Re: [PATCH v4 11/12] doc/man: update description for nr_spis with eSPI

[Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>]

Hi Leonid,

Leonid Komarianskyi <Leonid_Komarianskyi@xxxxxxxx> writes:

> Since eSPI support has been introduced, update the documentation with
> the appropriate description.
>
> Signed-off-by: Leonid Komarianskyi <leonid_komarianskyi@xxxxxxxx>
>
> ---
> Changes in V4:
> - introduced this patch
> ---
>  docs/man/xl.cfg.5.pod.in | 13 ++++++++-----
>  1 file changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/docs/man/xl.cfg.5.pod.in b/docs/man/xl.cfg.5.pod.in
> index 5362fb0e9a..292ab10331 100644
> --- a/docs/man/xl.cfg.5.pod.in
> +++ b/docs/man/xl.cfg.5.pod.in
> @@ -3072,11 +3072,14 @@ interval of colors (such as "0-4").
>  =item B<nr_spis="NR_SPIS">
>  
>  An optional integer parameter specifying the number of SPIs (Shared
> -Peripheral Interrupts) to allocate for the domain. Max is 960 SPIs. If
> -the `nr_spis` parameter is not specified, the value calculated by the 
> toolstack
> -will be used for the domain. Otherwise, the value specified by the `nr_spis`
> -parameter will be used. The number of SPIs should match the highest interrupt
> -ID that will be assigned to the domain.
> +Peripheral Interrupts) to allocate for the domain. Max is 960 for regular 
> SPIs
> +or 5088 for eSPIs (Extended SPIs). The eSPIs includes an additional 1024 SPIs

Well, this is awkward and confusing now. You can't allocate 5088 SPIs,
because no GIC does not support this. Number of SPIs is
960 (regular SPIs) + 1024 (eSPIs) = 1984.

What you are describing is "max SPI number", but the parameter is called
"nr_spis". If we want to leave things consistent, we either need to
deprecate nr_spis in favor of max_spi_nr, or severely rework nr_spi
logic, so it can have values from 0 to 1984...

Personally, I'd prefer max_spi_nr approach, because it will be less
confusing for a user. I am curios what ARM maintainers think about this.


> +from the eSPI range (4096 to 5119) if the hardware supports extended SPIs
> +(GICv3.1+) and CONFIG_GICV3_ESPI is enabled. If the `nr_spis` parameter is 
> not
> +specified, the value calculated by the toolstack will be used for the domain.
> +Otherwise, the value specified by the `nr_spis` parameter will be used. The
> +number of SPIs should match the highest interrupt ID that will be assigned to
> +the domain.
>  
>  =item B<trap_unmapped_accesses=BOOLEAN>

-- 
WBR, Volodymyr