/* $NetBSD: nvm.h,v 1.1 2014/02/24 07:23:43 skrll Exp $ */
/* $OpenBSD: nvm.h,v 1.2 1998/11/23 03:28:22 mickey Exp $ */
/*
* Copyright (c) 1990, 1994 The University of Utah and
* the Computer Systems Laboratory at the University of Utah (CSL).
* All rights reserved.
*
* Permission to use, copy, modify and distribute this software is hereby
* granted provided that (1) source code retains these copyright, permission,
* and disclaimer notices, and (2) redistributions including binaries
* reproduce the notices in supporting documentation, and (3) all advertising
* materials mentioning features or use of this software display the following
* acknowledgement: ``This product includes software developed by the
* Computer Systems Laboratory at the University of Utah.''
*
* THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS
* IS" CONDITION. THE UNIVERSITY OF UTAH AND CSL DISCLAIM ANY LIABILITY OF
* ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* CSL requests users of this software to return to
[email protected] any
* improvements that they make and grant CSL redistribution rights.
*
* Utah $Hdr: nvm.h 1.4 94/12/14$
* Author: Jeff Forys, University of Utah CSL
*/
#ifndef _MACHINE_NVM_H_
#define _MACHINE_NVM_H_
/*
* The PDC provides access to Non-Volatile Memory (NVM). If this
* is implemented (it's HVERSION dependent), the first 256 bytes
* are formatted as follows:
*
* 0x000 +----------------------------+
* | Implementation information |
* 0x024 +----------------------------+
* | |
* | IPL information |
* | |
* 0x080 +----------------------------+
* | |
* | |
* | OS Panic information |
* | |
* | |
* 0x100 +----------------------------+
*
* It appears that there are at least 256 bytes of NVM, and only
* the "OS Panic information" is not architected. This means that
* we can use locations 0x80 - 0xFF for saving information across
* boots (e.g. boot flags and boot device). I think we should use
* the higher portions of this space first, to avoid conflicting
* with possible future HP-PA plans for the NVM.
*
* The PDC requires that NVM be read/written to in word multiples.
*/
/*
* Boot flags and boot device (0xF4 - 0xFF).
*/
#define NVM_BOOTDATA 0xF4 /* location of bootdata in NVM */
#define NVM_BOOTMAGIC 0xACCEDE /* magic used for bootdata cksum */
#define NVM_BOOTCKSUM(bd) \
((unsigned int) NVM_BOOTMAGIC + (bd).flags + (bd).device)
struct bootdata {
unsigned int cksum; /* NVM_BOOTMAGIC + flags + device */
unsigned int flags; /* boot flags */
unsigned int device; /* boot device */
};
#endif /* _MACHINE_NVM_H_ */
