Re: [PATCH 05/15] tools/libs/light: Increase nr_spi to 160

[Anthony PERARD <anthony.perard@xxxxxxxxx>]

On Wed, Apr 24, 2024 at 11:34:39AM +0800, Henry Wang wrote:
> Increase number of spi to 160 i.e. gic_number_lines() for Xilinx ZynqMP - 32.
> This was done to allocate and assign IRQs to a running domain.
> 
> Signed-off-by: Vikram Garhwal <fnu.vikram@xxxxxxxxxx>
> Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxx>
> Signed-off-by: Henry Wang <xin.wang2@xxxxxxx>
> ---
>  tools/libs/light/libxl_arm.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c
> index dd5c9f4917..50dbd0f2a9 100644
> --- a/tools/libs/light/libxl_arm.c
> +++ b/tools/libs/light/libxl_arm.c
> @@ -181,7 +181,8 @@ int libxl__arch_domain_prepare_config(libxl__gc *gc,
>  
>      LOG(DEBUG, "Configure the domain");
>  
> -    config->arch.nr_spis = nr_spis;
> +    /* gic_number_lines() is 192 for Xilinx ZynqMP. min nr_spis = 192 - 32. 
> */
> +    config->arch.nr_spis = MAX(nr_spis, 160);

Is there a way that that Xen or libxl could find out what the minimum
number of SPI needs to be? Are we going to have to increase that minimum
number every time a new platform comes along?

It doesn't appear that libxl is using that `nr_spis` value and it is
probably just given to Xen. So my guess is that Xen could simply take
care of the minimum value, gic_number_lines() seems to be a Xen
function.

Thanks,

-- 
Anthony PERARD