, 0);
	vcpu->arch.power_off = false;
	smp_mb();		/* Make sure the above is visible */

	wq = kvm_arch_vcpu_wq(vcpu);
	swake_up(wq);

	return PSCI_RET_SUCCESS;
}

static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu)
{
	int i, matching_cpus = 0;
	unsigned long mpidr;
	unsigned long target_affinity;
	unsigned long target_affinity_mask;
	unsigned long lowest_affinity_level;
	struct kvm *kvm = vcpu->kvm;
	struct kvm_vcpu *tmp;

	target_affinity = smccc_get_arg1(vcpu);
	lowest_affinity_level = smccc_get_arg2(vcpu);

	/* Determine target affinity mask */
	target_affinity_mask = psci_affinity_mask(lowest_affinity_level);
	if (!target_affinity_mask)
		return PSCI_RET_INVALID_PARAMS;

	/* Ignore other bits of target affinity */
	target_affinity &= target_affinity_mask;

	/*
	 * If one or more VCPU matching target affinity are running
	 * then ON else OFF
	 */
	kvm_for_each_vcpu(i, tmp, kvm) {
		mpidr = kvm_vcpu_get_mpidr_aff(tmp);
		if ((mpidr & target_affinity_mask) == target_affinity) {
			matching_cpus++;
			if (!tmp->arch.power_off)
				return PSCI_0_2_AFFINITY_LEVEL_ON;
		}
	}

	if (!matching_cpus)
		return PSCI_RET_INVALID_PARAMS;

	return PSCI_0_2_AFFINITY_LEVEL_OFF;
}

static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type)
{
	int i;
	struct kvm_vcpu *tmp;

	/*
	 * The KVM ABI specifies that a system event exit may call KVM_RUN
	 * again and may perform shutdown/reboot at a later time that when the
	 * actual request is made.  Since we are implementing PSCI and a
	 * caller of PSCI reboot and shutdown expects that the system shuts
	 * down or reboots immediately, let's make sure that VCPUs are not run
	 * after this call is handled and before the VCPUs have been
	 * re-initialized.
	 */
	kvm_for_each_vcpu(i, tmp, vcpu->kvm)
		tmp->arch.power_off = true;
	kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_SLEEP);

	memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
	vcpu->run->system_event.type = type;
	vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
}

static void kvm_psci_system_off(struct kvm_vcpu *vcpu)
{
	kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_SHUTDOWN);
}

static void kvm_psci_system_reset(struct kvm_vcpu *vcpu)
{
	kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET);
}

int kvm_psci_version(struct kvm_vcpu *vcpu)
{
	if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
		return KVM_ARM_PSCI_LATEST;

	return KVM_ARM_PSCI_0_1;
}

static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
{
	struct kvm *kvm = vcpu->kvm;
	u32 psci_fn = smccc_get_function(vcpu);
	unsigned long val;
	int ret = 1;

	switch (psci_fn) {
	case PSCI_0_2_FN_PSCI_VERSION:
		/*
		 * Bits[31:16] = Major Version = 0
		 * Bits[15:0] = Minor Version = 2
		 */
		val = KVM_ARM_PSCI_0_2;
		break;
	case PSCI_0_2_FN_CPU_SUSPEND:
	case PSCI_0_2_FN64_CPU_SUSPEND:
		val = kvm_psci_vcpu_suspend(vcpu);
		break;
	case PSCI_0_2_FN_CPU_OFF:
		kvm_psci_vcpu_off(vcpu);
		val = PSCI_RET_SUCCESS;
		break;
	case PSCI_0_2_FN_CPU_ON:
	case PSCI_0_2_FN64_CPU_ON:
		mutex_lock(&kvm->lock);
		val = kvm_psci_vcpu_on(vcpu);
		mutex_unlock(&kvm->lock);
		break;
	case PSCI_0_2_FN_AFFINITY_INFO:
	case PSCI_0_2_FN64_AFFINITY_INFO:
		val = kvm_psci_vcpu_affinity_info(vcpu);
		break;
	case PSCI_0_2_FN_MIGRATE_INFO_TYPE:
		/*
		 * Trusted OS is MP hence does not require migration
	         * or
		 * Trusted OS is not present
		 */
		val = PSCI_0_2_TOS_MP;
		break;
	case PSCI_0_2_FN_SYSTEM_OFF:
		kvm_psci_system_off(vcpu);
		/*
		 * We should'nt be going back to guest VCPU after
		 * receiving SYSTEM_OFF request.
		 *
		 * If user space accidently/deliberately resumes
		 * guest VCPU after SYSTEM_OFF request then guest
		 * VCPU should see internal failure from PSCI return
		 * value. To achieve this, we preload r0 (or x0) with
		 * PSCI return value INTERNAL_FAILURE.
		 */
		val = PSCI_RET_INTERNAL_FAILURE;
		ret = 0;
		break;
	case PSCI_0_2_FN_SYSTEM_RESET:
		kvm_psci_system_reset(vcpu);
		/*
		 * Same reason as SYSTEM_OFF for preloading r0 (or x0)
		 * with PSCI return value INTERNAL_FAILURE.
		 */
		val = PSCI_RET_INTERNAL_FAILURE;
		ret = 0;
		break;
	default:
		val = PSCI_RET_NOT_SUPPORTED;
		break;
	}

	smccc_set_retval(vcpu, val, 0, 0, 0);
	return ret;
}

static int kvm_psci_1_0_call(struct kvm_vcpu *vcpu)
{
	u32 psci_fn = smccc_get_function(vcpu);
	u32 feature;
	unsigned long val;
	int ret = 1;

	switch(psci_fn) {
	case PSCI_0_2_FN_PSCI_VERSION:
		val = KVM_ARM_PSCI_1_0;
		break;
	case PSCI_1_0_FN_PSCI_FEATURES:
		feature = smccc_get_arg1(vcpu);
		switch(feature) {
		case PSCI_0_2_FN_PSCI_VERSION:
		case PSCI_0_2_FN_CPU_SUSPEND:
		case PSCI_0_2_FN64_CPU_SUSPEND:
		case PSCI_0_2_FN_CPU_OFF:
		case PSCI_0_2_FN_CPU_ON:
		case PSCI_0_2_FN64_CPU_ON:
		case PSCI_0_2_FN_AFFINITY_INFO:
		case PSCI_0_2_FN64_AFFINITY_INFO:
		case PSCI_0_2_FN_MIGRATE_INFO_TYPE:
		case PSCI_0_2_FN_SYSTEM_OFF:
		case PSCI_0_2_FN_SYSTEM_RESET:
		case PSCI_1_0_FN_PSCI_FEATURES:
			val = 0;
			break;
		default:
			val = PSCI_RET_NOT_SUPPORTED;
			break;
		}
		break;
	default:
		return kvm_psci_0_2_call(vcpu);
	}

	smccc_set_retval(vcpu, val, 0, 0, 0);
	return ret;
}

static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu)
{
	struct kvm *kvm = vcpu->kvm;
	u32 psci_fn = smccc_get_function(vcpu);
	unsigned long val;

	switch (psci_fn) {
	case KVM_PSCI_FN_CPU_OFF:
		kvm_psci_vcpu_off(vcpu);
		val = PSCI_RET_SUCCESS;
		break;
	case KVM_PSCI_FN_CPU_ON:
		mutex_lock(&kvm->lock);
		val = kvm_psci_vcpu_on(vcpu);
		mutex_unlock(&kvm->lock);
		break;
	default:
		val = PSCI_RET_NOT_SUPPORTED;
		break;
	}

	smccc_set_retval(vcpu, val, 0, 0, 0);
	return 1;
}

/**
 * kvm_psci_call - handle PSCI call if r0 value is in range
 * @vcpu: Pointer to the VCPU struct
 *
 * Handle PSCI calls from guests through traps from HVC instructions.
 * The calling convention is similar to SMC calls to the secure world
 * where the function number is placed in r0.
 *
 * This function returns: > 0 (success), 0 (success but exit to user
 * space), and < 0 (errors)
 *
 * Errors:
 * -EINVAL: Unrecognized PSCI function
 */
int kvm_psci_call(struct kvm_vcpu *vcpu)
{
	switch (kvm_psci_version(vcpu)) {
	case KVM_ARM_PSCI_1_0:
		return kvm_psci_1_0_call(vcpu);
	case KVM_ARM_PSCI_0_2:
		return kvm_psci_0_2_call(vcpu);
	case KVM_ARM_PSCI_0_1:
		return kvm_psci_0_1_call(vcpu);
	default:
		return -EINVAL;
	};
}
Commit	Line	Data
aa024c2f MZ	1	/*
	2	* Copyright (C) 2012 - ARM Ltd
	3	* Author: Marc Zyngier <marc.zyngier@arm.com>
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License version 2 as
	7	* published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program. If not, see <http://www.gnu.org/licenses/>.
	16	*/
	17
cf5d3188	18	#include <linux/preempt.h>
aa024c2f MZ	19	#include <linux/kvm_host.h>
	20	#include <linux/wait.h>
	21
79c64880	22	#include <asm/cputype.h>
aa024c2f	23	#include <asm/kvm_emulate.h>
4429fc64	24	#include <asm/kvm_host.h>
aa024c2f	25
51c1296c MZ	26	#include <kvm/arm_psci.h>
51c1296c MZ	27
aa024c2f MZ	28	/*
	29	* This is an implementation of the Power State Coordination Interface
	30	* as described in ARM document number ARM DEN 0022A.
	31	*/
	32
e6bc13c8 AP	33	#define AFFINITY_MASK(level) ~((0x1UL << ((level) * MPIDR_LEVEL_BITS)) - 1)
e6bc13c8 AP	34
153dc8be MZ	35	static u32 smccc_get_function(struct kvm_vcpu *vcpu)
	36	{
	37	return vcpu_get_reg(vcpu, 0);
	38	}
	39
	40	static unsigned long smccc_get_arg1(struct kvm_vcpu *vcpu)
	41	{
	42	return vcpu_get_reg(vcpu, 1);
	43	}
	44
	45	static unsigned long smccc_get_arg2(struct kvm_vcpu *vcpu)
	46	{
	47	return vcpu_get_reg(vcpu, 2);
	48	}
	49
	50	static unsigned long smccc_get_arg3(struct kvm_vcpu *vcpu)
	51	{
	52	return vcpu_get_reg(vcpu, 3);
	53	}
	54
	55	static void smccc_set_retval(struct kvm_vcpu *vcpu,
	56	unsigned long a0,
	57	unsigned long a1,
	58	unsigned long a2,
	59	unsigned long a3)
	60	{
	61	vcpu_set_reg(vcpu, 0, a0);
	62	vcpu_set_reg(vcpu, 1, a1);
	63	vcpu_set_reg(vcpu, 2, a2);
	64	vcpu_set_reg(vcpu, 3, a3);
	65	}
	66
e6bc13c8 AP	67	static unsigned long psci_affinity_mask(unsigned long affinity_level)
	68	{
	69	if (affinity_level <= 3)
	70	return MPIDR_HWID_BITMASK & AFFINITY_MASK(affinity_level);
	71
	72	return 0;
	73	}
	74
b376d02b AP	75	static unsigned long kvm_psci_vcpu_suspend(struct kvm_vcpu *vcpu)
	76	{
	77	/*
	78	* NOTE: For simplicity, we make VCPU suspend emulation to be
	79	* same-as WFI (Wait-for-interrupt) emulation.
	80	*
	81	* This means for KVM the wakeup events are interrupts and
	82	* this is consistent with intended use of StateID as described
	83	* in section 5.4.1 of PSCI v0.2 specification (ARM DEN 0022A).
	84	*
	85	* Further, we also treat power-down request to be same as
	86	* stand-by request as-per section 5.4.2 clause 3 of PSCI v0.2
	87	* specification (ARM DEN 0022A). This means all suspend states
	88	* for KVM will preserve the register state.
	89	*/
	90	kvm_vcpu_block(vcpu);
6a6d73be	91	kvm_clear_request(KVM_REQ_UNHALT, vcpu);
b376d02b AP	92
	93	return PSCI_RET_SUCCESS;
	94	}
	95
aa024c2f MZ	96	static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu)
aa024c2f MZ	97	{
3781528e	98	vcpu->arch.power_off = true;
7b244e2b	99	kvm_make_request(KVM_REQ_SLEEP, vcpu);
424c989b	100	kvm_vcpu_kick(vcpu);
aa024c2f MZ	101	}
	102
	103	static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
	104	{
	105	struct kvm *kvm = source_vcpu->kvm;
4429fc64	106	struct kvm_vcpu *vcpu = NULL;
8577370f	107	struct swait_queue_head *wq;
aa024c2f	108	unsigned long cpu_id;
aa8aeefe	109	unsigned long context_id;
aa024c2f MZ	110	phys_addr_t target_pc;
aa024c2f MZ	111
153dc8be	112	cpu_id = smccc_get_arg1(source_vcpu) & MPIDR_HWID_BITMASK;
aa024c2f MZ	113	if (vcpu_mode_is_32bit(source_vcpu))
	114	cpu_id &= ~((u32) 0);
	115
4429fc64	116	vcpu = kvm_mpidr_to_vcpu(kvm, cpu_id);
79c64880	117
478a8237 CD	118	/*
	119	* Make sure the caller requested a valid CPU and that the CPU is
	120	* turned off.
	121	*/
aa8aeefe	122	if (!vcpu)
7d0f84aa	123	return PSCI_RET_INVALID_PARAMS;
3781528e	124	if (!vcpu->arch.power_off) {
aa8aeefe AP	125	if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1)
	126	return PSCI_RET_ALREADY_ON;
	127	else
	128	return PSCI_RET_INVALID_PARAMS;
	129	}
aa024c2f	130
153dc8be MZ	131	target_pc = smccc_get_arg2(source_vcpu);
153dc8be MZ	132	context_id = smccc_get_arg3(source_vcpu);
aa024c2f	133
aa024c2f MZ	134	kvm_reset_vcpu(vcpu);
	135
	136	/* Gracefully handle Thumb2 entry point */
	137	if (vcpu_mode_is_32bit(vcpu) && (target_pc & 1)) {
	138	target_pc &= ~((phys_addr_t) 1);
	139	vcpu_set_thumb(vcpu);
	140	}
	141
ce94fe93 MZ	142	/* Propagate caller endianness */
	143	if (kvm_vcpu_is_be(source_vcpu))
	144	kvm_vcpu_set_be(vcpu);
	145
aa024c2f	146	*vcpu_pc(vcpu) = target_pc;
aa8aeefe AP	147	/*
	148	* NOTE: We always update r0 (or x0) because for PSCI v0.1
	149	* the general puspose registers are undefined upon CPU_ON.
	150	*/
153dc8be	151	smccc_set_retval(vcpu, context_id, 0, 0, 0);
3781528e	152	vcpu->arch.power_off = false;
aa024c2f MZ	153	smp_mb(); /* Make sure the above is visible */
aa024c2f MZ	154
478a8237	155	wq = kvm_arch_vcpu_wq(vcpu);
8577370f	156	swake_up(wq);
aa024c2f	157
7d0f84aa	158	return PSCI_RET_SUCCESS;
aa024c2f MZ	159	}
aa024c2f MZ	160
e6bc13c8 AP	161	static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu)
e6bc13c8 AP	162	{
0c067292	163	int i, matching_cpus = 0;
e6bc13c8 AP	164	unsigned long mpidr;
	165	unsigned long target_affinity;
	166	unsigned long target_affinity_mask;
	167	unsigned long lowest_affinity_level;
	168	struct kvm *kvm = vcpu->kvm;
	169	struct kvm_vcpu *tmp;
	170
153dc8be MZ	171	target_affinity = smccc_get_arg1(vcpu);
153dc8be MZ	172	lowest_affinity_level = smccc_get_arg2(vcpu);
e6bc13c8 AP	173
	174	/* Determine target affinity mask */
	175	target_affinity_mask = psci_affinity_mask(lowest_affinity_level);
	176	if (!target_affinity_mask)
	177	return PSCI_RET_INVALID_PARAMS;
	178
	179	/* Ignore other bits of target affinity */
	180	target_affinity &= target_affinity_mask;
	181
	182	/*
	183	* If one or more VCPU matching target affinity are running
	184	* then ON else OFF
	185	*/
	186	kvm_for_each_vcpu(i, tmp, kvm) {
4429fc64	187	mpidr = kvm_vcpu_get_mpidr_aff(tmp);
0c067292 AS	188	if ((mpidr & target_affinity_mask) == target_affinity) {
0c067292 AS	189	matching_cpus++;
3781528e	190	if (!tmp->arch.power_off)
0c067292	191	return PSCI_0_2_AFFINITY_LEVEL_ON;
e6bc13c8 AP	192	}
	193	}
	194
0c067292 AS	195	if (!matching_cpus)
	196	return PSCI_RET_INVALID_PARAMS;
	197
e6bc13c8 AP	198	return PSCI_0_2_AFFINITY_LEVEL_OFF;
	199	}
	200
4b123826 AP	201	static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type)
4b123826 AP	202	{
cf5d3188 CD	203	int i;
	204	struct kvm_vcpu *tmp;
	205
	206	/*
	207	* The KVM ABI specifies that a system event exit may call KVM_RUN
	208	* again and may perform shutdown/reboot at a later time that when the
	209	* actual request is made. Since we are implementing PSCI and a
	210	* caller of PSCI reboot and shutdown expects that the system shuts
	211	* down or reboots immediately, let's make sure that VCPUs are not run
	212	* after this call is handled and before the VCPUs have been
	213	* re-initialized.
	214	*/
cc9b43f9	215	kvm_for_each_vcpu(i, tmp, vcpu->kvm)
3781528e	216	tmp->arch.power_off = true;
7b244e2b	217	kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_SLEEP);
cf5d3188	218
4b123826 AP	219	memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
	220	vcpu->run->system_event.type = type;
	221	vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
	222	}
	223
	224	static void kvm_psci_system_off(struct kvm_vcpu *vcpu)
	225	{
	226	kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_SHUTDOWN);
	227	}
	228
	229	static void kvm_psci_system_reset(struct kvm_vcpu *vcpu)
	230	{
	231	kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET);
	232	}
	233
7d0f84aa AP	234	int kvm_psci_version(struct kvm_vcpu *vcpu)
	235	{
	236	if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
6a2b29fa	237	return KVM_ARM_PSCI_LATEST;
7d0f84aa AP	238
	239	return KVM_ARM_PSCI_0_1;
	240	}
	241
e8e7fcc5	242	static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
7d0f84aa	243	{
6c7a5dce	244	struct kvm *kvm = vcpu->kvm;
153dc8be	245	u32 psci_fn = smccc_get_function(vcpu);
7d0f84aa	246	unsigned long val;
6c7a5dce	247	int ret = 1;
7d0f84aa AP	248
	249	switch (psci_fn) {
	250	case PSCI_0_2_FN_PSCI_VERSION:
	251	/*
	252	* Bits[31:16] = Major Version = 0
	253	* Bits[15:0] = Minor Version = 2
	254	*/
7b40027a	255	val = KVM_ARM_PSCI_0_2;
7d0f84aa	256	break;
b376d02b AP	257	case PSCI_0_2_FN_CPU_SUSPEND:
	258	case PSCI_0_2_FN64_CPU_SUSPEND:
	259	val = kvm_psci_vcpu_suspend(vcpu);
	260	break;
7d0f84aa AP	261	case PSCI_0_2_FN_CPU_OFF:
	262	kvm_psci_vcpu_off(vcpu);
	263	val = PSCI_RET_SUCCESS;
	264	break;
	265	case PSCI_0_2_FN_CPU_ON:
	266	case PSCI_0_2_FN64_CPU_ON:
6c7a5dce	267	mutex_lock(&kvm->lock);
7d0f84aa	268	val = kvm_psci_vcpu_on(vcpu);
6c7a5dce	269	mutex_unlock(&kvm->lock);
7d0f84aa	270	break;
e6bc13c8 AP	271	case PSCI_0_2_FN_AFFINITY_INFO:
	272	case PSCI_0_2_FN64_AFFINITY_INFO:
	273	val = kvm_psci_vcpu_affinity_info(vcpu);
	274	break;
bab0b430 AP	275	case PSCI_0_2_FN_MIGRATE_INFO_TYPE:
	276	/*
	277	* Trusted OS is MP hence does not require migration
	278	* or
	279	* Trusted OS is not present
	280	*/
	281	val = PSCI_0_2_TOS_MP;
	282	break;
4b123826 AP	283	case PSCI_0_2_FN_SYSTEM_OFF:
	284	kvm_psci_system_off(vcpu);
	285	/*
	286	* We should'nt be going back to guest VCPU after
	287	* receiving SYSTEM_OFF request.
	288	*
	289	* If user space accidently/deliberately resumes
	290	* guest VCPU after SYSTEM_OFF request then guest
	291	* VCPU should see internal failure from PSCI return
	292	* value. To achieve this, we preload r0 (or x0) with
	293	* PSCI return value INTERNAL_FAILURE.
	294	*/
	295	val = PSCI_RET_INTERNAL_FAILURE;
	296	ret = 0;
	297	break;
	298	case PSCI_0_2_FN_SYSTEM_RESET:
	299	kvm_psci_system_reset(vcpu);
	300	/*
	301	* Same reason as SYSTEM_OFF for preloading r0 (or x0)
	302	* with PSCI return value INTERNAL_FAILURE.
	303	*/
	304	val = PSCI_RET_INTERNAL_FAILURE;
	305	ret = 0;
	306	break;
7d0f84aa	307	default:
e2d99736 LP	308	val = PSCI_RET_NOT_SUPPORTED;
e2d99736 LP	309	break;
7d0f84aa AP	310	}
7d0f84aa AP	311
153dc8be	312	smccc_set_retval(vcpu, val, 0, 0, 0);
4b123826	313	return ret;
7d0f84aa AP	314	}
7d0f84aa AP	315
6a2b29fa MZ	316	static int kvm_psci_1_0_call(struct kvm_vcpu *vcpu)
	317	{
	318	u32 psci_fn = smccc_get_function(vcpu);
	319	u32 feature;
	320	unsigned long val;
	321	int ret = 1;
	322
	323	switch(psci_fn) {
	324	case PSCI_0_2_FN_PSCI_VERSION:
	325	val = KVM_ARM_PSCI_1_0;
	326	break;
	327	case PSCI_1_0_FN_PSCI_FEATURES:
	328	feature = smccc_get_arg1(vcpu);
	329	switch(feature) {
	330	case PSCI_0_2_FN_PSCI_VERSION:
	331	case PSCI_0_2_FN_CPU_SUSPEND:
	332	case PSCI_0_2_FN64_CPU_SUSPEND:
	333	case PSCI_0_2_FN_CPU_OFF:
	334	case PSCI_0_2_FN_CPU_ON:
	335	case PSCI_0_2_FN64_CPU_ON:
	336	case PSCI_0_2_FN_AFFINITY_INFO:
	337	case PSCI_0_2_FN64_AFFINITY_INFO:
	338	case PSCI_0_2_FN_MIGRATE_INFO_TYPE:
	339	case PSCI_0_2_FN_SYSTEM_OFF:
	340	case PSCI_0_2_FN_SYSTEM_RESET:
	341	case PSCI_1_0_FN_PSCI_FEATURES:
	342	val = 0;
	343	break;
	344	default:
	345	val = PSCI_RET_NOT_SUPPORTED;
	346	break;
	347	}
	348	break;
	349	default:
	350	return kvm_psci_0_2_call(vcpu);
	351	}
	352
	353	smccc_set_retval(vcpu, val, 0, 0, 0);
	354	return ret;
	355	}
	356
e8e7fcc5	357	static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu)
aa024c2f	358	{
6c7a5dce	359	struct kvm *kvm = vcpu->kvm;
153dc8be	360	u32 psci_fn = smccc_get_function(vcpu);
aa024c2f MZ	361	unsigned long val;
	362
	363	switch (psci_fn) {
	364	case KVM_PSCI_FN_CPU_OFF:
	365	kvm_psci_vcpu_off(vcpu);
7d0f84aa	366	val = PSCI_RET_SUCCESS;
aa024c2f MZ	367	break;
aa024c2f MZ	368	case KVM_PSCI_FN_CPU_ON:
6c7a5dce	369	mutex_lock(&kvm->lock);
aa024c2f	370	val = kvm_psci_vcpu_on(vcpu);
6c7a5dce	371	mutex_unlock(&kvm->lock);
aa024c2f	372	break;
e2d99736	373	default:
7d0f84aa	374	val = PSCI_RET_NOT_SUPPORTED;
aa024c2f	375	break;
aa024c2f MZ	376	}
aa024c2f MZ	377
153dc8be	378	smccc_set_retval(vcpu, val, 0, 0, 0);
e8e7fcc5	379	return 1;
aa024c2f	380	}
7d0f84aa AP	381
	382	/**
	383	* kvm_psci_call - handle PSCI call if r0 value is in range
	384	* @vcpu: Pointer to the VCPU struct
	385	*
	386	* Handle PSCI calls from guests through traps from HVC instructions.
e8e7fcc5 AP	387	* The calling convention is similar to SMC calls to the secure world
	388	* where the function number is placed in r0.
	389	*
	390	* This function returns: > 0 (success), 0 (success but exit to user
	391	* space), and < 0 (errors)
	392	*
	393	* Errors:
	394	* -EINVAL: Unrecognized PSCI function
7d0f84aa	395	*/
e8e7fcc5	396	int kvm_psci_call(struct kvm_vcpu *vcpu)
7d0f84aa AP	397	{
7d0f84aa AP	398	switch (kvm_psci_version(vcpu)) {
6a2b29fa MZ	399	case KVM_ARM_PSCI_1_0:
6a2b29fa MZ	400	return kvm_psci_1_0_call(vcpu);
7d0f84aa AP	401	case KVM_ARM_PSCI_0_2:
	402	return kvm_psci_0_2_call(vcpu);
	403	case KVM_ARM_PSCI_0_1:
	404	return kvm_psci_0_1_call(vcpu);
	405	default:
e8e7fcc5	406	return -EINVAL;
7d0f84aa AP	407	};
7d0f84aa AP	408	}