/*
 * $Id$
 *
 * Copyright (C) 2003-2015 JNode.org
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but 
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; If not, write to the Free Software Foundation, Inc., 
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
package org.jnode.vm.x86;

import org.jnode.annotation.Internal;
import org.jnode.annotation.KernelSpace;
import org.vmmagic.unboxed.Address;
import org.vmmagic.unboxed.Word;


/**
 * @author Ewout Prangsma (epr@users.sourceforge.net)
 */
public final class UnsafeX86 {

    /**
     * Copies the bootstrap GDT.
     *
     * @param gdt
     * @return The array length of the required array.
     */
    static final native int getGDT(int[] gdt);

    /**
     * Copies the bootstrap TSS.
     *
     * @param tss
     * @return The array length of the required array.
     */
    static final native int getTSS(int[] tss);

    /**
     * Gets the size required for the bootcode for an application processor.
     *
     * @return The required size in bytes.
     */
    static final native int getAPBootCodeSize();

    /**
     * Prepare the bootcode.
     * This will copy the bootcode into the memory region and patches the
     * appropriate pointers.
     *
     * @param memory
     * @param gdt
     */
    static final native void setupBootCode(Address memory, int[] gdt, int[] tss);

    /**
     * Gets the CR3 register.
     *
     * @return
     */
    static final native Address getCR3();

    /**
     * Read CPU identification data.
     * <p/>
     *
     * @param input  The number to put in EAX
     * @param result An array of length 4 (or longer) where eax, ebx, ecx, edx is stored into.
     * @return 1 on success, 0 otherwise (result == null or result.length less than 4).
     */
    @Internal
    static native int getCPUID(Word input, int[] result);

    /**
     * Read a model specific register
     */
    @KernelSpace
    static native long readMSR(Word index);

    /**
     * Write a model specific register
     */
    @KernelSpace
    static native void writeMSR(Word index, long value);

    /**
     * Gets the address of first entry in the multiboot mmap table.
     *
     * @return
     */
    static final native Address getMultibootMMap();

    /**
     * Gets the number of entries in the multiboot mmap table.
     *
     * @return
     */
    static final native int getMultibootMMapLength();

    public static final native Address getVbeControlInfos();

    public static final native Address getVbeModeInfos();

    /**
     * Merge 32-bit ARGB values at the given memory address.
     *
     * @param src    The source address (points to 32-bit ARGB int's)
     * @param dst    The destination address (points to 32-bit RGB int's)
     * @param length The number of 32-bit int's to merge.
     */
    static final native void setARGB32bppMMX(Address src, Address dst, int length);

    /**
     * Save and restore the MSR's arrays of the current thread.
     */
    public static final native void syncMSRs();

    /**
     * Restore the MSR's arrays of the current thread.
     */
    public static final native void restoreMSRs();

    /**
     * Save the MSR's arrays of the current thread.
     */
    public static final native void saveMSRs();
}