xref: /freebsd/sys/dev/ipmi/ipmi_smbios.c (revision 258a0d760aa8b42899a000e30f610f900a402556)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2006 IronPort Systems Inc. <ambrisko@ironport.com>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/bus.h>
35 #include <sys/condvar.h>
36 #include <sys/eventhandler.h>
37 #include <sys/kernel.h>
38 #include <sys/selinfo.h>
39 #include <sys/efi.h>
40 
41 #include <vm/vm.h>
42 #include <vm/pmap.h>
43 #if defined(__amd64__) || defined(__i386__)
44 #include <machine/pc/bios.h>
45 #endif
46 #include <dev/smbios/smbios.h>
47 
48 #ifdef LOCAL_MODULE
49 #include <ipmi.h>
50 #include <ipmivars.h>
51 #else
52 #include <sys/ipmi.h>
53 #include <dev/ipmi/ipmivars.h>
54 #endif
55 
56 struct ipmi_entry {
57 	uint8_t		type;
58 	uint8_t		length;
59 	uint16_t	handle;
60 	uint8_t		interface_type;
61 	uint8_t		spec_revision;
62 	uint8_t		i2c_slave_address;
63 	uint8_t		NV_storage_device_address;
64 	uint64_t	base_address;
65 	uint8_t		base_address_modifier;
66 	uint8_t		interrupt_number;
67 };
68 
69 /* Fields in the base_address field of an IPMI entry. */
70 #define	IPMI_BAR_MODE(ba)	((ba) & 0x0000000000000001)
71 #define	IPMI_BAR_ADDR(ba)	((ba) & 0xfffffffffffffffe)
72 
73 /* Fields in the base_address_modifier field of an IPMI entry. */
74 #define	IPMI_BAM_IRQ_TRIGGER	0x01
75 #define	IPMI_BAM_IRQ_POLARITY	0x02
76 #define	IPMI_BAM_IRQ_VALID	0x08
77 #define	IPMI_BAM_ADDR_LSB(bam)	(((bam) & 0x10) >> 4)
78 #define	IPMI_BAM_REG_SPACING(bam) (((bam) & 0xc0) >> 6)
79 #define	SPACING_8		0x0
80 #define	SPACING_32		0x1
81 #define	SPACING_16		0x2
82 
83 static struct ipmi_get_info ipmi_info;
84 static int ipmi_probed;
85 static struct mtx ipmi_info_mtx;
86 MTX_SYSINIT(ipmi_info, &ipmi_info_mtx, "ipmi info", MTX_DEF);
87 
88 static void	ipmi_smbios_probe(struct ipmi_get_info *);
89 static int	smbios_cksum(struct smbios_eps *);
90 static void	smbios_ipmi_info(struct smbios_structure_header *, void *);
91 
92 static void
93 smbios_ipmi_info(struct smbios_structure_header *h, void *arg)
94 {
95 	struct ipmi_get_info *info;
96 	struct ipmi_entry *s;
97 
98 	if (h->type != 38 || h->length <
99 	    offsetof(struct ipmi_entry, interrupt_number))
100 		return;
101 	s = (struct ipmi_entry *)h;
102 	info = arg;
103 	bzero(info, sizeof(struct ipmi_get_info));
104 	switch (s->interface_type) {
105 	case KCS_MODE:
106 	case SMIC_MODE:
107 	case BT_MODE:
108 		info->address = IPMI_BAR_ADDR(s->base_address) |
109 		    IPMI_BAM_ADDR_LSB(s->base_address_modifier);
110 		info->io_mode = IPMI_BAR_MODE(s->base_address);
111 		switch (IPMI_BAM_REG_SPACING(s->base_address_modifier)) {
112 		case SPACING_8:
113 			info->offset = 1;
114 			break;
115 		case SPACING_32:
116 			info->offset = 4;
117 			break;
118 		case SPACING_16:
119 			info->offset = 2;
120 			break;
121 		default:
122 			printf("SMBIOS: Invalid register spacing\n");
123 			return;
124 		}
125 		break;
126 	case SSIF_MODE:
127 		if ((s->base_address & 0xffffffffffffff00) != 0) {
128 			printf("SMBIOS: Invalid SSIF SMBus address, using BMC I2C slave address instead\n");
129 			info->address = s->i2c_slave_address;
130 			break;
131 		}
132 		info->address = IPMI_BAR_ADDR(s->base_address);
133 		break;
134 	default:
135 		return;
136 	}
137 	if (s->length > offsetof(struct ipmi_entry, interrupt_number)) {
138 		if (s->interrupt_number > 15)
139 			printf("SMBIOS: Non-ISA IRQ %d for IPMI\n",
140 			    s->interrupt_number);
141 		else
142 			info->irq = s->interrupt_number;
143 	}
144 	info->iface_type = s->interface_type;
145 }
146 
147 /*
148  * Walk the SMBIOS table looking for an IPMI (type 38) entry.  If we find
149  * one, return the parsed data in the passed in ipmi_get_info structure and
150  * return true.  If we don't find one, return false.
151  */
152 static void
153 ipmi_smbios_probe(struct ipmi_get_info *info)
154 {
155 #ifdef ARCH_MAY_USE_EFI
156 	struct uuid efi_smbios;
157 	void *addr_efi;
158 #endif
159 	struct smbios_eps *header;
160 	void *table;
161 	u_int32_t addr;
162 
163 	addr = 0;
164 	bzero(info, sizeof(struct ipmi_get_info));
165 
166 #ifdef ARCH_MAY_USE_EFI
167 	efi_smbios = (struct uuid)EFI_TABLE_SMBIOS;
168 	if (!efi_get_table(&efi_smbios, &addr_efi))
169 		addr = (vm_paddr_t)addr_efi;
170 #endif
171 
172 	if (addr == 0)
173 		/* Find the SMBIOS table header. */
174 		addr = bios_sigsearch(SMBIOS_START, SMBIOS_SIG, SMBIOS_LEN,
175 			SMBIOS_STEP, SMBIOS_OFF);
176 	if (addr == 0)
177 		return;
178 
179 	/*
180 	 * Map the header.  We first map a fixed size to get the actual
181 	 * length and then map it a second time with the actual length so
182 	 * we can verify the checksum.
183 	 */
184 	header = pmap_mapbios(addr, sizeof(struct smbios_eps));
185 	table = pmap_mapbios(addr, header->length);
186 	pmap_unmapbios(header, sizeof(struct smbios_eps));
187 	header = table;
188 	if (smbios_cksum(header) != 0) {
189 		pmap_unmapbios(header, header->length);
190 		return;
191 	}
192 
193 	/* Now map the actual table and walk it looking for an IPMI entry. */
194 	table = pmap_mapbios(header->structure_table_address,
195 	    header->structure_table_length);
196 	smbios_walk_table(table, header->number_structures, smbios_ipmi_info,
197 	    info);
198 
199 	/* Unmap everything. */
200 	pmap_unmapbios(table, header->structure_table_length);
201 	pmap_unmapbios(header, header->length);
202 }
203 
204 /*
205  * Return the SMBIOS IPMI table entry info to the caller.  If we haven't
206  * searched the IPMI table yet, search it.  Otherwise, return a cached
207  * copy of the data.
208  */
209 int
210 ipmi_smbios_identify(struct ipmi_get_info *info)
211 {
212 
213 	mtx_lock(&ipmi_info_mtx);
214 	switch (ipmi_probed) {
215 	case 0:
216 		/* Need to probe the SMBIOS table. */
217 		ipmi_probed++;
218 		mtx_unlock(&ipmi_info_mtx);
219 		ipmi_smbios_probe(&ipmi_info);
220 		mtx_lock(&ipmi_info_mtx);
221 		ipmi_probed++;
222 		wakeup(&ipmi_info);
223 		break;
224 	case 1:
225 		/* Another thread is currently probing the table, so wait. */
226 		while (ipmi_probed == 1)
227 			msleep(&ipmi_info, &ipmi_info_mtx, 0, "ipmi info", 0);
228 		break;
229 	default:
230 		/* The cached data is available. */
231 		break;
232 	}
233 
234 	bcopy(&ipmi_info, info, sizeof(ipmi_info));
235 	mtx_unlock(&ipmi_info_mtx);
236 
237 	return (info->iface_type != 0);
238 }
239 
240 static int
241 smbios_cksum(struct smbios_eps *e)
242 {
243 	u_int8_t *ptr;
244 	u_int8_t cksum;
245 	int i;
246 
247 	ptr = (u_int8_t *)e;
248 	cksum = 0;
249 	for (i = 0; i < e->length; i++) {
250 		cksum += ptr[i];
251 	}
252 
253 	return (cksum);
254 }
255