Add an IPMI attachment for PowerNV systems

IPMI access on PowerNV systems is done through the OPAL firmware.  This adds a
simple attachment for communicating with the FSP/BMC on these machines.  This
has been tested on a Talos POWER9 workstation, only in the bootup phase, noting
the successful attachment messages:

...
ipmi0: IPMI device rev. 0, firmware rev. 2.00, version 2.0, device support mask 0
ipmi0: Number of channels 2
...

The ipmi device has not been added to GENERIC64, but may be after further
testing.  It may also eventually be added to the ipmi module at that point.

sys/conf/files.powerpc

@@ -42,6 +42,7 @@ dev/iicbus/ds1631.c		optional	ds1631 powermac
 dev/iicbus/ds1775.c		optional	ds1775 powermac
 dev/iicbus/max6690.c		optional	max6690 powermac
 dev/iicbus/ofw_iicbus.c		optional	iicbus aim
+dev/ipmi/ipmi.c			optional	ipmi
 dev/nand/nfc_fsl.c		optional	nand mpc85xx
 dev/nand/nfc_rb.c		optional	nand mpc85xx
 # Most ofw stuff below is brought in by conf/files for options FDT, but
@@ -188,6 +189,7 @@ powerpc/powernv/opal_console.c	optional	powernv
 powerpc/powernv/opal_dev.c	optional	powernv
 powerpc/powernv/opal_i2c.c	optional	iicbus fdt powernv
 powerpc/powernv/opal_i2cm.c	optional	iicbus fdt powernv
+powerpc/powernv/opal_ipmi.c	optional	powernv ipmi
 powerpc/powernv/opal_pci.c	optional	powernv pci
 powerpc/powernv/opal_sensor.c	optional	powernv
 powerpc/powernv/opalcall.S	optional	powernv

sys/powerpc/powernv/opal.h

@@ -73,6 +73,8 @@ int opal_call(uint64_t token, ...);
 #define	OPAL_REINIT_CPUS		70
 #define	OPAL_CHECK_ASYNC_COMPLETION	86
 #define	OPAL_SENSOR_READ		88
+#define	OPAL_IPMI_SEND			107
+#define	OPAL_IPMI_RECV			108
 #define	OPAL_I2C_REQUEST		109
 #define	OPAL_INT_GET_XIRR		122
 #define	OPAL_INT_SET_CPPR		123
@@ -106,8 +108,12 @@ int opal_call(uint64_t token, ...);
 #define	OPAL_PARAMETER			-1
 #define	OPAL_BUSY			-2
 #define	OPAL_CLOSED			-5
+#define	OPAL_HARDWARE			-6
+#define	OPAL_UNSUPPORTED		-7
+#define	OPAL_RESOURCE			-10
 #define	OPAL_BUSY_EVENT			-12
 #define	OPAL_ASYNC_COMPLETION		-15
+#define	OPAL_EMPTY			-16
 
 struct opal_msg {
 	uint32_t msg_type;
@@ -127,4 +133,13 @@ enum opal_msg_type {
 	OPAL_MSG_TYPE_MAX,
 };
 
+#define	OPAL_IPMI_MSG_FORMAT_VERSION_1	1
+
+struct opal_ipmi_msg {
+	uint8_t version;
+	uint8_t netfn;
+	uint8_t cmd;
+	uint8_t data[];
+};
+
 #endif

sys/powerpc/powernv/opal_ipmi.c

@@ -0,0 +1,241 @@
+/*-
+ * Copyright (C) 2018 Justin Hibbits
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/systm.h>
+#include <sys/module.h>
+#include <sys/types.h>
+#include <sys/bus.h>
+#include <sys/kthread.h>
+#include <sys/proc.h>
+#include <sys/selinfo.h>
+#include <sys/sysctl.h>
+
+#include <vm/vm.h>
+#include <vm/pmap.h>
+
+#include <machine/bus.h>
+
+#include <dev/ofw/openfirm.h>
+#include <dev/ofw/ofw_bus.h>
+#include <dev/ofw/ofw_bus_subr.h>
+
+#include <sys/ipmi.h>
+#include <dev/ipmi/ipmivars.h>
+
+#include "opal.h"
+
+struct opal_ipmi_softc {
+	struct ipmi_softc ipmi;
+	uint64_t sc_interface;
+	struct opal_ipmi_msg *sc_msg; /* Protected by IPMI lock */
+};
+
+static MALLOC_DEFINE(M_IPMI, "ipmi", "OPAL IPMI");
+
+static int
+opal_ipmi_polled_request(struct opal_ipmi_softc *sc, struct ipmi_request *req,
+    int timo)
+{
+	uint64_t msg_len;
+	int err;
+
+	/* Construct and send the message. */
+	sc->sc_msg->version = OPAL_IPMI_MSG_FORMAT_VERSION_1;
+	sc->sc_msg->netfn = req->ir_addr;
+	sc->sc_msg->cmd = req->ir_command;
+
+	if (req->ir_requestlen > IPMI_MAX_RX) {
+		err = ENOMEM;
+		goto out;
+	}
+	memcpy(sc->sc_msg->data, req->ir_request, req->ir_requestlen);
+
+	msg_len = sizeof(*sc->sc_msg) + req->ir_requestlen;
+	err = opal_call(OPAL_IPMI_SEND, sc->sc_interface, vtophys(sc->sc_msg),
+	    msg_len);
+	switch (err) {
+	case OPAL_SUCCESS:
+		break;
+	case OPAL_PARAMETER:
+		err = EINVAL;
+		goto out;
+	case OPAL_HARDWARE:
+		err = EIO;
+		goto out;
+	case OPAL_UNSUPPORTED:
+		err = EINVAL;
+		goto out;
+	case OPAL_RESOURCE:
+		err = ENOMEM;
+		goto out;
+	}
+
+	timo *= 10; /* Timeout is in milliseconds, we delay in 100us */
+	do {
+		msg_len = sizeof(struct opal_ipmi_msg) + IPMI_MAX_RX;
+		err = opal_call(OPAL_IPMI_RECV, sc->sc_interface,
+		    vtophys(sc->sc_msg), vtophys(&msg_len));
+		if (err != OPAL_EMPTY)
+			break;
+		DELAY(100);
+	} while (err == OPAL_EMPTY && timo-- != 0);
+
+	switch (err) {
+	case OPAL_SUCCESS:
+		/* Subtract one extra for the completion code. */
+		req->ir_replylen = msg_len - sizeof(struct opal_ipmi_msg) - 1;
+		req->ir_replylen = min(req->ir_replylen, req->ir_replybuflen);
+		memcpy(req->ir_reply, &sc->sc_msg->data[1], req->ir_replylen);
+		req->ir_compcode = sc->sc_msg->data[0];
+		break;
+	case OPAL_RESOURCE:
+		err = ENOMEM;
+		break;
+	case OPAL_EMPTY:
+		err = EAGAIN;
+		break;
+	default:
+		err = EIO;
+		break;
+	}
+
+out:
+
+	return (err);
+}
+
+static int
+opal_ipmi_probe(device_t dev)
+{
+	if (!ofw_bus_is_compatible(dev, "ibm,opal-ipmi"))
+		return (ENXIO);
+
+	device_set_desc(dev, "OPAL IPMI System Interface");
+
+	return (BUS_PROBE_DEFAULT);
+}
+
+static void
+opal_ipmi_loop(void *arg)
+{
+	struct opal_ipmi_softc *sc = arg;
+	struct ipmi_request *req;
+	int i, ok;
+
+	IPMI_LOCK(&sc->ipmi);
+	while ((req = ipmi_dequeue_request(&sc->ipmi)) != NULL) {
+		IPMI_UNLOCK(&sc->ipmi);
+		ok = 0;
+		for (i = 0; i < 3 && !ok; i++) {
+			IPMI_IO_LOCK(&sc->ipmi);
+			ok = opal_ipmi_polled_request(sc, req, MAX_TIMEOUT);
+			IPMI_IO_UNLOCK(&sc->ipmi);
+		}
+		if (ok)
+			req->ir_error = 0;
+		else
+			req->ir_error = EIO;
+		IPMI_LOCK(&sc->ipmi);
+		ipmi_complete_request(&sc->ipmi, req);
+	}
+	IPMI_UNLOCK(&sc->ipmi);
+	kproc_exit(0);
+}
+
+static int
+opal_ipmi_startup(struct ipmi_softc *sc)
+{
+
+	return (kproc_create(opal_ipmi_loop, sc, &sc->ipmi_kthread, 0, 0,
+	    "%s: opal", device_get_nameunit(sc->ipmi_dev)));
+}
+
+static int
+opal_ipmi_driver_request(struct ipmi_softc *isc, struct ipmi_request *req,
+    int timo)
+{
+	struct opal_ipmi_softc *sc = (struct opal_ipmi_softc *)isc;
+	int i, err;
+
+	for (i = 0; i < 3; i++) {
+		IPMI_LOCK(&sc->ipmi);
+		err = opal_ipmi_polled_request(sc, req, timo);
+		IPMI_UNLOCK(&sc->ipmi);
+		if (err == 0)
+			break;
+	}
+
+	req->ir_error = err;
+
+	return (err);
+}
+
+static int
+opal_ipmi_attach(device_t dev)
+{
+	struct opal_ipmi_softc *sc;
+
+	sc = device_get_softc(dev);
+
+	if (OF_getencprop(ofw_bus_get_node(dev), "ibm,ipmi-interface-id",
+	    (pcell_t*)&sc->sc_interface, sizeof(sc->sc_interface)) < 0) {
+		device_printf(dev, "Missing interface id\n");
+		return (ENXIO);
+	}
+	sc->ipmi.ipmi_startup = opal_ipmi_startup;
+	sc->ipmi.ipmi_driver_request = opal_ipmi_driver_request;
+	sc->ipmi.ipmi_dev = dev;
+
+	sc->sc_msg = malloc(sizeof(struct opal_ipmi_msg) + IPMI_MAX_RX, M_IPMI,
+	    M_WAITOK | M_ZERO);
+
+	return (ipmi_attach(dev));
+}
+
+static int
+opal_ipmi_detach(device_t dev)
+{
+	return (EBUSY);
+}
+
+static device_method_t	opal_ipmi_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		opal_ipmi_probe),
+	DEVMETHOD(device_attach,	opal_ipmi_attach),
+	DEVMETHOD(device_detach,	opal_ipmi_detach),
+	DEVMETHOD_END
+};
+
+static driver_t opal_ipmi_driver = {
+	"ipmi",
+	opal_ipmi_methods,
+	sizeof(struct opal_ipmi_softc)
+};
+
+DRIVER_MODULE(opal_ipmi, opal, opal_ipmi_driver, ipmi_devclass, NULL, NULL);