xref: /qemu/rust/qemu-api/src/sysbus.rs (revision 9c9a6a889cb3589779b019a343892aa0e9bdb254)
1 // Copyright 2024 Red Hat, Inc.
2 // Author(s): Paolo Bonzini <pbonzini@redhat.com>
3 // SPDX-License-Identifier: GPL-2.0-or-later
4 
5 //! Bindings to access `sysbus` functionality from Rust.
6 
7 use std::{ffi::CStr, ptr::addr_of_mut};
8 
9 pub use bindings::{SysBusDevice, SysBusDeviceClass};
10 
11 use crate::{
12     bindings,
13     cell::bql_locked,
14     irq::{IRQState, InterruptSource},
15     memory::MemoryRegion,
16     prelude::*,
17     qdev::{DeviceImpl, DeviceState},
18     qom::Owned,
19 };
20 
21 unsafe impl ObjectType for SysBusDevice {
22     type Class = SysBusDeviceClass;
23     const TYPE_NAME: &'static CStr =
24         unsafe { CStr::from_bytes_with_nul_unchecked(bindings::TYPE_SYS_BUS_DEVICE) };
25 }
26 qom_isa!(SysBusDevice: DeviceState, Object);
27 
28 // TODO: add virtual methods
29 pub trait SysBusDeviceImpl: DeviceImpl + IsA<SysBusDevice> {}
30 
31 impl SysBusDeviceClass {
32     /// Fill in the virtual methods of `SysBusDeviceClass` based on the
33     /// definitions in the `SysBusDeviceImpl` trait.
34     pub fn class_init<T: SysBusDeviceImpl>(self: &mut SysBusDeviceClass) {
35         self.parent_class.class_init::<T>();
36     }
37 }
38 
39 /// Trait for methods of [`SysBusDevice`] and its subclasses.
40 pub trait SysBusDeviceMethods: ObjectDeref
41 where
42     Self::Target: IsA<SysBusDevice>,
43 {
44     /// Expose a memory region to the board so that it can give it an address
45     /// in guest memory.  Note that the ordering of calls to `init_mmio` is
46     /// important, since whoever creates the sysbus device will refer to the
47     /// region with a number that corresponds to the order of calls to
48     /// `init_mmio`.
49     fn init_mmio(&self, iomem: &MemoryRegion) {
50         assert!(bql_locked());
51         unsafe {
52             bindings::sysbus_init_mmio(self.as_mut_ptr(), iomem.as_mut_ptr());
53         }
54     }
55 
56     /// Expose an interrupt source outside the device as a qdev GPIO output.
57     /// Note that the ordering of calls to `init_irq` is important, since
58     /// whoever creates the sysbus device will refer to the interrupts with
59     /// a number that corresponds to the order of calls to `init_irq`.
60     fn init_irq(&self, irq: &InterruptSource) {
61         assert!(bql_locked());
62         unsafe {
63             bindings::sysbus_init_irq(self.as_mut_ptr(), irq.as_ptr());
64         }
65     }
66 
67     // TODO: do we want a type like GuestAddress here?
68     fn mmio_map(&self, id: u32, addr: u64) {
69         assert!(bql_locked());
70         let id: i32 = id.try_into().unwrap();
71         unsafe {
72             bindings::sysbus_mmio_map(self.as_mut_ptr(), id, addr);
73         }
74     }
75 
76     // Owned<> is used here because sysbus_connect_irq (via
77     // object_property_set_link) adds a reference to the IRQState,
78     // which can prolong its life
79     fn connect_irq(&self, id: u32, irq: &Owned<IRQState>) {
80         assert!(bql_locked());
81         let id: i32 = id.try_into().unwrap();
82         let irq: &IRQState = irq;
83         unsafe {
84             bindings::sysbus_connect_irq(self.as_mut_ptr(), id, irq.as_mut_ptr());
85         }
86     }
87 
88     fn sysbus_realize(&self) {
89         // TODO: return an Error
90         assert!(bql_locked());
91         unsafe {
92             bindings::sysbus_realize(self.as_mut_ptr(), addr_of_mut!(bindings::error_fatal));
93         }
94     }
95 }
96 
97 impl<R: ObjectDeref> SysBusDeviceMethods for R where R::Target: IsA<SysBusDevice> {}
98