From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kumba Date: Fri, 29 Jul 2005 02:16:28 +0000 Subject: Re: fd0 not found Message-Id: <42E9917C.3080000@gentoo.org> List-Id: References: <42E61753.8050502@cpttm.org.mo> In-Reply-To: <42E61753.8050502@cpttm.org.mo> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: sparclinux@vger.kernel.org David S. Miller wrote: > > It's not a matter of detection, it's working around the brain damaged > design of this thing. > > The floppy device wants to do ISA DMA, but on the ISA bus it is > illegal for other agents to issue ISA I/O port operations while a DMA > is in progress. The ISA bus has a signal that the processor is > supposed to use to determine when DMA is in progress and thus I/O port > operations cannot be initiated, but there is no hookup for this to the > UltraSPARC chip in the SB100. > > Thus the only way to handle this is to make the current thread of > execution sleep if it tries to do an I/O port access while a floppy > DMA is in progress, and since we can't sleep in interrupt handler > context there is no way to implement this awefully gross workaround > for hardware mis-design. > > Just get a USB memory stick if you want small portable storage. > The floppy device on the SB100 is unlikely to ever be supported. I don't suppose any of the kludges found in OpenSolaris code are portable into linux sources to address some of the design flaws/oddities? (Portable meaning license friendly, etc..) --Kumba -- Gentoo/MIPS Team Lead Gentoo Foundation Board of Trustees "Such is oft the course of deeds that move the wheels of the world: small hands do them because they must, while the eyes of the great are elsewhere." --Elrond