Date: Wed, 6 May 1998 10:43:29 -0600 (MDT) From: Nate Williams <nate@mt.sri.com> To: Amancio Hasty <hasty@rah.star-gate.com> Cc: Nate Williams <nate@mt.sri.com>, Mike Smith <mike@smith.net.au>, Archie Cobbs <archie@whistle.com>, stefan@promo.de (Stefan Bethke), luigi@labinfo.iet.unipi.it, freebsd-hackers@FreeBSD.ORG Subject: Re: ISA-PnP w\o BIOS support? Message-ID: <199805061643.KAA16376@fly.mt.sri.com> In-Reply-To: <199805061638.JAA08371@rah.star-gate.com> References: <199805061517.JAA05337@mt.sri.com> <199805061638.JAA08371@rah.star-gate.com>
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> The device driver can tell the upper layer which resources it wants or > does not need. The device driver needs a hint from the user to know whether or not it wants a resource or not. For example, some PCIC controllers don't correctly interrupt when cards are removed/inserted. In this case, we still assign an IRQ to the controller, although all we're doing is wasting an interrupt. Instead of assigning an interrupt, we should simply 'poll' the controller for events, which doesn't work as well *but* still allows the hardware to work. However, the FreeBSD kernel can't determine if the controller is working, so we need a way for the controller probe to be given 'hints' as to whether or not to use an IRQ, and if so a good one to try. The latter is needed because some 'internal' hardware is hidden from the kernel, so if I use the first free interrupt it *may* not be correct for this configuration, so I must tell it which interrupt to use if I want to be safe. In other words, the device driver does *NOT* have enough information to do it's job, hence the current model is incomplete. Nate To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
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