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, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 EF252C433DB for ; Thu, 14 Jan 2021 22:40:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BC2CA23A5C for ; Thu, 14 Jan 2021 22:40:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730759AbhANWko (ORCPT ); Thu, 14 Jan 2021 17:40:44 -0500 Received: from relay05.th.seeweb.it ([5.144.164.166]:42535 "EHLO relay05.th.seeweb.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730608AbhANWkn (ORCPT ); Thu, 14 Jan 2021 17:40:43 -0500 Received: from IcarusMOD.eternityproject.eu (unknown [2.237.20.237]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by m-r2.th.seeweb.it (Postfix) with ESMTPSA id 1BB0C3F116; Thu, 14 Jan 2021 23:40:02 +0100 (CET) Subject: Re: [PATCH 1/9] clk: qcom: gcc-msm8998: Wire up gcc_mmss_gpll0 clock To: Jeffrey Hugo Cc: MSM , konrad.dybcio@somainline.org, marijn.suijten@somainline.org, martin.botka@somainline.org, phone-devel@vger.kernel.org, lkml , Andy Gross , Bjorn Andersson , Michael Turquette , Stephen Boyd , Rob Herring , linux-clk@vger.kernel.org, DTML References: <20210109134617.146275-1-angelogioacchino.delregno@somainline.org> <20210109134617.146275-2-angelogioacchino.delregno@somainline.org> <9942f98c-c186-5cd0-d6ac-a18a4e20583e@somainline.org> From: AngeloGioacchino Del Regno Message-ID: Date: Thu, 14 Jan 2021 23:40:01 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Il 14/01/21 23:33, Jeffrey Hugo ha scritto: > On Thu, Jan 14, 2021 at 3:13 PM AngeloGioacchino Del Regno > wrote: >> >> Il 14/01/21 23:12, Jeffrey Hugo ha scritto: >>> On Sat, Jan 9, 2021 at 6:47 AM AngeloGioacchino Del Regno >>> wrote: >>>> >>>> This clock enables the GPLL0 output to the multimedia subsystem >>>> clock controller. >>>> >>>> Signed-off-by: AngeloGioacchino Del Regno >>> >>> Any reason why you are not also adding the div_clk? >>> >> >> Yes, just one: I haven't tested it... and my devices worked without. >> Perhaps we can add it whenever we find out if something really needs it? > > I'm mildly surprised you need to turn on the gate to the PLL0 out, but > not the div_out. The div_out/div_clk is also fed into every RCG that > exists in the MMCC. > > Per the frequency plan the following RCGs require it - > > cci > cpp > fd_core > camss_gp[0-1] > jpeg0 > mclk[0-3] > csi[0-2]phytimer > dp_gtc > maxi > axi > ahb > > Also, I'm very interested in all things 8998, and would generally > appreciate being added to the to: list. > To be honest, I was surprised as well because.. yes, I know that these RCGs seem to need it, but then their clock tables don't contain any reference to the gpll0 divider, hence it's never getting used - and that works great, for now. I am aware of the fact that the clocks that you've mentioned are using the divider to reduce jitter, but I haven't done any camera test on my devices yet: that's definitely in my plans and I really can't wait to do that (as I successfully did for SDM630/660), but... we have more than 100 patches in our trees. We need to get upstream in the same working order as what we have here, so that we don't diverge that much and our work is kept in a maintainable state (avoiding to lose pieces around). I'm sure that I'll send a commit adding the gpll0 divider branch as soon as I will start the camera work: I feel it, it's going to give me issues without, in that field. By the way, noted. I'll make sure to add you in the to/cc for all of the next series regarding 8998 that I'll send. Meanwhile, you may want to check out all the recent patches that I've sent, as like 90% are MSM8998-centric... :)) -- Angelo