/*-
 * Copyright (c) 2018 The FreeBSD Foundation
 *
 * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
 * under sponsorship from the FreeBSD Foundation.
 *
 * 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.
 *
 * 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.
 */

#include <sys/cdefs.h>

#include <machine/specialreg.h>
#include <machine/cpufunc.h>

static uint32_t cpu_feature, cpu_feature2;
static uint32_t cpu_stdext_feature, cpu_stdext_feature2;

static void
ifunc_init(const Elf_Auxinfo *aux __unused)
{
        u_int cpuid_supported, p[4];

        __asm __volatile(
            "   pushfl\n"
            "   popl    %%eax\n"
            "   movl    %%eax,%%ecx\n"
            "   xorl    $0x200000,%%eax\n"
            "   pushl   %%eax\n"
            "   popfl\n"
            "   pushfl\n"
            "   popl    %%eax\n"
            "   xorl    %%eax,%%ecx\n"
            "   je      1f\n"
            "   movl    $1,%0\n"
            "   jmp     2f\n"
            "1: movl    $0,%0\n"
            "2:\n"
            : "=r" (cpuid_supported) : : "eax", "ecx", "cc");
        if (cpuid_supported) {
                do_cpuid(1, p);
                cpu_feature = p[3];
                cpu_feature2 = p[2];
                do_cpuid(0, p);
                if (p[0] >= 7) {
                        cpuid_count(7, 0, p);
                        cpu_stdext_feature = p[1];
                        cpu_stdext_feature2 = p[2];
                } else {
                        cpu_stdext_feature = 0;
                        cpu_stdext_feature2 = 0;
                }
        } else {
                cpu_feature = 0;
                cpu_feature2 = 0;
                cpu_stdext_feature = 0;
                cpu_stdext_feature2 = 0;
        }
}

static void
crt1_handle_rel(const Elf_Rel *r)
{
        Elf_Addr *where, target;

        switch (ELF_R_TYPE(r->r_info)) {
        case R_386_IRELATIVE:
                where = (Elf_Addr *)r->r_offset;
                target = ((Elf_Addr (*)(uint32_t, uint32_t, uint32_t,
                    uint32_t))*where)(cpu_feature, cpu_feature2,
                    cpu_stdext_feature, cpu_stdext_feature2);
                *where = target;
                break;
        }
}