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=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 5415EC54E49 for ; Thu, 7 May 2020 14:29:43 +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 28E962083B for ; Thu, 7 May 2020 14:29:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Bzj9XZMw"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="VszrsqY7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 28E962083B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=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:References:In-Reply-To: Message-Id:Date: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=RgQduQo6i3fMjuvbgj2y07M0FICFP9MiWBJkh1rBhJU=; b=Bzj9XZMw0s1r5/ ALhHCt8p05lxt8erMnuogZfwQkYnjDVC2QhNbfoZ6jid7Oc6cJ2npA4uTxJa3Cz8GksTkfChFOxwO EJsiROLmNnQhvDqcghSPwfzeqwjIz8dzSRc1zYVel2xxX5sgqohw5qjmstJ4bZXZqd9GevxIcPQ0e aDx18e3b42EJNO5hTJN0cbm+LUWH/KWMOTK8T46paHoSYJuc2vPMxiiv+dAgVMvwonkPfLbb9j+HF HkSnv4LYSUm6PpLdrhYJeaey5gvckoduscnkjPQ2Bg1bIM8yzDPQXNL8tu/gc2MpnGB76NNyLGdlH 3VQsWflx3mImjuCACExw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jWhWw-000387-BG; Thu, 07 May 2020 14:29:42 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jWhWS-0002hm-4q for linux-arm-kernel@lists.infradead.org; Thu, 07 May 2020 14:29:14 +0000 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7929E20A8B; Thu, 7 May 2020 14:29:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588861751; bh=mKuQExT/XtGq4HcwCYsGAbbI38P9Ix+FvVyT7xS0ZcU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VszrsqY7GJ0p9HcCzdvI5xI/OIMdMMv6/HWpq/JKxdP9cwBWaSXP8LBlFBtYm9CkK O7CQnzna3jH5GaIwCke8Tx2dMLNKe7Z9swKeRUM3Z17r/dt82LK4mwacU++RODkF2I MuzMwrH9Nw7S1au6+dr466gzX9LVYjgG77puT5cY= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 32/35] i2c: aspeed: Avoid i2c interrupt status clear race condition. Date: Thu, 7 May 2020 10:28:26 -0400 Message-Id: <20200507142830.26239-32-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200507142830.26239-1-sashal@kernel.org> References: <20200507142830.26239-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200507_072912_235639_45D2C813 X-CRM114-Status: GOOD ( 10.76 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sasha Levin , ryan_chen , linux-aspeed@lists.ozlabs.org, Wolfram Sang , Benjamin Herrenschmidt , openbmc@lists.ozlabs.org, linux-i2c@vger.kernel.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: ryan_chen [ Upstream commit c926c87b8e36dcc0ea5c2a0a0227ed4f32d0516a ] In AST2600 there have a slow peripheral bus between CPU and i2c controller. Therefore GIC i2c interrupt status clear have delay timing, when CPU issue write clear i2c controller interrupt status. To avoid this issue, the driver need have read after write clear at i2c ISR. Fixes: f327c686d3ba ("i2c: aspeed: added driver for Aspeed I2C") Signed-off-by: ryan_chen Acked-by: Benjamin Herrenschmidt [wsa: added Fixes tag] Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-aspeed.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c index 7b098ff5f5dd3..dad6e432de89f 100644 --- a/drivers/i2c/busses/i2c-aspeed.c +++ b/drivers/i2c/busses/i2c-aspeed.c @@ -603,6 +603,7 @@ static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id) /* Ack all interrupts except for Rx done */ writel(irq_received & ~ASPEED_I2CD_INTR_RX_DONE, bus->base + ASPEED_I2C_INTR_STS_REG); + readl(bus->base + ASPEED_I2C_INTR_STS_REG); irq_remaining = irq_received; #if IS_ENABLED(CONFIG_I2C_SLAVE) @@ -645,9 +646,11 @@ static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id) irq_received, irq_handled); /* Ack Rx done */ - if (irq_received & ASPEED_I2CD_INTR_RX_DONE) + if (irq_received & ASPEED_I2CD_INTR_RX_DONE) { writel(ASPEED_I2CD_INTR_RX_DONE, bus->base + ASPEED_I2C_INTR_STS_REG); + readl(bus->base + ASPEED_I2C_INTR_STS_REG); + } spin_unlock(&bus->lock); return irq_remaining ? IRQ_NONE : IRQ_HANDLED; } -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel