From patchwork Tue Apr 5 07:28:40 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 556906 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 34D5FC433F5 for ; Tue, 5 Apr 2022 11:33:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377420AbiDEL3J (ORCPT ); Tue, 5 Apr 2022 07:29:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33260 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350071AbiDEJwk (ORCPT ); Tue, 5 Apr 2022 05:52:40 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8ED5148893; Tue, 5 Apr 2022 02:50:42 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 180B7615E3; Tue, 5 Apr 2022 09:50:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 28E26C385A1; Tue, 5 Apr 2022 09:50:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649152241; bh=pONLUX1/XreyVe65IKeyG1wQLSMZqhZ3jM/+bDVog24=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DzusMr6dAkVj+bAMRNOIm13oh6H3/1pmIxhMS/IMKeUfzuDY8wPRsImVr6WW8lERd VLrtjmtCWfpZbAbW7ocAEVGGzqNVRw5GUuaToUyg3Bz5bks1LhT5C9AgKk461hwAqU kTg0KBEGPs8ywN+V3AZ/3WQPF/8Y2rgOc/nCGbJ8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Osipenko , Maxime Ripard , Stephen Boyd , Sasha Levin Subject: [PATCH 5.15 658/913] clk: Initialize orphan req_rate Date: Tue, 5 Apr 2022 09:28:40 +0200 Message-Id: <20220405070359.561641377@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405070339.801210740@linuxfoundation.org> References: <20220405070339.801210740@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Maxime Ripard [ Upstream commit 5f7e2af00807f2117650e711a58b7f0e986ce1df ] When registering a clock that doesn't have a recalc_rate implementation, and doesn't have its parent registered yet, we initialize the clk_core rate and 'req_rate' fields to 0. The rate field is later updated when the parent is registered in clk_core_reparent_orphans_nolock() using __clk_recalc_rates(), but the 'req_rate' field is never updated. This leads to an issue in clk_set_rate_range() and clk_put(), since those functions will call clk_set_rate() with the content of 'req_rate' to provide drivers with the opportunity to change the rate based on the new boundaries. In this case, we would call clk_set_rate() with a rate of 0, effectively enforcing the minimum allowed for this clock whenever we would call one of those two functions, even though the actual rate might be within range. Let's fix this by setting 'req_rate' in clk_core_reparent_orphans_nolock() with the rate field content just updated by the call to __clk_recalc_rates(). Fixes: 1c8e600440c7 ("clk: Add rate constraints to clocks") Reported-by: Dmitry Osipenko Tested-by: Dmitry Osipenko # T30 Nexus7 Signed-off-by: Maxime Ripard Link: https://lore.kernel.org/r/20220325161144.1901695-2-maxime@cerno.tech [sboyd@kernel.org: Reword comment] Signed-off-by: Stephen Boyd Signed-off-by: Sasha Levin --- drivers/clk/clk.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 32fd2853e8b2..5cef73a85901 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -3410,6 +3410,19 @@ static void clk_core_reparent_orphans_nolock(void) __clk_set_parent_after(orphan, parent, NULL); __clk_recalc_accuracies(orphan); __clk_recalc_rates(orphan, 0); + + /* + * __clk_init_parent() will set the initial req_rate to + * 0 if the clock doesn't have clk_ops::recalc_rate and + * is an orphan when it's registered. + * + * 'req_rate' is used by clk_set_rate_range() and + * clk_put() to trigger a clk_set_rate() call whenever + * the boundaries are modified. Let's make sure + * 'req_rate' is set to something non-zero so that + * clk_set_rate_range() doesn't drop the frequency. + */ + orphan->req_rate = orphan->rate; } } }