From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 99109C4743C for ; Wed, 23 Jun 2021 08:52:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7EB2B6120D for ; Wed, 23 Jun 2021 08:52:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229833AbhFWIyo (ORCPT ); Wed, 23 Jun 2021 04:54:44 -0400 Received: from foss.arm.com ([217.140.110.172]:60002 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230001AbhFWIyn (ORCPT ); Wed, 23 Jun 2021 04:54:43 -0400 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 EEAC731B; Wed, 23 Jun 2021 01:52:25 -0700 (PDT) Received: from lpieralisi (e121166-lin.cambridge.arm.com [10.1.196.255]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id ED0CC3F719; Wed, 23 Jun 2021 01:52:24 -0700 (PDT) Date: Wed, 23 Jun 2021 09:52:14 +0100 From: Lorenzo Pieralisi To: Bjorn Helgaas Cc: Jon Hunter , Bjorn Helgaas , Thierry Reding , Vidya Sagar , linux-pci@vger.kernel.org, linux-tegra@vger.kernel.org Subject: Re: [PATCH] PCI: tegra: Fix shiftTooManyBitsSigned warning for Tegra194 Message-ID: <20210623085206.GA10593@lpieralisi> References: <20210618160219.303092-1-jonathanh@nvidia.com> <20210618230428.GA3231877@bjorn-Precision-5520> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210618230428.GA3231877@bjorn-Precision-5520> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-tegra@vger.kernel.org On Fri, Jun 18, 2021 at 06:04:28PM -0500, Bjorn Helgaas wrote: > On Fri, Jun 18, 2021 at 05:02:19PM +0100, Jon Hunter wrote: > > The cppcheck tool issues the following warning for the Tegra194 PCIe > > driver ... > > > > $ cppcheck --enable=all drivers/pci/controller/dwc/pcie-tegra194.c > > Checking drivers/pci/controller/dwc/pcie-tegra194.c ... > > > > drivers/pci/controller/dwc/pcie-tegra194.c:1829:23: portability: > > Shifting signed 32-bit value by 31 bits is > > implementation-defined behaviour. See condition at line 1826. > > [shiftTooManyBitsSigned] > > > > appl_writel(pcie, (1 << irq), APPL_MSI_CTRL_1); > > ^ > > The above warning occurs because the '1' is treated as a signed type > > and so fix this by using the 'BIT' macro to ensure that this is defined > > as a unsigned type. > > The subject and commit log should describe the problem we're fixing. > The *warning* is not the problem; the problem is the undefined > behavior. > > I'll fix this up, no need to repost for this. Hi Bjorn, I can fix it up myself, just wanted to ask if you merged it already, it does not look like but I thought I'd check. Thanks, Lorenzo > > Fixes: c57247f940e8 PCI: tegra: Add support for PCIe endpoint mode in Tegra194 > > Signed-off-by: Jon Hunter > > --- > > drivers/pci/controller/dwc/pcie-tegra194.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c > > index 8fc08336f76e..3c1feeab104f 100644 > > --- a/drivers/pci/controller/dwc/pcie-tegra194.c > > +++ b/drivers/pci/controller/dwc/pcie-tegra194.c > > @@ -1826,7 +1826,7 @@ static int tegra_pcie_ep_raise_msi_irq(struct tegra_pcie_dw *pcie, u16 irq) > > if (unlikely(irq > 31)) > > return -EINVAL; > > > > - appl_writel(pcie, (1 << irq), APPL_MSI_CTRL_1); > > + appl_writel(pcie, BIT(irq), APPL_MSI_CTRL_1); > > > > return 0; > > } > > -- > > 2.25.1 > >