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 <log.h>
  10 #include <asm/eth-raw-os.h>
  11 #include <common.h>
  12 #include <dm.h>
  13 #include <env.h>
  14 #include <malloc.h>
  15 #include <net.h>
  16
  17 DECLARE_GLOBAL_DATA_PTR;
  18
  19 static int reply_arp;
  20 static struct in_addr arp_ip;
  21
  22 static int sb_eth_raw_start(struct udevice *dev)
  23 {
  24         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
  25         struct eth_pdata *pdata = dev_get_plat(dev);
  26         int ret;
  27
  28         debug("eth_sandbox_raw: Start\n");
  29
  30         ret = sandbox_eth_raw_os_start(priv, pdata->enetaddr);
  31         if (priv->local) {
  32                 env_set("ipaddr", "127.0.0.1");
  33                 env_set("serverip", "127.0.0.1");
  34                 net_ip = string_to_ip("127.0.0.1");
  35                 net_server_ip = net_ip;
  36         }
  37         return ret;
  38 }
  39
  40 static int sb_eth_raw_send(struct udevice *dev, void *packet, int length)
  41 {
  42         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
  43
  44         debug("eth_sandbox_raw: Send packet %d\n", length);
  45
  46         if (priv->local) {
  47                 struct ethernet_hdr *eth = packet;
  48
  49                 if (ntohs(eth->et_protlen) == PROT_ARP) {
  50                         struct arp_hdr *arp = packet + ETHER_HDR_SIZE;
  51
  52                         /**
  53                          * localhost works on a higher-level API in Linux than
  54                          * ARP packets, so fake it
  55                          */
  56                         arp_ip = net_read_ip(&arp->ar_tpa);
  57                         reply_arp = 1;
  58                         return 0;
  59                 }
  60                 packet += ETHER_HDR_SIZE;
  61                 length -= ETHER_HDR_SIZE;
  62         }
  63         return sandbox_eth_raw_os_send(packet, length, priv);
  64 }
  65
  66 static int sb_eth_raw_recv(struct udevice *dev, int flags, uchar **packetp)
  67 {
  68         struct eth_pdata *pdata = dev_get_plat(dev);
  69         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
  70         int retval = 0;
  71         int length;
  72
  73         if (reply_arp) {
  74                 struct arp_hdr *arp = (void *)net_rx_packets[0] +
  75                         ETHER_HDR_SIZE;
  76
  77                 /*
  78                  * Fake an ARP response. The u-boot network stack is sending an
  79                  * ARP request (to find the MAC address to address the actual
  80                  * packet to) and requires an ARP response to continue. Since
  81                  * this is the localhost interface, there is no Etherent level
  82                  * traffic at all, so there is no way to send an ARP request or
  83                  * to get a response. For this reason we fake the response to
  84                  * make the u-boot network stack happy.
  85                  */
  86                 arp->ar_hrd = htons(ARP_ETHER);
  87                 arp->ar_pro = htons(PROT_IP);
  88                 arp->ar_hln = ARP_HLEN;
  89                 arp->ar_pln = ARP_PLEN;
  90                 arp->ar_op = htons(ARPOP_REPLY);
  91                 /* Any non-zero MAC address will work */
  92                 memset(&arp->ar_sha, 0x01, ARP_HLEN);
  93                 /* Use whatever IP we were looking for (always 127.0.0.1?) */
  94                 net_write_ip(&arp->ar_spa, arp_ip);
  95                 memcpy(&arp->ar_tha, pdata->enetaddr, ARP_HLEN);
  96                 net_write_ip(&arp->ar_tpa, net_ip);
  97                 length = ARP_HDR_SIZE;
  98         } else {
  99                 /* If local, the Ethernet header won't be included; skip it */
 100                 uchar *pktptr = priv->local ?
 101                         net_rx_packets[0] + ETHER_HDR_SIZE : net_rx_packets[0];
 102
 103                 retval = sandbox_eth_raw_os_recv(pktptr, &length, priv);
 104         }
 105
 106         if (!retval && length) {
 107                 if (priv->local) {
 108                         struct ethernet_hdr *eth = (void *)net_rx_packets[0];
 109
 110                         /* Fill in enough of the missing Ethernet header */
 111                         memcpy(eth->et_dest, pdata->enetaddr, ARP_HLEN);
 112                         memset(eth->et_src, 0x01, ARP_HLEN);
 113                         eth->et_protlen = htons(reply_arp ? PROT_ARP : PROT_IP);
 114                         reply_arp = 0;
 115                         length += ETHER_HDR_SIZE;
 116                 }
 117
 118                 debug("eth_sandbox_raw: received packet %d\n",
 119                       length);
 120                 *packetp = net_rx_packets[0];
 121                 return length;
 122         }
 123         return retval;
 124 }
 125
 126 static void sb_eth_raw_stop(struct udevice *dev)
 127 {
 128         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
 129
 130         debug("eth_sandbox_raw: Stop\n");
 131
 132         sandbox_eth_raw_os_stop(priv);
 133 }
 134
 135 static int sb_eth_raw_read_rom_hwaddr(struct udevice *dev)
 136 {
 137         struct eth_pdata *pdata = dev_get_plat(dev);
 138
 139         net_random_ethaddr(pdata->enetaddr);
 140
 141         return 0;
 142 }
 143
 144 static const struct eth_ops sb_eth_raw_ops = {
 145         .start                  = sb_eth_raw_start,
 146         .send                   = sb_eth_raw_send,
 147         .recv                   = sb_eth_raw_recv,
 148         .stop                   = sb_eth_raw_stop,
 149         .read_rom_hwaddr        = sb_eth_raw_read_rom_hwaddr,
 150 };
 151
 152 static int sb_eth_raw_of_to_plat(struct udevice *dev)
 153 {
 154         struct eth_pdata *pdata = dev_get_plat(dev);
 155         struct eth_sandbox_raw_priv *priv = dev_get_priv(dev);
 156         const char *ifname;
 157         int ret;
 158
 159         pdata->iobase = dev_read_addr(dev);
 160
 161         ifname = dev_read_string(dev, "host-raw-interface");
 162         if (ifname) {
 163                 strncpy(priv->host_ifname, ifname, IFNAMSIZ);
 164                 printf(": Using %s from DT\n", priv->host_ifname);
 165         }
 166         if (dev_read_u32(dev, "host-raw-interface-idx",
 167                          &priv->host_ifindex) < 0) {
 168                 priv->host_ifindex = 0;
 169         } else {
 170                 ret = sandbox_eth_raw_os_idx_to_name(priv);
 171                 if (ret < 0)
 172                         return ret;
 173                 printf(": Using interface index %d from DT (%s)\n",
 174                        priv->host_ifindex, priv->host_ifname);
 175         }
 176
 177         ret = sandbox_eth_raw_os_is_local(priv->host_ifname);
 178         if (ret < 0)
 179                 return ret;
 180         priv->local = ret;
 181
 182         return 0;
 183 }
 184
 185 static const struct udevice_id sb_eth_raw_ids[] = {
 186         { .compatible = "sandbox,eth-raw" },
 187         { }
 188 };
 189
 190 U_BOOT_DRIVER(eth_sandbox_raw) = {
 191         .name   = "eth_sandbox_raw",
 192         .id     = UCLASS_ETH,
 193         .of_match = sb_eth_raw_ids,
 194         .of_to_plat = sb_eth_raw_of_to_plat,
 195         .ops    = &sb_eth_raw_ops,
 196         .priv_auto      = sizeof(struct eth_sandbox_raw_priv),
 197         .plat_auto      = sizeof(struct eth_pdata),
 198 };