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| author | Richard Henderson <richard.henderson@linaro.org> | 2025-09-18 07:05:58 -0700 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2025-09-18 07:05:59 -0700 |
| commit | ccafa85a97e38698b798115bba6c18c849846e25 (patch) | |
| tree | a7d4941f050d4b621cffe2a71657a1bd39c35d4b /rust/hw/core/src/irq.rs | |
| parent | f0007b7f03e2d7fc33e71c3a582f2364c51a226b (diff) | |
| parent | 00c0911c68e5bd664de1a261b74c390f4c0be83d (diff) | |
| download | focaccia-qemu-ccafa85a97e38698b798115bba6c18c849846e25.tar.gz focaccia-qemu-ccafa85a97e38698b798115bba6c18c849846e25.zip | |
Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging
* cpu-exec: more cleanups to CPU loop exits * python: bump bundled Meson to 1.9.0 * rust: require Rust 1.83.0 * rust: temporarily remove from Ubuntu CI * rust: vmstate: convert to use builder pattern * rust: split "qemu-api" crate * rust: rename qemu_api_macros -> qemu_macros * rust: re-export qemu macros from other crates * x86: fix functional test failure for Xen emulation * x86: cleanups # -----BEGIN PGP SIGNATURE----- # # iQFIBAABCgAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmjK6ZsUHHBib256aW5p # QHJlZGhhdC5jb20ACgkQv/vSX3jHroNBKwf/aadInCT4vASOfpxbwZgYfYgR2m2m # BJE9oYKxZJ6MlEOU/1Wfywf9fg4leMSh3XxkDKkEIL19yS6emwin8n3SNYrdAFn3 # 6u4IIWO4NI1Ht3NKytrqFk9wtbH9pAs/gVHLlnmpMxIqtOtZLumPAKNz8rlantmK # UVDYL3Y0L4pD9i5FK1ObMNpk5AsWNr8Tr64fmb+nTkHutld3sBrEMCLI0+EByGyN # lQ16sLn9PGqHOr210zuQP7wP2T3NCI3YokFSPQrUUL8LZGxRdXoNF4hI4uZDKGdn # UbtRu9EkM052qzfsFMrEw5JSbdxEfIjKlPoFKseMv+aWvNAuximAraD3Vg== # =Lr+x # -----END PGP SIGNATURE----- # gpg: Signature made Wed 17 Sep 2025 10:02:19 AM PDT # gpg: using RSA key F13338574B662389866C7682BFFBD25F78C7AE83 # gpg: issuer "pbonzini@redhat.com" # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [unknown] # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" [unknown] # gpg: WARNING: The key's User ID is not certified with a trusted signature! # gpg: There is no indication that the signature belongs to the owner. # Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1 # Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83 * tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (60 commits) accel/kvm: Set guest_memfd_offset to non-zero value only when guest_memfd is valid accel/kvm: Zero out mem explicitly in kvm_set_user_memory_region() accel/kvm: Switch to check KVM_CAP_GUEST_MEMFD and KVM_CAP_USER_MEMORY2 on VM i386/kvm: Drop KVM_CAP_X86_SMM check in kvm_arch_init() multiboot: Fix the split lock target/i386: Define enum X86ASIdx for x86's address spaces i386/cpu: Enable SMM cpu address space under KVM hpet: guard IRQ handling with BQL rust: do not inline do_init_io rust: meson: remove unnecessary complication in device crates docs: update rust.rst rust: re-export qemu macros from common/qom/hwcore rust: re-export qemu_macros internal helper in "bits" rust: repurpose qemu_api -> tests rust/pl011: drop dependency on qemu_api rust/hpet: drop now unneeded qemu_api dep rust: rename qemu_api_macros -> qemu_macros rust: split "hwcore" crate rust: split "system" crate rust: split "chardev" crate ... Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'rust/hw/core/src/irq.rs')
| -rw-r--r-- | rust/hw/core/src/irq.rs | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/rust/hw/core/src/irq.rs b/rust/hw/core/src/irq.rs new file mode 100644 index 0000000000..e0d7784d97 --- /dev/null +++ b/rust/hw/core/src/irq.rs @@ -0,0 +1,115 @@ +// Copyright 2024 Red Hat, Inc. +// Author(s): Paolo Bonzini <pbonzini@redhat.com> +// SPDX-License-Identifier: GPL-2.0-or-later + +//! Bindings for interrupt sources + +use std::{ + ffi::{c_int, CStr}, + marker::PhantomData, + ptr, +}; + +use bql::BqlCell; +use common::Opaque; +use qom::{prelude::*, ObjectClass}; + +use crate::bindings::{self, qemu_set_irq}; + +/// An opaque wrapper around [`bindings::IRQState`]. +#[repr(transparent)] +#[derive(Debug, common::Wrapper)] +pub struct IRQState(Opaque<bindings::IRQState>); + +/// Interrupt sources are used by devices to pass changes to a value (typically +/// a boolean). The interrupt sink is usually an interrupt controller or +/// GPIO controller. +/// +/// As far as devices are concerned, interrupt sources are always active-high: +/// for example, `InterruptSource<bool>`'s [`raise`](InterruptSource::raise) +/// method sends a `true` value to the sink. If the guest has to see a +/// different polarity, that change is performed by the board between the +/// device and the interrupt controller. +/// +/// Interrupts are implemented as a pointer to the interrupt "sink", which has +/// type [`IRQState`]. A device exposes its source as a QOM link property using +/// a function such as [`crate::sysbus::SysBusDeviceMethods::init_irq`], and +/// initially leaves the pointer to a NULL value, representing an unconnected +/// interrupt. To connect it, whoever creates the device fills the pointer with +/// the sink's `IRQState *`, for example using `sysbus_connect_irq`. Because +/// devices are generally shared objects, interrupt sources are an example of +/// the interior mutability pattern. +/// +/// Interrupt sources can only be triggered under the Big QEMU Lock; `BqlCell` +/// allows access from whatever thread has it. +#[derive(Debug)] +#[repr(transparent)] +pub struct InterruptSource<T = bool> +where + c_int: From<T>, +{ + cell: BqlCell<*mut bindings::IRQState>, + _marker: PhantomData<T>, +} + +// SAFETY: the implementation asserts via `BqlCell` that the BQL is taken +unsafe impl<T> Sync for InterruptSource<T> where c_int: From<T> {} + +impl InterruptSource<bool> { + /// Send a low (`false`) value to the interrupt sink. + pub fn lower(&self) { + self.set(false); + } + + /// Send a high-low pulse to the interrupt sink. + pub fn pulse(&self) { + self.set(true); + self.set(false); + } + + /// Send a high (`true`) value to the interrupt sink. + pub fn raise(&self) { + self.set(true); + } +} + +impl<T> InterruptSource<T> +where + c_int: From<T>, +{ + /// Send `level` to the interrupt sink. + pub fn set(&self, level: T) { + let ptr = self.cell.get(); + // SAFETY: the pointer is retrieved under the BQL and remains valid + // until the BQL is released, which is after qemu_set_irq() is entered. + unsafe { + qemu_set_irq(ptr, level.into()); + } + } + + pub(crate) const fn as_ptr(&self) -> *mut *mut bindings::IRQState { + self.cell.as_ptr() + } + + pub(crate) const fn slice_as_ptr(slice: &[Self]) -> *mut *mut bindings::IRQState { + assert!(!slice.is_empty()); + slice[0].as_ptr() + } +} + +impl Default for InterruptSource { + fn default() -> Self { + InterruptSource { + cell: BqlCell::new(ptr::null_mut()), + _marker: PhantomData, + } + } +} + +unsafe impl ObjectType for IRQState { + type Class = ObjectClass; + const TYPE_NAME: &'static CStr = + unsafe { CStr::from_bytes_with_nul_unchecked(bindings::TYPE_IRQ) }; +} + +qom_isa!(IRQState: Object); |