Merge tag 'interconnect-next-20251120' of https://source.denx.de/u-boot/custodians/u-boot-snapdragon into next

- Qualcomm RPMh cmd_db_read_slave_id() & cmd_db_read_aux_data()
- Initial Interconnect implementation + Qualcomm RPMh support

4 files changed, 295 insertions, 0 deletions

diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index eb6416b5917..36b5d87c304 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -83,6 +83,8 @@ enum uclass_id {
 	UCLASS_I3C,		/* I3C bus */
 	UCLASS_IDE,		/* IDE device */
 	UCLASS_IOMMU,		/* IOMMU */
+	UCLASS_INTERCONNECT,	/* Interconnect */
+	UCLASS_ICC_NODE,	/* Interconnect Node */
 	UCLASS_IRQ,		/* Interrupt controller */
 	UCLASS_KEYBOARD,	/* Keyboard input device */
 	UCLASS_LED,		/* Light-emitting diode (LED) */
diff --git a/include/interconnect-uclass.h b/include/interconnect-uclass.h
new file mode 100644
index 00000000000..d942ddec41b
--- /dev/null
+++ b/include/interconnect-uclass.h
@@ -0,0 +1,136 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2025 Linaro Limited
+ */
+
+#ifndef _INTERCONNECT_UCLASS_H
+#define _INTERCONNECT_UCLASS_H
+
+#include <interconnect.h>
+
+#define icc_units_to_bps(bw)  ((bw) * 1000ULL)
+
+struct udevice;
+
+/**
+ * struct icc_req - constraints that are attached to each node
+ *
+ * @req_node:	entry in list of requests for the particular @node
+ * @node:	the interconnect node to which this constraint applies
+ * @enabled:	indicates whether the path with this request is enabled
+ * @tag:	path tag (optional)
+ * @avg_bw:	an integer describing the average bandwidth in kBps
+ * @peak_bw:	an integer describing the peak bandwidth in kBps
+ */
+struct icc_req {
+	struct hlist_node	req_node;
+	struct icc_node		*node;
+	bool			enabled;
+	u32			tag;
+	u32			avg_bw;
+	u32			peak_bw;
+};
+
+/**
+ * struct icc_path - An interconnect path
+ *
+ * @dev:	Device who requested the path
+ * @num_nodes:	number of nodes (hops) in the path
+ * @reqs:	array of the requests applicable to this path of nodes
+ */
+struct icc_path {
+	struct udevice		*dev;
+	size_t			num_nodes;
+	struct icc_req		reqs[];
+};
+
+/**
+ * struct icc_provider - interconnect provider (controller) entity that might
+ * provide multiple interconnect controls
+ *
+ * @inter_set:		whether inter-provider pairs will be configured with @set
+ * @xlate_num_nodes:	provider-specific nodes counts for mapping nodes from phandle arguments
+ * @xlate_nodes:	provider-specific array for mapping nodes from phandle arguments
+ */
+struct icc_provider {
+	bool			inter_set;
+	unsigned int		xlate_num_nodes;
+	struct icc_node		**xlate_nodes;
+};
+
+/**
+ * struct icc_node - entity that is part of the interconnect topology
+ *
+ * @dev:		points to the interconnect provider of this node
+ * @links:		a list of targets pointing to where we can go next when traversing
+ * @num_links:		number of links to other interconnect nodes
+ * @users:		count of active users
+ * @node_list:		the list entry in the parent provider's "nodes" list
+ * @search_list:	list used when walking the nodes graph
+ * @reverse:		pointer to previous node when walking the nodes graph
+ * @is_traversed:	flag that is used when walking the nodes graph
+ * @req_list:		a list of QoS constraint requests associated with this node
+ * @avg_bw:		aggregated value of average bandwidth requests from all consumers
+ * @peak_bw:		aggregated value of peak bandwidth requests from all consumers
+ * @data:		pointer to private data
+ */
+struct icc_node {
+	struct udevice		*dev;
+	ulong			*links;
+	size_t			num_links;
+	int			users;
+
+	struct list_head	node_list;
+	struct list_head	search_list;
+	struct icc_node		*reverse;
+	u8			is_traversed:1;
+	struct hlist_head	req_list;
+	u32			avg_bw;
+	u32			peak_bw;
+	void			*data;
+};
+
+/**
+ * struct interconnect_ops - Interconnect uclass operations
+ *
+ * @of_xlate:		provider-specific callback for mapping nodes from phandle arguments
+ * @set:		pointer to device specific set operation function
+ * @pre_aggregate:	pointer to device specific function that is called
+ *			before the aggregation begins (optional)
+ * @aggregate:		pointer to device specific aggregate operation function
+ */
+struct interconnect_ops {
+	struct icc_node *(*of_xlate)(struct udevice *dev,
+				     const struct ofnode_phandle_args *args);
+	int (*set)(struct icc_node *src, struct icc_node *dst);
+	void (*pre_aggregate)(struct icc_node *node);
+	int (*aggregate)(struct icc_node *node, u32 tag, u32 avg_bw,
+			 u32 peak_bw, u32 *agg_avg, u32 *agg_peak);
+};
+
+/**
+ * icc_node_create() - create a node
+ *
+ * @dev:	Provider device
+ * @id:		node id, can be a numeric ID or pointer casted to ulong
+ * @name:	node name
+ *
+ * Return: icc_node pointer on success, or ERR_PTR() on error
+ */
+struct icc_node *icc_node_create(struct udevice *dev,
+				 ulong id, const char *name);
+
+/**
+ * icc_link_create() - create a link between two nodes
+ * @node: source node id
+ * @dst_id: destination node id
+ *
+ * Create a link between two nodes. The nodes might belong to different
+ * interconnect providers and the @dst_id node might not exist, the link
+ * will be done at runtime in `icc_path_find()`.
+ *
+ * Return: 0 on success, or an error code otherwise
+ */
+int icc_link_create(struct icc_node *node, const ulong dst_id);
+
+#endif
diff --git a/include/interconnect.h b/include/interconnect.h
new file mode 100644
index 00000000000..11ed30d79d6
--- /dev/null
+++ b/include/interconnect.h
@@ -0,0 +1,155 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2025 Linaro Limited
+ */
+
+#ifndef _INTERCONNECT_H
+#define _INTERCONNECT_H
+
+#include <linux/errno.h>
+
+struct udevice;
+
+/* macros for converting to icc units */
+#define Bps_to_icc(x)	((x) / 1000)
+#define kBps_to_icc(x)	(x)
+#define MBps_to_icc(x)	((x) * 1000)
+#define GBps_to_icc(x)	((x) * 1000 * 1000)
+#define bps_to_icc(x)	(1)
+#define kbps_to_icc(x)	((x) / 8 + ((x) % 8 ? 1 : 0))
+#define Mbps_to_icc(x)	((x) * 1000 / 8)
+#define Gbps_to_icc(x)	((x) * 1000 * 1000 / 8)
+
+struct icc_path;
+
+/**
+ * of_icc_get - Get an Interconnect path from a DT node based on name
+ *
+ * This function will search for a path between two endpoints and return an
+ * icc_path handle on success. Use icc_put() to release constraints when they
+ * are not needed anymore.
+ * If the interconnect API is disabled, NULL is returned and the consumer
+ * drivers will still build. Drivers are free to handle this specifically,
+ * but they don't have to.
+ *
+ * @dev:	The client device.
+ * @name:	Name of the interconnect endpoint pair.
+ * Return:	icc_path pointer on success or ERR_PTR() on error. NULL is returned
+ * when the API is disabled or the "interconnects" DT property is missing.
+ */
+#if CONFIG_IS_ENABLED(INTERCONNECT)
+struct icc_path *of_icc_get(struct udevice *dev, const char *name);
+#else
+static inline
+struct icc_path *of_icc_get(struct udevice *dev, const char *name)
+{
+	return NULL;
+}
+#endif
+
+/**
+ * of_icc_get - Get an Interconnect path from a DT node based on index
+ *
+ * This function will search for a path between two endpoints and return an
+ * icc_path handle on success. Use icc_put() to release constraints when they
+ * are not needed anymore.
+ * If the interconnect API is disabled, NULL is returned and the consumer
+ * drivers will still build. Drivers are free to handle this specifically,
+ * but they don't have to.
+ *
+ * @dev:	The client device.
+ * @idx:	Index of the interconnect endpoint pair.
+ * Return:	icc_path pointer on success or ERR_PTR() on error. NULL is returned
+ * when the API is disabled or the "interconnects" DT property is missing.
+ */
+#if CONFIG_IS_ENABLED(INTERCONNECT)
+struct icc_path *of_icc_get_by_index(struct udevice *dev, int idx);
+#else
+static inline
+struct icc_path *of_icc_get_by_index(struct udevice *dev, int idx)
+{
+	return NULL;
+}
+#endif
+
+/**
+ * icc_put - release the reference to the Interconnect path.
+ *
+ * Use this function to release the constraints on a path when the path is
+ * no longer needed. The constraints will be re-aggregated.
+ *
+ * @path:	An interconnect path
+ * Return: 0 if OK, or a negative error code.
+ */
+#if CONFIG_IS_ENABLED(INTERCONNECT)
+int icc_put(struct icc_path *path);
+#else
+static inline int icc_put(struct icc_path *path)
+{
+	return 0;
+}
+#endif
+
+/**
+ * icc_enable - Enable an Interconnect path.
+ *
+ * This will enable all the endpoints in the path, using the
+ * bandwidth set by the `icc_set_bw()` call. Otherwise a zero
+ * bandwidth will be set. Usually used after a call to `icc_disable()`.
+ *
+ * @path:	An interconnect path
+ * Return: 0 if OK, or a negative error code. -ENOSYS if not implemented.
+ */
+#if CONFIG_IS_ENABLED(INTERCONNECT)
+int icc_enable(struct icc_path *path);
+#else
+static inline int icc_enable(struct icc_path *path)
+{
+	return -ENOSYS;
+}
+#endif
+
+/**
+ * icc_disable - Disable an Interconnect path.
+ *
+ * This will disable all the endpoints in the path, effectively setting
+ * a zero bandwidth. Calling `icc_enable()` will restore the bandwidth set
+ * by calling `icc_set_bw()`.
+ *
+ * @path:	An interconnect path
+ * Return: 0 if OK, or a negative error code. -ENOSYS if not implemented.
+ */
+#if CONFIG_IS_ENABLED(INTERCONNECT)
+int icc_disable(struct icc_path *path);
+#else
+static inline int icc_disable(struct icc_path *path)
+{
+	return -ENOSYS;
+}
+#endif
+
+/**
+ * icc_set_bw - set bandwidth constraints on an interconnect path.
+ *
+ * This function is used by an interconnect consumer to express its own needs
+ * in terms of bandwidth for a previously requested path between two endpoints.
+ * The requests are aggregated and each node is updated accordingly. The entire
+ * path is locked by a mutex to ensure that the set() is completed.
+ * The @path can be NULL when the "interconnects" DT properties is missing,
+ * which will mean that no constraints will be set.
+ *
+ * @path:	An interconnect path
+ * @avg_bw:	Average bandwidth request in kBps
+ * @peak_bw:	Peak bandwidth in request kBps
+ * Return: 0 if OK, or a negative error code. -ENOSYS if not implemented.
+ */
+#if CONFIG_IS_ENABLED(INTERCONNECT)
+int icc_set_bw(struct icc_path *path, u32 avg_bw, u32 peak_bw);
+#else
+static inline int icc_set_bw(struct icc_path *path, u32 avg_bw, u32 peak_bw)
+{
+	return -ENOSYS;
+}
+#endif
+
+#endif
diff --git a/include/soc/qcom/cmd-db.h b/include/soc/qcom/cmd-db.h
index 1190f2c22ca..16609ac9d78 100644
--- a/include/soc/qcom/cmd-db.h
+++ b/include/soc/qcom/cmd-db.h
@@ -21,6 +21,8 @@ enum cmd_db_hw_type {
 
 #if IS_ENABLED(CONFIG_QCOM_COMMAND_DB)
 u32 cmd_db_read_addr(const char *resource_id);
+enum cmd_db_hw_type cmd_db_read_slave_id(const char *resource_id);
+const void *cmd_db_read_aux_data(const char *resource_id, size_t *len);
 
 #else
 static inline u32 cmd_db_read_addr(const char *resource_id)