From: Hanjun Guo <guohanjun@huawei.com> To: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: devicetree@vger.kernel.org, Marc Zyngier <maz@kernel.org>, Makarand Pawagi <makarand.pawagi@nxp.com>, linux-pci@vger.kernel.org, Catalin Marinas <catalin.marinas@arm.com>, Diana Craciun <diana.craciun@oss.nxp.com>, "Rafael J. Wysocki" <rjw@rjwysocki.net>, Robin Murphy <robin.murphy@arm.com>, linux-acpi@vger.kernel.org, iommu@lists.linux-foundation.org, Rob Herring <robh+dt@kernel.org>, Sudeep Holla <sudeep.holla@arm.com>, Bjorn Helgaas <bhelgaas@google.com>, Will Deacon <will@kernel.org>, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 01/12] ACPI/IORT: Make iort_match_node_callback walk the ACPI namespace for NC Date: Tue, 30 Jun 2020 11:06:41 +0800 [thread overview] Message-ID: <765078e7-b3ec-af5d-0405-7834ba0f120a@huawei.com> (raw) In-Reply-To: <20200629090551.GA28873@e121166-lin.cambridge.arm.com> On 2020/6/29 17:05, Lorenzo Pieralisi wrote: > On Mon, Jun 29, 2020 at 12:24:43PM +0800, Hanjun Guo wrote: >> Hi Lorenzo, >> >> On 2020/6/19 16:20, Lorenzo Pieralisi wrote: >>> When the iort_match_node_callback is invoked for a named component >>> the match should be executed upon a device with an ACPI companion. >>> >>> For devices with no ACPI companion set-up the ACPI device tree must be >>> walked in order to find the first parent node with a companion set and >>> check the parent node against the named component entry to check whether >>> there is a match and therefore an IORT node describing the in/out ID >>> translation for the device has been found. >>> >>> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> >>> Cc: Will Deacon <will@kernel.org> >>> Cc: Hanjun Guo <guohanjun@huawei.com> >>> Cc: Sudeep Holla <sudeep.holla@arm.com> >>> Cc: Catalin Marinas <catalin.marinas@arm.com> >>> Cc: Robin Murphy <robin.murphy@arm.com> >>> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> >>> --- >>> drivers/acpi/arm64/iort.c | 20 ++++++++++++++++++-- >>> 1 file changed, 18 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c >>> index 28a6b387e80e..5eee81758184 100644 >>> --- a/drivers/acpi/arm64/iort.c >>> +++ b/drivers/acpi/arm64/iort.c >>> @@ -264,15 +264,31 @@ static acpi_status iort_match_node_callback(struct acpi_iort_node *node, >>> if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT) { >>> struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL }; >>> - struct acpi_device *adev = to_acpi_device_node(dev->fwnode); >>> + struct acpi_device *adev; >>> struct acpi_iort_named_component *ncomp; >>> + struct device *nc_dev = dev; >>> + >>> + /* >>> + * Walk the device tree to find a device with an >>> + * ACPI companion; there is no point in scanning >>> + * IORT for a device matching a named component if >>> + * the device does not have an ACPI companion to >>> + * start with. >>> + */ >>> + do { >>> + adev = ACPI_COMPANION(nc_dev); >>> + if (adev) >>> + break; >>> + >>> + nc_dev = nc_dev->parent; >>> + } while (nc_dev); >> >> I'm lost here, we need the ACPI_COMPANION (the same as >> to_acpi_device_node()) of the device, but why do we need to go >> up to find the parent node? > > For devices that aren't described in the DSDT - IORT translations > are determined by their ACPI parent device. Do you see/Have you > found any issue with this approach ? The spec says "Describes the IO relationships between devices represented in the ACPI namespace.", and in section 3.1.1.3 Named component node, it says: "Named component nodes are used to describe devices that are also included in the Differentiated System Description Table (DSDT). See [ACPI]." So from my understanding, the IORT spec for now, can only do ID translations for devices in the DSDT. > >> For a platform device, if I use its parent's full path name for >> its named component entry, then it will match, but this will violate >> the IORT spec. > > Can you elaborate on this please I don't get the point you > are making. For example, device A is not described in DSDT so can't represent as a NC node in IORT. Device B can be described in DSDT and it is the parent of device A, so device B can be represented in IORT with memory access properties and node flags with Substream width and Stall supported info. When we trying to translate device A's ID, we reuse all the memory access properties and node flags from its parent (device B), but will it the same? So the IORT spec don't support this, at least it's pretty vague I think. Thanks Hanjun _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
next prev parent reply other threads:[~2020-06-30 3:06 UTC|newest] Thread overview: 82+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-05-21 12:59 [PATCH 00/12] ACPI/OF: Upgrade MSI/IOMMU ID mapping APIs Lorenzo Pieralisi 2020-05-21 12:59 ` [PATCH 01/12] ACPI/IORT: Make iort_match_node_callback walk the ACPI namespace for NC Lorenzo Pieralisi 2020-05-21 12:59 ` [PATCH 02/12] ACPI/IORT: Make iort_get_device_domain IRQ domain agnostic Lorenzo Pieralisi 2020-05-21 19:56 ` Bjorn Helgaas 2020-05-21 12:59 ` [PATCH 03/12] ACPI/IORT: Make iort_msi_map_rid() PCI agnostic Lorenzo Pieralisi 2020-05-21 13:00 ` [PATCH 04/12] ACPI/IORT: Remove useless PCI bus walk Lorenzo Pieralisi 2020-05-21 13:00 ` [PATCH 05/12] ACPI/IORT: Add an input ID to acpi_dma_configure() Lorenzo Pieralisi 2020-05-21 13:00 ` [PATCH 06/12] of/iommu: Make of_map_rid() PCI agnostic Lorenzo Pieralisi 2020-05-21 22:47 ` Rob Herring 2020-06-04 14:27 ` Lorenzo Pieralisi 2020-05-21 13:00 ` [PATCH 07/12] of/device: Add input id to of_dma_configure() Lorenzo Pieralisi 2020-05-21 23:02 ` Rob Herring 2020-06-04 14:49 ` Lorenzo Pieralisi 2020-05-21 13:00 ` [PATCH 08/12] of/irq: make of_msi_map_get_device_domain() bus agnostic Lorenzo Pieralisi 2020-05-21 19:57 ` Bjorn Helgaas 2020-05-21 13:00 ` [PATCH 09/12] dt-bindings: arm: fsl: Add msi-map device-tree binding for fsl-mc bus Lorenzo Pieralisi 2020-05-21 23:10 ` Rob Herring 2020-05-22 9:42 ` Robin Murphy 2020-05-22 9:57 ` Diana Craciun OSS 2020-05-22 14:08 ` Rob Herring 2020-05-22 14:34 ` Robin Murphy 2020-05-22 14:02 ` Rob Herring 2020-05-22 15:38 ` Laurentiu Tudor 2020-05-21 13:00 ` [PATCH 10/12] of/irq: Make of_msi_map_rid() PCI bus agnostic Lorenzo Pieralisi 2020-05-21 23:17 ` Rob Herring 2020-06-04 15:08 ` Lorenzo Pieralisi 2020-05-21 13:00 ` [PATCH 11/12] bus/fsl-mc: Refactor the MSI domain creation in the DPRC driver Lorenzo Pieralisi 2020-05-21 13:00 ` [PATCH 12/12] bus: fsl-mc: Add ACPI support for fsl-mc Lorenzo Pieralisi 2020-05-21 15:03 ` Laurentiu Tudor 2020-05-22 5:32 ` Makarand Pawagi 2020-05-22 9:53 ` Lorenzo Pieralisi 2020-06-19 8:20 ` [PATCH v2 00/12] ACPI/OF: Upgrade MSI/IOMMU ID mapping APIs Lorenzo Pieralisi 2020-06-19 8:20 ` [PATCH v2 01/12] ACPI/IORT: Make iort_match_node_callback walk the ACPI namespace for NC Lorenzo Pieralisi 2020-06-29 4:24 ` Hanjun Guo 2020-06-29 9:05 ` Lorenzo Pieralisi 2020-06-30 3:06 ` Hanjun Guo [this message] 2020-06-30 10:24 ` Lorenzo Pieralisi 2020-06-30 13:04 ` Hanjun Guo 2020-07-01 16:12 ` Robin Murphy 2020-07-02 8:22 ` Hanjun Guo 2020-07-09 9:21 ` Lorenzo Pieralisi 2020-07-09 12:48 ` Hanjun Guo 2020-08-18 0:49 ` Hanjun Guo 2020-06-19 8:20 ` [PATCH v2 02/12] ACPI/IORT: Make iort_get_device_domain IRQ domain agnostic Lorenzo Pieralisi 2020-06-19 8:20 ` [PATCH v2 03/12] ACPI/IORT: Make iort_msi_map_rid() PCI agnostic Lorenzo Pieralisi 2020-07-15 9:15 ` Lorenzo Pieralisi 2020-07-21 14:59 ` Bjorn Helgaas 2020-07-27 6:06 ` [EXT] " Makarand Pawagi 2020-06-19 8:20 ` [PATCH v2 04/12] ACPI/IORT: Remove useless PCI bus walk Lorenzo Pieralisi 2020-06-19 8:20 ` [PATCH v2 05/12] ACPI/IORT: Add an input ID to acpi_dma_configure() Lorenzo Pieralisi 2020-07-09 9:35 ` Lorenzo Pieralisi 2020-07-15 9:13 ` Lorenzo Pieralisi 2020-07-28 12:48 ` Lorenzo Pieralisi 2020-07-28 13:00 ` Rafael J. Wysocki 2020-06-19 8:20 ` [PATCH v2 06/12] of/iommu: Make of_map_rid() PCI agnostic Lorenzo Pieralisi 2020-06-22 13:26 ` Joerg Roedel 2020-07-13 23:57 ` Rob Herring 2020-06-19 8:20 ` [PATCH v2 07/12] of/device: Add input id to of_dma_configure() Lorenzo Pieralisi 2020-06-30 21:50 ` Rob Herring 2020-06-19 8:20 ` [PATCH v2 08/12] dt-bindings: arm: fsl: Add msi-map device-tree binding for fsl-mc bus Lorenzo Pieralisi 2020-06-30 21:55 ` Rob Herring 2020-06-19 8:20 ` [PATCH v2 09/12] of/irq: make of_msi_map_get_device_domain() bus agnostic Lorenzo Pieralisi 2020-06-30 21:50 ` Rob Herring 2020-06-19 8:20 ` [PATCH v2 10/12] of/irq: Make of_msi_map_rid() PCI " Lorenzo Pieralisi 2020-06-30 21:56 ` Rob Herring 2020-06-19 8:20 ` [PATCH v2 11/12] bus/fsl-mc: Refactor the MSI domain creation in the DPRC driver Lorenzo Pieralisi 2020-07-15 13:05 ` Marc Zyngier 2020-06-19 8:20 ` [PATCH v2 12/12] bus: fsl-mc: Add ACPI support for fsl-mc Lorenzo Pieralisi 2020-07-01 16:55 ` Laurentiu Tudor 2020-07-09 9:19 ` Lorenzo Pieralisi 2020-07-09 9:26 ` [EXT] " Makarand Pawagi 2020-07-09 10:14 ` Laurentiu Tudor 2020-07-09 10:37 ` Makarand Pawagi 2020-07-09 10:39 ` Laurentiu Tudor 2020-07-09 10:47 ` Diana Craciun OSS 2020-07-09 10:52 ` Makarand Pawagi 2020-07-15 10:06 ` Lorenzo Pieralisi 2020-07-16 3:23 ` Makarand Pawagi 2020-07-16 7:57 ` Marc Zyngier 2020-07-20 16:54 ` [PATCH v2 00/12] ACPI/OF: Upgrade MSI/IOMMU ID mapping APIs Lorenzo Pieralisi 2020-07-21 4:28 ` [EXT] " Makarand Pawagi 2020-07-28 17:01 ` Catalin Marinas
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=765078e7-b3ec-af5d-0405-7834ba0f120a@huawei.com \ --to=guohanjun@huawei.com \ --cc=bhelgaas@google.com \ --cc=catalin.marinas@arm.com \ --cc=devicetree@vger.kernel.org \ --cc=diana.craciun@oss.nxp.com \ --cc=iommu@lists.linux-foundation.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=makarand.pawagi@nxp.com \ --cc=maz@kernel.org \ --cc=rjw@rjwysocki.net \ --cc=robh+dt@kernel.org \ --cc=robin.murphy@arm.com \ --cc=sudeep.holla@arm.com \ --cc=will@kernel.org \ --subject='Re: [PATCH v2 01/12] ACPI/IORT: Make iort_match_node_callback walk the ACPI namespace for NC' \ /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
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).