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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 3BCDAC47DAF for ; Thu, 18 Jan 2024 18:27:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=GJSWP0QYcGHj+sBjiF6rSFcvDZZYL2IPHUXdTULskdw=; b=BUvMEhM1CgljiE aK7DG40ANjMtg0Nm7KJZiznQeuKVPKEz++ELpilDd+QVFf6FA+Ce4oOmZFp0uCFjrWKYYWE4+E6qF mqF8yX221F3xS7w3MWDsSRtBAqrFYq44DCJyf60Xf8Ge49Uel1oQOZfK68BFyViqM9n0OflkMe435 q/Ujwdp2uhY/Ewj2W3vSUPOFsMQPTZj7HHDJDbJIftCldOb/IHZZGba7s+TelMQL/cDoH8UcizN3f 29OnPLigr5IdvmUMwNyCA5Xeyva8h9KMfUIkRHaAu5LE0MIzbFcHNa8AqswCCo6Uo981RERpfHP44 hMF49jcmHlMRK50LnLjA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rQX6p-003V8f-30; Thu, 18 Jan 2024 18:27:23 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rQX6n-003V8M-0B for linux-arm-kernel@lists.infradead.org; Thu, 18 Jan 2024 18:27:22 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 980B11042; Thu, 18 Jan 2024 10:28:02 -0800 (PST) Received: from pluto (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3C4943F766; Thu, 18 Jan 2024 10:27:15 -0800 (PST) Date: Thu, 18 Jan 2024 18:27:12 +0000 From: Cristian Marussi To: "Peng Fan (OSS)" Cc: sudeep.holla@arm.com, mturquette@baylibre.com, sboyd@kernel.org, linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, Peng Fan Subject: Re: [PATCH V3 2/2] clk: scmi: support state_ctrl_forbidden Message-ID: References: <20240115060203.813168-1-peng.fan@oss.nxp.com> <20240115060203.813168-2-peng.fan@oss.nxp.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20240115060203.813168-2-peng.fan@oss.nxp.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240118_102721_228758_077FACCC X-CRM114-Status: GOOD ( 28.23 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Jan 15, 2024 at 02:02:03PM +0800, Peng Fan (OSS) wrote: > From: Peng Fan > > Some clocks may exported to linux, while those clocks are not allowed > to configure by Linux. For example: > > SYS_CLK1----- > \ > --MUX--->MMC1_CLK > / > SYS_CLK2----- > > MMC1 needs set parent, so SYS_CLK1 and SYS_CLK2 are exported to Linux, > then the clk propagation will touch SYS_CLK1 or SYS_CLK2. > So we need bypass the failure for SYS_CLK1 or SYS_CLK2 when enable > the clock of MMC1. > Hi, so this looks good to me and apparently (as noted) the CLK framework is OK with a driver swallowing the -EACCESS when a clock is immutable, BUT at the end of the day do we even need to try this SCMI call and hide the failure in case of immutable clocks ? I mean, what if we just dont provide any callback for enable/disable...I can see plenty of drivers not providing those callbacks ? Maybe this is probably more of a question for Stephen... IOW what about doing something like below...does it make any difference in your setup ? works fine in my emulated env (Note that last snippet in clk_gate_restore_context() is probably a fix that needs to be added anyway by looking at the code in clk.c) Thanks, Cristian --->8---- diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c index 5327e0547741..a669a2f2f78b 100644 --- a/drivers/clk/clk-scmi.c +++ b/drivers/clk/clk-scmi.c @@ -121,11 +121,7 @@ static int scmi_clk_enable(struct clk_hw *hw) struct scmi_clk *clk = to_scmi_clk(hw); int ret; - ret = scmi_proto_clk_ops->enable(clk->ph, clk->id, NOT_ATOMIC); - if (ret == -EACCES && clk->info->state_ctrl_forbidden) - return 0; - - return ret; + return scmi_proto_clk_ops->enable(clk->ph, clk->id, NOT_ATOMIC); } static void scmi_clk_disable(struct clk_hw *hw) @@ -140,11 +136,7 @@ static int scmi_clk_atomic_enable(struct clk_hw *hw) struct scmi_clk *clk = to_scmi_clk(hw); int ret; - ret = scmi_proto_clk_ops->enable(clk->ph, clk->id, ATOMIC); - if (ret == -EACCES && clk->info->state_ctrl_forbidden) - return 0; - - return ret; + return scmi_proto_clk_ops->enable(clk->ph, clk->id, ATOMIC); } static void scmi_clk_atomic_disable(struct clk_hw *hw) @@ -204,6 +196,15 @@ static const struct clk_ops scmi_atomic_clk_ops = { .determine_rate = scmi_clk_determine_rate, }; +static const struct clk_ops scmi_no_state_ctrl_clk_ops = { + .recalc_rate = scmi_clk_recalc_rate, + .round_rate = scmi_clk_round_rate, + .set_rate = scmi_clk_set_rate, + .set_parent = scmi_clk_set_parent, + .get_parent = scmi_clk_get_parent, + .determine_rate = scmi_clk_determine_rate, +}; + static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk, const struct clk_ops *scmi_ops) { @@ -300,8 +301,10 @@ static int scmi_clocks_probe(struct scmi_device *sdev) * specify (or support) an enable_latency associated with a * clock, we default to use atomic operations mode. */ - if (is_atomic && - sclk->info->enable_latency <= atomic_threshold) + if (sclk->info->state_ctrl_forbidden) + scmi_ops = &scmi_no_state_ctrl_clk_ops; + else if (is_atomic && + sclk->info->enable_latency <= atomic_threshold) scmi_ops = &scmi_atomic_clk_ops; else scmi_ops = &scmi_clk_ops; diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index f0940af485a5..79b90a8099d7 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -1200,9 +1200,11 @@ void clk_gate_restore_context(struct clk_hw *hw) struct clk_core *core = hw->core; if (core->enable_count) - core->ops->enable(hw); + if (core->ops->enable) + core->ops->enable(hw); else - core->ops->disable(hw); + if (core->ops->disable) + core->ops->disable(hw); } EXPORT_SYMBOL_GPL(clk_gate_restore_context); ---8<--- > Signed-off-by: Peng Fan > --- > > V3: > Add check in atomic enable > > V2: > New. Take Cristian's suggestion > > drivers/clk/clk-scmi.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c > index 8cbe24789c24..5327e0547741 100644 > --- a/drivers/clk/clk-scmi.c > +++ b/drivers/clk/clk-scmi.c > @@ -119,8 +119,13 @@ static int scmi_clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *r > static int scmi_clk_enable(struct clk_hw *hw) > { > struct scmi_clk *clk = to_scmi_clk(hw); > + int ret; > + > + ret = scmi_proto_clk_ops->enable(clk->ph, clk->id, NOT_ATOMIC); > + if (ret == -EACCES && clk->info->state_ctrl_forbidden) > + return 0; > > - return scmi_proto_clk_ops->enable(clk->ph, clk->id, NOT_ATOMIC); > + return ret; > } > > static void scmi_clk_disable(struct clk_hw *hw) > @@ -133,8 +138,13 @@ static void scmi_clk_disable(struct clk_hw *hw) > static int scmi_clk_atomic_enable(struct clk_hw *hw) > { > struct scmi_clk *clk = to_scmi_clk(hw); > + int ret; > + > + ret = scmi_proto_clk_ops->enable(clk->ph, clk->id, ATOMIC); > + if (ret == -EACCES && clk->info->state_ctrl_forbidden) > + return 0; > > - return scmi_proto_clk_ops->enable(clk->ph, clk->id, ATOMIC); > + return ret; > } > > static void scmi_clk_atomic_disable(struct clk_hw *hw) > -- > 2.37.1 > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel