Re: [PATCH v2 13/12] nova-core: sequencer: Refactor run() to handle unknown messages

["Alexandre Courbot" <acourbot@nvidia.com>]

Hi Joel,

On Wed Nov 5, 2025 at 8:26 AM JST, Joel Fernandes wrote:
> Refactor GspSequencer::run() to follow the same pattern as gsp_init_done()
> by wrapping message reception in a loop that ignores unknown messages
> (ERANGE errors).

Can you squash this code into the appropriate patch when you respin the
series?

>
> Suggested-by: Timur Tabi <ttabi@nvidia.com>
> Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
> ---
> Additional patch to cure probe issue on Timur's GA102 (which happens to receive
> too many NOCAT records).
>
>  drivers/gpu/nova-core/gsp/sequencer.rs | 86 +++++++++++++++-----------
>  1 file changed, 49 insertions(+), 37 deletions(-)
>
> diff --git a/drivers/gpu/nova-core/gsp/sequencer.rs b/drivers/gpu/nova-core/gsp/sequencer.rs
> index ecc80f668dc8..b98e5146abd8 100644
> --- a/drivers/gpu/nova-core/gsp/sequencer.rs
> +++ b/drivers/gpu/nova-core/gsp/sequencer.rs
> @@ -35,8 +35,8 @@ impl MessageFromGsp for fw::rpc_run_cpu_sequencer_v17_00 {
>  
>  const CMD_SIZE: usize = size_of::<fw::GSP_SEQUENCER_BUFFER_CMD>();
>  
> -struct GspSequencerInfo<'a> {
> -    info: &'a fw::rpc_run_cpu_sequencer_v17_00,
> +struct GspSequencerInfo {
> +    cmd_index: u32,
>      cmd_data: KVec<u8>,
>  }
>  
> @@ -125,7 +125,7 @@ pub(crate) fn size_bytes(&self) -> usize {
>  }
>  
>  pub(crate) struct GspSequencer<'a> {
> -    seq_info: GspSequencerInfo<'a>,
> +    seq_info: GspSequencerInfo,

I've looked at how `GspSequencere`, `GspSequencerParams` and
`GspSequencerInfo` interact after this patch, and I think we can
simplify the design a bit (based on the v9 of the GSP boot series).

`GspSequencerInfo` is actually the sequence (so we should name it
`GspSequence`?) we want to run. As such, it can be created by
implementing the `MessageFromGsp` trait, and received directly from
`boot.rs` by moving the loop at the beginning of `GspSequencer::run` to
`boot.rs`. This allows to remove the `cmdq` argument from the `run`
method, which looked a bit out of place.

In its place, we can pass the sequence to `run`. It doesn't need to be
stored in the `GspSequencer` struct, as we can just implement `Iterator`
on it and read its commands from `run` directly. Once you remove it from
`GspSequencer`, something interesting happens: `GspSequencer` and
`GspSequencerParams` are now exactly the same! So we can remove the
params, simply build the sequencer using a regular constructor, and call
`run` on it with the sequence.