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=-4.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, PDS_BAD_THREAD_QP_64,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 75068C433B4 for ; Thu, 20 May 2021 03:37:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4FB7161184 for ; Thu, 20 May 2021 03:37:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230262AbhETDiX (ORCPT ); Wed, 19 May 2021 23:38:23 -0400 Received: from gate2.alliedtelesis.co.nz ([202.36.163.20]:33105 "EHLO gate2.alliedtelesis.co.nz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229598AbhETDiW (ORCPT ); Wed, 19 May 2021 23:38:22 -0400 Received: from svr-chch-seg1.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id 194CF84487; Thu, 20 May 2021 15:36:59 +1200 (NZST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alliedtelesis.co.nz; s=mail181024; t=1621481819; bh=VRbO4+naf38qOxw5jDMURFAeVwM1Gn4WAr6oIe/Om1Q=; h=From:To:CC:Subject:Date:References:In-Reply-To; b=IvlORQazLNUXOxWwca6w0GSF/LVUilQq1KeoC5OsjkvkYhSWiohrXByKd4bikWAoc puuOF8foJdJQiD/ZFbzhVtPz5B23V25hX64edzsVFw/oiwh8zrTG9+PufAKpOB4RRQ ZO6Rux5xpqjxYL0lsCgVDh7K/yvuKhF4RnCJF0C4qa12ScAiMh/YrUzzgQugFHui+9 Nj2kwGDRTR4VtYg+D9vHPpBJuP5GlCZPemxCWr1q6T9QNpqnXRZCW5xJdy7bNUyj9K BUgYQtUhHZaCxuQpnRodTXWeXWKIb2BSj9fp5VvuVfTNn+OhZgVvfnGsPTHVpLF1hK JRkX8tLfRX1hg== Received: from svr-chch-ex1.atlnz.lc (Not Verified[2001:df5:b000:bc8::77]) by svr-chch-seg1.atlnz.lc with Trustwave SEG (v8,2,6,11305) id ; Thu, 20 May 2021 15:36:59 +1200 Received: from svr-chch-ex1.atlnz.lc (2001:df5:b000:bc8:409d:36f5:8899:92e8) by svr-chch-ex1.atlnz.lc (2001:df5:b000:bc8:409d:36f5:8899:92e8) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Thu, 20 May 2021 15:36:58 +1200 Received: from svr-chch-ex1.atlnz.lc ([fe80::409d:36f5:8899:92e8]) by svr-chch-ex1.atlnz.lc ([fe80::409d:36f5:8899:92e8%12]) with mapi id 15.00.1497.018; Thu, 20 May 2021 15:36:58 +1200 From: Chris Packham To: "wsa@kernel.org" , Joakim Tjernlund CC: "andy.shevchenko@gmail.com" , "andriy.shevchenko@linux.intel.com" , "mpe@ellerman.id.au" , "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 Thread-Topic: [PATCH v3 0/4] P2040/P2041 i2c recovery erratum Thread-Index: AQHXRquHhXA6XgnPF0OPgP79h3OVQ6reDlyAgAA9BACAAHfVAIAAZZwAgAvTcoA= Date: Thu, 20 May 2021 03:36:58 +0000 Message-ID: References: <20210511212052.27242-1-chris.packham@alliedtelesis.co.nz>

<4e96247275d559bab133d6c318276fa6be4d7be0.camel@infinera.com> <20210512150118.GA1004@ninjato> In-Reply-To: <20210512150118.GA1004@ninjato> Accept-Language: en-NZ, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.32.1.11] Content-Type: text/plain; charset="Windows-1252" Content-ID: <458C7B1C38153849A89C7527D57D2E44@atlnz.lc> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-SEG-SpamProfiler-Analysis: v=2.3 cv=WOcBoUkR c=1 sm=1 tr=0 a=Xf/6aR1Nyvzi7BryhOrcLQ==:117 a=xqWC_Br6kY4A:10 a=oKJsc7D3gJEA:10 a=N659UExz7-8A:10 a=5FLXtPjwQuUA:10 a=VwQbUJbxAAAA:8 a=T-qbRSzZqTrywjUDPykA:9 a=pILNOxqGKmIA:10 a=AjGcO6oz07-iQ99wixmX:22 X-SEG-SpamProfiler-Score: 0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 13/05/21 3:01 am, wsa@kernel.org wrote: >>> I've been doing my recent work with a P2040 and prior to that I did tes= t >>> out the recovery on a T2081 (which isn't documented to have this >>> erratum) when I was re-working the driver. The "new" recovery actually >>> seems better but I don't have a reliably faulty i2c device so that's >>> only based on me writing some code to manually trigger the recovery >>> (using the snippet below) and observing it with an oscilloscope. >> 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. > Just giving this thread a poke. I have been looking at my options for=20 triggering an i2c recovery but haven't really had time to do much. I=20 think the best option given what I've got access to is a modified SFP=20 that grounds the SDA line but I need to find a system where I can attach=20 an oscilloscope (should be a few of these in the office when I can get=20 on-site). I can confirm that when manually triggered the existing recovery and the=20 new erratum workaround produce what I'd expect to observe on an=20 oscilloscope. I haven't explored Joakim's alternative recovery but I don't think that=20 should hold up these changes, any improvement to the existing recovery=20 can be done later as a follow-up. 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=-2.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, PDS_BAD_THREAD_QP_64,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 D3D31C433B4 for ; Thu, 20 May 2021 03:37:41 +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 0187B61184 for ; Thu, 20 May 2021 03:37:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0187B61184 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=alliedtelesis.co.nz 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 4FlwRR56cyz3082 for ; Thu, 20 May 2021 13:37:39 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=alliedtelesis.co.nz header.i=@alliedtelesis.co.nz header.a=rsa-sha256 header.s=mail181024 header.b=IvlORQaz; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=alliedtelesis.co.nz (client-ip=202.36.163.20; helo=gate2.alliedtelesis.co.nz; envelope-from=chris.packham@alliedtelesis.co.nz; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=alliedtelesis.co.nz header.i=@alliedtelesis.co.nz header.a=rsa-sha256 header.s=mail181024 header.b=IvlORQaz; dkim-atps=neutral Received: from gate2.alliedtelesis.co.nz (gate2.alliedtelesis.co.nz [202.36.163.20]) (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 4FlwQt38Bfz2xYZ for ; Thu, 20 May 2021 13:37:10 +1000 (AEST) Received: from svr-chch-seg1.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id 12209806B6; Thu, 20 May 2021 15:36:59 +1200 (NZST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alliedtelesis.co.nz; s=mail181024; t=1621481819; bh=VRbO4+naf38qOxw5jDMURFAeVwM1Gn4WAr6oIe/Om1Q=; h=From:To:CC:Subject:Date:References:In-Reply-To; b=IvlORQazLNUXOxWwca6w0GSF/LVUilQq1KeoC5OsjkvkYhSWiohrXByKd4bikWAoc puuOF8foJdJQiD/ZFbzhVtPz5B23V25hX64edzsVFw/oiwh8zrTG9+PufAKpOB4RRQ ZO6Rux5xpqjxYL0lsCgVDh7K/yvuKhF4RnCJF0C4qa12ScAiMh/YrUzzgQugFHui+9 Nj2kwGDRTR4VtYg+D9vHPpBJuP5GlCZPemxCWr1q6T9QNpqnXRZCW5xJdy7bNUyj9K BUgYQtUhHZaCxuQpnRodTXWeXWKIb2BSj9fp5VvuVfTNn+OhZgVvfnGsPTHVpLF1hK JRkX8tLfRX1hg== Received: from svr-chch-ex1.atlnz.lc (Not Verified[2001:df5:b000:bc8::77]) by svr-chch-seg1.atlnz.lc with Trustwave SEG (v8, 2, 6, 11305) id ; Thu, 20 May 2021 15:36:58 +1200 Received: from svr-chch-ex1.atlnz.lc (2001:df5:b000:bc8:409d:36f5:8899:92e8) by svr-chch-ex1.atlnz.lc (2001:df5:b000:bc8:409d:36f5:8899:92e8) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Thu, 20 May 2021 15:36:58 +1200 Received: from svr-chch-ex1.atlnz.lc ([fe80::409d:36f5:8899:92e8]) by svr-chch-ex1.atlnz.lc ([fe80::409d:36f5:8899:92e8%12]) with mapi id 15.00.1497.018; Thu, 20 May 2021 15:36:58 +1200 From: Chris Packham To: "wsa@kernel.org" , Joakim Tjernlund Subject: Re: [PATCH v3 0/4] P2040/P2041 i2c recovery erratum Thread-Topic: [PATCH v3 0/4] P2040/P2041 i2c recovery erratum Thread-Index: AQHXRquHhXA6XgnPF0OPgP79h3OVQ6reDlyAgAA9BACAAHfVAIAAZZwAgAvTcoA= Date: Thu, 20 May 2021 03:36:58 +0000 Message-ID: References: <20210511212052.27242-1-chris.packham@alliedtelesis.co.nz>