From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755901AbcEYSTH (ORCPT ); Wed, 25 May 2016 14:19:07 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:52707 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751523AbcEYSTF (ORCPT ); Wed, 25 May 2016 14:19:05 -0400 Subject: Re: [PATCH] PCI/ASPM: fix reverse ASPM L0s assignment of upstream and downstream To: Bjorn Helgaas References: <1464071269-79954-1-git-send-email-hehy1@lenovo.com> <20160525165726.GB3208@localhost> <5745DF08.9040409@codeaurora.org> <20160525175039.GC3208@localhost> Cc: Ocean HY1 He , "bhelgaas@google.com" , "wangyijing@huawei.com" , "luto@kernel.org" , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "prarit@redhat.com" , "jcm@redhat.com" , Nagananda Chumbalkar From: Sinan Kaya Message-ID: <5745EC95.1020506@codeaurora.org> Date: Wed, 25 May 2016 14:19:01 -0400 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.7.2 MIME-Version: 1.0 In-Reply-To: <20160525175039.GC3208@localhost> 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 5/25/2016 1:50 PM, Bjorn Helgaas wrote: >> > You are saying that it is OK to enable L0s on just one side of the >> > link as long as both sides support L0s. > I'm not sure what you mean by the link parameters not being > compatible, but I think it is legal to enable L0s on only one > direction. I'm talking about L0s acceptable and entry latency times used to determine when L0s can be enabled. > >> > This part is a little bit misleading. I had HW people telling me >> > that both sides need to enable L0s at about the same time. > I don't remember seeing anything like that in the spec. Do they have > a pointer? "At about the same time" is too hand-wavey to be useful to > software. > OK. Let me do some more push back. I wanted to understand the OS behavior and its reasoning. Your answers are sufficient. -- Sinan Kaya Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project