/*
 * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
 * All rights reserved.
 *
 * 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.
 * 3. Neither the name of Hyra nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 THE COPYRIGHT OWNER 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 _MACHINE_IPI_H_
#define _MACHINE_IPI_H_

#include <sys/types.h>
#include <machine/cpu.h>
#include <machine/lapic.h>

/* Fixed IPI IDs */
#define IPI_HALT   0
#define IPI_TLB    1

/*
 * Represents an interprocessor interrupt
 * handler.
 *
 * @cookie: Used to verifying an instance
 * @id: IPI ID (identifies the IPI)
 * @mask: If set, IPIs are ignored
 * @handler: Handler routine
 */
struct cpu_ipi {
    uint16_t cookie;
    uint8_t id;
    int(*handler)(struct cpu_ipi *ipi);
};

/*
 * Represents an interrupt vector for a
 * specific IPI
 *
 * @ipi: IPIs associated with this vector
 * @cookie: Used to verify an instance
 * @nipi: Number of IPIs associated
 * @vec: System interrupt vector number
 */
struct ipi_vector {
    struct cpu_ipi ipi[IPI_PER_VEC];
    uint16_t cookie;
    uint8_t nipi;
    uint8_t vec;
};

int md_ipi_alloc(struct cpu_ipi **res);
int md_ipi_send(struct cpu_info *ci);
void md_ipi_init(void);

/*
 * Get the vector an IPI belongs to
 *
 * @ipi: IPI to check
 */
__always_inline static inline uint8_t
ipi_vector(uint8_t ipi)
{
    return ipi / N_IPIVEC;
}

/*
 * Get the handler index an IPI belongs
 * to
 *
 * @ipi: IPI to check
 */
__always_inline static inline uint8_t
ipi_index(uint8_t ipi)
{
    return ipi % (sizeof(ipi_pend_t) * 8);
}

__always_inline static inline int
cpu_ipi_send(struct cpu_info *ci, uint8_t ipi)
{
    uint8_t vec = ipi_vector(ipi);
    uint8_t idx = ipi_index(ipi);

    ci->ipi_pending[vec] |= BIT(idx);
    return md_ipi_send(ci);
}

#endif  /* !_MACHINE_IPI_H_ */