Re: [PATCH v3 5/7] irqchip/loongson-liointc: irqchip add 2.0 version

From: Marc Zyngier
Date: Tue Mar 09 2021 - 04:11:21 EST


On Sat, 06 Mar 2021 02:36:31 +0000,
Qing Zhang <zhangqing@xxxxxxxxxxx> wrote:
>
> Add IO interrupt controller support for Loongson 2k1000, different
> from the 3a series is that 2K1000 has 64 interrupt sources, 0-31
> correspond to the device tree liointc0 device node, and the other
> correspond to liointc1 node.
>
> Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
> Signed-off-by: Qing Zhang <zhangqing@xxxxxxxxxxx>
> ---
>
> v2-v3: No change
>
> drivers/irqchip/irq-loongson-liointc.c | 55 +++++++++++++++++++++-----
> 1 file changed, 46 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/irqchip/irq-loongson-liointc.c b/drivers/irqchip/irq-loongson-liointc.c
> index 09b91b81851c..1c3c80f7f9f5 100644
> --- a/drivers/irqchip/irq-loongson-liointc.c
> +++ b/drivers/irqchip/irq-loongson-liointc.c
> @@ -20,6 +20,7 @@
>
> #define LIOINTC_CHIP_IRQ 32
> #define LIOINTC_NUM_PARENT 4
> +#define LIOINTC_NUM_CORES 4
>
> #define LIOINTC_INTC_CHIP_START 0x20
>
> @@ -42,6 +43,7 @@ struct liointc_handler_data {
> struct liointc_priv {
> struct irq_chip_generic *gc;
> struct liointc_handler_data handler[LIOINTC_NUM_PARENT];
> + void __iomem *core_isr[LIOINTC_NUM_CORES];
> u8 map_cache[LIOINTC_CHIP_IRQ];
> bool has_lpc_irq_errata;
> };
> @@ -51,11 +53,12 @@ static void liointc_chained_handle_irq(struct irq_desc *desc)
> struct liointc_handler_data *handler = irq_desc_get_handler_data(desc);
> struct irq_chip *chip = irq_desc_get_chip(desc);
> struct irq_chip_generic *gc = handler->priv->gc;
> + int core = get_ebase_cpunum() % LIOINTC_NUM_CORES;
> u32 pending;
>
> chained_irq_enter(chip, desc);
>
> - pending = readl(gc->reg_base + LIOINTC_REG_INTC_STATUS);
> + pending = readl(handler->priv->core_isr[core]);
>
> if (!pending) {
> /* Always blame LPC IRQ if we have that bug */
> @@ -141,6 +144,15 @@ static void liointc_resume(struct irq_chip_generic *gc)
> }
>
> static const char * const parent_names[] = {"int0", "int1", "int2", "int3"};
> +static const char * const core_reg_names[] = {"isr0", "isr1", "isr2", "isr3"};
> +
> +static void __iomem *liointc_get_reg_byname(struct device_node *node,
> + const char *name)
> +{
> + int index = of_property_match_string(node, "reg-names", name);
> +
> + return of_iomap(node, index);

So if of_property_match_string() returns an error, you feed that error
to of_iomap()? Somehow, I don't think that's a good idea.

> +}
>
> static int __init liointc_of_init(struct device_node *node,
> struct device_node *parent)
> @@ -159,10 +171,28 @@ static int __init liointc_of_init(struct device_node *node,
> if (!priv)
> return -ENOMEM;
>
> - base = of_iomap(node, 0);
> - if (!base) {
> - err = -ENODEV;
> - goto out_free_priv;
> + if (of_device_is_compatible(node, "loongson,liointc-2.0")) {
> + base = liointc_get_reg_byname(node, "main");
> + if (!base) {
> + err = -ENODEV;
> + goto out_free_priv;
> + }
> + for (i = 0; i < LIOINTC_NUM_CORES; i++) {
> + priv->core_isr[i] =
> + liointc_get_reg_byname(node, core_reg_names[i]);

Please write assignments on a single line.

Thanks,

M.

--
Without deviation from the norm, progress is not possible.