From nobody Wed Oct 8 15:13:37 2025 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4BB4F2D9EC1 for ; Fri, 27 Jun 2025 11:52:30 +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=1751025151; cv=none; b=auEaYFe+KRyqtjK2iTCfp3pXzK17Bfsu7c8ceh+RjrqgZ7EBDMzOdG/J8hufvGd1jH4tLhapfT1F9UGnjmF5pvS4gteN2RzVu48UXnP5qeAdhxhf5inqMCGzHu5dY7WWXUTSss9TpP6Y714Kko4E7X92+FwOz+5Vc1VlOJd7nMU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751025151; c=relaxed/simple; bh=cuazPSya7V6vGGtK1ePheZ6n35wrfk3eIkvkqRNyloA=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=mAR69Dywr+QydivknKQIPxezE6orfCKtaClON0CHNEb5COpg1WIvpAE6/18T22Es5z/jEq7WSzclV/46PMDf5+rj2vZPhxPIv2hL0Lrj5aNPJ6Zyw90odL4WLE2JA7RFTD0s2v65667K61GKSXUeX2JC6zeduubwNi66nxCdwzI= 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 60C921A00; Fri, 27 Jun 2025 04:52:12 -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 1D7B13F58B; Fri, 27 Jun 2025 04:52:27 -0700 (PDT) From: Leo Yan Date: Fri, 27 Jun 2025 12:51:52 +0100 Subject: [PATCH v4 06/10] 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: quoted-printable Message-Id: <20250627-arm_cs_fix_clock_v4-v4-6-0ce0009c38f8@arm.com> References: <20250627-arm_cs_fix_clock_v4-v4-0-0ce0009c38f8@arm.com> In-Reply-To: <20250627-arm_cs_fix_clock_v4-v4-0-0ce0009c38f8@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=1751025136; l=1557; i=leo.yan@arm.com; s=20250604; h=from:subject:message-id; bh=cuazPSya7V6vGGtK1ePheZ6n35wrfk3eIkvkqRNyloA=; b=VCkFsX6m41Kv+mHJlteDC2dQpF4mV74yWGfghjzC7StyXEkSS56z1DpTX5/ag0AklGtAuTOmI +X7XVN1Z6UHCNhT/SIfT5JLEcXAe7UFXMo9UMVcVGQSvI+lsIRTmWrd 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") Reviewed-by: Anshuman Khandual 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..9afa1f76c78a3347e54d94fe9a9= ebed72e3fff8e 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 =3D NULL; =20 - pclk =3D devm_clk_get_enabled(dev, "apb_pclk"); - if (IS_ERR(pclk)) - pclk =3D devm_clk_get_enabled(dev, "apb"); + if (!dev_is_amba(dev)) { + pclk =3D devm_clk_get_enabled(dev, "apb_pclk"); + if (IS_ERR(pclk)) + pclk =3D devm_clk_get_enabled(dev, "apb"); + } =20 return pclk; } --=20 2.34.1