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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83E70C433FE for ; Mon, 8 Nov 2021 18:42:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7434D610C8 for ; Mon, 8 Nov 2021 18:42:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235815AbhKHSpK (ORCPT ); Mon, 8 Nov 2021 13:45:10 -0500 Received: from mga18.intel.com ([134.134.136.126]:65329 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235810AbhKHSpI (ORCPT ); Mon, 8 Nov 2021 13:45:08 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10162"; a="219201072" X-IronPort-AV: E=Sophos;i="5.87,218,1631602800"; d="scan'208";a="219201072" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Nov 2021 10:42:20 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,218,1631602800"; d="scan'208";a="503150696" Received: from maru.jf.intel.com ([10.54.51.77]) by orsmga008.jf.intel.com with ESMTP; 08 Nov 2021 10:42:20 -0800 From: jae.hyun.yoo@intel.com To: Rob Herring , Corey Minyard , Joel Stanley , Andrew Jeffery , Cedric Le Goater , Haiyue Wang , ChiaWei Wang , Jae Hyun Yoo Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, openipmi-developer@lists.sourceforge.net Subject: [PATCH v3 6/6] ipmi: kcs_bmc_aspeed: add clock control logic Date: Mon, 8 Nov 2021 11:02:00 -0800 Message-Id: <20211108190200.290957-7-jae.hyun.yoo@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211108190200.290957-1-jae.hyun.yoo@intel.com> References: <20211108190200.290957-1-jae.hyun.yoo@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Jae Hyun Yoo If LPC KCS driver is registered ahead of lpc-ctrl module, LPC KCS block will be enabled without heart beating of LCLK until lpc-ctrl enables the LCLK. This issue causes improper handling on host interrupts when the host sends interrupts in that time frame. Then kernel eventually forcibly disables the interrupt with dumping stack and printing a 'nobody cared this irq' message out. To prevent this issue, all LPC sub drivers should enable LCLK individually so this patch adds clock control logic into the LPC KCS driver. Note: dtsi change in this patch series should be applied along with, and dtbs should be re-compiled after applying this series since it's adding a new required property otherwise this driver will not be probed correctly. Fixes: be2ed207e374 ("ipmi: add an Aspeed KCS IPMI BMC driver") Signed-off-by: Jae Hyun Yoo Reviewed-by: Joel Stanley --- v2 -> v3: * Simplified the -EPROBE_DEFER handling using dev_err_probe(). v1 -> v2: * No change. drivers/char/ipmi/kcs_bmc_aspeed.c | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/drivers/char/ipmi/kcs_bmc_aspeed.c b/drivers/char/ipmi/kcs_bmc_aspeed.c index 92a37b33494c..66c9f51ae611 100644 --- a/drivers/char/ipmi/kcs_bmc_aspeed.c +++ b/drivers/char/ipmi/kcs_bmc_aspeed.c @@ -6,6 +6,7 @@ #define pr_fmt(fmt) "aspeed-kcs-bmc: " fmt #include +#include #include #include #include @@ -126,6 +127,8 @@ struct aspeed_kcs_bmc { bool remove; struct timer_list timer; } obe; + + struct clk *clk; }; struct aspeed_kcs_of_ops { @@ -620,24 +623,34 @@ static int aspeed_kcs_probe(struct platform_device *pdev) return -ENODEV; } + priv->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(priv->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(priv->clk), + "Couldn't get clock\n"); + rc = clk_prepare_enable(priv->clk); + if (rc) { + dev_err(&pdev->dev, "Couldn't enable clock\n"); + return rc; + } + spin_lock_init(&priv->obe.lock); priv->obe.remove = false; timer_setup(&priv->obe.timer, aspeed_kcs_check_obe, 0); rc = aspeed_kcs_set_address(kcs_bmc, addrs, nr_addrs); if (rc) - return rc; + goto err; /* Host to BMC IRQ */ rc = aspeed_kcs_config_downstream_irq(kcs_bmc, pdev); if (rc) - return rc; + goto err; /* BMC to Host IRQ */ if (have_upstream_irq) { rc = aspeed_kcs_config_upstream_irq(priv, upstream_irq[0], upstream_irq[1]); if (rc < 0) - return rc; + goto err; } else { priv->upstream_irq.mode = aspeed_kcs_irq_none; } @@ -650,13 +663,19 @@ static int aspeed_kcs_probe(struct platform_device *pdev) rc = kcs_bmc_add_device(&priv->kcs_bmc); if (rc) { dev_warn(&pdev->dev, "Failed to register channel %d: %d\n", kcs_bmc->channel, rc); - return rc; + goto err; } dev_info(&pdev->dev, "Initialised channel %d at 0x%x\n", kcs_bmc->channel, addrs[0]); return 0; + +err: + aspeed_kcs_enable_channel(kcs_bmc, false); + clk_disable_unprepare(priv->clk); + + return rc; } static int aspeed_kcs_remove(struct platform_device *pdev) @@ -664,6 +683,7 @@ static int aspeed_kcs_remove(struct platform_device *pdev) struct aspeed_kcs_bmc *priv = platform_get_drvdata(pdev); struct kcs_bmc_device *kcs_bmc = &priv->kcs_bmc; + clk_disable_unprepare(priv->clk); kcs_bmc_remove_device(kcs_bmc); aspeed_kcs_enable_channel(kcs_bmc, false); -- 2.25.1