Add a port of FreeBSD/alpha's libio as libalpha. This library enable

access to devices I/O ports from userland. Only BWX machines supported
for now. Added a man page.
Ok deraadt@, miod@.

6 files changed, 667 insertions, 1 deletions

diff --git a/etc/mtree/4.4BSD.dist b/etc/mtree/4.4BSD.dist
index 41586ac51ca..c9502d1cc87 100644
--- a/etc/mtree/4.4BSD.dist
+++ b/etc/mtree/4.4BSD.dist
@@ -1,4 +1,4 @@
-#	$OpenBSD: 4.4BSD.dist,v 1.130 2002/06/11 17:15:13 beck Exp $
+#	$OpenBSD: 4.4BSD.dist,v 1.131 2002/07/07 14:24:04 matthieu Exp $
 
 /set type=dir uname=root gname=wheel mode=0755
 # .
@@ -1094,6 +1094,10 @@ vax
 # ./usr/share/man/cat2
 cat2
 
+# ./usr/share/man/cat2/alpha
+alpha
+..
+
 # ./usr/share/man/cat2/i386
 i386
 
diff --git a/lib/libarch/alpha/Makefile b/lib/libarch/alpha/Makefile
new file mode 100644
index 00000000000..1e6585314f6
--- /dev/null
+++ b/lib/libarch/alpha/Makefile
@@ -0,0 +1,30 @@
+# $FreeBSD: src/lib/libio/Makefile,v 1.2 1999/08/28 00:04:42 peter Exp $
+# $OpenBSD: Makefile,v 1.5 2002/07/07 14:24:04 matthieu Exp $
+
+NOPIC=
+SRCS=		io.c bwx.c
+
+CFLAGS+= 	-Wall -Wno-uninitialized -Wa,-mev56
+
+MAN=		libalpha.2
+
+MLINKS+=	libalpha.2 dense_base.2 \
+		libalpha.2 inb.2 \
+		libalpha.2 inl.2 \
+		libalpha.2 inw.2 \
+		libalpha.2 ioperm.2 \
+		libalpha.2 map_memory.2 \
+		libalpha.2 outb.2 \
+		libalpha.2 outl.2 \
+		libalpha.2 outw.2 \
+		libalpha.2 readb.2 \
+		libalpha.2 readl.2 \
+		libalpha.2 readw.2 \
+		libalpha.2 unmap_memory.2 \
+		libalpha.2 writeb.2 \
+		libalpha.2 writel.2 \
+		libalpha.2 writew.2
+
+MANSUBDIR=alpha
+
+.include <bsd.lib.mk>
diff --git a/lib/libarch/alpha/bwx.c b/lib/libarch/alpha/bwx.c
new file mode 100644
index 00000000000..1eaa67f8359
--- /dev/null
+++ b/lib/libarch/alpha/bwx.c
@@ -0,0 +1,263 @@
+/* $OpenBSD: bwx.c,v 1.1 2002/07/07 14:24:04 matthieu Exp $ */
+/*-
+ * Copyright (c) 1998 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+
+#define vm_page_size (sysconf(_SC_PAGESIZE)) /* XXX  */
+#include <sys/param.h>
+#include <sys/mman.h>
+#include <sys/fcntl.h>
+#include <sys/sysctl.h>
+#include <err.h>
+#include <paths.h>
+#include <machine/bwx.h>
+#include <machine/sysarch.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "io.h"
+
+#define mb()	__asm__ __volatile__("mb"  : : : "memory")
+#define wmb()	__asm__ __volatile__("wmb" : : : "memory")
+
+static int		mem_fd;		/* file descriptor to /dev/mem */
+static void	       *bwx_int1_ports;	/* mapped int1 io ports */
+static void	       *bwx_int2_ports;	/* mapped int2 io ports */
+static void	       *bwx_int4_ports;	/* mapped int4 io ports */
+static u_int64_t	bwx_io_base;	/* physical address of ports */
+static u_int64_t	bwx_mem_base;	/* physical address of bwx mem */
+
+static void
+bwx_init(void)
+{
+	size_t len = sizeof(u_int64_t);
+	int error;
+	int mib[3];
+	
+	mem_fd = open(_PATH_MEM, O_RDWR);
+	if (mem_fd < 0)
+		err(1, _PATH_MEM);
+	
+	mib[0] = CTL_MACHDEP;
+	mib[1] = CPU_CHIPSET;
+	mib[2] = CPU_CHIPSET_PORTS;
+	if ((error = sysctl(mib, 3, &bwx_io_base, &len, NULL, 0)) < 0)
+		err(1, "machdep.chipset.ports_base");
+	mib[2] = CPU_CHIPSET_MEM;
+	if ((error = sysctl(mib, 3, &bwx_mem_base, &len, 0, 0)) < 0)
+		err(1, "machdep.chipset.memory");
+}
+
+static int
+bwx_ioperm(u_int32_t from, u_int32_t num, int on)
+{
+	u_int32_t start, end;
+
+	if (!bwx_int1_ports)
+		bwx_init();
+
+	if (!on)
+		return -1;		/* XXX can't unmap yet */
+	
+	start = trunc_page(from);
+	end = round_page(from + num);
+	if ((bwx_int1_ports = mmap(0, end-start, 
+				   PROT_READ|PROT_WRITE, MAP_SHARED, mem_fd, 
+				   bwx_io_base + BWX_EV56_INT1 + start))
+	     == MAP_FAILED) 
+		err(1, "mmap int1");
+	if ((bwx_int2_ports = mmap(0, end-start, 
+				   PROT_READ|PROT_WRITE, MAP_SHARED, mem_fd, 
+				   bwx_io_base + BWX_EV56_INT2 + start))
+	    == MAP_FAILED)
+		err(1, "mmap int2");
+	if ((bwx_int4_ports = mmap(0, end-start, 
+				   PROT_READ|PROT_WRITE, MAP_SHARED, mem_fd, 
+				   bwx_io_base + BWX_EV56_INT4 + start))
+	    == MAP_FAILED) 
+		err(1, "mmap int4");
+	return 0;
+}
+
+static u_int8_t
+bwx_inb(u_int32_t port)
+{
+	mb();
+	return alpha_ldbu(bwx_int1_ports + port);
+}
+
+static u_int16_t
+bwx_inw(u_int32_t port)
+{
+	mb();
+	return alpha_ldwu(bwx_int2_ports + port);
+}
+
+static u_int32_t
+bwx_inl(u_int32_t port)
+{
+	mb();
+	return alpha_ldlu(bwx_int4_ports + port);
+}
+
+static void
+bwx_outb(u_int32_t port, u_int8_t val)
+{
+	alpha_stb(bwx_int1_ports + port, val);
+	mb();
+	wmb();
+}
+
+static void
+bwx_outw(u_int32_t port, u_int16_t val)
+{
+	alpha_stw(bwx_int2_ports + port, val);
+	mb();
+	wmb();
+}
+
+static void
+bwx_outl(u_int32_t port, u_int32_t val)
+{
+	alpha_stl(bwx_int4_ports + port, val);
+	mb();
+	wmb();
+}
+
+struct bwx_mem_handle {
+	void	*virt1;		/* int1 address in user address-space */
+	void	*virt2;		/* int2 address in user address-space */
+	void	*virt4;		/* int4 address in user address-space */
+};
+
+static void *
+bwx_map_memory(u_int32_t address, u_int32_t size)
+{
+	struct bwx_mem_handle *h;
+
+	h = malloc(sizeof(struct bwx_mem_handle));
+	if (!h) return 0;
+	h->virt1 = mmap(0, size << 5, PROT_READ|PROT_WRITE, MAP_SHARED,
+			mem_fd, bwx_mem_base + BWX_EV56_INT1 + address);
+	if ((long) h->virt1 == -1) {
+		free(h);
+		return 0;
+	}
+	h->virt2 = mmap(0, size << 5, PROT_READ|PROT_WRITE, MAP_SHARED,
+			mem_fd, bwx_mem_base + BWX_EV56_INT2 + address);
+	if ((long) h->virt2 == -1) {
+		munmap(h->virt1, size);
+		free(h);
+		return 0;
+	}
+	h->virt4 = mmap(0, size << 5, PROT_READ|PROT_WRITE, MAP_SHARED,
+			mem_fd, bwx_mem_base + BWX_EV56_INT4 + address);
+	if ((long) h->virt4 == -1) {
+		munmap(h->virt1, size);
+		munmap(h->virt2, size);
+		free(h);
+		return 0;
+	}
+	return h;
+}
+
+static void
+bwx_unmap_memory(void *handle, u_int32_t size)
+{
+	struct bwx_mem_handle *h = handle;
+
+	munmap(h->virt1, size);
+	munmap(h->virt2, size);
+	munmap(h->virt4, size);
+	free(h);
+}
+
+static u_int8_t
+bwx_readb(void *handle, u_int32_t offset)
+{
+	struct bwx_mem_handle *h = handle;
+
+	return alpha_ldbu(h->virt1 + offset);
+}
+
+static u_int16_t
+bwx_readw(void *handle, u_int32_t offset)
+{
+	struct bwx_mem_handle *h = handle;
+
+	return alpha_ldwu(h->virt2 + offset);
+}
+
+static u_int32_t
+bwx_readl(void *handle, u_int32_t offset)
+{
+	struct bwx_mem_handle *h = handle;
+
+	return alpha_ldlu(h->virt4 + offset);
+}
+
+static void
+bwx_writeb(void *handle, u_int32_t offset, u_int8_t val)
+{
+	struct bwx_mem_handle *h = handle;
+
+	alpha_stb(h->virt1 + offset, val);
+}
+
+static void
+bwx_writew(void *handle, u_int32_t offset, u_int16_t val)
+{
+	struct bwx_mem_handle *h = handle;
+
+	alpha_stw(h->virt2 + offset, val);
+}
+
+static void
+bwx_writel(void *handle, u_int32_t offset, u_int32_t val)
+{
+	struct bwx_mem_handle *h = handle;
+
+	alpha_stl(h->virt4 + offset, val);
+}
+
+struct io_ops bwx_io_ops = {
+	bwx_ioperm,
+	bwx_inb,
+	bwx_inw,
+	bwx_inl,
+	bwx_outb,
+	bwx_outw,
+	bwx_outl,
+	bwx_map_memory,
+	bwx_unmap_memory,
+	bwx_readb,
+	bwx_readw,
+	bwx_readl,
+	bwx_writeb,
+	bwx_writew,
+	bwx_writel,
+};
diff --git a/lib/libarch/alpha/io.c b/lib/libarch/alpha/io.c
new file mode 100644
index 00000000000..89c648a2064
--- /dev/null
+++ b/lib/libarch/alpha/io.c
@@ -0,0 +1,187 @@
+/* $OpenBSD: io.c,v 1.1 2002/07/07 14:24:04 matthieu Exp $ */
+/*-
+ * Copyright (c) 1998 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#include <err.h>
+
+#include "io.h"
+
+static struct io_ops *ops;
+
+int
+ioperm(unsigned long from, unsigned long num, int on)
+{
+	int error;
+	int bwx;
+	size_t len = sizeof(bwx);
+	int mib[3];
+
+	mib[0] = CTL_MACHDEP;
+	mib[1] = CPU_CHIPSET;
+	mib[2] = CPU_CHIPSET_BWX;
+	if ((error = sysctl(mib, 3, &bwx, &len, NULL, 0)) < 0)
+		return error;
+	if (bwx)
+		ops = &bwx_io_ops;
+	else
+#ifdef notyet
+		ops = &swiz_io_ops;
+#else
+	errx(1, "libio is only available on bwx capable machines");
+#endif
+	
+	return ops->ioperm(from, num, on);
+}
+
+u_int8_t
+inb(u_int32_t port)
+{
+	return ops->inb(port);
+}
+
+u_int16_t
+inw(u_int32_t port)
+{
+	return ops->inw(port);
+}
+
+u_int32_t
+inl(u_int32_t port)
+{
+	return ops->inl(port);
+}
+
+void
+outb(u_int32_t port, u_int8_t val)
+{
+	ops->outb(port, val);
+}
+
+void
+outw(u_int32_t port, u_int16_t val)
+{
+	ops->outw(port, val);
+}
+
+void
+outl(u_int32_t port, u_int32_t val)
+{
+	ops->outl(port, val);
+}
+
+void *
+map_memory(u_int32_t address, u_int32_t size)
+{
+	return ops->map_memory(address, size);
+}
+
+void
+unmap_memory(void *handle, u_int32_t size)
+{
+	ops->unmap_memory(handle, size);
+}
+
+u_int8_t
+readb(void *handle, u_int32_t offset)
+{
+	return ops->readb(handle, offset);
+}
+
+u_int16_t
+readw(void *handle, u_int32_t offset)
+{
+	return ops->readw(handle, offset);
+}
+
+u_int32_t
+readl(void *handle, u_int32_t offset)
+{
+	return ops->readl(handle, offset);
+}
+
+void
+writeb(void *handle, u_int32_t offset, u_int8_t val)
+{
+	ops->writeb(handle, offset, val);
+	__asm__ __volatile__ ("mb");
+}
+
+void
+writew(void *handle, u_int32_t offset, u_int16_t val)
+{
+	ops->writew(handle, offset, val);
+	__asm__ __volatile__ ("mb");
+}
+
+void
+writel(void *handle, u_int32_t offset, u_int32_t val)
+{
+	ops->writel(handle, offset, val);
+	__asm__ __volatile__ ("mb");
+}
+
+void
+writeb_nb(void *handle, u_int32_t offset, u_int8_t val)
+{
+	return ops->writeb(handle, offset, val);
+}
+
+void
+writew_nb(void *handle, u_int32_t offset, u_int16_t val)
+{
+	return ops->writew(handle, offset, val);
+}
+
+void
+writel_nb(void *handle, u_int32_t offset, u_int32_t val)
+{
+	return ops->writel(handle, offset, val);
+}
+
+u_int64_t
+dense_base(void)
+{
+	static u_int64_t base = 0;
+	
+	if (base == 0) {
+		size_t len = sizeof(base);
+		int error;
+		int mib[3];
+		
+		mib[0] = CTL_MACHDEP;
+		mib[1] = CPU_CHIPSET;
+		mib[2] = CPU_CHIPSET_DENSE;
+		
+		if ((error = sysctl(mib, 3, &base, &len, NULL, 0)) < 0)
+			err(1, "machdep.chipset.dense_base");
+	}
+	
+	return base;
+}
diff --git a/lib/libarch/alpha/io.h b/lib/libarch/alpha/io.h
new file mode 100644
index 00000000000..6d7a45f5f50
--- /dev/null
+++ b/lib/libarch/alpha/io.h
@@ -0,0 +1,49 @@
+/* $OpenBSD: io.h,v 1.1 2002/07/07 14:24:04 matthieu Exp $ */
+/*-
+ * Copyright (c) 1998 Doug Rabson
+ * 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: src/lib/libio/io.h,v 1.2 1999/08/28 00:04:44 peter Exp $
+ */
+
+struct io_ops {
+	int	  (*ioperm)(u_int32_t, u_int32_t, int);
+	u_int8_t  (*inb)(u_int32_t);
+	u_int16_t (*inw)(u_int32_t);
+	u_int32_t (*inl)(u_int32_t);
+	void	  (*outb)(u_int32_t, u_int8_t);
+	void	  (*outw)(u_int32_t, u_int16_t);
+	void	  (*outl)(u_int32_t, u_int32_t);
+	void 	 *(*map_memory)(u_int32_t, u_int32_t);
+	void	  (*unmap_memory)(void *, u_int32_t);
+	u_int8_t  (*readb)(void *, u_int32_t);
+	u_int16_t (*readw)(void *, u_int32_t);
+	u_int32_t (*readl)(void *, u_int32_t);
+	void	  (*writeb)(void *, u_int32_t, u_int8_t);
+	void	  (*writew)(void *, u_int32_t, u_int16_t);
+	void	  (*writel)(void *, u_int32_t, u_int32_t);
+};
+
+extern struct io_ops swiz_io_ops;
+extern struct io_ops bwx_io_ops;
diff --git a/lib/libarch/alpha/libalpha.2 b/lib/libarch/alpha/libalpha.2
new file mode 100644
index 00000000000..f8006e19293
--- /dev/null
+++ b/lib/libarch/alpha/libalpha.2
@@ -0,0 +1,133 @@
+.\" $OpenBSD: libalpha.2,v 1.1 2002/07/07 14:24:04 matthieu Exp $
+.\"
+.\" Copyright (c) 2002 Matthieu Herrb
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\"
+.\"    - Redistributions of source code must retain the above copyright
+.\"      notice, this list of conditions and the following disclaimer.
+.\"    - 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 COPYRIGHT HOLDERS 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
+.\" COPYRIGHT HOLDERS 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.
+.\"
+.Dd Jul 6, 2002
+.Dt LIBALPHA 2
+.Os
+.Sh NAME
+.Nm dense_base ,
+.Nm inb ,
+.Nm inl ,
+.Nm inw ,
+.Nm ioperm ,
+.Nm map_memory ,
+.Nm outb ,
+.Nm outl ,
+.Nm outw ,
+.Nm readb ,
+.Nm readl ,
+.Nm readw , 
+.Nm unmap_memory ,
+.Nm writeb , 
+.Nm writel ,
+.Nm writew
+.Nd Alpha devices I/O ports and memory access functions
+.Sh SYNOPSIS
+.Ft u_int64_t
+.Fn dense_base "void"
+.Ft u_int8_t
+.Fn inb "u_int32_t port"
+.Ft u_int32_t
+.Fn inl "u_int32_t port"
+.Ft u_int16_t
+.Fn inw "u_int32_t port"
+.Ft int
+.Fn ioperm "unsigned long from" "unsigned long num" "int on"
+.Ft void *
+.Fn map_memory "u_int32_t address" "u_int32_t size"
+.Ft void
+.Fn outb "u_int32_t port" "u_int8_t val"
+.Ft void
+.Fn outl "u_int32_t port" "u_int32_t val"
+.Ft void
+.Fn outw "u_int32_t port" "u_int16_t val"
+.Ft u_int8_t
+.Fn readb "void *handle" "u_int32_t offset"
+.Ft u_int32_t
+.Fn readl "void *handle" "u_int32_t offset"
+.Ft u_int16_t
+.Fn readw "void *handle" "u_int32_t offset"
+.Ft void
+.Fn unmap_memory "void *handle" "u_int32_t size"
+.Ft void
+.Fn writeb "void *handle" "u_int32_t offset" "u_int8_t val"
+.Ft void
+.Fn writel "void *handle" "u_int32_t offset" "u_int32_t val"
+.Ft void
+.Fn writew "void *handle" "u_int32_t offset" "u_int16_t val"
+.Sh DESCRIPTION
+The functions in libalpha give userland programs access to the I/O
+ports on the OpenBSD/alpha platform. 
+.Pp
+The 
+.Fn in*
+functions return data read from the specified I/O port. 
+.Pp
+The 
+.Fn out*
+functions write data to the specified I/O port. 
+.Pp
+.Fn ioperm
+enables the access to to the specified  port numbers if 
+.Fa on
+is 
+.Dv TRUE
+and disables access if 
+.Fa on
+is 
+.Dv FALSE . 
+.Pp 
+The 
+.Fn map_memory 
+function allows a user program to map part of a device memory.
+.Pp
+The 
+.Fn unmap_memory
+function unmaps memory that was previously mapped by
+.Fn map_memory . 
+.Pp
+The
+.Fn read*
+functions read data from device memory previously mapped by
+.Fn map_memory . 
+.Pp
+The 
+.Fn write*
+functions write datz to the device memory previously mapped by
+.Fn map_memory .
+.\" .Sh EXAMPLES
+.\" TBW
+.Sh HISTORY
+These functions originally appeared in
+.Fx .
+.Sh CAVEATS
+Only BWX bus access method is supported for now. Machines requiring
+swiz type access are not supported. 
+.Pp
+Root credentials are needed to use these functions.