FROMLIST: of: parsing of multi #{iommu,msi}-cells in maps#844
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vijayanandjitta-oss wants to merge 3 commits intoqualcomm-linux:tech/mem/iommufrom
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FROMLIST: of: parsing of multi #{iommu,msi}-cells in maps#844vijayanandjitta-oss wants to merge 3 commits intoqualcomm-linux:tech/mem/iommufrom
vijayanandjitta-oss wants to merge 3 commits intoqualcomm-linux:tech/mem/iommufrom
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Since we now have quite a few users parsing "iommu-map" and "msi-map" properties, give them some wrappers to conveniently encapsulate the appropriate sets of property names. This will also make it easier to then change of_map_id() to correctly account for specifier cells. Reviewed-by: Rob Herring (Arm) <robh@kernel.org> Reviewed-by: Frank Li <Frank.Li@nxp.com> Acked-by: Marc Zyngier <maz@kernel.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Link: https://lore.kernel.org/all/20260325-parse_iommu_cells-v11-1-1fefa5c0e82c@oss.qualcomm.com/ [Conflict: irq-gic-its-msi-parent.c was refactored to split of_pmsi_get_msi_info() into of_pmsi_get_dev_id() and of_v5_pmsi_get_msi_info(); updated both of_map_id() calls.] Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
Change of_map_id() to take a pointer to struct of_phandle_args instead of passing target device node and translated IDs separately. Update all callers accordingly. Add an explicit filter_np parameter to of_map_id() and of_map_msi_id() to separate the filter input from the output. Previously, the target parameter served dual purpose: as an input filter (if non-NULL, only match entries targeting that node) and as an output (receiving the matched node with a reference held). Now filter_np is the explicit input filter and arg->np is the pure output. Previously, of_map_id() would call of_node_put() on the matched node when a filter was provided, making reference ownership inconsistent. Remove this internal of_node_put() call so that of_map_id() now always transfers ownership of the matched node reference to the caller via arg->np. Callers are now consistently responsible for releasing this reference with of_node_put(arg->np) when done. Suggested-by: Rob Herring (Arm) <robh@kernel.org> Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Signed-off-by: Charan Teja Kalla <charan.kalla@oss.qualcomm.com> Link: https://lore.kernel.org/all/20260325-parse_iommu_cells-v11-2-1fefa5c0e82c@oss.qualcomm.com/ [Conflict: irq-gic-its-msi-parent.c was refactored to split of_pmsi_get_msi_info() into of_pmsi_get_dev_id() and of_v5_pmsi_get_msi_info(); updated both of_map_id() calls.] Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
So far our parsing of {iommu,msi}-map properties has always blindly
assumed that the output specifiers will always have exactly 1 cell.
This typically does happen to be the case, but is not actually enforced
(and the PCI msi-map binding even explicitly states support for 0 or 1
cells) - as a result we've now ended up with dodgy DTs out in the field
which depend on this behaviour to map a 1-cell specifier for a 2-cell
provider, despite that being bogus per the bindings themselves.
Since there is some potential use in being able to map at least single
input IDs to multi-cell output specifiers (and properly support 0-cell
outputs as well), add support for properly parsing and using the target
nodes' #cells values, albeit with the unfortunate complication of still
having to work around expectations of the old behaviour too.
Since there are multi-cell output specifiers, the callers of of_map_id()
may need to get the exact cell output value for further processing.
Update of_map_id() to set args_count in the output to reflect the actual
number of output specifier cells.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Charan Teja Kalla <charan.kalla@oss.qualcomm.com>
Link: https://lore.kernel.org/all/65f76d05-1474-46d3-aa71-4acfe86c5718@oss.qualcomm.com/
Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
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This series adds #{iommu,msi}-cells support in maps .
So far our parsing of {iommu,msi}-map properties has always blindly
assumed that the output specifiers will always have exactly 1 cell.
This typically does happen to be the case, but is not actually enforced
(and the PCI msi-map binding even explicitly states support for 0 or 1
cells) - as a result we've now ended up with dodgy DTs out in the field
which depend on this behaviour to map a 1-cell specifier for a 2-cell
provider, despite that being bogus per the bindings themselves.
Since there is some potential use[1] in being able to map at least
single input IDs to multi-cell output specifiers (and properly support
0-cell outputs as well), add support for properly parsing and using the
target nodes' #cells values, albeit with the unfortunate complication of
still having to work around expectations of the old behaviour too.
-- Robin.
Unlike single #{}-cell, it is complex to establish a linear relation
between input 'id' and output specifier for multi-cell properties, thus
it is always expected that len never going to be > 1.
[1] https://lore.kernel.org/all/20250627-video_cb-v3-0-51e18c0ffbce@quicinc.com/
[2] PR for iommu-map dtschema: devicetree-org/dt-schema#184
Link: https://lore.kernel.org/all/20260325-parse_iommu_cells-v11-0-1fefa5c0e82c@oss.qualcomm.com/