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 = skb_put_zero(skb, sizeof(*cmd)); 70 ncsi_cmd_build_header(&cmd->cmd.common, nca); 71 72 return 0; 73 } 74 75 static int ncsi_cmd_handler_sp(struct sk_buff *skb, 76 struct ncsi_cmd_arg *nca) 77 { 78 struct ncsi_cmd_sp_pkt *cmd; 79 80 cmd = skb_put_zero(skb, sizeof(*cmd)); 81 cmd->hw_arbitration = nca->bytes[0]; 82 ncsi_cmd_build_header(&cmd->cmd.common, nca); 83 84 return 0; 85 } 86 87 static int ncsi_cmd_handler_dc(struct sk_buff *skb, 88 struct ncsi_cmd_arg *nca) 89 { 90 struct ncsi_cmd_dc_pkt *cmd; 91 92 cmd = skb_put_zero(skb, sizeof(*cmd)); 93 cmd->ald = nca->bytes[0]; 94 ncsi_cmd_build_header(&cmd->cmd.common, nca); 95 96 return 0; 97 } 98 99 static int ncsi_cmd_handler_rc(struct sk_buff *skb, 100 struct ncsi_cmd_arg *nca) 101 { 102 struct ncsi_cmd_rc_pkt *cmd; 103 104 cmd = skb_put_zero(skb, sizeof(*cmd)); 105 ncsi_cmd_build_header(&cmd->cmd.common, nca); 106 107 return 0; 108 } 109 110 static int ncsi_cmd_handler_ae(struct sk_buff *skb, 111 struct ncsi_cmd_arg *nca) 112 { 113 struct ncsi_cmd_ae_pkt *cmd; 114 115 cmd = skb_put_zero(skb, sizeof(*cmd)); 116 cmd->mc_id = nca->bytes[0]; 117 cmd->mode = htonl(nca->dwords[1]); 118 ncsi_cmd_build_header(&cmd->cmd.common, nca); 119 120 return 0; 121 } 122 123 static int ncsi_cmd_handler_sl(struct sk_buff *skb, 124 struct ncsi_cmd_arg *nca) 125 { 126 struct ncsi_cmd_sl_pkt *cmd; 127 128 cmd = skb_put_zero(skb, sizeof(*cmd)); 129 cmd->mode = htonl(nca->dwords[0]); 130 cmd->oem_mode = htonl(nca->dwords[1]); 131 ncsi_cmd_build_header(&cmd->cmd.common, nca); 132 133 return 0; 134 } 135 136 static int ncsi_cmd_handler_svf(struct sk_buff *skb, 137 struct ncsi_cmd_arg *nca) 138 { 139 struct ncsi_cmd_svf_pkt *cmd; 140 141 cmd = skb_put_zero(skb, sizeof(*cmd)); 142 cmd->vlan = htons(nca->words[0]); 143 cmd->index = nca->bytes[2]; 144 cmd->enable = nca->bytes[3]; 145 ncsi_cmd_build_header(&cmd->cmd.common, nca); 146 147 return 0; 148 } 149 150 static int ncsi_cmd_handler_ev(struct sk_buff *skb, 151 struct ncsi_cmd_arg *nca) 152 { 153 struct ncsi_cmd_ev_pkt *cmd; 154 155 cmd = skb_put_zero(skb, sizeof(*cmd)); 156 cmd->mode = nca->bytes[0]; 157 ncsi_cmd_build_header(&cmd->cmd.common, nca); 158 159 return 0; 160 } 161 162 static int ncsi_cmd_handler_sma(struct sk_buff *skb, 163 struct ncsi_cmd_arg *nca) 164 { 165 struct ncsi_cmd_sma_pkt *cmd; 166 int i; 167 168 cmd = skb_put_zero(skb, sizeof(*cmd)); 169 for (i = 0; i < 6; i++) 170 cmd->mac[i] = nca->bytes[i]; 171 cmd->index = nca->bytes[6]; 172 cmd->at_e = nca->bytes[7]; 173 ncsi_cmd_build_header(&cmd->cmd.common, nca); 174 175 return 0; 176 } 177 178 static int ncsi_cmd_handler_ebf(struct sk_buff *skb, 179 struct ncsi_cmd_arg *nca) 180 { 181 struct ncsi_cmd_ebf_pkt *cmd; 182 183 cmd = skb_put_zero(skb, sizeof(*cmd)); 184 cmd->mode = htonl(nca->dwords[0]); 185 ncsi_cmd_build_header(&cmd->cmd.common, nca); 186 187 return 0; 188 } 189 190 static int ncsi_cmd_handler_egmf(struct sk_buff *skb, 191 struct ncsi_cmd_arg *nca) 192 { 193 struct ncsi_cmd_egmf_pkt *cmd; 194 195 cmd = skb_put_zero(skb, sizeof(*cmd)); 196 cmd->mode = htonl(nca->dwords[0]); 197 ncsi_cmd_build_header(&cmd->cmd.common, nca); 198 199 return 0; 200 } 201 202 static int ncsi_cmd_handler_snfc(struct sk_buff *skb, 203 struct ncsi_cmd_arg *nca) 204 { 205 struct ncsi_cmd_snfc_pkt *cmd; 206 207 cmd = skb_put_zero(skb, sizeof(*cmd)); 208 cmd->mode = nca->bytes[0]; 209 ncsi_cmd_build_header(&cmd->cmd.common, nca); 210 211 return 0; 212 } 213 214 static struct ncsi_cmd_handler { 215 unsigned char type; 216 int payload; 217 int (*handler)(struct sk_buff *skb, 218 struct ncsi_cmd_arg *nca); 219 } ncsi_cmd_handlers[] = { 220 { NCSI_PKT_CMD_CIS, 0, ncsi_cmd_handler_default }, 221 { NCSI_PKT_CMD_SP, 4, ncsi_cmd_handler_sp }, 222 { NCSI_PKT_CMD_DP, 0, ncsi_cmd_handler_default }, 223 { NCSI_PKT_CMD_EC, 0, ncsi_cmd_handler_default }, 224 { NCSI_PKT_CMD_DC, 4, ncsi_cmd_handler_dc }, 225 { NCSI_PKT_CMD_RC, 4, ncsi_cmd_handler_rc }, 226 { NCSI_PKT_CMD_ECNT, 0, ncsi_cmd_handler_default }, 227 { NCSI_PKT_CMD_DCNT, 0, ncsi_cmd_handler_default }, 228 { NCSI_PKT_CMD_AE, 8, ncsi_cmd_handler_ae }, 229 { NCSI_PKT_CMD_SL, 8, ncsi_cmd_handler_sl }, 230 { NCSI_PKT_CMD_GLS, 0, ncsi_cmd_handler_default }, 231 { NCSI_PKT_CMD_SVF, 4, ncsi_cmd_handler_svf }, 232 { NCSI_PKT_CMD_EV, 4, ncsi_cmd_handler_ev }, 233 { NCSI_PKT_CMD_DV, 0, ncsi_cmd_handler_default }, 234 { NCSI_PKT_CMD_SMA, 8, ncsi_cmd_handler_sma }, 235 { NCSI_PKT_CMD_EBF, 4, ncsi_cmd_handler_ebf }, 236 { NCSI_PKT_CMD_DBF, 0, ncsi_cmd_handler_default }, 237 { NCSI_PKT_CMD_EGMF, 4, ncsi_cmd_handler_egmf }, 238 { NCSI_PKT_CMD_DGMF, 0, ncsi_cmd_handler_default }, 239 { NCSI_PKT_CMD_SNFC, 4, ncsi_cmd_handler_snfc }, 240 { NCSI_PKT_CMD_GVI, 0, ncsi_cmd_handler_default }, 241 { NCSI_PKT_CMD_GC, 0, ncsi_cmd_handler_default }, 242 { NCSI_PKT_CMD_GP, 0, ncsi_cmd_handler_default }, 243 { NCSI_PKT_CMD_GCPS, 0, ncsi_cmd_handler_default }, 244 { NCSI_PKT_CMD_GNS, 0, ncsi_cmd_handler_default }, 245 { NCSI_PKT_CMD_GNPTS, 0, ncsi_cmd_handler_default }, 246 { NCSI_PKT_CMD_GPS, 0, ncsi_cmd_handler_default }, 247 { NCSI_PKT_CMD_OEM, 0, NULL }, 248 { NCSI_PKT_CMD_PLDM, 0, NULL }, 249 { NCSI_PKT_CMD_GPUUID, 0, ncsi_cmd_handler_default } 250 }; 251 252 static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca) 253 { 254 struct ncsi_dev_priv *ndp = nca->ndp; 255 struct ncsi_dev *nd = &ndp->ndev; 256 struct net_device *dev = nd->dev; 257 int hlen = LL_RESERVED_SPACE(dev); 258 int tlen = dev->needed_tailroom; 259 int len = hlen + tlen; 260 struct sk_buff *skb; 261 struct ncsi_request *nr; 262 263 nr = ncsi_alloc_request(ndp, nca->req_flags); 264 if (!nr) 265 return NULL; 266 267 /* NCSI command packet has 16-bytes header, payload, 4 bytes checksum. 268 * The packet needs padding if its payload is less than 26 bytes to 269 * meet 64 bytes minimal ethernet frame length. 270 */ 271 len += sizeof(struct ncsi_cmd_pkt_hdr) + 4; 272 if (nca->payload < 26) 273 len += 26; 274 else 275 len += nca->payload; 276 277 /* Allocate skb */ 278 skb = alloc_skb(len, GFP_ATOMIC); 279 if (!skb) { 280 ncsi_free_request(nr); 281 return NULL; 282 } 283 284 nr->cmd = skb; 285 skb_reserve(skb, hlen); 286 skb_reset_network_header(skb); 287 288 skb->dev = dev; 289 skb->protocol = htons(ETH_P_NCSI); 290 291 return nr; 292 } 293 294 int ncsi_xmit_cmd(struct ncsi_cmd_arg *nca) 295 { 296 struct ncsi_request *nr; 297 struct ethhdr *eh; 298 struct ncsi_cmd_handler *nch = NULL; 299 int i, ret; 300 301 /* Search for the handler */ 302 for (i = 0; i < ARRAY_SIZE(ncsi_cmd_handlers); i++) { 303 if (ncsi_cmd_handlers[i].type == nca->type) { 304 if (ncsi_cmd_handlers[i].handler) 305 nch = &ncsi_cmd_handlers[i]; 306 else 307 nch = NULL; 308 309 break; 310 } 311 } 312 313 if (!nch) { 314 netdev_err(nca->ndp->ndev.dev, 315 "Cannot send packet with type 0x%02x\n", nca->type); 316 return -ENOENT; 317 } 318 319 /* Get packet payload length and allocate the request */ 320 nca->payload = nch->payload; 321 nr = ncsi_alloc_command(nca); 322 if (!nr) 323 return -ENOMEM; 324 325 /* Prepare the packet */ 326 nca->id = nr->id; 327 ret = nch->handler(nr->cmd, nca); 328 if (ret) { 329 ncsi_free_request(nr); 330 return ret; 331 } 332 333 /* Fill the ethernet header */ 334 eh = skb_push(nr->cmd, sizeof(*eh)); 335 eh->h_proto = htons(ETH_P_NCSI); 336 eth_broadcast_addr(eh->h_dest); 337 eth_broadcast_addr(eh->h_source); 338 339 /* Start the timer for the request that might not have 340 * corresponding response. Given NCSI is an internal 341 * connection a 1 second delay should be sufficient. 342 */ 343 nr->enabled = true; 344 mod_timer(&nr->timer, jiffies + 1 * HZ); 345 346 /* Send NCSI packet */ 347 skb_get(nr->cmd); 348 ret = dev_queue_xmit(nr->cmd); 349 if (ret < 0) { 350 ncsi_free_request(nr); 351 return ret; 352 } 353 354 return 0; 355 } 356