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                 net_ip = string_to_ip("127.0.0.1");
  33                 net_server_ip = net_ip;
  34         }
  35         return ret;
  36 }
  37
  38 static int sb_eth_raw_send(struct udevice *dev, void *packet, int length)
  39 {
  40         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
  41
  42         debug("eth_sandbox_raw: Send packet %d\n", length);
  43
  44         if (priv->local) {
  45                 struct ethernet_hdr *eth = packet;
  46
  47                 if (ntohs(eth->et_protlen) == PROT_ARP) {
  48                         struct arp_hdr *arp = packet + ETHER_HDR_SIZE;
  49
  50                         /**
  51                          * localhost works on a higher-level API in Linux than
  52                          * ARP packets, so fake it
  53                          */
  54                         arp_ip = net_read_ip(&arp->ar_tpa);
  55                         reply_arp = 1;
  56                         return 0;
  57                 }
  58                 packet += ETHER_HDR_SIZE;
  59                 length -= ETHER_HDR_SIZE;
  60         }
  61         return sandbox_eth_raw_os_send(packet, length, priv);
  62 }
  63
  64 static int sb_eth_raw_recv(struct udevice *dev, int flags, uchar **packetp)
  65 {
  66         struct eth_pdata *pdata = dev_get_platdata(dev);
  67         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
  68         int retval = 0;
  69         int length;
  70
  71         if (reply_arp) {
  72                 struct arp_hdr *arp = (void *)net_rx_packets[0] +
  73                         ETHER_HDR_SIZE;
  74
  75                 /*
  76                  * Fake an ARP response. The u-boot network stack is sending an
  77                  * ARP request (to find the MAC address to address the actual
  78                  * packet to) and requires an ARP response to continue. Since
  79                  * this is the localhost interface, there is no Etherent level
  80                  * traffic at all, so there is no way to send an ARP request or
  81                  * to get a response. For this reason we fake the response to
  82                  * make the u-boot network stack happy.
  83                  */
  84                 arp->ar_hrd = htons(ARP_ETHER);
  85                 arp->ar_pro = htons(PROT_IP);
  86                 arp->ar_hln = ARP_HLEN;
  87                 arp->ar_pln = ARP_PLEN;
  88                 arp->ar_op = htons(ARPOP_REPLY);
  89                 /* Any non-zero MAC address will work */
  90                 memset(&arp->ar_sha, 0x01, ARP_HLEN);
  91                 /* Use whatever IP we were looking for (always 127.0.0.1?) */
  92                 net_write_ip(&arp->ar_spa, arp_ip);
  93                 memcpy(&arp->ar_tha, pdata->enetaddr, ARP_HLEN);
  94                 net_write_ip(&arp->ar_tpa, net_ip);
  95                 length = ARP_HDR_SIZE;
  96         } else {
  97                 /* If local, the Ethernet header won't be included; skip it */
  98                 uchar *pktptr = priv->local ?
  99                         net_rx_packets[0] + ETHER_HDR_SIZE : net_rx_packets[0];
 100
 101                 retval = sandbox_eth_raw_os_recv(pktptr, &length, priv);
 102         }
 103
 104         if (!retval && length) {
 105                 if (priv->local) {
 106                         struct ethernet_hdr *eth = (void *)net_rx_packets[0];
 107
 108                         /* Fill in enough of the missing Ethernet header */
 109                         memcpy(eth->et_dest, pdata->enetaddr, ARP_HLEN);
 110                         memset(eth->et_src, 0x01, ARP_HLEN);
 111                         eth->et_protlen = htons(reply_arp ? PROT_ARP : PROT_IP);
 112                         reply_arp = 0;
 113                         length += ETHER_HDR_SIZE;
 114                 }
 115
 116                 debug("eth_sandbox_raw: received packet %d\n",
 117                       length);
 118                 *packetp = net_rx_packets[0];
 119                 return length;
 120         }
 121         return retval;
 122 }
 123
 124 static void sb_eth_raw_stop(struct udevice *dev)
 125 {
 126         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
 127
 128         debug("eth_sandbox_raw: Stop\n");
 129
 130         sandbox_eth_raw_os_stop(priv);
 131 }
 132
 133 static int sb_eth_raw_read_rom_hwaddr(struct udevice *dev)
 134 {
 135         struct eth_pdata *pdata = dev_get_platdata(dev);
 136
 137         net_random_ethaddr(pdata->enetaddr);
 138
 139         return 0;
 140 }
 141
 142 static const struct eth_ops sb_eth_raw_ops = {
 143         .start                  = sb_eth_raw_start,
 144         .send                   = sb_eth_raw_send,
 145         .recv                   = sb_eth_raw_recv,
 146         .stop                   = sb_eth_raw_stop,
 147         .read_rom_hwaddr        = sb_eth_raw_read_rom_hwaddr,
 148 };
 149
 150 static int sb_eth_raw_ofdata_to_platdata(struct udevice *dev)
 151 {
 152         struct eth_pdata *pdata = dev_get_platdata(dev);
 153         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
 154         const char *ifname;
 155         int ret;
 156
 157         pdata->iobase = dev_read_addr(dev);
 158
 159         ifname = dev_read_string(dev, "host-raw-interface");
 160         if (ifname) {
 161                 strncpy(priv->host_ifname, ifname, IFNAMSIZ);
 162                 printf(": Using %s from DT\n", priv->host_ifname);
 163         }
 164         if (dev_read_u32(dev, "host-raw-interface-idx",
 165                          &priv->host_ifindex) < 0) {
 166                 priv->host_ifindex = 0;
 167         } else {
 168                 ret = sandbox_eth_raw_os_idx_to_name(priv);
 169                 if (ret < 0)
 170                         return ret;
 171                 printf(": Using interface index %d from DT (%s)\n",
 172                        priv->host_ifindex, priv->host_ifname);
 173         }
 174
 175         ret = sandbox_eth_raw_os_is_local(priv->host_ifname);
 176         if (ret < 0)
 177                 return ret;
 178         priv->local = ret;
 179
 180         return 0;
 181 }
 182
 183 static const struct udevice_id sb_eth_raw_ids[] = {
 184         { .compatible = "sandbox,eth-raw" },
 185         { }
 186 };
 187
 188 U_BOOT_DRIVER(eth_sandbox_raw) = {
 189         .name   = "eth_sandbox_raw",
 190         .id     = UCLASS_ETH,
 191         .of_match = sb_eth_raw_ids,
 192         .ofdata_to_platdata = sb_eth_raw_ofdata_to_platdata,
 193         .ops    = &sb_eth_raw_ops,
 194         .priv_auto_alloc_size = sizeof(struct eth_sandbox_raw_priv),
 195         .platdata_auto_alloc_size = sizeof(struct eth_pdata),
 196 };