kernel/linux.git/drivers/gpu/nova-core/gsp.rs, branch v7.1

gpu: nova-core: use sized array for GSP log buffers

2026-03-27T20:48:23+00:00

Switch LogBuffer from Coherent<[u8]> (unsized) to Coherent<[u8; LOG_BUFFER_SIZE]> (sized). The buffer size is a compile-time constant (RM_LOG_BUFFER_NUM_PAGES * GSP_PAGE_SIZE), so a fixed-size array is more precise and avoids the need for the runtime length parameter of zeroed_slice(). Acked-by: Gary Guo Reviewed-by: Alexandre Courbot Link: https://patch.msgid.link/20260325003921.3420-3-dakr@kernel.org Signed-off-by: Danilo Krummrich

gpu: nova-core: create GSP-RM logging buffers debugfs entries

2026-03-25T00:24:26+00:00

Create read-only debugfs entries for LOGINIT, LOGRM, and LOGINTR, which are the three primary printf logging buffers from GSP-RM. LOGPMU will be added at a later date, as it requires support for its RPC message first. This patch uses the `pin_init_scope` feature to create the entries. `pin_init_scope` solves the lifetime issue over the `DEBUGFS_ROOT` reference by delaying its acquisition until the time the entry is actually initialized. Co-developed-by: Alexandre Courbot Signed-off-by: Alexandre Courbot Signed-off-by: Timur Tabi Tested-by: John Hubbard Tested-by: Eliot Courtney Link: https://patch.msgid.link/20260319212658.2541610-7-ttabi@nvidia.com [ Rebase onto Coherent changes. - Danilo ] Signed-off-by: Danilo Krummrich

gpu: nova-core: convert to new dma::Coherent API

2026-03-23T21:36:00+00:00

Remove all usages of dma::CoherentAllocation and use the new dma::Coherent type instead. Signed-off-by: Gary Guo Co-developed-by: Danilo Krummrich Signed-off-by: Danilo Krummrich Reviewed-by: Alexandre Courbot Link: https://patch.msgid.link/20260320194626.36263-9-dakr@kernel.org Signed-off-by: Danilo Krummrich

gpu: nova-core: convert Gsp::new() to use CoherentBox

2026-03-23T21:36:00+00:00

Convert libos (LibosMemoryRegionInitArgument) and rmargs (GspArgumentsPadded) to use CoherentBox / Coherent::init() and simplify the initialization. This also avoids separate initialization on the stack. Reviewed-by: Gary Guo Reviewed-by: Alexandre Courbot Link: https://patch.msgid.link/20260320194626.36263-8-dakr@kernel.org Signed-off-by: Danilo Krummrich

gpu: nova-core: gsp: make `Cmdq` a pinned type

2026-03-18T12:53:14+00:00

Make `Cmdq` a pinned type. This is needed to use Mutex, which is needed to add locking to `Cmdq`. Reviewed-by: Zhi Wang Tested-by: Zhi Wang Signed-off-by: Eliot Courtney Link: https://patch.msgid.link/20260318-cmdq-locking-v5-4-18b37e3f9069@nvidia.com Signed-off-by: Alexandre Courbot

gpu: nova-core: fix stack overflow in GSP memory allocation

2026-03-10T17:29:14+00:00

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 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: f38b4f105cfc ("gpu: nova-core: Create initial Gsp") Acked-by: Alexandre Courbot Signed-off-by: Tim Kovalenko 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

rust: dma: use pointer projection infra for `dma_{read,write}` macro

2026-03-07T22:06:20+00:00

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: ad2907b4e308 ("rust: add dma coherent allocator abstraction") Reviewed-by: Benno Lossin Signed-off-by: Gary Guo 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

gpu: nova-core: align LibosMemoryRegionInitArgument size to page size

2026-01-24T01:48:59+00:00

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 Reviewed-by: Gary Guo Acked-by: Danilo Krummrich Link: https://patch.msgid.link/20260122222848.2555890-12-ttabi@nvidia.com [acourbot@nvidia.com: GspArgumentsAligned -> GspArgumentsPadded] Signed-off-by: Alexandre Courbot

gpu: nova-core: gsp: move appropriate code into pin initializer

2025-12-29T16:54:32+00:00

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 Link: https://patch.msgid.link/20251218155239.25243-5-dakr@kernel.org Signed-off-by: Danilo Krummrich

gpu: nova-core: gsp: get rid of redundant Result in Gsp::new()

2025-12-29T16:54:31+00:00

In Gsp::new(), utilize pin_init_scope() to get rid of the Result in the returned Result> which is unnecessarily redundant. Reviewed-by: Joel Fernandes Link: https://patch.msgid.link/20251218155239.25243-4-dakr@kernel.org Signed-off-by: Danilo Krummrich