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=-10.5 required=3.0 tests=BAYES_00,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,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 C98B6C07E9C for ; Wed, 14 Jul 2021 07:58:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ACDC76135A for ; Wed, 14 Jul 2021 07:58:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238400AbhGNIBs (ORCPT ); Wed, 14 Jul 2021 04:01:48 -0400 Received: from mail-wr1-f45.google.com ([209.85.221.45]:46978 "EHLO mail-wr1-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238287AbhGNIBq (ORCPT ); Wed, 14 Jul 2021 04:01:46 -0400 Received: by mail-wr1-f45.google.com with SMTP id d12so1984265wre.13; Wed, 14 Jul 2021 00:58:54 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=w1b6wrWBKDKa+tZj2BRGOgdt3If+IOv+NClRdPNKcBM=; b=i8TEsoj8sokpDLOGUixv3RBwmDnYqp9xviN9mTQUnaPfIzBJIr7giU1BeIDV0PYmam g9EjK8yBDymEsmDIAvChYJOB0PX8rBGkKYo7uPXpc0sRokQCV1zi1c/Vk7vg/edVuVH6 8FZOZyc6Y3Gh1BRDDE/pSWfwRXsY3PswKWsrdBVksn9IVs1iACUBLPPO9v9pw6q0orh1 +3uQY3kIU7laj2zmlQO3BegrGGYUyUl2/ZvOlqWdrEWVp1MINUwXTlaJElDrSAVjsXl+ 9HqlMyWkQ1F2TuzS6fc3wWxdhuD1jc2LS20slwh680bTBiTkco+YHhL+Fvl+/o+Qui2r bG4g== X-Gm-Message-State: AOAM531Su37pjqoLE2hCEC1C6X1oudHLqzIp7AmE6WWiKc/yIhjUPOa4 4mAxj8jCCLjan5bYdAFgwoSx/wDtP8nSHQ== X-Google-Smtp-Source: ABdhPJwPiZtOidE+kXKOB8zP/AitNMoyELHpBDkGKEgZ8xjPkTHgfAPY2I0Fhi98OW30ehHRa+RbxA== X-Received: by 2002:adf:eacb:: with SMTP id o11mr11844778wrn.62.1626249534391; Wed, 14 Jul 2021 00:58:54 -0700 (PDT) Received: from ?IPv6:2a0b:e7c0:0:107::70f? ([2a0b:e7c0:0:107::70f]) by smtp.gmail.com with ESMTPSA id h9sm1265193wmb.35.2021.07.14.00.58.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 14 Jul 2021 00:58:53 -0700 (PDT) Subject: Re: [PATCH v1 3/4] serial: 8250_pci: Always try MSI/MSI-X From: Jiri Slaby To: Andy Shevchenko , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , Ralf Ramsauer References: <20210713104026.58560-1-andriy.shevchenko@linux.intel.com> <20210713104026.58560-3-andriy.shevchenko@linux.intel.com> <9af24b96-8119-7ccf-f0d0-d725af80aa0b@kernel.org> Message-ID: <33767cf0-2104-d7aa-2da8-5a3f5f20a654@kernel.org> Date: Wed, 14 Jul 2021 09:58:52 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <9af24b96-8119-7ccf-f0d0-d725af80aa0b@kernel.org> Content-Type: text/plain; charset=iso-8859-2; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14. 07. 21, 8:54, Jiri Slaby wrote: >> @@ -3994,14 +3982,9 @@ pciserial_init_ports(struct pci_dev *dev, const >> struct pciserial_board *board) >>       if (board->flags & FL_NOIRQ) { >>           uart.port.irq = 0; >>       } else { >> -        if (pci_match_id(pci_use_msi, dev)) { >> -            dev_dbg(&dev->dev, "Using MSI(-X) interrupts\n"); >> -            pci_set_master(dev); >> -            rc = pci_alloc_irq_vectors(dev, 1, 1, PCI_IRQ_ALL_TYPES); >> -        } else { >> -            dev_dbg(&dev->dev, "Using legacy interrupts\n"); >> -            rc = pci_alloc_irq_vectors(dev, 1, 1, PCI_IRQ_LEGACY); >> -        } >> +        pci_set_master(dev); > > But bus mastering is not about MSIs. I *think* it's still OK, but you > need to document that in the commit log too. > > Actually, why the commit which added this code turns on bus mastering? Forget about this line, I wasn't woken enough. Of course, MSI (writes) to bus need bus mastering. In any case, I'm still not sure what happens to devices which do not support MSI if we enable mastering on them? -- js suse labs