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=-5.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 7BFC6C46465 for ; Tue, 6 Nov 2018 18:43:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4122820869 for ; Tue, 6 Nov 2018 18:43:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="HiUZtL64" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4122820869 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388034AbeKGEJ6 (ORCPT ); Tue, 6 Nov 2018 23:09:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:40500 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729711AbeKGEJ6 (ORCPT ); Tue, 6 Nov 2018 23:09:58 -0500 Received: from localhost (unknown [104.132.0.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EABA22085B; Tue, 6 Nov 2018 18:43:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541529802; bh=Fvx6KjVoFQkLJdzLtzA5KBqCBUDkRGG9CORC6hsc1zk=; h=To:From:In-Reply-To:Cc:References:Subject:Date:From; b=HiUZtL64QRz78SCBP9g1hMyRE9gyUR+YsL8UyJaIxGVR1jHaS271u+I+QYFVZygLW a93cV/LVwC1kPDlvoXgcqvnnlndHaqY/xpmEinEnsNoLBelAFpuptALnNdw8IdDmzm VmRh54ksV6sgMZQsS1tqKlN9Vt4P/aaYc4K6RM1o= Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable To: Carlo Caione , Jerome Brunet , Kevin Hilman , Neil Armstrong From: Stephen Boyd In-Reply-To: <20181105230820.3562-1-jbrunet@baylibre.com> Cc: Christian Hewitt , Michael Turquette , linux-amlogic@lists.infradead.org, linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, Jerome Brunet References: <20181105230820.3562-1-jbrunet@baylibre.com> Message-ID: <154152980131.88331.14307558394241579493@swboyd.mtv.corp.google.com> User-Agent: alot/0.7 Subject: Re: [PATCH v2] clk: meson-gxbb: set fclk_div3 as CLK_IS_CRITICAL Date: Tue, 06 Nov 2018 10:43:21 -0800 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Quoting Jerome Brunet (2018-11-05 15:08:20) > From: Christian Hewitt > = > On the Khadas VIM2 (GXM) and LePotato (GXL) board there are problems > with reboot; e.g. a ~60 second delay between issuing reboot and the > board power cycling (and in some OS configurations reboot will fail > and require manual power cycling). > = > Similar to 'commit c987ac6f1f088663b6dad39281071aeb31d450a8 ("clk: > meson-gxbb: set fclk_div2 as CLK_IS_CRITICAL")' the SCPI Cortex-M4 > Co-Processor seems to depend on FCLK_DIV3 being operational. > = > Until commit 05f814402d6174369b3b29832cbb5eb5ed287059 ("clk: > meson: add fdiv clock gates"), this clock was modeled and left on by > the bootloader. > = > We don't have precise documentation about the SCPI Co-Processor and > its clock requirement so we are learning things the hard way. > = > Marking this clock as critical solves the problem but it should not > be viewed as final solution. Ideally, the SCPI driver should claim > these clocks. We also depends on some clock hand-off mechanism > making its way to CCF, to make sure the clock stays on between its > registration and the SCPI driver probe. > = > Fixes: 05f814402d61 ("clk: meson: add fdiv clock gates") > Signed-off-by: Christian Hewitt > Signed-off-by: Jerome Brunet > --- I can toss this into clk-fixes?