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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 C9BAEC433B4 for ; Thu, 15 Apr 2021 06:36:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 98B0D610E6 for ; Thu, 15 Apr 2021 06:36:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230214AbhDOGgq (ORCPT ); Thu, 15 Apr 2021 02:36:46 -0400 Received: from mga05.intel.com ([192.55.52.43]:58244 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229503AbhDOGgp (ORCPT ); Thu, 15 Apr 2021 02:36:45 -0400 IronPort-SDR: Kg4+8JsQjks/NkYHpOvV9GyuDrwgAbEf2Ns/v+qOS0Oc1lIJPxuZryUJ89ny14JMfXV/Bus4AP w/hy+B5V3RtQ== X-IronPort-AV: E=McAfee;i="6200,9189,9954"; a="280110298" X-IronPort-AV: E=Sophos;i="5.82,223,1613462400"; d="scan'208";a="280110298" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Apr 2021 23:36:22 -0700 IronPort-SDR: cUCFkyBP4F1zQegbRNZjRuBuYb5nTtdKHouuUdwf2fWvM3jzUJyz9Cj13j5a0BE66KmUWrq6s2 +sqekD9u+NdQ== X-IronPort-AV: E=Sophos;i="5.82,223,1613462400"; d="scan'208";a="418634557" Received: from lingshan-mobl5.ccr.corp.intel.com (HELO [10.254.209.173]) ([10.254.209.173]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Apr 2021 23:36:19 -0700 Subject: Re: [PATCH 1/3] vDPA/ifcvf: deduce VIRTIO device ID when probe To: Jason Wang , Zhu Lingshan , mst@redhat.com, lulu@redhat.com, leonro@nvidia.com Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org References: <20210414091832.5132-1-lingshan.zhu@intel.com> <20210414091832.5132-2-lingshan.zhu@intel.com> <85483ff1-cf98-ad05-0c53-74caa2464459@redhat.com> From: Zhu Lingshan Message-ID: <92ef6264-4462-cbd4-5db8-6ce6b68762e0@linux.intel.com> Date: Thu, 15 Apr 2021 14:36:15 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.9.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 4/15/2021 2:30 PM, Jason Wang wrote: > > 在 2021/4/15 下午1:52, Zhu Lingshan 写道: >> >> >> On 4/15/2021 11:30 AM, Jason Wang wrote: >>> >>> 在 2021/4/14 下午5:18, Zhu Lingshan 写道: >>>> This commit deduces VIRTIO device ID as device type when probe, >>>> then ifcvf_vdpa_get_device_id() can simply return the ID. >>>> ifcvf_vdpa_get_features() and ifcvf_vdpa_get_config_size() >>>> can work properly based on the device ID. >>>> >>>> Signed-off-by: Zhu Lingshan >>>> --- >>>>   drivers/vdpa/ifcvf/ifcvf_base.h |  1 + >>>>   drivers/vdpa/ifcvf/ifcvf_main.c | 22 ++++++++++------------ >>>>   2 files changed, 11 insertions(+), 12 deletions(-) >>>> >>>> diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h >>>> b/drivers/vdpa/ifcvf/ifcvf_base.h >>>> index b2eeb16b9c2c..1c04cd256fa7 100644 >>>> --- a/drivers/vdpa/ifcvf/ifcvf_base.h >>>> +++ b/drivers/vdpa/ifcvf/ifcvf_base.h >>>> @@ -84,6 +84,7 @@ struct ifcvf_hw { >>>>       u32 notify_off_multiplier; >>>>       u64 req_features; >>>>       u64 hw_features; >>>> +    u32 dev_type; >>>>       struct virtio_pci_common_cfg __iomem *common_cfg; >>>>       void __iomem *net_cfg; >>>>       struct vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2]; >>>> diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c >>>> b/drivers/vdpa/ifcvf/ifcvf_main.c >>>> index 44d7586019da..99b0a6b4c227 100644 >>>> --- a/drivers/vdpa/ifcvf/ifcvf_main.c >>>> +++ b/drivers/vdpa/ifcvf/ifcvf_main.c >>>> @@ -323,19 +323,9 @@ static u32 ifcvf_vdpa_get_generation(struct >>>> vdpa_device *vdpa_dev) >>>>     static u32 ifcvf_vdpa_get_device_id(struct vdpa_device *vdpa_dev) >>>>   { >>>> -    struct ifcvf_adapter *adapter = vdpa_to_adapter(vdpa_dev); >>>> -    struct pci_dev *pdev = adapter->pdev; >>>> -    u32 ret = -ENODEV; >>>> - >>>> -    if (pdev->device < 0x1000 || pdev->device > 0x107f) >>>> -        return ret; >>>> - >>>> -    if (pdev->device < 0x1040) >>>> -        ret =  pdev->subsystem_device; >>>> -    else >>>> -        ret =  pdev->device -0x1040; >>>> +    struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev); >>>>   -    return ret; >>>> +    return vf->dev_type; >>>>   } >>>>     static u32 ifcvf_vdpa_get_vendor_id(struct vdpa_device *vdpa_dev) >>>> @@ -466,6 +456,14 @@ static int ifcvf_probe(struct pci_dev *pdev, >>>> const struct pci_device_id *id) >>>>       pci_set_drvdata(pdev, adapter); >>>>         vf = &adapter->vf; >>>> +    if (pdev->device < 0x1000 || pdev->device > 0x107f) >>>> +        return -EOPNOTSUPP; >>>> + >>>> +    if (pdev->device < 0x1040) >>>> +        vf->dev_type =  pdev->subsystem_device; >>>> +    else >>>> +        vf->dev_type =  pdev->device - 0x1040; >>> >>> >>> So a question here, is the device a transtional device or modern one? >>> >>> If it's a transitonal one, can it swtich endianess automatically or >>> not? >>> >>> Thanks >> Hi Jason, >> >> This driver should drive both modern and transitional devices as we >> discussed before. >> If it's a transitional one, it will act as a modern device by >> default, legacy mode is a fail-over path. > > > Note that legacy driver use native endian, support legacy driver > requires the device to know native endian which I'm not sure your > device can do that. > > Thanks Yes, legacy requires guest native endianess, I think we don't need to worry about this because our transitional device should work in modern mode by default(legacy mode is the failover path we will never reach, get_features will fail if no ACCESS_PLATFORM), we don't support legacy device in vDPA. Thanks > > >> For vDPA, it has to support VIRTIO_1 and ACCESS_PLATFORM, so it must >> in modern mode. >> I think we don't need to worry about endianess for legacy mode. >> >> Thanks >> Zhu Lingshan >>> >>> >>>> + >>>>       vf->base = pcim_iomap_table(pdev); >>>>         adapter->pdev = pdev; >>> >> >