irqchip: GIC: Switch ACPI support to stacked domains

Now that the basic ACPI GSI code is irq domain aware, make sure
that the ACPI support in the GIC doesn't pointlessly deviate from
the DT path.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

2 files changed, 34 insertions, 13 deletions

diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index b41ccf5682c1..ce531e6c1639 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -813,8 +813,6 @@ static int gic_irq_domain_xlate(struct irq_domain *d,
 {
 	unsigned long ret = 0;
 
-	if (irq_domain_get_of_node(d) != controller)
-		return -EINVAL;
 	if (intsize < 3)
 		return -EINVAL;
 
@@ -887,7 +885,7 @@ void gic_set_irqchip_flags(unsigned long flags)
 
 void __init gic_init_bases(unsigned int gic_nr, int irq_start,
 			   void __iomem *dist_base, void __iomem *cpu_base,
-			   u32 percpu_offset, struct device_node *node)
+			   u32 percpu_offset, void *domain_token)
 {
 	irq_hw_number_t hwirq_base;
 	struct gic_chip_data *gic;
@@ -946,8 +944,8 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start,
 		gic_irqs = 1020;
 	gic->gic_irqs = gic_irqs;
 
-	if (node) {		/* DT case */
-		gic->domain = irq_domain_add_linear(node, gic_irqs,
+	if (domain_token) {		/* DT/ACPI case */
+		gic->domain = irq_domain_add_linear(domain_token, gic_irqs,
 						    &gic_irq_domain_hierarchy_ops,
 						    gic);
 	} else {		/* Non-DT case */
@@ -973,7 +971,7 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start,
 			irq_base = irq_start;
 		}
 
-		gic->domain = irq_domain_add_legacy(node, gic_irqs, irq_base,
+		gic->domain = irq_domain_add_legacy(NULL, gic_irqs, irq_base,
 					hwirq_base, &gic_irq_domain_ops, gic);
 	}
 
@@ -1086,6 +1084,31 @@ gic_acpi_parse_madt_distributor(struct acpi_subtable_header *header,
 	return 0;
 }
 
+static int gic_acpi_gsi_desc_populate(struct acpi_gsi_descriptor *data,
+				      u32 gsi, unsigned int irq_type)
+{
+	/*
+	 * Encode GSI and triggering information the way the GIC likes
+	 * them.
+	 */
+	if (WARN_ON(gsi < 16))
+		return -EINVAL;
+
+	if (gsi >= 32) {
+		data->param[0] = 0;		/* SPI */
+		data->param[1] = gsi - 32;
+		data->param[2] = irq_type;
+	} else {
+		data->param[0] = 1; 		/* PPI */
+		data->param[1] = gsi - 16;
+		data->param[2] = 0xff << 4 | irq_type;
+	}
+
+	data->param_count = 3;
+
+	return 0;
+}
+
 int __init
 gic_v2_acpi_init(struct acpi_table_header *table)
 {
@@ -1132,14 +1155,12 @@ gic_v2_acpi_init(struct acpi_table_header *table)
 	}
 
 	/*
-	 * Initialize zero GIC instance (no multi-GIC support). Also, set GIC
-	 * as default IRQ domain to allow for GSI registration and GSI to IRQ
-	 * number translation (see acpi_register_gsi() and acpi_gsi_to_irq()).
+	 * Initialize zero GIC instance (no multi-GIC support).
 	 */
-	gic_init_bases(0, -1, dist_base, cpu_base, 0, NULL);
-	irq_set_default_host(gic_data[0].domain);
+	gic_init_bases(0, -1, dist_base, cpu_base, 0, (void *)ACPI_IRQ_MODEL_GIC);
 
-	acpi_irq_model = ACPI_IRQ_MODEL_GIC;
+	acpi_set_irq_model(ACPI_IRQ_MODEL_GIC, ACPI_IRQ_MODEL_GIC,
+			   gic_acpi_gsi_desc_populate);
 	return 0;
 }
 #endif
diff --git a/include/linux/irqchip/arm-gic.h b/include/linux/irqchip/arm-gic.h
index 9de976b4f9a7..97799b76d7a4 100644
--- a/include/linux/irqchip/arm-gic.h
+++ b/include/linux/irqchip/arm-gic.h
@@ -97,7 +97,7 @@ struct device_node;
 
 void gic_set_irqchip_flags(unsigned long flags);
 void gic_init_bases(unsigned int, int, void __iomem *, void __iomem *,
-		    u32 offset, struct device_node *);
+		    u32 offset, void *);
 void gic_cascade_irq(unsigned int gic_nr, unsigned int irq);
 void gic_cpu_if_down(void);