On 13.07.2023 11:30, Oleksii Kurochko wrote:
> --- a/xen/drivers/char/ns16550.c
> +++ b/xen/drivers/char/ns16550.c
> @@ -1791,8 +1791,16 @@ static int __init ns16550_uart_dt_init(struct
> dt_device_node *dev,
> }
>
> res = platform_get_irq(dev, 0);
> - if ( ! res )
> - return -EINVAL;
> + if ( res == -1 )
> + {
> + printk("ns1650: polling will be used\n");
Nit: Please don't omit one of the two 5-s here.
> + /*
> + * There is the check 'if ( uart->irq > 0 )' in
> ns16550_init_postirq().
> + * If the check is true then interrupt mode will be used otherwise
> + * ( when irq = 0 )polling.
> + */
I wonder in how far that's actually correct outside of x86. On x86 IRQ0 is
always the timer interrupt, but I'm not convinced something similar can be
used as kind of a heuristic on Arm, RISC-V, or basically any other
architecture.
Jan
