lib: sbi_irqchip: Associate 32-bit unique ID for each irqchip device

Allow locating irqchip device instance using a unique 32-bit ID. This
32-bit unique ID can be set by the irqchip driver at the time of adding
irqchip device.

Signed-off-by: Anup Patel <anup.patel@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260213055342.3124872-8-anup.patel@oss.qualcomm.com
Signed-off-by: Anup Patel <anup@brainfault.org>

include/sbi/sbi_irqchip.h

@@ -21,6 +21,9 @@ struct sbi_irqchip_device {
 	/** Node in the list of irqchip devices */
 	struct sbi_dlist node;
 
+	/** Unique ID of this irqchip */
+	u32 id;
+
 	/** Set of harts targetted by this irqchip */
 	struct sbi_hartmask target_harts;
 
@@ -41,6 +44,9 @@ struct sbi_irqchip_device {
  */
 int sbi_irqchip_process(void);
 
+/** Find an irqchip device based on unique ID */
+struct sbi_irqchip_device *sbi_irqchip_find_device(u32 id);
+
 /** Register an irqchip device to receive callbacks */
 int sbi_irqchip_add_device(struct sbi_irqchip_device *chip);
 

lib/sbi/sbi_irqchip.c

@@ -30,6 +30,18 @@ int sbi_irqchip_process(void)
 	return hd->chip->process_hwirqs(hd->chip);
 }
 
+struct sbi_irqchip_device *sbi_irqchip_find_device(u32 id)
+{
+	struct sbi_irqchip_device *chip;
+
+	sbi_list_for_each_entry(chip, &irqchip_list, node) {
+		if (chip->id == id)
+			return chip;
+	}
+
+	return NULL;
+}
+
 int sbi_irqchip_add_device(struct sbi_irqchip_device *chip)
 {
 	struct sbi_irqchip_hart_data *hd;
@@ -39,6 +51,9 @@ int sbi_irqchip_add_device(struct sbi_irqchip_device *chip)
 	if (!chip || !sbi_hartmask_weight(&chip->target_harts))
 		return SBI_EINVAL;
 
+	if (sbi_irqchip_find_device(chip->id))
+		return SBI_EALREADY;
+
 	if (chip->process_hwirqs) {
 		sbi_hartmask_for_each_hartindex(h, &chip->target_harts) {
 			scratch = sbi_hartindex_to_scratch(h);

lib/utils/irqchip/aplic.c

@@ -306,6 +306,7 @@ int aplic_cold_irqchip_init(struct aplic_data *aplic)
 	}
 
 	/* Register irqchip device */
+	aplic->irqchip.id = aplic->unique_id;
 	rc = sbi_irqchip_add_device(&aplic->irqchip);
 	if (rc)
 		return rc;

lib/utils/irqchip/imsic.c

@@ -391,6 +391,7 @@ int imsic_cold_irqchip_init(struct imsic_data *imsic)
 	}
 
 	/* Register irqchip device */
+	imsic_device.id = imsic->unique_id;
 	sbi_hartmask_set_all(&imsic_device.target_harts);
 	rc = sbi_irqchip_add_device(&imsic_device);
 	if (rc)

lib/utils/irqchip/plic.c

@@ -280,6 +280,7 @@ int plic_cold_irqchip_init(struct plic_data *plic)
 	}
 
 	/* Register irqchip device */
+	plic->irqchip.id = plic->unique_id;
 	plic->irqchip.warm_init = plic_warm_irqchip_init;
 	return sbi_irqchip_add_device(&plic->irqchip);
 }