Commit Graph

155 Commits

Author SHA1 Message Date
Alice Ryhl
77b686f688 gpu: nova-core: make formatting compatible with rust tree
Commit 38b7cc448a ("gpu: nova-core: implement Display for Spec") in
drm-rust-next introduced some usage of the Display trait, but the
Display trait is being modified in the rust tree this cycle. Thus, to
avoid conflicts with the Rust tree, tweak how the formatting machinery
is used in a way where it works both with and without the changes in the
Rust tree.

Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20251117-nova-fmt-rust-v1-1-651ca28cd98f@google.com
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
2025-11-17 12:56:36 +00:00
John Hubbard
ce89e3e019 gpu: nova-core: provide a clear error report for unsupported GPUs
Pass in a PCI device to Spec::new(), and provide a Display
implementation for boot42, in order to provide a clear, concise report
of what happened: the driver read NV_PMC_BOOT42, and found that the GPU
is not supported.

For very old GPUs (older than Fermi), the driver still returns ENODEV,
but it does so without a driver-specific dmesg report. That is exactly
appropriate, because if such a GPU is installed, it can only be
supported by Nouveau. And if so, the user is not helped by additional
error messages from Nova.

Here's the full dmesg output for a Blackwell (not yet supported) GPU:

NovaCore 0000:01:00.0: Probe Nova Core GPU driver.
NovaCore 0000:01:00.0: Unsupported chipset: boot42 = 0x1b2a1000 (architecture 0x1b, implementation 0x2)
NovaCore 0000:01:00.0: probe with driver NovaCore failed with error -524

Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Timur Tabi <ttabi@nvidia.com>
Cc: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
[acourbot@nvidia.com: fix commit log with ENODEV (not ENOTSUPP) error
code for unsupported GPUs.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251115010923.1192144-5-jhubbard@nvidia.com>
2025-11-15 23:11:28 +09:00
John Hubbard
0ecc08e2c4 gpu: nova-core: add boot42 support for next-gen GPUs
NVIDIA GPUs are moving away from using NV_PMC_BOOT_0 to contain
architecture and revision details, and will instead use NV_PMC_BOOT_42
in the future. NV_PMC_BOOT_0 will contain a specific set of values
that will mean "go read NV_PMC_BOOT_42 instead".

Change the selection logic in Nova so that it will claim Turing and
later GPUs. This will work for the foreseeable future, without any
further code changes here, because all NVIDIA GPUs are considered, from
the oldest supported on Linux (NV04), through the future GPUs.

Add some comment documentation to explain, chronologically, how boot0
and boot42 change with the GPU eras, and how that affects the selection
logic.

Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Timur Tabi <ttabi@nvidia.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
[acourbot@nvidia.com: remove unneeded `From<BOOT_0> for Revision`
implementation.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251115010923.1192144-4-jhubbard@nvidia.com>
2025-11-15 23:11:27 +09:00
John Hubbard
4d980333a6 gpu: nova-core: make Architecture behave as a u8 type
This allows Architecture to be passed into register!() and bitfield!()
macro calls. That in turn requires a default implementation for
Architecture.

This simplifies transforming BOOT0 (and later, BOOT42) register values
into GPU architectures.

Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Timur Tabi <ttabi@nvidia.com>
Suggested-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251115010923.1192144-3-jhubbard@nvidia.com>
2025-11-15 22:57:37 +09:00
John Hubbard
df6137e263 gpu: nova-core: prepare Spec and Revision types for boot0/boot42
Allow a both Revision and Spec to be constructed directly from a
NV_PMC_BOOT_0 register.

Also, slightly enhance the comment about Spec, to be more precise.

Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Timur Tabi <ttabi@nvidia.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251115010923.1192144-2-jhubbard@nvidia.com>
2025-11-15 22:57:37 +09:00
Alistair Popple
13f85988d4 gpu: nova-core: gsp: Retrieve GSP static info to gather GPU information
After GSP initialization is complete, retrieve the static configuration
information from GSP-RM. This information includes GPU name, capabilities,
memory configuration, and other properties. On some GPU variants, it is
also required to do this for initialization to complete.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Co-developed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
[acourbot@nvidia.com: properly abstract the command's bindings, add
relevant methods, make str_from_null_terminated return an Option, fix
size of GPU name array.]
Co-developed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-14-joelagnelf@nvidia.com>
2025-11-15 21:54:18 +09:00
Alistair Popple
0e7d572b4b gpu: nova-core: gsp: Wait for gsp initialization to complete
This adds the GSP init done command to wait for GSP initialization
to complete. Once this command has been received the GSP is fully
operational and will respond properly to normal RPC commands.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Co-developed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
[acourbot@nvidia.com: move new definitions to end of commands.rs, rename
to `wait_gsp_init_done` and remove timeout argument.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-13-joelagnelf@nvidia.com>
2025-11-15 21:54:18 +09:00
Joel Fernandes
774109857b gpu: nova-core: sequencer: Implement core resume operation
Implement core resume operation. This is the last step of the sequencer
resulting in resume of the GSP and proceeding to INIT_DONE stage of GSP
boot.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-12-joelagnelf@nvidia.com>
2025-11-15 21:54:18 +09:00
Joel Fernandes
9641f05223 gpu: nova-core: sequencer: Implement basic core operations
These opcodes implement various falcon-related boot operations: reset,
start, wait-for-halt.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-11-joelagnelf@nvidia.com>
2025-11-15 21:54:18 +09:00
Joel Fernandes
e386680e8d gpu: nova-core: sequencer: Add delay opcode support
Implement a sequencer opcode for delay operations.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-10-joelagnelf@nvidia.com>
2025-11-15 21:54:18 +09:00
Joel Fernandes
2367ce2e9e gpu: nova-core: sequencer: Add register opcodes
These opcodes are used for register write, modify, poll and store (save)
sequencer operations.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
[acourbot@nvidia.com: apply Lyude's suggested fixes.]
Message-ID: <20251114195552.739371-9-joelagnelf@nvidia.com>
2025-11-15 21:54:18 +09:00
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
Joel Fernandes
eaf0989c77 gpu: nova-core: Add bindings required by GSP sequencer
Add several firmware bindings required by GSP sequencer code.

Co-developed-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
[acourbot@nvidia.com: remove a couple stray lines/unwanted comment
changes.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-7-joelagnelf@nvidia.com>
2025-11-15 20:35:50 +09:00
Joel Fernandes
f77be04d00 gpu: nova-core: gsp: Add support for checking if GSP reloaded
During the sequencer process, we need to check if GSP was successfully
reloaded. Add functionality to check for the same.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-6-joelagnelf@nvidia.com>
2025-11-15 20:08:49 +09:00
Joel Fernandes
0f2c8e278e gpu: nova-core: falcon: Move dma_reset functionality into helper
Move dma_reset so we can use it for the upcoming sequencer
functionality.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-5-joelagnelf@nvidia.com>
2025-11-15 20:08:49 +09:00
Joel Fernandes
4f7656f799 gpu: nova-core: falcon: Move mbox functionalities into helper
Move falcon reading/writing to mbox functionality into helper so we can
use it from the sequencer resume flow.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
[acourbot@nvidia.com: make write/read mailbox methods unfallible.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-4-joelagnelf@nvidia.com>
2025-11-15 20:08:49 +09:00
Joel Fernandes
c5c0cfa67a gpu: nova-core: falcon: Move start functionality into separate helper
Move start functionality into a separate helper so we can use it from
the sequencer.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-3-joelagnelf@nvidia.com>
2025-11-15 17:28:03 +09:00
Joel Fernandes
2d981773e1 gpu: nova-core: falcon: Move waiting until halted to a helper
Move the "waiting until halted" functionality into a helper so that we
can use it in the sequencer, which is a separate sequencer operation.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114195552.739371-2-joelagnelf@nvidia.com>
2025-11-15 17:28:03 +09:00
John Hubbard
38b7cc448a gpu: nova-core: implement Display for Spec
Implement Display for Spec. This simplifies the dev_info!() code for
printing banners such as:

    NVIDIA (Chipset: GA104, Architecture: Ampere, Revision: a.1)

Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Timur Tabi <ttabi@nvidia.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251114024109.465136-2-jhubbard@nvidia.com>
2025-11-14 23:39:27 +09:00
Alistair Popple
5949d419c1 gpu: nova-core: gsp: Boot GSP
Boot the GSP to the RISC-V active state. Completing the boot requires
running the CPU sequencer which will be added in a future commit.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-15-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:57 +09:00
Joel Fernandes
945c1eee7d gpu: nova-core: falcon: Add support to write firmware version
This will be needed by both the GSP boot code as well as GSP resume code
in the sequencer.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-14-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:57 +09:00
Joel Fernandes
bb58d1aee6 gpu: nova-core: falcon: Add support to check if RISC-V is active
Add definition for RISCV_CPUCTL register and use it in a new falcon API
to check if the RISC-V core of a Falcon is active. It is required by
the sequencer to know if the GSP's RISCV processor is active.

Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-13-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:57 +09:00
Alistair Popple
19b0a6e7c2 gpu: nova-core: gsp: Add SetRegistry command
Add support for sending the SetRegistry command, which is critical to
GSP initialization.

The RM registry is serialized into a packed format and sent via the
command queue. For now only three parameters which are required to boot
GSP are hardcoded. In the future a kernel module parameter will be added
to enable other parameters to be added.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
[acourbot@nvidia.com: split into its own patch.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-12-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:57 +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
6b5a10dad5 gpu: nova-core: Add zeroable trait to bindings
Derive the Zeroable trait for existing bindgen generated bindings. This
is safe because all bindgen generated types are simple integer types for
which any bit pattern, including all zeros, is valid.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-7-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:56 +09:00
Joel Fernandes
d416035fb6 gpu: nova-core: Add a slice-buffer (sbuffer) datastructure
A data structure that can be used to write across multiple slices which
may be out of order in memory. This lets SBuffer user correctly and
safely write out of memory order, without error-prone tracking of
pointers/offsets.

    let mut buf1 = [0u8; 3];
    let mut buf2 = [0u8; 5];
    let mut sbuffer = SBuffer::new([&mut buf1[..], &mut buf2[..]]);

    let data = b"hello";
    let result = sbuffer.write(data);

Reviewed-by: Lyude Paul <lyude@redhat.com>
Co-developed-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Co-developed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-6-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:56 +09:00
Alistair Popple
41235c40ed gpu: nova-core: gsp: Create wpr metadata
The GSP requires some pieces of metadata to boot. These are passed in a
struct which the GSP transfers via DMA. Create this struct and get a
handle to it for future use when booting the 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-v9-5-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:56 +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
89605daa1e gpu: nova-core: num: add functions to safely convert a const value to a smaller type
There are times where we need to store a constant value defined as a
larger type (e.g. through a binding) into a smaller type, knowing
that the value will fit. Rust, unfortunately, only provides us with the
`as` operator for that purpose, the use of which is discouraged as it
silently strips data.

Extend the `num` module with functions allowing to perform the
conversion infallibly, at compile time.

Example:

    const FOO_VALUE: u32 = 1;

    // `FOO_VALUE` fits into a `u8`, so the conversion is valid.
    let foo = num::u32_to_u8::<{ FOO_VALUE }>();

We are going to use this feature extensively in Nova.

Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
[acourbot@nvidia.com: fix mistake in example pointed out by Mikko.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-3-8ae4058e3c0e@nvidia.com>
2025-11-14 20:25:15 +09:00
Alistair Popple
1101c44241 gpu: nova-core: Set correct DMA mask
Set the correct DMA mask. Without this DMA will fail on some setups.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251110-gsp_boot-v9-2-8ae4058e3c0e@nvidia.com>
2025-11-14 11:05:58 +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
Alexandre Courbot
80b3dc0a5a gpu: nova-core: justify remaining uses of as
There are a few remaining cases where we *do* want to use `as`,
because we specifically want to strip the data that does not fit into
the destination type. Comment these uses to clear confusion about the
intent.

Acked-by: Danilo Krummrich <dakr@kernel.org>
[acourbot@nvidia.com: fix merge conflicts after rebase.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-as-v3-6-6a30c7333ad9@nvidia.com>
2025-11-08 08:22:51 +09:00
Alexandre Courbot
84e2b401bc gpu: nova-core: replace use of as with functions from num
Use the newly-introduced `num` module to replace the use of `as`
wherever it is safe to do. This ensures that a given conversion cannot
lose data if its source or destination type ever changes.

Acked-by: Danilo Krummrich <dakr@kernel.org>
[acourbot@nvidia.com: fix merge conflicts after rebase.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-as-v3-5-6a30c7333ad9@nvidia.com>
2025-11-08 08:22:45 +09:00
Alexandre Courbot
5525ac03ca gpu: nova-core: add functions and traits for lossless integer conversions
The core library's `From` implementations do not cover conversions
that are not portable or future-proof. For instance, even though it is
safe today, `From<usize>` is not implemented for `u64` because of the
possibility to support larger-than-64bit architectures in the future.

However, the kernel supports a narrower set of architectures, and in the
case of Nova we only support 64-bit. This makes it helpful and desirable
to provide more infallible conversions, lest we need to rely on the `as`
keyword and carry the risk of silently losing data.

Thus, introduce a new module `num` that provides safe const functions
performing more conversions allowed by the build target, as well as
`FromSafeCast` and `IntoSafeCast` traits that are just extensions of
`From` and `Into` to conversions that are known to be lossless.

Suggested-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/rust-for-linux/DDK4KADWJHMG.1FUPL3SDR26XF@kernel.org/
Acked-by: Danilo Krummrich <dakr@kernel.org>
[acourbot@nvidia.com: fix merge conflicts after rebase.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-as-v3-4-6a30c7333ad9@nvidia.com>
2025-11-08 08:22:36 +09:00
Daniel del Castillo
3577e265e4 gpu: nova-core: Simplify DmaObject::from_data in nova-core/dma.rs
This patch solves one of the existing mentions of COHA, a task
in the Nova task list about improving the `CoherentAllocation` API.
It uses the `write` method from `CoherentAllocation`.

Signed-off-by: Daniel del Castillo <delcastillodelarosadaniel@gmail.com>
[acourbot@nvidia.com: set prefix to "gpu: nova-core:".]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251104193756.57726-3-delcastillodelarosadaniel@gmail.com>
2025-11-07 23:10:44 +09:00
Daniel del Castillo
571ce401a7 gpu: nova-core: Fix capitalization of some comments
Some comments that already existed didn't start with a capital
letter, this patch fixes that.

Signed-off-by: Daniel del Castillo <delcastillodelarosadaniel@gmail.com>
[acourbot@nvidia.com: set prefix to "gpu: nova-core:".]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251104193756.57726-2-delcastillodelarosadaniel@gmail.com>
2025-11-07 23:10:44 +09:00
Daniel del Castillo
473f778592 gpu: nova-core: Simplify transmute and transmute_mut in fwsec.rs
This patch solves one of the existing mentions of COHA, a task
in the Nova task list about improving the `CoherentAllocation` API.
It uses the new `from_bytes` method from the `FromBytes` trait as
well as the `as_slice` and `as_slice_mut` methods from
`CoherentAllocation`.

Signed-off-by: Daniel del Castillo <delcastillodelarosadaniel@gmail.com>
[acourbot@nvidia.com: set prefix to "gpu: nova-core:".]
[acourbot@nvidia.com: fix merge conflict after imports refactor.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251104193756.57726-1-delcastillodelarosadaniel@gmail.com>
2025-11-07 23:10:44 +09:00
John Hubbard
173c99b85a gpu: nova-core: apply the one "use" item per line policy
As per [1], we need one "use" item per line, in order to reduce merge
conflicts. Furthermore, we need a trailing ", //" in order to tell
rustfmt(1) to leave it alone.

This does that for the entire nova-core driver.

[1] https://docs.kernel.org/rust/coding-guidelines.html#imports

Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
[acourbot@nvidia.com: remove imports already in prelude as pointed out
by Danilo.]
[acourbot@nvidia.com: remove a few unneeded trailing `//`.]
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251107021006.434109-1-jhubbard@nvidia.com>
2025-11-07 23:10:44 +09:00
Alexandre Courbot
ade19c5060 gpu: nova-core: vbios: use FromBytes for NpdeStruct
Use `from_bytes_copy_prefix` to create `NpdeStruct` instead of building
it ourselves from the bytes stream. This lets us remove a few array
accesses and results in shorter code.

Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-vbios-frombytes-v1-5-ac441ebc1de3@nvidia.com>
2025-11-05 20:29:47 +09:00
Alexandre Courbot
46768644a1 gpu: nova-core: vbios: use FromBytes for BitHeader
Use `from_bytes_copy_prefix` to create `BitHeader` instead of building
it ourselves from the bytes stream. This lets us remove a few array
accesses and results in shorter code.

Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-vbios-frombytes-v1-4-ac441ebc1de3@nvidia.com>
2025-11-05 20:29:47 +09:00
Alexandre Courbot
56bb4b17a6 gpu: nova-core: vbios: use FromBytes for PcirStruct
Use `from_bytes_copy_prefix` to create `PcirStruct` instead of building
it ourselves from the bytes stream. This lets us remove a few array
accesses and results in shorter code.

Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-vbios-frombytes-v1-3-ac441ebc1de3@nvidia.com>
2025-11-05 20:29:47 +09:00
Alexandre Courbot
7f74842d95 gpu: nova-core: vbios: use FromBytes for PmuLookupTable header
Use `from_bytes_copy_prefix` to create the `PmuLookupTable` header
instead of building it ourselves from the bytes stream. This lets us
remove a few `as` conversions and array accesses.

Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-vbios-frombytes-v1-2-ac441ebc1de3@nvidia.com>
2025-11-05 20:29:47 +09:00
Alexandre Courbot
6553a8f168 gpu: nova-core: use try_from instead of as for u32 conversions
There are a few situations in the driver where we convert a `usize` into
a `u32` using `as`. Even though most of these are obviously correct, use
`try_from` and let the compiler optimize wherever it is safe to do so.

Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-as-v3-3-6a30c7333ad9@nvidia.com>
2025-11-04 13:26:54 +09:00
Alexandre Courbot
505c3ec507 gpu: nova-core: vbios: do not use as when comparing BiosImageType
Use the `image_type` method and compare its result to avoid using `as`.

Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-as-v3-2-6a30c7333ad9@nvidia.com>
2025-11-04 13:26:26 +09:00
Alexandre Courbot
9a3c2f8a4f gpu: nova-core: replace as with from conversions where possible
The `as` operator is best avoided as it silently drops bits if the
destination type is smaller that the source.

For data types where this is clearly not the case, use `from` to
unambiguously signal that these conversions are lossless.

Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-as-v3-1-6a30c7333ad9@nvidia.com>
2025-10-30 10:35:34 +09:00
Alexandre Courbot
ca16b15e78 gpu: nova-core: bitfield: remove BitOr implementation
Using this operand can produce invalid values. It also doesn't bring
any benefit as one can use the builder pattern to assemble a new value.

Reported-by: Edwin Peer <epeer@nvidia.com>
Link: https://lore.kernel.org/rust-for-linux/F3853912-2C1C-4F9B-89B0-3168689F35B3@nvidia.com/
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251022-nova-bitfield-v1-3-73bc0988667b@nvidia.com>
2025-10-25 13:16:31 +09:00
Alexandre Courbot
e6b8932b93 gpu: nova-core: bitfield: simplify expression
The shift is more easily expressed by the index of the lowest bit of the
field.

Reported-by: Edwin Peer <epeer@nvidia.com>
Link: https://lore.kernel.org/rust-for-linux/F3853912-2C1C-4F9B-89B0-3168689F35B3@nvidia.com/
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251022-nova-bitfield-v1-2-73bc0988667b@nvidia.com>
2025-10-25 13:16:31 +09:00
Alexandre Courbot
fa08ec789f gpu: nova-core: bitfield: simplify condition
This condition was uselessly convoluted.

Reported-by: Edwin Peer <epeer@nvidia.com>
Link: https://lore.kernel.org/rust-for-linux/F3853912-2C1C-4F9B-89B0-3168689F35B3@nvidia.com/
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251022-nova-bitfield-v1-1-73bc0988667b@nvidia.com>
2025-10-25 13:16:31 +09:00