[PATCH 3/4] bsps/riscv: UART - Comment code that queries UART interrupts

[Chris Johns]

On 1/4/19 1:33 am, Hesham Almatary wrote:
> * Different RISC-V DTBs use different names for UART interrupts such as
> "interrupts" and "interrupts-extended", so it is not portable.
> * polling functions are currently used, so there is no need to query interrupts.
> ---
>  bsps/riscv/riscv/console/console-config.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/bsps/riscv/riscv/console/console-config.c b/bsps/riscv/riscv/console/console-config.c
> index 04d0b28361..81e46f304f 100644
> --- a/bsps/riscv/riscv/console/console-config.c
> +++ b/bsps/riscv/riscv/console/console-config.c
> @@ -183,13 +183,20 @@ static void riscv_console_probe(void)
>  
>        ctx->clock = fdt32_to_cpu(val[0]);
>  
> -      val = (fdt32_t *) fdt_getprop(fdt, node, "interrupts", &len);
> +      /* XXX Different RISC-V DTBs use different property names for interrupt
> +      sources. If an interrupt-driven driver is needed, uncomment, replace the
> +      "interrupts-extended" string below with your target's DTB name for UART
> +      interrupts, and use interrupt-driven UART functions instead of
> +      ns16550_polled_* functions */
> +
> +      /* val = (fdt32_t *) fdt_getprop(fdt, node, "interrupts-extended", &len);

Asking a user to edit a BSP complicates a user's ability to configuration manage
and track RTEMS so I prefer we find and use other solutions. For example you
could replace the commented call with a weak function of:

  val = rtems_riscv_get_console_interrupts(fdt, node, &len);

which returns by default "interrupts". A user can then provide a non-weak
version of function and override the default behaviour and return
"interrupts-extended".

A documentation patch for the user manual about this would be nice.

Chris