Date: Sun, 6 Dec 2009 12:51:19 +0100 From: Roman Divacky <rdivacky@FreeBSD.org> To: Alexander Motin <mav@FreeBSD.org> Cc: svn-src-head@FreeBSD.org, svn-src-all@FreeBSD.org, src-committers@FreeBSD.org Subject: Re: svn commit: r200171 - in head: sbin/atacontrol sys/arm/mv sys/cam/ata sys/cam/scsi sys/conf sys/dev/ata sys/dev/ata/chipsets sys/powerpc/powermac sys/powerpc/psim Message-ID: <20091206115119.GA25721@freebsd.org> In-Reply-To: <200912060010.nB60AD12004058@svn.freebsd.org> References: <200912060010.nB60AD12004058@svn.freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sun, Dec 06, 2009 at 12:10:13AM +0000, Alexander Motin wrote: > Author: mav > Date: Sun Dec 6 00:10:13 2009 > New Revision: 200171 > URL: http://svn.freebsd.org/changeset/base/200171 > > Log: > MFp4: > Introduce ATA_CAM kernel option, turning ata(4) controller drivers into > cam(4) interface modules. When enabled, this options deprecates all ata(4) > peripheral drivers (ad, acd, ...) and interfaces and allows cam(4) drivers > (ada, cd, ...) and interfaces to be natively used instead. > > As side effect of this, ata(4) mode setting code was completely rewritten > to make controller API more strict and permit above change. While doing > this, SATA revision was separated from PATA mode. It allows DMA-incapable > SATA devices to operate and makes hw.ata.atapi_dma tunable work again. > > Also allow ata(4) controller drivers (except some specific or broken ones) > to handle larger data transfers. Previous constraint of 64K was artificial > and is not really required by PCI ATA BM specification or hardware. are there any performance benefits of the 64K limit removal?
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20091206115119.GA25721>