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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 4023FC4724C for ; Fri, 1 May 2020 15:26:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 25FF720708 for ; Fri, 1 May 2020 15:26:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729552AbgEAP0N (ORCPT ); Fri, 1 May 2020 11:26:13 -0400 Received: from lhrrgout.huawei.com ([185.176.76.210]:2145 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728443AbgEAP0N (ORCPT ); Fri, 1 May 2020 11:26:13 -0400 Received: from lhreml724-chm.china.huawei.com (unknown [172.18.7.108]) by Forcepoint Email with ESMTP id 0D367C3A7F7E74A2CE70; Fri, 1 May 2020 16:26:11 +0100 (IST) Received: from [127.0.0.1] (10.47.3.165) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1913.5; Fri, 1 May 2020 16:26:10 +0100 Subject: Re: [PATCH 5/5] arm/arm64: smccc: Add ARCH_SOC_ID support To: Sudeep Holla , "linux-arm-kernel@lists.infradead.org" CC: Mark Rutland , Lorenzo Pieralisi , Catalin Marinas , "linux-kernel@vger.kernel.org" , Steven Price , "harb@amperecomputing.com" , Will Deacon References: <20200430114814.14116-1-sudeep.holla@arm.com> <20200430114814.14116-6-sudeep.holla@arm.com> From: John Garry Message-ID: <426ff8ab-9c13-4301-a91e-989c19c4ff58@huawei.com> Date: Fri, 1 May 2020 16:25:27 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.1.2 MIME-Version: 1.0 In-Reply-To: <20200430114814.14116-6-sudeep.holla@arm.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.47.3.165] X-ClientProxiedBy: lhreml727-chm.china.huawei.com (10.201.108.78) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30/04/2020 12:48, Sudeep Holla wrote: > +static int __init smccc_soc_init(void) > +{ > + struct device *dev; > + int ret, soc_id_rev; > + struct arm_smccc_res res; > + static char soc_id_str[8], soc_id_rev_str[12]; > + > + if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2) > + return 0; > + > + ret = smccc_soc_id_support_check(); > + if (ret) > + return ret; > + > + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_SOC_ID, 0, &res); > + > + ret = smccc_map_error_codes(res.a0); > + if (ret) > + return ret; > + > + soc_id_version = res.a0; > + > + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_SOC_ID, 1, &res); > + > + ret = smccc_map_error_codes(res.a0); > + if (ret) > + return ret; > + > + soc_id_rev = res.a0; > + > + soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL); > + if (!soc_dev_attr) > + return -ENOMEM; > + > + sprintf(soc_id_str, "0x%04x", IMP_DEF_SOC_ID(soc_id_version)); > + sprintf(soc_id_rev_str, "0x%08x", soc_id_rev); > + > + soc_dev_attr->soc_id = soc_id_str; > + soc_dev_attr->revision = soc_id_rev_str; > + > + soc_dev = soc_device_register(soc_dev_attr); > + if (IS_ERR(soc_dev)) { > + ret = PTR_ERR(soc_dev); > + goto free_soc; > + } > + > + dev = soc_device_to_device(soc_dev); > + Just wondering, what about if the platform already had a SoC driver - now it could have another one, such that we may have multiple sysfs soc devices, right? Thanks, John > + ret = devm_device_add_groups(dev, jep106_id_groups); > + if (ret) { > + dev_err(dev, "sysfs create failed: %d\n", ret); > + goto unregister_soc; > + } > + > + pr_info("SMCCC SoC ID: %s Revision %s\n", soc_dev_attr->soc_id, > + soc_dev_attr->revision); > + > + return 0;