[PATCH v4 2/4] of/irq: Add new function of_msi_map_rid()

[David Daney]

From: David Daney 

The device tree property "msi-map" specifies how to create the PCI
requester id used in some MSI controllers.  Add a new function
of_msi_map_rid() that finds the msi-map property and applies its
translation to a given requester id.

Reviewed-by: Marc Zyngier 
Acked-by: Rob Herring 
Signed-off-by: David Daney 
---
 drivers/of/irq.c   | 84 ++
 include/linux/of_irq.h |  7 +
 2 files changed, 91 insertions(+)

diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index 55317fa..c90bd4e 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -598,3 +598,87 @@ void of_msi_configure(struct device *dev, struct 
device_node *np)
d = irq_find_host(msi_np);
dev_set_msi_domain(dev, d);
 }
+
+/**
+ * of_msi_map_rid - Map a MSI requester ID for a device.
+ * @dev: device for which the mapping is to be done.
+ * @msi_np: device node of the expected msi controller.
+ * @rid_in: unmapped MSI requester ID for the device.
+ *
+ * Walk up the device hierarchy looking for devices with a "msi-map"
+ * property.  If found, apply the mapping to @rid_in.
+ *
+ * Returns the mapped MSI requester ID.
+ */
+u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in)
+{
+   struct device *parent_dev;
+   struct device_node *msi_controller_node;
+   u32 map_mask, masked_rid, rid_base, msi_base, rid_len, phandle;
+   int msi_map_len;
+   bool matched;
+   u32 rid_out = rid_in;
+   const __be32 *msi_map = NULL;
+
+   /*
+* Walk up the device parent links looking for one with a
+* "msi-map" property.
+*/
+   for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) {
+   if (!parent_dev->of_node)
+   continue;
+
+   msi_map = of_get_property(parent_dev->of_node,
+ "msi-map", _map_len);
+   if (!msi_map)
+   continue;
+
+   if (msi_map_len % (4 * sizeof(__be32))) {
+   dev_err(parent_dev, "Error: Bad msi-map length: %d\n",
+   msi_map_len);
+   return rid_out;
+   }
+   /* We have a good parent_dev and msi_map, let's use them. */
+   break;
+   }
+   if (!msi_map)
+   return rid_out;
+
+   /* The default is to select all bits. */
+   map_mask = 0x;
+
+   /*
+* Can be overridden by "msi-map-mask" property.  If
+* of_property_read_u32() fails, the default is used.
+*/
+   of_property_read_u32(parent_dev->of_node, "msi-map-mask", _mask);
+
+   masked_rid = map_mask & rid_in;
+   matched = false;
+   while (!matched && msi_map_len >= 4 * sizeof(__be32)) {
+   rid_base = be32_to_cpup(msi_map + 0);
+   phandle = be32_to_cpup(msi_map + 1);
+   msi_base = be32_to_cpup(msi_map + 2);
+   rid_len = be32_to_cpup(msi_map + 3);
+
+   msi_controller_node = of_find_node_by_phandle(phandle);
+
+   matched = masked_rid >= rid_base &&
+   masked_rid < rid_base + rid_len &&
+   msi_np == msi_controller_node;
+
+   of_node_put(msi_controller_node);
+   msi_map_len -= 4 * sizeof(__be32);
+   msi_map += 4;
+   }
+   if (!matched)
+   return rid_out;
+
+   rid_out = masked_rid + msi_base;
+   dev_dbg(dev,
+   "msi-map at: %s, using mask %08x, rid-base: %08x, msi-base: 
%08x, length: %08x, rid: %08x -> %08x\n",
+   dev_name(parent_dev), map_mask, rid_base, msi_base,
+   rid_len, rid_in, rid_out);
+
+   return rid_out;
+}
diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h
index 4bcbd58..8cd9334 100644
--- a/include/linux/of_irq.h
+++ b/include/linux/of_irq.h
@@ -75,6 +75,7 @@ static inline int of_irq_to_resource_table(struct device_node 
*dev,
 extern unsigned int irq_of_parse_and_map(struct device_node *node, int index);
 extern struct device_node *of_irq_find_parent(struct device_node *child);
 extern void of_msi_configure(struct device *dev, struct device_node *np);
+u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in);
 
 #else /* !CONFIG_OF */
 static inline unsigned int irq_of_parse_and_map(struct device_node *dev,
@@ -87,6 +88,12 @@ static inline void *of_irq_find_parent(struct device_node 
*child)
 {
return NULL;
 }
+
+static inline u32 of_msi_map_rid(struct device *dev,
+struct device_node *msi_np, u32 rid_in)
+{
+   return rid_in;
+}
 #endif /* !CONFIG_OF */
 
 #endif /* __OF_IRQ_H */
-- 
1.9.1

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[PATCH v4 2/4] of/irq: Add new function of_msi_map_rid()

[David Daney]

From: David Daney 

The device tree property "msi-map" specifies how to create the PCI
requester id used in some MSI controllers.  Add a new function
of_msi_map_rid() that finds the msi-map property and applies its
translation to a given requester id.

Reviewed-by: Marc Zyngier 
Acked-by: Rob Herring 
Signed-off-by: David Daney 
---
 drivers/of/irq.c   | 84 ++
 include/linux/of_irq.h |  7 +
 2 files changed, 91 insertions(+)

diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index 55317fa..c90bd4e 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -598,3 +598,87 @@ void of_msi_configure(struct device *dev, struct 
device_node *np)
d = irq_find_host(msi_np);
dev_set_msi_domain(dev, d);
 }
+
+/**
+ * of_msi_map_rid - Map a MSI requester ID for a device.
+ * @dev: device for which the mapping is to be done.
+ * @msi_np: device node of the expected msi controller.
+ * @rid_in: unmapped MSI requester ID for the device.
+ *
+ * Walk up the device hierarchy looking for devices with a "msi-map"
+ * property.  If found, apply the mapping to @rid_in.
+ *
+ * Returns the mapped MSI requester ID.
+ */
+u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in)
+{
+   struct device *parent_dev;
+   struct device_node *msi_controller_node;
+   u32 map_mask, masked_rid, rid_base, msi_base, rid_len, phandle;
+   int msi_map_len;
+   bool matched;
+   u32 rid_out = rid_in;
+   const __be32 *msi_map = NULL;
+
+   /*
+* Walk up the device parent links looking for one with a
+* "msi-map" property.
+*/
+   for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) {
+   if (!parent_dev->of_node)
+   continue;
+
+   msi_map = of_get_property(parent_dev->of_node,
+ "msi-map", _map_len);
+   if (!msi_map)
+   continue;
+
+   if (msi_map_len % (4 * sizeof(__be32))) {
+   dev_err(parent_dev, "Error: Bad msi-map length: %d\n",
+   msi_map_len);
+   return rid_out;
+   }
+   /* We have a good parent_dev and msi_map, let's use them. */
+   break;
+   }
+   if (!msi_map)
+   return rid_out;
+
+   /* The default is to select all bits. */
+   map_mask = 0x;
+
+   /*
+* Can be overridden by "msi-map-mask" property.  If
+* of_property_read_u32() fails, the default is used.
+*/
+   of_property_read_u32(parent_dev->of_node, "msi-map-mask", _mask);
+
+   masked_rid = map_mask & rid_in;
+   matched = false;
+   while (!matched && msi_map_len >= 4 * sizeof(__be32)) {
+   rid_base = be32_to_cpup(msi_map + 0);
+   phandle = be32_to_cpup(msi_map + 1);
+   msi_base = be32_to_cpup(msi_map + 2);
+   rid_len = be32_to_cpup(msi_map + 3);
+
+   msi_controller_node = of_find_node_by_phandle(phandle);
+
+   matched = masked_rid >= rid_base &&
+   masked_rid < rid_base + rid_len &&
+   msi_np == msi_controller_node;
+
+   of_node_put(msi_controller_node);
+   msi_map_len -= 4 * sizeof(__be32);
+   msi_map += 4;
+   }
+   if (!matched)
+   return rid_out;
+
+   rid_out = masked_rid + msi_base;
+   dev_dbg(dev,
+   "msi-map at: %s, using mask %08x, rid-base: %08x, msi-base: 
%08x, length: %08x, rid: %08x -> %08x\n",
+   dev_name(parent_dev), map_mask, rid_base, msi_base,
+   rid_len, rid_in, rid_out);
+
+   return rid_out;
+}
diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h
index 4bcbd58..8cd9334 100644
--- a/include/linux/of_irq.h
+++ b/include/linux/of_irq.h
@@ -75,6 +75,7 @@ static inline int of_irq_to_resource_table(struct device_node 
*dev,
 extern unsigned int irq_of_parse_and_map(struct device_node *node, int index);
 extern struct device_node *of_irq_find_parent(struct device_node *child);
 extern void of_msi_configure(struct device *dev, struct device_node *np);
+u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in);
 
 #else /* !CONFIG_OF */
 static inline unsigned int irq_of_parse_and_map(struct device_node *dev,
@@ -87,6 +88,12 @@ static inline void *of_irq_find_parent(struct device_node 
*child)
 {
return NULL;
 }
+
+static inline u32 of_msi_map_rid(struct device *dev,
+struct device_node *msi_np, u32 rid_in)
+{
+   return rid_in;
+}
 #endif /* !CONFIG_OF */
 
 #endif /* __OF_IRQ_H */
-- 
1.9.1

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