From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 BEF3336A030 for ; Fri, 15 May 2026 01:27:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778808431; cv=none; b=pe87rfI87r3luRKOWbAjjYDtmBgTH8JUkVfnN9dkyPqOX+23UAR+OgpdNogjVUWCZCAoIDjr/wmMT2z+T/NHtu4Ax01uEs5wf1uo7OZLHxNHn/JoTw6HzDKENijroiknHrOPkTucsV5pAiaqdS9r9+mWDRYPjbbJihpI48KpEwE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778808431; c=relaxed/simple; bh=jds/KUEnMypQxF/dsmHVwU7tav2q16u3klT9lSJO4Dw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Okmoi3DovR9CItHwpwOCWu3YvTDJtzoPd4LmU8PZbMGBJ+tmJIwUPeFMay4Mc1H+grVgAA07NSORKWdeykm/lk3YMDys7NLiHfbinLW42VNvr4dZ1NClvkAHq1EIql4GgaessR4SqyS8K3rl/Aw49xnAv9K4IGSQMJJcrXe9bkY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TKn5CzOw; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TKn5CzOw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B9D4C2BCB3; Fri, 15 May 2026 01:27:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778808431; bh=jds/KUEnMypQxF/dsmHVwU7tav2q16u3klT9lSJO4Dw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TKn5CzOw33zLhbULxmodZj4uSBxZUoymOm3B0RWi06fo/Tj2RARVGhm2M6dBAApiH hZdpobN+XsohyfcO+zcpdWbhWFuz+9THuBp/UQBrRu5mAHgEFO/nDgHtth+FviXQem /K4dEkKuze88YD2gaGUbeg7IO9LX6wXwlPwCBdpv1unf/Vvd3zNC9AwuirSn1ocquu LPtaOWT8gpJtSbqvCL/0WpfaECf1gYilANfyrwqjI1psxqkVZxVBgU0Xr/WW5ke+JY OFrjwxtt27geZM/MJWdFqpITcKcRyFl7HDV6OxZY+YyfPMsF26p1GhijOUUowI4pYB AURsy24vtCkRw== Date: Fri, 15 May 2026 10:27:09 +0900 From: Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= To: lirongqing Cc: Ryder Lee , Jianjun Wang , Lorenzo Pieralisi , Manivannan Sadhasivam , Rob Herring , Bjorn Helgaas , Matthias Brugger , AngeloGioacchino Del Regno , linux-pci@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] PCI: mediatek: Fix operator precedence in PCIE_FTS_NUM_L0 macro Message-ID: <20260515012505.GA3166828@rocinante> References: <20260515005552.2343-1-lirongqing@baidu.com> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260515005552.2343-1-lirongqing@baidu.com> Hello, > The original PCIE_FTS_NUM_L0(x) macro was buggy due to improper operator > precedence, where ((x) & 0xff << 8) was evaluated as ((x) & 0xff00). > > Instead of just fixing the parentheses, use the standard FIELD_PREP() > macro. This makes the code more robust by automatically handling masks > and shifts, while also adding compile-time type and range checking to > ensure the value fits within PCIE_FTS_NUM_MASK. > > Fixes: 637cfacae96f ("PCI: mediatek: Add MediaTek PCIe host controller support") > Signed-off-by: Li RongQing > --- > drivers/pci/controller/pcie-mediatek.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c > index 7572252..00f0e29 100644 > --- a/drivers/pci/controller/pcie-mediatek.c > +++ b/drivers/pci/controller/pcie-mediatek.c > @@ -61,7 +61,7 @@ > /* MediaTek specific configuration registers */ > #define PCIE_FTS_NUM 0x70c > #define PCIE_FTS_NUM_MASK GENMASK(15, 8) > -#define PCIE_FTS_NUM_L0(x) ((x) & 0xff << 8) > +#define PCIE_FTS_NUM_L0(x) FIELD_PREP(PCIE_FTS_NUM_MASK, x) Aww. Nice catch! Thank you for fixing this! Happy to offer: Reviewed-by: Krzysztof Wilczyński All the best, Krzysztof