[PATCH 08/13] irqchip: i8259: Add plat-poll support

From: Jiaxun Yang
Date: Tue Aug 27 2019 - 05:00:11 EST


For some platforms (e.g. Loongson-3), platfrom interrupt controller
supports polling interrupt vector from i8259 automaticly and generating
sepreated interrupt.

Thus we add plat-poll OF property for these platforms and setup sepreated
chained interrupt handler.

Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
---
drivers/irqchip/irq-i8259.c | 47 ++++++++++++++++++++++++++++++++-----
1 file changed, 41 insertions(+), 6 deletions(-)

diff --git a/drivers/irqchip/irq-i8259.c b/drivers/irqchip/irq-i8259.c
index d000870d9b6b..e7a9895f3b2d 100644
--- a/drivers/irqchip/irq-i8259.c
+++ b/drivers/irqchip/irq-i8259.c
@@ -40,6 +40,12 @@ static void mask_and_ack_8259A(struct irq_data *d);
static void init_8259A(int auto_eoi);
static int (*i8259_poll)(void) = i8259_irq;

+struct plat_poll_priv {
+ struct irq_domain *domain;
+ int hwirq;
+};
+static struct plat_poll_priv plat_poll_priv[16];
+
static struct irq_chip i8259A_chip = {
.name = "XT-PIC",
.irq_mask = disable_8259A_irq,
@@ -346,22 +352,51 @@ static void i8259_irq_dispatch(struct irq_desc *desc)
generic_handle_irq(irq);
}

+static void plat_poll_irq_dispatch(struct irq_desc *desc)
+{
+ struct plat_poll_priv *priv = irq_desc_get_handler_data(desc);
+ unsigned int irq;
+
+ irq = irq_linear_revmap(priv->domain, priv->hwirq);
+ generic_handle_irq(irq);
+}
+
int __init i8259_of_init(struct device_node *node, struct device_node *parent)
{
struct irq_domain *domain;
- unsigned int parent_irq;

domain = __init_i8259_irqs(node);

- parent_irq = irq_of_parse_and_map(node, 0);
- if (!parent_irq) {
- pr_err("Failed to map i8259 parent IRQ\n");
- irq_domain_remove(domain);
- return -ENODEV;
+ if (of_find_property(node, "plat-poll", NULL)) {
+ int i;
+
+ for (i = 0; i < 16; i++) {
+ int parent_irq = irq_of_parse_and_map(node, i);
+
+ if (!parent_irq) {
+ pr_err("Failed to map %d plat-poll i8259 parent IRQ\n", i);
+ irq_domain_remove(domain);
+ return -ENODEV;
+ }
+ plat_poll_priv[i].domain = domain;
+ plat_poll_priv[i].hwirq = i;
+ irq_set_chained_handler_and_data(parent_irq,
+ plat_poll_irq_dispatch,
+ &plat_poll_priv[i]);
+ }
+ } else {
+ unsigned int parent_irq;
+
+ parent_irq = irq_of_parse_and_map(node, 0);
+ if (!parent_irq) {
+ pr_err("Failed to map i8259 parent IRQ\n");
+ irq_domain_remove(domain);
+ return -ENODEV;
}

irq_set_chained_handler_and_data(parent_irq, i8259_irq_dispatch,
domain);
+ }
return 0;
}
IRQCHIP_DECLARE(i8259, "intel,i8259", i8259_of_init);
--
2.22.0