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=-12.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=ham 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 5533DC4338F for ; Thu, 22 Jul 2021 19:05:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 385BF60EBD for ; Thu, 22 Jul 2021 19:05:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230291AbhGVSY7 (ORCPT ); Thu, 22 Jul 2021 14:24:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230261AbhGVSY6 (ORCPT ); Thu, 22 Jul 2021 14:24:58 -0400 Received: from mail-ot1-x32e.google.com (mail-ot1-x32e.google.com [IPv6:2607:f8b0:4864:20::32e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0E325C061757 for ; Thu, 22 Jul 2021 12:05:32 -0700 (PDT) Received: by mail-ot1-x32e.google.com with SMTP id s2-20020a0568301e02b02904ce2c1a843eso6246346otr.13 for ; Thu, 22 Jul 2021 12:05:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:in-reply-to:references:from:user-agent:date:message-id :subject:to:cc; bh=congdFIKNx3UQvjcKCH7cpv7zvqp5GO1L/NygEo3sXY=; b=dDIPDFkyDDHfqVGTpIk+wx1GBgHwuS+5k3bX78JBMROdG0Il9Fa6gFRE3N4NL2Qk0f SqQZg2RIPA064hM8VFnMY2q+vHBzUFSnc7iN5K2p7p4BJ7A/sYHwrrcq3pXBnJC7CkMX 6ETr8WW+bTfkdyUukPtX19G0Yed7uhKTttRjU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from :user-agent:date:message-id:subject:to:cc; bh=congdFIKNx3UQvjcKCH7cpv7zvqp5GO1L/NygEo3sXY=; b=ilsS0aF7diMkDpVw//biQ0AK+Vxy1vk3T6QBT2oAz+AsU/k/I99FbgOKn8zvSycFAX orYfrY3zCD5bC/1uPf45rgz+aLsPotg7sFs58DS/U4Iss6JpyYUi9yOUm05ZgWIemVpp 5Zfi7/3PjexvXTy/hDXIO2NHx4OUvfltwPFqFk9b069pEWxIKMmxAradYVFyT51POHpH 1iQwDXnFBK1xOU6dGDy4R09+8fNkfW12B6KZb/t7r6iBbYdi3F4RlMTbUVMevo+Vq5u2 RdKmViieYTCoEPv4iST074aHU42pk5euZOqPG7/lA6SzUheT5NKaJJJwlm9myMLn4Plm 4SlQ== X-Gm-Message-State: AOAM530QpZe3hbqvby2jyrKH0P87PiDc9LjSwpYipYAdt2ES5g78k1U2 fwssrjt8LzCHwLWncqmlpuxk+i6Q64lv4wwpqTCkKQ== X-Google-Smtp-Source: ABdhPJxszP1Nvb9QVLAphQ4FMRQGZNgHTiAOHsXtE6VBCSK4Mkx8qQEaF06I/qJbcI+d9b6gULejIcgtbhtlsXTT8NA= X-Received: by 2002:a9d:8c7:: with SMTP id 65mr842433otf.25.1626980731332; Thu, 22 Jul 2021 12:05:31 -0700 (PDT) Received: from 753933720722 named unknown by gmailapi.google.com with HTTPREST; Thu, 22 Jul 2021 19:05:30 +0000 MIME-Version: 1.0 In-Reply-To: <1626191647-13901-3-git-send-email-khsieh@codeaurora.org> References: <1626191647-13901-1-git-send-email-khsieh@codeaurora.org> <1626191647-13901-3-git-send-email-khsieh@codeaurora.org> From: Stephen Boyd User-Agent: alot/0.9.1 Date: Thu, 22 Jul 2021 19:05:30 +0000 Message-ID: Subject: Re: [PATCH v2 2/7] drm/msm/dp: reduce link rate if failed at link training 1 To: Kuogee Hsieh , dri-devel@lists.freedesktop.org, robdclark@gmail.com, sean@poorly.run Cc: abhinavk@codeaurora.org, aravindh@codeaurora.org, airlied@linux.ie, daniel@ffwll.ch, bjorn.andersson@linaro.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Quoting Kuogee Hsieh (2021-07-13 08:54:02) > diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c > index 27fb0f0..92cf331 100644 > --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c > +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c > @@ -1634,6 +1617,24 @@ void dp_ctrl_handle_sink_request(struct dp_ctrl *dp_ctrl) > } > } > > +static bool dp_ctrl_clock_recovery_any_ok( > + const u8 link_status[DP_LINK_STATUS_SIZE], > + int lane_count) > +{ > + int lane_cnt; > + > + /* > + * only interested in the lane number after reduced > + * lane_cnt = 4, then only interested in 2 lanes > + * lane_cnt = 2, then only interested in 1 lane > + */ > + lane_cnt = lane_count >> 1; > + if (lane_cnt == 0) > + return false; > + > + return drm_dp_clock_recovery_ok(link_status, lane_count); This doesn't work? Because drm_dp_clock_recovery_ok() requires every lane to be OK whereas this function wants any lane to be OK? It may make sense to have drm_dp_clock_recovery_ok() return false if lane_count == 0 too. > +} > + > int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl) > { > int rc = 0;