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
50struct ipmi_entry {
51	uint8_t		type;
52	uint8_t		length;
53	uint16_t	handle;
54	uint8_t		interface_type;
55	uint8_t		spec_revision;
56	uint8_t		i2c_slave_address;
57	uint8_t		NV_storage_device_address;
58	uint64_t	base_address;
59	uint8_t		base_address_modifier;
60	uint8_t		interrupt_number;
61};
62
63/* Fields in the base_address field of an IPMI entry. */
64#define	IPMI_BAR_MODE(ba)	((ba) & 0x0000000000000001)
65#define	IPMI_BAR_ADDR(ba)	((ba) & 0xfffffffffffffffe)
66
67/* Fields in the base_address_modifier field of an IPMI entry. */
68#define	IPMI_BAM_IRQ_TRIGGER	0x01
69#define	IPMI_BAM_IRQ_POLARITY	0x02
70#define	IPMI_BAM_IRQ_VALID	0x08
71#define	IPMI_BAM_ADDR_LSB(bam)	(((bam) & 0x10) >> 4)
72#define	IPMI_BAM_REG_SPACING(bam) (((bam) & 0xc0) >> 6)
73#define	SPACING_8		0x0
74#define	SPACING_32		0x1
75#define	SPACING_16		0x2
76
77typedef void (*smbios_callback_t)(struct smbios_structure_header *, void *);
78
79static struct ipmi_get_info ipmi_info;
80static int ipmi_probed;
81static struct mtx ipmi_info_mtx;
82MTX_SYSINIT(ipmi_info, &ipmi_info_mtx, "ipmi info", MTX_DEF);
83
84static void	ipmi_smbios_probe(struct ipmi_get_info *);
85static int	smbios_cksum(struct smbios_eps *);
86static void	smbios_walk_table(uint8_t *, int, smbios_callback_t,
87		    void *);
88static void	smbios_ipmi_info(struct smbios_structure_header *, void *);
89
90static void
91smbios_ipmi_info(struct smbios_structure_header *h, void *arg)
92{
93	struct ipmi_get_info *info;
94	struct ipmi_entry *s;
95
96	if (h->type != 38 || h->length <
97	    offsetof(struct ipmi_entry, interrupt_number))
98		return;
99	s = (struct ipmi_entry *)h;
100	info = arg;
101	bzero(info, sizeof(struct ipmi_get_info));
102	switch (s->interface_type) {
103	case KCS_MODE:
104	case SMIC_MODE:
105		info->address = IPMI_BAR_ADDR(s->base_address) |
106		    IPMI_BAM_ADDR_LSB(s->base_address_modifier);
107		info->io_mode = IPMI_BAR_MODE(s->base_address);
108		switch (IPMI_BAM_REG_SPACING(s->base_address_modifier)) {
109		case SPACING_8:
110			info->offset = 1;
111			break;
112		case SPACING_32:
113			info->offset = 4;
114			break;
115		case SPACING_16:
116			info->offset = 2;
117			break;
118		default:
119			printf("SMBIOS: Invalid register spacing\n");
120			return;
121		}
122		break;
123	case SSIF_MODE:
124		if ((s->base_address & 0xffffffffffffff00) != 0) {
125			printf("SMBIOS: Invalid SSIF SMBus address, using BMC I2C slave address instead\n");
126			info->address = s->i2c_slave_address;
127			break;
128		}
129		info->address = IPMI_BAR_ADDR(s->base_address);
130		break;
131	default:
132		return;
133	}
134	if (s->length > offsetof(struct ipmi_entry, interrupt_number)) {
135		if (s->interrupt_number > 15)
136			printf("SMBIOS: Non-ISA IRQ %d for IPMI\n",
137			    s->interrupt_number);
138		else
139			info->irq = s->interrupt_number;
140	}
141	info->iface_type = s->interface_type;
142}
143
144static void
145smbios_walk_table(uint8_t *p, int entries, smbios_callback_t cb, void *arg)
146{
147	struct smbios_structure_header *s;
148
149	while (entries--) {
150		s = (struct smbios_structure_header *)p;
151		cb(s, arg);
152
153		/*
154		 * Look for a double-nul after the end of the
155		 * formatted area of this structure.
156		 */
157		p += s->length;
158		while (!(p[0] == 0 && p[1] == 0))
159			p++;
160
161		/*
162		 * Skip over the double-nul to the start of the next
163		 * structure.
164		 */
165		p += 2;
166	}
167}
168
169/*
170 * Walk the SMBIOS table looking for an IPMI (type 38) entry.  If we find
171 * one, return the parsed data in the passed in ipmi_get_info structure and
172 * return true.  If we don't find one, return false.
173 */
174static void
175ipmi_smbios_probe(struct ipmi_get_info *info)
176{
177	struct smbios_eps *header;
178	void *table;
179	u_int32_t addr;
180
181	bzero(info, sizeof(struct ipmi_get_info));
182
183	/* Find the SMBIOS table header. */
184	addr = bios_sigsearch(SMBIOS_START, SMBIOS_SIG, SMBIOS_LEN,
185			      SMBIOS_STEP, SMBIOS_OFF);
186	if (addr == 0)
187		return;
188
189	/*
190	 * Map the header.  We first map a fixed size to get the actual
191	 * length and then map it a second time with the actual length so
192	 * we can verify the checksum.
193	 */
194	header = pmap_mapbios(addr, sizeof(struct smbios_eps));
195	table = pmap_mapbios(addr, header->length);
196	pmap_unmapbios((vm_offset_t)header, sizeof(struct smbios_eps));
197	header = table;
198	if (smbios_cksum(header) != 0) {
199		pmap_unmapbios((vm_offset_t)header, header->length);
200		return;
201	}
202
203	/* Now map the actual table and walk it looking for an IPMI entry. */
204	table = pmap_mapbios(header->structure_table_address,
205	    header->structure_table_length);
206	smbios_walk_table(table, header->number_structures, smbios_ipmi_info,
207	    info);
208
209	/* Unmap everything. */
210	pmap_unmapbios((vm_offset_t)table, header->structure_table_length);
211	pmap_unmapbios((vm_offset_t)header, header->length);
212}
213
214/*
215 * Return the SMBIOS IPMI table entry info to the caller.  If we haven't
216 * searched the IPMI table yet, search it.  Otherwise, return a cached
217 * copy of the data.
218 */
219int
220ipmi_smbios_identify(struct ipmi_get_info *info)
221{
222
223	mtx_lock(&ipmi_info_mtx);
224	switch (ipmi_probed) {
225	case 0:
226		/* Need to probe the SMBIOS table. */
227		ipmi_probed++;
228		mtx_unlock(&ipmi_info_mtx);
229		ipmi_smbios_probe(&ipmi_info);
230		mtx_lock(&ipmi_info_mtx);
231		ipmi_probed++;
232		wakeup(&ipmi_info);
233		break;
234	case 1:
235		/* Another thread is currently probing the table, so wait. */
236		while (ipmi_probed == 1)
237			msleep(&ipmi_info, &ipmi_info_mtx, 0, "ipmi info", 0);
238		break;
239	default:
240		/* The cached data is available. */
241		break;
242	}
243
244	bcopy(&ipmi_info, info, sizeof(ipmi_info));
245	mtx_unlock(&ipmi_info_mtx);
246
247	return (info->iface_type != 0);
248}
249
250static int
251smbios_cksum(struct smbios_eps *e)
252{
253	u_int8_t *ptr;
254	u_int8_t cksum;
255	int i;
256
257	ptr = (u_int8_t *)e;
258	cksum = 0;
259	for (i = 0; i < e->length; i++) {
260		cksum += ptr[i];
261	}
262
263	return (cksum);
264}
265