firmware: xilinx: Add support for runtime features

Add support for runtime features by using an IOCTL call. The features
can be enabled or disabled from the firmware as well as the features
can be configured at runtime by querying IOCTL_SET_FEATURE_CONFIG id.
Similarly, the user can get the configured values of features by
querying IOCTL_GET_FEATURE_CONFIG id.

Acked-by: Michal Simek <[e-mail]>
Signed-off-by: Ronak Jain <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/firmware/xilinx/zynqmp.c

···
 }
 
 /**
+ * zynqmp_pm_set_feature_config - PM call to request IOCTL for feature config
+ * @id:         The config ID of the feature to be configured
+ * @value:      The config value of the feature to be configured
+ *
+ * Return:      Returns 0 on success or error value on failure.
+ */
+int zynqmp_pm_set_feature_config(enum pm_feature_config_id id, u32 value)
+{
+	return zynqmp_pm_invoke_fn(PM_IOCTL, 0, IOCTL_SET_FEATURE_CONFIG,
+				   id, value, NULL);
+}
+
+/**
+ * zynqmp_pm_get_feature_config - PM call to get value of configured feature
+ * @id:         The config id of the feature to be queried
+ * @payload:    Returned value array
+ *
+ * Return:      Returns 0 on success or error value on failure.
+ */
+int zynqmp_pm_get_feature_config(enum pm_feature_config_id id,
+				 u32 *payload)
+{
+	return zynqmp_pm_invoke_fn(PM_IOCTL, 0, IOCTL_GET_FEATURE_CONFIG,
+				   id, 0, payload);
+}
+
+/**
  * struct zynqmp_pm_shutdown_scope - Struct for shutdown scope
  * @subtype:	Shutdown subtype
  * @name:	Matching string for scope argument

include/linux/firmware/xlnx-zynqmp.h

···
 	IOCTL_OSPI_MUX_SELECT = 21,
 	/* Register SGI to ATF */
 	IOCTL_REGISTER_SGI = 25,
+	/* Runtime feature configuration */
+	IOCTL_SET_FEATURE_CONFIG = 26,
+	IOCTL_GET_FEATURE_CONFIG = 27,
 };
 
 enum pm_query_id {
···
 	PM_OSPI_MUX_SEL_LINEAR = 1,
 };
 
+enum pm_feature_config_id {
+	PM_FEATURE_INVALID = 0,
+	PM_FEATURE_OVERTEMP_STATUS = 1,
+	PM_FEATURE_OVERTEMP_VALUE = 2,
+	PM_FEATURE_EXTWDT_STATUS = 3,
+	PM_FEATURE_EXTWDT_VALUE = 4,
+};
+
 /**
  * struct zynqmp_pm_query_data - PM query data
  * @qid:	query ID
···
 int zynqmp_pm_register_notifier(const u32 node, const u32 event,
 				const u32 wake, const u32 enable);
 int zynqmp_pm_feature(const u32 api_id);
+int zynqmp_pm_set_feature_config(enum pm_feature_config_id id, u32 value);
+int zynqmp_pm_get_feature_config(enum pm_feature_config_id id, u32 *payload);
 #else
 static inline int zynqmp_pm_get_api_version(u32 *version)
 {
···
 }
 
 static inline int zynqmp_pm_feature(const u32 api_id)
+{
+	return -ENODEV;
+}
+
+static inline int zynqmp_pm_set_feature_config(enum pm_feature_config_id id,
+					       u32 value)
+{
+	return -ENODEV;
+}
+
+static inline int zynqmp_pm_get_feature_config(enum pm_feature_config_id id,
+					       u32 *payload)
 {
 	return -ENODEV;
 }