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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 30143C433EF for ; Mon, 11 Oct 2021 05:50:12 +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 BF71161027 for ; Mon, 11 Oct 2021 05:50:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org BF71161027 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org 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:MIME-Version:In-Reply-To:References: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ZoTfZRDxMUoUpep5TGsTEf9+7sdb8h6Yr8HEHqlX4GU=; b=CeGmPsC7lG1Pad uvNzYhbvVnL1oRdjD8iffw5A7VLDIrosWpEdkLajZvT3JOMq1vzWpm5rm6oylwcv94r129mnZfCem oOBCz0dAQmdcV+CrF9qXSlH9CphgQVZVSphuYy1FVUOlRmJ6jrn0YwwSnoc7hiIB1+ci76g+/+Lb7 hNoTJJWHLSaUAeYH3dRggp7PPnbfJF/WAv3kT9Gkf9xdYefuXhME9AgRmCLsLIcOdA5MxTDumwjoQ cqB08Yk6XZCGu0YwNRNuf2dkgSQoax1bfHhyFiFVf5ckfY9iJzLe3qxzCzfYTO/1vMxd1h4Xokba9 3BY6X+Khi237wkbC9BBw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mZoA0-007pCY-Tg; Mon, 11 Oct 2021 05:47:41 +0000 Received: from szxga01-in.huawei.com ([45.249.212.187]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mZo9w-007pAs-Hv for linux-arm-kernel@lists.infradead.org; Mon, 11 Oct 2021 05:47:38 +0000 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4HSSPd6HWWzbn0Z; Mon, 11 Oct 2021 13:43:01 +0800 (CST) Received: from dggema774-chm.china.huawei.com (10.1.198.216) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2308.8; Mon, 11 Oct 2021 13:47:28 +0800 Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by dggema774-chm.china.huawei.com (10.1.198.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.8; Mon, 11 Oct 2021 13:47:26 +0800 Received: from lhreml710-chm.china.huawei.com ([169.254.81.184]) by lhreml710-chm.china.huawei.com ([169.254.81.184]) with mapi id 15.01.2308.008; Mon, 11 Oct 2021 06:47:24 +0100 From: Shameerali Kolothum Thodi To: Jon Nettleton , Robin Murphy CC: linux-arm-kernel , "ACPI Devel Maling List" , Linux IOMMU , Linuxarm , "Steven Price" , "Guohanjun (Hanjun Guo)" , yangyicong , Sami Mujawar , Will Deacon , wanghuiqiang Subject: RE: [PATCH v7 1/9] iommu: Introduce a union to struct iommu_resv_region Thread-Topic: [PATCH v7 1/9] iommu: Introduce a union to struct iommu_resv_region Thread-Index: AQHXidEdw4nQ2pDnVEWq+ST9RUOUTKvJV6SAgAE56YCAAyElcA== Date: Mon, 11 Oct 2021 05:47:24 +0000 Message-ID: <9df40b8f09f6488382f25f419519a2fa@huawei.com> References: <20210805080724.480-1-shameerali.kolothum.thodi@huawei.com> <20210805080724.480-2-shameerali.kolothum.thodi@huawei.com> In-Reply-To: Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.47.25.32] MIME-Version: 1.0 X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211010_224737_041568_7803FA9F X-CRM114-Status: GOOD ( 26.44 ) 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 > -----Original Message----- > From: Jon Nettleton [mailto:jon@solid-run.com] > Sent: 09 October 2021 07:58 > To: Robin Murphy > Cc: Shameerali Kolothum Thodi ; > linux-arm-kernel ; ACPI Devel Maling > List ; Linux IOMMU > ; Linuxarm ; > Steven Price ; Guohanjun (Hanjun Guo) > ; yangyicong ; Sami > Mujawar ; Will Deacon ; > wanghuiqiang > Subject: Re: [PATCH v7 1/9] iommu: Introduce a union to struct > iommu_resv_region > > On Fri, Oct 8, 2021 at 2:14 PM Robin Murphy > wrote: > > > > On 2021-08-05 09:07, Shameer Kolothum wrote: > > > A union is introduced to struct iommu_resv_region to hold any > > > firmware specific data. This is in preparation to add support for > > > IORT RMR reserve regions and the union now holds the RMR specific > > > information. > > > > > > Signed-off-by: Shameer Kolothum > > > > > > --- > > > include/linux/iommu.h | 11 +++++++++++ > > > 1 file changed, 11 insertions(+) > > > > > > diff --git a/include/linux/iommu.h b/include/linux/iommu.h index > > > 32d448050bf7..bd0e4641c569 100644 > > > --- a/include/linux/iommu.h > > > +++ b/include/linux/iommu.h > > > @@ -114,6 +114,13 @@ enum iommu_resv_type { > > > IOMMU_RESV_SW_MSI, > > > }; > > > > > > +struct iommu_iort_rmr_data { > > > +#define IOMMU_RMR_REMAP_PERMITTED (1 << 0) > > > + u32 flags; > > > + u32 sid; /* Stream Id associated with RMR entry */ > > > + void *smmu; /* Associated IORT SMMU node pointer */ > > > +}; > > > > Do we really need to duplicate all this data? AFAICS we could just > > save the acpi_iort_rmr pointer in the iommu_resv_region (with a > > forward declaration here if necessary) and defer parsing its actual > > mappings until the point where we can directly consume the results. > > From earlier discussions on this patchset, the original goal was also for > device-tree mechanisms to be able to hook into this code to support similar > RMR's and SMMU initialization, just not through the ACPI / IORT path. Yes. IIRC, there were some earlier attempts to have DT support for reserved regions and there was a suggestion to provide generic interfaces so that when DT solution comes up it is easier to add the support. Thanks, Shameer > > > > Robin. > > > > > + > > > /** > > > * struct iommu_resv_region - descriptor for a reserved memory region > > > * @list: Linked list pointers > > > @@ -121,6 +128,7 @@ enum iommu_resv_type { > > > * @length: Length of the region in bytes > > > * @prot: IOMMU Protection flags (READ/WRITE/...) > > > * @type: Type of the reserved region > > > + * @rmr: ACPI IORT RMR specific data > > > */ > > > struct iommu_resv_region { > > > struct list_head list; > > > @@ -128,6 +136,9 @@ struct iommu_resv_region { > > > size_t length; > > > int prot; > > > enum iommu_resv_type type; > > > + union { > > > + struct iommu_iort_rmr_data rmr; > > > + } fw_data; > > > }; > > > > > > /** > > > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel