From owner-freebsd-embedded@FreeBSD.ORG Wed Mar 19 15:07:11 2014 Return-Path: Delivered-To: freebsd-embedded@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 56D1BE08 for ; Wed, 19 Mar 2014 15:07:11 +0000 (UTC) Received: from mail-pa0-f50.google.com (mail-pa0-f50.google.com [209.85.220.50]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 26E46262 for ; Wed, 19 Mar 2014 15:07:10 +0000 (UTC) Received: by mail-pa0-f50.google.com with SMTP id kq14so9127430pab.9 for ; Wed, 19 Mar 2014 08:07:10 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:sender:content-type:mime-version:subject:from :in-reply-to:date:cc:content-transfer-encoding:message-id:references :to; bh=Z4fVQowOcrCOQTOBworxY+6C6jT8BFL1YjlQ+DJk/lI=; b=UBuHkPTDcehHdN9YiWs3JL4mufu4nncv/4RXe7oRrGnvw667/Px2aX3fNPZh8IH1Qt vMfdVVUomyAyl7a5QyOV8V5b4d6ON5MdImu5aL+A38UqWvB4jNcXTmNNcs7CMtZ9yAP+ h2DpVRcWX1EvEbOhpKk/9+tA20DrvOlTZbVlbVx0hafAQmw6ZNC6aCjJgED4e20cHe4+ t73KdKi2V+mXvvDD9qLXmc7r2Jk2OuoJZZWVmQIfcw4c2DAnRkAdVBVaUYPpHdCK7JNb MfH9kcYDkIm99qMmOJCDQUsgylzHiqEk5O8Arivcw3KbsmRGr4W/VJ+psFZEx7P8Yryt MssQ== X-Gm-Message-State: ALoCoQlTyW0g02ie754BK0QK0VxhCLdla2Z+BNolUMRfk8/3TXkX72h0sno/7JAfkviRlGNlG+t6 X-Received: by 10.68.201.10 with SMTP id jw10mr40449754pbc.25.1395241630274; Wed, 19 Mar 2014 08:07:10 -0700 (PDT) Received: from bsdimp.corp.netflix.com ([69.53.237.72]) by mx.google.com with ESMTPSA id vd8sm11865677pac.12.2014.03.19.08.06.22 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 19 Mar 2014 08:06:31 -0700 (PDT) Sender: Warner Losh Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.2 \(1874\)) Subject: Re: nand controller - how should one handle controllers that want the command+address bits together? From: Warner Losh In-Reply-To: Date: Wed, 19 Mar 2014 08:06:11 -0700 Content-Transfer-Encoding: quoted-printable Message-Id: <72D01ACF-F827-48E7-82DF-6728E5FC24EE@bsdimp.com> References: <5BF1217D-6423-443B-A3AB-1722CDDDAD74@bsdimp.com> To: Adrian Chadd X-Mailer: Apple Mail (2.1874) Cc: "freebsd-embedded@freebsd.org" X-BeenThere: freebsd-embedded@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Dedicated and Embedded Systems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 Mar 2014 15:07:11 -0000 On Mar 19, 2014, at 12:51 AM, Adrian Chadd wrote: > On 18 March 2014 07:12, Warner Losh wrote: >=20 >> 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. >=20 > Right. >=20 >=20 >> 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. >=20 > I may have to come to bsdcan then. >=20 > You have a DB120; take a look at the ar934x-nfc.c code in openwrt and > see what they do. OK. > There's apparently a PIO mechanism. It's unclear how to use it and > honestly I wouldn't want to. I=92ll give it a look when I climb back into the NAND world here next = week or so (I was planning on being somewhat specific in my talk at BSDcan, so need to re-review my notes I=92ve taken so far). I=92ll see if I can get = you early access to my talk (meaning, I=92ll see if I can finish early :). Warner