PowerNV: Initial support for OPAL I2C transfers

Add I2C OPAL driver and a set of dummy-ones to allow
all I2C things on Power8 to attach.

TODO: better async token management

Submitted by:          Wojciech Macek <wma@semihalf.com>
Obtained from:         Semihalf
Sponsored by:          IBM, QCM Technologies

1 files changed, 130 insertions, 0 deletions

diff --git a/sys/powerpc/powernv/powernv_xscom.c b/sys/powerpc/powernv/powernv_xscom.c
new file mode 100644
index 000000000000..669599e3a547
--- /dev/null
+++ b/sys/powerpc/powernv/powernv_xscom.c
@@ -0,0 +1,130 @@
+/*-
+ * Copyright (c) 2017-2018 QCM Technologies.
+ * Copyright (c) 2017-2018 Semihalf.
+ * All rights reserved.
+ *
+ * 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 AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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.
+ *
+ * $FreeBSD$
+ */
+
+#include "opt_platform.h"
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/bus.h>
+#include <sys/conf.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/mbuf.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+#include <sys/rman.h>
+#include <machine/bus.h>
+
+#ifdef FDT
+#include <dev/ofw/ofw_bus.h>
+#include <dev/ofw/ofw_bus_subr.h>
+#endif
+
+struct powernv_xscom_softc
+{
+
+};
+
+static int powernv_xscom_attach(device_t);
+static int powernv_xscom_probe(device_t);
+static const struct ofw_bus_devinfo *
+    powernv_xscom_get_devinfo(device_t, device_t);
+
+static device_method_t powernv_xscom_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		powernv_xscom_probe),
+	DEVMETHOD(device_attach,	powernv_xscom_attach),
+
+	/* ofw_bus interface */
+	DEVMETHOD(ofw_bus_get_devinfo,	powernv_xscom_get_devinfo),
+	DEVMETHOD(ofw_bus_get_compat,	ofw_bus_gen_get_compat),
+	DEVMETHOD(ofw_bus_get_model,	ofw_bus_gen_get_model),
+	DEVMETHOD(ofw_bus_get_name,	ofw_bus_gen_get_name),
+	DEVMETHOD(ofw_bus_get_node,	ofw_bus_gen_get_node),
+	DEVMETHOD(ofw_bus_get_type,	ofw_bus_gen_get_type),
+
+	DEVMETHOD_END
+};
+
+static devclass_t powernv_xscom_devclass;
+
+static int
+powernv_xscom_probe(device_t dev)
+{
+
+	if (!(ofw_bus_is_compatible(dev, "ibm,xscom")))
+		return (ENXIO);
+
+	device_set_desc(dev, "xscom");
+	return (0);
+}
+
+static int
+powernv_xscom_attach(device_t dev)
+{
+	phandle_t child;
+	device_t cdev;
+	struct ofw_bus_devinfo *dinfo;
+
+	for (child = OF_child(ofw_bus_get_node(dev)); child != 0;
+	    child = OF_peer(child)) {
+		dinfo = malloc(sizeof(*dinfo), M_DEVBUF, M_WAITOK | M_ZERO);
+		if (ofw_bus_gen_setup_devinfo(dinfo, child) != 0) {
+			free(dinfo, M_DEVBUF);
+			continue;
+		}
+		cdev = device_add_child(dev, NULL, -1);
+		if (cdev == NULL) {
+			device_printf(dev, "<%s>: device_add_child failed\n",
+			    dinfo->obd_name);
+			ofw_bus_gen_destroy_devinfo(dinfo);
+			free(dinfo, M_DEVBUF);
+			continue;
+		}
+		device_set_ivars(cdev, dinfo);
+	}
+
+	return (bus_generic_attach(dev));
+}
+
+static const struct ofw_bus_devinfo *
+powernv_xscom_get_devinfo(device_t dev, device_t child)
+{
+        return (device_get_ivars(child));
+}
+
+DEFINE_CLASS_0(powernv_xscom, powernv_xscom_driver, powernv_xscom_methods,
+    sizeof(struct powernv_xscom_softc));
+DRIVER_MODULE(powernv_xscom, ofwbus, powernv_xscom_driver, powernv_xscom_devclass, NULL,
+    NULL);
+