drivers/net/sandbox-raw.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2015 National Instruments
   4  *
   5  * (C) Copyright 2015
   6  * Joe Hershberger <joe.hershberger@ni.com>
   7  */
   8
   9 #include <asm/eth-raw-os.h>
  10 #include <common.h>
  11 #include <dm.h>
  12 #include <malloc.h>
  13 #include <net.h>
  14
  15 DECLARE_GLOBAL_DATA_PTR;
  16
  17 static int reply_arp;
  18 static struct in_addr arp_ip;
  19
  20 static int sb_eth_raw_start(struct udevice *dev)
  21 {
  22         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
  23         struct eth_pdata *pdata = dev_get_platdata(dev);
  24         int ret;
  25
  26         debug("eth_sandbox_raw: Start\n");
  27
  28         ret = sandbox_eth_raw_os_start(priv, pdata->enetaddr);
  29         if (priv->local) {
  30                 env_set("ipaddr", "127.0.0.1");
  31                 env_set("serverip", "127.0.0.1");
  32         }
  33         return ret;
  34 }
  35
  36 static int sb_eth_raw_send(struct udevice *dev, void *packet, int length)
  37 {
  38         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
  39
  40         debug("eth_sandbox_raw: Send packet %d\n", length);
  41
  42         if (priv->local) {
  43                 struct ethernet_hdr *eth = packet;
  44
  45                 if (ntohs(eth->et_protlen) == PROT_ARP) {
  46                         struct arp_hdr *arp = packet + ETHER_HDR_SIZE;
  47
  48                         /**
  49                          * localhost works on a higher-level API in Linux than
  50                          * ARP packets, so fake it
  51                          */
  52                         arp_ip = net_read_ip(&arp->ar_tpa);
  53                         reply_arp = 1;
  54                         return 0;
  55                 }
  56                 packet += ETHER_HDR_SIZE;
  57                 length -= ETHER_HDR_SIZE;
  58         }
  59         return sandbox_eth_raw_os_send(packet, length, priv);
  60 }
  61
  62 static int sb_eth_raw_recv(struct udevice *dev, int flags, uchar **packetp)
  63 {
  64         struct eth_pdata *pdata = dev_get_platdata(dev);
  65         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
  66         int retval = 0;
  67         int length;
  68
  69         if (reply_arp) {
  70                 struct arp_hdr *arp = (void *)net_rx_packets[0] +
  71                         ETHER_HDR_SIZE;
  72
  73                 /*
  74                  * Fake an ARP response. The u-boot network stack is sending an
  75                  * ARP request (to find the MAC address to address the actual
  76                  * packet to) and requires an ARP response to continue. Since
  77                  * this is the localhost interface, there is no Etherent level
  78                  * traffic at all, so there is no way to send an ARP request or
  79                  * to get a response. For this reason we fake the response to
  80                  * make the u-boot network stack happy.
  81                  */
  82                 arp->ar_hrd = htons(ARP_ETHER);
  83                 arp->ar_pro = htons(PROT_IP);
  84                 arp->ar_hln = ARP_HLEN;
  85                 arp->ar_pln = ARP_PLEN;
  86                 arp->ar_op = htons(ARPOP_REPLY);
  87                 /* Any non-zero MAC address will work */
  88                 memset(&arp->ar_sha, 0x01, ARP_HLEN);
  89                 /* Use whatever IP we were looking for (always 127.0.0.1?) */
  90                 net_write_ip(&arp->ar_spa, arp_ip);
  91                 memcpy(&arp->ar_tha, pdata->enetaddr, ARP_HLEN);
  92                 net_write_ip(&arp->ar_tpa, net_ip);
  93                 length = ARP_HDR_SIZE;
  94         } else {
  95                 /* If local, the Ethernet header won't be included; skip it */
  96                 uchar *pktptr = priv->local ?
  97                         net_rx_packets[0] + ETHER_HDR_SIZE : net_rx_packets[0];
  98
  99                 retval = sandbox_eth_raw_os_recv(pktptr, &length, priv);
 100         }
 101
 102         if (!retval && length) {
 103                 if (priv->local) {
 104                         struct ethernet_hdr *eth = (void *)net_rx_packets[0];
 105
 106                         /* Fill in enough of the missing Ethernet header */
 107                         memcpy(eth->et_dest, pdata->enetaddr, ARP_HLEN);
 108                         memset(eth->et_src, 0x01, ARP_HLEN);
 109                         eth->et_protlen = htons(reply_arp ? PROT_ARP : PROT_IP);
 110                         reply_arp = 0;
 111                         length += ETHER_HDR_SIZE;
 112                 }
 113
 114                 debug("eth_sandbox_raw: received packet %d\n",
 115                       length);
 116                 *packetp = net_rx_packets[0];
 117                 return length;
 118         }
 119         return retval;
 120 }
 121
 122 static void sb_eth_raw_stop(struct udevice *dev)
 123 {
 124         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
 125
 126         debug("eth_sandbox_raw: Stop\n");
 127
 128         sandbox_eth_raw_os_stop(priv);
 129 }
 130
 131 static const struct eth_ops sb_eth_raw_ops = {
 132         .start                  = sb_eth_raw_start,
 133         .send                   = sb_eth_raw_send,
 134         .recv                   = sb_eth_raw_recv,
 135         .stop                   = sb_eth_raw_stop,
 136 };
 137
 138 static int sb_eth_raw_ofdata_to_platdata(struct udevice *dev)
 139 {
 140         struct eth_pdata *pdata = dev_get_platdata(dev);
 141         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
 142         const char *ifname;
 143
 144         pdata->iobase = dev_read_addr(dev);
 145
 146         ifname = dev_read_string(dev, "host-raw-interface");
 147         if (ifname) {
 148                 strncpy(priv->host_ifname, ifname, IFNAMSIZ);
 149                 printf(": Using %s from DT\n", priv->host_ifname);
 150                 if (strcmp(ifname, "lo") == 0)
 151                         priv->local = 1;
 152         }
 153
 154         return 0;
 155 }
 156
 157 static const struct udevice_id sb_eth_raw_ids[] = {
 158         { .compatible = "sandbox,eth-raw" },
 159         { }
 160 };
 161
 162 U_BOOT_DRIVER(eth_sandbox_raw) = {
 163         .name   = "eth_sandbox_raw",
 164         .id     = UCLASS_ETH,
 165         .of_match = sb_eth_raw_ids,
 166         .ofdata_to_platdata = sb_eth_raw_ofdata_to_platdata,
 167         .ops    = &sb_eth_raw_ops,
 168         .priv_auto_alloc_size = sizeof(struct eth_sandbox_raw_priv),
 169         .platdata_auto_alloc_size = sizeof(struct eth_pdata),
 170 };