xref: /freebsd/sys/dev/ipmi/ipmi_smbios.c (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
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 ipmi_entry {
56 	uint8_t		type;
57 	uint8_t		length;
58 	uint16_t	handle;
59 	uint8_t		interface_type;
60 	uint8_t		spec_revision;
61 	uint8_t		i2c_slave_address;
62 	uint8_t		NV_storage_device_address;
63 	uint64_t	base_address;
64 	uint8_t		base_address_modifier;
65 	uint8_t		interrupt_number;
66 };
67 
68 /* Fields in the base_address field of an IPMI entry. */
69 #define	IPMI_BAR_MODE(ba)	((ba) & 0x0000000000000001)
70 #define	IPMI_BAR_ADDR(ba)	((ba) & 0xfffffffffffffffe)
71 
72 /* Fields in the base_address_modifier field of an IPMI entry. */
73 #define	IPMI_BAM_IRQ_TRIGGER	0x01
74 #define	IPMI_BAM_IRQ_POLARITY	0x02
75 #define	IPMI_BAM_IRQ_VALID	0x08
76 #define	IPMI_BAM_ADDR_LSB(bam)	(((bam) & 0x10) >> 4)
77 #define	IPMI_BAM_REG_SPACING(bam) (((bam) & 0xc0) >> 6)
78 #define	SPACING_8		0x0
79 #define	SPACING_32		0x1
80 #define	SPACING_16		0x2
81 
82 typedef void (*smbios_callback_t)(struct smbios_structure_header *, void *);
83 
84 static struct ipmi_get_info ipmi_info;
85 static int ipmi_probed;
86 static struct mtx ipmi_info_mtx;
87 MTX_SYSINIT(ipmi_info, &ipmi_info_mtx, "ipmi info", MTX_DEF);
88 
89 static void	ipmi_smbios_probe(struct ipmi_get_info *);
90 static int	smbios_cksum(struct smbios_eps *);
91 static void	smbios_walk_table(uint8_t *, int, smbios_callback_t,
92 		    void *);
93 static void	smbios_ipmi_info(struct smbios_structure_header *, void *);
94 
95 static void
96 smbios_ipmi_info(struct smbios_structure_header *h, void *arg)
97 {
98 	struct ipmi_get_info *info;
99 	struct ipmi_entry *s;
100 
101 	if (h->type != 38 || h->length <
102 	    offsetof(struct ipmi_entry, interrupt_number))
103 		return;
104 	s = (struct ipmi_entry *)h;
105 	info = arg;
106 	bzero(info, sizeof(struct ipmi_get_info));
107 	switch (s->interface_type) {
108 	case KCS_MODE:
109 	case SMIC_MODE:
110 		info->address = IPMI_BAR_ADDR(s->base_address) |
111 		    IPMI_BAM_ADDR_LSB(s->base_address_modifier);
112 		info->io_mode = IPMI_BAR_MODE(s->base_address);
113 		switch (IPMI_BAM_REG_SPACING(s->base_address_modifier)) {
114 		case SPACING_8:
115 			info->offset = 1;
116 			break;
117 		case SPACING_32:
118 			info->offset = 4;
119 			break;
120 		case SPACING_16:
121 			info->offset = 2;
122 			break;
123 		default:
124 			printf("SMBIOS: Invalid register spacing\n");
125 			return;
126 		}
127 		break;
128 	case SSIF_MODE:
129 		if ((s->base_address & 0xffffffffffffff00) != 0) {
130 			printf("SMBIOS: Invalid SSIF SMBus address, using BMC I2C slave address instead\n");
131 			info->address = s->i2c_slave_address;
132 			break;
133 		}
134 		info->address = IPMI_BAR_ADDR(s->base_address);
135 		break;
136 	default:
137 		return;
138 	}
139 	if (s->length > offsetof(struct ipmi_entry, interrupt_number)) {
140 		if (s->interrupt_number > 15)
141 			printf("SMBIOS: Non-ISA IRQ %d for IPMI\n",
142 			    s->interrupt_number);
143 		else
144 			info->irq = s->interrupt_number;
145 	}
146 	info->iface_type = s->interface_type;
147 }
148 
149 static void
150 smbios_walk_table(uint8_t *p, int entries, smbios_callback_t cb, void *arg)
151 {
152 	struct smbios_structure_header *s;
153 
154 	while (entries--) {
155 		s = (struct smbios_structure_header *)p;
156 		cb(s, arg);
157 
158 		/*
159 		 * Look for a double-nul after the end of the
160 		 * formatted area of this structure.
161 		 */
162 		p += s->length;
163 		while (!(p[0] == 0 && p[1] == 0))
164 			p++;
165 
166 		/*
167 		 * Skip over the double-nul to the start of the next
168 		 * structure.
169 		 */
170 		p += 2;
171 	}
172 }
173 
174 /*
175  * Walk the SMBIOS table looking for an IPMI (type 38) entry.  If we find
176  * one, return the parsed data in the passed in ipmi_get_info structure and
177  * return true.  If we don't find one, return false.
178  */
179 static void
180 ipmi_smbios_probe(struct ipmi_get_info *info)
181 {
182 	struct smbios_eps *header;
183 	void *table;
184 	u_int32_t addr;
185 
186 	bzero(info, sizeof(struct ipmi_get_info));
187 
188 	/* Find the SMBIOS table header. */
189 	addr = bios_sigsearch(SMBIOS_START, SMBIOS_SIG, SMBIOS_LEN,
190 			      SMBIOS_STEP, SMBIOS_OFF);
191 	if (addr == 0)
192 		return;
193 
194 	/*
195 	 * Map the header.  We first map a fixed size to get the actual
196 	 * length and then map it a second time with the actual length so
197 	 * we can verify the checksum.
198 	 */
199 	header = pmap_mapbios(addr, sizeof(struct smbios_eps));
200 	table = pmap_mapbios(addr, header->length);
201 	pmap_unmapbios((vm_offset_t)header, sizeof(struct smbios_eps));
202 	header = table;
203 	if (smbios_cksum(header) != 0) {
204 		pmap_unmapbios((vm_offset_t)header, header->length);
205 		return;
206 	}
207 
208 	/* Now map the actual table and walk it looking for an IPMI entry. */
209 	table = pmap_mapbios(header->structure_table_address,
210 	    header->structure_table_length);
211 	smbios_walk_table(table, header->number_structures, smbios_ipmi_info,
212 	    info);
213 
214 	/* Unmap everything. */
215 	pmap_unmapbios((vm_offset_t)table, header->structure_table_length);
216 	pmap_unmapbios((vm_offset_t)header, header->length);
217 }
218 
219 /*
220  * Return the SMBIOS IPMI table entry info to the caller.  If we haven't
221  * searched the IPMI table yet, search it.  Otherwise, return a cached
222  * copy of the data.
223  */
224 int
225 ipmi_smbios_identify(struct ipmi_get_info *info)
226 {
227 
228 	mtx_lock(&ipmi_info_mtx);
229 	switch (ipmi_probed) {
230 	case 0:
231 		/* Need to probe the SMBIOS table. */
232 		ipmi_probed++;
233 		mtx_unlock(&ipmi_info_mtx);
234 		ipmi_smbios_probe(&ipmi_info);
235 		mtx_lock(&ipmi_info_mtx);
236 		ipmi_probed++;
237 		wakeup(&ipmi_info);
238 		break;
239 	case 1:
240 		/* Another thread is currently probing the table, so wait. */
241 		while (ipmi_probed == 1)
242 			msleep(&ipmi_info, &ipmi_info_mtx, 0, "ipmi info", 0);
243 		break;
244 	default:
245 		/* The cached data is available. */
246 		break;
247 	}
248 
249 	bcopy(&ipmi_info, info, sizeof(ipmi_info));
250 	mtx_unlock(&ipmi_info_mtx);
251 
252 	return (info->iface_type != 0);
253 }
254 
255 static int
256 smbios_cksum(struct smbios_eps *e)
257 {
258 	u_int8_t *ptr;
259 	u_int8_t cksum;
260 	int i;
261 
262 	ptr = (u_int8_t *)e;
263 	cksum = 0;
264 	for (i = 0; i < e->length; i++) {
265 		cksum += ptr[i];
266 	}
267 
268 	return (cksum);
269 }
270