Date: Wed, 19 Mar 2014 00:51:58 -0700 From: Adrian Chadd <adrian@freebsd.org> To: Warner Losh <imp@bsdimp.com> Cc: "freebsd-embedded@freebsd.org" <freebsd-embedded@freebsd.org> Subject: Re: nand controller - how should one handle controllers that want the command+address bits together? Message-ID: <CAJ-VmokZ4Xx4upMh7BSNJpHhoYCauqLW7xcZwhWVfvLvb6HSjw@mail.gmail.com> In-Reply-To: <5BF1217D-6423-443B-A3AB-1722CDDDAD74@bsdimp.com> References: <CAJ-VmonpUsvXFHMCyH--3S4AEocTjhESCyjp9UmT-w5GyuZmvw@mail.gmail.com> <CAJ-VmomM=8M420-LC0z1CoZcz%2BjRBKx4n31ebtbfWG8_xF4Npw@mail.gmail.com> <5BF1217D-6423-443B-A3AB-1722CDDDAD74@bsdimp.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On 18 March 2014 07:12, Warner Losh <imp@bsdimp.com> wrote: > Because the state machines needed for different NAND types more or > less require the 'low level' interface that we have today. The different > phases in setting up a transaction vary somewhat between the different > types of NAND, and we have no real knowledge of that in the NAND layer > today. It was written 4 years ago when most controllers on the market > did little more than bit-bang and/or module the signals to the NAND since > the interfaces at the time were little more than fancy memory mapped > memory controllers. Right. > I've also been looking towards this area as well, given my recent > NAND history. In fact, I've been putting together a talk for BSDcan > on what needs to be done to make the NAND layer sane, cool and > groovy. I may have to come to bsdcan then. You have a DB120; take a look at the ar934x-nfc.c code in openwrt and see what they do. There's apparently a PIO mechanism. It's unclear how to use it and honestly I wouldn't want to. -a
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAJ-VmokZ4Xx4upMh7BSNJpHhoYCauqLW7xcZwhWVfvLvb6HSjw>