ref: c8168fd3bcd752264dd1a52c44c816bc9b22bf9d
parent: 78e19b52bf09a480341b89914b9835b3c3d5e78c
author: cinap_lenrek <cinap_lenrek@centraldogma>
date: Sat Aug 27 03:42:13 EDT 2011
arch(3): document msr
--- a/sys/man/3/arch
+++ b/sys/man/3/arch
@@ -12,6 +12,7 @@
.B /dev/iol
.B /dev/iow
.B /dev/irqalloc
+.B /dev/msr
.SH DESCRIPTION
This device presents textual information about PC hardware and allows
user-level control of the I/O ports on x86-class and DEC Alpha machines.
@@ -116,11 +117,15 @@
.IR iob ,
.IR iow ,
and
-.I iol
+.IR iol
cause 8-bit wide, 16-bit wide, and 32-bit wide requests to
I/O ports.
The port accessed is determined by the byte offset of the
file descriptor.
+.PP
+Reads and writes to
+.I msr
+go to the P4/P6/Core/Core2/AMD64 MSRs.
.SH EXAMPLE
The following code reads from an x86 byte I/O port.
.IP