Re: [PATCH v8 12/31] gpu: nova-core: Hopper/Blackwell: add FMC firmware image, in support of FSP

[Gary Guo]

On Wed Mar 25, 2026 at 3:52 AM GMT, John Hubbard wrote:
> FSP is the Falcon that runs FMC firmware on Hopper and Blackwell.
> Load the FMC ELF in two forms: the image section that FSP boots from,
> and a CPU-side copy of the full ELF for later signature extraction
> during Chain of Trust verification.
>
> Co-developed-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
> Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
> Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
> ---
>  drivers/gpu/nova-core/firmware.rs     |  1 +
>  drivers/gpu/nova-core/firmware/fsp.rs | 47 +++++++++++++++++++++++++++
>  2 files changed, 48 insertions(+)
>  create mode 100644 drivers/gpu/nova-core/firmware/fsp.rs
>
> diff --git a/drivers/gpu/nova-core/firmware.rs b/drivers/gpu/nova-core/firmware.rs
> index bc217bfc225f..bc26807116e4 100644
> --- a/drivers/gpu/nova-core/firmware.rs
> +++ b/drivers/gpu/nova-core/firmware.rs
> @@ -27,6 +27,7 @@
>  };
>  
>  pub(crate) mod booter;
> +pub(crate) mod fsp;
>  pub(crate) mod fwsec;
>  pub(crate) mod gsp;
>  pub(crate) mod riscv;
> diff --git a/drivers/gpu/nova-core/firmware/fsp.rs b/drivers/gpu/nova-core/firmware/fsp.rs
> new file mode 100644
> index 000000000000..5aedee8e6d41
> --- /dev/null
> +++ b/drivers/gpu/nova-core/firmware/fsp.rs
> @@ -0,0 +1,47 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +//! FSP is a hardware unit that runs FMC firmware.
> +
> +use kernel::{
> +    alloc::KVec,
> +    device,
> +    prelude::*, //
> +};
> +
> +use crate::{
> +    dma::DmaObject,
> +    firmware::elf,
> +    gpu::Chipset, //
> +};
> +
> +#[expect(unused)]
> +pub(crate) struct FspFirmware {
> +    /// FMC firmware image data (only the "image" ELF section).
> +    fmc_image: DmaObject,
> +    /// Full FMC ELF data (for signature extraction).
> +    pub(crate) fmc_full: KVec<u8>,
> +}
> +
> +impl FspFirmware {
> +    #[expect(unused)]
> +    pub(crate) fn new(
> +        dev: &device::Device<device::Bound>,
> +        chipset: Chipset,
> +        ver: &str,
> +    ) -> Result<Self> {
> +        let fw = super::request_firmware(dev, chipset, "fmc", ver)?;
> +        let mut fmc_full = KVec::with_capacity(fw.data().len(), GFP_KERNEL)?;
> +        fmc_full.extend_from_slice(fw.data(), GFP_KERNEL)?;

What's this copy for? It looks like you never need to modify it, so keeping hold
on `Firmware` should be fine?

Best,
Gary

> +
> +        // FSP expects only the "image" section, not the entire ELF file.
> +        let fmc_image_data = elf::elf_section(fw.data(), "image").ok_or_else(|| {
> +            dev_err!(dev, "FMC ELF file missing 'image' section\n");
> +            EINVAL
> +        })?;
> +
> +        Ok(Self {
> +            fmc_image: DmaObject::from_data(dev, fmc_image_data)?,
> +            fmc_full,
> +        })
> +    }
> +}