From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751725AbeA2JXF (ORCPT ); Mon, 29 Jan 2018 04:23:05 -0500 Received: from mail-wm0-f53.google.com ([74.125.82.53]:40931 "EHLO mail-wm0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751649AbeA2JXB (ORCPT ); Mon, 29 Jan 2018 04:23:01 -0500 X-Google-Smtp-Source: AH8x225Ll3nh5EA98Xc6uZGyy/QLVc9hi4yjA2t3PDY3wq4o1pOwVei73KyK/V+v7OHDZ39CP/eAYg== Message-ID: <1517217778.3153.1.camel@baylibre.com> Subject: Re: [PATCH v5 00/10] clk: implement clock rate protection mechanism From: Jerome Brunet To: Stephen Boyd , Michael Turquette Cc: linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, Russell King , Linus Walleij , Quentin Schulz , Kevin Hilman , Maxime Ripard Date: Mon, 29 Jan 2018 10:22:58 +0100 In-Reply-To: <20171222021520.GO7997@codeaurora.org> References: <20171201215200.23523-1-jbrunet@baylibre.com> <151373031022.33554.13905466641279532222@resonance> <20171222021520.GO7997@codeaurora.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.4 (3.26.4-1.fc27) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2017-12-21 at 18:15 -0800, Stephen Boyd wrote: > On 12/19, Michael Turquette wrote: > > Quoting Jerome Brunet (2017-12-01 13:51:50) > > > This Patchset is related the RFC [0] and the discussion around > > > CLK_SET_RATE_GATE available here [1] > > > > > > This patchset introduce clock protection to the CCF core. This can then > > > be used for: > > > > > > * Provide a way for a consumer to claim exclusivity over the rate control > > > of a provider. Some clock consumers require that a clock rate must not > > > deviate from its selected frequency. There can be several reasons for > > > this, not least of which is that some hardware may not be able to > > > handle or recover from a glitch caused by changing the clock rate while > > > the hardware is in operation. For such HW, The ability to get exclusive > > > control of a clock's rate, and release that exclusivity, could be seen > > > as a fundamental clock rate control primitive. The exclusivity is not > > > preemptible, so when claimed more than once, is rate is effectively > > > locked. > > > > > > * Provide a similar functionality to providers themselves, fixing > > > CLK_SET_RATE_GATE flag (enforce clock gating along the tree). While > > > there might still be a few platforms relying the broken implementation, > > > tests done has shown this change to be pretty safe. > > > > Applied to clk-protect-rate, with the exception that I did not apply > > "clk: fix CLK_SET_RATE_GATE with clock rate protection" as it breaks > > qcom clk code. > > > > Stephen, do you plan to fix up the qcom clock code so that the > > SET_RATE_GATE improvement can go in? > > > > I started working on it a while back. Let's see if I can finish > it off this weekend. > Hi Stephen, Have you been able find something to fix the qcom code regarding this issue ? Cheers Jerome