kernel/linux.git/drivers/of/device.c, branch v6.19.11

of: Clarify OF device context in of_match_device() comment

2025-07-30T22:49:06+00:00

Open Firmware abbreviation (OF) in of_match_device() comment is written in lowercase instead, which is mistaken for prepositional word "of" ([1], [2], [3], [4]) duplicate. Clarify the context. Link: https://lore.kernel.org/all/CAL_JsqLypcBCOVZ8yYWK0J_xc2Vcr+ANrX_3v4vN55Srp4RknQ@mail.gmail.com/ [1] Link: https://lore.kernel.org/all/20220926185852.GA2581083-robh@kernel.org/ [2] Link: https://lore.kernel.org/all/CAL_JsqL4GvgFYzGUfhW5pvm4wYGrFaj6gHOYZjnOMuk2zCz67w@mail.gmail.com/ [3] Link: https://lore.kernel.org/all/20220627173825.GA2637590-robh@kernel.org/ [4] Signed-off-by: Bagas Sanjaya Reviewed-by: Randy Dunlap Link: https://lore.kernel.org/r/20250730013113.11264-1-bagasdotme@gmail.com Signed-off-by: Rob Herring (Arm)

of: Simplify of_dma_set_restricted_buffer() to use of_for_each_phandle()

2025-05-05T21:18:05+00:00

Simplify of_dma_set_restricted_buffer() by using of_property_present() and of_for_each_phandle() iterator. Acked-by: Arnaud Pouliquen Link: https://lore.kernel.org/r/20250423-dt-memory-region-v2-v2-2-2fbd6ebd3c88@kernel.org Signed-off-by: Rob Herring (Arm)

iommu: Get DT/ACPI parsing into the proper probe path

2025-03-11T13:05:43+00:00

In hindsight, there were some crucial subtleties overlooked when moving {of,acpi}_dma_configure() to driver probe time to allow waiting for IOMMU drivers with -EPROBE_DEFER, and these have become an ever-increasing source of problems. The IOMMU API has some fundamental assumptions that iommu_probe_device() is called for every device added to the system, in the order in which they are added. Calling it in a random order or not at all dependent on driver binding leads to malformed groups, a potential lack of isolation for devices with no driver, and all manner of unexpected concurrency and race conditions. We've attempted to mitigate the latter with point-fix bodges like iommu_probe_device_lock, but it's a losing battle and the time has come to bite the bullet and address the true source of the problem instead. The crux of the matter is that the firmware parsing actually serves two distinct purposes; one is identifying the IOMMU instance associated with a device so we can check its availability, the second is actually telling that instance about the relevant firmware-provided data for the device. However the latter also depends on the former, and at the time there was no good place to defer and retry that separately from the availability check we also wanted for client driver probe. Nowadays, though, we have a proper notion of multiple IOMMU instances in the core API itself, and each one gets a chance to probe its own devices upon registration, so we can finally make that work as intended for DT/IORT/VIOT platforms too. All we need is for iommu_probe_device() to be able to run the iommu_fwspec machinery currently buried deep in the wrong end of {of,acpi}_dma_configure(). Luckily it turns out to be surprisingly straightforward to bootstrap this transformation by pretty much just calling the same path twice. At client driver probe time, dev->driver is obviously set; conversely at device_add(), or a subsequent bus_iommu_probe(), any device waiting for an IOMMU really should *not* have a driver already, so we can use that as a condition to disambiguate the two cases, and avoid recursing back into the IOMMU core at the wrong times. Obviously this isn't the nicest thing, but for now it gives us a functional baseline to then unpick the layers in between without many more awkward cross-subsystem patches. There are some minor side-effects like dma_range_map potentially being created earlier, and some debug prints being repeated, but these aren't significantly detrimental. Let's make things work first, then deal with making them nice. With the basic flow finally in the right order again, the next step is probably turning the bus->dma_configure paths inside-out, since all we really need from bus code is its notion of which device and input ID(s) to parse the common firmware properties with... Acked-by: Bjorn Helgaas # pci-driver.c Acked-by: Rob Herring (Arm) # of/device.c Signed-off-by: Robin Murphy Reviewed-by: Lorenzo Pieralisi Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/e3b191e6fd6ca9a1e84c5e5e40044faf97abb874.1740753261.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

OF: Simplify of_iommu_configure()

2024-07-04T13:36:04+00:00

We no longer have a notion of partially-initialised fwspecs existing, and we also no longer need to use an iommu_ops pointer to return status to of_dma_configure(). Clean up the remains of those, which lends itself to clarifying the logic around the dma_range_map allocation as well. Acked-by: Rob Herring (Arm) Tested-by: Jean-Philippe Brucker Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/61972f88e31a6eda8bf5852f0853951164279a3c.1719919669.git.robin.murphy@arm.com Signed-off-by: Will Deacon

dma-mapping: Simplify arch_setup_dma_ops()

2024-04-26T10:07:28+00:00

The dma_base, size and iommu arguments are only used by ARM, and can now easily be deduced from the device itself, so there's no need to pass them through the callchain as well. Acked-by: Rob Herring Reviewed-by: Christoph Hellwig Reviewed-by: Michael Kelley # For Hyper-V Reviewed-by: Jason Gunthorpe Tested-by: Hanjun Guo Signed-off-by: Robin Murphy Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/5291c2326eab405b1aa7693aa964e8d3cb7193de.1713523152.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

dma-mapping: Add helpers for dma_range_map bounds

2024-04-26T10:07:24+00:00

Several places want to compute the lower and/or upper bounds of a dma_range_map, so let's factor that out into reusable helpers. Acked-by: Rob Herring Reviewed-by: Christoph Hellwig Reviewed-by: Hanjun Guo # For arm64 Reviewed-by: Jason Gunthorpe Tested-by: Hanjun Guo Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/45ec52f033ec4dfb364e23f48abaf787f612fa53.1713523152.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

OF: Simplify DMA range calculations

2024-04-26T10:07:23+00:00

Juggling start, end, and size values for a range is somewhat redundant and a little hard to follow. Consolidate down to just using inclusive start and end, which saves us worrying about size overflows for full 64-bit ranges (note that passing a potentially-overflowed value through to arch_setup_dma_ops() is benign for all current implementations, and this is working towards removing that anyway). Acked-by: Rob Herring Reviewed-by: Jason Gunthorpe Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/3e0a72fe3d79eae660e4284bb32f2cb39868ccd7.1713523152.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

OF: Retire dma-ranges mask workaround

2024-04-26T10:07:22+00:00

The fixup adding 1 to the dma-ranges size may have been for the benefit of some early AMD Seattle DTs, or may have merely been a just-in-case, but either way anyone who might have deserved to get the message has hopefully seen the warning in the 9 years we've had it there. The modern dma_range_map mechanism should happily handle odd-sized ranges with no ill effect, so there's little need to care anyway now. Clean it up. Acked-by: Rob Herring Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/26620039901fdae52079ec1c8a4b2b324964a13e.1713523152.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

Merge tag 'iommu-updates-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

2024-01-18T23:16:57+00:00

Pull iommu updates from Joerg Roedel: "Core changes: - Fix race conditions in device probe path - Retire IOMMU bus_ops - Support for passing custom allocators to page table drivers - Clean up Kconfig around IOMMU_SVA - Support for sharing SVA domains with all devices bound to a mm - Firmware data parsing cleanup - Tracing improvements for iommu-dma code - Some smaller fixes and cleanups ARM-SMMU drivers: - Device-tree binding updates: - Add additional compatible strings for Qualcomm SoCs - Document Adreno clocks for Qualcomm's SM8350 SoC - SMMUv2: - Implement support for the ->domain_alloc_paging() callback - Ensure Secure context is restored following suspend of Qualcomm SMMU implementation - SMMUv3: - Disable stalling mode for the "quiet" context descriptor - Minor refactoring and driver cleanups Intel VT-d driver: - Cleanup and refactoring AMD IOMMU driver: - Improve IO TLB invalidation logic - Small cleanups and improvements Rockchip IOMMU driver: - DT binding update to add Rockchip RK3588 Apple DART driver: - Apple M1 USB4/Thunderbolt DART support - Cleanups Virtio IOMMU driver: - Add support for iotlb_sync_map - Enable deferred IO TLB flushes" * tag 'iommu-updates-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (66 commits) iommu: Don't reserve 0-length IOVA region iommu/vt-d: Move inline helpers to header files iommu/vt-d: Remove unused vcmd interfaces iommu/vt-d: Remove unused parameter of intel_pasid_setup_pass_through() iommu/vt-d: Refactor device_to_iommu() to retrieve iommu directly iommu/sva: Fix memory leak in iommu_sva_bind_device() dt-bindings: iommu: rockchip: Add Rockchip RK3588 iommu/dma: Trace bounce buffer usage when mapping buffers iommu/arm-smmu: Convert to domain_alloc_paging() iommu/arm-smmu: Pass arm_smmu_domain to internal functions iommu/arm-smmu: Implement IOMMU_DOMAIN_BLOCKED iommu/arm-smmu: Convert to a global static identity domain iommu/arm-smmu: Reorganize arm_smmu_domain_add_master() iommu/arm-smmu-v3: Remove ARM_SMMU_DOMAIN_NESTED iommu/arm-smmu-v3: Master cannot be NULL in arm_smmu_write_strtab_ent() iommu/arm-smmu-v3: Add a type for the STE iommu/arm-smmu-v3: disable stall for quiet_cd iommu/qcom: restore IOMMU state if needed iommu/arm-smmu-qcom: Add QCM2290 MDSS compatible iommu/arm-smmu-qcom: Add missing GMU entry to match table ...

of: device: Export of_device_make_bus_id()

2023-12-15T12:30:07+00:00

This helper is really handy to create unique device names based on their device tree path, we may need it outside of the OF core (in the NVMEM subsystem) so let's export it. As this helper has nothing patform specific, let's move it to of/device.c instead of of/platform.c so we can add its prototype to of_device.h. Signed-off-by: Miquel Raynal Acked-by: Rob Herring Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20231215111536.316972-2-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman