From mboxrd@z Thu Jan 1 00:00:00 1970 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 E6ED03074AC for ; Fri, 28 Nov 2025 14:30:01 +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=1764340204; cv=none; b=Al3uKe2Hvh8YZYh3LbHF05d0XwUcfJrxdHAXc/danPDTygn+iTcglunkGhS3CJ2LE0p+Vmh1PJWX8TainyIIPfLPyaf50xgCEVPSKU5i4ttRHt9HZtHbyftnZ8GozYpb/tiZv5KC2FKF0W0j6qct8NNpaotrQsFan8AeqRa+G4g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764340204; c=relaxed/simple; bh=tRNBe4fjRO1hx9IAslahBhVvZMSRTvihSK2tbffhBp0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Ns6TZfGy/XwnmJEHh9FfYEb5obYqyEYEXE0+jkLrMl7njFli5SoNON1ttJYqQ0+0VgdtghcfNYpgIRcsIKdkC/v8EdZKpP3o6hHGF+BPiCoN+D+MTFnUNgep7pLVfH4wEAvzplzNs69euMfP0kP2pgbA6DWxkttpd/a4T2fxh78= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com; spf=pass smtp.mailfrom=oss.qualcomm.com; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b=iG8Ozd1t; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b=a+Ou6BND; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b="iG8Ozd1t"; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b="a+Ou6BND" Received: from pps.filterd (m0279864.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 5AS8P8UW2986540 for ; Fri, 28 Nov 2025 14:30:00 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qualcomm.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= I8m/Cd13luBRYG7SBIJit3CvmjCN2CxIcV7mIbzooIg=; b=iG8Ozd1tc2RsfYFs sSv5uIi6bkvfKUUvQYZ1efBDhdy/Nsbf6VL/TCtjnHct7tR1j+5J/fZluNL/wERy OCV+HreSeU4pB/zn2RgitxSg+nh7g3zdr53Smk5QLk6hQqFc10eEoxu0G/vjtUu3 AKglRC/z5aFpId35ztl8iNZOsxTXYNw3QdmPkigDyoYijxTA5mctG6Z5majWcX62 436bPIlgqeFEexVB/FyqAfcnY/VXv/lAb0iQHzLB4Z3FWbM0+3mDzmAxpkWVdyrt GLrEkWc0h8sElqYW3O1gddf37pSuOrpeOpHW3f14YJJcgDYHaS1E8nQ23IUgIetm tDETWQ== Received: from mail-pg1-f200.google.com (mail-pg1-f200.google.com [209.85.215.200]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 4apmvxkke1-1 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NOT) for ; Fri, 28 Nov 2025 14:30:00 +0000 (GMT) Received: by mail-pg1-f200.google.com with SMTP id 41be03b00d2f7-b62da7602a0so2021448a12.2 for ; Fri, 28 Nov 2025 06:30:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oss.qualcomm.com; s=google; t=1764340200; x=1764945000; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=I8m/Cd13luBRYG7SBIJit3CvmjCN2CxIcV7mIbzooIg=; b=a+Ou6BNDQRak3prVWQh81bkpVgDNzdYyb+5ZyD6aOjZLwfOl0ExP6GZZwWUzFZgDzE e0UtmDw+r4oqr/LYxYrXO95EGKbiT7D20QGX9vcA2BGAmvdvcYudgb43W5gvVc1RhEyP l7TbSOsytajJ5oczGPpUplZd7VpdzyIivPGGxWJNgLYpFFui4+TKHuEMbCknVO7XMu1H pOpbqgH3vy93cCpiycb0F0TozETIyAz9Ko+vbUBnLfvTRiplJ4H4mdo34xnb4B1l8VbN 8EDdRR0PNXhYbJDjVCEbWJ4AMqjCDiHZxEn5qxjdXSmjQiVvwrN54GuaP57SYImAkAo2 Mb1Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1764340200; x=1764945000; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=I8m/Cd13luBRYG7SBIJit3CvmjCN2CxIcV7mIbzooIg=; b=KuaRTjENLoSppcK7WFUhxRKzbiT6Dqnjef3KtBMjdWS+T3tgShhoIVM3JzmsVo2sZ6 UX2DbCtbxxwlXXbFjObkc/o9qqfRwxKsXy4csbdj3rEy8HEApyjhdKf6D9jded0qrft/ e0LSgwPT+PvguxmSNXABwklbyVERTZIcz9Sc1KSF8OOxn8dBV2uW/SFDvu6wXmCtUpQ0 6R9Z04h7BUCetoDj0xr8pSUGuYMmFZ6Rr8ZdiZki+hyI4QVDQJfVGcOVmqq4TDfFovGO a0R2n5QfzK3lobzdFgjOEWmMwMZe+BmqBiwUGrzcpYshpmwG/g+rHx1d3tUt4lyD45XN dAAQ== X-Forwarded-Encrypted: i=1; AJvYcCV1sl6FkKv6rqgKkf0YCtFMRmcO/bzsoeQPFLmkESjEXACszmitIq1Ir5YpaiwtnMh1ApKT3Ym1IPhWWYw=@vger.kernel.org X-Gm-Message-State: AOJu0YzPJUF8RAzIeBvfjxhUBreZWANeRMzRy2ZTh/hDnWiXd2ez8MLE ohjfQLfLF1IMKgJRZ8PfaZL+oldNwFZSrrgPNSXfNVO3Do2JJk3jCvQARJvsV5qT+O+FGXcuH+e bcuMGDSpZvghc58dLNSQCBIERn/bpPS1eBeQdQveLWOiuTz9tIkwS8CfoZHVuMbVGg1c= X-Gm-Gg: ASbGnctjo2n72yE+rUCRZ8hdGuaTi4fFP/ua41vCBBLPnq8JlBqZH6dX3sXEstgm9sb uDv0F5l+sqjuw1TQzDhRFdr2VYyq0t0cmUwYGP/4AHs4Gc46Qrc7dWDbYxVAL2O406/o/25/mR5 MMRpC6O82FbA8EsAwQ8eobnaTtNhKx7mlWIGUQAYAbjzY1hKCcafEaEWD9J5nkIPdxANdupNCUc 6zCzYoDZIliJsoFIoQnZZZp7RvI5NAIZB4oNhydztOTQuqVU+8YuPDhR9PsTnkLJ6hRCRrMPf2d tbp9zwRRxNNiqRcpEgZTm5I1jAL9le5/XFe/Fy8+jzM6pRAXXUDB+uFRMqBBSfF8G2/B00RfTMZ sFdphhYM116JSeYco2+Dokxs0Ogzu0RH9NA== X-Received: by 2002:a17:903:234a:b0:299:fc47:d7e3 with SMTP id d9443c01a7336-29b6c57224emr319638295ad.31.1764340199718; Fri, 28 Nov 2025 06:29:59 -0800 (PST) X-Google-Smtp-Source: AGHT+IGQDWkrRLq6Z/YilM0CQ3+TKY3UGACkoNWNyTlguCOA8KyIumCSBYe74T3rnKhV4ld7zREH+Q== X-Received: by 2002:a17:903:234a:b0:299:fc47:d7e3 with SMTP id d9443c01a7336-29b6c57224emr319637915ad.31.1764340199231; Fri, 28 Nov 2025 06:29:59 -0800 (PST) Received: from [192.168.1.119] ([183.192.29.70]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-29bceb54c6asm48719675ad.90.2025.11.28.06.29.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 28 Nov 2025 06:29:58 -0800 (PST) Message-ID: Date: Fri, 28 Nov 2025 22:29:32 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/5] clk: qcom: cmnpll: Account for reference clock divider To: Konrad Dybcio , Bjorn Andersson , Michael Turquette , Stephen Boyd , Luo Jie , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Konrad Dybcio Cc: linux-arm-msm@vger.kernel.org, linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, quic_kkumarcs@quicinc.com, quic_linchen@quicinc.com, quic_leiwei@quicinc.com, quic_pavir@quicinc.com, quic_suruchia@quicinc.com References: <20251128-qcom_ipq5332_cmnpll-v1-0-55127ba85613@oss.qualcomm.com> <20251128-qcom_ipq5332_cmnpll-v1-1-55127ba85613@oss.qualcomm.com> <2d83f0d3-4798-4183-9e3d-9972db706cdb@oss.qualcomm.com> Content-Language: en-US From: Jie Luo In-Reply-To: <2d83f0d3-4798-4183-9e3d-9972db706cdb@oss.qualcomm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Authority-Analysis: v=2.4 cv=Vtguwu2n c=1 sm=1 tr=0 ts=6929b1e8 cx=c_pps a=oF/VQ+ItUULfLr/lQ2/icg==:117 a=sdhyOahhduPysBwc4dimug==:17 a=IkcTkHD0fZMA:10 a=6UeiqGixMTsA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=HfvJj5BQp2OzgikQKL0A:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=3WC7DwWrALyhR5TkjVHa:22 X-Proofpoint-GUID: a7CNUYQUzQqPeG8-zXsIOiqjObtwvo0H X-Proofpoint-ORIG-GUID: a7CNUYQUzQqPeG8-zXsIOiqjObtwvo0H X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMTI4MDEwNiBTYWx0ZWRfX+9BuASCw5mwy h5Zy05OW52iMm9dhuUDkqsoqXm++o4LtMhMpkyZ4K6WNQFIwuaP2JgTPyrCoipocAjH8n+4KX1g seUQvvZ9BbUhvujCAKTURnVx0CJzzvH2j+HRkj8WWZUfYpUta5LPl9aV9WHzqKhtSqwcry3gtKW bjDFkSrEFSndZqw1dQTpysFhzb63qbNFceRR+aX7NTpFFrKXepYDQEwvDBIW+RgGtzbXxsU5ORx eMausNPKaQreakTZji9JdRn/b4ZLtlBE6N9eg/X25qyjpobLxj+C7TnlhPCg3IC/45kG/gRLrWA o11VQhNizG9ObcswAHl+32zZy6/Q/jgc2lNwcXI3dHXyTdk2ErAZt8iuPMBcWfBBFfAvZyRPCX1 dKwwE4h+jrscdE5ljY3igA9zGGAGmQ== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2025-11-28_03,2025-11-27_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 priorityscore=1501 impostorscore=0 phishscore=0 adultscore=0 lowpriorityscore=0 bulkscore=0 clxscore=1015 spamscore=0 suspectscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2510240001 definitions=main-2511280106 On 11/28/2025 7:38 PM, Konrad Dybcio wrote: > On 11/28/25 9:40 AM, Luo Jie wrote: >> The clk_cmn_pll_recalc_rate() function must account for the reference clock >> divider programmed in CMN_PLL_REFCLK_CONFIG. Without this fix, platforms >> with a reference divider other than 1 calculate incorrect CMN PLL rates. >> For example, on IPQ5332 where the reference divider is 2, the computed rate >> becomes twice the actual output. >> >> Read CMN_PLL_REFCLK_DIV and divide the parent rate by this value before >> applying the 2 * FACTOR scaling. This yields the correct rate calculation: >> rate = (parent_rate / ref_div) * 2 * factor. >> >> Maintain backward compatibility with earlier platforms (e.g. IPQ9574, >> IPQ5424, IPQ5018) that use ref_div = 1. > > I'm not sure how to interpret this. Is the value fixed on these platforms > you mentioned, and always shows up as 0? > > Konrad On these platforms the hardware ref_div register comes up with a value of 1 by default. It is, however, still a programmable field and not strictly fixed to 1. The ref_div == 0 check in this patch is only meant as a safety net to avoid a divide‑by‑zero in the rate calculation.