From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6DB0C433ED for ; Wed, 12 May 2021 15:15:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E72361956 for ; Wed, 12 May 2021 15:15:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234404AbhELPQr (ORCPT ); Wed, 12 May 2021 11:16:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:38862 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233001AbhELPHD (ORCPT ); Wed, 12 May 2021 11:07:03 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 272C261447; Wed, 12 May 2021 15:01:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1620831684; bh=eVJIJPQRut7K9Tu8mkfXxVF3G+ycqC5k1sE42YbMqek=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=c/0LG8JRxfEogycKZwPikQR2FSRaY8mYTVNlj0kpvzGT4vBoJazp+qHlrCrKRiYyS szXytK/8Kd2+8YxKYesZ2j+TTsP1xWg+l7Ljb+6oUhgWb59z4iOmC7yIR1MmgNA2BG WiDhShGGqolDFtrTLlToBMa9r8Bp1h5JDg+ZI3B7CfZlj8Q15rKIHL4WRoEk8d8YZs lND2A3hZlX0yZgZGuAY06l5+/BYeaaclG55FuVDCoYB//vIYbfcDNfUD2N7Mv+PPwm ebd115sfs2YX9WF5Sw8Lf+XpOFHPx4jJPV+18kiJ2yDnoNiOhPRfd3Bll6z9GfsFuz CcG+OwV8n7Z9g== Date: Wed, 12 May 2021 17:01:18 +0200 From: "wsa@kernel.org" To: Joakim Tjernlund Cc: "andy.shevchenko@gmail.com" , "andriy.shevchenko@linux.intel.com" , "mpe@ellerman.id.au" , "Chris.Packham@alliedtelesis.co.nz" , "robh+dt@kernel.org" , "linuxppc-dev@lists.ozlabs.org" , "devicetree@vger.kernel.org" , "linux-i2c@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v3 0/4] P2040/P2041 i2c recovery erratum Message-ID: <20210512150118.GA1004@ninjato> References: <20210511212052.27242-1-chris.packham@alliedtelesis.co.nz> <4e96247275d559bab133d6c318276fa6be4d7be0.camel@infinera.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="pWyiEgJYm5f9v55/" Content-Disposition: inline In-Reply-To: <4e96247275d559bab133d6c318276fa6be4d7be0.camel@infinera.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --pWyiEgJYm5f9v55/ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > > I've been doing my recent work with a P2040 and prior to that I did tes= t=20 > > out the recovery on a T2081 (which isn't documented to have this=20 > > erratum) when I was re-working the driver. The "new" recovery actually= =20 > > seems better but I don't have a reliably faulty i2c device so that's=20 > > only based on me writing some code to manually trigger the recovery=20 > > (using the snippet below) and observing it with an oscilloscope. >=20 > You don't need a faulty device, just an aborted I2C read/write op. If you can wire GPIOs to the bus, you can use the I2C fault injector: Documentation/i2c/gpio-fault-injection.rst There are already two "incomplete transfer" injectors. --pWyiEgJYm5f9v55/ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmCb7boACgkQFA3kzBSg KbZ2cA/6ArsdZ8oeQnb4ZdE6P2n/iEJan1gFTBse4voG84wLXndcRs9ylZRRy6gU kn+ZRsP8i3eRyJrYHd4a5s9IAfxYlOplIm6VvNLQRe7sMsjNkIxYdCQPwqUA02wy 1jrYOPhAFBnggzP6k5eTtvnf2k9yuma2hJtvu3tzaBs8x0eSx/LEu+K74mPFTkys nmRI2IbgXxkhLw9eVP652bqPkX/kkT2oiABwMw9m9m2qv4Ce/VflEYPq/Ie+9gIt ktbAg/E9UlGMQMzhPZQ0trOdstvXU3U7gD9RoCSnJiUjJaDM2iBtWfM07V86Pptf VOKjbWR2POER3llDyDxdkNVW1bUFh38zprWRkDfQd9pD+F63pTrcwo+iKwST0Lc0 BLGWw1OElr3IaXHSI/bCMtgpUQxplq5unc/+bXydd/DvIw1X0/f0dJMihjbHDYy1 fXa1Ac7plZGHxEdrt4wRLimgjoA/A0eOC1Ixkoc7pKylUjAdOlA7mC7O5tcJ2fg9 p0CuWascBRY/F+UEAtI10Fc9E5q/uLrmmWUPtIvivm+wQx8frIeZS002yeArsvvR +J4NQRv9VPbg+sgDxtX2AHJZnGsKJ22+htHkHE4RfkiNUYEzjNgYwAjd+Fu/cMOw 0tj3LuG1uhYsmHwVwdLC2/MwNh3qVGL1/rbp5aFICBDcF6EZ5D0= =ar4h -----END PGP SIGNATURE----- --pWyiEgJYm5f9v55/-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8D9C4C43460 for ; Wed, 12 May 2021 15:01:58 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B9E5761964 for ; Wed, 12 May 2021 15:01:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B9E5761964 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4FgJ0h02M4z307T for ; Thu, 13 May 2021 01:01:56 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=c/0LG8JR; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=wsa@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=c/0LG8JR; dkim-atps=neutral Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4FgJ085Zpyz2y07 for ; Thu, 13 May 2021 01:01:28 +1000 (AEST) Received: by mail.kernel.org (Postfix) with ESMTPSA id 272C261447; Wed, 12 May 2021 15:01:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1620831684; bh=eVJIJPQRut7K9Tu8mkfXxVF3G+ycqC5k1sE42YbMqek=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=c/0LG8JRxfEogycKZwPikQR2FSRaY8mYTVNlj0kpvzGT4vBoJazp+qHlrCrKRiYyS szXytK/8Kd2+8YxKYesZ2j+TTsP1xWg+l7Ljb+6oUhgWb59z4iOmC7yIR1MmgNA2BG WiDhShGGqolDFtrTLlToBMa9r8Bp1h5JDg+ZI3B7CfZlj8Q15rKIHL4WRoEk8d8YZs lND2A3hZlX0yZgZGuAY06l5+/BYeaaclG55FuVDCoYB//vIYbfcDNfUD2N7Mv+PPwm ebd115sfs2YX9WF5Sw8Lf+XpOFHPx4jJPV+18kiJ2yDnoNiOhPRfd3Bll6z9GfsFuz CcG+OwV8n7Z9g== Date: Wed, 12 May 2021 17:01:18 +0200 From: "wsa@kernel.org" To: Joakim Tjernlund Subject: Re: [PATCH v3 0/4] P2040/P2041 i2c recovery erratum Message-ID: <20210512150118.GA1004@ninjato> References: <20210511212052.27242-1-chris.packham@alliedtelesis.co.nz> <4e96247275d559bab133d6c318276fa6be4d7be0.camel@infinera.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="pWyiEgJYm5f9v55/" Content-Disposition: inline In-Reply-To: <4e96247275d559bab133d6c318276fa6be4d7be0.camel@infinera.com> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "andy.shevchenko@gmail.com" , "robh+dt@kernel.org" , "linux-i2c@vger.kernel.org" , "Chris.Packham@alliedtelesis.co.nz" , "andriy.shevchenko@linux.intel.com" , "linuxppc-dev@lists.ozlabs.org" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" --pWyiEgJYm5f9v55/ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > > I've been doing my recent work with a P2040 and prior to that I did tes= t=20 > > out the recovery on a T2081 (which isn't documented to have this=20 > > erratum) when I was re-working the driver. The "new" recovery actually= =20 > > seems better but I don't have a reliably faulty i2c device so that's=20 > > only based on me writing some code to manually trigger the recovery=20 > > (using the snippet below) and observing it with an oscilloscope. >=20 > You don't need a faulty device, just an aborted I2C read/write op. If you can wire GPIOs to the bus, you can use the I2C fault injector: Documentation/i2c/gpio-fault-injection.rst There are already two "incomplete transfer" injectors. --pWyiEgJYm5f9v55/ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmCb7boACgkQFA3kzBSg KbZ2cA/6ArsdZ8oeQnb4ZdE6P2n/iEJan1gFTBse4voG84wLXndcRs9ylZRRy6gU kn+ZRsP8i3eRyJrYHd4a5s9IAfxYlOplIm6VvNLQRe7sMsjNkIxYdCQPwqUA02wy 1jrYOPhAFBnggzP6k5eTtvnf2k9yuma2hJtvu3tzaBs8x0eSx/LEu+K74mPFTkys nmRI2IbgXxkhLw9eVP652bqPkX/kkT2oiABwMw9m9m2qv4Ce/VflEYPq/Ie+9gIt ktbAg/E9UlGMQMzhPZQ0trOdstvXU3U7gD9RoCSnJiUjJaDM2iBtWfM07V86Pptf VOKjbWR2POER3llDyDxdkNVW1bUFh38zprWRkDfQd9pD+F63pTrcwo+iKwST0Lc0 BLGWw1OElr3IaXHSI/bCMtgpUQxplq5unc/+bXydd/DvIw1X0/f0dJMihjbHDYy1 fXa1Ac7plZGHxEdrt4wRLimgjoA/A0eOC1Ixkoc7pKylUjAdOlA7mC7O5tcJ2fg9 p0CuWascBRY/F+UEAtI10Fc9E5q/uLrmmWUPtIvivm+wQx8frIeZS002yeArsvvR +J4NQRv9VPbg+sgDxtX2AHJZnGsKJ22+htHkHE4RfkiNUYEzjNgYwAjd+Fu/cMOw 0tj3LuG1uhYsmHwVwdLC2/MwNh3qVGL1/rbp5aFICBDcF6EZ5D0= =ar4h -----END PGP SIGNATURE----- --pWyiEgJYm5f9v55/--