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=-4.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 E9036C43381 for ; Fri, 22 Feb 2019 19:08:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B461520700 for ; Fri, 22 Feb 2019 19:08:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550862493; bh=zn5gREfnAEgVz2BI4KrdGye4NvLUosAjzJ0G//JMftY=; h=Subject:References:From:In-Reply-To:To:Cc:Date:List-ID:From; b=x7XrL95im5ZTIBMxhcQu+ykVoEl988ZDYh7lDiYhf6JEfS0ygejREv6Mk1aCjFR5A f77WhVvzX+FVv426mx9I7EaMHwt4HImw69mwPnbvwl25RPx+EWdKulVyqqf/c/tI5e K5iQ7To4bMA9ElR/DRWRyeF2g2evO4rV1PgfFuD4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726346AbfBVTIM (ORCPT ); Fri, 22 Feb 2019 14:08:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:50606 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725937AbfBVTIL (ORCPT ); Fri, 22 Feb 2019 14:08:11 -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 D23B3206BB; Fri, 22 Feb 2019 19:08:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550862490; bh=zn5gREfnAEgVz2BI4KrdGye4NvLUosAjzJ0G//JMftY=; h=Subject:References:From:In-Reply-To:To:Cc:Date:From; b=rvJ71P0vQdSAFNlEJjZ4Pe8azzNtfsV9AtdZmcTkrOuZxK9geLTwKtG7YAf3l8Vwm qWX1lnThkUN9xUae0vOKy2p3arrmCbUPxQZo2AWLVfKPqH/orPjaPlLAAxHIC359l6 YxCnzqmv8kafRdWDmgPjp8LHeKyvH7XdIBIXTvIQ= Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH RESEND V6 2/2] clk: imx: scu: add cpu frequency scaling support Message-ID: <155086249004.77512.8709011386763447047@swboyd.mtv.corp.google.com> User-Agent: alot/0.8 References: <1550802436-13007-1-git-send-email-Anson.Huang@nxp.com> <1550802436-13007-2-git-send-email-Anson.Huang@nxp.com> From: Stephen Boyd In-Reply-To: <1550802436-13007-2-git-send-email-Anson.Huang@nxp.com> To: "devicetree@vger.kernel.org" , "festevam@gmail.com" , "kernel@pengutronix.de" , "linux-arm-kernel@lists.infradead.org" , "linux-clk@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "mark.rutland@arm.com" , "mturquette@baylibre.com" , "robh+dt@kernel.org" , "s.hauer@pengutronix.de" , "shawnguo@kernel.org" , Aisheng Dong , Anson Huang , Daniel Baluta Cc: dl-linux-imx Date: Fri, 22 Feb 2019 11:08:10 -0800 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Quoting Anson Huang (2019-02-21 18:32:10) > On NXP's i.MX SoCs with system controller inside, CPU frequency > scaling can ONLY be done by system controller firmware, and it > can ONLY be requested from secure mode, so Linux kernel has to > call ARM SMC to trap to ARM-Trusted-Firmware to request system > controller firmware to do CPU frequency scaling. >=20 > This patch adds i.MX system controller CPU frequency scaling support, > it reuses cpufreq-dt driver and implement the CPU frequency scaling > inside SCU clock driver. >=20 > Signed-off-by: Anson Huang Ah I missed one thing, see below. > @@ -180,6 +185,23 @@ static long clk_scu_round_rate(struct clk_hw *hw, un= signed long rate, > return rate; > } > =20 > +static int clk_scu_atf_set_cpu_rate(struct clk_hw *hw, unsigned long rat= e, > + unsigned long parent_rate) > +{ > + struct clk_scu *clk =3D to_clk_scu(hw); > + struct arm_smccc_res res; > + unsigned long cluster_id; > + > + if (clk->rsrc_id =3D=3D IMX_SC_R_A35) > + cluster_id =3D 0; Do we still need to check this anymore? Why not just always use cluster_id 0? > + > + /* CPU frequency scaling can ONLY be done by ARM-Trusted-Firmware= */ > + arm_smccc_smc(IMX_SIP_CPUFREQ, IMX_SIP_SET_CPUFREQ, > + cluster_id, rate, 0, 0, 0, 0, &res); Because not checking would make this work, vs. checking causes this code to sometimes use an uninitialized value from the stack. > + > + return 0; > +} > + From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Boyd Subject: Re: [PATCH RESEND V6 2/2] clk: imx: scu: add cpu frequency scaling support Date: Fri, 22 Feb 2019 11:08:10 -0800 Message-ID: <155086249004.77512.8709011386763447047@swboyd.mtv.corp.google.com> References: <1550802436-13007-1-git-send-email-Anson.Huang@nxp.com> <1550802436-13007-2-git-send-email-Anson.Huang@nxp.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <1550802436-13007-2-git-send-email-Anson.Huang@nxp.com> Sender: linux-kernel-owner@vger.kernel.org To: "devicetree@vger.kernel.org" , "festevam@gmail.com" , "kernel@pengutronix.de" , "linux-arm-kernel@lists.infradead.org" , "linux-clk@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "mark.rutland@arm.com" , "mturquette@baylibre.com" , "robh+dt@kernel.org" , "s.hauer@pengutronix.de" , "shawnguo@kernel.org" , Aisheng Dong , Anson Huang , Daniel Baluta Cc: dl-linux-imx List-Id: devicetree@vger.kernel.org Quoting Anson Huang (2019-02-21 18:32:10) > On NXP's i.MX SoCs with system controller inside, CPU frequency > scaling can ONLY be done by system controller firmware, and it > can ONLY be requested from secure mode, so Linux kernel has to > call ARM SMC to trap to ARM-Trusted-Firmware to request system > controller firmware to do CPU frequency scaling. >=20 > This patch adds i.MX system controller CPU frequency scaling support, > it reuses cpufreq-dt driver and implement the CPU frequency scaling > inside SCU clock driver. >=20 > Signed-off-by: Anson Huang Ah I missed one thing, see below. > @@ -180,6 +185,23 @@ static long clk_scu_round_rate(struct clk_hw *hw, un= signed long rate, > return rate; > } > =20 > +static int clk_scu_atf_set_cpu_rate(struct clk_hw *hw, unsigned long rat= e, > + unsigned long parent_rate) > +{ > + struct clk_scu *clk =3D to_clk_scu(hw); > + struct arm_smccc_res res; > + unsigned long cluster_id; > + > + if (clk->rsrc_id =3D=3D IMX_SC_R_A35) > + cluster_id =3D 0; Do we still need to check this anymore? Why not just always use cluster_id 0? > + > + /* CPU frequency scaling can ONLY be done by ARM-Trusted-Firmware= */ > + arm_smccc_smc(IMX_SIP_CPUFREQ, IMX_SIP_SET_CPUFREQ, > + cluster_id, rate, 0, 0, 0, 0, &res); Because not checking would make this work, vs. checking causes this code to sometimes use an uninitialized value from the stack. > + > + return 0; > +} > + 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=-4.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 2251DC43381 for ; Fri, 22 Feb 2019 19:08:21 +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 E58CC206BB for ; Fri, 22 Feb 2019 19:08:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="eJ1S7HSd"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="rvJ71P0v" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E58CC206BB 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-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:Date:To:In-Reply-To:From:References: Message-ID:Subject:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=K4tRsZ62GGEGSQE/bwY6HihVhChhEKxLRqgS+xtNJfo=; b=eJ1S7HSdh18Ucx 88RK+FRck9wsPVF/sIegseHE+n3CJHxhdLL0w/snVMQYuvhEbFYYW50/D6c4Cj3THaOJOrGlZPQbm EfhfP3bws0bb6GoaP38x+pHRekO3Q9/jhE0EYGzDk0Sn82nSQb5CUDLMAosl827WnyA9vQCTAYEA1 331Jb6MvwpiDD1wU3b8psUXNQuuuVwfyWqO7y+ZYeoor9AHvxMfZ4M/dPjHbgjjoK0+ptlDhb4vyr r1uKUPoEO4NQKONKEDoiQohMD8qb8ngKVzkhEJSv+5gMsnCsD+jF3xwBIVJ7OtwHpqFNZbOhBBwpg jd6psUmdZDzwG8tJJCJw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gxGBF-0001mb-7w; Fri, 22 Feb 2019 19:08:17 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gxGB9-0001lm-A0 for linux-arm-kernel@lists.infradead.org; Fri, 22 Feb 2019 19:08:12 +0000 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 D23B3206BB; Fri, 22 Feb 2019 19:08:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550862490; bh=zn5gREfnAEgVz2BI4KrdGye4NvLUosAjzJ0G//JMftY=; h=Subject:References:From:In-Reply-To:To:Cc:Date:From; b=rvJ71P0vQdSAFNlEJjZ4Pe8azzNtfsV9AtdZmcTkrOuZxK9geLTwKtG7YAf3l8Vwm qWX1lnThkUN9xUae0vOKy2p3arrmCbUPxQZo2AWLVfKPqH/orPjaPlLAAxHIC359l6 YxCnzqmv8kafRdWDmgPjp8LHeKyvH7XdIBIXTvIQ= MIME-Version: 1.0 Subject: Re: [PATCH RESEND V6 2/2] clk: imx: scu: add cpu frequency scaling support Message-ID: <155086249004.77512.8709011386763447047@swboyd.mtv.corp.google.com> User-Agent: alot/0.8 References: <1550802436-13007-1-git-send-email-Anson.Huang@nxp.com> <1550802436-13007-2-git-send-email-Anson.Huang@nxp.com> From: Stephen Boyd In-Reply-To: <1550802436-13007-2-git-send-email-Anson.Huang@nxp.com> To: "devicetree@vger.kernel.org" , "festevam@gmail.com" , "kernel@pengutronix.de" , "linux-arm-kernel@lists.infradead.org" , "linux-clk@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "mark.rutland@arm.com" , "mturquette@baylibre.com" , "robh+dt@kernel.org" , "s.hauer@pengutronix.de" , "shawnguo@kernel.org" , Aisheng Dong , Anson Huang , Daniel Baluta Date: Fri, 22 Feb 2019 11:08:10 -0800 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190222_110811_367382_2AD7D944 X-CRM114-Status: GOOD ( 12.49 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: dl-linux-imx 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 Quoting Anson Huang (2019-02-21 18:32:10) > On NXP's i.MX SoCs with system controller inside, CPU frequency > scaling can ONLY be done by system controller firmware, and it > can ONLY be requested from secure mode, so Linux kernel has to > call ARM SMC to trap to ARM-Trusted-Firmware to request system > controller firmware to do CPU frequency scaling. > > This patch adds i.MX system controller CPU frequency scaling support, > it reuses cpufreq-dt driver and implement the CPU frequency scaling > inside SCU clock driver. > > Signed-off-by: Anson Huang Ah I missed one thing, see below. > @@ -180,6 +185,23 @@ static long clk_scu_round_rate(struct clk_hw *hw, unsigned long rate, > return rate; > } > > +static int clk_scu_atf_set_cpu_rate(struct clk_hw *hw, unsigned long rate, > + unsigned long parent_rate) > +{ > + struct clk_scu *clk = to_clk_scu(hw); > + struct arm_smccc_res res; > + unsigned long cluster_id; > + > + if (clk->rsrc_id == IMX_SC_R_A35) > + cluster_id = 0; Do we still need to check this anymore? Why not just always use cluster_id 0? > + > + /* CPU frequency scaling can ONLY be done by ARM-Trusted-Firmware */ > + arm_smccc_smc(IMX_SIP_CPUFREQ, IMX_SIP_SET_CPUFREQ, > + cluster_id, rate, 0, 0, 0, 0, &res); Because not checking would make this work, vs. checking causes this code to sometimes use an uninitialized value from the stack. > + > + return 0; > +} > + _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel