1.\" Copyright (c) 1999 Chris Costello 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd September 15, 2002 28.Dt MEMCONTROL 8 29.Os 30.Sh NAME 31.Nm memcontrol 32.Nd "control system cache behaviour with respect to memory" 33.Sh SYNOPSIS 34.Nm 35.Cm list 36.Op Fl a 37.Nm 38.Cm set 39.Fl b Ar base 40.Fl l Ar length 41.Fl o Ar owner 42.Ar attribute 43.Nm 44.Cm clear 45.Fl o Ar owner 46.Nm 47.Cm clear 48.Fl b Ar base 49.Fl l Ar length 50.Sh DESCRIPTION 51A number of supported system architectures allow the behaviour of the CPU 52cache to be programmed to behave differently depending on the region being 53written. 54.Pp 55The 56.Nm 57utility 58provides an interface to this facility, allowing CPU cache behavior to 59be altered for ranges of system physical memory. 60.Pp 61These ranges are typically power-of-2 aligned and sized, however the specific 62rules governing their layout vary between architectures. 63The 64.Nm 65utility does not attempt to enforce these rules, however the system will 66reject any attempt to set an illegal combination. 67.Bl -tag -width ".Cm clear" 68.It Cm list 69List range slots. 70.Bl -tag -width indent 71.It Fl a 72List all range slots, even those that are inactive. 73.El 74.It Cm set 75Set memory range attributes. 76.Bl -tag -width indent 77.It Fl b Ar base 78Memory range base address. 79.It Fl l Ar length 80Length of memory range in bytes, power of 2. 81.It Fl o Ar owner 82Text identifier for this setting (7 char max). 83.It Ar attribute 84Attributes applied to this range; combinations of 85.Cm force , uncacheable , write-combine , write-through , write-back , 86and 87.Cm write-protect . 88.El 89.It Cm clear 90Clear memory range attributes. 91Ranges may be cleared by owner or by 92base/length combination. 93.Pp 94To clear based on ownership: 95.Bl -tag -width indent 96.It Fl o Ar owner 97All ranges with this owner will be cleared. 98.El 99.Pp 100To clear based on the base/length combination: 101.Bl -tag -width indent 102.It Fl b Ar base 103Memory range base address. 104.It Fl l Ar length 105Length of memory range in bytes, power of 2. 106.El 107.Pp 108Base and length must exactly match an existing range. 109.El 110.Sh SEE ALSO 111.Xr mem 4 112