drivers/atm/nicstarmac.copyright

   1 /* nicstar.c  v0.22  Jawaid Bazyar (bazyar@hypermall.com)
   2  * nicstar.c, M. Welsh (matt.welsh@cl.cam.ac.uk)
   3  *
   4  * Hacked October, 1997 by Jawaid Bazyar, Interlink Advertising Services Inc.
   5  *      http://www.hypermall.com/
   6  * 10/1/97 - commented out CFG_PHYIE bit - we don't care when the PHY
   7  *      interrupts us (except possibly for removal/insertion of the cable?)
   8  * 10/4/97 - began heavy inline documentation of the code. Corrected typos
   9  *      and spelling mistakes.
  10  * 10/5/97 - added code to handle PHY interrupts, disable PHY on
  11  *      loss of link, and correctly re-enable PHY when link is
  12  *      re-established. (put back CFG_PHYIE)
  13  *
  14  *   Modified to work with the IDT7721 nicstar -- AAL5 (tested) only.
  15  *
  16  * R. D. Rechenmacher <ron@fnal.gov>, Aug. 6, 1997
  17  *
  18  * Linux driver for the IDT77201 NICStAR PCI ATM controller.
  19  * PHY component is expected to be 155 Mbps S/UNI-Lite or IDT 77155;
  20  * see init_nicstar() for PHY initialization to change this. This driver
  21  * expects the Linux ATM stack to support scatter-gather lists
  22  * (skb->atm.iovcnt != 0) for Rx skb's passed to vcc->push.
  23  *
  24  * Implementing minimal-copy of received data:
  25  *   IDT always receives data into a small buffer, then large buffers
  26  *     as needed. This means that data must always be copied to create
  27  *     the linear buffer needed by most non-ATM protocol stacks (e.g. IP)
  28  *     Fix is simple: make large buffers large enough to hold entire
  29  *     SDU, and leave <small_buffer_data> bytes empty at the start. Then
  30  *     copy small buffer contents to head of large buffer.
  31  *   Trick is to avoid fragmenting Linux, due to need for a lot of large
  32  *     buffers. This is done by 2 things:
  33  *       1) skb->destructor / skb->atm.recycle_buffer
  34  *            combined, allow nicstar_free_rx_skb to be called to
  35  *            recycle large data buffers
  36  *       2) skb_clone of received buffers
  37  *   See nicstar_free_rx_skb and linearize_buffer for implementation
  38  *     details.
  39  *
  40  *
  41  *
  42  * Copyright (c) 1996 University of Cambridge Computer Laboratory
  43  *
  44  *   This program is free software; you can redistribute it and/or modify
  45  *   it under the terms of the GNU General Public License as published by
  46  *   the Free Software Foundation; either version 2 of the License, or
  47  *   (at your option) any later version.
  48  *
  49  *   This program is distributed in the hope that it will be useful,
  50  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  51  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  52  *   GNU General Public License for more details.
  53  *
  54  *   You should have received a copy of the GNU General Public License
  55  *   along with this program; if not, write to the Free Software
  56  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  57  *
  58  * M. Welsh, 6 July 1996
  59  *
  60  *
  61  */