Introduce palmbus for Mediatek/Ralink SoCs

This allows us to get closer to OpenWRT DTS files and minimize the diffs
a little more.

Approved by:	adrian (mentor)
Sponsored by:	Smartcom - Bulgaria AD
Differential Revision:	https://reviews.freebsd.org/D6042

1 files changed, 81 insertions, 0 deletions

diff --git a/sys/mips/mediatek/palmbus.c b/sys/mips/mediatek/palmbus.c
new file mode 100644
index 0000000..5fe1430
--- /dev/null
+++ b/sys/mips/mediatek/palmbus.c
@@ -0,0 +1,81 @@
+/*-
+ * Copyright (c) 2016 Stanislav Galabov.
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/module.h>
+#include <sys/bus.h>
+#include <sys/conf.h>
+#include <sys/kernel.h>
+#include <sys/rman.h>
+
+#include <dev/ofw/openfirm.h>
+#include <dev/ofw/ofw_bus.h>
+#include <dev/ofw/ofw_bus_subr.h>
+
+#include <dev/fdt/simplebus.h>
+
+/*
+ * Driver for Mediatek/Ralink Palmbus
+ *
+ * Currently the only reason for the existence of this driver is so that we can
+ * minimize the changes required to the upstream DTS files we use.
+ * Otherwise palmbus is a very simple subclass of our simplebus and the only
+ * difference between the two is the actual value of the compatible property.
+ */
+
+static int
+palmbus_probe(device_t dev)
+{
+
+	if (!ofw_bus_status_okay(dev))
+		return (ENXIO);
+
+	if (!(ofw_bus_is_compatible(dev, "palmbus") &&
+	    ofw_bus_has_prop(dev, "ranges")) &&
+	    (ofw_bus_get_type(dev) == NULL || strcmp(ofw_bus_get_type(dev),
+	    "soc") != 0))
+		return (ENXIO);
+
+	device_set_desc(dev, "MTK Palmbus");
+
+	return (0);
+}
+
+static device_method_t palmbus_methods[] = {
+	DEVMETHOD(device_probe,		palmbus_probe),
+
+	DEVMETHOD_END
+};
+
+DEFINE_CLASS_1(palmbus, palmbus_driver, palmbus_methods,
+    sizeof(struct simplebus_softc), simplebus_driver);
+static devclass_t palmbus_devclass;
+EARLY_DRIVER_MODULE(palmbus, ofwbus, palmbus_driver, palmbus_devclass, 0, 0,
+    BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
+MODULE_VERSION(palmbus, 1);