From owner-freebsd-arm@freebsd.org Sun May 31 19:57:08 2020 Return-Path: Delivered-To: freebsd-arm@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id A38CE33F90D for ; Sun, 31 May 2020 19:57:08 +0000 (UTC) (envelope-from freebsd@cyclaero.com) Received: from mo4-p00-ob.smtp.rzone.de (mo4-p00-ob.smtp.rzone.de [81.169.146.219]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "*.smtp.rzone.de", Issuer "TeleSec ServerPass Class 2 CA" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 49Zpwz0xsgz3Y2v; Sun, 31 May 2020 19:57:06 +0000 (UTC) (envelope-from freebsd@cyclaero.com) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1590955024; s=strato-dkim-0002; d=cyclaero.com; h=To:References:Message-Id:Cc:Date:In-Reply-To:From:Subject: X-RZG-CLASS-ID:X-RZG-AUTH:From:Subject:Sender; bh=qXgXJarJqIQXnvZZ/RAJobKbag7mlgZ1IqTNxVootXk=; b=Q4lAufp0Wf0F09QrV24N4/iwpTjkm0++KN5VXQdror6rLI9soJg+IngpnklmCwcbpm fVIs8KMTytxctpfo2D1VNfQtvlli0eS5ggJFXAQ7aNsm9bqheeIt5vKgNj0RV5RqkPkq DccwkXGmPhD3WeYIeka0tdGEtzohPehNecBOqemPE6u0Xv153ACkPGvFz5opkuTctUPt Gw3vJvFzuVcqvgnNqCew2SSt7CDVou2yQGDhXdBIL3dgwHxlEhchG94Y0wU3WlkLGmpD v8a2mKowdsq9S0hfy+F2VL7P7sZZxNPSo39jwOUIB+zBJ0EDF4cG/9bDEvHpqhg1QSwe pdGw== X-RZG-AUTH: ":O2kGeEG7b/pS1F2rRHW2isrKl4DV03XBEi+I6ZuztdvN9wS3wFGySS4Lw+ldTBio0dVbInGjc9PbZFAm0A==" X-RZG-CLASS-ID: mo00 Received: from mail.obsigna.com by smtp.strato.de (RZmta 46.9.0 DYNA|AUTH) with ESMTPSA id I06cf5w4VJv3Apl (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits)) (Client did not present a certificate); Sun, 31 May 2020 21:57:03 +0200 (CEST) Received: from rolf-mini.obsigna.com (rolf-mini.obsigna.com [192.168.222.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.obsigna.com (Postfix) with ESMTPSA id 6D3811350F91D; Sun, 31 May 2020 16:57:00 -0300 (-03) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\)) Subject: Re: BeagleBone AI From: "Dr. Rolf Jansen" In-Reply-To: <966c33ea1924c2cfab5d9e295a9239d134e03f8a.camel@freebsd.org> Date: Sun, 31 May 2020 16:56:58 -0300 Cc: freebsd-arm@freebsd.org Content-Transfer-Encoding: quoted-printable Message-Id: <3CA84BA5-FEA8-4BD8-A713-C794139170EE@cyclaero.com> References: <966c33ea1924c2cfab5d9e295a9239d134e03f8a.camel@freebsd.org> To: Ian Lepore X-Mailer: Apple Mail (2.3445.104.11) X-Rspamd-Queue-Id: 49Zpwz0xsgz3Y2v X-Spamd-Bar: / Authentication-Results: mx1.freebsd.org; dkim=pass header.d=cyclaero.com header.s=strato-dkim-0002 header.b=Q4lAufp0; dmarc=none; spf=pass (mx1.freebsd.org: domain of freebsd@cyclaero.com designates 81.169.146.219 as permitted sender) smtp.mailfrom=freebsd@cyclaero.com X-Spamd-Result: default: False [-0.77 / 15.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; R_DKIM_ALLOW(-0.20)[cyclaero.com:s=strato-dkim-0002]; NEURAL_HAM_MEDIUM(-1.05)[-1.055]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; MV_CASE(0.50)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; R_SPF_ALLOW(-0.20)[+ip4:81.169.146.128/25]; DMARC_NA(0.00)[cyclaero.com]; RWL_MAILSPIKE_GOOD(0.00)[81.169.146.219:from]; NEURAL_SPAM_SHORT(0.36)[0.364]; NEURAL_HAM_LONG(-0.98)[-0.984]; RCVD_COUNT_THREE(0.00)[3]; DKIM_TRACE(0.00)[cyclaero.com:+]; RCPT_COUNT_TWO(0.00)[2]; FROM_NAME_HAS_TITLE(1.00)[dr]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:6724, ipnet:81.169.144.0/22, country:DE]; RCVD_TLS_ALL(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_IN_DNSWL_LOW(-0.10)[81.169.146.219:from] X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 31 May 2020 19:57:08 -0000 > Am 31.05.2020 um 14:11 schrieb Ian Lepore : >=20 > On Fri, 2020-05-29 at 23:21 -0300, Dr. Rolf Jansen wrote: >> ... >>=20 >> First Question: >>=20 >> What modern SBC with more than 1 I=C2=B2C bus and which can run = FreeBSD 13++ would you suggest? >>=20 >> ... >>=20 >> Two more Questions: >>=20 >> Is it reasonable to assume that FreeBSD would run on a BBAI in the = future, let=E2=80=99s say in 2 to 3 years? >>=20 >> Perhaps I could help porting FreeBSD to a BBAI. What would be the = general steps? >>=20 >>=20 >> Many thanks in advance for any suggestions, advices and = clarifications. >>=20 >> Best regards >>=20 >> Rolf >=20 > BTW, if you need drivers for any new i2c devices just let me know and > I'll see what I can do. I am pretty comfortable with register level programming, and so far I = came away with ioctl() calls for what I needed. So perhaps I won=E2=80=99t= need exactly a driver for new I=C2=B2C devices. However, I am far away = from being a perfect I=C2=B2C expert, specially when it comes to timing = and the best sequence of addressing different devices on the bus. = Perhaps, I may ask some questions when I run into problems. > Also, in my experience you can often get away with running an i2c bus > faster than 400khz if you need more bandwidth. I've never seen any > modern chip fail to work at 800khz, and most seem to work fine up to > about 1mhz; above that they become pretty unreliable. Does this =E2=80=9Eover clocking=E2=80=9C work for the ARM boards as = well? I just set the clock-frequency in the dts-overlay which activates = I2C1 of the BBB from 400000 to 800000. The bus seems to work as usual, = however, I did not yet come to check its speed. How again would I do = that? Probably there are many more questions to come :-) Best regards Rolf=