From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 8F3E621B19E for ; Mon, 9 Jun 2025 16:01:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749484886; cv=none; b=iKWOFJuC4dOIAXsUk9sQwGNKKA2GB8H8TB/yvK3Ue6HNY6cucyizw31LXXPb8pCkLofmpwfLo/u7GYzRoS0nl6LRHLfH/yrJam+DUsfHhNYkYbdtmycABEKzxHJaKi2wHxMwrhheHAgs7lljupjAr3WeI9H9tv/1bVVArJpCIGE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749484886; c=relaxed/simple; bh=yVcviqXGLX8XXxiv2l48G8MI9BCvDehEgF2Iupn+Bew=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=bVg6SY+je0evxJ2n12246EMUE+faq01lHdeU1esGEPs/TZvNs2egy6c3wHWd77jAnjx+JDayhEamOEOPU3HBfaZ9YVSLzoAIiqph33QY1pWq5gMd1L+dpJ6h0tcJ1aptxtcxd0IvlJ3t2NRNeghtHLOZcQ21O2b87YsRejZP3js= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6F9D31515; Mon, 9 Jun 2025 09:01:06 -0700 (PDT) Received: from e132581.arm.com (e132581.arm.com [10.1.196.87]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0549C3F673; Mon, 9 Jun 2025 09:01:23 -0700 (PDT) From: Leo Yan Date: Mon, 09 Jun 2025 17:00:40 +0100 Subject: [PATCH v3 6/9] coresight: Avoid enable programming clock duplicately Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20250609-arm_cs_fix_clock_v3_public-v3-6-423b3f1f241d@arm.com> References: <20250609-arm_cs_fix_clock_v3_public-v3-0-423b3f1f241d@arm.com> In-Reply-To: <20250609-arm_cs_fix_clock_v3_public-v3-0-423b3f1f241d@arm.com> To: Suzuki K Poulose , Mike Leach , James Clark , Anshuman Khandual , Alexander Shishkin , Greg Kroah-Hartman Cc: coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Leo Yan X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1749484873; l=1497; i=leo.yan@arm.com; s=20250604; h=from:subject:message-id; bh=yVcviqXGLX8XXxiv2l48G8MI9BCvDehEgF2Iupn+Bew=; b=7Mj8BicH2mQES5cPM2ECdFxjX0lrMREtg/dUsRZya//fEOsKpYpcuN7O6bIzUWiJMlGOJrlDq iGSJgtqOVSGBHU+lCN58Zk0WRydUQVIUczQ0nLZS4B02IrrjWMYZRlh X-Developer-Key: i=leo.yan@arm.com; a=ed25519; pk=k4BaDbvkCXzBFA7Nw184KHGP5thju8lKqJYIrOWxDhI= The programming clock is enabled by AMBA bus driver before a dynamic probe. As a result, a CoreSight driver may redundantly enable the same clock. To avoid this, add a check for device type and skip enabling the programming clock for AMBA devices. The returned NULL pointer will be tolerated by the drivers. Fixes: 73d779a03a76 ("coresight: etm4x: Change etm4_platform_driver driver for MMIO devices") Signed-off-by: Leo Yan --- include/linux/coresight.h | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/include/linux/coresight.h b/include/linux/coresight.h index dd2b4cc7a2b70cf060a3207548fe80e3824c489f..9afa1f76c78a3347e54d94fe9a9ebed72e3fff8e 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -480,15 +480,18 @@ static inline bool is_coresight_device(void __iomem *base) * Returns: * * clk - Clock is found and enabled + * NULL - Clock is not needed as it is managed by the AMBA bus driver * ERROR - Clock is found but failed to enable */ static inline struct clk *coresight_get_enable_apb_pclk(struct device *dev) { - struct clk *pclk; + struct clk *pclk = NULL; - pclk = devm_clk_get_enabled(dev, "apb_pclk"); - if (IS_ERR(pclk)) - pclk = devm_clk_get_enabled(dev, "apb"); + if (!dev_is_amba(dev)) { + pclk = devm_clk_get_enabled(dev, "apb_pclk"); + if (IS_ERR(pclk)) + pclk = devm_clk_get_enabled(dev, "apb"); + } return pclk; } -- 2.34.1