core: interrupt: itr_chip may not require configure handler

The configure handler in struct itr_ops is not required for interrupt
providers which consumers only use the DT to get and configure their
interrupts (with interrupt_dt_get_by_*() and interrupt_create_handler()).
Therefore change itr_chip_is_valid() to not enforce its support
but add back that constraint for the interrupt main controller.

Add an itr_chip_dt_only_init() helper function for interrupt
controllers which consumers only use the DT to configure their
interrupt, that is such controllers do not need a configure handler.

itr_chip_is_valid() is not called outside interrupt.c where it is
used in itr_chip_init() and itr_chip_dt_only_init() so make it a local
function.

Signed-off-by: Etienne Carriere <[email protected]>
Reviewed-by: Jens Wiklander <[email protected]>

core/include/kernel/interrupt.h

@@ -59,9 +59,15 @@ struct itr_chip {
  * @raise_sgi	Raise a SGI or NULL if not applicable to that controller
  * @set_affinity Set interrupt/cpu affinity or NULL if not applicable
  *
- * Handlers @enable, @disable, @mask, @unmask and @configure are mandated.
- * Handlers @mask and @unmask have unpaged memory constraints.
- * See itr_chip_is_valid().
+ * Handlers @enable, @disable, @mask and @unmask are mandated. Handlers
+ * @mask and @unmask have unpaged memory constraints. These requirements are
+ * verified by itr_chip_init() and itr_chip_dt_only_init().
+ *
+ * Handler @configure is needed for interrupt providers which do not rely on
+ * DT for consumers interrupt configuration, that is interrupt consumers using
+ * interrupt_configure() or friends (interrupt_add_handler(),
+ * interrupt_add_configure_handler(), interrupt_add_handler_with_chip(),
+ * etc...).
  */
 struct itr_ops {
 	void (*configure)(struct itr_chip *chip, size_t it, uint32_t type,
@@ -124,18 +130,10 @@ struct itr_handler {
 	})
 
 /*
- * Return true only if interrupt chip provides required handlers
- * @chip: Interrupt controller reference
+ * Initialise an interrupt controller handle to be used only with the DT
+ * @chip	Interrupt controller
  */
-static inline bool itr_chip_is_valid(struct itr_chip *chip)
-{
-	return chip && is_unpaged(chip) && chip->ops &&
-	       is_unpaged((void *)chip->ops) &&
-	       chip->ops->mask && is_unpaged(chip->ops->mask) &&
-	       chip->ops->unmask && is_unpaged(chip->ops->unmask) &&
-	       chip->ops->enable && chip->ops->disable &&
-	       chip->ops->configure;
-}
+TEE_Result itr_chip_dt_only_init(struct itr_chip *chip);
 
 /*
  * Initialise an interrupt controller handle

core/kernel/interrupt.c

@@ -22,12 +22,40 @@
 
 static struct itr_chip *itr_main_chip __nex_bss;
 
+static bool itr_chip_is_valid(struct itr_chip *chip)
+{
+	return chip && is_unpaged(chip) && chip->ops &&
+	       is_unpaged((void *)chip->ops) &&
+	       chip->ops->mask && is_unpaged(chip->ops->mask) &&
+	       chip->ops->unmask && is_unpaged(chip->ops->unmask) &&
+	       chip->ops->enable && chip->ops->disable;
+}
+
+static void __itr_chip_init(struct itr_chip *chip)
+{
+	SLIST_INIT(&chip->handlers);
+}
+
 TEE_Result itr_chip_init(struct itr_chip *chip)
+{
+	/*
+	 * Interrupt chips not using only the DT to configure
+	 * consumers interrupts require configure handler.
+	 */
+	if (!itr_chip_is_valid(chip) || !chip->ops->configure)
+		return TEE_ERROR_BAD_PARAMETERS;
+
+	__itr_chip_init(chip);
+
+	return TEE_SUCCESS;
+}
+
+TEE_Result itr_chip_dt_only_init(struct itr_chip *chip)
 {
 	if (!itr_chip_is_valid(chip))
 		return TEE_ERROR_BAD_PARAMETERS;
 
-	SLIST_INIT(&chip->handlers);
+	__itr_chip_init(chip);
 
 	return TEE_SUCCESS;
 }
@@ -105,6 +133,11 @@ void interrupt_call_handlers(struct itr_chip *chip, size_t itr_num)
 TEE_Result interrupt_configure(struct itr_chip *chip, size_t itr_num,
 			       uint32_t type, uint32_t prio)
 {
+	if (!chip->ops->configure) {
+		EMSG("No configure handler in itr_chip %s", chip->name);
+		return TEE_ERROR_NOT_IMPLEMENTED;
+	}
+
 	chip->ops->configure(chip, itr_num, type, prio);
 
 	return TEE_SUCCESS;
@@ -114,6 +147,7 @@ static TEE_Result add_configure_handler(struct itr_handler *hdl,
 					uint32_t type, uint32_t prio,
 					bool configure)
 {
+	TEE_Result res = TEE_ERROR_GENERIC;
 	struct itr_handler *h = NULL;
 
 	assert(hdl && hdl->chip->ops && is_unpaged(hdl) &&
@@ -129,8 +163,11 @@ static TEE_Result add_configure_handler(struct itr_handler *hdl,
 		}
 	}
 
-	if (configure)
-		interrupt_configure(hdl->chip, hdl->it, type, prio);
+	if (configure) {
+		res = interrupt_configure(hdl->chip, hdl->it, type, prio);
+		if (res)
+			return res;
+	}
 
 	SLIST_INSERT_HEAD(&hdl->chip->handlers, hdl, link);