[PATCH v12 0/3] of: parsing of multi #{iommu,msi}-cells in maps

[PATCH v12 0/3] of: parsing of multi #{iommu,msi}-cells in maps

[Vijayanand Jitta]

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. 

These changes have been tested on QEMU for the arm64 architecture.

Since, this would also need update in dt-schema, raised PR[2] for the
same.

[1] https://lore.kernel.org/all/20250627-video_cb-v3-0-51e18c0ffbce@quicinc.com/
[2] PR for iommu-map dtschema: https://github.com/devicetree-org/dt-schema/pull/184

Robin,

Could this series be pulled into an immutable branch/tag, if it doesn't make
it into the v7.1 merge window? There are client changes dependent on it,
So it would help to get them moving forward rather than waiting another
cycle.

Thanks,
Vijay

V12:
  - Call of_node_put() unconditionally in imx_pcie_add_lut_by_rid()
    thereby addressing comments from Bjorn Helgaas.

  Link to v11:
  https://lore.kernel.org/r/20260325-parse_iommu_cells-v11-0-1fefa5c0e82c@oss.qualcomm.com

V11:
  - Added explicit filter_np parameter to of_map_id() and of_map_msi_id()
    per Dmitry Baryshkov's review feedback, making the filter explicit
    instead of overloading arg->np as both input filter and output parameter.
  - Removed of_node_put() from inside of_map_id(), making the caller responsible
    for reference management. Updated of_msi_xlate() to properly handle reference counting.
  - Collected ACKed by tags, and fixed minor typos.
  Link to v10:
  https://lore.kernel.org/r/20260309-parse_iommu_cells-v10-0-c62fcaa5a1d8@oss.qualcomm.com

V10:
  - Move of_map_iommu_id()/of_map_msi_id() from include/linux/of.h to
    drivers/of/base.c as out-of-line helpers per feedback from Marc Zyngier
    and Rob Herring.
  - Add kernel-doc to document both helpers for discoverability and
    usage clarity.
  - Fix of_map_msi_id() wrapper and all its callers (cdx_msi.c,
    irq-gic-its-msi-parent.c, drivers/of/irq.c) to correctly use the new
    struct of_phandle_args-based API with proper of_node_put() handling
    as per feeback from Dmitry.
  Link to v9:
  https://lore.kernel.org/r/20260301-parse_iommu_cells-v9-0-4d1bceecc5e1@oss.qualcomm.com

V9:
  - Updated TO/CC list based on feedback to include all relevant
    maintainers.
  - No functional changes to the patches themselves.

  Link to V8:
  https://lore.kernel.org/all/20260226074245.3098486-1-vijayanand.jitta@oss.qualcomm.com/

V8:
  - Removed mentions of of_map_args from commit message to match code.

  Link to V7:
  https://lore.kernel.org/all/20260210101157.2145113-1-vijayanand.jitta@oss.qualcomm.com/

V7:
  - Removed of_map_id_args structure and replaced it with
    of_phandle_args as suggested by Dmitry.

  Link to V6:
  https://lore.kernel.org/all/20260121055400.937856-1-vijayanand.jitta@oss.qualcomm.com/

V6:
  - Fixed build error reported by kernel test bot.

  Link to V5:
  https://lore.kernel.org/all/20260118181125.1436036-1-vijayanand.jitta@oss.qualcomm.com/

V5:
  - Fixed Build Warnings.
  - Raised PR for iommu-map dtschema: https://github.com/devicetree-org/dt-schema/pull/184

  Link to V4:
  https://lore.kernel.org/all/20251231114257.2382820-1-vijayanand.jitta@oss.qualcomm.com/

V4:
  - Added Reviewed-by tag.
  - Resolved warnings reported by kernel test bot, minor code
    reorganization.

  Link to V3:
  https://lore.kernel.org/all/20251221213602.2413124-1-vijayanand.jitta@oss.qualcomm.com/

V3:
  - Added Reviewed-by tag.
  - Updated of_map_id_args struct as a wrapper to of_phandle_args and
    added comment description as suggested by Rob Herring.

  Link to V2:
  https://lore.kernel.org/all/20251204095530.8627-1-vijayanand.jitta@oss.qualcomm.com/

V2:
  - Incorporated the patches from Robin that does the clean implementation.
  - Dropped the patches the were adding multi-map support from this series
    as suggested.

V1:
 https://lore.kernel.org/all/cover.1762235099.git.charan.kalla@oss.qualcomm.com/

RFC:
 https://lore.kernel.org/all/20250928171718.436440-1-charan.kalla@oss.qualcomm.com/#r

Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
---
Charan Teja Kalla (1):
      of: Factor arguments passed to of_map_id() into a struct

Robin Murphy (2):
      of: Add convenience wrappers for of_map_id()
      of: Respect #{iommu,msi}-cells in maps

 drivers/cdx/cdx_msi.c                    |   8 +-
 drivers/iommu/of_iommu.c                 |   6 +-
 drivers/irqchip/irq-gic-its-msi-parent.c |  11 +-
 drivers/of/base.c                        | 213 ++++++++++++++++++++++++-------
 drivers/of/irq.c                         |  11 +-
 drivers/pci/controller/dwc/pci-imx6.c    |  34 +++--
 drivers/pci/controller/pcie-apple.c      |   6 +-
 drivers/xen/grant-dma-ops.c              |   5 +-
 include/linux/of.h                       |  30 ++++-
 9 files changed, 240 insertions(+), 84 deletions(-)
---
base-commit: 3fa5e5702a82d259897bd7e209469bc06368bf31
change-id: 20260301-parse_iommu_cells-1c33768aebba

Best regards,
--  
Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>

[PATCH v12 1/3] of: Add convenience wrappers for of_map_id()

[Vijayanand Jitta]

From: Robin Murphy <robin.murphy@arm.com>

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>
Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
---
 drivers/cdx/cdx_msi.c                    |  3 +--
 drivers/iommu/of_iommu.c                 |  4 +---
 drivers/irqchip/irq-gic-its-msi-parent.c |  2 +-
 drivers/of/base.c                        | 38 ++++++++++++++++++++++++++++++++
 drivers/of/irq.c                         |  3 +--
 drivers/pci/controller/dwc/pci-imx6.c    |  6 ++---
 drivers/pci/controller/pcie-apple.c      |  3 +--
 drivers/xen/grant-dma-ops.c              |  3 +--
 include/linux/of.h                       | 18 +++++++++++++++
 9 files changed, 64 insertions(+), 16 deletions(-)

diff --git a/drivers/cdx/cdx_msi.c b/drivers/cdx/cdx_msi.c
index 91b95422b263..63b3544ec997 100644
--- a/drivers/cdx/cdx_msi.c
+++ b/drivers/cdx/cdx_msi.c
@@ -128,8 +128,7 @@ static int cdx_msi_prepare(struct irq_domain *msi_domain,
 	int ret;
 
 	/* Retrieve device ID from requestor ID using parent device */
-	ret = of_map_id(parent->of_node, cdx_dev->msi_dev_id, "msi-map", "msi-map-mask",
-			NULL, &dev_id);
+	ret = of_map_msi_id(parent->of_node, cdx_dev->msi_dev_id, NULL, &dev_id);
 	if (ret) {
 		dev_err(dev, "of_map_id failed for MSI: %d\n", ret);
 		return ret;
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index 6b989a62def2..a511ecf21fcd 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -48,9 +48,7 @@ static int of_iommu_configure_dev_id(struct device_node *master_np,
 	struct of_phandle_args iommu_spec = { .args_count = 1 };
 	int err;
 
-	err = of_map_id(master_np, *id, "iommu-map",
-			 "iommu-map-mask", &iommu_spec.np,
-			 iommu_spec.args);
+	err = of_map_iommu_id(master_np, *id, &iommu_spec.np, iommu_spec.args);
 	if (err)
 		return err;
 
diff --git a/drivers/irqchip/irq-gic-its-msi-parent.c b/drivers/irqchip/irq-gic-its-msi-parent.c
index d36b278ae66c..b63343a227a9 100644
--- a/drivers/irqchip/irq-gic-its-msi-parent.c
+++ b/drivers/irqchip/irq-gic-its-msi-parent.c
@@ -180,7 +180,7 @@ static int of_pmsi_get_msi_info(struct irq_domain *domain, struct device *dev, u
 
 	struct device_node *msi_ctrl __free(device_node) = NULL;
 
-	return of_map_id(dev->of_node, dev->id, "msi-map", "msi-map-mask", &msi_ctrl, dev_id);
+	return of_map_msi_id(dev->of_node, dev->id, &msi_ctrl, dev_id);
 }
 
 static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 57420806c1a2..ae04487bd614 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -2201,3 +2201,41 @@ int of_map_id(const struct device_node *np, u32 id,
 	return 0;
 }
 EXPORT_SYMBOL_GPL(of_map_id);
+
+/**
+ * of_map_iommu_id - Translate an ID using "iommu-map" bindings.
+ * @np: root complex device node.
+ * @id: Requester ID of the device (e.g. PCI RID/BDF or a platform
+ *      stream/device ID) used as the lookup key in the iommu-map table.
+ * @target: optional pointer to a target device node.
+ * @id_out: optional pointer to receive the translated ID.
+ *
+ * Convenience wrapper around of_map_id() using "iommu-map" and "iommu-map-mask".
+ *
+ * Return: 0 on success or a standard error code on failure.
+ */
+int of_map_iommu_id(const struct device_node *np, u32 id,
+		    struct device_node **target, u32 *id_out)
+{
+	return of_map_id(np, id, "iommu-map", "iommu-map-mask", target, id_out);
+}
+EXPORT_SYMBOL_GPL(of_map_iommu_id);
+
+/**
+ * of_map_msi_id - Translate an ID using "msi-map" bindings.
+ * @np: root complex device node.
+ * @id: Requester ID of the device (e.g. PCI RID/BDF or a platform
+ *      stream/device ID) used as the lookup key in the msi-map table.
+ * @target: optional pointer to a target device node.
+ * @id_out: optional pointer to receive the translated ID.
+ *
+ * Convenience wrapper around of_map_id() using "msi-map" and "msi-map-mask".
+ *
+ * Return: 0 on success or a standard error code on failure.
+ */
+int of_map_msi_id(const struct device_node *np, u32 id,
+		  struct device_node **target, u32 *id_out)
+{
+	return of_map_id(np, id, "msi-map", "msi-map-mask", target, id_out);
+}
+EXPORT_SYMBOL_GPL(of_map_msi_id);
diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index 6367c67732d2..e37c1b3f8736 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -817,8 +817,7 @@ u32 of_msi_xlate(struct device *dev, struct device_node **msi_np, u32 id_in)
 	 * "msi-map" or an "msi-parent" property.
 	 */
 	for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) {
-		if (!of_map_id(parent_dev->of_node, id_in, "msi-map",
-				"msi-map-mask", msi_np, &id_out))
+		if (!of_map_msi_id(parent_dev->of_node, id_in, msi_np, &id_out))
 			break;
 		if (!of_check_msi_parent(parent_dev->of_node, msi_np))
 			break;
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index a5b8d0b71677..bff8289f804a 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -1144,8 +1144,7 @@ static int imx_pcie_add_lut_by_rid(struct imx_pcie *imx_pcie, u32 rid)
 	u32 sid = 0;
 
 	target = NULL;
-	err_i = of_map_id(dev->of_node, rid, "iommu-map", "iommu-map-mask",
-			  &target, &sid_i);
+	err_i = of_map_iommu_id(dev->of_node, rid, &target, &sid_i);
 	if (target) {
 		of_node_put(target);
 	} else {
@@ -1158,8 +1157,7 @@ static int imx_pcie_add_lut_by_rid(struct imx_pcie *imx_pcie, u32 rid)
 	}
 
 	target = NULL;
-	err_m = of_map_id(dev->of_node, rid, "msi-map", "msi-map-mask",
-			  &target, &sid_m);
+	err_m = of_map_msi_id(dev->of_node, rid, &target, &sid_m);
 
 	/*
 	 *   err_m      target
diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c
index 2d92fc79f6dd..a0937b7b3c4d 100644
--- a/drivers/pci/controller/pcie-apple.c
+++ b/drivers/pci/controller/pcie-apple.c
@@ -764,8 +764,7 @@ static int apple_pcie_enable_device(struct pci_host_bridge *bridge, struct pci_d
 	dev_dbg(&pdev->dev, "added to bus %s, index %d\n",
 		pci_name(pdev->bus->self), port->idx);
 
-	err = of_map_id(port->pcie->dev->of_node, rid, "iommu-map",
-			"iommu-map-mask", NULL, &sid);
+	err = of_map_iommu_id(port->pcie->dev->of_node, rid, NULL, &sid);
 	if (err)
 		return err;
 
diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c
index c2603e700178..1b7696b2d762 100644
--- a/drivers/xen/grant-dma-ops.c
+++ b/drivers/xen/grant-dma-ops.c
@@ -325,8 +325,7 @@ static int xen_dt_grant_init_backend_domid(struct device *dev,
 		struct pci_dev *pdev = to_pci_dev(dev);
 		u32 rid = PCI_DEVID(pdev->bus->number, pdev->devfn);
 
-		if (of_map_id(np, rid, "iommu-map", "iommu-map-mask", &iommu_spec.np,
-				iommu_spec.args)) {
+		if (of_map_iommu_id(np, rid, &iommu_spec.np, iommu_spec.args)) {
 			dev_dbg(dev, "Cannot translate ID\n");
 			return -ESRCH;
 		}
diff --git a/include/linux/of.h b/include/linux/of.h
index be6ec4916adf..fe841f3cc747 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -465,6 +465,12 @@ 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;
@@ -934,6 +940,18 @@ 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;

-- 
2.34.1

[PATCH v12 2/3] of: Factor arguments passed to of_map_id() into a struct

[Vijayanand Jitta]

From: Charan Teja Kalla <charan.kalla@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>
Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
---
 drivers/cdx/cdx_msi.c                    |  7 ++--
 drivers/iommu/of_iommu.c                 |  4 +-
 drivers/irqchip/irq-gic-its-msi-parent.c | 11 ++++--
 drivers/of/base.c                        | 68 +++++++++++++++++---------------
 drivers/of/irq.c                         | 10 ++++-
 drivers/pci/controller/dwc/pci-imx6.c    | 32 +++++++--------
 drivers/pci/controller/pcie-apple.c      |  5 ++-
 drivers/xen/grant-dma-ops.c              |  4 +-
 include/linux/of.h                       | 14 ++++---
 9 files changed, 89 insertions(+), 66 deletions(-)

diff --git a/drivers/cdx/cdx_msi.c b/drivers/cdx/cdx_msi.c
index 63b3544ec997..6924e07c7528 100644
--- a/drivers/cdx/cdx_msi.c
+++ b/drivers/cdx/cdx_msi.c
@@ -121,22 +121,23 @@ static int cdx_msi_prepare(struct irq_domain *msi_domain,
 			   struct device *dev,
 			   int nvec, msi_alloc_info_t *info)
 {
+	struct of_phandle_args msi_spec = {};
 	struct cdx_device *cdx_dev = to_cdx_device(dev);
 	struct device *parent = cdx_dev->cdx->dev;
 	struct msi_domain_info *msi_info;
-	u32 dev_id;
 	int ret;
 
 	/* Retrieve device ID from requestor ID using parent device */
-	ret = of_map_msi_id(parent->of_node, cdx_dev->msi_dev_id, NULL, &dev_id);
+	ret = of_map_msi_id(parent->of_node, cdx_dev->msi_dev_id, NULL, &msi_spec);
 	if (ret) {
 		dev_err(dev, "of_map_id failed for MSI: %d\n", ret);
 		return ret;
 	}
+	of_node_put(msi_spec.np);
 
 #ifdef GENERIC_MSI_DOMAIN_OPS
 	/* Set the device Id to be passed to the GIC-ITS */
-	info->scratchpad[0].ul = dev_id;
+	info->scratchpad[0].ul = msi_spec.args[0];
 #endif
 
 	msi_info = msi_get_domain_info(msi_domain->parent);
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index a511ecf21fcd..a18bb60f6f3d 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -45,10 +45,10 @@ static int of_iommu_configure_dev_id(struct device_node *master_np,
 				     struct device *dev,
 				     const u32 *id)
 {
-	struct of_phandle_args iommu_spec = { .args_count = 1 };
+	struct of_phandle_args iommu_spec = {};
 	int err;
 
-	err = of_map_iommu_id(master_np, *id, &iommu_spec.np, iommu_spec.args);
+	err = of_map_iommu_id(master_np, *id, &iommu_spec);
 	if (err)
 		return err;
 
diff --git a/drivers/irqchip/irq-gic-its-msi-parent.c b/drivers/irqchip/irq-gic-its-msi-parent.c
index b63343a227a9..dd5f84b6470a 100644
--- a/drivers/irqchip/irq-gic-its-msi-parent.c
+++ b/drivers/irqchip/irq-gic-its-msi-parent.c
@@ -152,6 +152,8 @@ static int its_v5_pci_msi_prepare(struct irq_domain *domain, struct device *dev,
 static int of_pmsi_get_msi_info(struct irq_domain *domain, struct device *dev, u32 *dev_id,
 				phys_addr_t *pa)
 {
+	struct device_node *msi_ctrl __free(device_node) = NULL;
+	struct of_phandle_args msi_spec = {};
 	struct of_phandle_iterator it;
 	int ret;
 
@@ -178,9 +180,12 @@ static int of_pmsi_get_msi_info(struct irq_domain *domain, struct device *dev, u
 		}
 	}
 
-	struct device_node *msi_ctrl __free(device_node) = NULL;
-
-	return of_map_msi_id(dev->of_node, dev->id, &msi_ctrl, dev_id);
+	ret = of_map_msi_id(dev->of_node, dev->id, NULL, &msi_spec);
+	if (!ret) {
+		msi_ctrl = msi_spec.np;
+		*dev_id = msi_spec.args[0];
+	}
+	return ret;
 }
 
 static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
diff --git a/drivers/of/base.c b/drivers/of/base.c
index ae04487bd614..b3d002015192 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -2102,36 +2102,37 @@ int of_find_last_cache_level(unsigned int cpu)
  * @id: device ID to map.
  * @map_name: property name of the map to use.
  * @map_mask_name: optional property name of the mask to use.
- * @target: optional pointer to a target device node.
- * @id_out: optional pointer to receive the translated ID.
+ * @filter_np: optional device node to filter matches by, or NULL to match any.
+ *	If non-NULL, only map entries targeting this node will be matched.
+ * @arg: pointer to a &struct of_phandle_args for the result. On success,
+ *	@arg->args[0] will contain the translated ID. If a map entry was
+ *	matched, @arg->np will be set to the target node with a reference
+ *	held that the caller must release with of_node_put().
  *
  * Given a device ID, look up the appropriate implementation-defined
  * platform ID and/or the target device which receives transactions on that
- * ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or
- * @id_out may be NULL if only the other is required. If @target points to
- * a non-NULL device node pointer, only entries targeting that node will be
- * matched; if it points to a NULL value, it will receive the device node of
- * the first matching target phandle, with a reference held.
+ * ID, as per the "iommu-map" and "msi-map" bindings.
  *
  * Return: 0 on success or a standard error code on failure.
  */
 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)
+	       const struct device_node *filter_np, struct of_phandle_args *arg)
 {
 	u32 map_mask, masked_id;
 	int map_len;
 	const __be32 *map = NULL;
 
-	if (!np || !map_name || (!target && !id_out))
+	if (!np || !map_name || !arg)
 		return -EINVAL;
 
 	map = of_get_property(np, map_name, &map_len);
 	if (!map) {
-		if (target)
+		if (filter_np)
 			return -ENODEV;
 		/* Otherwise, no map implies no translation */
-		*id_out = id;
+		arg->args[0] = id;
+		arg->args_count = 1;
 		return 0;
 	}
 
@@ -2173,18 +2174,14 @@ int of_map_id(const struct device_node *np, u32 id,
 		if (!phandle_node)
 			return -ENODEV;
 
-		if (target) {
-			if (*target)
-				of_node_put(phandle_node);
-			else
-				*target = phandle_node;
-
-			if (*target != phandle_node)
-				continue;
+		if (filter_np && filter_np != phandle_node) {
+			of_node_put(phandle_node);
+			continue;
 		}
 
-		if (id_out)
-			*id_out = masked_id - id_base + out_base;
+		arg->np = phandle_node;
+		arg->args[0] = masked_id - id_base + out_base;
+		arg->args_count = 1;
 
 		pr_debug("%pOF: %s, using mask %08x, id-base: %08x, out-base: %08x, length: %08x, id: %08x -> %08x\n",
 			np, map_name, map_mask, id_base, out_base,
@@ -2193,11 +2190,11 @@ int of_map_id(const struct device_node *np, u32 id,
 	}
 
 	pr_info("%pOF: no %s translation for id 0x%x on %pOF\n", np, map_name,
-		id, target && *target ? *target : NULL);
+		id, filter_np);
 
 	/* Bypasses translation */
-	if (id_out)
-		*id_out = id;
+	arg->args[0] = id;
+	arg->args_count = 1;
 	return 0;
 }
 EXPORT_SYMBOL_GPL(of_map_id);
@@ -2207,17 +2204,19 @@ EXPORT_SYMBOL_GPL(of_map_id);
  * @np: root complex device node.
  * @id: Requester ID of the device (e.g. PCI RID/BDF or a platform
  *      stream/device ID) used as the lookup key in the iommu-map table.
- * @target: optional pointer to a target device node.
- * @id_out: optional pointer to receive the translated ID.
+ * @arg: pointer to a &struct of_phandle_args for the result. On success,
+ *	@arg->args[0] contains the translated ID. If a map entry was matched,
+ *	@arg->np holds a reference to the target node that the caller must
+ *	release with of_node_put().
  *
  * Convenience wrapper around of_map_id() using "iommu-map" and "iommu-map-mask".
  *
  * Return: 0 on success or a standard error code on failure.
  */
 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 of_map_id(np, id, "iommu-map", "iommu-map-mask", target, id_out);
+	return of_map_id(np, id, "iommu-map", "iommu-map-mask", NULL, arg);
 }
 EXPORT_SYMBOL_GPL(of_map_iommu_id);
 
@@ -2226,16 +2225,21 @@ EXPORT_SYMBOL_GPL(of_map_iommu_id);
  * @np: root complex device node.
  * @id: Requester ID of the device (e.g. PCI RID/BDF or a platform
  *      stream/device ID) used as the lookup key in the msi-map table.
- * @target: optional pointer to a target device node.
- * @id_out: optional pointer to receive the translated ID.
+ * @filter_np: optional MSI controller node to filter matches by, or NULL
+ *	to match any. If non-NULL, only map entries targeting this node will
+ *	be matched.
+ * @arg: pointer to a &struct of_phandle_args for the result. On success,
+ *	@arg->args[0] contains the translated ID. If a map entry was matched,
+ *	@arg->np holds a reference to the target node that the caller must
+ *	release with of_node_put().
  *
  * Convenience wrapper around of_map_id() using "msi-map" and "msi-map-mask".
  *
  * Return: 0 on success or a standard error code on failure.
  */
 int of_map_msi_id(const struct device_node *np, u32 id,
-		  struct device_node **target, u32 *id_out)
+		  const struct device_node *filter_np, struct of_phandle_args *arg)
 {
-	return of_map_id(np, id, "msi-map", "msi-map-mask", target, id_out);
+	return of_map_id(np, id, "msi-map", "msi-map-mask", filter_np, arg);
 }
 EXPORT_SYMBOL_GPL(of_map_msi_id);
diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index e37c1b3f8736..f86a56bd81fc 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -817,8 +817,16 @@ u32 of_msi_xlate(struct device *dev, struct device_node **msi_np, u32 id_in)
 	 * "msi-map" or an "msi-parent" property.
 	 */
 	for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) {
-		if (!of_map_msi_id(parent_dev->of_node, id_in, msi_np, &id_out))
+		struct of_phandle_args msi_spec = {};
+
+		if (!of_map_msi_id(parent_dev->of_node, id_in, *msi_np, &msi_spec)) {
+			id_out = msi_spec.args[0];
+			if (!*msi_np)
+				*msi_np = msi_spec.np;
+			else
+				of_node_put(msi_spec.np);
 			break;
+		}
 		if (!of_check_msi_parent(parent_dev->of_node, msi_np))
 			break;
 	}
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index bff8289f804a..c0544d9c0921 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -1137,30 +1137,32 @@ static void imx_pcie_remove_lut(struct imx_pcie *imx_pcie, u16 rid)
 
 static int imx_pcie_add_lut_by_rid(struct imx_pcie *imx_pcie, u32 rid)
 {
+	struct of_phandle_args iommu_spec = {};
+	struct of_phandle_args msi_spec = {};
 	struct device *dev = imx_pcie->pci->dev;
-	struct device_node *target;
 	u32 sid_i, sid_m;
 	int err_i, err_m;
 	u32 sid = 0;
 
-	target = NULL;
-	err_i = of_map_iommu_id(dev->of_node, rid, &target, &sid_i);
-	if (target) {
-		of_node_put(target);
-	} else {
+	err_i = of_map_iommu_id(dev->of_node, rid, &iommu_spec);
+	if (!err_i)
+		sid_i = iommu_spec.args[0];
+	of_node_put(iommu_spec.np);
+	if (!err_i && !iommu_spec.np) {
 		/*
-		 * "target == NULL && err_i == 0" means RID out of map range.
-		 * Use 1:1 map RID to streamID. Hardware can't support this
-		 * because the streamID is only 6 bits
+		 * "iommu_spec.np == NULL && err_i == 0" means RID out of map
+		 * range. Use 1:1 map RID to streamID. Hardware can't support
+		 * this because the streamID is only 6 bits.
 		 */
 		err_i = -EINVAL;
 	}
 
-	target = NULL;
-	err_m = of_map_msi_id(dev->of_node, rid, &target, &sid_m);
-
+	err_m = of_map_msi_id(dev->of_node, rid, NULL, &msi_spec);
+	if (!err_m)
+		sid_m = msi_spec.args[0];
+	of_node_put(msi_spec.np);
 	/*
-	 *   err_m      target
+	 *   err_m      msi_spec.np
 	 *	0	NULL		RID out of range. Use 1:1 map RID to
 	 *				streamID, Current hardware can't
 	 *				support it, so return -EINVAL.
@@ -1168,10 +1170,8 @@ static int imx_pcie_add_lut_by_rid(struct imx_pcie *imx_pcie, u32 rid)
 	 *	0	!= NULL		Get correct streamID from RID
 	 *	!= 0	!= NULL		Invalid combination
 	 */
-	if (!err_m && !target)
+	if (!err_m && !msi_spec.np)
 		return -EINVAL;
-	else if (target)
-		of_node_put(target); /* Find streamID map entry for RID in msi-map */
 
 	/*
 	 * msi-map        iommu-map
diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c
index a0937b7b3c4d..c2cffc0659f4 100644
--- a/drivers/pci/controller/pcie-apple.c
+++ b/drivers/pci/controller/pcie-apple.c
@@ -755,6 +755,7 @@ static int apple_pcie_enable_device(struct pci_host_bridge *bridge, struct pci_d
 {
 	u32 sid, rid = pci_dev_id(pdev);
 	struct apple_pcie_port *port;
+	struct of_phandle_args iommu_spec = {};
 	int idx, err;
 
 	port = apple_pcie_get_port(pdev);
@@ -764,10 +765,12 @@ static int apple_pcie_enable_device(struct pci_host_bridge *bridge, struct pci_d
 	dev_dbg(&pdev->dev, "added to bus %s, index %d\n",
 		pci_name(pdev->bus->self), port->idx);
 
-	err = of_map_iommu_id(port->pcie->dev->of_node, rid, NULL, &sid);
+	err = of_map_iommu_id(port->pcie->dev->of_node, rid, &iommu_spec);
 	if (err)
 		return err;
 
+	of_node_put(iommu_spec.np);
+	sid = iommu_spec.args[0];
 	mutex_lock(&port->pcie->lock);
 
 	idx = bitmap_find_free_region(port->sid_map, port->sid_map_sz, 0);
diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c
index 1b7696b2d762..2aa1a772a0ff 100644
--- a/drivers/xen/grant-dma-ops.c
+++ b/drivers/xen/grant-dma-ops.c
@@ -319,13 +319,13 @@ static int xen_dt_grant_init_backend_domid(struct device *dev,
 					   struct device_node *np,
 					   domid_t *backend_domid)
 {
-	struct of_phandle_args iommu_spec = { .args_count = 1 };
+	struct of_phandle_args iommu_spec = {};
 
 	if (dev_is_pci(dev)) {
 		struct pci_dev *pdev = to_pci_dev(dev);
 		u32 rid = PCI_DEVID(pdev->bus->number, pdev->devfn);
 
-		if (of_map_iommu_id(np, rid, &iommu_spec.np, iommu_spec.args)) {
+		if (of_map_iommu_id(np, rid, &iommu_spec)) {
 			dev_dbg(dev, "Cannot translate ID\n");
 			return -ESRCH;
 		}
diff --git a/include/linux/of.h b/include/linux/of.h
index fe841f3cc747..8548cd9eb4f1 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -463,13 +463,13 @@ 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);
+	       const struct device_node *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);
+		  const struct device_node *filter_np, struct of_phandle_args *arg);
 
 phys_addr_t of_dma_get_max_cpu_address(struct device_node *np);
 
@@ -935,19 +935,21 @@ 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)
+			     const struct device_node *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)
+				const struct device_node *filter_np,
+				struct of_phandle_args *arg)
 {
 	return -EINVAL;
 }

-- 
2.34.1

[PATCH v12 3/3] of: Respect #{iommu,msi}-cells in maps

[Vijayanand Jitta]

From: Robin Murphy <robin.murphy@arm.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>
Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
---
 drivers/of/base.c  | 155 ++++++++++++++++++++++++++++++++++++++++-------------
 include/linux/of.h |   6 ++-
 2 files changed, 123 insertions(+), 38 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index b3d002015192..7b22e2484e1c 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -2096,18 +2096,48 @@ int of_find_last_cache_level(unsigned int cpu)
 	return cache_level;
 }
 
+/*
+ * Some DTs have an iommu-map targeting a 2-cell IOMMU node while
+ * specifying only 1 cell. Fortunately they all consist of value '1'
+ * as the 2nd cell entry with the same target, so check for that pattern.
+ *
+ * Example:
+ *	IOMMU node:
+ *		#iommu-cells = <2>;
+ *
+ *	Device node:
+ *		iommu-map = <0x0000 &smmu 0x0000 0x1>,
+ *			    <0x0100 &smmu 0x0100 0x1>;
+ */
+static bool of_check_bad_map(const __be32 *map, int len)
+{
+	__be32 phandle = map[1];
+
+	if (len % 4)
+		return false;
+	for (int i = 0; i < len; i += 4) {
+		if (map[i + 1] != phandle || map[i + 3] != cpu_to_be32(1))
+			return false;
+	}
+	return true;
+}
+
 /**
  * of_map_id - Translate an ID through a downstream mapping.
  * @np: root complex device node.
  * @id: device ID to map.
  * @map_name: property name of the map to use.
+ * @cells_name: property name of target specifier cells.
  * @map_mask_name: optional property name of the mask to use.
  * @filter_np: optional device node to filter matches by, or NULL to match any.
  *	If non-NULL, only map entries targeting this node will be matched.
  * @arg: pointer to a &struct of_phandle_args for the result. On success,
- *	@arg->args[0] will contain the translated ID. If a map entry was
- *	matched, @arg->np will be set to the target node with a reference
- *	held that the caller must release with of_node_put().
+ *	@arg->args_count will be set to the number of output specifier cells
+ *	as defined by @cells_name in the target node, and
+ *	@arg->args[0..args_count-1] will contain the translated output
+ *	specifier values. If a map entry was matched, @arg->np will be set
+ *	to the target node with a reference held that the caller must release
+ *	with of_node_put().
  *
  * Given a device ID, look up the appropriate implementation-defined
  * platform ID and/or the target device which receives transactions on that
@@ -2116,17 +2146,19 @@ int of_find_last_cache_level(unsigned int cpu)
  * Return: 0 on success or a standard error code on failure.
  */
 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,
 	       const struct device_node *filter_np, struct of_phandle_args *arg)
 {
 	u32 map_mask, masked_id;
-	int map_len;
+	int map_bytes, map_len, offset = 0;
+	bool bad_map = false;
 	const __be32 *map = NULL;
 
 	if (!np || !map_name || !arg)
 		return -EINVAL;
 
-	map = of_get_property(np, map_name, &map_len);
+	map = of_get_property(np, map_name, &map_bytes);
 	if (!map) {
 		if (filter_np)
 			return -ENODEV;
@@ -2136,11 +2168,9 @@ int of_map_id(const struct device_node *np, u32 id,
 		return 0;
 	}
 
-	if (!map_len || map_len % (4 * sizeof(*map))) {
-		pr_err("%pOF: Error: Bad %s length: %d\n", np,
-			map_name, map_len);
-		return -EINVAL;
-	}
+	if (map_bytes % sizeof(*map))
+		goto err_map_len;
+	map_len = map_bytes / sizeof(*map);
 
 	/* The default is to select all bits. */
 	map_mask = 0xffffffff;
@@ -2153,39 +2183,82 @@ int of_map_id(const struct device_node *np, u32 id,
 		of_property_read_u32(np, map_mask_name, &map_mask);
 
 	masked_id = map_mask & id;
-	for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) {
+
+	while (offset < map_len) {
 		struct device_node *phandle_node;
-		u32 id_base = be32_to_cpup(map + 0);
-		u32 phandle = be32_to_cpup(map + 1);
-		u32 out_base = be32_to_cpup(map + 2);
-		u32 id_len = be32_to_cpup(map + 3);
+		u32 id_base, phandle, id_len, id_off, cells = 0;
+		const __be32 *out_base;
+
+		if (map_len - offset < 2)
+			goto err_map_len;
+
+		id_base = be32_to_cpup(map + offset);
 
 		if (id_base & ~map_mask) {
-			pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores id-base (0x%x)\n",
-				np, map_name, map_name,
-				map_mask, id_base);
+			pr_err("%pOF: Invalid %s translation - %s (0x%x) ignores id-base (0x%x)\n",
+			       np, map_name, map_mask_name, map_mask, id_base);
 			return -EFAULT;
 		}
 
-		if (masked_id < id_base || masked_id >= id_base + id_len)
-			continue;
-
+		phandle = be32_to_cpup(map + offset + 1);
 		phandle_node = of_find_node_by_phandle(phandle);
 		if (!phandle_node)
 			return -ENODEV;
 
+		if (!bad_map && of_property_read_u32(phandle_node, cells_name, &cells)) {
+			pr_err("%pOF: missing %s property\n", phandle_node, cells_name);
+			of_node_put(phandle_node);
+			return -EINVAL;
+		}
+
+		if (map_len - offset < 3 + cells) {
+			of_node_put(phandle_node);
+			goto err_map_len;
+		}
+
+		if (offset == 0 && cells == 2) {
+			bad_map = of_check_bad_map(map, map_len);
+			if (bad_map) {
+				pr_warn_once("%pOF: %s mismatches target %s, assuming extra cell of 0\n",
+					     np, map_name, cells_name);
+				cells = 1;
+			}
+		}
+
+		out_base = map + offset + 2;
+		offset += 3 + cells;
+
+		id_len = be32_to_cpup(map + offset - 1);
+		if (id_len > 1 && cells > 1) {
+			/*
+			 * With 1 output cell we reasonably assume its value
+			 * has a linear relationship to the input; with more,
+			 * we'd need help from the provider to know what to do.
+			 */
+			pr_err("%pOF: Unsupported %s - cannot handle %d-ID range with %d-cell output specifier\n",
+			       np, map_name, id_len, cells);
+			of_node_put(phandle_node);
+			return -EINVAL;
+		}
+		id_off = masked_id - id_base;
+		if (masked_id < id_base || id_off >= id_len) {
+			of_node_put(phandle_node);
+			continue;
+		}
+
 		if (filter_np && filter_np != phandle_node) {
 			of_node_put(phandle_node);
 			continue;
 		}
 
 		arg->np = phandle_node;
-		arg->args[0] = masked_id - id_base + out_base;
-		arg->args_count = 1;
+		for (int i = 0; i < cells; i++)
+			arg->args[i] = id_off + be32_to_cpu(out_base[i]);
+		arg->args_count = cells;
 
 		pr_debug("%pOF: %s, using mask %08x, id-base: %08x, out-base: %08x, length: %08x, id: %08x -> %08x\n",
-			np, map_name, map_mask, id_base, out_base,
-			id_len, id, masked_id - id_base + out_base);
+			np, map_name, map_mask, id_base, be32_to_cpup(out_base),
+			id_len, id, id_off + be32_to_cpup(out_base));
 		return 0;
 	}
 
@@ -2196,6 +2269,10 @@ int of_map_id(const struct device_node *np, u32 id,
 	arg->args[0] = id;
 	arg->args_count = 1;
 	return 0;
+
+err_map_len:
+	pr_err("%pOF: Error: Bad %s length: %d\n", np, map_name, map_bytes);
+	return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(of_map_id);
 
@@ -2205,18 +2282,21 @@ EXPORT_SYMBOL_GPL(of_map_id);
  * @id: Requester ID of the device (e.g. PCI RID/BDF or a platform
  *      stream/device ID) used as the lookup key in the iommu-map table.
  * @arg: pointer to a &struct of_phandle_args for the result. On success,
- *	@arg->args[0] contains the translated ID. If a map entry was matched,
- *	@arg->np holds a reference to the target node that the caller must
- *	release with of_node_put().
+ *	@arg->args_count will be set to the number of output specifier cells
+ *	and @arg->args[0..args_count-1] will contain the translated output
+ *	specifier values. If a map entry was matched, @arg->np holds a
+ *	reference to the target node that the caller must release with
+ *	of_node_put().
  *
- * Convenience wrapper around of_map_id() using "iommu-map" and "iommu-map-mask".
+ * Convenience wrapper around of_map_id() using "iommu-map", "#iommu-cells",
+ * and "iommu-map-mask".
  *
  * Return: 0 on success or a standard error code on failure.
  */
 int of_map_iommu_id(const struct device_node *np, u32 id,
 		    struct of_phandle_args *arg)
 {
-	return of_map_id(np, id, "iommu-map", "iommu-map-mask", NULL, arg);
+	return of_map_id(np, id, "iommu-map", "#iommu-cells", "iommu-map-mask", NULL, arg);
 }
 EXPORT_SYMBOL_GPL(of_map_iommu_id);
 
@@ -2229,17 +2309,20 @@ EXPORT_SYMBOL_GPL(of_map_iommu_id);
  *	to match any. If non-NULL, only map entries targeting this node will
  *	be matched.
  * @arg: pointer to a &struct of_phandle_args for the result. On success,
- *	@arg->args[0] contains the translated ID. If a map entry was matched,
- *	@arg->np holds a reference to the target node that the caller must
- *	release with of_node_put().
+ *	@arg->args_count will be set to the number of output specifier cells
+ *	and @arg->args[0..args_count-1] will contain the translated output
+ *	specifier values. If a map entry was matched, @arg->np holds a
+ *	reference to the target node that the caller must release with
+ *	of_node_put().
  *
- * Convenience wrapper around of_map_id() using "msi-map" and "msi-map-mask".
+ * Convenience wrapper around of_map_id() using "msi-map", "#msi-cells",
+ * and "msi-map-mask".
  *
  * Return: 0 on success or a standard error code on failure.
  */
 int of_map_msi_id(const struct device_node *np, u32 id,
 		  const struct device_node *filter_np, struct of_phandle_args *arg)
 {
-	return of_map_id(np, id, "msi-map", "msi-map-mask", filter_np, arg);
+	return of_map_id(np, id, "msi-map", "#msi-cells", "msi-map-mask", filter_np, arg);
 }
 EXPORT_SYMBOL_GPL(of_map_msi_id);
diff --git a/include/linux/of.h b/include/linux/of.h
index 8548cd9eb4f1..51ac8539f2c3 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -462,7 +462,8 @@ 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,
 	       const struct device_node *filter_np, struct of_phandle_args *arg);
 
 int of_map_iommu_id(const struct device_node *np, u32 id,
@@ -934,7 +935,8 @@ 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,
 			     const struct device_node *filter_np,
 			     struct of_phandle_args *arg)
 {

-- 
2.34.1

Re: [PATCH v12 2/3] of: Factor arguments passed to of_map_id() into a struct

[Frank Li]

On Tue, Mar 31, 2026 at 07:34:47PM +0530, Vijayanand Jitta wrote:
> From: Charan Teja Kalla <charan.kalla@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>
> Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
> ---
>  drivers/cdx/cdx_msi.c                    |  7 ++--
>  drivers/iommu/of_iommu.c                 |  4 +-
>  drivers/irqchip/irq-gic-its-msi-parent.c | 11 ++++--
>  drivers/of/base.c                        | 68 +++++++++++++++++---------------
>  drivers/of/irq.c                         | 10 ++++-
>  drivers/pci/controller/dwc/pci-imx6.c    | 32 +++++++--------
>
> for imx part.
>
> Reviewed-by: Frank Li <Frank.Li@nxp.com>

Re: [PATCH v12 2/3] of: Factor arguments passed to of_map_id() into a struct

[Krzysztof Kozlowski]

On 31/03/2026 16:43, Frank Li wrote:
> On Tue, Mar 31, 2026 at 07:34:47PM +0530, Vijayanand Jitta wrote:
>> From: Charan Teja Kalla <charan.kalla@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>
>> Signed-off-by: Vijayanand Jitta <vijayanand.jitta@oss.qualcomm.com>
>> ---
>>  drivers/cdx/cdx_msi.c                    |  7 ++--
>>  drivers/iommu/of_iommu.c                 |  4 +-
>>  drivers/irqchip/irq-gic-its-msi-parent.c | 11 ++++--
>>  drivers/of/base.c                        | 68 +++++++++++++++++---------------
>>  drivers/of/irq.c                         | 10 ++++-
>>  drivers/pci/controller/dwc/pci-imx6.c    | 32 +++++++--------
>>
>> for imx part.
>>
>> Reviewed-by: Frank Li <Frank.Li@nxp.com>

So that's an Ack. Leaving a Rb tag for a tiny tiny piece of big patch
will give impression that everything is reviewed on v13. And the patch
was not reviewed by you.

If you cannot certify the reviewers statement of oversight then use acked

"For instance, maintainers may use it to signify that they are OK with a
patch landing, but they may not have reviewed it as thoroughly as if a
Reviewed-by: was provided."

"For example, if a patch affects multiple subsystems and has an
Acked-by: from one subsystem maintainer then this usually indicates
acknowledgement of *just the part which affects that maintainer's code.*"


Best regards,
Krzysztof