xref: /freebsd/sys/dev/ipmi/ipmi_smbios.c (revision 9336e0699bda8a301cd2bfa37106b6ec5e32012e)
1 /*-
2  * Copyright (c) 2006 IronPort Systems Inc. <ambrisko@ironport.com>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/condvar.h>
34 #include <sys/eventhandler.h>
35 #include <sys/kernel.h>
36 #include <sys/selinfo.h>
37 
38 #include <vm/vm.h>
39 #include <vm/pmap.h>
40 #include <machine/pc/bios.h>
41 
42 #ifdef LOCAL_MODULE
43 #include <ipmi.h>
44 #include <ipmivars.h>
45 #else
46 #include <sys/ipmi.h>
47 #include <dev/ipmi/ipmivars.h>
48 #endif
49 
50 #if __FreeBSD_version < 602110
51 #define	pmap_mapbios		pmap_mapdev
52 #define	pmap_unmapbios		pmap_unmapdev
53 #endif
54 
55 struct smbios_table_entry {
56 	uint8_t		anchor_string[4];
57 	uint8_t		checksum;
58 	uint8_t		length;
59 	uint8_t		major_version;
60 	uint8_t		minor_version;
61 	uint16_t	maximum_structure_size;
62 	uint8_t		entry_point_revision;
63 	uint8_t		formatted_area[5];
64 	uint8_t		DMI_anchor_string[5];
65 	uint8_t		intermediate_checksum;
66 	uint16_t	structure_table_length;
67 	uint32_t	structure_table_address;
68 	uint16_t	number_structures;
69 	uint8_t		BCD_revision;
70 };
71 
72 struct structure_header {
73 	uint8_t		type;
74 	uint8_t		length;
75 	uint16_t	handle;
76 };
77 
78 struct ipmi_entry {
79 	uint8_t		type;
80 	uint8_t		length;
81 	uint16_t	handle;
82 	uint8_t		interface_type;
83 	uint8_t		spec_revision;
84 	uint8_t		i2c_slave_address;
85 	uint8_t		NV_storage_device_address;
86 	uint64_t	base_address;
87 	uint8_t		base_address_modifier;
88 	uint8_t		interrupt_number;
89 };
90 
91 /* Fields in the base_address field of an IPMI entry. */
92 #define	IPMI_BAR_MODE(ba)	((ba) & 0x0000000000000001)
93 #define	IPMI_BAR_ADDR(ba)	((ba) & 0xfffffffffffffffe)
94 
95 /* Fields in the base_address_modifier field of an IPMI entry. */
96 #define	IPMI_BAM_IRQ_TRIGGER	0x01
97 #define	IPMI_BAM_IRQ_POLARITY	0x02
98 #define	IPMI_BAM_IRQ_VALID	0x08
99 #define	IPMI_BAM_ADDR_LSB(bam)	(((bam) & 0x10) >> 4)
100 #define	IPMI_BAM_REG_SPACING(bam) (((bam) & 0xc0) >> 6)
101 #define	SPACING_8		0x0
102 #define	SPACING_32		0x1
103 #define	SPACING_16		0x2
104 
105 #define	SMBIOS_START		0xf0000
106 #define	SMBIOS_STEP		0x10
107 #define	SMBIOS_OFF		0
108 #define	SMBIOS_LEN		4
109 #define	SMBIOS_SIG		"_SM_"
110 
111 typedef void (*dispatchproc_t)(uint8_t *p, char **table,
112     struct ipmi_get_info *info);
113 
114 static struct ipmi_get_info ipmi_info;
115 static int ipmi_probed;
116 static struct mtx ipmi_info_mtx;
117 MTX_SYSINIT(ipmi_info, &ipmi_info_mtx, "ipmi info", MTX_DEF);
118 
119 static char	*get_strings(char *, char **);
120 static void	ipmi_smbios_probe(struct ipmi_get_info *);
121 static int	smbios_cksum	(struct smbios_table_entry *);
122 static void	smbios_run_table(uint8_t *, int, dispatchproc_t *,
123 		    struct ipmi_get_info *);
124 static void	smbios_t38_proc_info(uint8_t *, char **,
125 		    struct ipmi_get_info *);
126 
127 static void
128 smbios_t38_proc_info(uint8_t *p, char **table, struct ipmi_get_info *info)
129 {
130 	struct ipmi_entry *s = (struct ipmi_entry *)p;
131 
132 	bzero(info, sizeof(struct ipmi_get_info));
133 	switch (s->interface_type) {
134 	case KCS_MODE:
135 	case SMIC_MODE:
136 		info->address = IPMI_BAR_ADDR(s->base_address) |
137 		    IPMI_BAM_ADDR_LSB(s->base_address_modifier);
138 		info->io_mode = IPMI_BAR_MODE(s->base_address);
139 		switch (IPMI_BAM_REG_SPACING(s->base_address_modifier)) {
140 		case SPACING_8:
141 			info->offset = 1;
142 			break;
143 		case SPACING_32:
144 			info->offset = 4;
145 			break;
146 		case SPACING_16:
147 			info->offset = 2;
148 			break;
149 		default:
150 			printf("SMBIOS: Invalid register spacing\n");
151 			return;
152 		}
153 		break;
154 	case SSIF_MODE:
155 		if ((s->base_address & 0xffffffffffffff00) != 0) {
156 			printf("SMBIOS: Invalid SSIF SMBus address, using BMC I2C slave address instead\n");
157 			info->address = s->i2c_slave_address >> 1;
158 			break;
159 		}
160 		info->address = IPMI_BAR_ADDR(s->base_address) >> 1;
161 		break;
162 	default:
163 		return;
164 	}
165 	if (s->length > offsetof(struct ipmi_entry, interrupt_number)) {
166 		if (s->interrupt_number > 15)
167 			printf("SMBIOS: Non-ISA IRQ %d for IPMI\n",
168 			    s->interrupt_number);
169 		else
170 			info->irq = s->interrupt_number;
171 	}
172 	info->iface_type = s->interface_type;
173 }
174 
175 static char *
176 get_strings(char *p, char **table)
177 {
178 	/* Scan for strings, stoping at a single null byte */
179 	while (*p != 0) {
180 		*table++ = p;
181 		p += strlen(p) + 1;
182 	}
183 	*table = 0;
184 
185 	/* Skip past terminating null byte */
186 	return (p + 1);
187 }
188 
189 
190 static void
191 smbios_run_table(uint8_t *p, int entries, dispatchproc_t *dispatchstatus,
192     struct ipmi_get_info *info)
193 {
194 	struct structure_header *s;
195 	char *table[20];
196 	uint8_t *nextp;
197 
198 	while(entries--) {
199 		s = (struct structure_header *) p;
200 		nextp = get_strings(p + s->length, table);
201 
202 		/*
203 		 * No strings still has a double-null at the end,
204 		 * skip over it
205 		 */
206 		if (table[0] == 0)
207 			nextp++;
208 
209 		if (dispatchstatus[*p]) {
210 			(dispatchstatus[*p])(p, table, info);
211 		}
212 		p = nextp;
213 	}
214 }
215 
216 /*
217  * Walk the SMBIOS table looking for an IPMI (type 38) entry.  If we find
218  * one, return the parsed data in the passed in ipmi_get_info structure and
219  * return true.  If we don't find one, return false.
220  */
221 static void
222 ipmi_smbios_probe(struct ipmi_get_info *info)
223 {
224 	dispatchproc_t dispatch_smbios_ipmi[256];
225 	struct smbios_table_entry *header;
226 	void *table;
227 	u_int32_t addr;
228 
229 	bzero(info, sizeof(struct ipmi_get_info));
230 
231 	/* Find the SMBIOS table header. */
232 	addr = bios_sigsearch(SMBIOS_START, SMBIOS_SIG, SMBIOS_LEN,
233 			      SMBIOS_STEP, SMBIOS_OFF);
234 	if (addr == 0)
235 		return;
236 
237 	/*
238 	 * Map the header.  We first map a fixed size to get the actual
239 	 * length and then map it a second time with the actual length so
240 	 * we can verify the checksum.
241 	 */
242 	header = pmap_mapbios(addr, sizeof(struct smbios_table_entry));
243 	table = pmap_mapbios(addr, header->length);
244 	pmap_unmapbios((vm_offset_t)header, sizeof(struct smbios_table_entry));
245 	header = table;
246 	if (smbios_cksum(header) != 0) {
247 		pmap_unmapbios((vm_offset_t)header, header->length);
248 		return;
249 	}
250 
251 	/* Now map the actual table and walk it looking for an IPMI entry. */
252 	table = pmap_mapbios(header->structure_table_address,
253 	    header->structure_table_length);
254 	bzero((void *)dispatch_smbios_ipmi, sizeof(dispatch_smbios_ipmi));
255 	dispatch_smbios_ipmi[38] = (void *)smbios_t38_proc_info;
256 	smbios_run_table(table, header->number_structures, dispatch_smbios_ipmi,
257 	    info);
258 
259 	/* Unmap everything. */
260 	pmap_unmapbios((vm_offset_t)table, header->structure_table_length);
261 	pmap_unmapbios((vm_offset_t)header, header->length);
262 }
263 
264 /*
265  * Return the SMBIOS IPMI table entry info to the caller.  If we haven't
266  * searched the IPMI table yet, search it.  Otherwise, return a cached
267  * copy of the data.
268  */
269 int
270 ipmi_smbios_identify(struct ipmi_get_info *info)
271 {
272 
273 	mtx_lock(&ipmi_info_mtx);
274 	switch (ipmi_probed) {
275 	case 0:
276 		/* Need to probe the SMBIOS table. */
277 		ipmi_probed++;
278 		mtx_unlock(&ipmi_info_mtx);
279 		ipmi_smbios_probe(&ipmi_info);
280 		mtx_lock(&ipmi_info_mtx);
281 		ipmi_probed++;
282 		wakeup(&ipmi_info);
283 		break;
284 	case 1:
285 		/* Another thread is currently probing the table, so wait. */
286 		while (ipmi_probed == 1)
287 			msleep(&ipmi_info, &ipmi_info_mtx, 0, "ipmi info", 0);
288 		break;
289 	default:
290 		/* The cached data is available. */
291 		break;
292 	}
293 
294 	bcopy(&ipmi_info, info, sizeof(ipmi_info));
295 	mtx_unlock(&ipmi_info_mtx);
296 
297 	return (info->iface_type != 0);
298 }
299 
300 static int
301 smbios_cksum (struct smbios_table_entry *e)
302 {
303 	u_int8_t *ptr;
304 	u_int8_t cksum;
305 	int i;
306 
307 	ptr = (u_int8_t *)e;
308 	cksum = 0;
309 	for (i = 0; i < e->length; i++) {
310 		cksum += ptr[i];
311 	}
312 
313 	return (cksum);
314 }
315