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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 82191C4332F for ; Sat, 21 May 2022 13:00:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243619AbiEUNAz (ORCPT ); Sat, 21 May 2022 09:00:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38068 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234385AbiEUNAu (ORCPT ); Sat, 21 May 2022 09:00:50 -0400 Received: from mail-vs1-xe36.google.com (mail-vs1-xe36.google.com [IPv6:2607:f8b0:4864:20::e36]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 977C3E6A; Sat, 21 May 2022 06:00:47 -0700 (PDT) Received: by mail-vs1-xe36.google.com with SMTP id c62so10677789vsc.10; Sat, 21 May 2022 06:00:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=UiYBOOmE3B2tSMcIdam7Gz2hPUtw38sVw9m7ntvwfEA=; b=dLYTDccXOF5vdOcM3oYWeoDuEOe54vEE4MBQ4R2N4kJ0igBgtDxgjrcTmNno4/JYpU GCcDVEj5y1Xd0mFpJDTzwQCRcc0Fun+V4xGU8tybudQaPobtD5MQSknBJG47m9O4JNdY RNonrsVcOwvBn7VZuvbazM4jE5m7PTDXznBFyXxXo4Brvh0SfIDMeXLIqfMo9OKuUctn ksOd1CzhjJgaHIjm0ignljw8gatzaoNQmF8dL4/dPq+gSRntJCICTh3IOA9G5vElMjHR 3jNsWJNJxDPlHyHne+ed8UIlgrT9eGAj2yIfLGO9hj900vbevMKLkh6CsUxU5SXc5GZ8 ZXIg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=UiYBOOmE3B2tSMcIdam7Gz2hPUtw38sVw9m7ntvwfEA=; b=RSpOn5mlzVaOZDXszF+Fpoap8GVLpwfNafZjze4jvidQf2MOIh+Ce67qK1kXXlTV65 0nH2m/exgZq4kCIKcLvrpQA8zJCI9oaPC5jLr73tTO/mewp09iEP9PMwMIorslF1x4+s BYUymhBsouq80KP5O9xGniq9/Jh+X5bzuwcKh18hgz9LEfaSei50puIeJsqe3oNF5cWd 4RR7eIU1DUdlE/IPIfaYxL5El0bb390BoNexzucwgBd3BUe4qWVZlB0Tr9mg91Xblhif IemLMj6hRfWxFOOSjPjXEooBfxRBTsMq834OWMoIRad2j0Ltx5GAUFeQFLO2SNia5SpO pAEg== X-Gm-Message-State: AOAM530hKDtlucu6Hi3zZdc8BZ9042HO0ywTOEBsBks2EBzjG5XBfTnM WvbY+LD2m5TTySU7KZM6791SRHRk3GDXUttk54qr3HSwCPJK X-Google-Smtp-Source: ABdhPJwsVewjsXSGmqYnvos4AOWRr7OMnGYmuogma9c6Tmg7y3vgxiG6y6zNx3QmQQ8Cb58ZOP81bncQx7cAkIryqDk= X-Received: by 2002:a67:d88c:0:b0:337:9a25:36c3 with SMTP id f12-20020a67d88c000000b003379a2536c3mr818585vsj.84.1653138046685; Sat, 21 May 2022 06:00:46 -0700 (PDT) MIME-Version: 1.0 References: <20220517101142.28421-1-warp5tw@gmail.com> <20220517101142.28421-8-warp5tw@gmail.com> In-Reply-To: From: Tyrone Ting Date: Sat, 21 May 2022 21:00:35 +0800 Message-ID: Subject: Re: [PATCH v5 07/10] i2c: npcm: Handle spurious interrupts To: Wolfram Sang , Tyrone Ting , avifishman70@gmail.com, tmaimon77@gmail.com, tali.perry1@gmail.com, venture@google.com, yuenn@google.com, benjaminfair@google.com, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, andriy.shevchenko@linux.intel.com, jarkko.nikula@linux.intel.com, semen.protsenko@linaro.org, rafal@milecki.pl, sven@svenpeter.dev, jsd@semihalf.com, lukas.bulwahn@gmail.com, arnd@arndb.de, olof@lixom.net, tali.perry@nuvoton.com, Avi.Fishman@nuvoton.com, tomer.maimon@nuvoton.com, KWLIU@nuvoton.com, JJLIU0@nuvoton.com, kfting@nuvoton.com, openbmc@lists.ozlabs.org, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Cc: jie.deng@intel.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Wolfram: Thank you for your review. Wolfram Sang =E6=96=BC 2022=E5=B9=B45=E6=9C=8821=E6=97=A5 = =E9=80=B1=E5=85=AD =E4=B8=8B=E5=8D=881:53=E5=AF=AB=E9=81=93=EF=BC=9A > > On Tue, May 17, 2022 at 06:11:39PM +0800, Tyrone Ting wrote: > > From: Tali Perry > > > > On some platforms in rare cases (1 to 100,000 transactions), > > the i2c gets a spurious interrupt which means that we enter an interrup= t > > but in the interrupt handler we don't find any status bit that points t= o > > the reason we got this interrupt. > > > > This may be a case of a rare HW issue or signal integrity issue that is > > still under investigation. > > > > In order to overcome this we are doing the following: > > 1. Disable incoming interrupts in master mode only when slave mode is n= ot > > enabled. > > 2. Clear end of busy (EOB) after every interrupt. > > 3. Clear other status bits (just in case since we found them cleared) > > 4. Return correct status during the interrupt that will finish the > > transaction. > > > > On next xmit transaction if the bus is still busy the master will issue= a > > recovery process before issuing the new transaction. > > > > Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller dri= ver") > > Signed-off-by: Tali Perry > > Signed-off-by: Tyrone Ting > > Applied to for-next, thanks! > Best Regards, Tyrone