From patchwork Sun Feb 27 17:55:35 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Taniya Das X-Patchwork-Id: 12762062 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 1D362C433F5 for ; Sun, 27 Feb 2022 17:55:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230045AbiB0R40 (ORCPT ); Sun, 27 Feb 2022 12:56:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230012AbiB0R40 (ORCPT ); Sun, 27 Feb 2022 12:56:26 -0500 Received: from so254-9.mailgun.net (so254-9.mailgun.net [198.61.254.9]) by lindbergh.monkeyblade.net (Postfix) with UTF8SMTPS id E76DC4BFEB for ; Sun, 27 Feb 2022 09:55:48 -0800 (PST) DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1645984548; h=Message-Id: Date: Subject: Cc: To: From: Sender; bh=gkmEjTo7bEyVIL1ziLsQ9rJ6k22A10FoGJSEH0UOV3Y=; b=ke8PKlQ1K1X5JuudXL48eSz9d33ZGUHyhKFK04o3bHHuq8e/GZhBqdFVHOEmCrqZsNTRK3Du Gd3dCZWdaYVbGmGyZDGLzeEThQOUVmedU/x1CfZkq6cNq2jaq38jtzI2tEO/aSwnVTTrm6WE T/rGQt2egFJA+5l2UpaVsEk9atQ= X-Mailgun-Sending-Ip: 198.61.254.9 X-Mailgun-Sid: WyI4MzlhZiIsICJsaW51eC1jbGtAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n01.prod.us-west-2.postgun.com with SMTP id 621bbb2333c4b4b759947a25 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Sun, 27 Feb 2022 17:55:47 GMT Sender: tdas=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 4F3A9C4360D; Sun, 27 Feb 2022 17:55:47 +0000 (UTC) Received: from hu-tdas-hyd.qualcomm.com (unknown [202.46.22.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: tdas) by smtp.codeaurora.org (Postfix) with ESMTPSA id 0785EC4338F; Sun, 27 Feb 2022 17:55:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 smtp.codeaurora.org 0785EC4338F Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=codeaurora.org From: Taniya Das To: Stephen Boyd , =?utf-8?q?Michael_Turquette_=C2=A0?= Cc: Rajendra Nayak , linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, Taniya Das Subject: [v3 1/2] clk: qcom: clk-rcg2: Update logic to calculate D value for RCG Date: Sun, 27 Feb 2022 23:25:35 +0530 Message-Id: <20220227175536.3131-1-tdas@codeaurora.org> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org The display pixel clock has a requirement on certain newer platforms to support M/N as (2/3) and the final D value calculated results in underflow errors. As the current implementation does not check for D value is within the accepted range for a given M & N value. Update the logic to calculate the final D value based on the range. Fixes: 99cbd064b059f ("clk: qcom: Support display RCG clocks") Signed-off-by: Taniya Das --- [v3] * Use clamp_t() instead of clamp(). * Update the commit message for the display use case. drivers/clk/qcom/clk-rcg2.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) -- Qualcomm INDIA, on behalf of Qualcomm Innovation Center, Inc.is a member of the Code Aurora Forum, hosted by the Linux Foundation. diff --git a/drivers/clk/qcom/clk-rcg2.c b/drivers/clk/qcom/clk-rcg2.c index e1b1b426fae4..b831975a9606 100644 --- a/drivers/clk/qcom/clk-rcg2.c +++ b/drivers/clk/qcom/clk-rcg2.c @@ -264,7 +264,7 @@ static int clk_rcg2_determine_floor_rate(struct clk_hw *hw, static int __clk_rcg2_configure(struct clk_rcg2 *rcg, const struct freq_tbl *f) { - u32 cfg, mask; + u32 cfg, mask, d_val, not2d_val, n_minus_m; struct clk_hw *hw = &rcg->clkr.hw; int ret, index = qcom_find_src_index(hw, rcg->parent_map, f->src); @@ -283,8 +283,17 @@ static int __clk_rcg2_configure(struct clk_rcg2 *rcg, const struct freq_tbl *f) if (ret) return ret; + /* Calculate 2d value */ + d_val = f->n; + + n_minus_m = f->n - f->m; + n_minus_m *= 2; + + d_val = clamp_t(u32, d_val, f->m, n_minus_m); + not2d_val = ~d_val & mask; + ret = regmap_update_bits(rcg->clkr.regmap, - RCG_D_OFFSET(rcg), mask, ~f->n); + RCG_D_OFFSET(rcg), mask, not2d_val); if (ret) return ret; }