[PATCH v3 4/4] irqchip/sifive-plic: Fix T-HEAD PLIC edge trigger handling

From: Samuel Holland
Date: Thu Jun 30 2022 - 06:03:11 EST


The T-HEAD PLIC ignores additional edges seen while an edge-triggered
interrupt is being handled. Because of this behavior, the driver needs
to complete edge-triggered interrupts in the .irq_ack callback before
handling them, instead of in the .irq_eoi callback afterward. Otherwise,
it could miss some interrupts.

Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Signed-off-by: Samuel Holland <samuel@xxxxxxxxxxxx>
---

Changes in v3:
- Rebased on top of the RZ/Five patches

drivers/irqchip/irq-sifive-plic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
index 90e44367bee9..b3a36dca7f1b 100644
--- a/drivers/irqchip/irq-sifive-plic.c
+++ b/drivers/irqchip/irq-sifive-plic.c
@@ -474,7 +474,6 @@ static int __init plic_init(struct device_node *node,

IRQCHIP_DECLARE(sifive_plic, "sifive,plic-1.0.0", plic_init);
IRQCHIP_DECLARE(riscv_plic0, "riscv,plic0", plic_init); /* for legacy systems */
-IRQCHIP_DECLARE(thead_c900_plic, "thead,c900-plic", plic_init); /* for firmware driver */

static int __init plic_edge_init(struct device_node *node,
struct device_node *parent)
@@ -483,3 +482,4 @@ static int __init plic_edge_init(struct device_node *node,
}

IRQCHIP_DECLARE(andestech_nceplic100, "andestech,nceplic100", plic_edge_init);
+IRQCHIP_DECLARE(thead_c900_plic, "thead,c900-plic", plic_edge_init);
--
2.35.1