From patchwork Thu Jul 20 08:33:04 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Devi Priya X-Patchwork-Id: 13320135 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 29EDAEB64DD for ; Thu, 20 Jul 2023 08:57:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230008AbjGTI5A (ORCPT ); Thu, 20 Jul 2023 04:57:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35862 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231878AbjGTId0 (ORCPT ); Thu, 20 Jul 2023 04:33:26 -0400 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6DD11268C; Thu, 20 Jul 2023 01:33:25 -0700 (PDT) Received: from pps.filterd (m0279862.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 36K5SqqW022420; Thu, 20 Jul 2023 08:33:21 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : mime-version : content-type; s=qcppdkim1; bh=MP1Bkyz5bjTyT8+WFtnsD0N1nt1uVmVkvyHsWOopleU=; b=lVYXiOyhqoks00qR0ZRhE9p2fL+ZqQgRfwPw6HrRDe0kHeU+tiQUMxAoCPgR3JL/EwKS u2fu/tYfYknaskP1+q8w7Jtotc2/cqO1JTdDwdMWxL888aoV0rb0itmWZf1hgiHDk4vV z2660tVT5Qd82Ods51nqUhOLrPFhdzuLfBz6h1F6tVuQysrd4de7s5pjq7dpYkX5gufS YMAdPkCjM0oHYEuq0qufHpxbwxI+MP7Z/dIdRj4F7zqIk4CMHjmLTINzF7Hv4kYXLyWZ 19I+yvVe4VILLIPF8+bb93ZlsH/BEj72rsZ4UOsZe/9iXOdlrZIcmAiA/N55uVipe3gW 4g== Received: from nalasppmta02.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3rx728u853-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 20 Jul 2023 08:33:21 +0000 Received: from nalasex01a.na.qualcomm.com (nalasex01a.na.qualcomm.com [10.47.209.196]) by NALASPPMTA02.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 36K8XKi7022628 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 20 Jul 2023 08:33:20 GMT Received: from devipriy-linux.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 15.2.1118.30; Thu, 20 Jul 2023 01:33:17 -0700 From: Devi Priya To: , , , , , , , CC: Subject: [PATCH] clk: qcom: clk-rcg2: Fix wrong RCG clock rate for high parent frequencies Date: Thu, 20 Jul 2023 14:03:04 +0530 Message-ID: <20230720083304.28881-1-quic_devipriy@quicinc.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] 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-GUID: IdJx1srWEX_zfV2aQWymGAF7fjq-A4I6 X-Proofpoint-ORIG-GUID: IdJx1srWEX_zfV2aQWymGAF7fjq-A4I6 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.591,FMLib:17.11.176.26 definitions=2023-07-20_02,2023-07-19_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 phishscore=0 bulkscore=0 suspectscore=0 priorityscore=1501 lowpriorityscore=0 mlxlogscore=876 impostorscore=0 spamscore=0 clxscore=1015 adultscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2306200000 definitions=main-2307200070 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org If the parent clock rate is greater than unsigned long max/2 then integer overflow happens when calculating the clock rate on 32-bit systems. As RCG2 uses half integer dividers, the clock rate is first being multiplied by 2 which will overflow the unsigned long max value. So, use unsigned long long for rate computations to avoid overflow. Signed-off-by: Devi Priya Reviewed-by: Konrad Dybcio --- drivers/clk/qcom/clk-rcg2.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/clk/qcom/clk-rcg2.c b/drivers/clk/qcom/clk-rcg2.c index e22baf3a7112..42d00b134975 100644 --- a/drivers/clk/qcom/clk-rcg2.c +++ b/drivers/clk/qcom/clk-rcg2.c @@ -156,18 +156,18 @@ static int clk_rcg2_set_parent(struct clk_hw *hw, u8 index) * hid_div n */ static unsigned long -calc_rate(unsigned long rate, u32 m, u32 n, u32 mode, u32 hid_div) +calc_rate(unsigned long parent_rate, u32 m, u32 n, u32 mode, u32 hid_div) { + u64 rate = parent_rate; + if (hid_div) { rate *= 2; - rate /= hid_div + 1; + do_div(rate, hid_div + 1); } if (mode) { - u64 tmp = rate; - tmp *= m; - do_div(tmp, n); - rate = tmp; + rate *= m; + do_div(rate, n); } return rate;