1 files changed, 28 insertions, 3 deletions
diff --git a/drivers/gpu/nova-core/fb/hal/gh100.rs b/drivers/gpu/nova-core/fb/hal/gh100.rs
index 5450c7254dad..d39fe99537ed 100644
--- a/drivers/gpu/nova-core/fb/hal/gh100.rs
+++ b/drivers/gpu/nova-core/fb/hal/gh100.rs
@@ -2,24 +2,49 @@
 // SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 
 use kernel::{
+    io::Io,
+    num::Bounded,
     prelude::*,
     sizes::SizeConstants, //
 };
 
 use crate::{
     driver::Bar0,
-    fb::hal::FbHal, //
+    fb::hal::FbHal,
+    regs, //
 };
 
 struct Gh100;
 
+fn read_sysmem_flush_page_gh100(bar: Bar0<'_>) -> u64 {
+    let lo = u64::from(bar.read(regs::NV_PFB_FBHUB_PCIE_FLUSH_SYSMEM_ADDR_LO).adr());
+    let hi = u64::from(bar.read(regs::NV_PFB_FBHUB_PCIE_FLUSH_SYSMEM_ADDR_HI).adr());
+
+    (hi << 32) | lo
+}
+
+/// Write the sysmem flush page address through the Hopper FBHUB registers.
+fn write_sysmem_flush_page_gh100(bar: Bar0<'_>, addr: Bounded<u64, 52>) {
+    // Write HI first. The hardware will trigger the flush on the LO write.
+    bar.write_reg(
+        regs::NV_PFB_FBHUB_PCIE_FLUSH_SYSMEM_ADDR_HI::zeroed()
+            .with_adr(addr.shr::<32, 20>().cast::<u32>()),
+    );
+    bar.write_reg(
+        // CAST: lower 32 bits. Hardware ignores bits 7:0.
+        regs::NV_PFB_FBHUB_PCIE_FLUSH_SYSMEM_ADDR_LO::zeroed().with_adr(*addr as u32),
+    );
+}
+
 impl FbHal for Gh100 {
     fn read_sysmem_flush_page(&self, bar: Bar0<'_>) -> u64 {
-        super::ga100::read_sysmem_flush_page_ga100(bar)
+        read_sysmem_flush_page_gh100(bar)
     }
 
     fn write_sysmem_flush_page(&self, bar: Bar0<'_>, addr: u64) -> Result {
-        super::ga100::write_sysmem_flush_page_ga100(bar, addr);
+        let addr = Bounded::<u64, 52>::try_new(addr).ok_or(EINVAL)?;
+
+        write_sysmem_flush_page_gh100(bar, addr);
 
         Ok(())
     }