From 11a86874c0a76a712d130b0aec2bbd1dbffa759d Mon Sep 17 00:00:00 2001
From: Patrick Rudolph <patrick.rudolph@9elements.com>
Date: Wed, 23 Oct 2024 15:20:03 +0200
Subject: [PATCH] arm: gic-v3-its: Implement of_xlate

Translate IRQs by implementing of_xlate() as required by
irq_get_by_index() to parse interrupt properties.

Map DT interrupts to ARM GIC interrupts as follows:

- Interrupt numbers ID32-ID1019 are used for SPIs
- ID0-ID15 are used for SGIs
- ID16-ID31 are used for PPIs

TEST: Booted on qemu sbsa-ref that has a GICV3.

Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-by: Moritz Fischer <moritzf@google.com>
---
 arch/arm/lib/gic-v3-its.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/arch/arm/lib/gic-v3-its.c b/arch/arm/lib/gic-v3-its.c
index 22fa46a341..58f8bf864f 100644
--- a/arch/arm/lib/gic-v3-its.c
+++ b/arch/arm/lib/gic-v3-its.c
@@ -4,9 +4,11 @@
  */
 #include <cpu_func.h>
 #include <dm.h>
+#include <irq.h>
 #include <asm/gic.h>
 #include <asm/gic-v3.h>
 #include <asm/io.h>
+#include <dt-bindings/interrupt-controller/arm-gic.h>
 #include <linux/bitops.h>
 #include <linux/printk.h>
 #include <linux/sizes.h>
@@ -163,8 +165,30 @@ static const struct udevice_id gic_v3_ids[] = {
 	{}
 };
 
+static int arm_gic_v3_of_xlate(struct irq *irq, struct ofnode_phandle_args *args)
+{
+	if (args->args_count < 3) {
+		log_debug("Invalid args_count: %d\n", args->args_count);
+		return -EINVAL;
+	}
+
+	if (args->args[0] == GIC_SPI)
+		irq->id = args->args[1] + 32;
+	else
+		irq->id = args->args[1] + 16;
+
+	irq->flags = args->args[2];
+
+	return 0;
+}
+
+static const struct irq_ops arm_gic_v3_ops = {
+	.of_xlate		=  arm_gic_v3_of_xlate,
+};
+
 U_BOOT_DRIVER(arm_gic_v3) = {
 	.name		= "gic-v3",
 	.id		= UCLASS_IRQ,
 	.of_match	= gic_v3_ids,
+	.ops		= &arm_gic_v3_ops,
 };
-- 
2.39.5