/*
 * Copyright (c) 2006-2021, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2021-05-18     Bernard      port from FreeBSD
 */

/*-
 * Copyright (c) 2016-2017 Ruslan Bukin <br@bsdpad.com>
 * All rights reserved.
 * Copyright (c) 2019 Mitchell Horne <mhorne@FreeBSD.org>
 *
 * Portions of this software were developed by SRI International and the
 * University of Cambridge Computer Laboratory under DARPA/AFRL contract
 * FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research programme.
 *
 * Portions of this software were developed by the University of Cambridge
 * Computer Laboratory as part of the CTSRD Project, with support from the
 * UK Higher Education Innovation Fund (HEIF).
 *
 * 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 THE 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 THE 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.
 *
 * $FreeBSD$
 */

#ifndef _MACHINE_SBI_H_
#define _MACHINE_SBI_H_

#include <stdint.h>
#include <rtdef.h>

/* SBI Specification Version */
#define SBI_SPEC_VERS_MAJOR_OFFSET  24
#define SBI_SPEC_VERS_MAJOR_MASK    (0x7F << SBI_SPEC_VERS_MAJOR_OFFSET)
#define SBI_SPEC_VERS_MINOR_OFFSET  0
#define SBI_SPEC_VERS_MINOR_MASK    (0xFFFFFF << SBI_SPEC_VERS_MINOR_OFFSET)

/* SBI Implementation IDs */
#define SBI_IMPL_ID_BBL         0
#define SBI_IMPL_ID_OPENSBI     1
#define SBI_IMPL_ID_XVISOR      2
#define SBI_IMPL_ID_KVM         3
#define SBI_IMPL_ID_RUSTSBI     4
#define SBI_IMPL_ID_DIOSIX      5

/* SBI Error Codes */
#define SBI_SUCCESS                 0
#define SBI_ERR_FAILURE             -1
#define SBI_ERR_NOT_SUPPORTED       -2
#define SBI_ERR_INVALID_PARAM       -3
#define SBI_ERR_DENIED              -4
#define SBI_ERR_INVALID_ADDRESS     -5
#define SBI_ERR_ALREADY_AVAILABLE   -6

/* SBI Base Extension */
#define SBI_EXT_ID_BASE             0x10
#define SBI_BASE_GET_SPEC_VERSION   0
#define SBI_BASE_GET_IMPL_ID        1
#define SBI_BASE_GET_IMPL_VERSION   2
#define SBI_BASE_PROBE_EXTENSION    3
#define SBI_BASE_GET_MVENDORID      4
#define SBI_BASE_GET_MARCHID        5
#define SBI_BASE_GET_MIMPID         6

/* Timer (TIME) Extension */
#define SBI_EXT_ID_TIME         0x54494D45
#define SBI_TIME_SET_TIMER      0

/* IPI (IPI) Extension */
#define SBI_EXT_ID_IPI          0x735049
#define SBI_IPI_SEND_IPI        0

/* RFENCE (RFNC) Extension */
#define SBI_EXT_ID_RFNC                     0x52464E43
#define SBI_RFNC_REMOTE_FENCE_I             0
#define SBI_RFNC_REMOTE_SFENCE_VMA          1
#define SBI_RFNC_REMOTE_SFENCE_VMA_ASID     2
#define SBI_RFNC_REMOTE_HFENCE_GVMA_VMID    3
#define SBI_RFNC_REMOTE_HFENCE_GVMA         4
#define SBI_RFNC_REMOTE_HFENCE_VVMA_ASID    5
#define SBI_RFNC_REMOTE_HFENCE_VVMA         6

/* Hart State Management (HSM) Extension */
#define SBI_EXT_ID_HSM                  0x48534D
#define SBI_HSM_HART_START              0
#define SBI_HSM_HART_STOP               1
#define SBI_HSM_HART_STATUS             2
#define  SBI_HSM_STATUS_STARTED         0
#define  SBI_HSM_STATUS_STOPPED         1
#define  SBI_HSM_STATUS_START_PENDING   2
#define  SBI_HSM_STATUS_STOP_PENDING    3

/* Legacy Extensions */
#define SBI_SET_TIMER               0
#define SBI_CONSOLE_PUTCHAR         1
#define SBI_CONSOLE_GETCHAR         2
#define SBI_CLEAR_IPI               3
#define SBI_SEND_IPI                4
#define SBI_REMOTE_FENCE_I          5
#define SBI_REMOTE_SFENCE_VMA       6
#define SBI_REMOTE_SFENCE_VMA_ASID  7
#define SBI_SHUTDOWN                8

#define SBI_CALL0(e, f)                     SBI_CALL5(e, f, 0, 0, 0, 0, 0)
#define SBI_CALL1(e, f, p1)                 SBI_CALL5(e, f, p1, 0, 0, 0, 0)
#define SBI_CALL2(e, f, p1, p2)             SBI_CALL5(e, f, p1, p2, 0, 0, 0)
#define SBI_CALL3(e, f, p1, p2, p3)         SBI_CALL5(e, f, p1, p2, p3, 0, 0)
#define SBI_CALL4(e, f, p1, p2, p3, p4)     SBI_CALL5(e, f, p1, p2, p3, p4, 0)
#define SBI_CALL5(e, f, p1, p2, p3, p4, p5) sbi_call(e, f, p1, p2, p3, p4, p5)

/*
 * Documentation available at
 * https://github.com/riscv/riscv-sbi-doc/blob/master/riscv-sbi.adoc
 */

struct sbi_ret
{
    long error;
    long value;
};

static __inline struct sbi_ret
sbi_call(uint64_t arg7, uint64_t arg6, uint64_t arg0, uint64_t arg1,
         uint64_t arg2, uint64_t arg3, uint64_t arg4)
{
    struct sbi_ret ret;

    register uintptr_t a0 __asm("a0") = (uintptr_t)(arg0);
    register uintptr_t a1 __asm("a1") = (uintptr_t)(arg1);
    register uintptr_t a2 __asm("a2") = (uintptr_t)(arg2);
    register uintptr_t a3 __asm("a3") = (uintptr_t)(arg3);
    register uintptr_t a4 __asm("a4") = (uintptr_t)(arg4);
    register uintptr_t a6 __asm("a6") = (uintptr_t)(arg6);
    register uintptr_t a7 __asm("a7") = (uintptr_t)(arg7);

    __asm __volatile(\
                     "ecall"                                        \
                     : "+r"(a0), "+r"(a1)                           \
                     : "r"(a2), "r"(a3), "r"(a4), "r"(a6), "r"(a7)  \
                     : "memory");

    ret.error = a0;
    ret.value = a1;
    return (ret);
}

/* Base extension functions and variables. */
extern unsigned long sbi_spec_version;
extern unsigned long sbi_impl_id;
extern unsigned long sbi_impl_version;

static __inline long
sbi_probe_extension(long id)
{
    return (SBI_CALL1(SBI_EXT_ID_BASE, SBI_BASE_PROBE_EXTENSION, id).value);
}

/* TIME extension functions. */
void sbi_set_timer(uint64_t val);

/* IPI extension functions. */
void sbi_send_ipi(const unsigned long *hart_mask);

/* RFENCE extension functions. */
void sbi_remote_fence_i(const unsigned long *hart_mask);
int sbi_remote_sfence_vma(const unsigned long *hart_mask,
                          const unsigned long hart_mask_base,
                          unsigned long start, unsigned long size);
void sbi_remote_sfence_vma_asid(const unsigned long *hart_mask, unsigned long start,
                                unsigned long size, unsigned long asid);

/* Hart State Management extension functions. */

/*
 * Start execution on the specified hart at physical address start_addr. The
 * register a0 will contain the hart's ID, and a1 will contain the value of
 * priv.
 */
int sbi_hsm_hart_start(unsigned long hart, unsigned long start_addr, unsigned long priv);

/*
 * Stop execution on the current hart. Interrupts should be disabled, or this
 * function may return.
 */
void sbi_hsm_hart_stop(void);

/*
 * Get the execution status of the specified hart. The status will be one of:
 *  - SBI_HSM_STATUS_STARTED
 *  - SBI_HSM_STATUS_STOPPED
 *  - SBI_HSM_STATUS_START_PENDING
 *  - SBI_HSM_STATUS_STOP_PENDING
 */
int sbi_hsm_hart_status(unsigned long hart);

/* Legacy extension functions. */
static __inline void
sbi_console_putchar(int ch)
{
    (void)SBI_CALL1(SBI_CONSOLE_PUTCHAR, 0, ch);
}

static __inline int
sbi_console_getchar(void)
{
    /*
     * XXX: The "error" is returned here because legacy SBI functions
     * continue to return their value in a0.
     */
    return (SBI_CALL0(SBI_CONSOLE_GETCHAR, 0).error);
}

static __inline void
sbi_shutdown(void)
{
    (void)SBI_CALL0(SBI_SHUTDOWN, 0);
}

void sbi_print_version(void);
void sbi_init(void);

#endif /* !_MACHINE_SBI_H_ */
