Re: [PATCH v2 7/7] gpu: nova-core: reserve larger WPR2 heap for vGPU

[Alexandre Courbot]

On Tue Jun 23, 2026 at 4:43 AM JST, Zhi Wang wrote:
> From: Zhi Wang <zhi.wang.ai@xxxxxxxx>
>
> Reserve a larger GSP WPR2 heap when vGPU is enabled, using the VF count
> reported by VgpuManager to select the heap size and to populate the VF
> partition count in the GSP WPR metadata.
>
> Use the baremetal heap sizing path when vGPU is disabled. For vGPU,
> reserve 581 MiB for up to 32 VFs and 1370 MiB for larger VF counts.
>
> Signed-off-by: Zhi Wang <zhiw@xxxxxxxxxx>
> ---
>  drivers/gpu/nova-core/fb.rs       | 25 ++++++++++++++++++++-----
>  drivers/gpu/nova-core/gsp.rs      |  1 +
>  drivers/gpu/nova-core/gsp/boot.rs |  2 +-
>  drivers/gpu/nova-core/gsp/fw.rs   | 10 ++++++++++
>  4 files changed, 32 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/nova-core/fb.rs b/drivers/gpu/nova-core/fb.rs
> index 725e428154cf..b5b1f6c13edc 100644
> --- a/drivers/gpu/nova-core/fb.rs
> +++ b/drivers/gpu/nova-core/fb.rs
> @@ -24,7 +24,8 @@
>      gpu::Chipset,
>      gsp,
>      num::FromSafeCast,
> -    regs, //
> +    regs,
> +    vgpu::VgpuManager, //
>  };
>  
>  mod hal;
> @@ -171,7 +172,12 @@ pub(crate) struct FbLayout {
>  
>  impl FbLayout {
>      /// Computes the FB layout for `chipset` required to run the `gsp_fw` GSP firmware.
> -    pub(crate) fn new(chipset: Chipset, bar: Bar0<'_>, gsp_fw: &GspFirmware) -> Result<Self> {
> +    pub(crate) fn new(
> +        chipset: Chipset,
> +        bar: Bar0<'_>,
> +        gsp_fw: &GspFirmware,
> +        vgpu: &VgpuManager,
> +    ) -> Result<Self> {
>          let hal = hal::fb_hal(chipset);
>  
>          let fb = {
> @@ -234,10 +240,19 @@ pub(crate) fn new(chipset: Chipset, bar: Bar0<'_>, gsp_fw: &GspFirmware) -> Resu
>              FbRange(elf_addr..elf_addr + elf_size)
>          };
>  
> +        let vf_partition_count = if vgpu.enabled() {
> +            vgpu.total_vfs().try_into().map_err(|_| EINVAL)?
> +        } else {
> +            0
> +        };
> +
>          let wpr2_heap = {
>              const WPR2_HEAP_DOWN_ALIGN: Alignment = Alignment::new::<SZ_1M>();
> -            let wpr2_heap_size =
> -                gsp::LibosParams::from_chipset(chipset).wpr_heap_size(chipset, fb.end)?;
> +            let wpr2_heap_size = if vgpu.enabled() {
> +                gsp::vgpu_fw_heap_size(u32::from(vgpu.total_vfs()))
> +            } else {
> +                gsp::LibosParams::from_chipset(chipset).wpr_heap_size(chipset, fb.end)?
> +            };
>              let wpr2_heap_addr = (elf.start - wpr2_heap_size).align_down(WPR2_HEAP_DOWN_ALIGN);
>  
>              FbRange(wpr2_heap_addr..(elf.start).align_down(WPR2_HEAP_DOWN_ALIGN))
> @@ -265,7 +280,7 @@ pub(crate) fn new(chipset: Chipset, bar: Bar0<'_>, gsp_fw: &GspFirmware) -> Resu
>              wpr2_heap,
>              wpr2,
>              heap,
> -            vf_partition_count: 0,
> +            vf_partition_count,
>              pmu_reserved_size: hal.pmu_reserved_size(),
>          })
>      }
> diff --git a/drivers/gpu/nova-core/gsp.rs b/drivers/gpu/nova-core/gsp.rs
> index 6821008d48d9..a159f36bf704 100644
> --- a/drivers/gpu/nova-core/gsp.rs
> +++ b/drivers/gpu/nova-core/gsp.rs
> @@ -26,6 +26,7 @@
>  mod sequencer;
>  
>  pub(crate) use fw::{
> +    vgpu_fw_heap_size,
>      GspFmcBootParams,
>      GspFwWprMeta,
>      LibosParams, //
> diff --git a/drivers/gpu/nova-core/gsp/boot.rs b/drivers/gpu/nova-core/gsp/boot.rs
> index c607081e8242..dea028f4b434 100644
> --- a/drivers/gpu/nova-core/gsp/boot.rs
> +++ b/drivers/gpu/nova-core/gsp/boot.rs
> @@ -56,7 +56,7 @@ pub(crate) fn boot(
>  
>          let gsp_fw = KBox::pin_init(GspFirmware::new(dev, chipset, FIRMWARE_VERSION), GFP_KERNEL)?;
>  
> -        let fb_layout = FbLayout::new(chipset, bar, &gsp_fw)?;
> +        let fb_layout = FbLayout::new(chipset, bar, &gsp_fw, ctx.vgpu)?;
>          dev_dbg!(dev, "{:#x?}\n", fb_layout);
>  
>          let wpr_meta = Coherent::init(dev, GFP_KERNEL, GspFwWprMeta::new(&gsp_fw, &fb_layout))?;
> diff --git a/drivers/gpu/nova-core/gsp/fw.rs b/drivers/gpu/nova-core/gsp/fw.rs
> index 4db0cfa4dc4d..2fb72f8dc3c9 100644
> --- a/drivers/gpu/nova-core/gsp/fw.rs
> +++ b/drivers/gpu/nova-core/gsp/fw.rs
> @@ -101,6 +101,16 @@ pub(in crate::gsp) fn advance_cpu_write_ptr(qs: &Coherent<GspMem>, count: u32) {
>  pub(crate) const GSP_MSG_QUEUE_ELEMENT_SIZE_MAX: usize =
>      num::u32_as_usize(bindings::GSP_MSG_QUEUE_ELEMENT_SIZE_MAX);
>  
> +const GSP_FW_HEAP_SIZE_VGPU_DEFAULT: u64 = 581 * u64::SZ_1M;
> +const GSP_FW_HEAP_SIZE_VGPU_48VMS: u64 = 1370 * u64::SZ_1M;
> +
> +pub(crate) fn vgpu_fw_heap_size(total_vfs: u32) -> u64 {
> +    match total_vfs {
> +        2..=32 => GSP_FW_HEAP_SIZE_VGPU_DEFAULT,
> +        _ => GSP_FW_HEAP_SIZE_VGPU_48VMS,
> +    }

Note that this is also going to return an (presumably invalid) value if
`total_vfs` is `0` or `1`. Should it return `0` for these?