/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2015 Mihai Carabas <mihai.carabas@gmail.com>
 * Copyright (c) 2024 Ruslan Bukin <br@bsdpad.com>
 *
 * This software was developed by the University of Cambridge Computer
 * Laboratory (Department of Computer Science and Technology) under Innovate
 * UK project 105694, "Digital Security by Design (DSbD) Technology Platform
 * Prototype".
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef _VMM_RISCV_H_
#define _VMM_RISCV_H_

#include <machine/reg.h>
#include <machine/pcpu.h>
#include <machine/vmm.h>

#include <riscv/vmm/vmm_vtimer.h>

struct hypregs {
        uint64_t hyp_ra;
        uint64_t hyp_sp;
        uint64_t hyp_gp;
        uint64_t hyp_tp;
        uint64_t hyp_t[7];
        uint64_t hyp_s[12];
        uint64_t hyp_a[8];
        uint64_t hyp_sepc;
        uint64_t hyp_sstatus;
        uint64_t hyp_hstatus;
};

struct hypcsr {
        uint64_t hvip;
        uint64_t vsstatus;
        uint64_t vsie;
        uint64_t vstvec;
        uint64_t vsscratch;
        uint64_t vsepc;
        uint64_t vscause;
        uint64_t vstval;
        uint64_t vsatp;
        uint64_t scounteren;
        uint64_t senvcfg;
};

enum vmm_fence_type {
        VMM_RISCV_FENCE_INVALID = 0,
        VMM_RISCV_FENCE_I,
        VMM_RISCV_FENCE_VMA,
        VMM_RISCV_FENCE_VMA_ASID,
};

struct vmm_fence {
        enum vmm_fence_type type;
        size_t start;
        size_t size;
        uint64_t asid;
};

struct hypctx {
        struct hypregs host_regs;
        struct hypregs guest_regs;
        struct hypcsr guest_csrs;
        uint64_t host_sscratch;
        uint64_t host_stvec;
        uint64_t host_scounteren;
        uint64_t guest_scounteren;
        struct hyp *hyp;
        struct vcpu *vcpu;
        bool has_exception;
        int cpu_id;
        int ipi_pending;
        int interrupts_pending;
        struct vtimer vtimer;

        struct vmm_fence *fence_queue;
        struct mtx fence_queue_mtx;
        int fence_queue_head;
        int fence_queue_tail;
#define FENCE_REQ_I     (1 << 0)
#define FENCE_REQ_VMA   (1 << 1)
        int fence_req;
};

struct hyp {
        struct vm       *vm;
        uint64_t        vmid_generation;
        bool            aplic_attached;
        struct aplic    *aplic;
        struct hypctx   *ctx[];
};

struct hyptrap {
        uint64_t sepc;
        uint64_t scause;
        uint64_t stval;
        uint64_t htval;
        uint64_t htinst;
};

#define dprintf(fmt, ...)

struct hypctx *riscv_get_active_vcpu(void);
void vmm_switch(struct hypctx *);
void vmm_unpriv_trap(struct hyptrap *, uint64_t tmp);
bool vmm_sbi_ecall(struct vcpu *);

void riscv_send_ipi(struct hyp *hyp, cpuset_t *cpus);
int riscv_check_ipi(struct hypctx *hypctx, bool clear);
bool riscv_check_interrupts_pending(struct hypctx *hypctx);

#endif /* !_VMM_RISCV_H_ */