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 5E1D1C54E4A for ; Wed, 28 Feb 2024 17:18:34 +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=H2UbaI0Lqa5KGpmggL177/vLbJfns0K+hFIsFRBt5Nc=; b=oTslOIhF0haWVx Uo93rMJB9w+IgvXd8aSITBnkmjhdnvA54p5IwAz6A+uq3+rB0wm/DMQQXgYHojyKnxvq///8LPREF 9kpbSjYCVb3tOZRsRQ/2VLICno60WBQN2NCZ8o1k112F6VAO0VLHTJl80+ofg7gzLLIUw98u6Khkk ZfrHOLa0/Bi0keqB9M8RyjvG50H0xU7zUKRgXwqDvGvuMjdSUNj2sqeQ7AnjeZe/4E3Z8VhLeItMA lAfrTfoblV1neoEneyt7tUxPtVTiIlEHtDuEWnx2Xe7XCL7OFRvQtqJh8W2X9jw2q4ResShjkHXD/ 5+ZlqsZRJ+ZGATY4mIqw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rfNZY-0000000AGIS-25FC; Wed, 28 Feb 2024 17:18:24 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rfNZT-0000000AGHd-3y8N for linux-arm-kernel@lists.infradead.org; Wed, 28 Feb 2024 17:18:21 +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 0208EC15; Wed, 28 Feb 2024 09:18:58 -0800 (PST) Received: from pluto (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E3A8E3F762; Wed, 28 Feb 2024 09:18:15 -0800 (PST) Date: Wed, 28 Feb 2024 17:18:13 +0000 From: Cristian Marussi To: Sibi Sankar Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, sudeep.holla@arm.com, james.quinlan@broadcom.com, f.fainelli@gmail.com, vincent.guittot@linaro.org, peng.fan@oss.nxp.com, michal.simek@amd.com, quic_nkela@quicinc.com, souvik.chakravarty@arm.com Subject: Re: [PATCH] firmware: arm_scmi: Add support for multiple vendors custom protocols Message-ID: References: <20240221220426.1205146-1-cristian.marussi@arm.com> <4fa47411-225d-e8cd-c5c7-79ac2de2f52d@quicinc.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <4fa47411-225d-e8cd-c5c7-79ac2de2f52d@quicinc.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240228_091820_122738_100549C2 X-CRM114-Status: GOOD ( 42.89 ) 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 Wed, Feb 28, 2024 at 10:36:43PM +0530, Sibi Sankar wrote: > > > On 2/22/24 03:34, Cristian Marussi wrote: > > Add a mechanism to be able to tag vendor protocol modules at compile-time > > with a vendor/sub_vendor string and an implementation version and then to > > choose to load, at run-time, only those vendor protocol modules matching > > as close as possible the vendor/subvendor identification advertised by > > the SCMI platform server. > > > > In this way, any in-tree existent vendor protocol module can be build and > > shipped by default in a single kernel image, even when using the same > > clashing protocol identification numbers, since the SCMI core will take > > care at run-time to load only the ones pertinent to the running system. > > > > Signed-off-by: Cristian Marussi > > Cristian, > > Thanks for the patch. > > > > --- > > Hi all, > > > > this is meant to address the possibility of having multiple vendors > > implementing distinct SCMI vendor protocols with possibly the same > > overlapping protocol number without the need of crafting the Kconfig > > at compile time to include only wanted protos > > (and without the need for a lottery :P) > > > > Basic idea is simple: > > > > - vendor protos HAS to be 'tagged' at build time with a vendor_id > > - vendor protos COULD also optionally be tagged at build time with > > sub_vendor_id and implemetation version > > > > - at init all the build vendor protos are registerd with the SCMI core > > using a key derived from the above tags > > > > - at SCMI probe time the platform is identified via Base protocol as > > usual and all the required vendor protos (i.e. IDs defined in the DT > > as usual) are loaded after a lookup process based on the following rules: > > > > + protocol DB is searched using the platform/Base runtime provided tags > > > > / / > > > > using the the following search logic (keys), first match: > > > > 1. proto_id / / / > > > > 2. proto_id / / / 0 > > > > 3. proto_id / / NULL / 0 > > > > IOW, closest match, depending on how much fine grained is your > > protocol tuned (tagged) for the platform. > > > > I am doubtful about the usage of , and tempted to drop it > > since we have anyway protocol version and NEGOTIATE_PROTOCOL_VERSION > > to deal with slight difference in fw revision... > > > > Based on sudeep/for-linux-next on top of > > > > 1c2c88cfcb2b ("clk: scmi: Support get/set duty_cycle operations") > > > > Minimally tested .... > > > > Any feedback welcome > > > > Thanks, > > Cristian > > --- > > drivers/firmware/arm_scmi/driver.c | 166 ++++++++++++++++++++++---- > > drivers/firmware/arm_scmi/protocols.h | 5 + > > 2 files changed, 149 insertions(+), 22 deletions(-) > > > > diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c > > index 34d77802c990..8fb2903698c9 100644 > > --- a/drivers/firmware/arm_scmi/driver.c > > +++ b/drivers/firmware/arm_scmi/driver.c > > @@ -33,6 +33,7 @@ > > #include > > #include > > #include > > +#include > > #include "common.h" > > #include "notify.h" > > @@ -44,8 +45,7 @@ > > static DEFINE_IDA(scmi_id); > > -static DEFINE_IDR(scmi_protocols); > > -static DEFINE_SPINLOCK(protocol_lock); > > +static DEFINE_XARRAY(scmi_protocols); > > /* List of all SCMI devices active in system */ > > static LIST_HEAD(scmi_list); > > @@ -194,11 +194,90 @@ struct scmi_info { > > #define bus_nb_to_scmi_info(nb) container_of(nb, struct scmi_info, bus_nb) > > #define req_nb_to_scmi_info(nb) container_of(nb, struct scmi_info, dev_req_nb) > > -static const struct scmi_protocol *scmi_protocol_get(int protocol_id) > > +static unsigned long > > +scmi_vendor_protocol_signature(unsigned protocol_id, char *vendor_id, > > + char *sub_vendor_id, u32 impl_ver) > > { > > - const struct scmi_protocol *proto; > > + char *signature, *p; > > + unsigned long hash = 0; > > - proto = idr_find(&scmi_protocols, protocol_id); > > + /* vendor_id/sub_vendor_id guaranteed <= SCMI_SHORT_NAME_MAX_SIZE */ > > + signature = kasprintf(GFP_KERNEL, "%02X|%s|%s|0x%08X", protocol_id, > > + vendor_id ?: "", sub_vendor_id ?: "", impl_ver); > > + if (!signature) > > + return 0; > > + > > + p = signature; > > + while (*p) > > + hash = partial_name_hash(tolower(*p++), hash); > > + hash = end_name_hash(hash); > > + > > + kfree(signature); > > + > > + return hash; > > +} > > + > > +static unsigned long > > +scmi_protocol_key_calculate(int protocol_id, char *vendor_id, > > + char *sub_vendor_id, u32 impl_ver) > > +{ > > + if (protocol_id < SCMI_PROTOCOL_VENDOR) > > + return protocol_id; > > + else > > + return scmi_vendor_protocol_signature(protocol_id, vendor_id, > > + sub_vendor_id, impl_ver); > > +} > > + > > +static const struct scmi_protocol * > > +scmi_vendor_protocol_lookup(int protocol_id, char *vendor_id, > > + char *sub_vendor_id, u32 impl_ver) > > +{ > > + unsigned long key; > > + struct scmi_protocol *proto = NULL; > > + > > + /* Searching for closest match ...*/ > > + key = scmi_protocol_key_calculate(protocol_id, vendor_id, > > + sub_vendor_id, impl_ver); > > + if (key) > > + proto = xa_load(&scmi_protocols, key); > > + > > + if (proto) > > + return proto; > > + > > + /* Any match on vendor/sub_vendor ? */ > > + if (impl_ver) { > > + key = scmi_protocol_key_calculate(protocol_id, vendor_id, > > + sub_vendor_id, 0); > > + if (key) > > + proto = xa_load(&scmi_protocols, key); > > + > > + if (proto) > > + return proto; > > + } > > + > > + /* Any match on just the vendor ? */ > > + if (sub_vendor_id) { > > + key = scmi_protocol_key_calculate(protocol_id, vendor_id, > > + NULL, 0); > > + if (key) > > + proto = xa_load(&scmi_protocols, key); > > + } > > + > > + return proto; > > +} > > + > > +static const struct scmi_protocol * > > +scmi_protocol_get(int protocol_id, struct scmi_revision_info *version) > > +{ > > + const struct scmi_protocol *proto = NULL; > > + > > + if (protocol_id < SCMI_PROTOCOL_VENDOR) > > + proto = xa_load(&scmi_protocols, protocol_id); > > + else > > + proto = scmi_vendor_protocol_lookup(protocol_id, > > + version->vendor_id, > > + version->sub_vendor_id, > > + version->impl_ver); > > if (!proto || !try_module_get(proto->owner)) { > > pr_warn("SCMI Protocol 0x%x not found!\n", protocol_id); > > return NULL; > > @@ -206,21 +285,47 @@ static const struct scmi_protocol *scmi_protocol_get(int protocol_id) > > pr_debug("Found SCMI Protocol 0x%x\n", protocol_id); > > + if (protocol_id >= SCMI_PROTOCOL_VENDOR) > > + pr_info("Loaded SCMI Vendor Protocol 0x%x - %s %s %X\n", > > + protocol_id, proto->vendor_id ?: "", > > + proto->sub_vendor_id ?: "", proto->impl_ver); > > + > > return proto; > > } > > -static void scmi_protocol_put(int protocol_id) > > +static void scmi_protocol_put(const struct scmi_protocol *proto) > > { > > - const struct scmi_protocol *proto; > > - > > - proto = idr_find(&scmi_protocols, protocol_id); > > if (proto) > > module_put(proto->owner); > > } > > +static int scmi_vendor_protocol_check(const struct scmi_protocol *proto) > > +{ > > + if (!proto->vendor_id) { > > + pr_err("missing vendor_id for protocol 0x%x\n", proto->id); > > + return -EINVAL; > > + } > > + > > + if (proto->vendor_id && > > You can drop ^^, since you've already checked for it. > Ah, right it's just up there :P > Reviewed-and-Tested-by: Sibi Sankar > Thanks for the review, I will wait for more possible feedback and reviews before reposting a V2 with this fix. Thanks, Cristian _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel