linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jean-Philippe Brucker <jean-philippe@linaro.org>
To: Auger Eric <eric.auger@redhat.com>
Cc: linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-acpi@vger.kernel.org, devicetree@vger.kernel.org,
	iommu@lists.linux-foundation.org, joro@8bytes.org,
	robh+dt@kernel.org, mark.rutland@arm.com,
	lorenzo.pieralisi@arm.com, guohanjun@huawei.com,
	sudeep.holla@arm.com, rjw@rjwysocki.net, lenb@kernel.org,
	will@kernel.org, robin.murphy@arm.com, bhelgaas@google.com,
	jonathan.cameron@huawei.com, zhangfei.gao@linaro.org
Subject: Re: [PATCH v3 08/13] iommu/arm-smmu-v3: Propate ssid_bits
Date: Wed, 18 Dec 2019 17:08:34 +0100	[thread overview]
Message-ID: <20191218160834.GG2371701@myrica> (raw)
In-Reply-To: <466bbc57-79d4-274c-67bc-4ed591da9968@redhat.com>

On Tue, Dec 17, 2019 at 06:07:26PM +0100, Auger Eric wrote:
> Hi Jean,
> 
> On 12/9/19 7:05 PM, Jean-Philippe Brucker wrote:
> 
> s/Propate/Propagate in the commit title.
> > Now that we support substream IDs, initialize s1cdmax with the number of
> > SSID bits supported by a master and the SMMU.
> > 
> > Context descriptor tables are allocated once for the first master
> > attached to a domain. Therefore attaching multiple devices with
> > different SSID sizes is tricky, and we currently don't support it.
> > 
> > As a future improvement it would be nice to at least support attaching a
> > SSID-capable device to a domain that isn't using SSID, by reallocating
> > the SSID table.
> Isn't that use case relevant (I mean using both devices in a non SSID
> use case). For platform devices you can work this around with FW but for
> PCI devices?

Normally each device gets its own domain. Especially since PASID is a PCI
Express capability, I expect them to be properly isolated with ACS, each
with its own IOMMU group. So I don't think this is too relevant for the
moment, it would be a quirk for a broken system.

Thanks,
Jean

  reply	other threads:[~2019-12-18 16:08 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-12-09 18:05 [PATCH v3 00/13] iommu: Add PASID support to Arm SMMUv3 Jean-Philippe Brucker
2019-12-09 18:05 ` [PATCH v3 01/13] iommu/arm-smmu-v3: Drop __GFP_ZERO flag from DMA allocation Jean-Philippe Brucker
2019-12-13 16:45   ` Jonathan Cameron
2019-12-17 10:59   ` Auger Eric
2019-12-09 18:05 ` [PATCH v3 02/13] dt-bindings: document PASID property for IOMMU masters Jean-Philippe Brucker
2019-12-09 18:05 ` [PATCH v3 03/13] iommu/arm-smmu-v3: Support platform SSID Jean-Philippe Brucker
2019-12-17 11:05   ` Auger Eric
2019-12-17 15:21     ` Jean-Philippe Brucker
2019-12-17 16:46       ` Auger Eric
2019-12-18 10:17   ` Auger Eric
2019-12-18 16:06     ` Jean-Philippe Brucker
2019-12-09 18:05 ` [PATCH v3 04/13] ACPI/IORT: Support PASID for platform devices Jean-Philippe Brucker
2019-12-17 13:27   ` Auger Eric
2019-12-09 18:05 ` [PATCH v3 05/13] iommu/arm-smmu-v3: Prepare arm_smmu_s1_cfg for SSID support Jean-Philippe Brucker
2019-12-17 13:27   ` Auger Eric
2019-12-09 18:05 ` [PATCH v3 06/13] iommu/arm-smmu-v3: Add context descriptor tables allocators Jean-Philippe Brucker
2019-12-17 13:36   ` Auger Eric
2019-12-09 18:05 ` [PATCH v3 07/13] iommu/arm-smmu-v3: Add support for Substream IDs Jean-Philippe Brucker
2019-12-17 16:43   ` Auger Eric
2019-12-18 16:07     ` Jean-Philippe Brucker
2019-12-18 16:59       ` Auger Eric
2019-12-18 17:03   ` Auger Eric
2019-12-09 18:05 ` [PATCH v3 08/13] iommu/arm-smmu-v3: Propate ssid_bits Jean-Philippe Brucker
2019-12-17 17:07   ` Auger Eric
2019-12-18 16:08     ` Jean-Philippe Brucker [this message]
2019-12-18 17:00       ` Auger Eric
2019-12-09 18:05 ` [PATCH v3 09/13] iommu/arm-smmu-v3: Handle failure of arm_smmu_write_ctx_desc() Jean-Philippe Brucker
2019-12-17 17:24   ` Auger Eric
2019-12-09 18:05 ` [PATCH v3 10/13] iommu/arm-smmu-v3: Add second level of context descriptor table Jean-Philippe Brucker
2019-12-13 17:07   ` Jonathan Cameron
2019-12-18  9:59   ` Auger Eric
2019-12-18 16:10     ` Jean-Philippe Brucker
2019-12-09 18:05 ` [PATCH v3 11/13] iommu/arm-smmu-v3: Improve add_device() error handling Jean-Philippe Brucker
2019-12-09 18:05 ` [PATCH v3 12/13] PCI/ATS: Add PASID stubs Jean-Philippe Brucker
2019-12-10 21:07   ` Bjorn Helgaas
2019-12-18 10:02   ` Auger Eric
2019-12-09 18:05 ` [PATCH v3 13/13] iommu/arm-smmu-v3: Add support for PCI PASID Jean-Philippe Brucker
2019-12-18 10:17   ` Auger Eric
2019-12-18 16:13     ` Jean-Philippe Brucker
2019-12-13 17:10 ` [PATCH v3 00/13] iommu: Add PASID support to Arm SMMUv3 Jonathan Cameron

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191218160834.GG2371701@myrica \
    --to=jean-philippe@linaro.org \
    --cc=bhelgaas@google.com \
    --cc=devicetree@vger.kernel.org \
    --cc=eric.auger@redhat.com \
    --cc=guohanjun@huawei.com \
    --cc=iommu@lists.linux-foundation.org \
    --cc=jonathan.cameron@huawei.com \
    --cc=joro@8bytes.org \
    --cc=lenb@kernel.org \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=lorenzo.pieralisi@arm.com \
    --cc=mark.rutland@arm.com \
    --cc=rjw@rjwysocki.net \
    --cc=robh+dt@kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=sudeep.holla@arm.com \
    --cc=will@kernel.org \
    --cc=zhangfei.gao@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).