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