Re: [PATCH v2 2/4] irqchip/gic-v3: Refactor GIC600 limited to 32bit PA erratum handling

[Geert Uytterhoeven]

Hi Marek,

On Fri, 19 Jun 2026 at 00:04, Marek Vasut
<marek.vasut+renesas@xxxxxxxxxxx> wrote:
> The GIC600 implementation is now known to be used on multiple 64-bit
> SoCs, where it has address width for AXI or APB interface configured
> to 32 bit, and it can access only the first 4GiB of physical address
> space.
>
> Rework the handling of the quirk to work around this limitation such
> that new entries can be added purely as new compatible strings, with
> no need to add additional functions or new its_quirk array entries.
>
> Suggested-by: Marc Zyngier <maz@xxxxxxxxxx>
> Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxxxx>

Thanks for your patch!

> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -4890,10 +4890,17 @@ static bool __maybe_unused its_enable_quirk_hip09_162100801(void *data)
>         return true;
>  }
>
> -static bool __maybe_unused its_enable_rk3568002(void *data)
> +static const char * const dma_32bit_impaired_platforms[] = {
> +#ifdef CONFIG_ROCKCHIP_ERRATUM_3568002
> +       "rockchip,rk3566",
> +       "rockchip,rk3568",
> +#endif
> +       NULL,
> +};
> +
> +static bool __maybe_unused its_enable_dma32(void *data)

__maybe_unused can be dropped...

>  {
> -       if (!of_machine_is_compatible("rockchip,rk3566") &&
> -           !of_machine_is_compatible("rockchip,rk3568"))
> +       if (!of_machine_compatible_match(dma_32bit_impaired_platforms))
>                 return false;
>
>         gfp_flags_quirk |= GFP_DMA32;
> @@ -4968,14 +4975,12 @@ static const struct gic_quirk its_quirks[] = {
>                 .property = "dma-noncoherent",
>                 .init   = its_set_non_coherent,
>         },
> -#ifdef CONFIG_ROCKCHIP_ERRATUM_3568002

... as the #ifdef is removed.

>         {
> -               .desc   = "ITS: Rockchip erratum RK3568002",
> +               .desc   = "ITS: Broken GIC600 integration limited to 32bit PA",
>                 .iidr   = 0x0201743b,
>                 .mask   = 0xffffffff,
> -               .init   = its_enable_rk3568002,
> +               .init   = its_enable_dma32,
>         },
> -#endif
>         {
>         }
>  };

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds