From d4b52f83f198310c871aa71816a26152eb3898c2 Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Wed, 3 Jun 2026 12:43:12 +0530 Subject: of: Add convenience wrappers for of_map_id() 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) Reviewed-by: Frank Li Acked-by: Marc Zyngier Acked-by: Bjorn Helgaas Signed-off-by: Robin Murphy Signed-off-by: Vijayanand Jitta Link: https://patch.msgid.link/20260603-parse_iommu_cells-v16-1-dc509dacb19a@oss.qualcomm.com Signed-off-by: Rob Herring (Arm) --- include/linux/of.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'include/linux') diff --git a/include/linux/of.h b/include/linux/of.h index 959786f8f196..721525334b4b 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -468,6 +468,12 @@ int of_map_id(const struct device_node *np, u32 id, const char *map_name, const char *map_mask_name, struct device_node **target, u32 *id_out); +int of_map_iommu_id(const struct device_node *np, u32 id, + struct device_node **target, u32 *id_out); + +int of_map_msi_id(const struct device_node *np, u32 id, + struct device_node **target, u32 *id_out); + phys_addr_t of_dma_get_max_cpu_address(struct device_node *np); struct kimage; @@ -948,6 +954,18 @@ static inline int of_map_id(const struct device_node *np, u32 id, return -EINVAL; } +static inline int of_map_iommu_id(const struct device_node *np, u32 id, + struct device_node **target, u32 *id_out) +{ + return -EINVAL; +} + +static inline int of_map_msi_id(const struct device_node *np, u32 id, + struct device_node **target, u32 *id_out) +{ + return -EINVAL; +} + static inline phys_addr_t of_dma_get_max_cpu_address(struct device_node *np) { return PHYS_ADDR_MAX; -- cgit v1.2.3 From f71f07bee9b56b94f7828cf3082ea19ec590de36 Mon Sep 17 00:00:00 2001 From: Charan Teja Kalla Date: Wed, 3 Jun 2026 12:43:13 +0530 Subject: of: Factor arguments passed to of_map_id() into a struct 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. Acked-by: Frank Li Suggested-by: Rob Herring (Arm) Suggested-by: Dmitry Baryshkov Signed-off-by: Charan Teja Kalla Signed-off-by: Vijayanand Jitta Link: https://patch.msgid.link/20260603-parse_iommu_cells-v16-2-dc509dacb19a@oss.qualcomm.com Signed-off-by: Rob Herring (Arm) --- include/linux/of.h | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) (limited to 'include/linux') diff --git a/include/linux/of.h b/include/linux/of.h index 721525334b4b..ea50b45d9ff7 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -466,13 +466,15 @@ 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, - struct device_node **target, u32 *id_out); + struct device_node * const *filter_np, + struct of_phandle_args *arg); int of_map_iommu_id(const struct device_node *np, u32 id, - struct device_node **target, u32 *id_out); + struct of_phandle_args *arg); int of_map_msi_id(const struct device_node *np, u32 id, - struct device_node **target, u32 *id_out); + struct device_node * const *filter_np, + struct of_phandle_args *arg); phys_addr_t of_dma_get_max_cpu_address(struct device_node *np); @@ -949,19 +951,21 @@ 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, - struct device_node **target, u32 *id_out) + struct device_node * const *filter_np, + struct of_phandle_args *arg) { return -EINVAL; } static inline int of_map_iommu_id(const struct device_node *np, u32 id, - struct device_node **target, u32 *id_out) + struct of_phandle_args *arg) { return -EINVAL; } static inline int of_map_msi_id(const struct device_node *np, u32 id, - struct device_node **target, u32 *id_out) + struct device_node * const *filter_np, + struct of_phandle_args *arg) { return -EINVAL; } -- cgit v1.2.3 From ccb2fd725d411265df8f7ce12a66c226b16014e6 Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Wed, 3 Jun 2026 12:43:14 +0530 Subject: 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 Signed-off-by: Charan Teja Kalla Signed-off-by: Vijayanand Jitta Link: https://patch.msgid.link/20260603-parse_iommu_cells-v16-3-dc509dacb19a@oss.qualcomm.com Signed-off-by: Rob Herring (Arm) --- include/linux/of.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'include/linux') 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) { -- cgit v1.2.3