drivers/net/sandbox-raw.c

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