From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752225AbdAYSdp (ORCPT ); Wed, 25 Jan 2017 13:33:45 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:34752 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751634AbdAYSdm (ORCPT ); Wed, 25 Jan 2017 13:33:42 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org E2B6160864 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=okaya@codeaurora.org Subject: Re: [PATCH] PCI: enable extended tags support for PCIe endpoints To: Bjorn Helgaas References: <1474769434-5756-1-git-send-email-okaya@codeaurora.org> <420a9a23-79f8-41d8-c44f-b53f5000c957@codeaurora.org> <20161111205801.GC9868@bhelgaas-glaptop.roam.corp.google.com> <34f2e149-3bb1-6af2-a9f5-fbe5a050fe31@codeaurora.org> Cc: linux-pci@vger.kernel.org, timur@codeaurora.org, cov@codeaurora.org, vikrams@codeaurora.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org From: Sinan Kaya Message-ID: <84d599dc-e371-7273-4bda-feb9c9eb8014@codeaurora.org> Date: Wed, 25 Jan 2017 13:33:39 -0500 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.6.0 MIME-Version: 1.0 In-Reply-To: <34f2e149-3bb1-6af2-a9f5-fbe5a050fe31@codeaurora.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/25/2017 12:49 PM, Sinan Kaya wrote: > Hi Bjorn, > > On 11/11/2016 3:58 PM, Bjorn Helgaas wrote: >>> Is there any other feedback? >> If this were completely safe to enable for every device that supported >> it, why would there be an enable bit in Device Control? >> >> I don't know anything about extended tags, but it worries me a little >> when there's a "go-fast" switch and no explanation about when and why >> we might need to go slow. >> I tried to answer your question in the new commit message. All PCIe completers are required to support 8 bit tags. Generation of 8 bit tags is optional. That's why, there is a supported and an enable/disable bit. > > I have v2 posted. Do you feel like applying to linux-next to get some testing > exposure or do you want to tie it to some DMI so that we enable it only on > recent HW? > > Sinan > -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.