1/*-
2 * Copyright (C) 2018 Justin Hibbits
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
17 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
18 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
19 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
20 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
21 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
22 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24
25#include <sys/param.h>
26#include <sys/kernel.h>
27#include <sys/systm.h>
28#include <sys/lock.h>
29#include <sys/module.h>
30#include <sys/mutex.h>
31#include <sys/bus.h>
32#include <sys/kthread.h>
33#include <sys/proc.h>
34#include <sys/selinfo.h>
35#include <sys/sysctl.h>
36
37#include <vm/vm.h>
38#include <vm/pmap.h>
39
40#include <machine/bus.h>
41
42#include <dev/ofw/openfirm.h>
43#include <dev/ofw/ofw_bus.h>
44#include <dev/ofw/ofw_bus_subr.h>
45
46#include <sys/ipmi.h>
47#include <dev/ipmi/ipmivars.h>
48
49#include <powerpc/powernv/opal.h>
50
51/*
52 * OPAL_IPMI_DEBUG
53 *
54 * 0 - disabled
55 * 1 - enable error messages (EPRINTF)
56 * 2 - enable error and debug messages (DPRINTF)
57 */
58#define	OPAL_IPMI_DEBUG		0
59#if OPAL_IPMI_DEBUG >= 2
60/* debug printf */
61#define	DPRINTF(fmt, ...)	printf("ipmi: " fmt "\n", ## __VA_ARGS__)
62#else
63#define	DPRINTF(fmt, ...)	((void)0)
64#endif
65#if OPAL_IPMI_DEBUG >= 1
66/* error printf: to print messages only when something fails */
67#define	EPRINTF(fmt, ...)	printf("ipmi: " fmt "\n", ## __VA_ARGS__)
68#else
69#define	EPRINTF(fmt, ...)	((void)0)
70#endif
71
72struct opal_ipmi_softc {
73	struct ipmi_softc ipmi;
74	uint64_t sc_interface;
75	int sc_timedout;
76	struct opal_ipmi_msg *sc_msg; /* Protected by IPMI lock */
77};
78
79static MALLOC_DEFINE(M_IPMI, "ipmi", "OPAL IPMI");
80
81static int
82opal_ipmi_recv(struct opal_ipmi_softc *sc, uint64_t *msg_len, int timo)
83{
84	int err;
85
86	if (timo == 0)
87		timo = MAX_TIMEOUT;
88	timo *= 10; /* Timeout is in milliseconds, we delay in 100us */
89
90	for (;;) {
91		*msg_len = sizeof(struct opal_ipmi_msg) + IPMI_MAX_RX;
92		/* Crank the OPAL state machine while we poll for a reply. */
93		opal_call(OPAL_POLL_EVENTS, NULL);
94		err = opal_call(OPAL_IPMI_RECV, sc->sc_interface,
95		    vtophys(sc->sc_msg), vtophys(msg_len));
96		if (err != OPAL_EMPTY)
97			break;
98
99		DELAY(100);
100		if (timo-- <= 0) {
101			sc->sc_timedout = 1;
102			break;
103		}
104	}
105
106	if (err != OPAL_SUCCESS)
107		EPRINTF("RECV: error: %d", err);
108
109	switch (err) {
110	case OPAL_SUCCESS:
111		DPRINTF("RECV: rv=%02x len=%ld",
112		    sc->sc_msg->data[0], *msg_len);
113		return (0);
114	case OPAL_RESOURCE:
115		return (ENOMEM);
116	case OPAL_EMPTY:
117		return (EAGAIN);
118	default:
119		return (EIO);
120	}
121}
122
123static void
124opal_ipmi_discard_msgs(struct opal_ipmi_softc *sc)
125{
126	uint64_t msg_len;
127	int err, i = 0;
128
129	/* OPAL_IPMI_RECV fails when msg version is not set. */
130	sc->sc_msg->version = OPAL_IPMI_MSG_FORMAT_VERSION_1;
131
132	/* Wait up to 100ms for the 1st timedout message. */
133	err = opal_ipmi_recv(sc, &msg_len, 100);
134	while (err == 0) {
135		i++;
136		/* Wait only 10ms for the remaining messages. */
137		err = opal_ipmi_recv(sc, &msg_len, 10);
138	}
139	if (i > 0)
140		EPRINTF("Discarded %d message(s)", i);
141	sc->sc_timedout = 0;
142}
143
144static int
145opal_ipmi_polled_request(struct opal_ipmi_softc *sc, struct ipmi_request *req,
146    int timo)
147{
148	uint64_t msg_len;
149	int err;
150
151	/*
152	 * Discard timed out messages before sending a new one, to avoid
153	 * them being confused with the reply of the new message.
154	 */
155	if (sc->sc_timedout)
156		opal_ipmi_discard_msgs(sc);
157
158	/* Construct and send the message. */
159	sc->sc_msg->version = OPAL_IPMI_MSG_FORMAT_VERSION_1;
160	sc->sc_msg->netfn = req->ir_addr;
161	sc->sc_msg->cmd = req->ir_command;
162
163	if (req->ir_requestlen > IPMI_MAX_RX) {
164		err = ENOMEM;
165		goto out;
166	}
167	memcpy(sc->sc_msg->data, req->ir_request, req->ir_requestlen);
168
169	msg_len = sizeof(*sc->sc_msg) + req->ir_requestlen;
170	err = opal_call(OPAL_IPMI_SEND, sc->sc_interface, vtophys(sc->sc_msg),
171	    msg_len);
172
173	DPRINTF("SEND: cmd=%02x netfn=%02x len=%ld -> %d",
174	    sc->sc_msg->cmd, sc->sc_msg->netfn, msg_len, err);
175
176	if (err != OPAL_SUCCESS)
177		EPRINTF("SEND: error: %d", err);
178
179	switch (err) {
180	case OPAL_SUCCESS:
181		break;
182	case OPAL_PARAMETER:
183	case OPAL_UNSUPPORTED:
184		err = EINVAL;
185		goto out;
186	case OPAL_RESOURCE:
187		err = ENOMEM;
188		goto out;
189	case OPAL_HARDWARE:
190	default:
191		err = EIO;
192		goto out;
193	}
194
195	if ((err = opal_ipmi_recv(sc, &msg_len, timo)) == 0) {
196		/* Subtract one extra for the completion code. */
197		req->ir_replylen = msg_len - sizeof(struct opal_ipmi_msg) - 1;
198		req->ir_replylen = min(req->ir_replylen, req->ir_replybuflen);
199		memcpy(req->ir_reply, &sc->sc_msg->data[1], req->ir_replylen);
200		req->ir_compcode = sc->sc_msg->data[0];
201	}
202
203out:
204	return (err);
205}
206
207static int
208opal_ipmi_probe(device_t dev)
209{
210	if (!ofw_bus_is_compatible(dev, "ibm,opal-ipmi"))
211		return (ENXIO);
212
213	device_set_desc(dev, "OPAL IPMI System Interface");
214
215	return (BUS_PROBE_DEFAULT);
216}
217
218static void
219opal_ipmi_loop(void *arg)
220{
221	struct opal_ipmi_softc *sc = arg;
222	struct ipmi_request *req;
223	int i, err;
224
225	IPMI_LOCK(&sc->ipmi);
226	while ((req = ipmi_dequeue_request(&sc->ipmi)) != NULL) {
227		IPMI_UNLOCK(&sc->ipmi);
228		err = EIO;
229		for (i = 0; i < 3 && err != 0; i++) {
230			IPMI_IO_LOCK(&sc->ipmi);
231			err = opal_ipmi_polled_request(sc, req, MAX_TIMEOUT);
232			IPMI_IO_UNLOCK(&sc->ipmi);
233		}
234		req->ir_error = err == 0 ? 0 : EIO;
235		IPMI_LOCK(&sc->ipmi);
236		ipmi_complete_request(&sc->ipmi, req);
237	}
238	IPMI_UNLOCK(&sc->ipmi);
239	kproc_exit(0);
240}
241
242static int
243opal_ipmi_startup(struct ipmi_softc *sc)
244{
245
246	return (kproc_create(opal_ipmi_loop, sc, &sc->ipmi_kthread, 0, 0,
247	    "%s: opal", device_get_nameunit(sc->ipmi_dev)));
248}
249
250static int
251opal_ipmi_driver_request(struct ipmi_softc *isc, struct ipmi_request *req,
252    int timo)
253{
254	struct opal_ipmi_softc *sc = (struct opal_ipmi_softc *)isc;
255	int i, err;
256
257	for (i = 0; i < 3; i++) {
258		IPMI_LOCK(&sc->ipmi);
259		err = opal_ipmi_polled_request(sc, req, timo);
260		IPMI_UNLOCK(&sc->ipmi);
261		if (err == 0)
262			break;
263	}
264
265	req->ir_error = err;
266
267	return (err);
268}
269
270static int
271opal_ipmi_attach(device_t dev)
272{
273	struct opal_ipmi_softc *sc;
274	pcell_t ifid;
275
276	sc = device_get_softc(dev);
277
278	if (OF_getencprop(ofw_bus_get_node(dev), "ibm,ipmi-interface-id",
279	    &ifid, sizeof(ifid)) < 0) {
280		device_printf(dev, "Missing interface id\n");
281		return (ENXIO);
282	}
283	sc->sc_interface = ifid;
284	sc->ipmi.ipmi_startup = opal_ipmi_startup;
285	sc->ipmi.ipmi_driver_request = opal_ipmi_driver_request;
286	sc->ipmi.ipmi_enqueue_request = ipmi_polled_enqueue_request;
287	sc->ipmi.ipmi_driver_requests_polled = 1;
288	sc->ipmi.ipmi_dev = dev;
289
290	sc->sc_msg = malloc(sizeof(struct opal_ipmi_msg) + IPMI_MAX_RX, M_IPMI,
291	    M_WAITOK | M_ZERO);
292
293	/* Discard old messages that may have remained in receive queue. */
294	opal_ipmi_discard_msgs(sc);
295
296	return (ipmi_attach(dev));
297}
298
299static int
300opal_ipmi_detach(device_t dev)
301{
302	struct opal_ipmi_softc *sc;
303	int err;
304
305	sc = device_get_softc(dev);
306	err = ipmi_detach(dev);
307	if (err == 0)
308		free(sc->sc_msg, M_IPMI);
309
310	return (err);
311}
312
313static device_method_t	opal_ipmi_methods[] = {
314	/* Device interface */
315	DEVMETHOD(device_probe,		opal_ipmi_probe),
316	DEVMETHOD(device_attach,	opal_ipmi_attach),
317	DEVMETHOD(device_detach,	opal_ipmi_detach),
318	DEVMETHOD_END
319};
320
321static driver_t opal_ipmi_driver = {
322	"ipmi",
323	opal_ipmi_methods,
324	sizeof(struct opal_ipmi_softc)
325};
326
327DRIVER_MODULE(opal_ipmi, opal, opal_ipmi_driver, NULL, NULL);
328