Date: Mon, 28 Oct 2002 01:11:05 +0000 From: Ian Dowse <iedowse@maths.tcd.ie> To: "M. Warner Losh" <imp@bsdimp.com> Cc: freebsd-mobile@FreeBSD.ORG Subject: Re: Patch to fix/shorten "wi" freezes Message-ID: <200210280111.aa16990@salmon.maths.tcd.ie> In-Reply-To: Your message of "Sun, 27 Oct 2002 17:06:46 MST." <20021027.170646.118304063.imp@bsdimp.com>
next in thread | previous in thread | raw e-mail | index | archive | help
In message <20021027.170646.118304063.imp@bsdimp.com>, "M. Warner Losh" writes:
>
>For the removal, it would be better to use the bus_child_present() api
>for the eject case.
Does the pccard system implement bus_child_present()? I just did a
quick grep for *_child_present there without finding anything, but
maybe I'm looking for the wrong thing. Is the idea to use something
like
if (sc->wi_gone)
return;
<hardware operation>
if (timeout) {
if (!bus_child_present(sc->dev)) {
sc->wi_gone = 1;
return;
}
device_printf(sc->dev, "device timeout\n");
}
so that further slow timeouts can be avoided if the device has
really been removed? I presume it is too much overhead to just call
bus_child_present() everywhere instead of testing `gone'.
>For the hardware becomes confused case, setting
>gone means that nothing further will happen with the card. However,
>the other parts of this patch seem relatively reasonable to me.
Yes, this is a problem if some devices report errors and then come
back to life. The problems I have seen don't recover, but I guess
that will not always be the case. In the patch the `gone' flag is
set when status is 0xffff after a timeout and when the "busy bit
won't clear" error occurs. Hopefully these are both usually cases
where the hardware does not recover itself.
Ian
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-mobile" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200210280111.aa16990>