From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andreas Schwab Subject: Re: [PATCH v5 3/3] i2c-ocores: sifive: add polling mode workaround for FU540-C000 SoC. Date: Tue, 21 May 2019 10:33:48 +0200 Message-ID: References: <1558361478-4381-1-git-send-email-sagar.kadam@sifive.com> <1558361478-4381-4-git-send-email-sagar.kadam@sifive.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1558361478-4381-4-git-send-email-sagar.kadam@sifive.com> (Sagar Shrikant Kadam's message of "Mon, 20 May 2019 19:41:18 +0530") Sender: linux-kernel-owner@vger.kernel.org To: Sagar Shrikant Kadam Cc: robh+dt@kernel.org, mark.rutland@arm.com, peter@korsgaard.com, andrew@lunn.ch, palmer@sifive.com, paul.walmsley@sifive.com, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org List-Id: linux-i2c@vger.kernel.org On Mai 20 2019, Sagar Shrikant Kadam wrote: > The i2c-ocore driver already has a polling mode interface.But it needs > a workaround for FU540 Chipset on HiFive unleashed board (RevA00). > There is an erratum in FU540 chip that prevents interrupt driven i2c > transfers from working, and also the I2C controller's interrupt bit > cannot be cleared if set, due to this the existing i2c polling mode > interface added in mainline earlier doesn't work, and CPU stall's > infinitely, when-ever i2c transfer is initiated. > > Ref:previous polling mode support in mainline > > commit 69c8c0c0efa8 ("i2c: ocores: add polling interface") > > The workaround / fix under OCORES_FLAG_BROKEN_IRQ is particularly for > FU540-COOO SoC. After commit dd7dbf0eb090 this no longer fits. Andreas. -- Andreas Schwab, SUSE Labs, schwab@suse.de GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 "And now for something completely different." 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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=ham 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 DEA96C04AAF for ; Tue, 21 May 2019 08:34:02 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 B4AFB216B7 for ; Tue, 21 May 2019 08:34:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="rwRsCgki" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B4AFB216B7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+infradead-linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:In-Reply-To: Date:References:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=hkcI7DHQKwbf9s4ilhpmXI4mjpOSbr9kPOuBvjkDfrg=; b=rwRsCgkiaVfS+M z7kiePKP/iBJtoqcgk4Zly0sO2bTNOjOEQtBI9HESfFbcEz/wIbNE3ALh93qtZxpoZWupe6Zi7rba 3tFX+mqbw7KQpdP0wjeWtpWRN/gttWC5z3oLiQl1l5jQm33zjY2T6u5x8SgfRNk2+XcFfbtvlNP1V WJe7s+WN9yR8jEUvMupagaruHLXNKpchHqD4yDCwdDKY3QgqHcBMyQwWzJKncrehjtoN7dV8KtUSc MMiQTqb6owuaRzL7TMyNR7ck2HBPuvbVIQ2Bb2EbTWqdn9j4mIUSPB6JmWmT8D+DY8xSpMsbkESO6 HmTtAUTPugniaHQ841GA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hT0Df-0000vH-5q; Tue, 21 May 2019 08:33:59 +0000 Received: from mx2.suse.de ([195.135.220.15] helo=mx1.suse.de) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hT0DZ-0000jm-70 for linux-riscv@lists.infradead.org; Tue, 21 May 2019 08:33:57 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 7017BAB9D; Tue, 21 May 2019 08:33:50 +0000 (UTC) From: Andreas Schwab To: Sagar Shrikant Kadam Subject: Re: [PATCH v5 3/3] i2c-ocores: sifive: add polling mode workaround for FU540-C000 SoC. References: <1558361478-4381-1-git-send-email-sagar.kadam@sifive.com> <1558361478-4381-4-git-send-email-sagar.kadam@sifive.com> X-Yow: I can see you GUYS an' GALS need a LOT of HELP...You're all very STUPID!! I used to be STUPID, too..before I started watching UHF-TV!! Date: Tue, 21 May 2019 10:33:48 +0200 In-Reply-To: <1558361478-4381-4-git-send-email-sagar.kadam@sifive.com> (Sagar Shrikant Kadam's message of "Mon, 20 May 2019 19:41:18 +0530") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190521_013353_824320_598087EE X-CRM114-Status: UNSURE ( 9.01 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, andrew@lunn.ch, peter@korsgaard.com, devicetree@vger.kernel.org, palmer@sifive.com, linux-kernel@vger.kernel.org, robh+dt@kernel.org, linux-i2c@vger.kernel.org, paul.walmsley@sifive.com, linux-riscv@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+infradead-linux-riscv=archiver.kernel.org@lists.infradead.org On Mai 20 2019, Sagar Shrikant Kadam wrote: > The i2c-ocore driver already has a polling mode interface.But it needs > a workaround for FU540 Chipset on HiFive unleashed board (RevA00). > There is an erratum in FU540 chip that prevents interrupt driven i2c > transfers from working, and also the I2C controller's interrupt bit > cannot be cleared if set, due to this the existing i2c polling mode > interface added in mainline earlier doesn't work, and CPU stall's > infinitely, when-ever i2c transfer is initiated. > > Ref:previous polling mode support in mainline > > commit 69c8c0c0efa8 ("i2c: ocores: add polling interface") > > The workaround / fix under OCORES_FLAG_BROKEN_IRQ is particularly for > FU540-COOO SoC. After commit dd7dbf0eb090 this no longer fits. Andreas. -- Andreas Schwab, SUSE Labs, schwab@suse.de GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 "And now for something completely different." _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv