irqchip/loongson-eiointc: Add suspend/resume support

Add suspend/resume support for EIOINTC irqchip, which is needed for
upcoming suspend/hibernation.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221020073527.541845-3-chenhuacai@loongson.cn

diff --git a/drivers/irqchip/irq-loongson-eiointc.c b/drivers/irqchip/irq-loongson-eiointc.c
index 16e9af8d8b1eabb3d9c21223927aefb06a9cc481..5cf4b800e499875f5749e2421e7e710b56300f54 100644 (file)
--- a/drivers/irqchip/irq-loongson-eiointc.c
+++ b/drivers/irqchip/irq-loongson-eiointc.c
@@ -17,6 +17,7 @@
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
+#include <linux/syscore_ops.h>
 
 #define EIOINTC_REG_NODEMAP    0x14a0
 #define EIOINTC_REG_IPMAP      0x14c0
@@ -301,6 +302,37 @@ static struct irq_domain *acpi_get_vec_parent(int node, struct acpi_vector_group
        return NULL;
 }
 
+static int eiointc_suspend(void)
+{
+       return 0;
+}
+
+static void eiointc_resume(void)
+{
+       int i, j;
+       struct irq_desc *desc;
+       struct irq_data *irq_data;
+
+       eiointc_router_init(0);
+
+       for (i = 0; i < nr_pics; i++) {
+               for (j = 0; j < VEC_COUNT; j++) {
+                       desc = irq_resolve_mapping(eiointc_priv[i]->eiointc_domain, j);
+                       if (desc && desc->handle_irq && desc->handle_irq != handle_bad_irq) {
+                               raw_spin_lock(&desc->lock);
+                               irq_data = &desc->irq_data;
+                               eiointc_set_irq_affinity(irq_data, irq_data->common->affinity, 0);
+                               raw_spin_unlock(&desc->lock);
+                       }
+               }
+       }
+}
+
+static struct syscore_ops eiointc_syscore_ops = {
+       .suspend = eiointc_suspend,
+       .resume = eiointc_resume,
+};
+
 static int __init
 pch_pic_parse_madt(union acpi_subtable_headers *header,
                       const unsigned long end)
@@ -380,6 +412,7 @@ int __init eiointc_acpi_init(struct irq_domain *parent,
        parent_irq = irq_create_mapping(parent, acpi_eiointc->cascade);
        irq_set_chained_handler_and_data(parent_irq, eiointc_irq_dispatch, priv);
 
+       register_syscore_ops(&eiointc_syscore_ops);
        cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_LOONGARCH_STARTING,
                                  "irqchip/loongarch/intc:starting",
                                  eiointc_router_init, NULL);