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 AEC8DC4332F for ; Tue, 31 Oct 2023 13:36:24 +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=tSsYjLoKuQDU7ct3NrfCKa+l+1PRnuia4ygEpqRcw7s=; b=DA9mZlW26aZJCs jMM7bY2C2qzfHqqry+EKNZxu67anaxXuTsylGSOaUdNGCAZP3MhoaAR8F02ISwhQTGofKqOvt2KX0 bvt13RwTQj1mWavrmakDfOeCjKcm9rbVczAxdG8hpkTGGVY5HOxZIAFXmt2DM1IUd8fDkfQMUXllo xRvmUILlj2yXh5dvk4fFPgQW8S5AotkVcqgmc4Aw36RIu+w9po59iNxZlqy142i5qarB3DywmNacE ZAm260mRAB8VCpVNxP65zvYWdDT/EWY9768hXZACN/GcX2sMuz97i5OPxFAMVHEiaSieRdz1vurVV 8iFfOdqpONUuqPO/94jg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qxouS-005Lsc-1k; Tue, 31 Oct 2023 13:35:56 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qxouP-005Ls1-1d for linux-arm-kernel@lists.infradead.org; Tue, 31 Oct 2023 13:35:55 +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 56924C15; Tue, 31 Oct 2023 06:36:29 -0700 (PDT) Received: from pluto (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2DD423F738; Tue, 31 Oct 2023 06:35:46 -0700 (PDT) Date: Tue, 31 Oct 2023 13:35:44 +0000 From: Cristian Marussi To: Peng Fan Cc: "Peng Fan (OSS)" , "sudeep.holla@arm.com" , "linux-arm-kernel@lists.infradead.org" , "linux-clk@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Ranjani Vaidyanathan , Glen G Wienecke , "nitin.garg@nxp.com" , Chuck Cannon , "Souvik.Chakravarty@arm.com" Subject: Re: [PATCH V1] firmware: arm_scmi: clock: support clock denied flags Message-ID: References: <20231031122734.1371524-1-peng.fan@oss.nxp.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231031_063553_637340_2B4FC9B1 X-CRM114-Status: GOOD ( 29.52 ) 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 Tue, Oct 31, 2023 at 01:33:17PM +0000, Peng Fan wrote: > > Subject: Re: [PATCH V1] firmware: arm_scmi: clock: support clock denied > > flags > > > > On Tue, Oct 31, 2023 at 08:27:34PM +0800, Peng Fan (OSS) wrote: > > > From: Peng Fan > > > > > > The firmware may export flags to indicate whether the clock is allowed > > > to set rate, set parent, enable/disable from the Agent. > > > > > > If Agent is not allowed to enable/disable, directly return success. > > > > ... even though, this success on deny built-in policy could be > > controversial.. > Yeah. > > .Have you tried the different approach of not registerig the > > enable/prepare callbacks in clk-scmi instead ? > > Not yet, I could give a look. But not have much time > in the following week. > > > > From the Clk framework code it seems could be handled gracefully. > > (I have not tried though...) > > If there is no enable/disable/prepare/unprepared hooks, the enable > counter or prepare counter would be used. > Yes this is what I could understand. Thanks, Cristian > Thanks, > Peng. > > > > Thanks, > > Cristian > > > > > If Agent is not allowed to set rate/parent, directly return -EACCES to > > > avoid SCMI RPC calls. > > > > > > Signed-off-by: Peng Fan > > > --- > > > > > > V1: > > > drop the changes in clock.c, add an attribute entry in clock info > > > which may be easy for extending new flag. > > > > > > SPEC still not have such support, this is for discussion > > > > > > drivers/firmware/arm_scmi/clock.c | 19 +++++++++++++++++++ > > > include/linux/scmi_protocol.h | 1 + > > > 2 files changed, 20 insertions(+) > > > > > > diff --git a/drivers/firmware/arm_scmi/clock.c > > > b/drivers/firmware/arm_scmi/clock.c > > > index 42b81c181d68..fad4329a21fc 100644 > > > --- a/drivers/firmware/arm_scmi/clock.c > > > +++ b/drivers/firmware/arm_scmi/clock.c > > > @@ -46,6 +46,9 @@ struct scmi_msg_resp_clock_attributes { > > > #define SUPPORTS_RATE_CHANGE_REQUESTED_NOTIF(x) ((x) & > > BIT(30)) > > > #define SUPPORTS_EXTENDED_NAMES(x) ((x) & BIT(29)) > > > #define SUPPORTS_PARENT_CLOCK(x) ((x) & BIT(28)) > > > +#define SCMI_CLOCK_SET_ENABLE_DENIED BIT(15) > > > +#define SCMI_CLOCK_SET_RATE_DENIED BIT(14) > > > +#define SCMI_CLOCK_SET_PARENT_DENIED BIT(13) > > > u8 name[SCMI_SHORT_NAME_MAX_SIZE]; > > > __le32 clock_enable_latency; > > > }; > > > @@ -307,6 +310,7 @@ static int scmi_clock_attributes_get(const struct > > scmi_protocol_handle *ph, > > > if (PROTOCOL_REV_MAJOR(version) >= 0x2) > > > latency = le32_to_cpu(attr->clock_enable_latency); > > > clk->enable_latency = latency ? : U32_MAX; > > > + clk->attributes = attributes; > > > } > > > > > > ph->xops->xfer_put(ph, t); > > > @@ -499,6 +503,10 @@ static int scmi_clock_rate_set(const struct > > scmi_protocol_handle *ph, > > > struct scmi_xfer *t; > > > struct scmi_clock_set_rate *cfg; > > > struct clock_info *ci = ph->get_priv(ph); > > > + struct scmi_clock_info *clk = ci->clk + clk_id; > > > + > > > + if (clk->attributes & SCMI_CLOCK_SET_RATE_DENIED) > > > + return -EACCES; > > > > > > ret = ph->xops->xfer_get_init(ph, CLOCK_RATE_SET, sizeof(*cfg), 0, > > &t); > > > if (ret) > > > @@ -585,6 +593,9 @@ scmi_clock_set_parent(const struct > > scmi_protocol_handle *ph, u32 clk_id, > > > if (parent_id >= clk->num_parents) > > > return -EINVAL; > > > > > > + if (clk->attributes & SCMI_CLOCK_SET_PARENT_DENIED) > > > + return -EACCES; > > > + > > > ret = ph->xops->xfer_get_init(ph, CLOCK_PARENT_SET, > > > sizeof(*cfg), 0, &t); > > > if (ret) > > > @@ -668,6 +679,10 @@ static int scmi_clock_enable(const struct > > scmi_protocol_handle *ph, u32 clk_id, > > > bool atomic) > > > { > > > struct clock_info *ci = ph->get_priv(ph); > > > + struct scmi_clock_info *clk = ci->clk + clk_id; > > > + > > > + if (clk->attributes & SCMI_CLOCK_SET_ENABLE_DENIED) > > > + return 0; > > > > > > return ci->clock_config_set(ph, clk_id, CLK_STATE_ENABLE, > > > NULL_OEM_TYPE, 0, atomic); > > > @@ -677,6 +692,10 @@ static int scmi_clock_disable(const struct > > scmi_protocol_handle *ph, u32 clk_id, > > > bool atomic) > > > { > > > struct clock_info *ci = ph->get_priv(ph); > > > + struct scmi_clock_info *clk = ci->clk + clk_id; > > > + > > > + if (clk->attributes & SCMI_CLOCK_SET_ENABLE_DENIED) > > > + return 0; > > > > > > return ci->clock_config_set(ph, clk_id, CLK_STATE_DISABLE, > > > NULL_OEM_TYPE, 0, atomic); > > > diff --git a/include/linux/scmi_protocol.h > > > b/include/linux/scmi_protocol.h index f2f05fb42d28..ddf5363c8cfd > > > 100644 > > > --- a/include/linux/scmi_protocol.h > > > +++ b/include/linux/scmi_protocol.h > > > @@ -58,6 +58,7 @@ struct scmi_clock_info { > > > u64 step_size; > > > } range; > > > }; > > > + u32 attributes; > > > int num_parents; > > > u32 *parents; > > > }; > > > -- > > > 2.37.1 > > > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel