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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6C630C433F5 for ; Mon, 15 Nov 2021 11:57:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D08B60FE7 for ; Mon, 15 Nov 2021 11:57:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230436AbhKOMAa (ORCPT ); Mon, 15 Nov 2021 07:00:30 -0500 Received: from mail-ed1-f42.google.com ([209.85.208.42]:38891 "EHLO mail-ed1-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230170AbhKOMAY (ORCPT ); Mon, 15 Nov 2021 07:00:24 -0500 Received: by mail-ed1-f42.google.com with SMTP id m20so24857336edc.5; Mon, 15 Nov 2021 03:57:29 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=iZwd8zOKfHOZHtZg1NiyaugaGLTtwcsli/vHUABjgyw=; b=dl20a6pf9ubQUeyNWfyNb6BQCZdr75fb2PvgJJ9jg2yGvZauub9Zi9hkjA42w5YBqB ukMhJ0tIRNIFyMpr2j+qGEE+qxufKdCsctb+tCGB7IPNUa1WYOkFU9OcU7Yt9gd4jklt 1stS8BcCeaKjky4Vz/1DAT03T60/MOAJWBk64S9Wtb8bmsxghm+/AG8Jw6g6y6P4sN0O X6UU2aFHiq3mBB8sSeJIVb94Fv5xOkZvFhBID19tlFJw9nXAvao5Kk5JowAIIy2enmpy bhLAc/V1tIvCx1VSlvfn9phhcG/N//AI2tL+xtvPV2flEOLXCrOWxeuAxqnzRzDkxGNJ GN7A== X-Gm-Message-State: AOAM531S+TJCPWs6VxSnk/wdaLmAUdwoarqPAjLZncgi5YN5jOIbZKev k9fzejdpaCkuKLeVonrewm8= X-Google-Smtp-Source: ABdhPJwW6w4WpnROjobFjseOxEMIFpGxpb+OUZBqnh8kfqVJtqdI09J1Lvv5euWDTqz0D+G9VGmPuQ== X-Received: by 2002:a17:906:b055:: with SMTP id bj21mr47736793ejb.292.1636977448502; Mon, 15 Nov 2021 03:57:28 -0800 (PST) Received: from rocinante ([95.155.85.46]) by smtp.gmail.com with ESMTPSA id ne33sm6491674ejc.6.2021.11.15.03.57.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Nov 2021 03:57:27 -0800 (PST) Date: Mon, 15 Nov 2021 12:57:26 +0100 From: Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= To: Andy Shevchenko Cc: bcm-kernel-feedback-list@broadcom.com, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Jim Quinlan , Nicolas Saenz Julienne , Florian Fainelli , Lorenzo Pieralisi , Rob Herring , Bjorn Helgaas Subject: Re: [PATCH v2 1/1] PCI: brcmstb: Use BIT() as __GENMASK() is for internal use only Message-ID: References: <20211115112000.23693-1-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20211115112000.23693-1-andriy.shevchenko@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Andy, > Use BIT() as __GENMASK() is for internal use only. The rationale > of switching to BIT() is to provide better generated code. The > GENMASK() against non-constant numbers may produce an ugly assembler > code. On contrary the BIT() is simply converted to corresponding shift > operation. > > Note, it's the only user of __GENMASK() in the kernel outside of its own realm. > > Fixes: 3baec684a531 ("PCI: brcmstb: Accommodate MSI for older chips") > Signed-off-by: Andy Shevchenko > --- > v2: switched to BIT() and elaborated why, hence not included tag > drivers/pci/controller/pcie-brcmstb.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c > index 1fc7bd49a7ad..0c49fc65792c 100644 > --- a/drivers/pci/controller/pcie-brcmstb.c > +++ b/drivers/pci/controller/pcie-brcmstb.c > @@ -619,7 +619,7 @@ static void brcm_msi_remove(struct brcm_pcie *pcie) > > static void brcm_msi_set_regs(struct brcm_msi *msi) > { > - u32 val = __GENMASK(31, msi->legacy_shift); > + u32 val = ~(BIT(msi->legacy_shift) - 1); Thank you! I also personally prefer using BIT() macro here. Reviewed-by: Krzysztof Wilczyński Krzysztof