/*      $NetBSD: acpi_wakeup_low.S,v 1.10 2018/07/14 14:29:40 maxv Exp $        */

/*
 * Copyright (c) 2007 Joerg Sonnenberger <joerg@netbsd.org>
 * Copyright (c) 2001 Takanori Watanabe <takawata@jp.freebsd.org>
 * Copyright (c) 2001 Mitsuru IWASAKI <iwasaki@jp.freebsd.org>
 * 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.
 *
 * 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 "assym.h"
#include <machine/asm.h>
#include <machine/segments.h>
#include <machine/specialreg.h>

        .text

        .p2align 2, 0x90
ENTRY(acpi_md_sleep_exit)
        lgdt    ACPI_SUSPEND_GDT(%r8)

        /* Reload fixed descriptors for new GDT */
        movw    $GSEL(GUDATA_SEL, SEL_UPL),%ax
        movw    %ax,%ds
        movw    %ax,%es
        movw    $GSEL(GDATA_SEL, SEL_KPL),%ax
        movw    %ax,%ss

        /*
         * FS and GS are driven by MSRs, so use NULL for them. If we're
         * returning to a 32bit LWP, %fs/%gs will be restored in
         * INTRFASTEXIT.
         */
        xorw    %ax,%ax
        movw    %ax,%fs
        movw    %ax,%gs

        movl    $MSR_EFER,%ecx
        movl    ACPI_SUSPEND_EFER(%r8),%eax
        movl    $0,%edx
        wrmsr

        movl    $MSR_FSBASE,%ecx
        movl    ACPI_SUSPEND_FS(%r8),%eax
        movl    ACPI_SUSPEND_FS+4(%r8),%edx
        wrmsr

        movl    $MSR_GSBASE,%ecx
        movl    ACPI_SUSPEND_GS(%r8),%eax
        movl    ACPI_SUSPEND_GS+4(%r8),%edx
        wrmsr

        movl    $MSR_KERNELGSBASE,%ecx
        movl    ACPI_SUSPEND_KGS(%r8),%eax
        movl    ACPI_SUSPEND_KGS+4(%r8),%edx
        wrmsr

        movq    ACPI_SUSPEND_CR8(%r8),%rax
        movq    %rax,%cr8
        movq    ACPI_SUSPEND_CR4(%r8),%rax
        movq    %rax,%cr4
        movq    ACPI_SUSPEND_CR3(%r8),%rax
        movq    %rax,%cr3
        movq    ACPI_SUSPEND_CR2(%r8),%rax
        movq    %rax,%cr2
        movq    ACPI_SUSPEND_CR0(%r8),%rax
        movq    %rax,%cr0

        jmp     1f
1:

        movq    CPUVAR(GDT),%rax
        movzwq  ACPI_SUSPEND_TR(%r8),%rdx
        andq    $~0x0200,4(%rax,%rdx, 1)

        ltr     %dx
        lldt    ACPI_SUSPEND_LDT(%r8)
        lidt    ACPI_SUSPEND_IDT(%r8)

        movq    ACPI_SUSPEND_REG+(0*8)(%r8),%rsp
        movq    ACPI_SUSPEND_REG+(1*8)(%r8),%rbx
        movq    ACPI_SUSPEND_REG+(2*8)(%r8),%rbp
        movq    ACPI_SUSPEND_REG+(3*8)(%r8),%r12
        movq    ACPI_SUSPEND_REG+(4*8)(%r8),%r13
        movq    ACPI_SUSPEND_REG+(5*8)(%r8),%r14
        movq    ACPI_SUSPEND_REG+(6*8)(%r8),%r15

        xorq    %rax,%rax

        pushq   ACPI_SUSPEND_REG+(7*8)(%r8)
        popfq
        ret
END(acpi_md_sleep_exit)

        .p2align 2, 0x90
ENTRY(acpi_md_sleep_prepare)
        movq    CPUVAR(SELF),%r8
        movq    %rbx,ACPI_SUSPEND_REG+(1*8)(%r8)
        movq    %rbp,ACPI_SUSPEND_REG+(2*8)(%r8)
        movq    %r12,ACPI_SUSPEND_REG+(3*8)(%r8)
        movq    %r13,ACPI_SUSPEND_REG+(4*8)(%r8)
        movq    %r14,ACPI_SUSPEND_REG+(5*8)(%r8)
        movq    %r15,ACPI_SUSPEND_REG+(6*8)(%r8)

        movq    %cr0,%rax
        movq    %rax,ACPI_SUSPEND_CR0(%r8)
        movq    %cr2,%rax
        movq    %rax,ACPI_SUSPEND_CR2(%r8)
        movq    %cr3,%rax
        movq    %rax,ACPI_SUSPEND_CR3(%r8)
        movq    %cr4,%rax
        movq    %rax,ACPI_SUSPEND_CR4(%r8)
        movq    %cr8,%rax
        movq    %rax,ACPI_SUSPEND_CR8(%r8)

        pushfq
        popq    ACPI_SUSPEND_REG+(7*8)(%r8)

        movq    %rsp,ACPI_SUSPEND_REG+(0*8)(%r8)

        movl    $MSR_FSBASE,%ecx
        rdmsr
        movl    %eax,ACPI_SUSPEND_FS(%r8)
        movl    %edx,ACPI_SUSPEND_FS+4(%r8)

        movl    $MSR_GSBASE,%ecx
        rdmsr
        movl    %eax,ACPI_SUSPEND_GS(%r8)
        movl    %edx,ACPI_SUSPEND_GS+4(%r8)

        movl    $MSR_KERNELGSBASE,%ecx
        rdmsr
        movl    %eax,ACPI_SUSPEND_KGS(%r8)
        movl    %edx,ACPI_SUSPEND_KGS+4(%r8)

        movl    $MSR_EFER,%ecx
        rdmsr
        movl    %eax,ACPI_SUSPEND_EFER(%r8)

        sgdt    ACPI_SUSPEND_GDT(%r8)
        sidt    ACPI_SUSPEND_IDT(%r8)
        sldt    ACPI_SUSPEND_LDT(%r8)
        str     ACPI_SUSPEND_TR(%r8)

        call    acpi_md_sleep_enter
        /* acpi_md_sleep_enter only returns on failure. */
        movl    $-1,%eax
        ret
END(acpi_md_sleep_prepare)