[PATCH v5 29/38] gpu: nova-core: Hopper/Blackwell: larger non-WPR heap

From: John Hubbard

Date: Fri Feb 20 2026 - 21:17:21 EST


Add dedicated FB HALs for Hopper (GH100) and Blackwell (GB100) with
architecture-specific non-WPR heap sizes. Hopper uses 2 MiB, Blackwell
uses 2 MiB + 128 KiB. These are needed for the larger reserved memory
regions that Hopper/Blackwell GPUs require.

Also adds the non_wpr_heap_size() method to the FbHal trait, and
the total_reserved_size field to FbLayout.

Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
---
drivers/gpu/nova-core/fb.rs | 16 ++++++++---
drivers/gpu/nova-core/fb/hal.rs | 16 ++++++++---
drivers/gpu/nova-core/fb/hal/ga102.rs | 2 +-
drivers/gpu/nova-core/fb/hal/gb100.rs | 38 +++++++++++++++++++++++++++
drivers/gpu/nova-core/fb/hal/gh100.rs | 38 +++++++++++++++++++++++++++
5 files changed, 102 insertions(+), 8 deletions(-)
create mode 100644 drivers/gpu/nova-core/fb/hal/gb100.rs
create mode 100644 drivers/gpu/nova-core/fb/hal/gh100.rs

diff --git a/drivers/gpu/nova-core/fb.rs b/drivers/gpu/nova-core/fb.rs
index 0e3519e5ccc0..8b3ba9c9f464 100644
--- a/drivers/gpu/nova-core/fb.rs
+++ b/drivers/gpu/nova-core/fb.rs
@@ -31,7 +31,7 @@
regs,
};

-mod hal;
+pub(crate) mod hal;

/// Type holding the sysmem flush memory page, a page of memory to be written into the
/// `NV_PFB_NISO_FLUSH_SYSMEM_ADDR*` registers and used to maintain memory coherency.
@@ -99,6 +99,15 @@ pub(crate) fn unregister(&self, bar: &Bar0) {
}
}

+/// Calculate non-WPR heap size based on chipset architecture.
+/// This matches the logic used in FSP for consistency.
+pub(crate) fn calc_non_wpr_heap_size(chipset: Chipset) -> u64 {
+ hal::fb_hal(chipset)
+ .non_wpr_heap_size()
+ .map(u64::from)
+ .unwrap_or(usize_as_u64(SZ_1M))
+}
+
pub(crate) struct FbRange(Range<u64>);

impl FbRange {
@@ -253,9 +262,8 @@ pub(crate) fn new(chipset: Chipset, bar: &Bar0, gsp_fw: &GspFirmware) -> Result<
};

let heap = {
- const HEAP_SIZE: u64 = usize_as_u64(SZ_1M);
-
- FbRange(wpr2.start - HEAP_SIZE..wpr2.start)
+ let heap_size = calc_non_wpr_heap_size(chipset);
+ FbRange(wpr2.start - heap_size..wpr2.start)
};

Ok(Self {
diff --git a/drivers/gpu/nova-core/fb/hal.rs b/drivers/gpu/nova-core/fb/hal.rs
index d33ca0f96417..ebd12247f771 100644
--- a/drivers/gpu/nova-core/fb/hal.rs
+++ b/drivers/gpu/nova-core/fb/hal.rs
@@ -12,6 +12,8 @@

mod ga100;
mod ga102;
+mod gb100;
+mod gh100;
mod tu102;

pub(crate) trait FbHal {
@@ -28,14 +30,22 @@ pub(crate) trait FbHal {

/// Returns the VRAM size, in bytes.
fn vidmem_size(&self, bar: &Bar0) -> u64;
+
+ /// Returns the non-WPR heap size for GPUs that need large reserved memory.
+ ///
+ /// Returns `None` for GPUs that don't need extra reserved memory.
+ fn non_wpr_heap_size(&self) -> Option<u32> {
+ None
+ }
}

/// Returns the HAL corresponding to `chipset`.
-pub(super) fn fb_hal(chipset: Chipset) -> &'static dyn FbHal {
+pub(crate) fn fb_hal(chipset: Chipset) -> &'static dyn FbHal {
match chipset.arch() {
Architecture::Turing => tu102::TU102_HAL,
Architecture::Ampere if chipset == Chipset::GA100 => ga100::GA100_HAL,
- Architecture::Ampere => ga102::GA102_HAL,
- Architecture::Ada | Architecture::Hopper | Architecture::Blackwell => ga102::GA102_HAL,
+ Architecture::Ampere | Architecture::Ada => ga102::GA102_HAL,
+ Architecture::Hopper => gh100::GH100_HAL,
+ Architecture::Blackwell => gb100::GB100_HAL,
}
}
diff --git a/drivers/gpu/nova-core/fb/hal/ga102.rs b/drivers/gpu/nova-core/fb/hal/ga102.rs
index 734605905031..f8d8f01e3c5d 100644
--- a/drivers/gpu/nova-core/fb/hal/ga102.rs
+++ b/drivers/gpu/nova-core/fb/hal/ga102.rs
@@ -8,7 +8,7 @@
regs, //
};

-fn vidmem_size_ga102(bar: &Bar0) -> u64 {
+pub(super) fn vidmem_size_ga102(bar: &Bar0) -> u64 {
regs::NV_USABLE_FB_SIZE_IN_MB::read(bar).usable_fb_size()
}

diff --git a/drivers/gpu/nova-core/fb/hal/gb100.rs b/drivers/gpu/nova-core/fb/hal/gb100.rs
new file mode 100644
index 000000000000..bead99a6ca76
--- /dev/null
+++ b/drivers/gpu/nova-core/fb/hal/gb100.rs
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use kernel::prelude::*;
+
+use crate::{
+ driver::Bar0,
+ fb::hal::FbHal, //
+};
+
+struct Gb100;
+
+impl FbHal for Gb100 {
+ fn read_sysmem_flush_page(&self, bar: &Bar0) -> u64 {
+ super::ga100::read_sysmem_flush_page_ga100(bar)
+ }
+
+ fn write_sysmem_flush_page(&self, bar: &Bar0, addr: u64) -> Result {
+ super::ga100::write_sysmem_flush_page_ga100(bar, addr);
+
+ Ok(())
+ }
+
+ fn supports_display(&self, bar: &Bar0) -> bool {
+ super::ga100::display_enabled_ga100(bar)
+ }
+
+ fn vidmem_size(&self, bar: &Bar0) -> u64 {
+ super::ga102::vidmem_size_ga102(bar)
+ }
+
+ fn non_wpr_heap_size(&self) -> Option<u32> {
+ // 2 MiB + 128 KiB non-WPR heap for Blackwell (see Open RM: kgspCalculateFbLayout_GB100).
+ Some(0x220000)
+ }
+}
+
+const GB100: Gb100 = Gb100;
+pub(super) const GB100_HAL: &dyn FbHal = &GB100;
diff --git a/drivers/gpu/nova-core/fb/hal/gh100.rs b/drivers/gpu/nova-core/fb/hal/gh100.rs
new file mode 100644
index 000000000000..32d7414e6243
--- /dev/null
+++ b/drivers/gpu/nova-core/fb/hal/gh100.rs
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use kernel::prelude::*;
+
+use crate::{
+ driver::Bar0,
+ fb::hal::FbHal, //
+};
+
+struct Gh100;
+
+impl FbHal for Gh100 {
+ fn read_sysmem_flush_page(&self, bar: &Bar0) -> u64 {
+ super::ga100::read_sysmem_flush_page_ga100(bar)
+ }
+
+ fn write_sysmem_flush_page(&self, bar: &Bar0, addr: u64) -> Result {
+ super::ga100::write_sysmem_flush_page_ga100(bar, addr);
+
+ Ok(())
+ }
+
+ fn supports_display(&self, bar: &Bar0) -> bool {
+ super::ga100::display_enabled_ga100(bar)
+ }
+
+ fn vidmem_size(&self, bar: &Bar0) -> u64 {
+ super::ga102::vidmem_size_ga102(bar)
+ }
+
+ fn non_wpr_heap_size(&self) -> Option<u32> {
+ // 2 MiB non-WPR heap for Hopper (see Open RM: kgspCalculateFbLayout_GH100).
+ Some(0x200000)
+ }
+}
+
+const GH100: Gh100 = Gh100;
+pub(super) const GH100_HAL: &dyn FbHal = &GH100;
--
2.53.0