Date: Thu, 15 Jan 2004 19:39:36 -0800 (PST) From: Ted Unangst <tedu@stanford.edu> To: Steve Watt <steve@Watt.COM> Cc: hackers@freebsd.org Subject: Re: kernel environment between reboots, diskless Message-ID: <Pine.GSO.4.44.0401151931490.7625-100000@elaine30.Stanford.EDU> In-Reply-To: <200401142055.i0EKtnL6085950@wattres.Watt.COM>
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On Wed, 14 Jan 2004, Steve Watt wrote: > I'm trying to see if there's a way to get that information into the > loader (or the driver) in some way that doesn't require rewriting a file > in the flash every reboot, to avoid flash write cycles. > > I know there's some amount of NVRAM in PCs, but didn't spot anything > about how to get at it from the driver. It'd be nice, for this > sort of application, if there was a way to stash somewhere between > 2 and 8 bytes somewhere... many (most?) PCs don't clear RAM on soft reboot, so stuff like the message buffer survives. try mapping the same physical address, out of the way of other code, and leaving your data there. --
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