xref: /freebsd/sys/dev/ipmi/ipmi_bt.c (revision 6137b5f7b8c183ee8806d79b3f1d8e5e3ddb3df3)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2023 Yandex LLC
5  * Copyright (c) 2023 Andrey V. Elsukov <ae@FreeBSD.org>
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/param.h>
30 #include <sys/systm.h>
31 #include <sys/bus.h>
32 #include <sys/condvar.h>
33 #include <sys/eventhandler.h>
34 #include <sys/kernel.h>
35 #include <sys/kthread.h>
36 #include <sys/module.h>
37 #include <sys/rman.h>
38 #include <sys/selinfo.h>
39 #include <machine/bus.h>
40 
41 #include <sys/ipmi.h>
42 #include <dev/ipmi/ipmivars.h>
43 
44 /*
45  * BT interface
46  */
47 
48 #define	DMSG0(sc, fmt, ...)	do {				\
49 	device_printf((sc)->ipmi_dev, "BT: %s: " fmt "\n",	\
50 	    __func__, ## __VA_ARGS__);				\
51 } while (0)
52 
53 #define	DMSGV(...)		if (bootverbose) {		\
54 	DMSG0(__VA_ARGS__);					\
55 }
56 
57 #ifdef IPMI_BT_DEBUG
58 #define	DMSG(...)		DMSG0(__VA_ARGS__)
59 #else
60 #define	DMSG(...)
61 #endif
62 
63 #define	BT_IO_BASE		0xe4
64 
65 #define	BT_CTRL_REG		0
66 #define	  BT_C_CLR_WR_PTR	(1L << 0)
67 #define	  BT_C_CLR_RD_PTR	(1L << 1)
68 #define	  BT_C_H2B_ATN		(1L << 2)
69 #define	  BT_C_B2H_ATN		(1L << 3)
70 #define	  BT_C_SMS_ATN		(1L << 4)
71 #define	  BT_C_OEM0		(1L << 5)
72 #define	  BT_C_H_BUSY		(1L << 6)
73 #define	  BT_C_B_BUSY		(1L << 7)
74 
75 #define	BT_CTRL_BITS		"\20\01CLR_WR_PTR\02CLR_RD_PTR\03H2B_ATN\04B2H_ATN"\
76 				"\05SMS_ATN\06OEM0\07H_BUSY\010B_BUSY"
77 
78 #define	BT_DATA_REG		1
79 #define	 BTMSG_REQLEN		3
80 #define	 BTMSG_REPLEN		4
81 
82 #define	BT_INTMASK_REG		2
83 #define	 BT_IM_B2H_IRQ_EN	(1L << 0)
84 #define	 BT_IM_B2H_IRQ		(1L << 1)
85 #define	 BT_IM_BMC_HWRST	(1L << 7)
86 
87 static int bt_polled_request(struct ipmi_softc *, struct ipmi_request *);
88 static int bt_driver_request(struct ipmi_softc *, struct ipmi_request *, int);
89 static int bt_wait(struct ipmi_softc *, uint8_t, uint8_t);
90 static int bt_reset(struct ipmi_softc *);
91 
92 static void bt_loop(void *);
93 static int bt_startup(struct ipmi_softc *);
94 
95 #define	BT_DELAY_MIN	1
96 #define	BT_DELAY_MAX	256
97 
98 static int
99 bt_wait(struct ipmi_softc *sc, uint8_t mask, uint8_t wanted)
100 {
101 	volatile uint8_t value;
102 	int delay = BT_DELAY_MIN;
103 	int count = 20000; /* about 5 seconds */
104 
105 	while (count--) {
106 		value = INB(sc, BT_CTRL_REG);
107 		if ((value & mask) == wanted)
108 			return (value);
109 		/*
110 		 * The wait delay is increased exponentially to avoid putting
111 		 * significant load on I/O bus.
112 		 */
113 		DELAY(delay);
114 		if (delay < BT_DELAY_MAX)
115 			delay <<= 1;
116 	}
117 	DMSGV(sc, "failed: m=%b w=%b v=0x%02x\n",
118 	    mask, BT_CTRL_BITS, wanted, BT_CTRL_BITS, value);
119 	return (-1);
120 
121 }
122 
123 static int
124 bt_reset(struct ipmi_softc *sc)
125 {
126 	uint8_t v;
127 
128 	v = INB(sc, BT_CTRL_REG);
129 	DMSG(sc, "ctrl: %b", v, BT_CTRL_BITS);
130 	v &= BT_C_H_BUSY; /* clear H_BUSY iff it set */
131 	v |= BT_C_CLR_WR_PTR | BT_C_CLR_RD_PTR | BT_C_B2H_ATN | BT_C_H2B_ATN;
132 
133 	bt_wait(sc, BT_C_B_BUSY, 0);
134 	OUTB(sc, BT_CTRL_REG, v);
135 
136 	v = BT_IM_B2H_IRQ | BT_IM_BMC_HWRST;
137 	OUTB(sc, BT_INTMASK_REG, v);
138 
139 	return (0);
140 }
141 
142 /*
143  * Send a request message and collect the reply. Returns 1 if we
144  * succeed.
145  */
146 static int
147 bt_polled_request(struct ipmi_softc *sc, struct ipmi_request *req)
148 {
149 	uint8_t addr, cmd, seq, v;
150 	int i;
151 
152 	IPMI_IO_LOCK(sc);
153 
154 	/*
155 	 * Send the request:
156 	 *
157 	 * Byte 1 | Byte 2    | Byte 3 | Byte 4 | Byte 5:N
158 	 * -------+-----------+--------+--------+---------
159 	 * Length | NetFn/LUN | Seq    | Cmd    | Data
160 	 */
161 
162 	if (bt_wait(sc, BT_C_B_BUSY | BT_C_H2B_ATN, 0) < 0) {
163 		DMSG(sc, "failed to start write transfer");
164 		goto fail;
165 	}
166 	DMSG(sc, "request: length=%d, addr=0x%02x, seq=%u, cmd=0x%02x",
167 	    (int)req->ir_requestlen, req->ir_addr, sc->ipmi_bt_seq, req->ir_command);
168 	OUTB(sc, BT_CTRL_REG, BT_C_CLR_WR_PTR);
169 	OUTB(sc, BT_DATA_REG, req->ir_requestlen + BTMSG_REQLEN);
170 	OUTB(sc, BT_DATA_REG, req->ir_addr);
171 	OUTB(sc, BT_DATA_REG, sc->ipmi_bt_seq);
172 	OUTB(sc, BT_DATA_REG, req->ir_command);
173 	for (i = 0; i < req->ir_requestlen; i++)
174 		OUTB(sc, BT_DATA_REG, req->ir_request[i]);
175 	OUTB(sc, BT_CTRL_REG, BT_C_H2B_ATN);
176 
177 	if (bt_wait(sc, BT_C_B_BUSY | BT_C_H2B_ATN, 0) < 0) {
178 		DMSG(sc, "failed to finish write transfer");
179 		goto fail;
180 	}
181 
182 	/*
183 	 * Read the reply:
184 	 *
185 	 * Byte 1 | Byte 2    | Byte 3 | Byte 4 | Byte 5          | Byte 6:N
186 	 * -------+-----------+--------+--------+-----------------+---------
187 	 * Length | NetFn/LUN | Seq    | Cmd    | Completion code | Data
188 	 */
189 	if (bt_wait(sc, BT_C_B2H_ATN, BT_C_B2H_ATN) < 0) {
190 		DMSG(sc, "got no reply from BMC");
191 		goto fail;
192 	}
193 	OUTB(sc, BT_CTRL_REG, BT_C_H_BUSY);
194 	OUTB(sc, BT_CTRL_REG, BT_C_B2H_ATN);
195 	OUTB(sc, BT_CTRL_REG, BT_C_CLR_RD_PTR);
196 
197 	i = INB(sc, BT_DATA_REG);
198 	if (i < BTMSG_REPLEN) {
199 		DMSG(sc, "wrong data length: %d", i);
200 		goto fail;
201 	}
202 	req->ir_replylen = i - BTMSG_REPLEN;
203 	DMSG(sc, "data length: %d, frame length: %d", req->ir_replylen, i);
204 
205 	addr = INB(sc, BT_DATA_REG);
206 	if (addr != IPMI_REPLY_ADDR(req->ir_addr)) {
207 		DMSGV(sc, "address doesn't match: addr=0x%02x vs. 0x%02x",
208 		    req->ir_addr, addr);
209 	}
210 
211 	seq = INB(sc, BT_DATA_REG);
212 	if (seq != sc->ipmi_bt_seq) {
213 		DMSGV(sc, "seq number doesn't match: seq=0x%02x vs. 0x%02x",
214 		    sc->ipmi_bt_seq, seq);
215 	}
216 
217 	cmd = INB(sc, BT_DATA_REG);
218 	if (cmd != req->ir_command) {
219 		DMSGV(sc, "command doesn't match: cmd=0x%02x vs. 0x%02x",
220 		    req->ir_command, cmd);
221 	}
222 
223 	req->ir_compcode = INB(sc, BT_DATA_REG);
224 	for (i = 0; i < req->ir_replylen; i++) {
225 		v = INB(sc, BT_DATA_REG);
226 		if (i < req->ir_replybuflen)
227 			req->ir_reply[i] = v;
228 	}
229 
230 	OUTB(sc, BT_CTRL_REG, BT_C_H_BUSY);
231 	IPMI_IO_UNLOCK(sc);
232 	DMSG(sc, "reply: length=%d, addr=0x%02x, seq=%u, cmd=0x%02x, code=0x%02x",
233 	    (int)req->ir_replylen, addr, seq, req->ir_command, req->ir_compcode);
234 	return (1);
235 fail:
236 	bt_reset(sc);
237 	IPMI_IO_UNLOCK(sc);
238 	return (0);
239 }
240 
241 static void
242 bt_loop(void *arg)
243 {
244 	struct ipmi_softc *sc = arg;
245 	struct ipmi_request *req;
246 
247 	IPMI_LOCK(sc);
248 	while ((req = ipmi_dequeue_request(sc)) != NULL) {
249 		IPMI_UNLOCK(sc);
250 		(void)bt_driver_request(sc, req, 0);
251 		IPMI_LOCK(sc);
252 		sc->ipmi_bt_seq++;
253 		ipmi_complete_request(sc, req);
254 	}
255 	IPMI_UNLOCK(sc);
256 	kproc_exit(0);
257 }
258 
259 static int
260 bt_startup(struct ipmi_softc *sc)
261 {
262 
263 	return (kproc_create(bt_loop, sc, &sc->ipmi_kthread, 0, 0, "%s: bt",
264 	    device_get_nameunit(sc->ipmi_dev)));
265 }
266 
267 static int
268 bt_driver_request(struct ipmi_softc *sc, struct ipmi_request *req, int timo __unused)
269 {
270 	int i, ok;
271 
272 	ok = 0;
273 	for (i = 0; i < 3 && !ok; i++)
274 		ok = bt_polled_request(sc, req);
275 	if (ok)
276 		req->ir_error = 0;
277 	else
278 		req->ir_error = EIO;
279 	return (req->ir_error);
280 }
281 
282 int
283 ipmi_bt_attach(struct ipmi_softc *sc)
284 {
285 	/* Setup function pointers. */
286 	sc->ipmi_startup = bt_startup;
287 	sc->ipmi_enqueue_request = ipmi_polled_enqueue_request;
288 	sc->ipmi_driver_request = bt_driver_request;
289 	sc->ipmi_driver_requests_polled = 1;
290 	sc->ipmi_bt_seq = 1;
291 
292 	return (bt_reset(sc));
293 }
294