From nobody Fri May 06 18:31:47 2022 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 8F3071AC19E3; Fri, 6 May 2022 18:31:56 +0000 (UTC) (envelope-from br@bsdpad.com) Received: from mail.bsdpad.com (mail.bsdpad.com [116.202.106.248]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4KvzgH6Hwnz4mjm; Fri, 6 May 2022 18:31:55 +0000 (UTC) (envelope-from br@bsdpad.com) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=bsdpad.com; s=20201212; h=Subject:To:From; bh=+7v3i6NYcdyhGoyam3ADKyT1lQjfurhaBBSe9SDdkpM=; b=k2S0h76IE0eD8OgVomkQFFiNtd GUlreFQT2LFR+M02pI0hzc8gesyHZVC+iZJo/vdhXWGqR/BPzd4WN5bQQmwO+O855LzHS85QjySmV sYeY7TqHE5nutQbGXAUlIx4T2e5DDIZu2MNced7FpCuLVTqIUI3OTzx/UZwObdT5yNSTCqu0GHVJt HwZtP+SDFNK6K/OzoQLwLmmcT7v/mvuNuUHTGaLUyA5pDCC5IzyhSz1CgJ/iUdJASBhRRvscBnPxi 2OfS4w3JIfp4SaWhy+MYSWs7HWFwGD9C78XpLv1CacFxyjtBzRtUamgtX2Eb+WzmPmJJ9H/oPsE1L f25A7CnA==; Received: from localhost ([127.0.0.1] helo=bsdpad.com) by mail.bsdpad.com with smtp (Exim 4.94 (FreeBSD)) (envelope-from ) id 1nn2jz-000BZE-2I; Fri, 06 May 2022 19:31:47 +0100 Received: by bsdpad.com (nbSMTP-1.00) for uid 1001 br@bsdpad.com; Fri, 6 May 2022 19:31:47 +0100 (BST) Date: Fri, 6 May 2022 19:31:47 +0100 From: Ruslan Bukin To: Kyle Evans Cc: Ravi Pokala , src-committers , "" , dev-commits-src-main@freebsd.org Subject: Re: 0b6bacc7874f - main - Add ofw_bus_iommu_map() that maps PCI requester ID to an IOMMU specifier based on "iommu-map" DTS property. Message-ID: References: <202205061551.246FpO6o060060@gitrepo.freebsd.org> <450C9313-CB5A-4DCA-97FB-40FC87886F00@panasas.com> List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 4KvzgH6Hwnz4mjm X-Spamd-Bar: --- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=bsdpad.com header.s=20201212 header.b=k2S0h76I; dmarc=none; spf=pass (mx1.freebsd.org: domain of br@bsdpad.com designates 116.202.106.248 as permitted sender) smtp.mailfrom=br@bsdpad.com X-Spamd-Result: default: False [-3.20 / 15.00]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-0.999]; R_DKIM_ALLOW(-0.20)[bsdpad.com:s=20201212]; FREEFALL_USER(0.00)[br]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; R_SPF_ALLOW(-0.20)[+mx]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[freebsd.org]; NEURAL_HAM_LONG(-1.00)[-1.000]; RCPT_COUNT_FIVE(0.00)[5]; DKIM_TRACE(0.00)[bsdpad.com:+]; NEURAL_HAM_SHORT(-1.00)[-1.000]; MLMMJ_DEST(0.00)[dev-commits-src-all,dev-commits-src-main]; FORGED_SENDER(0.30)[br@freebsd.org,br@bsdpad.com]; MIME_TRACE(0.00)[0:+]; RCVD_TLS_LAST(0.00)[]; ASN(0.00)[asn:24940, ipnet:116.202.0.0/16, country:DE]; FROM_NEQ_ENVFROM(0.00)[br@freebsd.org,br@bsdpad.com]; RCVD_COUNT_TWO(0.00)[2] X-ThisMailContainsUnwantedMimeParts: N On Fri, May 06, 2022 at 09:37:36AM -0700, Kyle Evans wrote: > On Fri, May 6, 2022 at 9:25 AM Ravi Pokala wrote: > > > > -----Original Message----- > > From: on behalf of Ruslan Bukin > > Date: 2022-05-06, Friday at 08:51 > > To: , , > > Subject: git: 0b6bacc7874f - main - Add ofw_bus_iommu_map() that maps PCI requester ID to an IOMMU specifier based on "iommu-map" DTS property. > > > > The branch main has been updated by br: > > > > URL: https://cgit.FreeBSD.org/src/commit/?id=0b6bacc7874f9c68ad35b06f1a7614171eb9ab10 > > > > commit 0b6bacc7874f9c68ad35b06f1a7614171eb9ab10 > > Author: Ruslan Bukin > > AuthorDate: 2022-05-06 15:41:11 +0000 > > Commit: Ruslan Bukin > > CommitDate: 2022-05-06 15:48:04 +0000 > > > > Add ofw_bus_iommu_map() that maps PCI requester ID to an IOMMU > > specifier based on "iommu-map" DTS property. > > > > Sponsored by: UKRI > > --- > > sys/dev/ofw/ofw_bus_subr.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ > > sys/dev/ofw/ofw_bus_subr.h | 3 ++- > > 2 files changed, 46 insertions(+), 1 deletion(-) > > > > diff --git a/sys/dev/ofw/ofw_bus_subr.c b/sys/dev/ofw/ofw_bus_subr.c > > index ea57d1086779..408d554b3c7f 100644 > > --- a/sys/dev/ofw/ofw_bus_subr.c > > +++ b/sys/dev/ofw/ofw_bus_subr.c > > @@ -491,6 +491,50 @@ ofw_bus_msimap(phandle_t node, uint16_t pci_rid, phandle_t *msi_parent, > > return (err); > > } > > > > +int > > +ofw_bus_iommu_map(phandle_t node, uint16_t pci_rid, phandle_t *iommu_parent, > > + uint32_t *iommu_rid) > > +{ > > + pcell_t mask, iommu_base, rid_base, rid_length; > > + uint32_t masked_rid; > > + pcell_t map[4]; > > + ssize_t len; > > + int err, i; > > + > > + len = OF_getproplen(node, "iommu-map"); > > + if (len <= 0) > > + return (ENOENT); > > + if (len > sizeof(map)) > > + return (ENOMEM); > > + > > + len = OF_getencprop(node, "iommu-map", map, 16); > > + > > + err = ENOENT; > > + mask = 0xffffffff; > > + OF_getencprop(node, "iommu-map-mask", &mask, sizeof(mask)); > > + > > + masked_rid = pci_rid & mask; > > + for (i = 0; i < len; i += 4) { > > + rid_base = map[i + 0]; > > + rid_length = map[i + 3]; > > > > Hi Ruslan, > > > > I'm confused by this. 'map' is declared as a 4-element array, which means 'map[i + 0]' and 'map[i + 3]' are both only valid when 'i' is 0. But 'i' is the loop iterator; doesn't that mean you're accessing outside the array after the 0th time through the loop? > > > > The comparison looks like it's wrong and inherited from > ofw_bus_msimap() -- i is in terms of # cells, OF_getencprop returns > size in bytes, This version only holds one mapping (four cells) at a > time, so the intention is just one iteration through the loop. > > We'll need to extend this at some point, the M1 FDT has 3 4-cell mappings > here. ofw_bus_msimap() was almost an exact fit, and an adapted version > is what I use in my m1 branch. iommu-map property is an arbitrary number of tuples of (rid-base,iommu,iommu-base,length). Do you mean that some of the items in the tuple could occupy more than one 32-bit cell? I grepped DTS tree, so far each of occurrence takes just 1 cell. Ruslan