/*      $OpenBSD: efiriscv.c,v 1.1 2024/03/26 22:26:04 kettenis Exp $   */

/*
 * Copyright (c) 2024 Mark Kettenis <kettenis@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/param.h>

#include <efi.h>
#include <efiapi.h>

#include "libsa.h"

#include "efiboot.h"

extern EFI_BOOT_SERVICES        *BS;

/* RISC-V UEFI Boot Protocol */

#define RISCV_EFI_BOOT_PROTOCOL_GUID  \
    { 0xccd15fec, 0x6f73, 0x4eec, { 0x83, 0x95, 0x3e, 0x69, 0xe4, 0xb9, 0x40, 0xbf } }

INTERFACE_DECL(_RISCV_EFI_BOOT_PROTOCOL);

typedef
EFI_STATUS
(EFIAPI *EFI_GET_BOOT_HARTID) (
    IN struct _RISCV_EFI_BOOT_PROTOCOL *This,
    OUT UINTN *BootHartId
    );

typedef struct _RISCV_EFI_BOOT_PROTOCOL {
        UINT64                  Revision;
        EFI_GET_BOOT_HARTID     GetBootHartId;
} RISCV_EFI_BOOT_PROTOCOL;

static EFI_GUID                 riscv_guid = RISCV_EFI_BOOT_PROTOCOL_GUID;

int32_t
efi_get_boot_hart_id(void)
{
        EFI_STATUS               status;
        RISCV_EFI_BOOT_PROTOCOL *riscv = NULL;
        UINTN                    hartid;

        status = BS->LocateProtocol(&riscv_guid, NULL, (void **)&riscv);
        if (riscv == NULL || EFI_ERROR(status))
                return -1;

        status = riscv->GetBootHartId(riscv, &hartid);
        if (status == EFI_SUCCESS)
                return hartid;

        return -1;
}