From patchwork Mon Jun 24 09:22:13 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sibi Sankar X-Patchwork-Id: 13709240 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 812E31304B1; Mon, 24 Jun 2024 09:23:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719220990; cv=none; b=Q/PpkjI7J6oUciyffsqeLMiNLFWdikXVfIy6h+s2r1E23+bmcJEhp1S374ouiBaZl+O1WgnoNnZiVP86V+vX12atWtfwKwJGpTRFSTIU9YInJZTQQankTxKEYfyEEhwWXHeSGI4As8l/oa88hY9MRx1BsMLkzX8g2eKBo8a/xDg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719220990; c=relaxed/simple; bh=VSdyIqcXKIeXywG64FX9bSiDwrUvzE9Hv8UawMJCHow=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=iGKfTRXWlqQE+KVuWfsGq5H1+YUm0luS4hkxBFhSlTo9BbrLRF+XoT2Uq4jh/VdU+jmad9yOP/S8avVkZ/0eI7KTh8UGLda273gItm2jrCABb41TZ3wqioXexwEkY7eD7EDQuYaC1AHwfLnckhdwu2YvBIiEdRqpAK1yb3mXXrw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com; spf=pass smtp.mailfrom=quicinc.com; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b=fB1TAbm2; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=quicinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b="fB1TAbm2" Received: from pps.filterd (m0279864.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 45O8Yw49023757; Mon, 24 Jun 2024 09:23:05 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= 5IyIy2raQyI/j8Y4tp3EjbrHtT/L8h4cYoQYDRAXN/I=; b=fB1TAbm2zsfQ3n1q 2GO+TCbkjGNeiukzbxHg/lPneBf5tyiuYbrxr03CapOLtZf/gK1msEqjg6KfNyT5 9rY2RiXCj2ms25oe+AQonqGfiL2bzVLaFp+YHlGExHkYgcr+tpVUfYwrtCBQVfGw Pwt/3UPF3ots51EXpXacKwul1zLWObHdLWm7qiNPwxMXJ18a7mkEKsDH2ZAEnqNY EdlzWJqItSyyF9w69lzwLhoBgFjL9J6GztZA1bWaC+fTVGnZipk77HQ404Gtvdon r/dcL4lYti0C8basiJCcRH4+nFDx7SNIpTnYdlcq0UEHsVJMtOMZqGT/SXyKcA+W rQCG+A== Received: from nalasppmta04.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3ywqshk56q-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 24 Jun 2024 09:23:05 +0000 (GMT) Received: from nalasex01a.na.qualcomm.com (nalasex01a.na.qualcomm.com [10.47.209.196]) by NALASPPMTA04.qualcomm.com (8.17.1.19/8.17.1.19) with ESMTPS id 45O9N42I023535 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 24 Jun 2024 09:23:04 GMT Received: from hu-sibis-blr.qualcomm.com (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.9; Mon, 24 Jun 2024 02:22:59 -0700 From: Sibi Sankar To: , , , , , , CC: , , , , , , , , Subject: [PATCH V3 3/4] soc: qcom: icc-bwmon: Allow for interrupts to be shared across instances Date: Mon, 24 Jun 2024 14:52:13 +0530 Message-ID: <20240624092214.146935-4-quic_sibis@quicinc.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240624092214.146935-1-quic_sibis@quicinc.com> References: <20240624092214.146935-1-quic_sibis@quicinc.com> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01a.na.qualcomm.com (10.47.209.196) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: LjVomsMhcbDicQrk_2pM4_klvla9gWVm X-Proofpoint-GUID: LjVomsMhcbDicQrk_2pM4_klvla9gWVm X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.28.16 definitions=2024-06-24_08,2024-06-21_01,2024-05-17_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 clxscore=1015 bulkscore=0 phishscore=0 suspectscore=0 lowpriorityscore=0 malwarescore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 priorityscore=1501 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2406140001 definitions=main-2406240075 The multiple BWMONv4 instances available on the X1E80100 SoC use the same interrupt number. Mark them are shared to allow for re-use across instances. Using IRQF_SHARED coupled with devm_request_threaded_irq implies that the irq can still trigger during/after bwmon_remove due to other active bwmon instances. Handle this race by relying on bwmon_disable to disable the interrupt and coupled with explicit request/free irqs. Signed-off-by: Sibi Sankar Reviewed-by: Dmitry Baryshkov --- v3: * Update commit message describing the race condition. [Bjorn] * Update comment in the bwmon driver. [Dmitry] drivers/soc/qcom/icc-bwmon.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/soc/qcom/icc-bwmon.c b/drivers/soc/qcom/icc-bwmon.c index ecddb60bd665..e7851974084b 100644 --- a/drivers/soc/qcom/icc-bwmon.c +++ b/drivers/soc/qcom/icc-bwmon.c @@ -783,9 +783,14 @@ static int bwmon_probe(struct platform_device *pdev) bwmon->dev = dev; bwmon_disable(bwmon); - ret = devm_request_threaded_irq(dev, bwmon->irq, bwmon_intr, - bwmon_intr_thread, - IRQF_ONESHOT, dev_name(dev), bwmon); + + /* + * SoCs with multiple cpu-bwmon instances can end up using a shared interrupt + * line. Using the devm_ variant might result in the IRQ handler being executed + * after bwmon_disable in bwmon_remove() + */ + ret = request_threaded_irq(bwmon->irq, bwmon_intr, bwmon_intr_thread, + IRQF_ONESHOT | IRQF_SHARED, dev_name(dev), bwmon); if (ret) return dev_err_probe(dev, ret, "failed to request IRQ\n"); @@ -800,6 +805,7 @@ static void bwmon_remove(struct platform_device *pdev) struct icc_bwmon *bwmon = platform_get_drvdata(pdev); bwmon_disable(bwmon); + free_irq(bwmon->irq, bwmon); } static const struct icc_bwmon_data msm8998_bwmon_data = {