gpu: nova-core: falcon: add distinct base address for PFALCON2

Falcon engines have two distinct register bases: `PFALCON` and
`PFALCON2`. So far we assumed that `PFALCON2` was located at `PFALCON +
0x1000` because that is the case of most engines, but there are
exceptions (NVDEC uses `0x1c00`).

Fix this shortcoming by leveraging the redesigned relative registers
definitions to assign a distinct `PFalcon2Base` base address to each
falcon engine.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250718-nova-regs-v2-16-7b6a762aa1cd@nvidia.com
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>

drivers/gpu/nova-core/falcon.rs

@@ -278,11 +278,16 @@ impl From<bool> for FalconFbifMemType {
 /// Type used to represent the `PFALCON` registers address base for a given falcon engine.
 pub(crate) struct PFalconBase(());
 
+/// Type used to represent the `PFALCON2` registers address base for a given falcon engine.
+pub(crate) struct PFalcon2Base(());
+
 /// Trait defining the parameters of a given Falcon engine.
 ///
 /// Each engine provides one base for `PFALCON` and `PFALCON2` registers. The `ID` constant is used
 /// to identify a given Falcon instance with register I/O methods.
-pub(crate) trait FalconEngine: Sync + RegisterBase<PFalconBase> + Sized {
+pub(crate) trait FalconEngine:
+    Sync + RegisterBase<PFalconBase> + RegisterBase<PFalcon2Base> + Sized
+{
     /// Singleton of the engine, used to identify it with register I/O methods.
     const ID: Self;
 }

drivers/gpu/nova-core/falcon/gsp.rs

@@ -2,7 +2,7 @@
 
 use crate::{
     driver::Bar0,
-    falcon::{Falcon, FalconEngine, PFalconBase},
+    falcon::{Falcon, FalconEngine, PFalcon2Base, PFalconBase},
     regs::{self, macros::RegisterBase},
 };
 
@@ -13,6 +13,10 @@ impl RegisterBase<PFalconBase> for Gsp {
     const BASE: usize = 0x00110000;
 }
 
+impl RegisterBase<PFalcon2Base> for Gsp {
+    const BASE: usize = 0x00111000;
+}
+
 impl FalconEngine for Gsp {
     const ID: Self = Gsp(());
 }

drivers/gpu/nova-core/falcon/sec2.rs

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 
-use crate::falcon::{FalconEngine, PFalconBase};
+use crate::falcon::{FalconEngine, PFalcon2Base, PFalconBase};
 use crate::regs::macros::RegisterBase;
 
 /// Type specifying the `Sec2` falcon engine. Cannot be instantiated.
@@ -10,6 +10,10 @@ impl RegisterBase<PFalconBase> for Sec2 {
     const BASE: usize = 0x00840000;
 }
 
+impl RegisterBase<PFalcon2Base> for Sec2 {
+    const BASE: usize = 0x00841000;
+}
+
 impl FalconEngine for Sec2 {
     const ID: Self = Sec2(());
 }

drivers/gpu/nova-core/regs.rs

@@ -9,7 +9,7 @@ pub(crate) mod macros;
 
 use crate::falcon::{
     DmaTrfCmdSize, FalconCoreRev, FalconCoreRevSubversion, FalconFbifMemType, FalconFbifTarget,
-    FalconModSelAlgo, FalconSecurityModel, PFalconBase, PeregrineCoreSelect,
+    FalconModSelAlgo, FalconSecurityModel, PFalcon2Base, PFalconBase, PeregrineCoreSelect,
 };
 use crate::gpu::{Architecture, Chipset};
 use kernel::prelude::*;
@@ -296,20 +296,22 @@ register!(NV_PFALCON_FBIF_CTL @ PFalconBase[0x00000624] {
     7:7     allow_phys_no_ctx as bool;
 });
 
-register!(NV_PFALCON2_FALCON_MOD_SEL @ PFalconBase[0x00001180] {
+/* PFALCON2 */
+
+register!(NV_PFALCON2_FALCON_MOD_SEL @ PFalcon2Base[0x00000180] {
     7:0     algo as u8 ?=> FalconModSelAlgo;
 });
 
-register!(NV_PFALCON2_FALCON_BROM_CURR_UCODE_ID @ PFalconBase[0x00001198] {
+register!(NV_PFALCON2_FALCON_BROM_CURR_UCODE_ID @ PFalcon2Base[0x00000198] {
     7:0    ucode_id as u8;
 });
 
-register!(NV_PFALCON2_FALCON_BROM_ENGIDMASK @ PFalconBase[0x0000119c] {
+register!(NV_PFALCON2_FALCON_BROM_ENGIDMASK @ PFalcon2Base[0x0000019c] {
     31:0    value as u32;
 });
 
 // TODO[REGA]: this is an array of registers.
-register!(NV_PFALCON2_FALCON_BROM_PARAADDR @ PFalconBase[0x00001210] {
+register!(NV_PFALCON2_FALCON_BROM_PARAADDR @ PFalcon2Base[0x00000210] {
     31:0    value as u32;
 });