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| author | Robin Murphy <robin.murphy@arm.com> | 2026-06-03 10:13:14 +0300 |
|---|---|---|
| committer | Rob Herring (Arm) <robh@kernel.org> | 2026-06-12 18:25:39 +0300 |
| commit | ccb2fd725d411265df8f7ce12a66c226b16014e6 (patch) | |
| tree | 530cf5edfa1ae3b8ab3ccac46be9df1603a28fc2 /include/linux | |
| parent | f71f07bee9b56b94f7828cf3082ea19ec590de36 (diff) | |
| download | linux-ccb2fd725d411265df8f7ce12a66c226b16014e6.tar.xz | |
of: Respect #{iommu,msi}-cells 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 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>
Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
Link: https://patch.msgid.link/20260603-parse_iommu_cells-v16-3-dc509dacb19a@oss.qualcomm.com
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/of.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/include/linux/of.h b/include/linux/of.h index ea50b45d9ff7..374b249766a2 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -465,7 +465,8 @@ const char *of_prop_next_string(const struct property *prop, const char *cur); bool of_console_check(const struct device_node *dn, char *name, int index); int of_map_id(const struct device_node *np, u32 id, - const char *map_name, const char *map_mask_name, + const char *map_name, const char *cells_name, + const char *map_mask_name, struct device_node * const *filter_np, struct of_phandle_args *arg); @@ -950,7 +951,8 @@ static inline void of_property_clear_flag(struct property *p, unsigned long flag } static inline int of_map_id(const struct device_node *np, u32 id, - const char *map_name, const char *map_mask_name, + const char *map_name, const char *cells_name, + const char *map_mask_name, struct device_node * const *filter_np, struct of_phandle_args *arg) { |