1 /*
2 * Copyright 2009 Solarflare Communications Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25
26 #include "efsys.h"
27 #include "efx.h"
28 #include "efx_types.h"
29 #include "efx_impl.h"
30
31 #if EFSYS_OPT_BOOTCFG
32
33 /*
34 * Maximum size of BOOTCFG block across all nics as understood by SFCgPXE.
35 * A multiple of 0x100 so trailing 0xff characters don't contrinbute to the
36 * checksum.
37 */
38 #define BOOTCFG_MAX_SIZE 0x1000
39
40 #define DHCP_END (uint8_t)0xff
41 #define DHCP_PAD (uint8_t)0
42
43 static __checkReturn uint8_t
44 efx_bootcfg_csum(
45 __in efx_nic_t *enp,
46 __in_bcount(size) caddr_t data,
47 __in size_t size)
48 {
49 _NOTE(ARGUNUSED(enp))
50
51 unsigned int pos;
52 uint8_t checksum = 0;
53
54 for (pos = 0; pos < size; pos++)
55 checksum += data[pos];
56 return (checksum);
57 }
58
59 static __checkReturn int
60 efx_bootcfg_verify(
61 __in efx_nic_t *enp,
62 __in_bcount(size) caddr_t data,
63 __in size_t size,
64 __out size_t *usedp)
65 {
66 size_t offset = 0;
67 size_t used = 0;
68 int rc;
69
70 /* Start parsing tags immediatly after the checksum */
71 for (offset = 1; offset < size; ) {
72 uint8_t tag;
73 uint8_t length;
74
75 /* Consume tag */
76 tag = data[offset];
77 if (tag == DHCP_END) {
78 offset++;
79 used = offset;
80 break;
81 }
82 if (tag == DHCP_PAD) {
83 offset++;
84 continue;
85 }
86
87 /* Consume length */
88 if (offset + 1 >= size) {
89 rc = ENOSPC;
90 goto fail1;
91 }
92 length = data[offset + 1];
93
94 /* Consume *length */
95 if (offset + 1 + length >= size) {
96 rc = ENOSPC;
97 goto fail2;
98 }
99
100 offset += 2 + length;
101 used = offset;
102 }
103
104 /* Checksum the entire sector, including bytes after any DHCP_END */
105 if (efx_bootcfg_csum(enp, data, size) != 0) {
106 rc = EINVAL;
107 goto fail3;
108 }
109
110 if (usedp != NULL)
111 *usedp = used;
112
113 return (0);
114
115 fail3:
116 EFSYS_PROBE(fail3);
117 fail2:
118 EFSYS_PROBE(fail2);
119 fail1:
120 EFSYS_PROBE1(fail1, int, rc);
121
122 return (rc);
123 }
124
125 int
126 efx_bootcfg_read(
127 __in efx_nic_t *enp,
128 __out_bcount(size) caddr_t data,
129 __in size_t size)
130 {
131 uint8_t *payload = NULL;
132 size_t used_bytes;
133 size_t sector_length;
134 int rc;
135
136 rc = efx_nvram_size(enp, EFX_NVRAM_BOOTROM_CFG, §or_length);
137 if (rc != 0)
138 goto fail1;
139
140 /*
141 * We need to read the entire BOOTCFG area to ensure we read all the
142 * tags, because legacy bootcfg sectors are not guaranteed to end with
143 * a DHCP_END character. If the user hasn't supplied a sufficiently
144 * large buffer then use our own buffer.
145 */
146 if (sector_length > BOOTCFG_MAX_SIZE)
147 sector_length = BOOTCFG_MAX_SIZE;
148 if (sector_length > size) {
149 EFSYS_KMEM_ALLOC(enp->en_esip, sector_length, payload);
150 if (payload == NULL) {
151 rc = ENOMEM;
152 goto fail2;
153 }
154 } else
155 payload = (uint8_t *)data;
156
157 if ((rc = efx_nvram_rw_start(enp, EFX_NVRAM_BOOTROM_CFG, NULL)) != 0)
158 goto fail3;
159
160 rc = efx_nvram_read_chunk(enp, EFX_NVRAM_BOOTROM_CFG, 0,
161 (caddr_t)payload, sector_length);
162
163 efx_nvram_rw_finish(enp, EFX_NVRAM_BOOTROM_CFG);
164
165 if (rc != 0)
166 goto fail4;
167
168 /* Verify that the area is correctly formatted and checksummed */
169 rc = efx_bootcfg_verify(enp, (caddr_t)payload, sector_length,
170 &used_bytes);
171 if (rc != 0 || used_bytes == 0) {
172 payload[0] = (uint8_t)~DHCP_END;
173 payload[1] = DHCP_END;
174 used_bytes = 2;
175 }
176
177 EFSYS_ASSERT(used_bytes >= 2); /* checksum and DHCP_END */
178 EFSYS_ASSERT(used_bytes <= sector_length);
179
180 /*
181 * Legacy bootcfg sectors don't terminate with a DHCP_END character.
182 * Modify the returned payload so it does. BOOTCFG_MAX_SIZE is by
183 * definition large enough for any valid (per-port) bootcfg sector,
184 * so reinitialise the sector if there isn't room for the character.
185 */
186 if (payload[used_bytes - 1] != DHCP_END) {
187 if (used_bytes + 1 > sector_length) {
188 payload[0] = 0;
189 used_bytes = 1;
190 }
191
192 payload[used_bytes] = DHCP_END;
193 ++used_bytes;
194 }
195
196 /*
197 * Verify that the user supplied buffer is large enough for the
198 * entire used bootcfg area, then copy into the user supplied buffer.
199 */
200 if (used_bytes > size) {
201 rc = ENOSPC;
202 goto fail5;
203 }
204 if (sector_length > size) {
205 memcpy(data, payload, used_bytes);
206 EFSYS_KMEM_FREE(enp->en_esip, sector_length, payload);
207 }
208
209 /* Zero out the unused portion of the user buffer */
210 if (used_bytes < size)
211 (void) memset(data + used_bytes, 0, size - used_bytes);
212
213 /*
214 * The checksum includes trailing data after any DHCP_END character,
215 * which we've just modified (by truncation or appending DHCP_END).
216 */
217 data[0] -= efx_bootcfg_csum(enp, data, size);
218
219 return (0);
220
221 fail5:
222 EFSYS_PROBE(fail5);
223 fail4:
224 EFSYS_PROBE(fail4);
225 fail3:
226 EFSYS_PROBE(fail3);
227
228 if (sector_length > size)
229 EFSYS_KMEM_FREE(enp->en_esip, sector_length, payload);
230 fail2:
231 EFSYS_PROBE(fail2);
232 fail1:
233 EFSYS_PROBE1(fail1, int, rc);
234
235 return (rc);
236 }
237
238 int
239 efx_bootcfg_write(
240 __in efx_nic_t *enp,
241 __in_bcount(size) caddr_t data,
242 __in size_t size)
243 {
244 uint8_t *chunk;
245 uint8_t checksum;
246 size_t sector_length;
247 size_t chunk_length;
248 size_t used_bytes;
249 size_t offset;
250 size_t remaining;
251 int rc;
252
253 rc = efx_nvram_size(enp, EFX_NVRAM_BOOTROM_CFG, §or_length);
254 if (rc != 0)
255 goto fail1;
256
257 if (sector_length > BOOTCFG_MAX_SIZE)
258 sector_length = BOOTCFG_MAX_SIZE;
259
260 if ((rc = efx_bootcfg_verify(enp, data, size, &used_bytes)) != 0)
261 goto fail2;
262
263 /* The caller *must* terminate their block with a DHCP_END character */
264 EFSYS_ASSERT(used_bytes >= 2); /* checksum and DHCP_END */
265 if ((uint8_t)data[used_bytes - 1] != DHCP_END) {
266 rc = ENOENT;
267 goto fail3;
268 }
269
270 /* Check that the hardware has support for this much data */
271 if (used_bytes > MIN(sector_length, BOOTCFG_MAX_SIZE)) {
272 rc = ENOSPC;
273 goto fail4;
274 }
275
276 rc = efx_nvram_rw_start(enp, EFX_NVRAM_BOOTROM_CFG, &chunk_length);
277 if (rc != 0)
278 goto fail5;
279
280 EFSYS_KMEM_ALLOC(enp->en_esip, chunk_length, chunk);
281 if (chunk == NULL) {
282 rc = ENOMEM;
283 goto fail6;
284 }
285
286 if ((rc = efx_nvram_erase(enp, EFX_NVRAM_BOOTROM_CFG)) != 0)
287 goto fail7;
288
289 /*
290 * Write the entire sector_length bytes of data in chunks. Zero out
291 * all data following the DHCP_END, and adjust the checksum
292 */
293 checksum = efx_bootcfg_csum(enp, data, used_bytes);
294 for (offset = 0; offset < sector_length; offset += remaining) {
295 remaining = MIN(chunk_length, sector_length - offset);
296
297 /* Fill chunk */
298 (void) memset(chunk, 0x0, chunk_length);
299 if (offset < used_bytes)
300 memcpy(chunk, data + offset,
301 MIN(remaining, used_bytes - offset));
302
303 /* Adjust checksum */
304 if (offset == 0)
305 chunk[0] -= checksum;
306
307 if ((rc = efx_nvram_write_chunk(enp, EFX_NVRAM_BOOTROM_CFG,
308 offset, (caddr_t)chunk, remaining)) != 0)
309 goto fail8;
310 }
311
312 efx_nvram_rw_finish(enp, EFX_NVRAM_BOOTROM_CFG);
313
314 EFSYS_KMEM_FREE(enp->en_esip, chunk_length, chunk);
315
316 return (0);
317
318 fail8:
319 EFSYS_PROBE(fail8);
320 fail7:
321 EFSYS_PROBE(fail7);
322
323 EFSYS_KMEM_FREE(enp->en_esip, chunk_length, chunk);
324 fail6:
325 EFSYS_PROBE(fail6);
326
327 efx_nvram_rw_finish(enp, EFX_NVRAM_BOOTROM_CFG);
328 fail5:
329 EFSYS_PROBE(fail5);
330 fail4:
331 EFSYS_PROBE(fail4);
332 fail3:
333 EFSYS_PROBE(fail3);
334 fail2:
335 EFSYS_PROBE(fail2);
336 fail1:
337 EFSYS_PROBE1(fail1, int, rc);
338
339 return (rc);
340 }
341
342 #endif /* EFSYS_OPT_BOOTCFG */