[PATCH v10 03/21] gpu: nova-core: gsp: Expose total physical VRAM end from FB region info

Joel Fernandes
2026-03-31T21:21:18Z

Add `total_fb_end()` to `GspStaticConfigInfo` that computes the
exclusive end address of the highest valid FB region covering both
usable and GSP-reserved areas.

This allows callers to know the full physical VRAM extent, not just
the allocatable portion.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
---
drivers/gpu/nova-core/gsp/commands.rs | 6 ++++++
drivers/gpu/nova-core/gsp/fw/commands.rs | 7 +++++++
2 files changed, 13 insertions(+)

diff --git a/drivers/gpu/nova-core/gsp/commands.rs b/drivers/gpu/nova-core/gsp/commands.rs
index 41742c1633c8..5e0649024637 100644
--- a/drivers/gpu/nova-core/gsp/commands.rs
+++ b/drivers/gpu/nova-core/gsp/commands.rs
@@ -196,6 +196,9 @@ pub(crate) struct GetGspStaticInfoReply {
/// Usable FB (VRAM) region for driver memory allocation.
#[expect(dead_code)]
pub(crate) usable_fb_region: Range<u64>,
+ /// End of VRAM.
+ #[expect(dead_code)]
+ pub(crate) total_fb_end: u64,
}

impl MessageFromGsp for GetGspStaticInfoReply {
@@ -209,9 +212,12 @@ fn read(
) -> Result<Self, Self::InitError> {
let (base, size) = msg.first_usable_fb_region().ok_or(ENODEV)?;

+ let total_fb_end = msg.total_fb_end().ok_or(ENODEV)?;
+
Ok(GetGspStaticInfoReply {
gpu_name: msg.gpu_name_str(),
usable_fb_region: base..base.saturating_add(size),
+ total_fb_end,
})
}
}
diff --git a/drivers/gpu/nova-core/gsp/fw/commands.rs b/drivers/gpu/nova-core/gsp/fw/commands.rs
index 9fffa74d03f9..46932d5c8c1d 100644
--- a/drivers/gpu/nova-core/gsp/fw/commands.rs
+++ b/drivers/gpu/nova-core/gsp/fw/commands.rs
@@ -163,6 +163,13 @@ pub(crate) fn first_usable_fb_region(&self) -> Option<(u64, u64)> {
}
})
}
+
+ /// Compute the end of physical VRAM from all FB regions.
+ pub(crate) fn total_fb_end(&self) -> Option<u64> {
+ self.fb_regions()
+ .map(|reg| reg.limit.saturating_add(1))
+ .max()
+ }
}

// SAFETY: Padding is explicit and will not contain uninitialized data.
--
2.34.1