Hi, Jiaxun,
On Tue, Mar 24, 2020 at 11:39 PM Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx> wrote:
>
> The 1.0 version of that controller has a bug that status bit
> of LPC IRQ sometimes doesn't get set correctly.
>
> So we can always blame LPC IRQ when spurious interrupt happens
> at the parent interrupt line which LPC IRQ supposed to route
> to.
>
> Co-developed-by: Huacai Chen <chenhc@xxxxxxxxxx>
> Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
> ---
> drivers/irqchip/irq-loongson-liointc.c | 16 ++++++++++++++--
> 1 file changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/irqchip/irq-loongson-liointc.c b/drivers/irqchip/irq-loongson-liointc.c
> index 8b6d7b8ddaca..d5054e90eab8 100644
> --- a/drivers/irqchip/irq-loongson-liointc.c
> +++ b/drivers/irqchip/irq-loongson-liointc.c
> @@ -32,6 +32,8 @@
>
> #define LIOINTC_SHIFT_INTx 4
>
> +#define LIOINTC_ERRATA_IRQ 10
> +
> struct liointc_handler_data {
> struct liointc_priv *priv;
> u32 parent_int_map;
> @@ -41,6 +43,7 @@ struct liointc_priv {
> struct irq_chip_generic *gc;
> struct liointc_handler_data handler[LIOINTC_NUM_PARENT];
> u8 map_cache[LIOINTC_CHIP_IRQ];
> + bool have_lpc_irq_errata;
Maybe has_lpc_irq_errata?
> };
>
> static void liointc_chained_handle_irq(struct irq_desc *desc)
> @@ -54,8 +57,14 @@ static void liointc_chained_handle_irq(struct irq_desc *desc)
>
> pending = readl(gc->reg_base + LIOINTC_REG_INTC_STATUS);
>
> - if (!pending)
> - spurious_interrupt();
> + if (!pending) {
> + /* Always blame LPC IRQ if we have that bug and LPC IRQ is enabled */
> + if (handler->priv->have_lpc_irq_errata &&
> + (handler->parent_int_map & ~gc->mask_cache & BIT(LIOINTC_ERRATA_IRQ)))
> + pending = BIT(LIOINTC_ERRATA_IRQ);
> + else
> + spurious_interrupt();
> + }
>
> while (pending) {
> int bit = __ffs(pending);
> @@ -164,6 +173,9 @@ int __init liointc_of_init(struct device_node *node,
> goto out_iounmap;
> }
>
> + if (of_device_is_compatible(node, "loongson,liointc-1.0"))
> + priv->have_lpc_irq_errata = true;
> +
> sz = of_property_read_variable_u32_array(node, "loongson,parent_int_map",
> &of_parent_int_map[0], LIOINTC_NUM_PARENT,
> LIOINTC_NUM_PARENT);
> --
> 2.26.0.rc2
>
>
Regards,
Huacai Chen
