core: dt_driver: factorize DT phandle util resources

Move struct clk_dt_phandle_args and struct clk_dt_provider from clk_dt.h
to dt_driver.h and rename them to struct dt_driver_phandle_args and
struct dt_driver_provider.

Introduce type get_of_device_func for callback functions used to
retrieve a device instance reference from a DT phandle possible with
arguments.

Acked-by: Jerome Forissier <jerome@forissier.org>
Acked-by: Clément Léger <clement.leger@bootlin.com>
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>

5 files changed, 106 insertions, 51 deletions

diff --git a/core/drivers/clk/clk_dt.c b/core/drivers/clk/clk_dt.c
index 3549b61e..1941531d 100644
--- a/core/drivers/clk/clk_dt.c
+++ b/core/drivers/clk/clk_dt.c
@@ -8,22 +8,11 @@
 #include <drivers/clk_dt.h>
 #include <initcall.h>
 #include <kernel/boot.h>
+#include <kernel/dt_driver.h>
 #include <kernel/panic.h>
 #include <libfdt.h>
 #include <stddef.h>
 
-struct clk_dt_provider {
-	int nodeoffset;
-	unsigned int clock_cells;
-	uint32_t phandle;
-	clk_dt_get_func get_dt_clk;
-	void *data;
-	SLIST_ENTRY(clk_dt_provider) link;
-};
-
-static SLIST_HEAD(, clk_dt_provider) clk_dt_provider_list =
-				SLIST_HEAD_INITIALIZER(clk_dt_provider_list);
-
 static int fdt_clock_cells(const void *fdt, int nodeoffset)
 {
 	const fdt32_t *c = NULL;
@@ -42,36 +31,36 @@ static int fdt_clock_cells(const void *fdt, int nodeoffset)
 TEE_Result clk_dt_register_clk_provider(const void *fdt, int nodeoffset,
 					clk_dt_get_func get_dt_clk, void *data)
 {
-	struct clk_dt_provider *prv = NULL;
+	struct dt_driver_provider *prv = NULL;
 	int clock_cells = 0;
 
 	prv = calloc(1, sizeof(*prv));
 	if (!prv)
 		return TEE_ERROR_OUT_OF_MEMORY;
 
-	prv->get_dt_clk = get_dt_clk;
-	prv->data = data;
+	prv->get_of_device = (get_of_device_func)get_dt_clk;
+	prv->priv_data = data;
 	prv->nodeoffset = nodeoffset;
 	clock_cells = fdt_clock_cells(fdt, nodeoffset);
 	if (clock_cells < 0) {
 		free(prv);
 		return TEE_ERROR_GENERIC;
 	}
-	prv->clock_cells = clock_cells;
+	prv->provider_cells = clock_cells;
 	prv->phandle = fdt_get_phandle(fdt, nodeoffset);
 
-	SLIST_INSERT_HEAD(&clk_dt_provider_list, prv, link);
+	SLIST_INSERT_HEAD(&dt_driver_provider_list, prv, link);
 
 	return TEE_SUCCESS;
 }
 
 static TEE_Result clk_dt_release_provider(void)
 {
-	struct clk_dt_provider *prv = NULL;
+	struct dt_driver_provider *prv = NULL;
 
-	while (!SLIST_EMPTY(&clk_dt_provider_list)) {
-		prv = SLIST_FIRST(&clk_dt_provider_list);
-		SLIST_REMOVE_HEAD(&clk_dt_provider_list, link);
+	while (!SLIST_EMPTY(&dt_driver_provider_list)) {
+		prv = SLIST_FIRST(&dt_driver_provider_list);
+		SLIST_REMOVE_HEAD(&dt_driver_provider_list, link);
 		free(prv);
 	}
 
@@ -80,46 +69,48 @@ static TEE_Result clk_dt_release_provider(void)
 
 driver_init_late(clk_dt_release_provider);
 
-static struct clk_dt_provider *clk_get_provider_by_node(int nodeoffset)
+static struct dt_driver_provider *clk_get_provider_by_node(int nodeoffset)
 {
-	struct clk_dt_provider *prv = NULL;
+	struct dt_driver_provider *prv = NULL;
 
-	SLIST_FOREACH(prv, &clk_dt_provider_list, link)
+	SLIST_FOREACH(prv, &dt_driver_provider_list, link)
 		if (prv->nodeoffset == nodeoffset)
 			return prv;
 
 	return NULL;
 }
 
-static struct clk_dt_provider *clk_get_provider_by_phandle(uint32_t phandle)
+static struct dt_driver_provider *clk_get_provider_by_phandle(uint32_t phandle)
 {
-	struct clk_dt_provider *prv = NULL;
+	struct dt_driver_provider *prv = NULL;
 
-	SLIST_FOREACH(prv, &clk_dt_provider_list, link)
+	SLIST_FOREACH(prv, &dt_driver_provider_list, link)
 		if (prv->phandle == phandle)
 			return prv;
 
 	return NULL;
 }
 
-static struct clk *clk_dt_get_from_provider(struct clk_dt_provider *prv,
+static struct clk *clk_dt_get_from_provider(struct dt_driver_provider *prv,
 					    unsigned int clock_cells,
 					    const uint32_t *prop)
 {
 	unsigned int arg = 0;
 	struct clk *clk = NULL;
-	struct clk_dt_phandle_args pargs = { };
+	struct dt_driver_phandle_args *pargs = NULL;
 
-	pargs.args_count = clock_cells;
-	pargs.args = calloc(pargs.args_count, sizeof(uint32_t));
-	if (!pargs.args)
+	pargs = calloc(1, clock_cells * sizeof(uint32_t *) +
+		       sizeof(*pargs));
+	if (!pargs)
 		return NULL;
 
+	pargs->args_count = clock_cells;
 	for (arg = 0; arg < clock_cells; arg++)
-		pargs.args[arg] = fdt32_to_cpu(prop[arg + 1]);
+		pargs->args[arg] = fdt32_to_cpu(prop[arg + 1]);
+
+	clk = prv->get_of_device(pargs, prv->priv_data);
 
-	clk = prv->get_dt_clk(&pargs, prv->data);
-	free(pargs.args);
+	free(pargs);
 
 	return clk;
 }
@@ -146,7 +137,7 @@ static struct clk *clk_dt_get_by_idx_prop(const char *prop_name,
 	int clock_cells = 0;
 	uint32_t phandle = 0;
 	const uint32_t *prop = NULL;
-	struct clk_dt_provider *prv = NULL;
+	struct dt_driver_provider *prv = NULL;
 
 	prop = fdt_getprop(fdt, nodeoffset, prop_name, &len);
 	if (!prop)
@@ -160,7 +151,7 @@ static struct clk *clk_dt_get_by_idx_prop(const char *prop_name,
 		if (!prv)
 			return NULL;
 
-		clock_cells = prv->clock_cells;
+		clock_cells = prv->provider_cells;
 		if (clk_idx) {
 			clk_idx--;
 			idx += sizeof(phandle) + clock_cells * sizeof(uint32_t);
diff --git a/core/include/drivers/clk_dt.h b/core/include/drivers/clk_dt.h
index 60396990..34ef51be 100644
--- a/core/include/drivers/clk_dt.h
+++ b/core/include/drivers/clk_dt.h
@@ -7,22 +7,11 @@
 #define __DRIVERS_CLK_DT_H
 
 #include <kernel/dt.h>
+#include <kernel/dt_driver.h>
 #include <stdint.h>
 #include <sys/queue.h>
 
 /**
- * struct clk_dt_phandle_args - Devicetree clock args
- * @nodeoffset: Clock consumer node offset
- * @args_count: Count of items in @args
- * @args: Clocks consumer specifiers
- */
-struct clk_dt_phandle_args {
-	int nodeoffset;
-	int args_count;
-	uint32_t *args;
-};
-
-/**
  * struct clk_driver - Clock driver setup struct
  * probe: probe function for the clock driver
  */
@@ -85,7 +74,7 @@ struct clk *clk_dt_get_by_name(const void *fdt, int nodeoffset,
  * Returns a clk struct pointer pointing to a clock matching the devicetree
  * description or NULL if invalid description.
  */
-typedef struct clk *(*clk_dt_get_func)(struct clk_dt_phandle_args *args,
+typedef struct clk *(*clk_dt_get_func)(struct dt_driver_phandle_args *args,
 				       void *data);
 
 /**
@@ -105,7 +94,7 @@ TEE_Result clk_dt_register_clk_provider(const void *fdt, int nodeoffset,
  * providers
  */
 static inline
-struct clk *clk_dt_get_simple_clk(struct clk_dt_phandle_args *args __unused,
+struct clk *clk_dt_get_simple_clk(struct dt_driver_phandle_args *args __unused,
 				  void *data)
 {
 	return data;
diff --git a/core/include/kernel/dt_driver.h b/core/include/kernel/dt_driver.h
new file mode 100644
index 00000000..e011ce99
--- /dev/null
+++ b/core/include/kernel/dt_driver.h
@@ -0,0 +1,63 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/*
+ * Copyright (c) 2021, Linaro Limited
+ * Copyright (c) 2021, Bootlin
+ */
+
+#ifndef __DT_DRIVER_H
+#define __DT_DRIVER_H
+
+#include <kernel/dt.h>
+#include <stdint.h>
+#include <sys/queue.h>
+
+/**
+ * struct dt_driver_phandle_args - Devicetree phandle arguments
+ * @args_count: Count of cells for the device
+ * @args: Device consumer specifiers
+ */
+struct dt_driver_phandle_args {
+	int args_count;
+	uint32_t args[];
+};
+
+/*
+ * get_of_device_func - Callback function for returning a driver private
+ *	instance based on a FDT phandle with possible arguments and the
+ *	registered dt_driver private data reference.
+ *
+ * @parg: phandle argument(s) referencing the device in the FDT.
+ * @data: driver private data registered in struct dt_driver.
+ *
+ * Return a device opaque reference, e.g. a struct clk pointer for a clock
+ * driver, or NULL if not found.
+ */
+typedef void *(*get_of_device_func)(struct dt_driver_phandle_args *parg,
+				    void *data);
+
+/*
+ * struct dt_driver_provider - DT related info on probed device
+ *
+ * Saves information on the probed device so that device
+ * drivers can get resources from DT phandle and related arguments.
+ *
+ * @nodeoffset: Node offset of device referenced in the FDT
+ * @type: One of DT_DRIVER_* or DT_DRIVER_NOTYPE.
+ * @provider_cells: Cells count in the FDT used by the driver's references
+ * @get_of_device: Function to get driver's device ref from phandle data
+ * @priv_data: Driver private data passed as @get_of_device argument
+ * @link: Reference in DT driver providers list
+ */
+struct dt_driver_provider {
+	int nodeoffset;
+	enum dt_driver_type type;
+	unsigned int provider_cells;
+	uint32_t phandle;
+	get_of_device_func get_of_device;
+	void *priv_data;
+	SLIST_ENTRY(dt_driver_provider) link;
+};
+
+SLIST_HEAD(dt_driver_prov_list, dt_driver_provider);
+extern struct dt_driver_prov_list dt_driver_provider_list;
+#endif /* __DT_DRIVER_H */
diff --git a/core/kernel/dt_driver.c b/core/kernel/dt_driver.c
new file mode 100644
index 00000000..4b08ee45
--- /dev/null
+++ b/core/kernel/dt_driver.c
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: BSD-2-Clause
+/*
+ * Copyright (c) 2021, Linaro Limited
+ * Copyright (c) 2021, Bootlin
+ */
+
+#include <kernel/dt_driver.h>
+#include <sys/queue.h>
+
+struct dt_driver_prov_list dt_driver_provider_list =
+	SLIST_HEAD_INITIALIZER(dt_driver_provider_list);
diff --git a/core/kernel/sub.mk b/core/kernel/sub.mk
index a5dfae22..853883dc 100644
--- a/core/kernel/sub.mk
+++ b/core/kernel/sub.mk
@@ -3,6 +3,7 @@ cflags-remove-asan.c-y += $(cflags_kasan)
 srcs-y += assert.c
 srcs-y += console.c
 srcs-$(CFG_DT) += dt.c
+srcs-$(CFG_DT) += dt_driver.c
 srcs-y += pm.c
 srcs-y += handle.c
 srcs-y += interrupt.c