net/ncsi/ncsi-cmd.c

   1 /*
   2  * Copyright Gavin Shan, IBM Corporation 2016.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/etherdevice.h>
  14 #include <linux/netdevice.h>
  15 #include <linux/skbuff.h>
  16
  17 #include <net/ncsi.h>
  18 #include <net/net_namespace.h>
  19 #include <net/sock.h>
  20
  21 #include "internal.h"
  22 #include "ncsi-pkt.h"
  23
  24 u32 ncsi_calculate_checksum(unsigned char *data, int len)
  25 {
  26         u32 checksum = 0;
  27         int i;
  28
  29         for (i = 0; i < len; i += 2)
  30                 checksum += (((u32)data[i] << 8) | data[i + 1]);
  31
  32         checksum = (~checksum + 1);
  33         return checksum;
  34 }
  35
  36 /* This function should be called after the data area has been
  37  * populated completely.
  38  */
  39 static void ncsi_cmd_build_header(struct ncsi_pkt_hdr *h,
  40                                   struct ncsi_cmd_arg *nca)
  41 {
  42         u32 checksum;
  43         __be32 *pchecksum;
  44
  45         h->mc_id        = 0;
  46         h->revision     = NCSI_PKT_REVISION;
  47         h->reserved     = 0;
  48         h->id           = nca->id;
  49         h->type         = nca->type;
  50         h->channel      = NCSI_TO_CHANNEL(nca->package,
  51                                           nca->channel);
  52         h->length       = htons(nca->payload);
  53         h->reserved1[0] = 0;
  54         h->reserved1[1] = 0;
  55
  56         /* Fill with calculated checksum */
  57         checksum = ncsi_calculate_checksum((unsigned char *)h,
  58                                            sizeof(*h) + nca->payload);
  59         pchecksum = (__be32 *)((void *)h + sizeof(struct ncsi_pkt_hdr) +
  60                     nca->payload);
  61         *pchecksum = htonl(checksum);
  62 }
  63
  64 static int ncsi_cmd_handler_default(struct sk_buff *skb,
  65                                     struct ncsi_cmd_arg *nca)
  66 {
  67         struct ncsi_cmd_pkt *cmd;
  68
  69         cmd = (struct ncsi_cmd_pkt *)skb_put(skb, sizeof(*cmd));
  70         memset(cmd, 0, sizeof(*cmd));
  71         ncsi_cmd_build_header(&cmd->cmd.common, nca);
  72
  73         return 0;
  74 }
  75
  76 static int ncsi_cmd_handler_sp(struct sk_buff *skb,
  77                                struct ncsi_cmd_arg *nca)
  78 {
  79         struct ncsi_cmd_sp_pkt *cmd;
  80
  81         cmd = (struct ncsi_cmd_sp_pkt *)skb_put(skb, sizeof(*cmd));
  82         memset(cmd, 0, sizeof(*cmd));
  83         cmd->hw_arbitration = nca->bytes[0];
  84         ncsi_cmd_build_header(&cmd->cmd.common, nca);
  85
  86         return 0;
  87 }
  88
  89 static int ncsi_cmd_handler_dc(struct sk_buff *skb,
  90                                struct ncsi_cmd_arg *nca)
  91 {
  92         struct ncsi_cmd_dc_pkt *cmd;
  93
  94         cmd = (struct ncsi_cmd_dc_pkt *)skb_put(skb, sizeof(*cmd));
  95         memset(cmd, 0, sizeof(*cmd));
  96         cmd->ald = nca->bytes[0];
  97         ncsi_cmd_build_header(&cmd->cmd.common, nca);
  98
  99         return 0;
 100 }
 101
 102 static int ncsi_cmd_handler_rc(struct sk_buff *skb,
 103                                struct ncsi_cmd_arg *nca)
 104 {
 105         struct ncsi_cmd_rc_pkt *cmd;
 106
 107         cmd = (struct ncsi_cmd_rc_pkt *)skb_put(skb, sizeof(*cmd));
 108         memset(cmd, 0, sizeof(*cmd));
 109         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 110
 111         return 0;
 112 }
 113
 114 static int ncsi_cmd_handler_ae(struct sk_buff *skb,
 115                                struct ncsi_cmd_arg *nca)
 116 {
 117         struct ncsi_cmd_ae_pkt *cmd;
 118
 119         cmd = (struct ncsi_cmd_ae_pkt *)skb_put(skb, sizeof(*cmd));
 120         memset(cmd, 0, sizeof(*cmd));
 121         cmd->mc_id = nca->bytes[0];
 122         cmd->mode = htonl(nca->dwords[1]);
 123         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 124
 125         return 0;
 126 }
 127
 128 static int ncsi_cmd_handler_sl(struct sk_buff *skb,
 129                                struct ncsi_cmd_arg *nca)
 130 {
 131         struct ncsi_cmd_sl_pkt *cmd;
 132
 133         cmd = (struct ncsi_cmd_sl_pkt *)skb_put(skb, sizeof(*cmd));
 134         memset(cmd, 0, sizeof(*cmd));
 135         cmd->mode = htonl(nca->dwords[0]);
 136         cmd->oem_mode = htonl(nca->dwords[1]);
 137         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 138
 139         return 0;
 140 }
 141
 142 static int ncsi_cmd_handler_svf(struct sk_buff *skb,
 143                                 struct ncsi_cmd_arg *nca)
 144 {
 145         struct ncsi_cmd_svf_pkt *cmd;
 146
 147         cmd = (struct ncsi_cmd_svf_pkt *)skb_put(skb, sizeof(*cmd));
 148         memset(cmd, 0, sizeof(*cmd));
 149         cmd->vlan = htons(nca->words[0]);
 150         cmd->index = nca->bytes[2];
 151         cmd->enable = nca->bytes[3];
 152         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 153
 154         return 0;
 155 }
 156
 157 static int ncsi_cmd_handler_ev(struct sk_buff *skb,
 158                                struct ncsi_cmd_arg *nca)
 159 {
 160         struct ncsi_cmd_ev_pkt *cmd;
 161
 162         cmd = (struct ncsi_cmd_ev_pkt *)skb_put(skb, sizeof(*cmd));
 163         memset(cmd, 0, sizeof(*cmd));
 164         cmd->mode = nca->bytes[0];
 165         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 166
 167         return 0;
 168 }
 169
 170 static int ncsi_cmd_handler_sma(struct sk_buff *skb,
 171                                 struct ncsi_cmd_arg *nca)
 172 {
 173         struct ncsi_cmd_sma_pkt *cmd;
 174         int i;
 175
 176         cmd = (struct ncsi_cmd_sma_pkt *)skb_put(skb, sizeof(*cmd));
 177         memset(cmd, 0, sizeof(*cmd));
 178         for (i = 0; i < 6; i++)
 179                 cmd->mac[i] = nca->bytes[i];
 180         cmd->index = nca->bytes[6];
 181         cmd->at_e = nca->bytes[7];
 182         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 183
 184         return 0;
 185 }
 186
 187 static int ncsi_cmd_handler_ebf(struct sk_buff *skb,
 188                                 struct ncsi_cmd_arg *nca)
 189 {
 190         struct ncsi_cmd_ebf_pkt *cmd;
 191
 192         cmd = (struct ncsi_cmd_ebf_pkt *)skb_put(skb, sizeof(*cmd));
 193         memset(cmd, 0, sizeof(*cmd));
 194         cmd->mode = htonl(nca->dwords[0]);
 195         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 196
 197         return 0;
 198 }
 199
 200 static int ncsi_cmd_handler_egmf(struct sk_buff *skb,
 201                                  struct ncsi_cmd_arg *nca)
 202 {
 203         struct ncsi_cmd_egmf_pkt *cmd;
 204
 205         cmd = (struct ncsi_cmd_egmf_pkt *)skb_put(skb, sizeof(*cmd));
 206         memset(cmd, 0, sizeof(*cmd));
 207         cmd->mode = htonl(nca->dwords[0]);
 208         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 209
 210         return 0;
 211 }
 212
 213 static int ncsi_cmd_handler_snfc(struct sk_buff *skb,
 214                                  struct ncsi_cmd_arg *nca)
 215 {
 216         struct ncsi_cmd_snfc_pkt *cmd;
 217
 218         cmd = (struct ncsi_cmd_snfc_pkt *)skb_put(skb, sizeof(*cmd));
 219         memset(cmd, 0, sizeof(*cmd));
 220         cmd->mode = nca->bytes[0];
 221         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 222
 223         return 0;
 224 }
 225
 226 static struct ncsi_cmd_handler {
 227         unsigned char type;
 228         int           payload;
 229         int           (*handler)(struct sk_buff *skb,
 230                                  struct ncsi_cmd_arg *nca);
 231 } ncsi_cmd_handlers[] = {
 232         { NCSI_PKT_CMD_CIS,    0, ncsi_cmd_handler_default },
 233         { NCSI_PKT_CMD_SP,     4, ncsi_cmd_handler_sp      },
 234         { NCSI_PKT_CMD_DP,     0, ncsi_cmd_handler_default },
 235         { NCSI_PKT_CMD_EC,     0, ncsi_cmd_handler_default },
 236         { NCSI_PKT_CMD_DC,     4, ncsi_cmd_handler_dc      },
 237         { NCSI_PKT_CMD_RC,     4, ncsi_cmd_handler_rc      },
 238         { NCSI_PKT_CMD_ECNT,   0, ncsi_cmd_handler_default },
 239         { NCSI_PKT_CMD_DCNT,   0, ncsi_cmd_handler_default },
 240         { NCSI_PKT_CMD_AE,     8, ncsi_cmd_handler_ae      },
 241         { NCSI_PKT_CMD_SL,     8, ncsi_cmd_handler_sl      },
 242         { NCSI_PKT_CMD_GLS,    0, ncsi_cmd_handler_default },
 243         { NCSI_PKT_CMD_SVF,    4, ncsi_cmd_handler_svf     },
 244         { NCSI_PKT_CMD_EV,     4, ncsi_cmd_handler_ev      },
 245         { NCSI_PKT_CMD_DV,     0, ncsi_cmd_handler_default },
 246         { NCSI_PKT_CMD_SMA,    8, ncsi_cmd_handler_sma     },
 247         { NCSI_PKT_CMD_EBF,    4, ncsi_cmd_handler_ebf     },
 248         { NCSI_PKT_CMD_DBF,    0, ncsi_cmd_handler_default },
 249         { NCSI_PKT_CMD_EGMF,   4, ncsi_cmd_handler_egmf    },
 250         { NCSI_PKT_CMD_DGMF,   0, ncsi_cmd_handler_default },
 251         { NCSI_PKT_CMD_SNFC,   4, ncsi_cmd_handler_snfc    },
 252         { NCSI_PKT_CMD_GVI,    0, ncsi_cmd_handler_default },
 253         { NCSI_PKT_CMD_GC,     0, ncsi_cmd_handler_default },
 254         { NCSI_PKT_CMD_GP,     0, ncsi_cmd_handler_default },
 255         { NCSI_PKT_CMD_GCPS,   0, ncsi_cmd_handler_default },
 256         { NCSI_PKT_CMD_GNS,    0, ncsi_cmd_handler_default },
 257         { NCSI_PKT_CMD_GNPTS,  0, ncsi_cmd_handler_default },
 258         { NCSI_PKT_CMD_GPS,    0, ncsi_cmd_handler_default },
 259         { NCSI_PKT_CMD_OEM,    0, NULL                     },
 260         { NCSI_PKT_CMD_PLDM,   0, NULL                     },
 261         { NCSI_PKT_CMD_GPUUID, 0, ncsi_cmd_handler_default }
 262 };
 263
 264 static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca)
 265 {
 266         struct ncsi_dev_priv *ndp = nca->ndp;
 267         struct ncsi_dev *nd = &ndp->ndev;
 268         struct net_device *dev = nd->dev;
 269         int hlen = LL_RESERVED_SPACE(dev);
 270         int tlen = dev->needed_tailroom;
 271         int len = hlen + tlen;
 272         struct sk_buff *skb;
 273         struct ncsi_request *nr;
 274
 275         nr = ncsi_alloc_request(ndp, nca->req_flags);
 276         if (!nr)
 277                 return NULL;
 278
 279         /* NCSI command packet has 16-bytes header, payload, 4 bytes checksum.
 280          * The packet needs padding if its payload is less than 26 bytes to
 281          * meet 64 bytes minimal ethernet frame length.
 282          */
 283         len += sizeof(struct ncsi_cmd_pkt_hdr) + 4;
 284         if (nca->payload < 26)
 285                 len += 26;
 286         else
 287                 len += nca->payload;
 288
 289         /* Allocate skb */
 290         skb = alloc_skb(len, GFP_ATOMIC);
 291         if (!skb) {
 292                 ncsi_free_request(nr);
 293                 return NULL;
 294         }
 295
 296         nr->cmd = skb;
 297         skb_reserve(skb, hlen);
 298         skb_reset_network_header(skb);
 299
 300         skb->dev = dev;
 301         skb->protocol = htons(ETH_P_NCSI);
 302
 303         return nr;
 304 }
 305
 306 int ncsi_xmit_cmd(struct ncsi_cmd_arg *nca)
 307 {
 308         struct ncsi_request *nr;
 309         struct ethhdr *eh;
 310         struct ncsi_cmd_handler *nch = NULL;
 311         int i, ret;
 312
 313         /* Search for the handler */
 314         for (i = 0; i < ARRAY_SIZE(ncsi_cmd_handlers); i++) {
 315                 if (ncsi_cmd_handlers[i].type == nca->type) {
 316                         if (ncsi_cmd_handlers[i].handler)
 317                                 nch = &ncsi_cmd_handlers[i];
 318                         else
 319                                 nch = NULL;
 320
 321                         break;
 322                 }
 323         }
 324
 325         if (!nch) {
 326                 netdev_err(nca->ndp->ndev.dev,
 327                            "Cannot send packet with type 0x%02x\n", nca->type);
 328                 return -ENOENT;
 329         }
 330
 331         /* Get packet payload length and allocate the request */
 332         nca->payload = nch->payload;
 333         nr = ncsi_alloc_command(nca);
 334         if (!nr)
 335                 return -ENOMEM;
 336
 337         /* Prepare the packet */
 338         nca->id = nr->id;
 339         ret = nch->handler(nr->cmd, nca);
 340         if (ret) {
 341                 ncsi_free_request(nr);
 342                 return ret;
 343         }
 344
 345         /* Fill the ethernet header */
 346         eh = (struct ethhdr *)skb_push(nr->cmd, sizeof(*eh));
 347         eh->h_proto = htons(ETH_P_NCSI);
 348         eth_broadcast_addr(eh->h_dest);
 349         eth_broadcast_addr(eh->h_source);
 350
 351         /* Start the timer for the request that might not have
 352          * corresponding response. Given NCSI is an internal
 353          * connection a 1 second delay should be sufficient.
 354          */
 355         nr->enabled = true;
 356         mod_timer(&nr->timer, jiffies + 1 * HZ);
 357
 358         /* Send NCSI packet */
 359         skb_get(nr->cmd);
 360         ret = dev_queue_xmit(nr->cmd);
 361         if (ret < 0) {
 362                 ncsi_free_request(nr);
 363                 return ret;
 364         }
 365
 366         return 0;
 367 }