Re: [PATCH v10 02/21] gpu: nova-core: gsp: Extract usable FB region from GSP

Alexandre Courbot
2026-04-09T08:45:45Z

On Wed Apr 1, 2026 at 6:20 AM JST, Joel Fernandes wrote:
> Add first_usable_fb_region() to GspStaticConfigInfo to extract the first
> usable FB region from GSP's fbRegionInfoParams. Usable regions are those
> that are not reserved or protected.
>
> The extracted region is stored in GetGspStaticInfoReply and exposed as
> usable_fb_region field for use by the memory subsystem.
>
> Cc: Nikola Djukic <ndjukic@nvidia.com>
> Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
> ---
> drivers/gpu/nova-core/gsp/commands.rs | 11 ++++--
> drivers/gpu/nova-core/gsp/fw/commands.rs | 44 +++++++++++++++++++++++-
> 2 files changed, 52 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/nova-core/gsp/commands.rs b/drivers/gpu/nova-core/gsp/commands.rs
> index c89c7b57a751..41742c1633c8 100644
> --- a/drivers/gpu/nova-core/gsp/commands.rs
> +++ b/drivers/gpu/nova-core/gsp/commands.rs
> @@ -4,6 +4,7 @@
> array,
> convert::Infallible,
> ffi::FromBytesUntilNulError,
> + ops::Range,
> str::Utf8Error, //
> };
>
> @@ -189,22 +190,28 @@ fn init(&self) -> impl Init<Self::Command, Self::InitError> {
> }
> }
>
> -/// The reply from the GSP to the [`GetGspInfo`] command.
> +/// The reply from the GSP to the [`GetGspStaticInfo`] command.
> pub(crate) struct GetGspStaticInfoReply {
> gpu_name: [u8; 64],
> + /// Usable FB (VRAM) region for driver memory allocation.
> + #[expect(dead_code)]
> + pub(crate) usable_fb_region: Range<u64>,

Let's print the region when creating the GPU (using `dev_info` or
`dev_dbg`) - this can be useful to the user, and lets us remove this
`dead_code`.