| ELANPAR(4) | Device Drivers Manual (i386) | ELANPAR(4) | 
elanpar —
elansc* at mainbus? bus ?
elanpar* at elansc?
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.
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.
elanpar has not write-protected
    %u bytes of the kernel text.
elanpar device first appeared in
  NetBSD 5.0.
elanpar driver was written by David
  Young
  <dyoung@NetBSD.org>.
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).
| February 17, 2017 | NetBSD 9.4 |