Date: Thu, 02 Dec 1999 14:06:58 -0800 From: Mike Smith <msmith@freebsd.org> To: Warner Losh <imp@village.org> Cc: "Matthew N. Dodd" <winter@jurai.net>, Nick Hibma <hibma@skylink.it>, Christopher Masto <chris@netmonger.net>, Mike Smith <msmith@FreeBSD.ORG>, FreeBSD CURRENT Mailing List <current@FreeBSD.ORG> Subject: Re: PCCARD eject freeze (was Re: your mail) Message-ID: <199912022206.OAA00629@mass.cdrom.com> In-Reply-To: Your message of "Thu, 02 Dec 1999 12:11:51 MST." <199912021911.MAA03854@harmony.village.org>
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> In message <Pine.BSF.4.20.9912021236410.10542-100000@sasami.jurai.net> "Matthew N. Dodd" writes: > : On Thu, 2 Dec 1999, Nick Hibma wrote: > : > PCMCIA has the problem that the hardware register you are talking to can > : > disappear on the spot, between 2 outb()s. > : > : Can't we do something about this using bus_space? This would give us a > : fair bit of overhead for PCMCIA devices as well as require us to more > : tightly couple newbus and bus_space (we'd probably want to 'cache' a > : function pointer to the method to avoid method lookup overhead.) > > I had the same thought, but w/o a signal or other out of band error > communication, I'm not sure how to implement this. You can't without a race. You'd have to poll the hardware before and after every I/O operation to ensure that it was still there. Yick. -- \\ Give a man a fish, and you feed him for a day. \\ Mike Smith \\ Tell him he should learn how to fish himself, \\ msmith@freebsd.org \\ and he'll hate you for a lifetime. \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
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