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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B614EC25B0E for ; Mon, 15 Aug 2022 15:43:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232227AbiHOPnJ (ORCPT ); Mon, 15 Aug 2022 11:43:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59786 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232598AbiHOPnA (ORCPT ); Mon, 15 Aug 2022 11:43:00 -0400 Received: from wout2-smtp.messagingengine.com (wout2-smtp.messagingengine.com [64.147.123.25]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8562634E for ; Mon, 15 Aug 2022 08:42:59 -0700 (PDT) Received: from compute2.internal (compute2.nyi.internal [10.202.2.46]) by mailout.west.internal (Postfix) with ESMTP id 6EC923200805; Mon, 15 Aug 2022 11:42:58 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute2.internal (MEProxy); Mon, 15 Aug 2022 11:42:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cerno.tech; h=cc :cc:content-transfer-encoding:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:sender :subject:subject:to:to; s=fm3; t=1660578177; x=1660664577; bh=XE bIbhyV7aE+7IA/urdiz2t84U2kdZcEK95CYglOfzg=; b=DurHb/FgEp2JzmvnkB JT6xT85dRYGkzaIpkFjDv/mafIz3rdEkEaWcr+wMj4uaMx2JFb6TUzZl1VlC3vVx l6kUDe6VwPbTIQV3xhfUkNztlX1/mIhJsjqoBmAfwQjQ5UuNG2IzUlA0Doz7Tejm nuj0XxEOaosAdi2NkN+97NBg+JEC/KavvGb+pFS2w35Z7uKBzq9xiuicCIgJZPOZ C0NMm8xYCY+IcWLf8y02/62geJ2lM04j+a890/F76gJFc2NxKigwHpD6N4JoJx8+ ytrOUwlg5BAK+8n4aqClJf5aj2PBmikZbSjRkprLJ+KFBBXqsFu2ssxmPRuBAAGN hspg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm1; t=1660578177; x=1660664577; bh=XEbIbhyV7aE+7 IA/urdiz2t84U2kdZcEK95CYglOfzg=; b=3Gq7z1Pm9mFm42X2Xhbon8c8ysLN1 hiB9F7RFXXIaOm5z52WgtRsGaaZbZJh53v0SppZdQ9dEZMVPY1dprbSgjDv43vas rdo1QuxFCUjGwVRVzKwENXduzJMppGsMQw/Ezjq/mAqBL5hwzzmkpa+i9R/Rm2we Jo9HPXqBV9+kcZIlwxw8MAJKp+syu5+jdIjfr1NOp/YJNifnN6xuTvaetcw9MlWe aGnI1op7Vm5Ayk720272GhqCZF7+FMUrvoLf6nxyOM5Ck9pYBROoWiTLtsEXBizU jswRtTK/8+Y13Fh+2z0Xm+sf4x/JA2DJms/BJkqHPLHNeb2mpMtXQD+mg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvfedrvdehvddgleefucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhephffvvefufffkofgjfhgggfestdekredtredttdenucfhrhhomhepofgrgihi mhgvucftihhprghrugcuoehmrgigihhmvgestggvrhhnohdrthgvtghhqeenucggtffrrg htthgvrhhnpeelkeefteduhfekjeeihfetudfguedvveekkeetteekhfekhfdtlefgfedu vdejhfenucevlhhushhtvghrufhiiigvpeegnecurfgrrhgrmhepmhgrihhlfhhrohhmpe hmrgigihhmvgestggvrhhnohdrthgvtghh X-ME-Proxy: Feedback-ID: i8771445c:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Mon, 15 Aug 2022 11:42:57 -0400 (EDT) From: Maxime Ripard To: linux-clk@vger.kernel.org, Mike Turquette , Stephen Boyd Cc: Tony Lindgren , Jerome Brunet , Neil Armstrong , Yassine Oudjana , Dmitry Baryshkov , Marek Szyprowski , Naresh Kamboju , Alexander Stein , Maxime Ripard Subject: [PATCH v8 15/25] clk: Move clk_core_init_rate_req() from clk_core_round_rate_nolock() to its caller Date: Mon, 15 Aug 2022 17:41:37 +0200 Message-Id: <20220815154147.1631441-16-maxime@cerno.tech> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220815154147.1631441-1-maxime@cerno.tech> References: <20220815154147.1631441-1-maxime@cerno.tech> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org The clk_rate_request structure is used internally as an argument for the clk_core_determine_round_nolock() and clk_core_round_rate_nolock(). In both cases, the clk_core_init_rate_req() function is used to initialize the clk_rate_request structure. However, the expectation on who gets to call that function is inconsistent between those two functions. Indeed, clk_core_determine_round_nolock() will assume the structure is properly initialized and will just use it. On the other hand, clk_core_round_rate_nolock() will call clk_core_init_rate_req() itself, expecting the caller to have filled only a minimal set of parameters (rate, min_rate and max_rate). If we ignore the calling convention inconsistency, this leads to a second inconsistency for drivers: * If they get called by the framework through clk_core_round_rate_nolock(), the rate, min_rate and max_rate fields will be filled by the caller, and the best_parent_rate and best_parent_hw fields will get filled by clk_core_init_rate_req(). * If they get called by a driver through __clk_determine_rate (and thus clk_core_round_rate_nolock), only best_parent_rate and best_parent_hw are being explicitly set by the framework. Even though we can reasonably expect rate to be set, only one of the 6 in-tree users explicitly set min_rate and max_rate. * If they get called by the framework through clk_core_determine_round_nolock(), then we have two callpaths. Either it will be called by clk_core_round_rate_nolock() itself, or it will be called by clk_calc_new_rates(), which will properly initialize rate, min_rate, max_rate itself, and best_parent_rate and best_parent_hw through clk_core_init_rate_req(). Even though the first and third case seems equivalent, they aren't when the clock has CLK_SET_RATE_PARENT. Indeed, in such a case clk_core_round_rate_nolock() will call itself on the current parent clock with the same clk_rate_request structure. The clk_core_init_rate_req() function will then be called on the parent clock, with the child clk_rate_request pointer and will fill the best_parent_rate and best_parent_hw fields with the parent context. When the whole recursion stops and the call returns, the initial caller will end up with a clk_rate_request structure with some informations of the child clock (rate, min_rate, max_rate) and some others of the last clock up the tree whose child had CLK_SET_RATE_PARENT (best_parent_hw, best_parent_rate). In the most common case, best_parent_rate is going to be equal on all the parent clocks so it's not a big deal. However, best_parent_hw is going to point to a clock that never has been a valid parent for that clock which is definitely confusing. In order to fix the calling inconsistency, let's move the clk_core_init_rate_req() calls to the callers, which will also help a bit with the clk_core_round_rate_nolock() recursion. Tested-by: Alexander Stein # imx8mp Tested-by: Marek Szyprowski # exynos4210, meson g12b Signed-off-by: Maxime Ripard --- drivers/clk/clk.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 6670e61edb31..7a071c567800 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -1415,8 +1415,6 @@ static int clk_core_round_rate_nolock(struct clk_core *core, return 0; } - clk_core_init_rate_req(core, req, req->rate); - if (clk_core_can_round(core)) return clk_core_determine_round_nolock(core, req); else if (core->flags & CLK_SET_RATE_PARENT) @@ -1464,8 +1462,8 @@ unsigned long clk_hw_round_rate(struct clk_hw *hw, unsigned long rate) int ret; struct clk_rate_request req; + clk_core_init_rate_req(hw->core, &req, rate); clk_core_get_boundaries(hw->core, &req.min_rate, &req.max_rate); - req.rate = rate; ret = clk_core_round_rate_nolock(hw->core, &req); if (ret) @@ -1497,8 +1495,8 @@ long clk_round_rate(struct clk *clk, unsigned long rate) if (clk->exclusive_count) clk_core_rate_unprotect(clk->core); + clk_core_init_rate_req(clk->core, &req, rate); clk_core_get_boundaries(clk->core, &req.min_rate, &req.max_rate); - req.rate = rate; ret = clk_core_round_rate_nolock(clk->core, &req); @@ -2206,8 +2204,8 @@ static unsigned long clk_core_req_round_rate_nolock(struct clk_core *core, if (cnt < 0) return cnt; + clk_core_init_rate_req(core, &req, req_rate); clk_core_get_boundaries(core, &req.min_rate, &req.max_rate); - req.rate = req_rate; ret = clk_core_round_rate_nolock(core, &req); -- 2.37.1