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

[Guo Ren]

Reviewed-by: Guo Ren <guoren at kernel.org>

On Thu, Jun 30, 2022 at 6:02 PM Samuel Holland <samuel at sholland.org> wrote:
>
> 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 at bp.renesas.com>
> Signed-off-by: Samuel Holland <samuel at sholland.org>
> ---
>
> 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
>


-- 
Best Regards
 Guo Ren

ML: https://lore.kernel.org/linux-csky/