/*
* $Id$
*
* 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.driver.net.via_rhine;
import org.apache.log4j.Logger;
import static org.jnode.driver.net.via_rhine.ViaRhineConstants.PKT_BUF_SZ;
import org.jnode.system.resource.MemoryResource;
import org.jnode.system.resource.ResourceManager;
import org.vmmagic.unboxed.Address;
/**
* @author Levente S\u00e1ntha
*/
class ViaRhineDesc {
private static final int OWN_BIT_MASK = 0x80000000;
protected final Logger log = Logger.getLogger(getClass());
byte[] desc;
int descOffs;
MemoryResource descMr;
byte[] data;
int dataOffs;
MemoryResource dataMr;
int descAddr;
public ViaRhineDesc(ResourceManager rm) {
desc = new byte[16 + 32];
descMr = rm.asMemoryResource(desc);
Address descma = descMr.getAddress();
descOffs = align32(descma);
descAddr = descma.add(descOffs).toInt();
data = new byte[PKT_BUF_SZ + 32];
dataMr = rm.asMemoryResource(data);
Address datma = dataMr.getAddress();
dataOffs = align32(datma);
descMr.setInt(descOffs + 8, datma.add(dataOffs).toInt());
}
void setOwnBit() {
descMr.setInt(descOffs, descMr.getInt(descOffs) | OWN_BIT_MASK);
}
boolean isOwnBit() {
return (descMr.getInt(descOffs) & OWN_BIT_MASK) != 0;
}
void setNextDescAddr(int addr) {
descMr.setInt(descOffs + 12, addr);
}
/**
* Align an addres on 32-byte boundary.
*
* @param addr the address
* @return the the aligned address offset relative to addr
*/
private int align32(Address addr) {
int i_addr = addr.toInt();
int offs = 0;
while ((i_addr & 31) != 0) {
i_addr++;
offs++;
}
return offs;
}
}