/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
 */

#ifndef __ARM_KVM_HOST_H__
#define __ARM_KVM_HOST_H__

#include <linux/errno.h>
#include <linux/types.h>
#include <linux/kvm_types.h>
#include <asm/cputype.h>
#include <asm/kvm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_mmio.h>
#include <asm/fpstate.h>
#include <kvm/arm_arch_timer.h>

#define __KVM_HAVE_ARCH_INTC_INITIALIZED

#define KVM_USER_MEM_SLOTS 32
#define KVM_HAVE_ONE_REG
#define KVM_HALT_POLL_NS_DEFAULT 500000

#define KVM_VCPU_MAX_FEATURES 2

#include <kvm/arm_vgic.h>


#ifdef CONFIG_ARM_GIC_V3
#define KVM_MAX_VCPUS VGIC_V3_MAX_CPUS
#else
#define KVM_MAX_VCPUS VGIC_V2_MAX_CPUS
#endif

#define KVM_REQ_SLEEP \
        KVM_ARCH_REQ_FLAGS(0, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
#define KVM_REQ_IRQ_PENDING     KVM_ARCH_REQ(1)
#define KVM_REQ_VCPU_RESET      KVM_ARCH_REQ(2)

DECLARE_STATIC_KEY_FALSE(userspace_irqchip_in_use);

static inline int kvm_arm_init_sve(void) { return 0; }

u32 *kvm_vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num, u32 mode);
int __attribute_const__ kvm_target_cpu(void);
int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
void kvm_reset_coprocs(struct kvm_vcpu *vcpu);

struct kvm_vmid {
        /* The VMID generation used for the virt. memory system */
        u64    vmid_gen;
        u32    vmid;
};

struct kvm_arch {
        /* The last vcpu id that ran on each physical CPU */
        int __percpu *last_vcpu_ran;

        /*
         * Anything that is not used directly from assembly code goes
         * here.
         */

        /* The VMID generation used for the virt. memory system */
        struct kvm_vmid vmid;

        /* Stage-2 page table */
        pgd_t *pgd;
        phys_addr_t pgd_phys;

        /* Interrupt controller */
        struct vgic_dist        vgic;
        int max_vcpus;

        /* Mandated version of PSCI */
        u32 psci_version;
};

#define KVM_NR_MEM_OBJS     40

/*
 * We don't want allocation failures within the mmu code, so we preallocate
 * enough memory for a single page fault in a cache.
 */
struct kvm_mmu_memory_cache {
        int nobjs;
        void *objects[KVM_NR_MEM_OBJS];
};

struct kvm_vcpu_fault_info {
        u32 hsr;                /* Hyp Syndrome Register */
        u32 hxfar;              /* Hyp Data/Inst. Fault Address Register */
        u32 hpfar;              /* Hyp IPA Fault Address Register */
};

/*
 * 0 is reserved as an invalid value.
 * Order should be kept in sync with the save/restore code.
 */
enum vcpu_sysreg {
        __INVALID_SYSREG__,
        c0_MPIDR,               /* MultiProcessor ID Register */
        c0_CSSELR,              /* Cache Size Selection Register */
        c1_SCTLR,               /* System Control Register */
        c1_ACTLR,               /* Auxiliary Control Register */
        c1_CPACR,               /* Coprocessor Access Control */
        c2_TTBR0,               /* Translation Table Base Register 0 */
        c2_TTBR0_high,          /* TTBR0 top 32 bits */
        c2_TTBR1,               /* Translation Table Base Register 1 */
        c2_TTBR1_high,          /* TTBR1 top 32 bits */
        c2_TTBCR,               /* Translation Table Base Control R. */
        c3_DACR,                /* Domain Access Control Register */
        c5_DFSR,                /* Data Fault Status Register */
        c5_IFSR,                /* Instruction Fault Status Register */
        c5_ADFSR,               /* Auxilary Data Fault Status R */
        c5_AIFSR,               /* Auxilary Instrunction Fault Status R */
        c6_DFAR,                /* Data Fault Address Register */
        c6_IFAR,                /* Instruction Fault Address Register */
        c7_PAR,                 /* Physical Address Register */
        c7_PAR_high,            /* PAR top 32 bits */
        c9_L2CTLR,              /* Cortex A15/A7 L2 Control Register */
        c10_PRRR,               /* Primary Region Remap Register */
        c10_NMRR,               /* Normal Memory Remap Register */
        c12_VBAR,               /* Vector Base Address Register */
        c13_CID,                /* Context ID Register */
        c13_TID_URW,            /* Thread ID, User R/W */
        c13_TID_URO,            /* Thread ID, User R/O */
        c13_TID_PRIV,           /* Thread ID, Privileged */
        c14_CNTKCTL,            /* Timer Control Register (PL1) */
        c10_AMAIR0,             /* Auxilary Memory Attribute Indirection Reg0 */
        c10_AMAIR1,             /* Auxilary Memory Attribute Indirection Reg1 */
        NR_CP15_REGS            /* Number of regs (incl. invalid) */
};

struct kvm_cpu_context {
        struct kvm_regs gp_regs;
        struct vfp_hard_struct vfp;
        u32 cp15[NR_CP15_REGS];
};

struct kvm_host_data {
        struct kvm_cpu_context host_ctxt;
};

typedef struct kvm_host_data kvm_host_data_t;

static inline void kvm_init_host_cpu_context(struct kvm_cpu_context *cpu_ctxt)
{
        /* The host's MPIDR is immutable, so let's set it up at boot time */
        cpu_ctxt->cp15[c0_MPIDR] = read_cpuid_mpidr();
}

struct vcpu_reset_state {
        unsigned long   pc;
        unsigned long   r0;
        bool            be;
        bool            reset;
};

struct kvm_vcpu_arch {
        struct kvm_cpu_context ctxt;

        int target; /* Processor target */
        DECLARE_BITMAP(features, KVM_VCPU_MAX_FEATURES);

        /* The CPU type we expose to the VM */
        u32 midr;

        /* HYP trapping configuration */
        u32 hcr;

        /* Exception Information */
        struct kvm_vcpu_fault_info fault;

        /* Host FP context */
        struct kvm_cpu_context *host_cpu_context;

        /* VGIC state */
        struct vgic_cpu vgic_cpu;
        struct arch_timer_cpu timer_cpu;

        /*
         * Anything that is not used directly from assembly code goes
         * here.
         */

        /* vcpu power-off state */
        bool power_off;

         /* Don't run the guest (internal implementation need) */
        bool pause;

        /* IO related fields */
        struct kvm_decode mmio_decode;

        /* Cache some mmu pages needed inside spinlock regions */
        struct kvm_mmu_memory_cache mmu_page_cache;

        struct vcpu_reset_state reset_state;

        /* Detect first run of a vcpu */
        bool has_run_once;
};

struct kvm_vm_stat {
        ulong remote_tlb_flush;
};

struct kvm_vcpu_stat {
        u64 halt_successful_poll;
        u64 halt_attempted_poll;
        u64 halt_poll_invalid;
        u64 halt_wakeup;
        u64 hvc_exit_stat;
        u64 wfe_exit_stat;
        u64 wfi_exit_stat;
        u64 mmio_exit_user;
        u64 mmio_exit_kernel;
        u64 exits;
};

#define vcpu_cp15(v,r)  (v)->arch.ctxt.cp15[r]

int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init);
unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);

unsigned long __kvm_call_hyp(void *hypfn, ...);

/*
 * The has_vhe() part doesn't get emitted, but is used for type-checking.
 */
#define kvm_call_hyp(f, ...)                                            \
        do {                                                            \
                if (has_vhe()) {                                        \
                        f(__VA_ARGS__);                                 \
                } else {                                                \
                        __kvm_call_hyp(kvm_ksym_ref(f), ##__VA_ARGS__); \
                }                                                       \
        } while(0)

#define kvm_call_hyp_ret(f, ...)                                        \
        ({                                                              \
                typeof(f(__VA_ARGS__)) ret;                             \
                                                                        \
                if (has_vhe()) {                                        \
                        ret = f(__VA_ARGS__);                           \
                } else {                                                \
                        ret = __kvm_call_hyp(kvm_ksym_ref(f),           \
                                             ##__VA_ARGS__);            \
                }                                                       \
                                                                        \
                ret;                                                    \
        })

void force_vm_exit(const cpumask_t *mask);
int __kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
                              struct kvm_vcpu_events *events);

int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
                              struct kvm_vcpu_events *events);

#define KVM_ARCH_WANT_MMU_NOTIFIER
int kvm_unmap_hva_range(struct kvm *kvm,
                        unsigned long start, unsigned long end);
int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);

unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);

struct kvm_vcpu *kvm_arm_get_running_vcpu(void);
struct kvm_vcpu __percpu **kvm_get_running_vcpus(void);
void kvm_arm_halt_guest(struct kvm *kvm);
void kvm_arm_resume_guest(struct kvm *kvm);

int kvm_arm_copy_coproc_indices(struct kvm_vcpu *vcpu, u64 __user *uindices);
unsigned long kvm_arm_num_coproc_regs(struct kvm_vcpu *vcpu);
int kvm_arm_coproc_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *);
int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *);

int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
                int exception_index);

static inline void handle_exit_early(struct kvm_vcpu *vcpu, struct kvm_run *run,
                                     int exception_index) {}

static inline void __cpu_init_hyp_mode(phys_addr_t pgd_ptr,
                                       unsigned long hyp_stack_ptr,
                                       unsigned long vector_ptr)
{
        /*
         * Call initialization code, and switch to the full blown HYP
         * code. The init code doesn't need to preserve these
         * registers as r0-r3 are already callee saved according to
         * the AAPCS.
         * Note that we slightly misuse the prototype by casting the
         * stack pointer to a void *.

         * The PGDs are always passed as the third argument, in order
         * to be passed into r2-r3 to the init code (yes, this is
         * compliant with the PCS!).
         */

        __kvm_call_hyp((void*)hyp_stack_ptr, vector_ptr, pgd_ptr);
}

static inline void __cpu_init_stage2(void)
{
        kvm_call_hyp(__init_stage2_translation);
}

static inline int kvm_arch_vm_ioctl_check_extension(struct kvm *kvm, long ext)
{
        return 0;
}

int kvm_perf_init(void);
int kvm_perf_teardown(void);

void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot);

struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr);

static inline bool kvm_arch_requires_vhe(void) { return false; }
static inline void kvm_arch_hardware_unsetup(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {}
static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {}

static inline void kvm_arm_init_debug(void) {}
static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {}
static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {}
static inline void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) {}

int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
                               struct kvm_device_attr *attr);
int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu,
                               struct kvm_device_attr *attr);
int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu,
                               struct kvm_device_attr *attr);

/*
 * VFP/NEON switching is all done by the hyp switch code, so no need to
 * coordinate with host context handling for this state:
 */
static inline void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu) {}
static inline void kvm_arch_vcpu_ctxsync_fp(struct kvm_vcpu *vcpu) {}
static inline void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu) {}

static inline void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu) {}
static inline void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu) {}

static inline void kvm_arm_vhe_guest_enter(void) {}
static inline void kvm_arm_vhe_guest_exit(void) {}

#define KVM_BP_HARDEN_UNKNOWN           -1
#define KVM_BP_HARDEN_WA_NEEDED         0
#define KVM_BP_HARDEN_NOT_REQUIRED      1

static inline int kvm_arm_harden_branch_predictor(void)
{
        switch(read_cpuid_part()) {
#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
        case ARM_CPU_PART_BRAHMA_B15:
        case ARM_CPU_PART_CORTEX_A12:
        case ARM_CPU_PART_CORTEX_A15:
        case ARM_CPU_PART_CORTEX_A17:
                return KVM_BP_HARDEN_WA_NEEDED;
#endif
        case ARM_CPU_PART_CORTEX_A7:
                return KVM_BP_HARDEN_NOT_REQUIRED;
        default:
                return KVM_BP_HARDEN_UNKNOWN;
        }
}

#define KVM_SSBD_UNKNOWN                -1
#define KVM_SSBD_FORCE_DISABLE          0
#define KVM_SSBD_KERNEL         1
#define KVM_SSBD_FORCE_ENABLE           2
#define KVM_SSBD_MITIGATED              3

static inline int kvm_arm_have_ssbd(void)
{
        /* No way to detect it yet, pretend it is not there. */
        return KVM_SSBD_UNKNOWN;
}

static inline void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu) {}
static inline void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu) {}

#define __KVM_HAVE_ARCH_VM_ALLOC
struct kvm *kvm_arch_alloc_vm(void);
void kvm_arch_free_vm(struct kvm *kvm);

static inline int kvm_arm_setup_stage2(struct kvm *kvm, unsigned long type)
{
        /*
         * On 32bit ARM, VMs get a static 40bit IPA stage2 setup,
         * so any non-zero value used as type is illegal.
         */
        if (type)
                return -EINVAL;
        return 0;
}

static inline int kvm_arm_vcpu_finalize(struct kvm_vcpu *vcpu, int feature)
{
        return -EINVAL;
}

static inline bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu)
{
        return true;
}

#endif /* __ARM_KVM_HOST_H__ */