xref: /dpdk/drivers/net/nfp/nfpcore/nfp_hwinfo.c (revision b6de43530dfa30cbf6b70857e3835099701063d4)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2018 Netronome Systems, Inc.
3  * All rights reserved.
4  */
5 
6 /*
7  * Parse the hwinfo table that the ARM firmware builds in the ARM scratch SRAM
8  * after chip reset.
9  *
10  * Examples of the fields:
11  *   me.count = 40
12  *   me.mask = 0x7f_ffff_ffff
13  *
14  *   me.count is the total number of MEs on the system.
15  *   me.mask is the bitmask of MEs that are available for application usage.
16  *
17  *   (ie, in this example, ME 39 has been reserved by boardconfig.)
18  */
19 
20 #include "nfp_hwinfo.h"
21 
22 #include "nfp_crc.h"
23 #include "nfp_logs.h"
24 #include "nfp_resource.h"
25 
26 #define HWINFO_SIZE_MIN    0x100
27 
28 /*
29  * The Hardware Info Table defines the properties of the system.
30  *
31  * HWInfo v1 Table (fixed size)
32  *
33  * 0x0000: uint32_t version        Hardware Info Table version (1.0)
34  * 0x0004: uint32_t size           Total size of the table, including the
35  *                                     CRC32 (IEEE 802.3)
36  * 0x0008: uint32_t jumptab        Offset of key/value table
37  * 0x000c: uint32_t keys           Total number of keys in the key/value table
38  * NNNNNN:                         Key/value jump table and string data
39  * (size - 4): uint32_t crc32      CRC32 (same as IEEE 802.3, POSIX csum, etc)
40  *                                     CRC32("",0) = ~0, CRC32("a",1) = 0x48C279FE
41  *
42  * HWInfo v2 Table (variable size)
43  *
44  * 0x0000: uint32_t version        Hardware Info Table version (2.0)
45  * 0x0004: uint32_t size           Current size of the data area, excluding CRC32
46  * 0x0008: uint32_t limit          Maximum size of the table
47  * 0x000c: uint32_t reserved       Unused, set to zero
48  * NNNNNN:                         Key/value data
49  * (size - 4): uint32_t crc32      CRC32 (same as IEEE 802.3, POSIX csum, etc)
50  *                                     CRC32("",0) = ~0, CRC32("a",1) = 0x48C279FE
51  *
52  * If the HWInfo table is in the process of being updated, the low bit of
53  * version will be set.
54  *
55  * HWInfo v1 Key/Value Table
56  * -------------------------
57  *
58  *  The key/value table is a set of offsets to ASCIIZ strings which have
59  *  been strcmp(3) sorted (yes, please use bsearch(3) on the table).
60  *
61  *  All keys are guaranteed to be unique.
62  *
63  * N+0: uint32_t key_1        Offset to the first key
64  * N+4: uint32_t val_1        Offset to the first value
65  * N+8: uint32_t key_2        Offset to the second key
66  * N+c: uint32_t val_2        Offset to the second value
67  * ...
68  *
69  * HWInfo v2 Key/Value Table
70  * -------------------------
71  *
72  * Packed UTF8Z strings, ie 'key1\000value1\000key2\000value2\000'
73  * Unsorted.
74  *
75  * Note: Only the HwInfo v2 Table be supported now.
76  */
77 
78 #define NFP_HWINFO_VERSION_1 ('H' << 24 | 'I' << 16 | 1 << 8 | 0 << 1 | 0)
79 #define NFP_HWINFO_VERSION_2 ('H' << 24 | 'I' << 16 | 2 << 8 | 0 << 1 | 0)
80 #define NFP_HWINFO_VERSION_UPDATING    RTE_BIT32(0)
81 
82 struct nfp_hwinfo {
83 	uint8_t start[0];
84 
85 	uint32_t version;
86 	uint32_t size;
87 
88 	/* V2 specific fields */
89 	uint32_t limit;
90 	uint32_t resv;
91 
92 	char data[];
93 };
94 
95 static bool
96 nfp_hwinfo_is_updating(struct nfp_hwinfo *hwinfo)
97 {
98 	return hwinfo->version & NFP_HWINFO_VERSION_UPDATING;
99 }
100 
101 static int
102 nfp_hwinfo_db_walk(struct nfp_hwinfo *hwinfo,
103 		uint32_t size)
104 {
105 	const char *key;
106 	const char *val;
107 	const char *end = hwinfo->data + size;
108 
109 	for (key = hwinfo->data; *key != 0 && key < end;
110 			key = val + strlen(val) + 1) {
111 		val = key + strlen(key) + 1;
112 		if (val >= end) {
113 			PMD_DRV_LOG(ERR, "Bad HWINFO - overflowing value.");
114 			return -EINVAL;
115 		}
116 
117 		if (val + strlen(val) + 1 > end) {
118 			PMD_DRV_LOG(ERR, "Bad HWINFO - overflowing value.");
119 			return -EINVAL;
120 		}
121 	}
122 
123 	return 0;
124 }
125 
126 static int
127 nfp_hwinfo_db_validate(struct nfp_hwinfo *db,
128 		uint32_t len)
129 {
130 	uint32_t *crc;
131 	uint32_t size;
132 	uint32_t new_crc;
133 
134 	size = db->size;
135 	if (size > len) {
136 		PMD_DRV_LOG(ERR, "Unsupported hwinfo size %u > %u.", size, len);
137 		return -EINVAL;
138 	}
139 
140 	size -= sizeof(uint32_t);
141 	new_crc = nfp_crc32_posix((char *)db, size);
142 	crc = (uint32_t *)(db->start + size);
143 	if (new_crc != *crc) {
144 		PMD_DRV_LOG(ERR, "CRC mismatch, calculated %#x, expected %#x.",
145 				new_crc, *crc);
146 		return -EINVAL;
147 	}
148 
149 	return nfp_hwinfo_db_walk(db, size);
150 }
151 
152 static struct nfp_hwinfo *
153 nfp_hwinfo_try_fetch(struct nfp_cpp *cpp,
154 		size_t *cpp_size)
155 {
156 	int err;
157 	void *res;
158 	uint8_t *db;
159 	uint32_t cpp_id;
160 	uint64_t cpp_addr;
161 	struct nfp_hwinfo *header;
162 
163 	res = nfp_resource_acquire(cpp, NFP_RESOURCE_NFP_HWINFO);
164 	if (res == NULL) {
165 		PMD_DRV_LOG(ERR, "HWInfo - acquire resource failed.");
166 		return NULL;
167 	}
168 
169 	cpp_id = nfp_resource_cpp_id(res);
170 	cpp_addr = nfp_resource_address(res);
171 	*cpp_size = nfp_resource_size(res);
172 
173 	nfp_resource_release(res);
174 
175 	if (*cpp_size < HWINFO_SIZE_MIN)
176 		return NULL;
177 
178 	db = malloc(*cpp_size + 1);
179 	if (db == NULL)
180 		return NULL;
181 
182 	err = nfp_cpp_read(cpp, cpp_id, cpp_addr, db, *cpp_size);
183 	if (err != (int)*cpp_size) {
184 		PMD_DRV_LOG(ERR, "HWInfo - CPP read error %d.", err);
185 		goto exit_free;
186 	}
187 
188 	header = (struct nfp_hwinfo *)db;
189 	if (nfp_hwinfo_is_updating(header))
190 		goto exit_free;
191 
192 	if (header->version != NFP_HWINFO_VERSION_2) {
193 		PMD_DRV_LOG(ERR, "Unknown HWInfo version: %#08x.",
194 				header->version);
195 		goto exit_free;
196 	}
197 
198 	/* NULL-terminate for safety */
199 	db[*cpp_size] = '\0';
200 
201 	return (struct nfp_hwinfo *)db;
202 
203 exit_free:
204 	free(db);
205 	return NULL;
206 }
207 
208 static struct nfp_hwinfo *
209 nfp_hwinfo_fetch(struct nfp_cpp *cpp,
210 		size_t *hwdb_size)
211 {
212 	int count = 0;
213 	struct timespec wait;
214 	struct nfp_hwinfo *db;
215 
216 	wait.tv_sec = 0;
217 	wait.tv_nsec = 10000000;    /* 10ms */
218 
219 	for (;;) {
220 		db = nfp_hwinfo_try_fetch(cpp, hwdb_size);
221 		if (db != NULL)
222 			return db;
223 
224 		nanosleep(&wait, NULL);
225 		if (count++ > 200) {    /* 10ms * 200 = 2s */
226 			PMD_DRV_LOG(ERR, "NFP access error.");
227 			return NULL;
228 		}
229 	}
230 }
231 
232 struct nfp_hwinfo *
233 nfp_hwinfo_read(struct nfp_cpp *cpp)
234 {
235 	int err;
236 	size_t hwdb_size = 0;
237 	struct nfp_hwinfo *db;
238 
239 	db = nfp_hwinfo_fetch(cpp, &hwdb_size);
240 	if (db == NULL)
241 		return NULL;
242 
243 	err = nfp_hwinfo_db_validate(db, hwdb_size);
244 	if (err != 0) {
245 		free(db);
246 		return NULL;
247 	}
248 
249 	return db;
250 }
251 
252 /**
253  * Find a value in the HWInfo table by name
254  *
255  * @param hwinfo
256  *   NFP HWInfo table
257  * @param lookup
258  *   HWInfo name to search for
259  *
260  * @return
261  *   Value of the HWInfo name, or NULL
262  */
263 const char *
264 nfp_hwinfo_lookup(struct nfp_hwinfo *hwinfo,
265 		const char *lookup)
266 {
267 	const char *key;
268 	const char *val;
269 	const char *end;
270 
271 	if (hwinfo == NULL || lookup == NULL)
272 		return NULL;
273 
274 	end = hwinfo->data + hwinfo->size - sizeof(uint32_t);
275 
276 	for (key = hwinfo->data; *key != 0 && key < end;
277 			key = val + strlen(val) + 1) {
278 		val = key + strlen(key) + 1;
279 
280 		if (strcmp(key, lookup) == 0)
281 			return val;
282 	}
283 
284 	return NULL;
285 }
286