Orange Pi5 kernel

/*
 * Linux ARCnet driver - RFC1051 ("simple" standard) packet encapsulation
 *
 * Written 1994-1999 by Avery Pennarun.
 * Derived from skeleton.c by Donald Becker.
 *
 * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
 *  for sponsoring the further development of this driver.
 *
 * **********************
 *
 * The original copyright of skeleton.c was as follows:
 *
 * skeleton.c Written 1993 by Donald Becker.
 * Copyright 1993 United States Government as represented by the
 * Director, National Security Agency.  This software may only be used
 * and distributed according to the terms of the GNU General Public License as
 * modified by SRC, incorporated herein by reference.
 *
 * **********************
 *
 * For more details, see drivers/net/arcnet.c
 *
 * **********************
 */
 
#define pr_fmt(fmt) "arcnet:" KBUILD_MODNAME ": " fmt
 
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/init.h>
#include <linux/if_arp.h>
#include <net/arp.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
 
#include "arcdevice.h"
 
static __be16 type_trans(struct sk_buff *skb, struct net_device *dev);
static void rx(struct net_device *dev, int bufnum,
<------>       struct archdr *pkthdr, int length);
static int build_header(struct sk_buff *skb, struct net_device *dev,
<------><------><------>unsigned short type, uint8_t daddr);
static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
<------><------>      int bufnum);
 
static struct ArcProto rfc1051_proto = {
<------>.suffix		= 's',
<------>.mtu		= XMTU - RFC1051_HDR_SIZE,
<------>.is_ip          = 1,
<------>.rx		= rx,
<------>.build_header	= build_header,
<------>.prepare_tx	= prepare_tx,
<------>.continue_tx    = NULL,
<------>.ack_tx         = NULL
};
 
static int __init arcnet_rfc1051_init(void)
{
<------>pr_info("%s\n", "RFC1051 \"simple standard\" (`s') encapsulation support loaded");
 
<------>arc_proto_map[ARC_P_IP_RFC1051]
<------>    = arc_proto_map[ARC_P_ARP_RFC1051]
<------>    = &rfc1051_proto;
 
<------>/* if someone else already owns the broadcast, we won't take it */
<------>if (arc_bcast_proto == arc_proto_default)
<------><------>arc_bcast_proto = &rfc1051_proto;
 
<------>return 0;
}
 
static void __exit arcnet_rfc1051_exit(void)
{
<------>arcnet_unregister_proto(&rfc1051_proto);
}
 
module_init(arcnet_rfc1051_init);
module_exit(arcnet_rfc1051_exit);
 
MODULE_LICENSE("GPL");
 
/* Determine a packet's protocol ID.
 *
 * With ARCnet we have to convert everything to Ethernet-style stuff.
 */
static __be16 type_trans(struct sk_buff *skb, struct net_device *dev)
{
<------>struct archdr *pkt = (struct archdr *)skb->data;
<------>struct arc_rfc1051 *soft = &pkt->soft.rfc1051;
<------>int hdr_size = ARC_HDR_SIZE + RFC1051_HDR_SIZE;
 
<------>/* Pull off the arcnet header. */
<------>skb_reset_mac_header(skb);
<------>skb_pull(skb, hdr_size);
 
<------>if (pkt->hard.dest == 0) {
<------><------>skb->pkt_type = PACKET_BROADCAST;
<------>} else if (dev->flags & IFF_PROMISC) {
<------><------>/* if we're not sending to ourselves :) */
<------><------>if (pkt->hard.dest != dev->dev_addr[0])
<------><------><------>skb->pkt_type = PACKET_OTHERHOST;
<------>}
<------>/* now return the protocol number */
<------>switch (soft->proto) {
<------>case ARC_P_IP_RFC1051:
<------><------>return htons(ETH_P_IP);
<------>case ARC_P_ARP_RFC1051:
<------><------>return htons(ETH_P_ARP);
 
<------>default:
<------><------>dev->stats.rx_errors++;
<------><------>dev->stats.rx_crc_errors++;
<------><------>return 0;
<------>}
 
<------>return htons(ETH_P_IP);
}
 
/* packet receiver */
static void rx(struct net_device *dev, int bufnum,
<------>       struct archdr *pkthdr, int length)
{
<------>struct arcnet_local *lp = netdev_priv(dev);
<------>struct sk_buff *skb;
<------>struct archdr *pkt = pkthdr;
<------>int ofs;
 
<------>arc_printk(D_DURING, dev, "it's a raw packet (length=%d)\n", length);
 
<------>if (length >= MinTU)
<------><------>ofs = 512 - length;
<------>else
<------><------>ofs = 256 - length;
 
<------>skb = alloc_skb(length + ARC_HDR_SIZE, GFP_ATOMIC);
<------>if (!skb) {
<------><------>dev->stats.rx_dropped++;
<------><------>return;
<------>}
<------>skb_put(skb, length + ARC_HDR_SIZE);
<------>skb->dev = dev;
 
<------>pkt = (struct archdr *)skb->data;
 
<------>/* up to sizeof(pkt->soft) has already been copied from the card */
<------>memcpy(pkt, pkthdr, sizeof(struct archdr));
<------>if (length > sizeof(pkt->soft))
<------><------>lp->hw.copy_from_card(dev, bufnum, ofs + sizeof(pkt->soft),
<------><------><------><------>      pkt->soft.raw + sizeof(pkt->soft),
<------><------><------><------>      length - sizeof(pkt->soft));
 
<------>if (BUGLVL(D_SKB))
<------><------>arcnet_dump_skb(dev, skb, "rx");
 
<------>skb->protocol = type_trans(skb, dev);
<------>netif_rx(skb);
}
 
/* Create the ARCnet hard/soft headers for RFC1051 */
static int build_header(struct sk_buff *skb, struct net_device *dev,
<------><------><------>unsigned short type, uint8_t daddr)
{
<------>int hdr_size = ARC_HDR_SIZE + RFC1051_HDR_SIZE;
<------>struct archdr *pkt = skb_push(skb, hdr_size);
<------>struct arc_rfc1051 *soft = &pkt->soft.rfc1051;
 
<------>/* set the protocol ID according to RFC1051 */
<------>switch (type) {
<------>case ETH_P_IP:
<------><------>soft->proto = ARC_P_IP_RFC1051;
<------><------>break;
<------>case ETH_P_ARP:
<------><------>soft->proto = ARC_P_ARP_RFC1051;
<------><------>break;
<------>default:
<------><------>arc_printk(D_NORMAL, dev, "RFC1051: I don't understand protocol %d (%Xh)\n",
<------><------><------>   type, type);
<------><------>dev->stats.tx_errors++;
<------><------>dev->stats.tx_aborted_errors++;
<------><------>return 0;
<------>}
 
<------>/* Set the source hardware address.
<------> *
<------> * This is pretty pointless for most purposes, but it can help in
<------> * debugging.  ARCnet does not allow us to change the source address
<------> * in the actual packet sent.
<------> */
<------>pkt->hard.source = *dev->dev_addr;
 
<------>/* see linux/net/ethernet/eth.c to see where I got the following */
 
<------>if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) {
<------><------>/* FIXME: fill in the last byte of the dest ipaddr here to
<------><------> * better comply with RFC1051 in "noarp" mode.
<------><------> */
<------><------>pkt->hard.dest = 0;
<------><------>return hdr_size;
<------>}
<------>/* otherwise, just fill it in and go! */
<------>pkt->hard.dest = daddr;
 
<------>return hdr_size;	/* success */
}
 
static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
<------><------>      int bufnum)
{
<------>struct arcnet_local *lp = netdev_priv(dev);
<------>struct arc_hardware *hard = &pkt->hard;
<------>int ofs;
 
<------>arc_printk(D_DURING, dev, "prepare_tx: txbufs=%d/%d/%d\n",
<------><------>   lp->next_tx, lp->cur_tx, bufnum);
 
<------>/* hard header is not included in packet length */
<------>length -= ARC_HDR_SIZE;
 
<------>if (length > XMTU) {
<------><------>/* should never happen! other people already check for this. */
<------><------>arc_printk(D_NORMAL, dev, "Bug!  prepare_tx with size %d (> %d)\n",
<------><------><------>   length, XMTU);
<------><------>length = XMTU;
<------>}
<------>if (length > MinTU) {
<------><------>hard->offset[0] = 0;
<------><------>hard->offset[1] = ofs = 512 - length;
<------>} else if (length > MTU) {
<------><------>hard->offset[0] = 0;
<------><------>hard->offset[1] = ofs = 512 - length - 3;
<------>} else {
<------><------>hard->offset[0] = ofs = 256 - length;
<------>}
 
<------>lp->hw.copy_to_card(dev, bufnum, 0, hard, ARC_HDR_SIZE);
<------>lp->hw.copy_to_card(dev, bufnum, ofs, &pkt->soft, length);
 
<------>lp->lastload_dest = hard->dest;
 
<------>return 1;		/* done */
}