1.\" $NetBSD: elanpar.4,v 1.9 2017/02/17 22:24:46 christos Exp $ 2.\" 3.\" 4.\" Copyright (c) 2008 David Young. All rights reserved. 5.\" 6.\" Written by David Young. 7.\" 8.\" Redistribution and use in source and binary forms, with or 9.\" without modification, are permitted provided that the following 10.\" conditions are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above 14.\" copyright notice, this list of conditions and the following 15.\" disclaimer in the documentation and/or other materials 16.\" provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY 19.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 20.\" THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 21.\" PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID 22.\" YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 23.\" EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 24.\" TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 26.\" ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 27.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29.\" POSSIBILITY OF SUCH DAMAGE. 30.\" 31.Dd February 17, 2017 32.Dt ELANPAR 4 i386 33.Os 34.Sh NAME 35.Nm elanpar 36.Nd AMD Elan SC520 Programmable Address Regions 37.Sh SYNOPSIS 38.Cd "elansc* at mainbus? bus ?" 39.Cd "elanpar* at elansc?" 40.Sh DESCRIPTION 41The 42.Nm 43driver supports the write-protect feature of the AMD 44Elan SC520 microcontroller's integrated Programmable Address Regions. 45Currently, 46.Nm 47protects the kernel text from being overwritten by the CPU or errant DMA. 48.Sh DIAGNOSTICS 49.Bl -diag 50.It elanpar0: cpu violated write-protect window %u 51.It elanpar0: gp violated write-protect window %u 52.It elanpar0: pci violated write-protect window %u 53.El 54.Pp 55A Programmable Address Region stopped 56either the CPU, the general-purpose bus 57.Pq gp , 58or a PCI bus master from writing to the indicated window of 59write-protected memory. 60.Bl -diag 61.It elanpar0: %u bytes of kernel text are unprotected 62.El 63.Pp 64.Nm 65has not write-protected 66.Em %u 67bytes of the kernel text. 68.Sh SEE ALSO 69.Xr i386/elanpex 4 , 70.Xr i386/elansc 4 , 71.Xr dmesg 8 , 72.Xr syslogd 8 73.Sh HISTORY 74The 75.Nm 76device first appeared in 77.Nx 5.0 . 78.Sh AUTHORS 79The 80.Nm 81driver was written by 82.An David Young Aq Mt dyoung@NetBSD.org . 83.Sh BUGS 84.Nm 85leaves as many as 65535 bytes unprotected at the beginning and 86end of kernel text. 87Also, 88.Nm 89is not compatible with setting breakpoints 90using 91.Xr ddb 4 . 92Disable 93.Nm 94using 95.Ic drvctl Fl d Ar elanpar0 96before setting a breakpoint with 97.Xr ddb 4 . 98