From owner-freebsd-questions Thu Jun 17 16:29:18 1999 Delivered-To: freebsd-questions@freebsd.org Received: from hyperreal.org (taz.hyperreal.org [209.133.83.16]) by hub.freebsd.org (Postfix) with SMTP id 993EE14C97 for ; Thu, 17 Jun 1999 16:29:13 -0700 (PDT) (envelope-from mike@hyperreal.org) Received: (qmail 29626 invoked by uid 12); 17 Jun 1999 23:29:11 -0000 Message-ID: <19990617232911.29625.qmail@hyperreal.org> From: mike@hyperreal.org Subject: Re: Optimizing IDE performance revisited In-Reply-To: from Alfred Perlstein at "Jun 17, 1999 03:16:46 pm" To: bright@rush.net (Alfred Perlstein) Date: Thu, 17 Jun 1999 16:29:11 -0700 (PDT) Cc: freebsd-questions@freebsd.org X-Mailer: ELM [version 2.4ME+ PL51 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Alfred Perlstein wrote: > > Is there something else that I need to configure in the kernel to enable PIO > > or DMA? > > yes, set your IDE flags to 0xa0ffa0ff , or some subset of that, check > the LINT kernel config file, some machines that don't support DMA will > hang if DMA is enabled, so double check it. Oh, not really understanding what bus-mastering DMA is, I didn't realize that this flag was referring to the same kind of DMA (perhaps if it had made some reference to DMA modes..) 0x2000 Probe for and use the bus-mastering DMA capabilities of modern PCI chipsets. So, 0xb0ffb0ff as I have is fine. (The extra 0x1000 = use LBA). Looking at the driver source, it looks like a "wdc0: DMA failure" message will appear if something goes wrong. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message