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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED 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 05B72C48BD5 for ; Wed, 26 Jun 2019 01:05:48 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CD90E208CA for ; Wed, 26 Jun 2019 01:05:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="BwPtDTqH" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CD90E208CA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Date:To:From:Subject:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=SDAlcHTRrTsWxRsKL89lBafcbvcr17ncNlB2T6OPWE4=; b=BwPtDTqH78ooBM xR42QroAFy1THZirA82itzRybOLjt7Q+FtEyW/RMujYfSNSmHzvH/hOeEhw8uODMQAzeVvzNsVsFH bWLTDUu4q78uBh4r7D2/epQ4jABw2Xw/RkxGWytaMrkQkcg7t32Zv6wBq5VojVwwUS8Ukdbz3xxqg /iat3GTpjwn1v+SgozPhpU5PWzHMHfkctkL5f3ZK53B1JVQ0VuGWjYIBRbDX5VVwnizGYOpmiT1Mr qEenjHUVSuO1PvhsIsmu/3bcSfIeQJvskQe52oyWKufJFV3zDZzI9S4ooHLHcO3+UtYwgtAQqhlOg N4/j3jR5h9U8k2LtBE7Q==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hfwNZ-0004Qb-F5; Wed, 26 Jun 2019 01:05:41 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hfwNV-0004Ok-1o; Wed, 26 Jun 2019 01:05:39 +0000 X-UUID: d066b5c35866476aa075657f9dda9867-20190625 X-UUID: d066b5c35866476aa075657f9dda9867-20190625 Received: from mtkcas66.mediatek.inc [(172.29.193.44)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLS) with ESMTP id 712194665; Tue, 25 Jun 2019 17:05:30 -0800 Received: from MTKMBS01N1.mediatek.inc (172.21.101.68) by MTKMBS62N1.mediatek.inc (172.29.193.41) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 25 Jun 2019 18:05:29 -0700 Received: from MTKCAS06.mediatek.inc (172.21.101.30) by mtkmbs01n1.mediatek.inc (172.21.101.68) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Wed, 26 Jun 2019 09:05:22 +0800 Received: from [172.21.77.4] (172.21.77.4) by MTKCAS06.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Wed, 26 Jun 2019 09:05:22 +0800 Message-ID: <1561511122.24282.10.camel@mtksdaap41> Subject: Re: [RFC v1] clk: core: support clocks that need to be enabled during re-parent From: Weiyi Lu To: Stephen Boyd Date: Wed, 26 Jun 2019 09:05:22 +0800 In-Reply-To: <20190625221415.B0DC22086D@mail.kernel.org> References: <1560138293-4163-1-git-send-email-weiyi.lu@mediatek.com> <20190625221415.B0DC22086D@mail.kernel.org> X-Mailer: Evolution 3.10.4-0ubuntu2 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190625_180537_949217_39FFE864 X-CRM114-Status: GOOD ( 12.75 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: James Liao , srv_heupstream@mediatek.com, Biao Huang , linux-kernel@vger.kernel.org, Fan Chen , linux-mediatek@lists.infradead.org, Matthias Brugger , linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, 2019-06-25 at 15:14 -0700, Stephen Boyd wrote: > Quoting Weiyi Lu (2019-06-09 20:44:53) > > When using property assigned-clock-parents to assign parent clocks, > > core clocks might still be disabled during re-parent. > > Add flag 'CLK_OPS_CORE_ENABLE' for those clocks must be enabled > > during re-parent. > > > > Signed-off-by: Weiyi Lu > > Can you further describe the scenario where this is a problem? Is it > some sort of clk that is enabled by default out of the bootloader and is > then configured to have an 'assigned-clock-parents' property to change > the parent, but that clk needs to be "enabled" so that the framework > turns on the parents for the parent switch? When driver is built as module(.ko) and install at runtime after the whole initialization stage. Clk might already be turned off before configuring by assigned-clock-parents. For such clock design that need to have clock enabled during re-parent, the configuration of assigned-clock-parents might be failed. That's the problem we have now. Do you have any suggestion for such usage of clocks? Many thanks. > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel