January 10, 2008 elanpar 4 i386

### NAME

elanpar - AMD Elan SC520 Programmable Address Regions

### SYNOPSIS

elansc* at mainbus? bus ? elanpar* at elansc?

### DESCRIPTION

The elanpar driver supports the write-protect feature of the AMD Elan SC520 microcontroller's integrated Programmable Address Regions. Currently, elanpar protects the kernel text from being overwritten by the CPU or errant DMA.

### DIAGNOSTICS

elanpar0: cpu violated write-protect window %u

elanpar0: gp violated write-protect window %u

elanpar0: pci violated write-protect window %u

A Programmable Address Region stopped either the CPU, the general-purpose bus (gp), or a PCI bus master from writing to the indicated window of write-protected memory.

elanpar0: %u bytes of kernel text are unprotected

elanpar has not write-protected %u bytes of the kernel text.

### SEE ALSO

dmesg(8), elanpex(4), elansc(4), syslogd(8).

### BUGS

elanpar leaves as many as 65535 bytes unprotected at the beginning and end of kernel text. Also, elanpar is not compatible with setting breakpoints using ddb(4). Disable elanpar using drvctl -d elanpar0 before setting a breakpoint with ddb(4).

### HISTORY

The elanpar device first appeared in NetBSD5.0.

### AUTHORS

The elanpar driver was written by David Young <dyoung@NetBSD.org>
.