Modularize the Open Firmware client interface to allow run-time switching

of OFW access semantics, in order to allow future support for real-mode
OF access and flattened device frees. OF client interface modules are
implemented using KOBJ, in a similar way to the PPC PMAP modules.

Because we need Open Firmware to be available before mutexes can be used on
sparc64, changes are also included to allow KOBJ to be used very early in
the boot process by only using the mutex once we know it has been initialized.

Reviewed by:    marius, grehan

7 files changed, 1375 insertions, 585 deletions

diff --git a/sys/dev/ofw/ofw_if.m b/sys/dev/ofw/ofw_if.m
new file mode 100644
index 0000000..431ac91
--- /dev/null
+++ b/sys/dev/ofw/ofw_if.m
@@ -0,0 +1,357 @@
+#-
+# Copyright (c) 2008 Nathan Whitehorn
+# 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 <dev/ofw/openfirm.h>
+#include <dev/ofw/ofwvar.h>
+
+/**
+ * @defgroup OFW ofw - KObj methods for Open Firmware RTAS implementations
+ * @brief A set of methods to implement the Open Firmware client side interface.
+ *@{
+ */
+
+INTERFACE ofw;
+
+/**
+ * @brief Initialize OFW client interface
+ *
+ * @param _cookie	A handle to the client interface, generally the OF
+ *			callback routine.
+ */
+METHOD void init {
+	ofw_t		_ofw;
+	void		*_cookie;
+};
+
+/**
+ * @brief Return next sibling of node
+ *
+ * @param _node		Selected node
+ */
+METHOD phandle_t peer {
+	ofw_t		_ofw;
+	phandle_t 	_node;
+};
+
+/**
+ * @brief Return parent of node
+ *
+ * @param _node		Selected node
+ */
+METHOD phandle_t parent {
+	ofw_t		_ofw;
+	phandle_t 	_node;
+};
+
+/**
+ * @brief Return first child of node
+ *
+ * @param _node		Selected node
+ */
+METHOD phandle_t child {
+	ofw_t		_ofw;
+	phandle_t 	_node;
+};
+
+/**
+ * @brief Return package corresponding to instance
+ *
+ * @param _handle	Selected instance
+ */
+METHOD phandle_t instance_to_package {
+	ofw_t		_ofw;
+	ihandle_t 	_handle;
+};
+
+/**
+ * @brief Return length of node property
+ *
+ * @param _node		Selected node
+ * @param _prop		Property name
+ */
+METHOD ssize_t getproplen {
+	ofw_t		_ofw;
+	phandle_t 	_node;
+	const char 	*_prop;
+};
+
+/**
+ * @brief Read node property
+ *
+ * @param _node		Selected node
+ * @param _prop		Property name
+ * @param _buf		Pointer to buffer
+ * @param _size		Size of buffer
+ */
+METHOD ssize_t getprop {
+	ofw_t		_ofw;
+	phandle_t 	_node;
+	const char	*_prop;
+	void		*_buf;
+	size_t		_size;
+};
+
+/**
+ * @brief Get next property name
+ *
+ * @param _node		Selected node
+ * @param _prop		Current property name
+ * @param _buf		Buffer for next property name
+ * @param _size		Size of buffer
+ */
+METHOD int nextprop {
+	ofw_t		_ofw;
+	phandle_t 	_node;
+	const char	*_prop;
+	char 		*_buf;
+	size_t		_size;
+};
+
+/**
+ * @brief Set property
+ *
+ * @param _node		Selected node
+ * @param _prop		Property name
+ * @param _buf		Value to set
+ * @param _size		Size of buffer
+ */
+METHOD int setprop {
+	ofw_t		_ofw;
+	phandle_t 	_node;
+	const char 	*_prop;
+	const void	*_buf;
+	size_t		_size;
+};
+
+/**
+ * @brief Canonicalize path
+ *
+ * @param _path		Path to canonicalize
+ * @param _buf		Buffer for canonicalized path
+ * @param _size		Size of buffer
+ */
+METHOD ssize_t canon {
+	ofw_t		_ofw;
+	const char	*_path;
+	char		*_buf;
+	size_t		_size;
+};
+
+/**
+ * @brief Return phandle for named device
+ *
+ * @param _path		Device path
+ */
+METHOD phandle_t finddevice {
+	ofw_t		_ofw;
+	const char 	*_path;
+};
+
+/**
+ * @brief Return path for node instance
+ *
+ * @param _handle	Instance handle
+ * @param _path		Buffer for path
+ * @param _size		Size of buffer
+ */
+METHOD ssize_t instance_to_path {
+	ofw_t		_ofw;
+	ihandle_t	_handle;
+	char	 	*_path;
+	size_t		_size;
+};
+
+/**
+ * @brief Return path for node
+ *
+ * @param _node		Package node
+ * @param _path		Buffer for path
+ * @param _size		Size of buffer
+ */
+METHOD ssize_t package_to_path {
+	ofw_t		_ofw;
+	phandle_t	_node;
+	char	 	*_path;
+	size_t		_size;
+};
+
+
+# Methods for OF method calls (optional)
+
+/**
+ * @brief Test to see if a service exists.
+ *
+ * @param _name		name of the service
+ */
+METHOD int test {
+	ofw_t		_ofw;
+	const char	*_name;
+};
+
+/**
+ * @brief Call method belonging to an instance handle
+ *
+ * @param _instance	Instance handle
+ * @param _method	Method name
+ * @param _nargs	Number of arguments
+ * @param _nreturns	Number of return values
+ * @param _args_and_returns	Values for arguments, followed by returns
+ */
+
+METHOD int call_method {
+	ofw_t		_ofw;
+	ihandle_t	_instance;
+	const char	*_method;
+	int		_nargs;
+	int 		_nreturns;
+
+	unsigned long	*_args_and_returns;
+};
+
+/**
+ * @brief Interpret a forth command
+ *
+ * @param _cmd		Command
+ * @param _nreturns	Number of return values
+ * @param _returns	Values for returns
+ */
+
+METHOD int interpret {
+	ofw_t		_ofw;
+	const char	*_cmd;
+	int 		_nreturns;
+	unsigned long	*_returns;
+};
+
+# Device I/O Functions (optional)
+
+/**
+ * @brief Open node, returning instance handle
+ *
+ * @param _path		Path to node
+ */
+METHOD ihandle_t open {
+	ofw_t		_ofw;
+	const char	*_path;
+}
+
+/**
+ * @brief Close node instance
+ *
+ * @param _instance	Instance to close
+ */
+METHOD void close {
+	ofw_t		_ofw;
+	ihandle_t	_instance;
+}
+
+/**
+ * @brief Read from device
+ *
+ * @param _instance	Device instance
+ * @param _buf		Buffer to read to
+ * @param _size		Size of buffer
+ */
+METHOD ssize_t read {
+	ofw_t		_ofw;
+	ihandle_t	_instance;
+	void		*_buf;
+	size_t		size;
+}
+
+/**
+ * @brief Write to device
+ *
+ * @param _instance	Device instance
+ * @param _buf		Buffer to write from
+ * @param _size		Size of buffer
+ */
+METHOD ssize_t write {
+	ofw_t		_ofw;
+	ihandle_t	_instance;
+	const void	*_buf;
+	size_t		size;
+}
+
+/**
+ * @brief Seek device
+ *
+ * @param _instance	Device instance
+ * @param _off		Offset to which to seek
+ */
+METHOD int seek {
+	ofw_t		_ofw;
+	ihandle_t	_instance;
+	uint64_t	_off;
+}
+
+# Open Firmware memory management
+
+/**
+ * @brief Claim virtual memory
+ *
+ * @param _addr		Requested memory location (NULL for first available)
+ * @param _size		Requested size in bytes
+ * @param _align	Requested alignment
+ */
+METHOD caddr_t claim {
+	ofw_t		_ofw;
+	void		*_addr;
+	size_t		_size;
+	u_int		_align;
+}
+
+/**
+ * @brief Release virtual memory
+ *
+ * @param _addr		Memory location
+ * @param _size		Size in bytes
+ */
+METHOD void release {
+	ofw_t		_ofw;
+	void		*_addr;
+	size_t		_size;
+};
+
+# Commands for returning control to the firmware
+
+/**
+ * @brief Temporarily return control to firmware
+ */
+METHOD void enter {
+	ofw_t		_ofw;
+};
+
+/**
+ * @brief Halt and return control to firmware
+ */
+METHOD void exit {
+	ofw_t		_ofw;
+};
+
+
diff --git a/sys/dev/ofw/ofw_standard.c b/sys/dev/ofw/ofw_standard.c
new file mode 100644
index 0000000..e097145
--- /dev/null
+++ b/sys/dev/ofw/ofw_standard.c
@@ -0,0 +1,763 @@
+/*	$NetBSD: Locore.c,v 1.7 2000/08/20 07:04:59 tsubai Exp $	*/
+
+/*-
+ * Copyright (C) 1995, 1996 Wolfgang Solfrank.
+ * Copyright (C) 1995, 1996 TooLs GmbH.
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by TooLs GmbH.
+ * 4. The name of TooLs GmbH may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``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.
+ */
+/*-
+ * Copyright (C) 2000 Benno Rice.
+ * 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 Benno Rice ``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/malloc.h>
+#include <sys/systm.h>
+
+#include <machine/stdarg.h>
+
+#include <dev/ofw/openfirm.h>
+#include <dev/ofw/ofwvar.h>
+#include "ofw_if.h"
+
+static void ofw_std_init(ofw_t ofw, void *openfirm);
+static int ofw_std_test(ofw_t ofw, const char *name);
+static int ofw_std_interpret(ofw_t ofw, const char *cmd, int nreturns,
+    unsigned long *returns);
+static phandle_t ofw_std_peer(ofw_t ofw, phandle_t node);
+static phandle_t ofw_std_child(ofw_t ofw, phandle_t node);
+static phandle_t ofw_std_parent(ofw_t ofw, phandle_t node);
+static phandle_t ofw_std_instance_to_package(ofw_t ofw, ihandle_t instance);
+static ssize_t ofw_std_getproplen(ofw_t ofw, phandle_t package,
+    const char *propname);
+static ssize_t ofw_std_getprop(ofw_t ofw, phandle_t package,
+    const char *propname, void *buf, size_t buflen);
+static int ofw_std_nextprop(ofw_t ofw, phandle_t package, const char *previous,
+    char *buf, size_t);
+static int ofw_std_setprop(ofw_t ofw, phandle_t package, char *propname,
+    void *buf, size_t len);
+static ssize_t ofw_std_canon(ofw_t ofw, const char *device, char *buf,
+    size_t len);
+static phandle_t ofw_std_finddevice(ofw_t ofw, const char *device);
+static ssize_t ofw_std_instance_to_path(ofw_t ofw, ihandle_t instance,
+    char *buf, size_t len);
+static ssize_t ofw_std_package_to_path(ofw_t ofw, phandle_t package, char *buf,
+    size_t len);
+static int ofw_std_call_method(ofw_t ofw, ihandle_t instance,
+    const char *method, int nargs, int nreturns,
+    unsigned long *args_and_returns);
+static ihandle_t ofw_std_open(ofw_t ofw, const char *device);
+static void ofw_std_close(ofw_t ofw, ihandle_t instance);
+static ssize_t ofw_std_read(ofw_t ofw, ihandle_t instance, void *addr,
+    size_t len);
+static ssize_t ofw_std_write(ofw_t ofw, ihandle_t instance, const void *addr,
+    size_t len);
+static int ofw_std_seek(ofw_t ofw, ihandle_t instance, u_int64_t pos);
+static caddr_t ofw_std_claim(ofw_t ofw, void *virt, size_t size, u_int align);
+static void ofw_std_release(ofw_t ofw, void *virt, size_t size);
+static void ofw_std_enter(ofw_t ofw);
+static void ofw_std_exit(ofw_t ofw);
+
+static ofw_method_t ofw_std_methods[] = {
+	OFWMETHOD(ofw_init,			ofw_std_init),
+	OFWMETHOD(ofw_peer,			ofw_std_peer),
+	OFWMETHOD(ofw_child,			ofw_std_child),
+	OFWMETHOD(ofw_parent,			ofw_std_parent),
+	OFWMETHOD(ofw_instance_to_package,	ofw_std_instance_to_package),
+	OFWMETHOD(ofw_getproplen,		ofw_std_getproplen),
+	OFWMETHOD(ofw_getprop,			ofw_std_getprop),
+	OFWMETHOD(ofw_nextprop,			ofw_std_nextprop),
+	OFWMETHOD(ofw_setprop,			ofw_std_setprop),
+	OFWMETHOD(ofw_canon,			ofw_std_canon),
+	OFWMETHOD(ofw_finddevice,		ofw_std_finddevice),
+	OFWMETHOD(ofw_instance_to_path,		ofw_std_instance_to_path),
+	OFWMETHOD(ofw_package_to_path,		ofw_std_package_to_path),
+
+	OFWMETHOD(ofw_test,			ofw_std_test),
+	OFWMETHOD(ofw_call_method,		ofw_std_call_method),
+	OFWMETHOD(ofw_interpret,		ofw_std_interpret),
+	OFWMETHOD(ofw_open,			ofw_std_open),
+	OFWMETHOD(ofw_close,			ofw_std_close),
+	OFWMETHOD(ofw_read,			ofw_std_read),
+	OFWMETHOD(ofw_write,			ofw_std_write),
+	OFWMETHOD(ofw_seek,			ofw_std_seek),
+	OFWMETHOD(ofw_claim,			ofw_std_claim),
+	OFWMETHOD(ofw_release,			ofw_std_release),
+	OFWMETHOD(ofw_enter,			ofw_std_enter),
+	OFWMETHOD(ofw_exit,			ofw_std_exit),
+
+	{ 0, 0 }
+};
+
+static ofw_def_t ofw_std = {
+	OFW_STD_DIRECT,
+	ofw_std_methods,
+	0
+};
+OFW_DEF(ofw_std);
+
+static int (*openfirmware)(void *);
+
+/* Initialiser */
+
+static void
+ofw_std_init(ofw_t ofw, void *openfirm)
+{
+	openfirmware = (int (*)(void *))openfirm;
+}
+
+/*
+ * Generic functions
+ */
+
+/* Test to see if a service exists. */
+static int
+ofw_std_test(ofw_t ofw, const char *name)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t service;
+		cell_t missing;
+	} args = {
+		(cell_t)"test",
+		1,
+		1,
+	};
+
+	args.service = (cell_t)name;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.missing);
+}
+
+static int
+ofw_std_interpret(ofw_t ofw, const char *cmd, int nreturns,
+    unsigned long *returns)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t slot[16];
+	} args = {
+		(cell_t)"interpret",
+		1,
+	};
+	cell_t status;
+	int i = 0, j = 0;
+
+	args.nreturns = ++nreturns;
+	args.slot[i++] = (cell_t)cmd;
+	if (openfirmware(&args) == -1) {
+		return (-1);
+	}
+	status = args.slot[i++];
+	while (i < 1 + nreturns)
+		returns[j] = args.slot[i++];
+	return (status);
+}
+
+/*
+ * Device tree functions
+ */
+
+/* Return the next sibling of this node or 0. */
+static phandle_t
+ofw_std_peer(ofw_t ofw, phandle_t node)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t node;
+		cell_t next;
+	} args = {
+		(cell_t)"peer",
+		1,
+		1,
+	};
+
+	args.node = node;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.next);
+}
+
+/* Return the first child of this node or 0. */
+static phandle_t
+ofw_std_child(ofw_t ofw, phandle_t node)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t node;
+		cell_t child;
+	} args = {
+		(cell_t)"child",
+		1,
+		1,
+	};
+
+	args.node = node;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.child);
+}
+
+/* Return the parent of this node or 0. */
+static phandle_t
+ofw_std_parent(ofw_t ofw, phandle_t node)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t node;
+		cell_t parent;
+	} args = {
+		(cell_t)"parent",
+		1,
+		1,
+	};
+
+	args.node = node;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.parent);
+}
+
+/* Return the package handle that corresponds to an instance handle. */
+static phandle_t
+ofw_std_instance_to_package(ofw_t ofw, ihandle_t instance)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t instance;
+		cell_t package;
+	} args = {
+		(cell_t)"instance-to-package",
+		1,
+		1,
+	};
+
+	args.instance = instance;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.package);
+}
+
+/* Get the length of a property of a package. */
+static ssize_t
+ofw_std_getproplen(ofw_t ofw, phandle_t package, const char *propname)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t package;
+		cell_t propname;
+		cell_t proplen;
+	} args = {
+		(cell_t)"getproplen",
+		2,
+		1,
+	};
+
+	args.package = package;
+	args.propname = (cell_t)propname;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.proplen);
+}
+
+/* Get the value of a property of a package. */
+static ssize_t
+ofw_std_getprop(ofw_t ofw, phandle_t package, const char *propname, void *buf,
+    size_t buflen)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t package;
+		cell_t propname;
+		cell_t buf;
+		cell_t buflen;
+		cell_t size;
+	} args = {
+		(cell_t)"getprop",
+		4,
+		1,
+	};
+
+	args.package = package;
+	args.propname = (cell_t)propname;
+	args.buf = (cell_t)buf;
+	args.buflen = buflen;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.size);
+}
+
+/* Get the next property of a package. */
+static int
+ofw_std_nextprop(ofw_t ofw, phandle_t package, const char *previous, char *buf,
+    size_t size)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t package;
+		cell_t previous;
+		cell_t buf;
+		cell_t flag;
+	} args = {
+		(cell_t)"nextprop",
+		3,
+		1,
+	};
+
+	args.package = package;
+	args.previous = (cell_t)previous;
+	args.buf = (cell_t)buf;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.flag);
+}
+
+/* Set the value of a property of a package. */
+/* XXX Has a bug on FirePower */
+static int
+ofw_std_setprop(ofw_t ofw, phandle_t package, char *propname, void *buf,
+    size_t len)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t package;
+		cell_t propname;
+		cell_t buf;
+		cell_t len;
+		cell_t size;
+	} args = {
+		(cell_t)"setprop",
+		4,
+		1,
+	};
+
+	args.package = package;
+	args.propname = (cell_t)propname;
+	args.buf = (cell_t)buf;
+	args.len = len;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.size);
+}
+
+/* Convert a device specifier to a fully qualified pathname. */
+static ssize_t
+ofw_std_canon(ofw_t ofw, const char *device, char *buf, size_t len)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t device;
+		cell_t buf;
+		cell_t len;
+		cell_t size;
+	} args = {
+		(cell_t)"canon",
+		3,
+		1,
+	};
+
+	args.device = (cell_t)device;
+	args.buf = (cell_t)buf;
+	args.len = len;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.size);
+}
+
+/* Return a package handle for the specified device. */
+static phandle_t
+ofw_std_finddevice(ofw_t ofw, const char *device)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t device;
+		cell_t package;
+	} args = {
+		(cell_t)"finddevice",
+		1,
+		1,
+	};
+
+	args.device = (cell_t)device;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.package);
+}
+
+/* Return the fully qualified pathname corresponding to an instance. */
+static ssize_t
+ofw_std_instance_to_path(ofw_t ofw, ihandle_t instance, char *buf, size_t len)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t instance;
+		cell_t buf;
+		cell_t len;
+		cell_t size;
+	} args = {
+		(cell_t)"instance-to-path",
+		3,
+		1,
+	};
+
+	args.instance = instance;
+	args.buf = (cell_t)buf;
+	args.len = len;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.size);
+}
+
+/* Return the fully qualified pathname corresponding to a package. */
+static ssize_t
+ofw_std_package_to_path(ofw_t ofw, phandle_t package, char *buf, size_t len)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t package;
+		cell_t buf;
+		cell_t len;
+		cell_t size;
+	} args = {
+		(cell_t)"package-to-path",
+		3,
+		1,
+	};
+
+	args.package = package;
+	args.buf = (cell_t)buf;
+	args.len = len;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.size);
+}
+
+/*  Call the method in the scope of a given instance. */
+static int
+ofw_std_call_method(ofw_t ofw, ihandle_t instance, const char *method,
+    int nargs, int nreturns, unsigned long *args_and_returns)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t method;
+		cell_t instance;
+		cell_t args_n_results[12];
+	} args = {
+		(cell_t)"call-method",
+		2,
+		1,
+	};
+	cell_t *cp;
+	unsigned long *ap;
+	int n;
+
+	if (nargs > 6)
+		return (-1);
+	args.nargs = nargs + 2;
+	args.nreturns = nreturns + 1;
+	args.method = (cell_t)method;
+	args.instance = instance;
+
+	ap = args_and_returns;
+	for (cp = args.args_n_results + (n = nargs); --n >= 0;)
+		*--cp = *(ap++);
+	if (openfirmware(&args) == -1)
+		return (-1);
+	if (args.args_n_results[nargs])
+		return (args.args_n_results[nargs]);
+	for (cp = args.args_n_results + nargs + (n = args.nreturns); --n > 0;)
+		*(ap++) = *--cp;
+	return (0);
+}
+
+/*
+ * Device I/O functions
+ */
+
+/* Open an instance for a device. */
+static ihandle_t
+ofw_std_open(ofw_t ofw, const char *device)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t device;
+		cell_t instance;
+	} args = {
+		(cell_t)"open",
+		1,
+		1,
+	};
+
+	args.device = (cell_t)device;
+	if (openfirmware(&args) == -1 || args.instance == 0) {
+		return (-1);
+	}
+	return (args.instance);
+}
+
+/* Close an instance. */
+static void
+ofw_std_close(ofw_t ofw, ihandle_t instance)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t instance;
+	} args = {
+		(cell_t)"close",
+		1,
+	};
+
+	args.instance = instance;
+	openfirmware(&args);
+}
+
+/* Read from an instance. */
+static ssize_t
+ofw_std_read(ofw_t ofw, ihandle_t instance, void *addr, size_t len)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t instance;
+		cell_t addr;
+		cell_t len;
+		cell_t actual;
+	} args = {
+		(cell_t)"read",
+		3,
+		1,
+	};
+
+	args.instance = instance;
+	args.addr = (cell_t)addr;
+	args.len = len;
+	if (openfirmware(&args) == -1)
+		return (-1);
+
+	return (args.actual);
+}
+
+/* Write to an instance. */
+static ssize_t
+ofw_std_write(ofw_t ofw, ihandle_t instance, const void *addr, size_t len)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t instance;
+		cell_t addr;
+		cell_t len;
+		cell_t actual;
+	} args = {
+		(cell_t)"write",
+		3,
+		1,
+	};
+
+	args.instance = instance;
+	args.addr = (cell_t)addr;
+	args.len = len;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.actual);
+}
+
+/* Seek to a position. */
+static int
+ofw_std_seek(ofw_t ofw, ihandle_t instance, u_int64_t pos)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t instance;
+		cell_t poshi;
+		cell_t poslo;
+		cell_t status;
+	} args = {
+		(cell_t)"seek",
+		3,
+		1,
+	};
+
+	args.instance = instance;
+	args.poshi = pos >> 32;
+	args.poslo = pos;
+	if (openfirmware(&args) == -1)
+		return (-1);
+	return (args.status);
+}
+
+/*
+ * Memory functions
+ */
+
+/* Claim an area of memory. */
+static caddr_t
+ofw_std_claim(ofw_t ofw, void *virt, size_t size, u_int align)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t virt;
+		cell_t size;
+		cell_t align;
+		cell_t baseaddr;
+	} args = {
+		(cell_t)"claim",
+		3,
+		1,
+	};
+
+	args.virt = (cell_t)virt;
+	args.size = size;
+	args.align = align;
+	if (openfirmware(&args) == -1)
+		return ((void *)-1);
+	return ((void *)args.baseaddr);
+}
+
+/* Release an area of memory. */
+static void
+ofw_std_release(ofw_t ofw, void *virt, size_t size)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+		cell_t virt;
+		cell_t size;
+	} args = {
+		(cell_t)"release",
+		2,
+	};
+
+	args.virt = (cell_t)virt;
+	args.size = size;
+	openfirmware(&args);
+}
+
+/*
+ * Control transfer functions
+ */
+
+/* Suspend and drop back to the Open Firmware interface. */
+static void
+ofw_std_enter(ofw_t ofw)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+	} args = {
+		(cell_t)"enter",
+	};
+
+	openfirmware(&args);
+	/* We may come back. */
+}
+
+/* Shut down and drop back to the Open Firmware interface. */
+static void
+ofw_std_exit(ofw_t ofw)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+	} args = {
+		(cell_t)"exit",
+	};
+
+	openfirmware(&args);
+	for (;;)			/* just in case */
+		;
+}
+
diff --git a/sys/dev/ofw/ofwvar.h b/sys/dev/ofw/ofwvar.h
new file mode 100644
index 0000000..950dded
--- /dev/null
+++ b/sys/dev/ofw/ofwvar.h
@@ -0,0 +1,89 @@
+/*-
+ * Copyright (c) 2005 Peter Grehan
+ * Copyright (c) 2008 Nathan Whitehorn
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _OFW_OFWVAR_H_
+#define _OFW_OFWVAR_H_
+
+/*
+ * An Open Firmware client implementation is declared with a kernel object and
+ * an associated method table, similar to a device driver.
+ *
+ * e.g.
+ *
+ * static ofw_method_t fdt_methods[] = {
+ *	OFWMETHOD(ofw_init,		fdt_init),
+ *	OFWMETHOD(ofw_finddevice,	fdt_finddevice),
+ *  ...
+ *	OFWMETHOD(ofw_nextprop,		fdt_nextprop),
+ *	{ 0, 0 }
+ * };
+ *
+ * static ofw_def_t ofw_fdt = {
+ * 	"ofw_fdt",
+ *	fdt_methods,
+ *	sizeof(fdt_softc),	// or 0 if no softc
+ * };
+ *
+ * OFW_DEF(ofw_fdt);
+ */
+
+#include <sys/kobj.h>
+
+struct ofw_kobj {
+	/*
+	 * An OFW instance is a kernel object.
+	 */
+	KOBJ_FIELDS;
+
+	/*
+	 * Utility elements that an instance may use
+	 */
+	struct mtx	ofw_mtx;	/* available for instance use */
+	void		*ofw_iptr;	/* instance data pointer */
+
+	/*
+	 * Opaque data that can be overlaid with an instance-private
+	 * structure. OFW code can test that this is large enough at
+	 * compile time with a sizeof() test againt it's softc. There
+	 * is also a run-time test when the MMU kernel object is
+	 * registered.
+	 */
+#define OFW_OPAQUESZ	64
+	u_int		ofw_opaque[OFW_OPAQUESZ];
+};
+
+typedef struct ofw_kobj		*ofw_t;
+typedef struct kobj_class	ofw_def_t;
+
+#define ofw_method_t	kobj_method_t
+#define OFWMETHOD	KOBJMETHOD
+
+#define OFW_DEF(name)	DATA_SET(ofw_set, name)
+
+#endif /* _OFW_OFWVAR_H_ */
diff --git a/sys/dev/ofw/openfirm.c b/sys/dev/ofw/openfirm.c
index ff889e5..c7b2203 100644
--- a/sys/dev/ofw/openfirm.c
+++ b/sys/dev/ofw/openfirm.c
@@ -66,23 +66,70 @@ __FBSDID("$FreeBSD$");
 #include <machine/stdarg.h>
 
 #include <dev/ofw/openfirm.h>
+#include <dev/ofw/ofwvar.h>
+
+#include "ofw_if.h"
 
 MALLOC_DEFINE(M_OFWPROP, "openfirm", "Open Firmware properties");
 
 static ihandle_t stdout;
 
+static ofw_def_t	*ofw_def_impl;
+static ofw_t		ofw_obj;
+static struct ofw_kobj	ofw_kernel_obj;
+static struct kobj_ops	ofw_kernel_kops;
+
+/*
+ * OFW install routines. Highest priority wins, equal priority also
+ * overrides allowing last-set to win.
+ */
+SET_DECLARE(ofw_set, ofw_def_t);
+
+boolean_t
+OF_install(char *name, int prio)
+{
+	ofw_def_t  **ofwpp, *ofwp;
+	static int curr_prio = 0;
+
+	/*
+	* Try and locate the OFW kobj corresponding to the name
+	*/
+	SET_FOREACH(ofwpp, ofw_set) {
+		ofwp = *ofwpp;
+
+		if (ofwp->name &&
+		    !strcmp(ofwp->name, name) &&
+		    prio >= curr_prio) {
+			curr_prio = prio;
+			ofw_def_impl = ofwp;
+			return (TRUE);
+		}
+	}
+
+	return (FALSE);
+}
+
 /* Initialiser */
 
 void
-OF_init(int (*openfirm)(void *))
+OF_init(void *cookie)
 {
 	phandle_t chosen;
 
-	set_openfirm_callback(openfirm);
+	ofw_obj = &ofw_kernel_obj;
+	/*
+	 * Take care of compiling the selected class, and
+	 * then statically initialize the OFW object
+	 */
+	kobj_class_compile_static(ofw_def_impl, &ofw_kernel_kops);
+	kobj_init((kobj_t)ofw_obj, ofw_def_impl);
+
+	OFW_INIT(ofw_obj, cookie);
+
 	if ((chosen = OF_finddevice("/chosen")) == -1)
 		OF_exit();
 	if (OF_getprop(chosen, "stdout", &stdout, sizeof(stdout)) == -1)
-		OF_exit();
+		stdout = -1;
 }
 
 void
@@ -103,75 +150,27 @@ OF_printf(const char *fmt, ...)
 
 /* Test to see if a service exists. */
 int
-OF_test(char *name)
+OF_test(const char *name)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t service;
-		cell_t missing;
-	} args = {
-		(cell_t)"test",
-		1,
-		1,
-	};
-
-	args.service = (cell_t)name;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.missing);
+	return (OFW_TEST(ofw_obj, name));
 }
 
 int
-OF_interpret(char *cmd, int nreturns, ...)
+OF_interpret(const char *cmd, int nreturns, ...)
 {
 	va_list ap;
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t slot[16];
-	} args = {
-		(cell_t)"interpret",
-		1,
-	};
-	cell_t status;
+	unsigned long slots[16];
 	int i = 0;
+	int status;
+
+	status = OFW_INTERPRET(ofw_obj, cmd, nreturns, slots);
 
 	va_start(ap, nreturns);
-	args.nreturns = ++nreturns;
-	args.slot[i++] = (cell_t)cmd;
-	while (i < 1)
-		args.slot[i++] = va_arg(ap, cell_t);
-	if (openfirmware(&args) == -1) {
-		va_end(ap);
-		return (-1);
-	}
-	status = args.slot[i++];
 	while (i < 1 + nreturns)
-		*va_arg(ap, cell_t *) = args.slot[i++];
+		*va_arg(ap, cell_t *) = slots[i++];
 	va_end(ap);
-	return (status);
-}
 
-/* Return firmware millisecond count. */
-int
-OF_milliseconds()
-{
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t ms;
-	} args = {
-		(cell_t)"milliseconds",
-		0,
-		1,
-	};
-
-	openfirmware(&args);
-	return (args.ms);
+	return (status);
 }
 
 /*
@@ -182,140 +181,42 @@ OF_milliseconds()
 phandle_t
 OF_peer(phandle_t node)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t node;
-		cell_t next;
-	} args = {
-		(cell_t)"peer",
-		1,
-		1,
-	};
-
-	args.node = node;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.next);
+	return (OFW_PEER(ofw_obj, node));
 }
 
 /* Return the first child of this node or 0. */
 phandle_t
 OF_child(phandle_t node)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t node;
-		cell_t child;
-	} args = {
-		(cell_t)"child",
-		1,
-		1,
-	};
-
-	args.node = node;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.child);
+	return (OFW_CHILD(ofw_obj, node));
 }
 
 /* Return the parent of this node or 0. */
 phandle_t
 OF_parent(phandle_t node)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t node;
-		cell_t parent;
-	} args = {
-		(cell_t)"parent",
-		1,
-		1,
-	};
-
-	args.node = node;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.parent);
+	return (OFW_PARENT(ofw_obj, node));
 }
 
 /* Return the package handle that corresponds to an instance handle. */
 phandle_t
 OF_instance_to_package(ihandle_t instance)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t instance;
-		cell_t package;
-	} args = {
-		(cell_t)"instance-to-package",
-		1,
-		1,
-	};
-
-	args.instance = instance;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.package);
+	return (OFW_INSTANCE_TO_PACKAGE(ofw_obj, instance));
 }
 
 /* Get the length of a property of a package. */
-int
-OF_getproplen(phandle_t package, char *propname)
+ssize_t
+OF_getproplen(phandle_t package, const char *propname)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t package;
-		cell_t propname;
-		cell_t proplen;
-	} args = {
-		(cell_t)"getproplen",
-		2,
-		1,
-	};
-
-	args.package = package;
-	args.propname = (cell_t)propname;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.proplen);
+	return (OFW_GETPROPLEN(ofw_obj, package, propname));
 }
 
 /* Get the value of a property of a package. */
-int
-OF_getprop(phandle_t package, char *propname, void *buf, int buflen)
+ssize_t
+OF_getprop(phandle_t package, const char *propname, void *buf, size_t buflen)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t package;
-		cell_t propname;
-		cell_t buf;
-		cell_t buflen;
-		cell_t size;
-	} args = {
-		(cell_t)"getprop",
-		4,
-		1,
-	};
-
-	args.package = package;
-	args.propname = (cell_t)propname;
-	args.buf = (cell_t)buf;
-	args.buflen = buflen;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.size);
+	return (OFW_GETPROP(ofw_obj, package, propname, buf, buflen));
 }
 
 /*
@@ -323,8 +224,8 @@ OF_getprop(phandle_t package, char *propname, void *buf, int buflen)
  * (using the M_OFWPROP malloc pool and M_WAITOK). elsz is the size of a
  * single element, the number of elements is return in number.
  */
-int
-OF_getprop_alloc(phandle_t package, char *propname, int elsz, void **buf)
+ssize_t
+OF_getprop_alloc(phandle_t package, const char *propname, int elsz, void **buf)
 {
 	int len;
 
@@ -344,194 +245,69 @@ OF_getprop_alloc(phandle_t package, char *propname, int elsz, void **buf)
 
 /* Get the next property of a package. */
 int
-OF_nextprop(phandle_t package, char *previous, char *buf)
+OF_nextprop(phandle_t package, const char *previous, char *buf, size_t size)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t package;
-		cell_t previous;
-		cell_t buf;
-		cell_t flag;
-	} args = {
-		(cell_t)"nextprop",
-		3,
-		1,
-	};
-
-	args.package = package;
-	args.previous = (cell_t)previous;
-	args.buf = (cell_t)buf;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.flag);
+	return (OFW_NEXTPROP(ofw_obj, package, previous, buf, size));
 }
 
 /* Set the value of a property of a package. */
-/* XXX Has a bug on FirePower */
 int
-OF_setprop(phandle_t package, char *propname, void *buf, int len)
+OF_setprop(phandle_t package, const char *propname, const void *buf, size_t len)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t package;
-		cell_t propname;
-		cell_t buf;
-		cell_t len;
-		cell_t size;
-	} args = {
-		(cell_t)"setprop",
-		4,
-		1,
-	};
-
-	args.package = package;
-	args.propname = (cell_t)propname;
-	args.buf = (cell_t)buf;
-	args.len = len;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.size);
+	return (OFW_SETPROP(ofw_obj, package, propname, buf,len));
 }
 
 /* Convert a device specifier to a fully qualified pathname. */
-int
-OF_canon(const char *device, char *buf, int len)
+ssize_t
+OF_canon(const char *device, char *buf, size_t len)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t device;
-		cell_t buf;
-		cell_t len;
-		cell_t size;
-	} args = {
-		(cell_t)"canon",
-		3,
-		1,
-	};
-
-	args.device = (cell_t)device;
-	args.buf = (cell_t)buf;
-	args.len = len;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.size);
+	return (OFW_CANON(ofw_obj, device, buf, len));
 }
 
 /* Return a package handle for the specified device. */
 phandle_t
 OF_finddevice(const char *device)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t device;
-		cell_t package;
-	} args = {
-		(cell_t)"finddevice",
-		1,
-		1,
-	};
-
-	args.device = (cell_t)device;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.package);
+	return (OFW_FINDDEVICE(ofw_obj, device));
 }
 
 /* Return the fully qualified pathname corresponding to an instance. */
-int
-OF_instance_to_path(ihandle_t instance, char *buf, int len)
+ssize_t
+OF_instance_to_path(ihandle_t instance, char *buf, size_t len)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t instance;
-		cell_t buf;
-		cell_t len;
-		cell_t size;
-	} args = {
-		(cell_t)"instance-to-path",
-		3,
-		1,
-	};
-
-	args.instance = instance;
-	args.buf = (cell_t)buf;
-	args.len = len;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.size);
+	return (OFW_INSTANCE_TO_PATH(ofw_obj, instance, buf, len));
 }
 
 /* Return the fully qualified pathname corresponding to a package. */
-int
-OF_package_to_path(phandle_t package, char *buf, int len)
+ssize_t
+OF_package_to_path(phandle_t package, char *buf, size_t len)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t package;
-		cell_t buf;
-		cell_t len;
-		cell_t size;
-	} args = {
-		(cell_t)"package-to-path",
-		3,
-		1,
-	};
-
-	args.package = package;
-	args.buf = (cell_t)buf;
-	args.len = len;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.size);
+	return (OFW_PACKAGE_TO_PATH(ofw_obj, package, buf, len));
 }
 
 /*  Call the method in the scope of a given instance. */
 int
-OF_call_method(char *method, ihandle_t instance, int nargs, int nreturns, ...)
+OF_call_method(const char *method, ihandle_t instance, int nargs, int nreturns,
+    ...)
 {
 	va_list ap;
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t method;
-		cell_t instance;
-		cell_t args_n_results[12];
-	} args = {
-		(cell_t)"call-method",
-		2,
-		1,
-	};
-	cell_t *cp;
-	int n;
+	unsigned long args_n_results[12];
+	int n, status;
 
 	if (nargs > 6)
 		return (-1);
-	args.nargs = nargs + 2;
-	args.nreturns = nreturns + 1;
-	args.method = (cell_t)method;
-	args.instance = instance;
 	va_start(ap, nreturns);
-	for (cp = args.args_n_results + (n = nargs); --n >= 0;)
-		*--cp = va_arg(ap, cell_t);
-	if (openfirmware(&args) == -1)
-		return (-1);
-	if (args.args_n_results[nargs])
-		return (args.args_n_results[nargs]);
-	for (cp = args.args_n_results + nargs + (n = args.nreturns); --n > 0;)
-		*va_arg(ap, cell_t *) = *--cp;
+	for (n = 0; n < nargs; n++)
+		args_n_results[n] = va_arg(ap, unsigned long);
+
+	status = OFW_CALL_METHOD(ofw_obj, instance, method, nargs, nreturns,
+	    args_n_results);
+
+	if (status != 0)
+		return (status);
+
+	for (; n < nargs + nreturns; n++)
+		*va_arg(ap, unsigned long *) = args_n_results[n];
 	va_end(ap);
 	return (0);
 }
@@ -542,122 +318,37 @@ OF_call_method(char *method, ihandle_t instance, int nargs, int nreturns, ...)
 
 /* Open an instance for a device. */
 ihandle_t
-OF_open(char *device)
+OF_open(const char *device)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t device;
-		cell_t instance;
-	} args = {
-		(cell_t)"open",
-		1,
-		1,
-	};
-
-	args.device = (cell_t)device;
-	if (openfirmware(&args) == -1 || args.instance == 0) {
-		return (-1);
-	}
-	return (args.instance);
+	return (OFW_OPEN(ofw_obj, device));
 }
 
 /* Close an instance. */
 void
 OF_close(ihandle_t instance)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t instance;
-	} args = {
-		(cell_t)"close",
-		1,
-	};
-
-	args.instance = instance;
-	openfirmware(&args);
+	OFW_CLOSE(ofw_obj, instance);
 }
 
 /* Read from an instance. */
-int
-OF_read(ihandle_t instance, void *addr, int len)
+ssize_t
+OF_read(ihandle_t instance, void *addr, size_t len)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t instance;
-		cell_t addr;
-		cell_t len;
-		cell_t actual;
-	} args = {
-		(cell_t)"read",
-		3,
-		1,
-	};
-
-	args.instance = instance;
-	args.addr = (cell_t)addr;
-	args.len = len;
-	if (openfirmware(&args) == -1)
-		return (-1);
-
-	return (args.actual);
+	return (OFW_READ(ofw_obj, instance, addr, len));
 }
 
 /* Write to an instance. */
-int
-OF_write(ihandle_t instance, void *addr, int len)
+ssize_t
+OF_write(ihandle_t instance, const void *addr, size_t len)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t instance;
-		cell_t addr;
-		cell_t len;
-		cell_t actual;
-	} args = {
-		(cell_t)"write",
-		3,
-		1,
-	};
-
-	args.instance = instance;
-	args.addr = (cell_t)addr;
-	args.len = len;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.actual);
+	return (OFW_WRITE(ofw_obj, instance, addr, len));
 }
 
 /* Seek to a position. */
 int
-OF_seek(ihandle_t instance, u_int64_t pos)
+OF_seek(ihandle_t instance, uint64_t pos)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t instance;
-		cell_t poshi;
-		cell_t poslo;
-		cell_t status;
-	} args = {
-		(cell_t)"seek",
-		3,
-		1,
-	};
-
-	args.instance = instance;
-	args.poshi = pos >> 32;
-	args.poslo = pos;
-	if (openfirmware(&args) == -1)
-		return (-1);
-	return (args.status);
+	return (OFW_SEEK(ofw_obj, instance, pos));
 }
 
 /*
@@ -666,145 +357,37 @@ OF_seek(ihandle_t instance, u_int64_t pos)
 
 /* Claim an area of memory. */
 void *
-OF_claim(void *virt, u_int size, u_int align)
+OF_claim(void *virt, size_t size, u_int align)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t virt;
-		cell_t size;
-		cell_t align;
-		cell_t baseaddr;
-	} args = {
-		(cell_t)"claim",
-		3,
-		1,
-	};
-
-	args.virt = (cell_t)virt;
-	args.size = size;
-	args.align = align;
-	if (openfirmware(&args) == -1)
-		return ((void *)-1);
-	return ((void *)args.baseaddr);
+	return (OFW_CLAIM(ofw_obj, virt, size, align));
 }
 
 /* Release an area of memory. */
 void
-OF_release(void *virt, u_int size)
+OF_release(void *virt, size_t size)
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t virt;
-		cell_t size;
-	} args = {
-		(cell_t)"release",
-		2,
-	};
-
-	args.virt = (cell_t)virt;
-	args.size = size;
-	openfirmware(&args);
+	OFW_RELEASE(ofw_obj, virt, size);
 }
 
 /*
  * Control transfer functions
  */
 
-/* Reset the system and call "boot <bootspec>". */
-void
-OF_boot(char *bootspec)
-{
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t bootspec;
-	} args = {
-		(cell_t)"boot",
-		1,
-	};
-
-	args.bootspec = (cell_t)bootspec;
-	openfirmware(&args);
-	for (;;)			/* just in case */
-		;
-}
-
 /* Suspend and drop back to the Open Firmware interface. */
 void
 OF_enter()
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-	} args = {
-		(cell_t)"enter",
-	};
-
-	openfirmware(&args);
-	/* We may come back. */
+	OFW_ENTER(ofw_obj);
 }
 
 /* Shut down and drop back to the Open Firmware interface. */
 void
 OF_exit()
 {
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-	} args = {
-		(cell_t)"exit",
-	};
-
-	openfirmware(&args);
+	/* Should not return */
+	OFW_EXIT(ofw_obj);
+
 	for (;;)			/* just in case */
 		;
 }
 
-/* Free <size> bytes starting at <virt>, then call <entry> with <arg>. */
-#if 0
-void
-OF_chain(void *virt, u_int size, void (*entry)(), void *arg, u_int len)
-{
-	static struct {
-		cell_t name;
-		cell_t nargs;
-		cell_t nreturns;
-		cell_t virt;
-		cell_t size;
-		cell_t entry;
-		cell_t arg;
-		cell_t len;
-	} args = {
-		(cell_t)"chain",
-		5,
-	};
-
-	args.virt = (cell_t)virt;
-	args.size = size;
-	args.entry = (cell_t)entry;
-	args.arg = (cell_t)arg;
-	args.len = len;
-	openfirmware(&args);
-}
-#else
-void
-OF_chain(void *virt, u_int size,
-    void (*entry)(void *, u_int, void *, void *, u_int), void *arg, u_int len)
-{
-	/*
-	 * This is a REALLY dirty hack till the firmware gets this going
-	 */
-#if 0
-	if (size > 0)
-		OF_release(virt, size);
-#endif
-	entry(0, 0, openfirmware, arg, len);
-}
-#endif
diff --git a/sys/dev/ofw/openfirm.h b/sys/dev/ofw/openfirm.h
index a676fc56..08a0544 100644
--- a/sys/dev/ofw/openfirm.h
+++ b/sys/dev/ofw/openfirm.h
@@ -60,84 +60,82 @@
 #ifndef _OPENFIRM_H_
 #define _OPENFIRM_H_
 
+#include <sys/types.h>
+
 /*
  * Prototypes for Open Firmware Interface Routines
  */
 
-typedef unsigned long cell_t;
-
-typedef	unsigned int	ihandle_t;
-typedef unsigned int	phandle_t;
+typedef	uint32_t	ihandle_t;
+typedef uint32_t	phandle_t;
+typedef uint32_t	pcell_t;
 
 #ifdef _KERNEL
-#include <sys/cdefs.h>
-#include <sys/types.h>
 #include <sys/malloc.h>
 
+#include <machine/ofw_machdep.h>
+
 MALLOC_DECLARE(M_OFWPROP);
 
 /*
- * Other than in Open Firmware calls, the size of a bus cell seems to be
- * always the same.
+ * Open Firmware interface initialization. OF_install installs the named
+ * interface as the Open Firmware access mechanism, OF_init initializes it.
  */
-typedef u_int32_t pcell_t;
 
-/*
- * Stuff that is used by the Open Firmware code.
- */
-void	set_openfirm_callback(int (*)(void *));
-int	openfirmware(void *);
+boolean_t	OF_install(char *name, int prio);
+void		OF_init(void *cookie);
 
 /*
- * This isn't actually an Open Firmware function, but it seemed like the right
- * place for it to go.
+ * Known Open Firmware interface names
  */
-void		OF_init(int (*openfirm)(void *));
+
+#define	OFW_STD_DIRECT	"ofw_std"	/* Standard OF interface */
+#define	OFW_STD_REAL	"ofw_real"	/* Real-mode OF interface */
+#define	OFW_FDT		"ofw_fdt"	/* Flattened Device Tree */
 
 /* Generic functions */
-int		OF_test(char *);
+int		OF_test(const char *);
 void		OF_printf(const char *, ...);
 
 /* Device tree functions */
-phandle_t	OF_peer(phandle_t);
-phandle_t	OF_child(phandle_t);
-phandle_t	OF_parent(phandle_t);
-phandle_t	OF_instance_to_package(ihandle_t);
-int		OF_getproplen(phandle_t, char *);
-int		OF_getprop(phandle_t, char *, void *, int);
-int		OF_getprop_alloc(phandle_t package, char *propname, int elsz,
-    void **buf);
-int		OF_nextprop(phandle_t, char *, char *);
-int		OF_setprop(phandle_t, char *, void *, int);
-int		OF_canon(const char *, char *, int);
-phandle_t	OF_finddevice(const char *);
-int		OF_instance_to_path(ihandle_t, char *, int);
-int		OF_package_to_path(phandle_t, char *, int);
-int		OF_call_method(char *, ihandle_t, int, int, ...);
+phandle_t	OF_peer(phandle_t node);
+phandle_t	OF_child(phandle_t node);
+phandle_t	OF_parent(phandle_t node);
+ssize_t		OF_getproplen(phandle_t node, const char *propname);
+ssize_t		OF_getprop(phandle_t node, const char *propname, void *buf,
+		    size_t len);
+ssize_t		OF_getprop_alloc(phandle_t node, const char *propname,
+		    int elsz, void **buf);
+int		OF_nextprop(phandle_t node, const char *propname, char *buf,
+		    size_t len);
+int		OF_setprop(phandle_t node, const char *name, const void *buf,
+		    size_t len);
+ssize_t		OF_canon(const char *path, char *buf, size_t len);
+phandle_t	OF_finddevice(const char *path);
+ssize_t		OF_package_to_path(phandle_t node, char *buf, size_t len);
 
 /* Device I/O functions */
-ihandle_t	OF_open(char *);
-void		OF_close(ihandle_t);
-int		OF_read(ihandle_t, void *, int);
-int		OF_write(ihandle_t, void *, int);
-int		OF_seek(ihandle_t, u_quad_t);
+ihandle_t	OF_open(const char *path);
+void		OF_close(ihandle_t instance);
+ssize_t		OF_read(ihandle_t instance, void *buf, size_t len);
+ssize_t		OF_write(ihandle_t instance, const void *buf, size_t len);
+int		OF_seek(ihandle_t instance, uint64_t where);
+
+phandle_t	OF_instance_to_package(ihandle_t instance);
+ssize_t		OF_instance_to_path(ihandle_t instance, char *buf, size_t len);
+int		OF_call_method(const char *method, ihandle_t instance,
+		    int nargs, int nreturns, ...);
 
 /* Memory functions */
-void 		*OF_claim(void *, u_int, u_int);
-void		OF_release(void *, u_int);
+void 		*OF_claim(void *virtrequest, size_t size, u_int align);
+void		OF_release(void *virt, size_t size);
 
 /* Control transfer functions */
-void		OF_boot(char *);
 void		OF_enter(void);
 void		OF_exit(void) __attribute__((noreturn));
-void		OF_chain(void *, u_int,
-    void (*)(void *, u_int, void *, void *, u_int), void *, u_int);
 
 /* User interface functions */
-int		OF_interpret(char *, int, ...);
-
-/* Time function */
-int		OF_milliseconds(void);
+int		OF_interpret(const char *cmd, int nreturns, ...);
 
 #endif /* _KERNEL */
 #endif /* _OPENFIRM_H_ */
diff --git a/sys/dev/ofw/openfirmio.c b/sys/dev/ofw/openfirmio.c
index 47f2517..d042f02 100644
--- a/sys/dev/ofw/openfirmio.c
+++ b/sys/dev/ofw/openfirmio.c
@@ -221,7 +221,7 @@ openfirm_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags,
 			if (error)
 				break;
 		}
-		ok = OF_nextprop(node, name, newname);
+		ok = OF_nextprop(node, name, newname, sizeof(newname));
 		if (ok == 0) {
 			error = ENOENT;
 			break;
diff --git a/sys/dev/ofw/openpromio.c b/sys/dev/ofw/openpromio.c
index cb7343f..8ba6d3a 100644
--- a/sys/dev/ofw/openpromio.c
+++ b/sys/dev/ofw/openpromio.c
@@ -174,7 +174,7 @@ openprom_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags,
 			error = OF_getprop(node, prop, buf, proplen);
 			break;
 		case OPROMNXTPROP:
-			error = OF_nextprop(node, prop, buf);
+			error = OF_nextprop(node, prop, buf, OPROMMAXPARAM);
 			proplen = strlen(buf);
 			break;
 		}