Overhaul the markup.

OK'ed by:	imp
Approved by:	re (blanket)

1 files changed, 559 insertions, 438 deletions

diff --git a/share/man/man9/bus_space.9 b/share/man/man9/bus_space.9
index 3b61c54..c51a6f8 100644
--- a/share/man/man9/bus_space.9
+++ b/share/man/man9/bus_space.9
@@ -1,5 +1,5 @@
 .\" $NetBSD: bus_space.9,v 1.9 1999/03/06 22:09:29 mycroft Exp $
-.\" $FreeBSD$
+.\"
 .\" Copyright (c) 2005 M. Warner Losh.  All Rights Reserved.
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
@@ -24,10 +24,10 @@
 .\"
 .\" Copyright (c) 1997 The NetBSD Foundation, Inc.
 .\" All rights reserved.
-.\" 
+.\"
 .\" This code is derived from software contributed to The NetBSD Foundation
 .\" by Christopher G. Demetriou.
-.\" 
+.\"
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
 .\" are met:
@@ -43,7 +43,7 @@
 .\" 4. Neither the name of The NetBSD Foundation nor the names of its
 .\"    contributors may be used to endorse or promote products derived
 .\"    from this software without specific prior written permission.
-.\" 
+.\"
 .\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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
@@ -56,6 +56,8 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
+.\" $FreeBSD$
+.\"
 .Dd June 13, 2005
 .Dt BUS_SPACE 9
 .Os
@@ -102,18 +104,23 @@
 .Nm bus_space_write_region_2 ,
 .Nm bus_space_write_region_4 ,
 .Nm bus_space_write_region_8
-.Nd bus space manipulation functions
+.Nd "bus space manipulation functions"
 .Sh SYNOPSIS
-.Fd #include <machine/bus.h>
+.In machine/bus.h
 .Ft int
-.Fn bus_space_map "bus_space_tag_t space" "bus_addr_t address" \
-"bus_size_t size" "int flags" "bus_space_handle_t *handlep"
+.Fo bus_space_map
+.Fa "bus_space_tag_t space" "bus_addr_t address"
+.Fa "bus_size_t size" "int flags" "bus_space_handle_t *handlep"
+.Fc
 .Ft void
-.Fn bus_space_unmap "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t size"
+.Fo bus_space_unmap
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle" "bus_size_t size"
+.Fc
 .Ft int
-.Fn bus_space_subregion "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t offset" "bus_size_t size" "bus_space_handle_t *nhandlep"
+.Fo bus_space_subregion
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle"
+.Fa "bus_size_t offset" "bus_size_t size" "bus_space_handle_t *nhandlep"
+.Fc
 .Ft int
 .Fo bus_space_alloc
 .Fa "bus_space_tag_t space" "bus_addr_t reg_start" "bus_addr_t reg_end"
@@ -121,167 +128,240 @@
 .Fa "int flags" "bus_addr_t *addrp" "bus_space_handle_t *handlep"
 .Fc
 .Ft void
-.Fn bus_space_free "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t size"
+.Fo bus_space_free
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle" "bus_size_t size"
+.Fc
 .Ft u_int8_t
-.Fn bus_space_read_1 "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t offset"
+.Fo bus_space_read_1
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle" "bus_size_t offset"
+.Fc
 .Ft u_int16_t
-.Fn bus_space_read_2 "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t offset"
+.Fo bus_space_read_2
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle" "bus_size_t offset"
+.Fc
 .Ft u_int32_t
-.Fn bus_space_read_4 "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t offset"
+.Fo bus_space_read_4
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle" "bus_size_t offset"
+.Fc
 .Ft u_int64_t
-.Fn bus_space_read_8 "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t offset"
+.Fo bus_space_read_8
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle" "bus_size_t offset"
+.Fc
 .Ft void
-.Fn bus_space_write_1 "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t offset" "u_int8_t value"
+.Fo bus_space_write_1
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle"
+.Fa "bus_size_t offset" "u_int8_t value"
+.Fc
 .Ft void
-.Fn bus_space_write_2 "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t offset" "u_int16_t value"
+.Fo bus_space_write_2
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle"
+.Fa "bus_size_t offset" "u_int16_t value"
+.Fc
 .Ft void
-.Fn bus_space_write_4 "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t offset" "u_int32_t value"
+.Fo bus_space_write_4
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle"
+.Fa "bus_size_t offset" "u_int32_t value"
+.Fc
 .Ft void
-.Fn bus_space_write_8 "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t offset" "u_int64_t value"
+.Fo bus_space_write_8
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle"
+.Fa "bus_size_t offset" "u_int64_t value"
+.Fc
 .Ft void
-.Fn bus_space_barrier "bus_space_tag_t space" "bus_space_handle_t handle" \
-"bus_size_t offset" "bus_size_t length" "int flags"
+.Fo bus_space_barrier
+.Fa "bus_space_tag_t space" "bus_space_handle_t handle"
+.Fa "bus_size_t offset" "bus_size_t length" "int flags"
+.Fc
 .Ft void
-.Fn bus_space_read_region_1 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int8_t *datap" \
-"bus_size_t count"
+.Fo bus_space_read_region_1
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int8_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_read_region_2 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int16_t *datap" \
-"bus_size_t count"
+.Fo bus_space_read_region_2
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int16_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_read_region_4 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int32_t *datap" \
-"bus_size_t count"
+.Fo bus_space_read_region_4
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int32_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_read_region_8 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int64_t *datap" \
-"bus_size_t count"
+.Fo bus_space_read_region_8
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int64_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_write_region_1 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int8_t *datap" \
-"bus_size_t count"
+.Fo bus_space_write_region_1
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int8_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_write_region_2 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int16_t *datap" \
-"bus_size_t count"
+.Fo bus_space_write_region_2
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int16_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_write_region_4 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int32_t *datap" \
-"bus_size_t count"
+.Fo bus_space_write_region_4
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int32_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_write_region_8 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int64_t *datap" \
-"bus_size_t count"
+.Fo bus_space_write_region_8
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int64_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_copy_region_1 "bus_space_tag_t space" \
-"bus_space_handle_t srchandle" "bus_size_t srcoffset" \
-"bus_space_handle_t dsthandle" "bus_size_t dstoffset" "bus_size_t count"
+.Fo bus_space_copy_region_1
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t srchandle" "bus_size_t srcoffset"
+.Fa "bus_space_handle_t dsthandle" "bus_size_t dstoffset" "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_copy_region_2 "bus_space_tag_t space" \
-"bus_space_handle_t srchandle" "bus_size_t srcoffset" \
-"bus_space_handle_t dsthandle" "bus_size_t dstoffset" "bus_size_t count"
+.Fo bus_space_copy_region_2
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t srchandle" "bus_size_t srcoffset"
+.Fa "bus_space_handle_t dsthandle" "bus_size_t dstoffset" "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_copy_region_4 "bus_space_tag_t space" \
-"bus_space_handle_t srchandle" "bus_size_t srcoffset" \
-"bus_space_handle_t dsthandle" "bus_size_t dstoffset" "bus_size_t count"
+.Fo bus_space_copy_region_4
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t srchandle" "bus_size_t srcoffset"
+.Fa "bus_space_handle_t dsthandle" "bus_size_t dstoffset" "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_copy_region_8 "bus_space_tag_t space" \
-"bus_space_handle_t srchandle" "bus_size_t srcoffset" \
-"bus_space_handle_t dsthandle" "bus_size_t dstoffset" "bus_size_t count"
+.Fo bus_space_copy_region_8
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t srchandle" "bus_size_t srcoffset"
+.Fa "bus_space_handle_t dsthandle" "bus_size_t dstoffset" "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_set_region_1 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int8_t value" \
-"bus_size_t count"
+.Fo bus_space_set_region_1
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int8_t value"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_set_region_2 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int16_t value" \
-"bus_size_t count"
+.Fo bus_space_set_region_2
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int16_t value"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_set_region_4 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int32_t value" \
-"bus_size_t count"
+.Fo bus_space_set_region_4
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int32_t value"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_set_region_8 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int64_t value" \
-"bus_size_t count"
+.Fo bus_space_set_region_8
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int64_t value"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_read_multi_1 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int8_t *datap" \
-"bus_size_t count"
+.Fo bus_space_read_multi_1
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int8_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_read_multi_2 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int16_t *datap" \
-"bus_size_t count"
+.Fo bus_space_read_multi_2
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int16_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_read_multi_4 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int32_t *datap" \
-"bus_size_t count"
+.Fo bus_space_read_multi_4
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int32_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_read_multi_8 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int64_t *datap" \
-"bus_size_t count"
+.Fo bus_space_read_multi_8
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int64_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_write_multi_1 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int8_t *datap" \
-"bus_size_t count"
+.Fo bus_space_write_multi_1
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int8_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_write_multi_2 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int16_t *datap" \
-"bus_size_t count"
+.Fo bus_space_write_multi_2
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int16_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_write_multi_4 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int32_t *datap" \
-"bus_size_t count"
+.Fo bus_space_write_multi_4
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int32_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_write_multi_8 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int64_t *datap" \
-"bus_size_t count"
+.Fo bus_space_write_multi_8
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int64_t *datap"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_set_multi_1 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int8_t value" \
-"bus_size_t count"
+.Fo bus_space_set_multi_1
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int8_t value"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_set_multi_2 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int16_t value" \
-"bus_size_t count"
+.Fo bus_space_set_multi_2
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int16_t value"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_set_multi_4 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int32_t value" \
-"bus_size_t count"
+.Fo bus_space_set_multi_4
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int32_t value"
+.Fa "bus_size_t count"
+.Fc
 .Ft void
-.Fn bus_space_set_multi_8 "bus_space_tag_t space" \
-"bus_space_handle_t handle" "bus_size_t offset" "u_int64_t value" \
-"bus_size_t count"
+.Fo bus_space_set_multi_8
+.Fa "bus_space_tag_t space"
+.Fa "bus_space_handle_t handle" "bus_size_t offset" "u_int64_t value"
+.Fa "bus_size_t count"
+.Fc
 .Sh DESCRIPTION
-.Pp
 The
 .Nm
 functions exist to allow device drivers
-machine-independent access to bus memory and register areas.  All of the
+machine-independent access to bus memory and register areas.
+All of the
 functions and types described in this document can be used by including
-the 
-.Pa Aq machine/bus.h
+the
+.In machine/bus.h
 header file.
 .Pp
 Many common devices are used on multiple architectures, but are accessed
 differently on each because of architectural constraints.
-For instance, a device which is mapped in one systems's I/O space may be
-mapped in memory space on a second system.  On a third system, architectural
-limitations might change the way registers need to be accessed (e.g.
+For instance, a device which is mapped in one system's I/O space may be
+mapped in memory space on a second system.
+On a third system, architectural
+limitations might change the way registers need to be accessed (e.g.\&
 creating a non-linear register space).
 In some cases, a single
 driver may need to access the same type of device in multiple ways in a
-single system or architecture.  The goal of the
+single system or architecture.
+The goal of the
 .Nm
 functions is to allow a single driver source file to manipulate a set
 of devices on different system architectures, and to allow a single driver
@@ -290,35 +370,43 @@ single architecture.
 .Pp
 Not all busses have to implement all functions described in this
 document, though that is encouraged if the operations are logically
-supported by the bus.  Unimplemented functions should cause
+supported by the bus.
+Unimplemented functions should cause
 compile-time errors if possible.
 .Pp
 All of the interface definitions described in this document are shown as
 function prototypes and discussed as if they were required to be
-functions.  Implementations are encouraged to implement prototyped
+functions.
+Implementations are encouraged to implement prototyped
 (type-checked) versions of these interfaces, but may implement them as
-macros if appropriate.  Machine-dependent types, variables, and functions
+macros if appropriate.
+Machine-dependent types, variables, and functions
 should be marked clearly in
-.Pa Aq machine/bus.h
+.In machine/bus.h
 to avoid confusion with the
 machine-independent types and functions, and, if possible, should be
 given names which make the machine-dependence clear.
 .Sh CONCEPTS AND GUIDELINES
-.Pp
 Bus spaces are described by bus space tags, which can be created only by
-machine-dependent code.  A given machine may have several different types
-of bus space (e.g. memory space and I/O space), and thus may provide
+machine-dependent code.
+A given machine may have several different types
+of bus space (e.g.\& memory space and I/O space), and thus may provide
 multiple different bus space tags.
 Individual busses or devices on a machine may use more than one bus space
-tag.  For instance, ISA devices are
-given an ISA memory space tag and an ISA I/O space tag.  Architectures
+tag.
+For instance, ISA devices are
+given an ISA memory space tag and an ISA I/O space tag.
+Architectures
 may have several different tags which represent the same type of
 space, for instance because of multiple different host bus interface
 chipsets.
 .Pp
-A range in bus space is described by a bus address and a bus size.  The
-bus address describes the start of the range in bus space.  The bus
-size describes the size of the range in bytes.  Busses which are not byte
+A range in bus space is described by a bus address and a bus size.
+The
+bus address describes the start of the range in bus space.
+The bus
+size describes the size of the range in bytes.
+Busses which are not byte
 addressable may require use of bus space ranges with appropriately
 aligned addresses and properly rounded sizes.
 .Pp
@@ -334,146 +422,157 @@ argument, at least one handle argument, and at least one offset argument
 (a bus size).
 The bus space tag specifies the space, each handle specifies a region in
 the space, and each offset specifies the offset into the region of the
-actual location(s) to be accessed.  Offsets are given in bytes, though busses
-may impose alignment constraints.  The offset used to access data
+actual location(s) to be accessed.
+Offsets are given in bytes, though busses
+may impose alignment constraints.
+The offset used to access data
 relative to a given handle must be such that all of the data being
-accessed is in the mapped region that the handle describes.  Trying to
+accessed is in the mapped region that the handle describes.
+Trying to
 access data outside that region is an error.
 .Pp
 Because some architectures' memory systems use buffering to improve
 memory and device access performance, there is a mechanism which can be
 used to create
 .Dq barriers
-in the bus space read and write stream.  There
-are three types of barriers: read, write, and read/write.  All reads
+in the bus space read and write stream.
+There
+are three types of barriers: read, write, and read/write.
+All reads
 started to the region before a read barrier must complete before any reads
-after the read barrier are started.  (The analogous requirement is true for
-write barriers.)  Read/write barriers force all reads and writes started
+after the read barrier are started.
+(The analogous requirement is true for
+write barriers.)
+Read/write barriers force all reads and writes started
 before the barrier to complete before any reads or writes after the
-barrier are started.  Correctly-written drivers will include all
+barrier are started.
+Correctly-written drivers will include all
 appropriate barriers, and assume only the read/write ordering imposed by
 the barrier operations.
 .Pp
 People trying to write portable drivers with the
 .Nm
 functions should
-try to make minimal assumptions about what the system allows.  In particular,
+try to make minimal assumptions about what the system allows.
+In particular,
 they should expect that the system requires bus space addresses being
-accessed to be naturally aligned (i.e. base address of handle added to
+accessed to be naturally aligned (i.e., base address of handle added to
 offset is a multiple of the access size), and that the system does
-alignment checking on pointers (i.e. pointer to objects being read and
+alignment checking on pointers (i.e., pointer to objects being read and
 written must point to properly-aligned data).
 .Pp
 The descriptions of the
 .Nm
 functions given below all assume that
-they are called with proper arguments.  If called with invalid arguments
-or arguments that are out of range (e.g. trying to access data outside of
+they are called with proper arguments.
+If called with invalid arguments
+or arguments that are out of range (e.g.\& trying to access data outside of
 the region mapped when a given handle was created), undefined behaviour
-results.  In that case, they may cause the
+results.
+In that case, they may cause the
 system to halt, either intentionally (via panic) or unintentionally (by
 causing a fatal trap of by some other means) or may cause improper
-operation which is not immediately fatal.  Functions which return
-void or which return data read from bus space (i.e., functions which
-don't obviously return an error code) do not fail.  They could only fail
+operation which is not immediately fatal.
+Functions which return
+.Ft void
+or which return data read from bus space (i.e., functions which
+do not obviously return an error code) do not fail.
+They could only fail
 if given invalid arguments, and in that case their behaviour is undefined.
-.Pp
 .Sh TYPES
 Several types are defined in
-.Pa Aq machine/bus.h
+.In machine/bus.h
 to facilitate use of the
 .Nm
 functions by drivers.
-.Pp
-.Bl -ohang -compact
-.It Fa bus_addr_t
-.Pp
+.Ss Vt bus_addr_t
 The
-.Fa bus_addr_t
-type is used to describe bus addresses.  It must be an
+.Vt bus_addr_t
+type is used to describe bus addresses.
+It must be an
 unsigned integral type
-capable of holding the largest bus address usable by the architecture.  This
+capable of holding the largest bus address usable by the architecture.
+This
 type is primarily used when mapping and unmapping bus space.
-.Pp
-.It Fa bus_size_t
-.Pp
+.Ss Vt bus_size_t
 The
-.Fa bus_size_t
-type is used to describe sizes of ranges in bus space.  It must be an
+.Vt bus_size_t
+type is used to describe sizes of ranges in bus space.
+It must be an
 unsigned integral type capable of holding the size of the largest bus
-address range usable on the architecture.  This type is used by virtually all
+address range usable on the architecture.
+This type is used by virtually all
 of the
 .Nm
 functions, describing sizes when mapping regions and
 offsets into regions when performing space access operations.
-.Pp
-.It Fa bus_space_tag_t
-.Pp
+.Ss Vt bus_space_tag_t
 The
-.Fa bus_space_tag_t
-type is used to describe a particular bus space on a machine.  Its
+.Vt bus_space_tag_t
+type is used to describe a particular bus space on a machine.
+Its
 contents are machine-dependent and should be considered opaque by
-machine-independent code.  This type is used by all
+machine-independent code.
+This type is used by all
 .Nm
-functions to name the space on which they're operating.
-.Pp
-.It Fa bus_space_handle_t
-.Pp
+functions to name the space on which they are operating.
+.Ss Vt bus_space_handle_t
 The
-.Fa bus_space_handle_t
-type is used to describe a mapping of a range of bus space.  Its
+.Vt bus_space_handle_t
+type is used to describe a mapping of a range of bus space.
+Its
 contents are machine-dependent and should be considered opaque by
-machine-independent code.  This type is used when performing bus space
+machine-independent code.
+This type is used when performing bus space
 access operations.
-.El
-.Pp
 .Sh MAPPING AND UNMAPPING BUS SPACE
-.Pp
 This section is specific to the
-.Nx 
+.Nx
 version of these functions and may or may not apply to the
-.Fx 
+.Fx
 version.
 .Pp
 Bus space must be mapped before it can be used, and should be
-unmapped when it is no longer needed.  The
+unmapped when it is no longer needed.
+The
 .Fn bus_space_map
 and
 .Fn bus_space_unmap
 functions provide these capabilities.
 .Pp
 Some drivers need to be able to pass a subregion of already-mapped bus
-space to another driver or module within a driver.  The
+space to another driver or module within a driver.
+The
 .Fn bus_space_subregion
 function allows such subregions to be created.
-.Pp
-.Bl -ohang -compact
-.It Fn bus_space_map "space" "address" "size" "flags" "handlep"
-.Pp
+.Ss Fn bus_space_map space address size flags handlep
 The
 .Fn bus_space_map
 function maps the region of bus space named by the
-.Fa space ,
-.Fa address ,
+.Fa space , address ,
 and
 .Fa size
-arguments.  If successful, it returns zero
-and fills in the bus space handle pointed to by 
+arguments.
+If successful, it returns zero
+and fills in the bus space handle pointed to by
 .Fa handlep
 with the handle
-that can be used to access the mapped region.  If unsuccessful,
+that can be used to access the mapped region.
+If unsuccessful,
 it will return non-zero and leave the bus space handle pointed
-to by 
+to by
 .Fa handlep
 in an undefined state.
 .Pp
 The
 .Fa flags
-argument controls how the space is to be mapped.  Supported flags include:
-.Bl -tag -width BUS_SPACE_MAP_CACHEABLE -offset indent
+argument controls how the space is to be mapped.
+Supported flags include:
+.Bl -tag -width ".Dv BUS_SPACE_MAP_CACHEABLE"
 .It Dv BUS_SPACE_MAP_CACHEABLE
 Try to map the space so that accesses can be cached and/or
-prefetched by the system.  If this flag is not specified, the
+prefetched by the system.
+If this flag is not specified, the
 implementation should map the space so that it will not be cached or
 prefetched.
 .Pp
@@ -481,19 +580,22 @@ This flag must have a value of 1 on all implementations for backward
 compatibility.
 .It Dv BUS_SPACE_MAP_LINEAR
 Try to map the space so that its contents can be accessed linearly via
-normal memory access methods (e.g. pointer dereferencing and structure
+normal memory access methods (e.g.\& pointer dereferencing and structure
 accesses).
 This is useful when software wants to do direct access to a memory
-device, e.g. a frame buffer.  If this flag is specified and linear
+device, e.g.\& a frame buffer.
+If this flag is specified and linear
 mapping is not possible, the
 .Fn bus_space_map
-call should fail.  If this
+call should fail.
+If this
 flag is not specified, the system may map the space in whatever way is
 most convenient.
 .El
 .Pp
 Not all combinations of flags make sense or are supported with all
-spaces.  For instance, 
+spaces.
+For instance,
 .Dv BUS_SPACE_MAP_CACHEABLE
 may be meaningless when
 used on many systems' I/O port spaces, and on some systems
@@ -502,30 +604,33 @@ without
 .Dv BUS_SPACE_MAP_CACHEABLE
 may never work.
 When the system hardware or firmware provides hints as to how spaces should be
-mapped (e.g. the PCI memory mapping registers' "prefetchable" bit), those
-hints should be followed for maximum compatibility.  On some systems,
-requesting a mapping that cannot be satisfied (e.g. requesting a
+mapped (e.g.\& the PCI memory mapping registers'
+.Dq prefetchable
+bit), those
+hints should be followed for maximum compatibility.
+On some systems,
+requesting a mapping that cannot be satisfied (e.g.\& requesting a
 non-cacheable mapping when the system can only provide a cacheable one)
 will cause the request to fail.
 .Pp
 Some implementations may keep track of use of bus space for some or all
-bus spaces and refuse to allow duplicate allocations.  This is encouraged
+bus spaces and refuse to allow duplicate allocations.
+This is encouraged
 for bus spaces which have no notion of slot-specific space addressing,
 such as ISA and VME, and for spaces which coexist with those spaces
-(e.g. EISA and PCI memory and I/O spaces co-existing with ISA memory and
+(e.g.\& EISA and PCI memory and I/O spaces co-existing with ISA memory and
 I/O spaces).
 .Pp
 Mapped regions may contain areas for which no there is no device on the
-bus.  If space in those areas is accessed, the results are
+bus.
+If space in those areas is accessed, the results are
 bus-dependent.
-.Pp
-.It Fn bus_space_unmap "space" "handle" "size"
-.Pp
+.Ss Fn bus_space_unmap space handle size
 The
 .Fn bus_space_unmap
 function unmaps a region of bus space mapped with
 .Fn bus_space_map .
-When unmapping a region, the 
+When unmapping a region, the
 .Fa size
 specified should be
 the same as the size given to
@@ -535,26 +640,27 @@ when mapping that region.
 After
 .Fn bus_space_unmap
 is called on a handle, that handle is no longer
-valid.  (If copies were made of the handle they are no longer valid,
+valid.
+(If copies were made of the handle they are no longer valid,
 either.)
 .Pp
-This function will never fail.  If it would fail (e.g. because of an
+This function will never fail.
+If it would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case, 
+panic.
+In that case,
 .Fn bus_space_unmap
 will never return.
-.Pp
-.It Fn bus_space_subregion "space" "handle" "offset" "size" "nhandlep"
-.Pp
+.Ss Fn bus_space_subregion space handle offset size nhandlep
 The
 .Fn bus_space_subregion
 function is a convenience function which makes a
 new handle to some subregion of an already-mapped region of bus space.
-The subregion described by the new handle starts at byte offset 
+The subregion described by the new handle starts at byte offset
 .Fa offset
-into the region described by 
+into the region described by
 .Fa handle ,
-with the size give by 
+with the size give by
 .Fa size ,
 and must be wholly contained within the original region.
 .Pp
@@ -567,78 +673,75 @@ If unsuccessful, it returns non-zero and leaves the bus space handle
 pointed to by
 .Fa nhandlep
 in an
-undefined state.  In either case, the handle described by
+undefined state.
+In either case, the handle described by
 .Fa handle
 remains valid and is unmodified.
 .Pp
-When done with a handle created by 
+When done with a handle created by
 .Fn bus_space_subregion ,
 the handle should
-be thrown away.  Under no circumstances should
+be thrown away.
+Under no circumstances should
 .Fn bus_space_unmap
-be used on the handle.  Doing so may confuse any resource management
-being done on the space, and will result in undefined behaviour.  When
+be used on the handle.
+Doing so may confuse any resource management
+being done on the space, and will result in undefined behaviour.
+When
 .Fn bus_space_unmap
 or
 .Fn bus_space_free
 is called on a handle, all subregions of that handle become invalid.
-.El
-.Pp
 .Sh ALLOCATING AND FREEING BUS SPACE
-.Pp
 This section is specific to the
-.Nx 
+.Nx
 version of these functions and may or may not apply to the
-.Fx 
+.Fx
 version.
 .Pp
 Some devices require or allow bus space to be allocated by the operating
-system for device use.  When the devices no longer need the space, the
-operating system should free it for use by other devices.  The
+system for device use.
+When the devices no longer need the space, the
+operating system should free it for use by other devices.
+The
 .Fn bus_space_alloc
 and
 .Fn bus_space_free
 functions provide these capabilities.
-.Pp
-.Bl -ohang -compact
-.It Xo
-.Fo bus_space_alloc
-.Fa "space" "reg_start" "reg_end" "size"
-.Fa "alignment" "boundary" "flags" "addrp" "handlep"
-.Fc
-.Xc
-.Pp
+.Ss Fn bus_space_alloc space reg_start reg_end size alignment boundary \
+flags addrp handlep
 The
 .Fn bus_space_alloc
 function allocates and maps a region of bus space with the size given by
 .Fa size ,
-corresponding to the given constraints.  If successful, it returns
+corresponding to the given constraints.
+If successful, it returns
 zero, fills in the bus address pointed to by
 .Fa addrp
 with the bus space address of the allocated region, and fills in
-the bus space handle pointed to by 
+the bus space handle pointed to by
 .Fa handlep
 with the handle that can be used to access that region.
 If unsuccessful, it returns non-zero and leaves the bus address pointed to by
 .Fa addrp
-and the bus space handle pointed to by 
+and the bus space handle pointed to by
 .Fa handlep
 in an undefined state.
 .Pp
-Constraints on the allocation are given by the 
-.Fa reg_start ,
-.Fa reg_end ,
-.Fa alignment ,
+Constraints on the allocation are given by the
+.Fa reg_start , reg_end , alignment ,
 and
 .Fa boundary
-parameters.  The allocated region will start at or after
+parameters.
+The allocated region will start at or after
 .Fa reg_start
 and end before or at
 .Fa reg_end .
 The
 .Fa alignment
 constraint must be a power of two, and the allocated region will start at
-an address that is an even multiple of that power of two.  The
+an address that is an even multiple of that power of two.
+The
 .Fa boundary
 constraint, if non-zero, ensures that the region is allocated so that
 .Fa "first address in region"
@@ -650,19 +753,18 @@ has the same value as
 .Fa boundary .
 If the constraints cannot be met,
 .Fn bus_space_alloc
-will fail.  It is an error to specify a set of
+will fail.
+It is an error to specify a set of
 constraints that can never be met
-.Po
-for example,
+(for example,
 .Fa size
 greater than
-.Fa boundary
-.Pc .
+.Fa boundary ) .
 .Pp
 The
 .Fa flags
 parameter is the same as the like-named parameter to
-.Fa bus_space_map ,
+.Fn bus_space_map ,
 the same flag values should be used, and they have the
 same meanings.
 .Pp
@@ -672,14 +774,13 @@ should only be freed with
 .Fn bus_space_free .
 Trying to use
 .Fn bus_space_unmap
-on them causes undefined behaviour.  The
+on them causes undefined behaviour.
+The
 .Fn bus_space_subregion
 function can be used on
 handles created by
 .Fn bus_space_alloc .
-.Pp
-.It Fn bus_space_free "space" "handle" "size"
-.Pp
+.Ss Fn bus_space_free space handle size
 The
 .Fn bus_space_free
 function unmaps and frees a region of bus space mapped
@@ -693,41 +794,39 @@ when allocating the region.
 .Pp
 After
 .Fn bus_space_free
-is called on a handle, that handle is no longer valid.  (If copies were
+is called on a handle, that handle is no longer valid.
+(If copies were
 made of the handle, they are no longer valid, either.)
 .Pp
-This function will never fail.  If it would fail (e.g. because of an
+This function will never fail.
+If it would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case,
+panic.
+In that case,
 .Fn bus_space_free
 will never return.
-.El
-.Pp
 .Sh READING AND WRITING SINGLE DATA ITEMS
-.Pp
 The simplest way to access bus space is to read or write a single data
-item.  The
+item.
+The
 .Fn bus_space_read_N
 and
 .Fn bus_space_write_N
 families of functions provide
 the ability to read and write 1, 2, 4, and 8 byte data items on busses
 which support those access sizes.
-.Pp
-.Bl -ohang -compact
-.It Fn bus_space_read_1 "space" "handle" "offset"
-.It Fn bus_space_read_2 "space" "handle" "offset"
-.It Fn bus_space_read_4 "space" "handle" "offset"
-.It Fn bus_space_read_8 "space" "handle" "offset"
-.Pp
+.Ss Fn bus_space_read_1 space handle offset
+.Ss Fn bus_space_read_2 space handle offset
+.Ss Fn bus_space_read_4 space handle offset
+.Ss Fn bus_space_read_8 space handle offset
 The
 .Fn bus_space_read_N
 family of functions reads a 1, 2, 4, or 8 byte data item from
 the offset specified by
 .Fa offset
-into the region specified by 
+into the region specified by
 .Fa handle
-of the bus space specified by 
+of the bus space specified by
 .Fa space .
 The location being read must lie within the bus space region specified by
 .Fa handle .
@@ -738,7 +837,7 @@ plus the offset should be a multiple of the size of data item being read.
 On some systems, not obeying this requirement may cause incorrect data to
 be read, on others it may cause a system crash.
 .Pp
-Read operations done by the 
+Read operations done by the
 .Fn bus_space_read_N
 functions may be executed out
 of order with respect to other pending read and write operations unless
@@ -746,15 +845,15 @@ order is enforced by use of the
 .Fn bus_space_barrier
 function.
 .Pp
-These functions will never fail.  If they would fail (e.g. because of an
+These functions will never fail.
+If they would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case, they will never return.
-.Pp
-.It Fn bus_space_write_1 "space" "handle" "offset" "value"
-.It Fn bus_space_write_2 "space" "handle" "offset" "value"
-.It Fn bus_space_write_4 "space" "handle" "offset" "value"
-.It Fn bus_space_write_8 "space" "handle" "offset" "value"
-.Pp
+panic.
+In that case, they will never return.
+.Ss Fn bus_space_write_1 space handle offset value
+.Ss Fn bus_space_write_2 space handle offset value
+.Ss Fn bus_space_write_4 space handle offset value
+.Ss Fn bus_space_write_8 space handle offset value
 The
 .Fn bus_space_write_N
 family of functions writes a 1, 2, 4, or 8 byte data item to the offset
@@ -762,7 +861,7 @@ specified by
 .Fa offset
 into the region specified by
 .Fa handle
-of the bus space specified by 
+of the bus space specified by
 .Fa space .
 The location being written must lie within
 the bus space region specified by
@@ -771,7 +870,8 @@ the bus space region specified by
 For portability, the starting address of the region specified by
 .Fa handle
 plus the offset should be a multiple of the size of data item being
-written.  On some systems, not obeying this requirement may cause
+written.
+On some systems, not obeying this requirement may cause
 incorrect data to be written, on others it may cause a system crash.
 .Pp
 Write operations done by the
@@ -782,39 +882,36 @@ unless order is enforced by use of the
 .Fn bus_space_barrier
 function.
 .Pp
-These functions will never fail.  If they would fail (e.g. because of an
+These functions will never fail.
+If they would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case, they will never return.
-.El
-.Pp
+panic.
+In that case, they will never return.
 .Sh BARRIERS
-.Pp
 In order to allow high-performance buffering implementations to avoid bus
 activity on every operation, read and write ordering should be specified
-explicitly by drivers when necessary.  The
+explicitly by drivers when necessary.
+The
 .Fn bus_space_barrier
 function provides that ability.
-.Pp
-.Bl -ohang -compact
-.It Fn bus_space_barrier "space" "handle" "offset" "length" "flags"
-.Pp
+.Ss Fn bus_space_barrier space handle offset length flags
 The
 .Fn bus_space_barrier
 function enforces ordering of bus space read and write operations
 for the specified subregion (described by the
 .Fa offset
-and 
+and
 .Fa length
 parameters) of the region named by
 .Fa handle
 in the space named by
 .Fa space .
 .Pp
-The 
+The
 .Fa flags
 argument controls what types of operations are to be ordered.
 Supported flags are:
-.Bl -tag -width BUS_SPACE_BARRIER_WRITE -offset indent
+.Bl -tag -width ".Dv BUS_SPACE_BARRIER_WRITE"
 .It Dv BUS_SPACE_BARRIER_READ
 Synchronize read operations.
 .It Dv BUS_SPACE_BARRIER_WRITE
@@ -830,12 +927,13 @@ specified type(s) of operation done after the barrier.
 .Pp
 Example: Consider a hypothetical device with two single-byte ports, one
 write-only input port (at offset 0) and a read-only output port (at
-offset 1).  Operation of the device is as follows: data bytes are written
+offset 1).
+Operation of the device is as follows: data bytes are written
 to the input port, and are placed by the device on a stack, the top of
-which is read by reading from the output port.  The sequence to correctly
+which is read by reading from the output port.
+The sequence to correctly
 write two data bytes to the device then read those two data bytes back
 would be:
-.Pp
 .Bd -literal
 /*
  * t and h are the tag and handle for the mapped device's
@@ -854,12 +952,14 @@ ndata0 = bus_space_read_1(t, h, 1);
 .Pp
 The first barrier makes sure that the first write finishes before the
 second write is issued, so that two writes to the input port are done
-in order and are not collapsed into a single write.  This ensures that
+in order and are not collapsed into a single write.
+This ensures that
 the data bytes are written to the device correctly and in order.
 .Pp
 The second barrier makes sure that the writes to the output port finish
 before any of the reads to the input port are issued, thereby making sure
-that all of the writes are finished before data is read.  This ensures
+that all of the writes are finished before data is read.
+This ensures
 that the first byte read from the device really is the last one that was
 written.
 .Pp
@@ -867,18 +967,17 @@ The third barrier makes sure that the first read finishes before the
 second read is issued, ensuring that data is read correctly and in order.
 .Pp
 The barriers in the example above are specified to cover the absolute
-minimum number of bus space locations.  It is correct (and often
+minimum number of bus space locations.
+It is correct (and often
 easier) to make barrier operations cover the device's whole range of bus
 space, that is, to specify an offset of zero and the size of the
 whole region.
-.El
-.Pp
 .Sh REGION OPERATIONS
-.Pp
 Some devices use buffers which are mapped as regions in bus space.
 Often, drivers want to copy the contents of those buffers to or from
-memory, e.g. into mbufs which can be passed to higher levels of the
-system or from mbufs to be output to a network.  In order to allow
+memory, e.g.\& into mbufs which can be passed to higher levels of the
+system or from mbufs to be output to a network.
+In order to allow
 drivers to do this as efficiently as possible, the
 .Fn bus_space_read_region_N
 and
@@ -887,18 +986,16 @@ families of functions are provided.
 .Pp
 Drivers occasionally need to copy one region of a bus space to another,
 or to set all locations in a region of bus space to contain a single
-value.  The
+value.
+The
 .Fn bus_space_copy_region_N
 family of functions and the
 .Fn bus_space_set_region_N
 family of functions allow drivers to perform these operations.
-.Pp
-.Bl -ohang -compact
-.It Fn bus_space_read_region_1 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_read_region_2 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_read_region_4 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_read_region_8 "space" "handle" "offset" "datap" "count"
-.Pp
+.Ss Fn bus_space_read_region_1 space handle offset datap count
+.Ss Fn bus_space_read_region_2 space handle offset datap count
+.Ss Fn bus_space_read_region_4 space handle offset datap count
+.Ss Fn bus_space_read_region_8 space handle offset datap count
 The
 .Fn bus_space_read_region_N
 family of functions reads
@@ -914,37 +1011,41 @@ and writes them into the array specified by
 .Fa datap .
 Each successive data item is read from an offset
 1, 2, 4, or 8 bytes after the previous data item (depending on which
-function is used).  All locations being read must lie within the bus
+function is used).
+All locations being read must lie within the bus
 space region specified by
 .Fa handle .
 .Pp
 For portability, the starting address of the region specified by
 .Fa handle
 plus the offset should be a multiple of the size of data items being
-read and the data array pointer should be properly aligned.  On some
+read and the data array pointer should be properly aligned.
+On some
 systems, not obeying these requirements may cause incorrect data to be
 read, on others it may cause a system crash.
 .Pp
 Read operations done by the
 .Fn bus_space_read_region_N
-functions may be executed in any order.  They may also be executed out
+functions may be executed in any order.
+They may also be executed out
 of order with respect to other pending read and write operations unless
 order is enforced by use of the
 .Fn bus_space_barrier
-function.  There is no way to insert barriers between reads of
+function.
+There is no way to insert barriers between reads of
 individual bus space locations executed by the
 .Fn bus_space_read_region_N
 functions.
 .Pp
-These functions will never fail.  If they would fail (e.g. because of an
+These functions will never fail.
+If they would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case, they will never return.
-.Pp
-.It Fn bus_space_write_region_1 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_write_region_2 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_write_region_4 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_write_region_8 "space" "handle" "offset" "datap" "count"
-.Pp
+panic.
+In that case, they will never return.
+.Ss Fn bus_space_write_region_1 space handle offset datap count
+.Ss Fn bus_space_write_region_2 space handle offset datap count
+.Ss Fn bus_space_write_region_4 space handle offset datap count
+.Ss Fn bus_space_write_region_8 space handle offset datap count
 The
 .Fn bus_space_write_region_N
 family of functions reads
@@ -958,45 +1059,49 @@ in the region specified by
 .Fa handle
 of the bus space specified
 by
-.Fa space . 
+.Fa space .
 Each successive data item is written to an offset 1, 2, 4,
 or 8 bytes after the previous data item (depending on which function is
-used).  All locations being written must lie within the bus space region
+used).
+All locations being written must lie within the bus space region
 specified by
 .Fa handle .
 .Pp
 For portability, the starting address of the region specified by
 .Fa handle
 plus the offset should be a multiple of the size of data items being
-written and the data array pointer should be properly aligned.  On some
+written and the data array pointer should be properly aligned.
+On some
 systems, not obeying these requirements may cause incorrect data to be
 written, on others it may cause a system crash.
 .Pp
 Write operations done by the
 .Fn bus_space_write_region_N
 functions may be
-executed in any order.  They may also be executed out of order with
+executed in any order.
+They may also be executed out of order with
 respect to other pending read and write operations unless order is
 enforced by use of the
 .Fn bus_space_barrier
-function.  There is no way to insert barriers between writes of
+function.
+There is no way to insert barriers between writes of
 individual bus space locations executed by the
 .Fn bus_space_write_region_N
 functions.
 .Pp
-These functions will never fail.  If they would fail (e.g. because of an
+These functions will never fail.
+If they would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case, they will never return.
-.Pp
-.It Fn bus_space_copy_region_1 "space" "srchandle" "srcoffset" "dsthandle" \
-"dstoffset" "count"
-.It Fn bus_space_copy_region_2 "space" "srchandle" "srcoffset" "dsthandle" \
-"dstoffset" "count"
-.It Fn bus_space_copy_region_4 "space" "srchandle" "srcoffset" "dsthandle" \
-"dstoffset" "count"
-.It Fn bus_space_copy_region_8 "space" "srchandle" "srcoffset" "dsthandle" \
-"dstoffset" "count"
-.Pp
+panic.
+In that case, they will never return.
+.Ss Fn bus_space_copy_region_1 space srchandle srcoffset dsthandle \
+dstoffset count
+.Ss Fn bus_space_copy_region_2 space srchandle srcoffset dsthandle \
+dstoffset count
+.Ss Fn bus_space_copy_region_4 space srchandle srcoffset dsthandle \
+dstoffset count
+.Ss Fn bus_space_copy_region_8 space srchandle srcoffset dsthandle \
+dstoffset count
 The
 .Fn bus_space_copy_region_N
 family of functions copies
@@ -1012,20 +1117,24 @@ to the area starting at byte offset
 .Fa dstoffset
 in the region specified by
 .Fa dsthandle
-in the same bus space.  Each successive data item read or written has
+in the same bus space.
+Each successive data item read or written has
 an offset 1, 2, 4, or 8 bytes after the previous data item (depending
-on which function is used).  All locations being read and written must
+on which function is used).
+All locations being read and written must
 lie within the bus space region specified by their respective handles.
 .Pp
 For portability, the starting addresses of the regions specified by the
 each handle plus its respective offset should be a multiple of the size
-of data items being copied.  On some systems, not obeying this
+of data items being copied.
+On some systems, not obeying this
 requirement may cause incorrect data to be copied, on others it may cause
 a system crash.
 .Pp
 Read and write operations done by the
 .Fn bus_space_copy_region_N
-functions may be executed in any order.  They may also be executed out
+functions may be executed in any order.
+They may also be executed out
 of order with respect to other pending read and write operations unless
 order is enforced by use of the
 .Fn bus_space_barrier function .
@@ -1039,15 +1148,15 @@ of bus space are handled correctly by the
 .Fn bus_space_copy_region_N
 functions.
 .Pp
-These functions will never fail.  If they would fail (e.g. because of an
+These functions will never fail.
+If they would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case, they will never return.
-.Pp
-.It Fn bus_space_set_region_1 "space" "handle" "offset" "value" "count"
-.It Fn bus_space_set_region_2 "space" "handle" "offset" "value" "count"
-.It Fn bus_space_set_region_4 "space" "handle" "offset" "value" "count"
-.It Fn bus_space_set_region_8 "space" "handle" "offset" "value" "count"
-.Pp
+panic.
+In that case, they will never return.
+.Ss Fn bus_space_set_region_1 space handle offset value count
+.Ss Fn bus_space_set_region_2 space handle offset value count
+.Ss Fn bus_space_set_region_4 space handle offset value count
+.Ss Fn bus_space_set_region_8 space handle offset value count
 The
 .Fn bus_space_set_region_N
 family of functions writes the given
@@ -1059,10 +1168,11 @@ data items in bus space starting at byte offset
 .Fa offset
 in the region specified by
 .Fa handle
-of the bus space specified by 
-.Fa space . 
+of the bus space specified by
+.Fa space .
 Each successive data item has an offset 1, 2, 4, or 8 bytes after the
-previous data item (depending on which function is used).  All
+previous data item (depending on which function is used).
+All
 locations being written must lie within the bus space region specified
 by
 .Fa handle .
@@ -1070,44 +1180,44 @@ by
 For portability, the starting address of the region specified by
 .Fa handle
 plus the offset should be a multiple of the size of data items being
-written.  On some systems, not obeying this requirement may cause
+written.
+On some systems, not obeying this requirement may cause
 incorrect data to be written, on others it may cause a system crash.
 .Pp
 Write operations done by the
 .Fn bus_space_set_region_N
 functions may be
-executed in any order.  They may also be executed out of order with
+executed in any order.
+They may also be executed out of order with
 respect to other pending read and write operations unless order is
 enforced by use of the
 .Fn bus_space_barrier
-function.  There is no way to insert barriers between writes of
+function.
+There is no way to insert barriers between writes of
 individual bus space locations executed by the
 .Fn bus_space_set_region_N
 functions.
 .Pp
-These functions will never fail.  If they would fail (e.g. because of an
+These functions will never fail.
+If they would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case, they will never return.
-.El
-.Pp
+panic.
+In that case, they will never return.
 .Sh READING AND WRITING A SINGLE LOCATION MULTIPLE TIMES
-.Pp
 Some devices implement single locations in bus space which are to be read
-or written multiple times to communicate data, e.g. some ethernet
-devices' packet buffer FIFOs.  In order to allow drivers to manipulate
+or written multiple times to communicate data, e.g.\& some ethernet
+devices' packet buffer FIFOs.
+In order to allow drivers to manipulate
 these types of devices as efficiently as possible, the
 .Fn bus_space_read_multi_N ,
 .Fn bus_space_set_multi_N ,
 and
 .Fn bus_space_write_multi_N
 families of functions are provided.
-.Pp
-.Bl -ohang -compact
-.It Fn bus_space_read_multi_1 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_read_multi_2 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_read_multi_4 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_read_multi_8 "space" "handle" "offset" "datap" "count"
-.Pp
+.Ss Fn bus_space_read_multi_1 space handle offset datap count
+.Ss Fn bus_space_read_multi_2 space handle offset datap count
+.Ss Fn bus_space_read_multi_4 space handle offset datap count
+.Ss Fn bus_space_read_multi_8 space handle offset datap count
 The
 .Fn bus_space_read_multi_N
 family of functions reads
@@ -1122,14 +1232,16 @@ of the bus space specified by
 and writes them into the array specified by
 .Fa datap .
 Each successive data item is read from the same location in bus
-space.  The location being read must lie within the bus space region
+space.
+The location being read must lie within the bus space region
 specified by
 .Fa handle .
 .Pp
 For portability, the starting address of the region specified by
 .Fa handle
 plus the offset should be a multiple of the size of data items being
-read and the data array pointer should be properly aligned.  On some
+read and the data array pointer should be properly aligned.
+On some
 systems, not obeying these requirements may cause incorrect data to be
 read, on others it may cause a system crash.
 .Pp
@@ -1139,21 +1251,22 @@ functions may be
 executed out of order with respect to other pending read and write
 operations unless order is enforced by use of the
 .Fn bus_space_barrier
-function.  Because the
+function.
+Because the
 .Fn bus_space_read_multi_N
 functions read the same bus space location multiple times, they
 place an implicit read barrier between each successive read of that bus
 space location.
 .Pp
-These functions will never fail.  If they would fail (e.g. because of an
+These functions will never fail.
+If they would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case, they will never return.
-.Pp
-.It Fn bus_space_write_multi_1 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_write_multi_2 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_write_multi_4 "space" "handle" "offset" "datap" "count"
-.It Fn bus_space_write_multi_8 "space" "handle" "offset" "datap" "count"
-.Pp
+panic.
+In that case, they will never return.
+.Ss Fn bus_space_write_multi_1 space handle offset datap count
+.Ss Fn bus_space_write_multi_2 space handle offset datap count
+.Ss Fn bus_space_write_multi_4 space handle offset datap count
+.Ss Fn bus_space_write_multi_8 space handle offset datap count
 The
 .Fn bus_space_write_multi_N
 family of functions reads
@@ -1168,14 +1281,16 @@ in the region specified by
 of the bus space specified by
 .Fa space .
 Each successive data item is written to the same location in
-bus space.  The location being written must lie within the bus space
+bus space.
+The location being written must lie within the bus space
 region specified by
 .Fa handle .
 .Pp
 For portability, the starting address of the region specified by
 .Fa handle
 plus the offset should be a multiple of the size of data items being
-written and the data array pointer should be properly aligned.  On some
+written and the data array pointer should be properly aligned.
+On some
 systems, not obeying these requirements may cause incorrect data to be
 written, on others it may cause a system crash.
 .Pp
@@ -1184,34 +1299,33 @@ Write operations done by the
 functions may be executed out of order with respect to other pending
 read and write operations unless order is enforced by use of the
 .Fn bus_space_barrier
-function.  Because the
+function.
+Because the
 .Fn bus_space_write_multi_N
 functions write the same bus space location multiple times, they
 place an implicit write barrier between each successive write of that
 bus space location.
 .Pp
-These functions will never fail.  If they would fail (e.g. because of an
+These functions will never fail.
+If they would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case, they will never return.
-.El
-.Pp
-.Pp
-.It Fn bus_space_set_multi_1 "space" "handle" "offset" "value" "count"
-.It Fn bus_space_set_multi_2 "space" "handle" "offset" "value" "count"
-.It Fn bus_space_set_multi_4 "space" "handle" "offset" "value" "count"
-.It Fn bus_space_set_multi_8 "space" "handle" "offset" "value" "count"
-.Pp
+panic.
+In that case, they will never return.
+.Ss Fn bus_space_set_multi_1 space handle offset value count
+.Ss Fn bus_space_set_multi_2 space handle offset value count
+.Ss Fn bus_space_set_multi_4 space handle offset value count
+.Ss Fn bus_space_set_multi_8 space handle offset value count
 The
 .Fn bus_space_set_multi_N
 writes
-.Fa value 
+.Fa value
 into bus space at byte offset
 .Fa offset
 in the region specified by
 .Fa handle
 of the bus space specified by
-.Fa space 
-.Fa count 
+.Fa space ,
+.Fa count
 times.
 The location being written must lie within the bus space
 region specified by
@@ -1220,7 +1334,8 @@ region specified by
 For portability, the starting address of the region specified by
 .Fa handle
 plus the offset should be a multiple of the size of data items being
-written and the data array pointer should be properly aligned.  On some
+written and the data array pointer should be properly aligned.
+On some
 systems, not obeying these requirements may cause incorrect data to be
 written, on others it may cause a system crash.
 .Pp
@@ -1229,32 +1344,32 @@ Write operations done by the
 functions may be executed out of order with respect to other pending
 read and write operations unless order is enforced by use of the
 .Fn bus_space_barrier
-function.  Because the
+function.
+Because the
 .Fn bus_space_set_multi_N
 functions write the same bus space location multiple times, they
 place an implicit write barrier between each successive write of that
 bus space location.
 .Pp
-These functions will never fail.  If they would fail (e.g. because of an
+These functions will never fail.
+If they would fail (e.g.\& because of an
 argument error), that indicates a software bug which should cause a
-panic.  In that case, they will never return.
-.El
-.Pp
+panic.
+In that case, they will never return.
 .Sh COMPATIBILITY
-.Pp
-The current 
-.Nx 
+The current
+.Nx
 version of the
 .Nm
 interface specification differs slightly from the original
-specification that came into wide use and 
-.Fx 
+specification that came into wide use and
+.Fx
 adopted.
 A few of the function names and arguments have changed
 for consistency and increased functionality.
-.Pp
+.Sh SEE ALSO
+.Xr bus_dma 9
 .Sh HISTORY
-.Pp
 The
 .Nm
 functions were introduced in a different form (memory and I/O spaces
@@ -1267,39 +1382,45 @@ early in the
 development cycle, and many drivers were converted to use them.
 This document was written later during the
 .Nx 1.3
-development cycle and the specification was updated to fix some
+development cycle, and the specification was updated to fix some
 consistency problems and to add some missing functionality.
 .Pp
 The manual page was then adopted to the version of the interface that
-.Fx 
+.Fx
 imported for the CAM SCSI drivers, plus subsequent evolution.
-The 
-.Fx 
+The
+.Fx
 .Nm
 version was imported in
 .Fx 3.0 .
 .Sh AUTHORS
-.Pp
+.An -nosplit
 The
 .Nm
 interfaces were designed and implemented by the
 .Nx
 developer
-community.  Primary contributors and implementors were Chris Demetriou,
-Jason Thorpe, and Charles Hannum, but the rest of the
+community.
+Primary contributors and implementors were
+.An Chris Demetriou ,
+.An Jason Thorpe ,
+and
+.An Charles Hannum ,
+but the rest of the
 .Nx
 developers and the user community played a significant role in development.
 .Pp
-Justin Gibbs ported these interfaces to
+.An Justin Gibbs
+ported these interfaces to
 .Fx .
 .Pp
-Chris Demetriou wrote this manual page.
+.An Chris Demetriou
+wrote this manual page.
 .Pp
-Warner Losh modified it for the
-.Fx  
+.An Warner Losh
+modified it for the
+.Fx
 implementation.
-.Sh SEE ALSO
-.Xr bus_dma 9
 .Sh BUGS
-This manual man not completely and accurately document the interface
+This manual may not completely and accurately document the interface,
 and many parts of the interface are unspecified.