Re: [PATCH v4 20/20] gpu: nova-core: load and run FWSEC-FRTS

[Lyude Paul <lyude@redhat.com>]

On Wed, 2025-05-21 at 15:45 +0900, Alexandre Courbot wrote:
> With all the required pieces in place, load FWSEC-FRTS onto the GSP
> falcon, run it, and check that it successfully carved out the WPR2
> region out of framebuffer memory.
> 
> Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
> ---
>  drivers/gpu/nova-core/falcon.rs |  3 ---
>  drivers/gpu/nova-core/gpu.rs    | 57 ++++++++++++++++++++++++++++++++++++++++-
>  drivers/gpu/nova-core/regs.rs   | 15 +++++++++++
>  3 files changed, 71 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/nova-core/falcon.rs b/drivers/gpu/nova-core/falcon.rs
> index f224ca881b72954d17fee87278ecc7a0ffac5322..91f0451a04e7b4d0631fbcf9b1e76e59d5dfb7e8 100644
> --- a/drivers/gpu/nova-core/falcon.rs
> +++ b/drivers/gpu/nova-core/falcon.rs
> @@ -2,9 +2,6 @@
>  
>  //! Falcon microprocessor base support
>  
> -// To be removed when all code is used.
> -#![expect(dead_code)]
> -
>  use core::ops::Deref;
>  use core::time::Duration;
>  use hal::FalconHal;
> diff --git a/drivers/gpu/nova-core/gpu.rs b/drivers/gpu/nova-core/gpu.rs
> index 5a4c23a7a6c22abc1f6e72a307fa3336d731a396..280929203189fba6ad8e37709927597bb9c7d545 100644
> --- a/drivers/gpu/nova-core/gpu.rs
> +++ b/drivers/gpu/nova-core/gpu.rs
> @@ -246,7 +246,7 @@ pub(crate) fn new(
>  
>          let bios = Vbios::new(pdev, bar)?;
>  
> -        let _fwsec_frts = FwsecFirmware::new(
> +        let fwsec_frts = FwsecFirmware::new(
>              &gsp_falcon,
>              pdev.as_ref(),
>              bar,
> @@ -257,6 +257,61 @@ pub(crate) fn new(
>              },
>          )?;
>  
> +        // Check that the WPR2 region does not already exists - if it does, the GPU needs to be
> +        // reset.
> +        if regs::NV_PFB_PRI_MMU_WPR2_ADDR_HI::read(bar).hi_val() != 0 {
> +            dev_err!(
> +                pdev.as_ref(),
> +                "WPR2 region already exists - GPU needs to be reset to proceed\n"
> +            );
> +            return Err(EBUSY);
> +        }
> +
> +        // Reset falcon, load FWSEC-FRTS, and run it.
> +        gsp_falcon.reset(bar)?;
> +        gsp_falcon.dma_load(bar, &fwsec_frts)?;
> +        let (mbox0, _) = gsp_falcon.boot(bar, Some(0), None)?;
> +        if mbox0 != 0 {
> +            dev_err!(pdev.as_ref(), "FWSEC firmware returned error {}\n", mbox0);
> +            return Err(EINVAL);
> +        }
> +
> +        // SCRATCH_E contains FWSEC-FRTS' error code, if any.
> +        let frts_status = regs::NV_PBUS_SW_SCRATCH_0E::read(bar).frts_err_code();
> +        if frts_status != 0 {
> +            dev_err!(
> +                pdev.as_ref(),
> +                "FWSEC-FRTS returned with error code {:#x}",
> +                frts_status
> +            );
> +            return Err(EINVAL);
> +        }
> +
> +        // Check the WPR2 has been created as we requested.
> +        let (wpr2_lo, wpr2_hi) = (
> +            (regs::NV_PFB_PRI_MMU_WPR2_ADDR_LO::read(bar).lo_val() as u64) << 12,
> +            (regs::NV_PFB_PRI_MMU_WPR2_ADDR_HI::read(bar).hi_val() as u64) << 12,
> +        );
> +        if wpr2_hi == 0 {
> +            dev_err!(
> +                pdev.as_ref(),
> +                "WPR2 region not created after running FWSEC-FRTS\n"
> +            );
> +
> +            return Err(ENOTTY);

ENOTTY? Is this correct?

> +        } else if wpr2_lo != fb_layout.frts.start {
> +            dev_err!(
> +                pdev.as_ref(),
> +                "WPR2 region created at unexpected address {:#x} ; expected {:#x}\n",

Extra space (but if that's intentional, feel free to leave it)

Besides those two nits: Reviewed-by: Lyude Paul <lyude@redhat.com>

> +                wpr2_lo,
> +                fb_layout.frts.start,
> +            );
> +            return Err(EINVAL);
> +        }
> +
> +        dev_dbg!(pdev.as_ref(), "WPR2: {:#x}-{:#x}\n", wpr2_lo, wpr2_hi);
> +        dev_dbg!(pdev.as_ref(), "GPU instance built\n");
> +
>          Ok(pin_init!(Self {
>              spec,
>              bar: devres_bar,
> diff --git a/drivers/gpu/nova-core/regs.rs b/drivers/gpu/nova-core/regs.rs
> index 54d4d37d6bf2c31947b965258d2733009c293a18..2a2d5610e552780957bcf00e0da1ec4cd3ac85d2 100644
> --- a/drivers/gpu/nova-core/regs.rs
> +++ b/drivers/gpu/nova-core/regs.rs
> @@ -42,6 +42,13 @@ pub(crate) fn chipset(self) -> Result<Chipset> {
>      }
>  }
>  
> +/* PBUS */
> +
> +// TODO: this is an array of registers.
> +register!(NV_PBUS_SW_SCRATCH_0E@0x00001438  {
> +    31:16   frts_err_code as u16;
> +});
> +
>  /* PFB */
>  
>  register!(NV_PFB_NISO_FLUSH_SYSMEM_ADDR @ 0x00100c10 {
> @@ -73,6 +80,14 @@ pub(crate) fn usable_fb_size(self) -> u64 {
>      }
>  }
>  
> +register!(NV_PFB_PRI_MMU_WPR2_ADDR_LO@0x001fa824  {
> +    31:4    lo_val as u32;
> +});
> +
> +register!(NV_PFB_PRI_MMU_WPR2_ADDR_HI@0x001fa828  {
> +    31:4    hi_val as u32;
> +});
> +
>  /* PGC6 */
>  
>  register!(NV_PGC6_AON_SECURE_SCRATCH_GROUP_05_PRIV_LEVEL_MASK @ 0x00118128 {
> 

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat

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