1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright Gavin Shan, IBM Corporation 2016.
4 */
5
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/init.h>
9 #include <linux/etherdevice.h>
10 #include <linux/netdevice.h>
11 #include <linux/skbuff.h>
12
13 #include <net/ncsi.h>
14 #include <net/net_namespace.h>
15 #include <net/sock.h>
16 #include <net/genetlink.h>
17
18 #include "internal.h"
19 #include "ncsi-pkt.h"
20
21 static const int padding_bytes = 26;
22
23 u32 ncsi_calculate_checksum(unsigned char *data, int len)
24 {
25 u32 checksum = 0;
26 int i;
27
28 for (i = 0; i < len; i += 2)
29 checksum += (((u32)data[i] << 8) | data[i + 1]);
30
31 checksum = (~checksum + 1);
32 return checksum;
33 }
34
35 /* This function should be called after the data area has been
36 * populated completely.
37 */
38 static void ncsi_cmd_build_header(struct ncsi_pkt_hdr *h,
39 struct ncsi_cmd_arg *nca)
40 {
41 u32 checksum;
42 __be32 *pchecksum;
43
44 h->mc_id = 0;
45 h->revision = NCSI_PKT_REVISION;
46 h->reserved = 0;
47 h->id = nca->id;
48 h->type = nca->type;
49 h->channel = NCSI_TO_CHANNEL(nca->package,
50 nca->channel);
51 h->length = htons(nca->payload);
52 h->reserved1[0] = 0;
53 h->reserved1[1] = 0;
54
55 /* Fill with calculated checksum */
56 checksum = ncsi_calculate_checksum((unsigned char *)h,
57 sizeof(*h) + nca->payload);
58 pchecksum = (__be32 *)((void *)h + sizeof(struct ncsi_pkt_hdr) +
59 ALIGN(nca->payload, 4));
60 *pchecksum = htonl(checksum);
61 }
62
63 static int ncsi_cmd_handler_default(struct sk_buff *skb,
64 struct ncsi_cmd_arg *nca)
65 {
66 struct ncsi_cmd_pkt *cmd;
67
68 cmd = skb_put_zero(skb, sizeof(*cmd));
69 ncsi_cmd_build_header(&cmd->cmd.common, nca);
70
71 return 0;
72 }
73
74 static int ncsi_cmd_handler_sp(struct sk_buff *skb,
75 struct ncsi_cmd_arg *nca)
76 {
77 struct ncsi_cmd_sp_pkt *cmd;
78
79 cmd = skb_put_zero(skb, sizeof(*cmd));
80 cmd->hw_arbitration = nca->bytes[0];
81 ncsi_cmd_build_header(&cmd->cmd.common, nca);
82
83 return 0;
84 }
85
86 static int ncsi_cmd_handler_dc(struct sk_buff *skb,
87 struct ncsi_cmd_arg *nca)
88 {
89 struct ncsi_cmd_dc_pkt *cmd;
90
91 cmd = skb_put_zero(skb, sizeof(*cmd));
92 cmd->ald = nca->bytes[0];
93 ncsi_cmd_build_header(&cmd->cmd.common, nca);
94
95 return 0;
96 }
97
98 static int ncsi_cmd_handler_rc(struct sk_buff *skb,
99 struct ncsi_cmd_arg *nca)
100 {
101 struct ncsi_cmd_rc_pkt *cmd;
102
103 cmd = skb_put_zero(skb, sizeof(*cmd));
104 ncsi_cmd_build_header(&cmd->cmd.common, nca);
105
106 return 0;
107 }
108
109 static int ncsi_cmd_handler_ae(struct sk_buff *skb,
110 struct ncsi_cmd_arg *nca)
111 {
112 struct ncsi_cmd_ae_pkt *cmd;
113
114 cmd = skb_put_zero(skb, sizeof(*cmd));
115 cmd->mc_id = nca->bytes[0];
116 cmd->mode = htonl(nca->dwords[1]);
117 ncsi_cmd_build_header(&cmd->cmd.common, nca);
118
119 return 0;
120 }
121
122 static int ncsi_cmd_handler_sl(struct sk_buff *skb,
123 struct ncsi_cmd_arg *nca)
124 {
125 struct ncsi_cmd_sl_pkt *cmd;
126
127 cmd = skb_put_zero(skb, sizeof(*cmd));
128 cmd->mode = htonl(nca->dwords[0]);
129 cmd->oem_mode = htonl(nca->dwords[1]);
130 ncsi_cmd_build_header(&cmd->cmd.common, nca);
131
132 return 0;
133 }
134
135 static int ncsi_cmd_handler_svf(struct sk_buff *skb,
136 struct ncsi_cmd_arg *nca)
137 {
138 struct ncsi_cmd_svf_pkt *cmd;
139
140 cmd = skb_put_zero(skb, sizeof(*cmd));
141 cmd->vlan = htons(nca->words[1]);
142 cmd->index = nca->bytes[6];
143 cmd->enable = nca->bytes[7];
144 ncsi_cmd_build_header(&cmd->cmd.common, nca);
145
146 return 0;
147 }
148
149 static int ncsi_cmd_handler_ev(struct sk_buff *skb,
150 struct ncsi_cmd_arg *nca)
151 {
152 struct ncsi_cmd_ev_pkt *cmd;
153
154 cmd = skb_put_zero(skb, sizeof(*cmd));
155 cmd->mode = nca->bytes[3];
156 ncsi_cmd_build_header(&cmd->cmd.common, nca);
157
158 return 0;
159 }
160
161 static int ncsi_cmd_handler_sma(struct sk_buff *skb,
162 struct ncsi_cmd_arg *nca)
163 {
164 struct ncsi_cmd_sma_pkt *cmd;
165 int i;
166
167 cmd = skb_put_zero(skb, sizeof(*cmd));
168 for (i = 0; i < 6; i++)
169 cmd->mac[i] = nca->bytes[i];
170 cmd->index = nca->bytes[6];
171 cmd->at_e = nca->bytes[7];
172 ncsi_cmd_build_header(&cmd->cmd.common, nca);
173
174 return 0;
175 }
176
177 static int ncsi_cmd_handler_ebf(struct sk_buff *skb,
178 struct ncsi_cmd_arg *nca)
179 {
180 struct ncsi_cmd_ebf_pkt *cmd;
181
182 cmd = skb_put_zero(skb, sizeof(*cmd));
183 cmd->mode = htonl(nca->dwords[0]);
184 ncsi_cmd_build_header(&cmd->cmd.common, nca);
185
186 return 0;
187 }
188
189 static int ncsi_cmd_handler_egmf(struct sk_buff *skb,
190 struct ncsi_cmd_arg *nca)
191 {
192 struct ncsi_cmd_egmf_pkt *cmd;
193
194 cmd = skb_put_zero(skb, sizeof(*cmd));
195 cmd->mode = htonl(nca->dwords[0]);
196 ncsi_cmd_build_header(&cmd->cmd.common, nca);
197
198 return 0;
199 }
200
201 static int ncsi_cmd_handler_snfc(struct sk_buff *skb,
202 struct ncsi_cmd_arg *nca)
203 {
204 struct ncsi_cmd_snfc_pkt *cmd;
205
206 cmd = skb_put_zero(skb, sizeof(*cmd));
207 cmd->mode = nca->bytes[0];
208 ncsi_cmd_build_header(&cmd->cmd.common, nca);
209
210 return 0;
211 }
212
213 static int ncsi_cmd_handler_oem(struct sk_buff *skb,
214 struct ncsi_cmd_arg *nca)
215 {
216 struct ncsi_cmd_oem_pkt *cmd;
217 unsigned int len;
218 int payload;
219 /* NC-SI spec DSP_0222_1.2.0, section 8.2.2.2
220 * requires payload to be padded with 0 to
221 * 32-bit boundary before the checksum field.
222 * Ensure the padding bytes are accounted for in
223 * skb allocation
224 */
225
226 payload = ALIGN(nca->payload, 4);
227 len = sizeof(struct ncsi_cmd_pkt_hdr) + 4;
228 len += max(payload, padding_bytes);
229
230 cmd = skb_put_zero(skb, len);
231 unsafe_memcpy(&cmd->mfr_id, nca->data, nca->payload,
232 /* skb allocated with enough to load the payload */);
233 ncsi_cmd_build_header(&cmd->cmd.common, nca);
234
235 return 0;
236 }
237
238 static struct ncsi_cmd_handler {
239 unsigned char type;
240 int payload;
241 int (*handler)(struct sk_buff *skb,
242 struct ncsi_cmd_arg *nca);
243 } ncsi_cmd_handlers[] = {
244 { NCSI_PKT_CMD_CIS, 0, ncsi_cmd_handler_default },
245 { NCSI_PKT_CMD_SP, 4, ncsi_cmd_handler_sp },
246 { NCSI_PKT_CMD_DP, 0, ncsi_cmd_handler_default },
247 { NCSI_PKT_CMD_EC, 0, ncsi_cmd_handler_default },
248 { NCSI_PKT_CMD_DC, 4, ncsi_cmd_handler_dc },
249 { NCSI_PKT_CMD_RC, 4, ncsi_cmd_handler_rc },
250 { NCSI_PKT_CMD_ECNT, 0, ncsi_cmd_handler_default },
251 { NCSI_PKT_CMD_DCNT, 0, ncsi_cmd_handler_default },
252 { NCSI_PKT_CMD_AE, 8, ncsi_cmd_handler_ae },
253 { NCSI_PKT_CMD_SL, 8, ncsi_cmd_handler_sl },
254 { NCSI_PKT_CMD_GLS, 0, ncsi_cmd_handler_default },
255 { NCSI_PKT_CMD_SVF, 8, ncsi_cmd_handler_svf },
256 { NCSI_PKT_CMD_EV, 4, ncsi_cmd_handler_ev },
257 { NCSI_PKT_CMD_DV, 0, ncsi_cmd_handler_default },
258 { NCSI_PKT_CMD_SMA, 8, ncsi_cmd_handler_sma },
259 { NCSI_PKT_CMD_EBF, 4, ncsi_cmd_handler_ebf },
260 { NCSI_PKT_CMD_DBF, 0, ncsi_cmd_handler_default },
261 { NCSI_PKT_CMD_EGMF, 4, ncsi_cmd_handler_egmf },
262 { NCSI_PKT_CMD_DGMF, 0, ncsi_cmd_handler_default },
263 { NCSI_PKT_CMD_SNFC, 4, ncsi_cmd_handler_snfc },
264 { NCSI_PKT_CMD_GVI, 0, ncsi_cmd_handler_default },
265 { NCSI_PKT_CMD_GC, 0, ncsi_cmd_handler_default },
266 { NCSI_PKT_CMD_GP, 0, ncsi_cmd_handler_default },
267 { NCSI_PKT_CMD_GCPS, 0, ncsi_cmd_handler_default },
268 { NCSI_PKT_CMD_GNS, 0, ncsi_cmd_handler_default },
269 { NCSI_PKT_CMD_GNPTS, 0, ncsi_cmd_handler_default },
270 { NCSI_PKT_CMD_GPS, 0, ncsi_cmd_handler_default },
271 { NCSI_PKT_CMD_OEM, -1, ncsi_cmd_handler_oem },
272 { NCSI_PKT_CMD_PLDM, 0, NULL },
273 { NCSI_PKT_CMD_GPUUID, 0, ncsi_cmd_handler_default },
274 { NCSI_PKT_CMD_GMCMA, 0, ncsi_cmd_handler_default }
275 };
276
277 static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca)
278 {
279 struct ncsi_dev_priv *ndp = nca->ndp;
280 struct ncsi_dev *nd = &ndp->ndev;
281 struct net_device *dev = nd->dev;
282 int hlen = LL_RESERVED_SPACE(dev);
283 int tlen = dev->needed_tailroom;
284 int payload;
285 int len = hlen + tlen;
286 struct sk_buff *skb;
287 struct ncsi_request *nr;
288
289 nr = ncsi_alloc_request(ndp, nca->req_flags);
290 if (!nr)
291 return NULL;
292
293 /* NCSI command packet has 16-bytes header, payload, 4 bytes checksum.
294 * Payload needs padding so that the checksum field following payload is
295 * aligned to 32-bit boundary.
296 * The packet needs padding if its payload is less than 26 bytes to
297 * meet 64 bytes minimal ethernet frame length.
298 */
299 len += sizeof(struct ncsi_cmd_pkt_hdr) + 4;
300 payload = ALIGN(nca->payload, 4);
301 len += max(payload, padding_bytes);
302
303 /* Allocate skb */
304 skb = alloc_skb(len, GFP_ATOMIC);
305 if (!skb) {
306 ncsi_free_request(nr);
307 return NULL;
308 }
309
310 nr->cmd = skb;
311 skb_reserve(skb, hlen);
312 skb_reset_network_header(skb);
313
314 skb->dev = dev;
315 skb->protocol = htons(ETH_P_NCSI);
316
317 return nr;
318 }
319
320 int ncsi_xmit_cmd(struct ncsi_cmd_arg *nca)
321 {
322 struct ncsi_cmd_handler *nch = NULL;
323 struct ncsi_request *nr;
324 unsigned char type;
325 struct ethhdr *eh;
326 int i, ret;
327
328 /* Use OEM generic handler for Netlink request */
329 if (nca->req_flags == NCSI_REQ_FLAG_NETLINK_DRIVEN)
330 type = NCSI_PKT_CMD_OEM;
331 else
332 type = nca->type;
333
334 /* Search for the handler */
335 for (i = 0; i < ARRAY_SIZE(ncsi_cmd_handlers); i++) {
336 if (ncsi_cmd_handlers[i].type == type) {
337 if (ncsi_cmd_handlers[i].handler)
338 nch = &ncsi_cmd_handlers[i];
339 else
340 nch = NULL;
341
342 break;
343 }
344 }
345
346 if (!nch) {
347 netdev_err(nca->ndp->ndev.dev,
348 "Cannot send packet with type 0x%02x\n", nca->type);
349 return -ENOENT;
350 }
351
352 /* Get packet payload length and allocate the request
353 * It is expected that if length set as negative in
354 * handler structure means caller is initializing it
355 * and setting length in nca before calling xmit function
356 */
357 if (nch->payload >= 0)
358 nca->payload = nch->payload;
359 nr = ncsi_alloc_command(nca);
360 if (!nr)
361 return -ENOMEM;
362
363 /* track netlink information */
364 if (nca->req_flags == NCSI_REQ_FLAG_NETLINK_DRIVEN) {
365 nr->snd_seq = nca->info->snd_seq;
366 nr->snd_portid = nca->info->snd_portid;
367 nr->nlhdr = *nca->info->nlhdr;
368 }
369
370 /* Prepare the packet */
371 nca->id = nr->id;
372 ret = nch->handler(nr->cmd, nca);
373 if (ret) {
374 ncsi_free_request(nr);
375 return ret;
376 }
377
378 /* Fill the ethernet header */
379 eh = skb_push(nr->cmd, sizeof(*eh));
380 eh->h_proto = htons(ETH_P_NCSI);
381 eth_broadcast_addr(eh->h_dest);
382
383 /* If mac address received from device then use it for
384 * source address as unicast address else use broadcast
385 * address as source address
386 */
387 if (nca->ndp->gma_flag == 1)
388 memcpy(eh->h_source, nca->ndp->ndev.dev->dev_addr, ETH_ALEN);
389 else
390 eth_broadcast_addr(eh->h_source);
391
392 /* Start the timer for the request that might not have
393 * corresponding response. Given NCSI is an internal
394 * connection a 1 second delay should be sufficient.
395 */
396 nr->enabled = true;
397 mod_timer(&nr->timer, jiffies + 1 * HZ);
398
399 /* Send NCSI packet */
400 skb_get(nr->cmd);
401 ret = dev_queue_xmit(nr->cmd);
402 if (ret < 0) {
403 ncsi_free_request(nr);
404 return ret;
405 }
406
407 return 0;
408 }
409
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