clk: zynqmp: use structs for clk query responses

The driver retrieves the clock tree by querying the ATF for the clock
names, the clock topology, the parents and other attributes. The driver
needs to unmarshal the responses.

The definition of the fields in the firmware responses to the queries is
inconsistent. Some are specified as a mask, some as a shift, and by the
length of the previous field.

Define C structs for the entire firmware responses to avoid passing
pointers to arrays of an implicit size and make the format of the
responses to the queries obvious.

Signed-off-by: Michael Tretter <[e-mail]>
Reviewed-by: Jolly Shah <[e-mail]>
[[e-mail]: Drop 0 initializers because sparse complains]
Signed-off-by: Stephen Boyd <[e-mail]>

drivers/clk/zynqmp/clk-zynqmp.h

···
 
 #include <linux/firmware/xlnx-zynqmp.h>
 
-/* Clock APIs payload parameters */
-#define CLK_GET_NAME_RESP_LEN				16
-#define CLK_GET_TOPOLOGY_RESP_WORDS			3
-#define CLK_GET_PARENTS_RESP_WORDS			3
-#define CLK_GET_ATTR_RESP_WORDS				1
-
 enum topology_type {
 	TYPE_INVALID,
 	TYPE_MUX,

drivers/clk/zynqmp/clkc.c

···
 #define MAX_NODES			6
 #define MAX_NAME_LEN			50
 
-#define CLK_TYPE_SHIFT			2
-
-#define PM_API_PAYLOAD_LEN		3
-
-#define NA_PARENT			0xFFFFFFFF
-#define DUMMY_PARENT			0xFFFFFFFE
-
-#define CLK_TYPE_FIELD_LEN		4
-#define CLK_TOPOLOGY_NODE_OFFSET	16
-#define NODES_PER_RESP			3
-
-#define CLK_TYPE_FIELD_MASK		0xF
-#define CLK_FLAG_FIELD_MASK		GENMASK(21, 8)
-#define CLK_TYPE_FLAG_FIELD_MASK	GENMASK(31, 24)
-
-#define CLK_PARENTS_ID_LEN		16
-#define CLK_PARENTS_ID_MASK		0xFFFF
-
 /* Flags for parents */
 #define PARENT_CLK_SELF			0
 #define PARENT_CLK_NODE1		1
···
 #define END_OF_PARENTS			1
 #define RESERVED_CLK_NAME		""
 
-#define CLK_VALID_MASK			0x1
-#define NODE_CLASS_SHIFT		26U
-#define NODE_SUBCLASS_SHIFT		20U
-#define NODE_TYPE_SHIFT			14U
-#define NODE_INDEX_SHIFT		0U
+#define CLK_GET_NAME_RESP_LEN		16
+#define CLK_GET_TOPOLOGY_RESP_WORDS	3
+#define CLK_GET_PARENTS_RESP_WORDS	3
+#define CLK_GET_ATTR_RESP_WORDS		1
 
 enum clk_type {
 	CLK_TYPE_OUTPUT,
···
 	struct clock_parent parent[MAX_PARENT];
 	u32 num_parents;
 	u32 clk_id;
+};
+
+struct name_resp {
+	char name[CLK_GET_NAME_RESP_LEN];
+};
+
+struct topology_resp {
+#define CLK_TOPOLOGY_TYPE		GENMASK(3, 0)
+#define CLK_TOPOLOGY_FLAGS		GENMASK(23, 8)
+#define CLK_TOPOLOGY_TYPE_FLAGS		GENMASK(31, 24)
+	u32 topology[CLK_GET_TOPOLOGY_RESP_WORDS];
+};
+
+struct parents_resp {
+#define NA_PARENT			0xFFFFFFFF
+#define DUMMY_PARENT			0xFFFFFFFE
+#define CLK_PARENTS_ID			GENMASK(15, 0)
+#define CLK_PARENTS_FLAGS		GENMASK(31, 16)
+	u32 parents[CLK_GET_PARENTS_RESP_WORDS];
+};
+
+struct attr_resp {
+#define CLK_ATTR_VALID			BIT(0)
+#define CLK_ATTR_TYPE			BIT(2)
+#define CLK_ATTR_NODE_INDEX		GENMASK(13, 0)
+#define CLK_ATTR_NODE_TYPE		GENMASK(19, 14)
+#define CLK_ATTR_NODE_SUBCLASS		GENMASK(25, 20)
+#define CLK_ATTR_NODE_CLASS		GENMASK(31, 26)
+	u32 attr[CLK_GET_ATTR_RESP_WORDS];
 };
 
 static const char clk_type_postfix[][10] = {
···
 /**
  * zynqmp_pm_clock_get_name() - Get the name of clock for given id
  * @clock_id:	ID of the clock to be queried
- * @name:	Name of given clock
+ * @response:	Name of the clock with the given id
  *
  * This function is used to get name of clock specified by given
  * clock ID.
  *
- * Return: Returns 0, in case of error name would be 0
+ * Return: Returns 0
  */
-static int zynqmp_pm_clock_get_name(u32 clock_id, char *name)
+static int zynqmp_pm_clock_get_name(u32 clock_id,
+				    struct name_resp *response)
 {
 	struct zynqmp_pm_query_data qdata = {0};
 	u32 ret_payload[PAYLOAD_ARG_CNT];
···
 	qdata.arg1 = clock_id;
 
 	eemi_ops->query_data(qdata, ret_payload);
-	memcpy(name, ret_payload, CLK_GET_NAME_RESP_LEN);
+	memcpy(response, ret_payload, sizeof(*response));
 
 	return 0;
 }
···
  * zynqmp_pm_clock_get_topology() - Get the topology of clock for given id
  * @clock_id:	ID of the clock to be queried
  * @index:	Node index of clock topology
- * @topology:	Buffer to store nodes in topology and flags
+ * @response:	Buffer used for the topology response
  *
  * This function is used to get topology information for the clock
  * specified by given clock ID.
···
  *
  * Return: 0 on success else error+reason
  */
-static int zynqmp_pm_clock_get_topology(u32 clock_id, u32 index, u32 *topology)
+static int zynqmp_pm_clock_get_topology(u32 clock_id, u32 index,
+					struct topology_resp *response)
 {
 	struct zynqmp_pm_query_data qdata = {0};
 	u32 ret_payload[PAYLOAD_ARG_CNT];
···
 	qdata.arg2 = index;
 
 	ret = eemi_ops->query_data(qdata, ret_payload);
-	memcpy(topology, &ret_payload[1], CLK_GET_TOPOLOGY_RESP_WORDS * 4);
+	memcpy(response, &ret_payload[1], sizeof(*response));
 
 	return ret;
 }
···
  * zynqmp_pm_clock_get_parents() - Get the first 3 parents of clock for given id
  * @clock_id:	Clock ID
  * @index:	Parent index
- * @parents:	3 parents of the given clock
+ * @response:	Parents of the given clock
  *
  * This function is used to get 3 parents for the clock specified by
  * given clock ID.
···
  *
  * Return: 0 on success else error+reason
  */
-static int zynqmp_pm_clock_get_parents(u32 clock_id, u32 index, u32 *parents)
+static int zynqmp_pm_clock_get_parents(u32 clock_id, u32 index,
+				       struct parents_resp *response)
 {
 	struct zynqmp_pm_query_data qdata = {0};
 	u32 ret_payload[PAYLOAD_ARG_CNT];
···
 	qdata.arg2 = index;
 
 	ret = eemi_ops->query_data(qdata, ret_payload);
-	memcpy(parents, &ret_payload[1], CLK_GET_PARENTS_RESP_WORDS * 4);
+	memcpy(response, &ret_payload[1], sizeof(*response));
 
 	return ret;
 }
···
 /**
  * zynqmp_pm_clock_get_attributes() - Get the attributes of clock for given id
  * @clock_id:	Clock ID
- * @attr:	Clock attributes
+ * @response:	Clock attributes response
  *
  * This function is used to get clock's attributes(e.g. valid, clock type, etc).
  *
  * Return: 0 on success else error+reason
  */
-static int zynqmp_pm_clock_get_attributes(u32 clock_id, u32 *attr)
+static int zynqmp_pm_clock_get_attributes(u32 clock_id,
+					  struct attr_resp *response)
 {
 	struct zynqmp_pm_query_data qdata = {0};
 	u32 ret_payload[PAYLOAD_ARG_CNT];
···
 	qdata.arg1 = clock_id;
 
 	ret = eemi_ops->query_data(qdata, ret_payload);
-	memcpy(attr, &ret_payload[1], CLK_GET_ATTR_RESP_WORDS * 4);
+	memcpy(response, &ret_payload[1], sizeof(*response));
 
 	return ret;
 }
···
  * __zynqmp_clock_get_topology() - Get topology data of clock from firmware
  *				   response data
  * @topology:		Clock topology
- * @data:		Clock topology data received from firmware
+ * @response:		Clock topology data received from firmware
  * @nnodes:		Number of nodes
  *
  * Return: 0 on success else error+reason
  */
 static int __zynqmp_clock_get_topology(struct clock_topology *topology,
-				       u32 *data, u32 *nnodes)
+				       struct topology_resp *response,
+				       u32 *nnodes)
 {
 	int i;
+	u32 type;
 
-	for (i = 0; i < PM_API_PAYLOAD_LEN; i++) {
-		if (!(data[i] & CLK_TYPE_FIELD_MASK))
+	for (i = 0; i < ARRAY_SIZE(response->topology); i++) {
+		type = FIELD_GET(CLK_TOPOLOGY_TYPE, response->topology[i]);
+		if (type == TYPE_INVALID)
 			return END_OF_TOPOLOGY_NODE;
-		topology[*nnodes].type = data[i] & CLK_TYPE_FIELD_MASK;
-		topology[*nnodes].flag = FIELD_GET(CLK_FLAG_FIELD_MASK,
-						   data[i]);
+		topology[*nnodes].type = type;
+		topology[*nnodes].flag = FIELD_GET(CLK_TOPOLOGY_FLAGS,
+						   response->topology[i]);
 		topology[*nnodes].type_flag =
-				FIELD_GET(CLK_TYPE_FLAG_FIELD_MASK, data[i]);
+				FIELD_GET(CLK_TOPOLOGY_TYPE_FLAGS,
+					  response->topology[i]);
 		(*nnodes)++;
 	}
 
···
 				     u32 *num_nodes)
 {
 	int j, ret;
-	u32 pm_resp[PM_API_PAYLOAD_LEN] = {0};
+	struct topology_resp response = { };
 
 	*num_nodes = 0;
-	for (j = 0; j <= MAX_NODES; j += 3) {
+	for (j = 0; j <= MAX_NODES; j += ARRAY_SIZE(response.topology)) {
 		ret = zynqmp_pm_clock_get_topology(clock[clk_id].clk_id, j,
-						   pm_resp);
+						   &response);
 		if (ret)
 			return ret;
-		ret = __zynqmp_clock_get_topology(topology, pm_resp, num_nodes);
+		ret = __zynqmp_clock_get_topology(topology, &response,
+						  num_nodes);
 		if (ret == END_OF_TOPOLOGY_NODE)
 			return 0;
 	}
···
  * __zynqmp_clock_get_parents() - Get parents info of clock from firmware
  *				   response data
  * @parents:		Clock parents
- * @data:		Clock parents data received from firmware
+ * @response:		Clock parents data received from firmware
  * @nparent:		Number of parent
  *
  * Return: 0 on success else error+reason
  */
-static int __zynqmp_clock_get_parents(struct clock_parent *parents, u32 *data,
+static int __zynqmp_clock_get_parents(struct clock_parent *parents,
+				      struct parents_resp *response,
 				      u32 *nparent)
 {
 	int i;
 	struct clock_parent *parent;
 
-	for (i = 0; i < PM_API_PAYLOAD_LEN; i++) {
-		if (data[i] == NA_PARENT)
+	for (i = 0; i < ARRAY_SIZE(response->parents); i++) {
+		if (response->parents[i] == NA_PARENT)
 			return END_OF_PARENTS;
 
 		parent = &parents[i];
-		parent->id = data[i] & CLK_PARENTS_ID_MASK;
-		if (data[i] == DUMMY_PARENT) {
+		parent->id = FIELD_GET(CLK_PARENTS_ID, response->parents[i]);
+		if (response->parents[i] == DUMMY_PARENT) {
 			strcpy(parent->name, "dummy_name");
 			parent->flag = 0;
 		} else {
-			parent->flag = data[i] >> CLK_PARENTS_ID_LEN;
+			parent->flag = FIELD_GET(CLK_PARENTS_FLAGS,
+						 response->parents[i]);
 			if (zynqmp_get_clock_name(parent->id, parent->name))
 				continue;
 		}
···
 				    u32 *num_parents)
 {
 	int j = 0, ret;
-	u32 pm_resp[PM_API_PAYLOAD_LEN] = {0};
+	struct parents_resp response = { };
 
 	*num_parents = 0;
 	do {
 		/* Get parents from firmware */
 		ret = zynqmp_pm_clock_get_parents(clock[clk_id].clk_id, j,
-						  pm_resp);
+						  &response);
 		if (ret)
 			return ret;
 
-		ret = __zynqmp_clock_get_parents(&parents[j], pm_resp,
+		ret = __zynqmp_clock_get_parents(&parents[j], &response,
 						 num_parents);
 		if (ret == END_OF_PARENTS)
 			return 0;
-		j += PM_API_PAYLOAD_LEN;
+		j += ARRAY_SIZE(response.parents);
 	} while (*num_parents <= MAX_PARENT);
 
 	return 0;
···
 static void zynqmp_get_clock_info(void)
 {
 	int i, ret;
-	u32 attr, type = 0, nodetype, subclass, class;
+	u32 type = 0;
+	u32 nodetype, subclass, class;
+	struct attr_resp attr;
+	struct name_resp name;
 
 	for (i = 0; i < clock_max_idx; i++) {
 		ret = zynqmp_pm_clock_get_attributes(i, &attr);
 		if (ret)
 			continue;
 
-		clock[i].valid = attr & CLK_VALID_MASK;
-		clock[i].type = ((attr >> CLK_TYPE_SHIFT) & 0x1) ?
-				CLK_TYPE_EXTERNAL : CLK_TYPE_OUTPUT;
-		nodetype = (attr >> NODE_TYPE_SHIFT) & 0x3F;
-		subclass = (attr >> NODE_SUBCLASS_SHIFT) & 0x3F;
-		class = (attr >> NODE_CLASS_SHIFT) & 0x3F;
+		clock[i].valid = FIELD_GET(CLK_ATTR_VALID, attr.attr[0]);
+		clock[i].type = FIELD_GET(CLK_ATTR_TYPE, attr.attr[0]) ?
+			CLK_TYPE_EXTERNAL : CLK_TYPE_OUTPUT;
 
-		clock[i].clk_id = (class << NODE_CLASS_SHIFT) |
-				  (subclass << NODE_SUBCLASS_SHIFT) |
-				  (nodetype << NODE_TYPE_SHIFT) |
-				  (i << NODE_INDEX_SHIFT);
+		nodetype = FIELD_GET(CLK_ATTR_NODE_TYPE, attr.attr[0]);
+		subclass = FIELD_GET(CLK_ATTR_NODE_SUBCLASS, attr.attr[0]);
+		class = FIELD_GET(CLK_ATTR_NODE_CLASS, attr.attr[0]);
 
-		zynqmp_pm_clock_get_name(clock[i].clk_id, clock[i].clk_name);
+		clock[i].clk_id = FIELD_PREP(CLK_ATTR_NODE_CLASS, class) |
+				  FIELD_PREP(CLK_ATTR_NODE_SUBCLASS, subclass) |
+				  FIELD_PREP(CLK_ATTR_NODE_TYPE, nodetype) |
+				  FIELD_PREP(CLK_ATTR_NODE_INDEX, i);
+
+		zynqmp_pm_clock_get_name(clock[i].clk_id, &name);
+		if (!strcmp(name.name, RESERVED_CLK_NAME))
+			continue;
+		strncpy(clock[i].clk_name, name.name, MAX_NAME_LEN);
 	}
 
 	/* Get topology of all clock */