Commit Graph

14 Commits

Author SHA1 Message Date
Tim Kovalenko
c7940c8bf2 gpu: nova-core: fix stack overflow in GSP memory allocation
The `Cmdq::new` function was allocating a `PteArray` struct on the stack
and was causing a stack overflow with 8216 bytes.

Modify the `PteArray` to calculate and write the Page Table Entries
directly into the coherent DMA buffer one-by-one. This reduces the stack
usage quite a lot.

Reported-by: Gary Guo <gary@garyguo.net>
Closes: https://rust-for-linux.zulipchat.com/#narrow/channel/509436-Nova/topic/.60Cmdq.3A.3Anew.60.20uses.20excessive.20stack.20size/near/570375549
Link: https://lore.kernel.org/rust-for-linux/CANiq72mAQxbRJZDnik3Qmd4phvFwPA01O2jwaaXRh_T+2=L-qA@mail.gmail.com/
Fixes: f38b4f105c ("gpu: nova-core: Create initial Gsp")
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Tim Kovalenko <tim.kovalenko@proton.me>
Link: https://patch.msgid.link/20260309-drm-rust-next-v4-4-4ef485b19a4c@proton.me
[ * Use PteArray::entry() in LogBuffer::new(),
  * Add TODO comment to use IoView projections once available,
  * Add PTE_ARRAY_SIZE constant to avoid duplication.

    - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-03-10 18:29:14 +01:00
Gary Guo
4da879a0d3 rust: dma: use pointer projection infra for dma_{read,write} macro
Current `dma_read!`, `dma_write!` macros also use a custom
`addr_of!()`-based implementation for projecting pointers, which has
soundness issue as it relies on absence of `Deref` implementation on types.
It also has a soundness issue where it does not protect against unaligned
fields (when `#[repr(packed)]` is used) so it can generate misaligned
accesses.

This commit migrates them to use the general pointer projection
infrastructure, which handles these cases correctly.

As part of migration, the macro is updated to have an improved surface
syntax. The current macro have

    dma_read!(a.b.c[d].e.f)

to mean `a.b.c` is a DMA coherent allocation and it should project into it
with `[d].e.f` and do a read, which is confusing as it makes the indexing
operator integral to the macro (so it will break if you have an array of
`CoherentAllocation`, for example).

This also is problematic as we would like to generalize
`CoherentAllocation` from just slices to arbitrary types.

Make the macro expects `dma_read!(path.to.dma, .path.inside.dma)` as the
canonical syntax. The index operator is no longer special and is just one
type of projection (in additional to field projection). Similarly, make
`dma_write!(path.to.dma, .path.inside.dma, value)` become the canonical
syntax for writing.

Another issue of the current macro is that it is always fallible. This
makes sense with existing design of `CoherentAllocation`, but once we
support fixed size arrays with `CoherentAllocation`, it is desirable to
have the ability to perform infallible indexing as well, e.g. doing a `[0]`
index of `[Foo; 2]` is okay and can be checked at build-time, so forcing
falliblity is non-ideal. To capture this, the macro is changed to use
`[idx]` as infallible projection and `[idx]?` as fallible index projection
(those syntax are part of the general projection infra). A benefit of this
is that while individual indexing operation may fail, the overall
read/write operation is not fallible.

Fixes: ad2907b4e3 ("rust: add dma coherent allocator abstraction")
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260302164239.284084-4-gary@kernel.org
[ Capitalize safety comments; slightly improve wording in doc-comments.
  - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-03-07 23:06:20 +01:00
Alexandre Courbot
58d26d4281 gpu: nova-core: align LibosMemoryRegionInitArgument size to page size
On Turing and GA100 (i.e. the versions that use Libos v2), GSP-RM insists
that the 'size' parameter of the LibosMemoryRegionInitArgument struct be
aligned to 4KB.  The logging buffers are already aligned to that size, so
only the GSP_ARGUMENTS_CACHED struct needs to be adjusted.  Make that
adjustment by adding padding to the end of the struct.

Signed-off-by: Timur Tabi <ttabi@nvidia.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/20260122222848.2555890-12-ttabi@nvidia.com
[acourbot@nvidia.com: GspArgumentsAligned -> GspArgumentsPadded]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
2026-01-24 10:48:59 +09:00
Danilo Krummrich
7acc70476f gpu: nova-core: gsp: move appropriate code into pin initializer
Relocate the code that technically fits in the pin initializer into the
initializer itself.

While, thanks to pin_init_scope(), it is also possible to keep it as is,
moving appropriate code into the initializer has the advantage that it
structures the dependencies of fields naturally.

For instance, intermediate data that is only needed for a single field
goes into the initializer block of this field, making it obvious that it
is not needed by anything else.

On the other hand, intermediate data that is needed for multiple fields
to initialize remains above the initializer, naturally indicating that
it is needed my multiple fields.

Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Link: https://patch.msgid.link/20251218155239.25243-5-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-12-29 17:54:32 +01:00
Danilo Krummrich
032a6772d6 gpu: nova-core: gsp: get rid of redundant Result in Gsp::new()
In Gsp::new(), utilize pin_init_scope() to get rid of the Result in the
returned

	Result<impl PinInit<T, Error>>

which is unnecessarily redundant.

Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Link: https://patch.msgid.link/20251218155239.25243-4-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-12-29 17:54:31 +01:00
Joel Fernandes
6ddfc892a5 gpu: nova-core: Implement the GSP sequencer
Implement the GSP sequencer which culminates in INIT_DONE message being
received from the GSP indicating that the GSP has successfully booted.

This is just initial sequencer support, the actual commands will be
added in the next patches.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
[acourbot@nvidia.com: move GspSequencerInfo definition before its impl
blocks and rename it to GspSequence, adapt imports in sequencer.rs to
new formatting rules, remove `timeout` argument to harmonize with other
commands.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-8-joelagnelf@nvidia.com>
2025-11-15 21:05:50 +09:00
Alistair Popple
edcb134264 gpu: nova-core: gsp: Add SetSystemInfo command
Add support for sending the SetSystemInfo command, which provides
required hardware information to the GSP and is critical to its
initialization.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-11-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:57 +09:00
Alistair Popple
4fd4acd973 gpu: nova-core: gsp: Create rmargs
Initialise the GSP resource manager arguments (rmargs) which provides
initialisation parameters to the GSP firmware during boot. The rmargs
structure contains arguments to configure the GSP message/command queue
location.

These are mapped for coherent DMA and added to the libos data structure
for access when booting GSP.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Co-developed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-10-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:57 +09:00
Alistair Popple
75f6b1de81 gpu: nova-core: gsp: Add GSP command queue bindings and handling
This commit introduces core infrastructure for handling GSP command and
message queues in the nova-core driver. The command queue system enables
bidirectional communication between the host driver and GSP firmware
through a remote message passing interface.

The interface is based on passing serialised data structures over a ring
buffer with separate transmit and receive queues. Commands are sent by
writing to the CPU transmit queue and waiting for completion via the
receive queue.

To ensure safety mutable or immutable (depending on whether it is a send
or receive operation) references are taken on the command queue when
allocating the message to write/read to. This ensures message memory
remains valid and the command queue can't be mutated whilst an operation
is in progress.

Currently this is only used by the probe() routine and therefore can
only used by a single thread of execution. Locking to enable safe access
from multiple threads will be introduced in a future series when that
becomes necessary.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Co-developed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-9-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:57 +09:00
Alistair Popple
f38b4f105c gpu: nova-core: Create initial Gsp
The GSP requires several areas of memory to operate. Each of these have
their own simple embedded page tables. Set these up and map them for DMA
to/from GSP using CoherentAllocation's. Return the DMA handle describing
where each of these regions are for future use when booting GSP.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Co-developed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-4-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:56 +09:00
Alexandre Courbot
7c01dc25f5 gpu: nova-core: compute layout of more framebuffer regions required for GSP
Compute more of the required FB layout information to boot the GSP
firmware.

This information is dependent on the firmware itself, so first we need
to import and abstract the required firmware bindings in the `nvfw`
module.

Then, a new FB HAL method is introduced in `fb::hal` that uses these
bindings and hardware information to compute the correct layout
information.

This information is then used in `fb` and the result made visible in
`FbLayout`.

These 3 things are grouped into the same patch to avoid lots of unused
warnings that would be tedious to work around. As they happen in
different files, they should not be too difficult to track separately.

Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-1-8ae4058e3c0e@nvidia.com>
2025-11-14 11:05:58 +09:00
Alistair Popple
299eb32863 gpu: nova-core: Add base files for r570.144 firmware bindings
Interacting with the GSP currently requires using definitions from C
header files. Rust definitions for the types needed for Nova core will
be generated using the Rust bindgen tool. This patch adds the base
module to allow inclusion of the generated bindings. The generated
bindings themselves are added by subsequent patches when they are first
used.

Currently we only intend to support a single firmware version, 570.144,
with these bindings. Longer term we intend to move to a more stable GSP
interface that isn't tied to specific firmware versions.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
[acourbot@nvidia.com: adapt the bindings module comment a bit]
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250913-nova_firmware-v6-10-9007079548b0@nvidia.com
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
2025-09-13 23:17:48 +09:00
Alexandre Courbot
a841614e60 gpu: nova-core: firmware: process and prepare the GSP firmware
The GSP firmware is a binary blob that is verified, loaded, and run by
the GSP bootloader. Its presentation is a bit peculiar as the GSP
bootloader expects to be given a DMA address to a 3-levels page table
mapping the GSP firmware at address 0 of its own address space.

Prepare such a structure containing the DMA-mapped firmware as well as
the DMA-mapped page tables, and a way to obtain the DMA handle of the
level 0 page table.

Then, move the GSP firmware instance from the `Firmware` struct to the
`start_gsp` method since it doesn't need to be kept after the GSP is
booted.

As we are performing the required ELF section parsing and radix3 page
table building, remove these items from the TODO file.

Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250913-nova_firmware-v6-7-9007079548b0@nvidia.com
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
2025-09-13 23:17:38 +09:00
Alexandre Courbot
e7c96980ea gpu: nova-core: move GSP boot code to its own module
Right now the GSP boot code is very incomplete and limited to running
FRTS, so having it in `Gpu::new` is not a big constraint.

However, this will change as we add more steps of the GSP boot process,
and not all GPU families follow the same procedure, so having these
steps in a dedicated method is the logical construct.

There is also the fact the GSP will require its own runtime data, and
while it won't immediately need to be pinned, we want to be ready for
the time where it will - most likely when it starts using mutexes.

Thus, add an empty `Gsp` type that is pinned inside `Gpu` and
initialized using a pin initializer. This sets the constraint we need to
observe from the start, and could spare us some costly refactoring down
the road.

Then, move the code related to GSP boot to the `gsp::boot` module, as
part of the `Gsp` implementation.

Doing so allows us to make `Gpu::new` return a fallible `impl PinInit`
instead of a `Result.` This is more idiomatic when working with pinned
objects, and sets up the pinned initialization pattern we want to
preserve as the code grows more complex.

Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250913-nova_firmware-v6-2-9007079548b0@nvidia.com
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
2025-09-13 23:17:21 +09:00