xref: /openbmc/qemu/rust/hw/char/pl011/src/memory_ops.rs (revision 95e82f9b)
1 // Copyright 2024, Linaro Limited
2 // Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
3 // SPDX-License-Identifier: GPL-2.0-or-later
4 
5 use core::{mem::MaybeUninit, ptr::NonNull};
6 
7 use qemu_api::bindings::*;
8 
9 use crate::device::PL011State;
10 
11 pub static PL011_OPS: MemoryRegionOps = MemoryRegionOps {
12     read: Some(pl011_read),
13     write: Some(pl011_write),
14     read_with_attrs: None,
15     write_with_attrs: None,
16     endianness: device_endian::DEVICE_NATIVE_ENDIAN,
17     valid: unsafe { MaybeUninit::<MemoryRegionOps__bindgen_ty_1>::zeroed().assume_init() },
18     impl_: MemoryRegionOps__bindgen_ty_2 {
19         min_access_size: 4,
20         max_access_size: 4,
21         ..unsafe { MaybeUninit::<MemoryRegionOps__bindgen_ty_2>::zeroed().assume_init() }
22     },
23 };
24 
25 #[no_mangle]
26 unsafe extern "C" fn pl011_read(
27     opaque: *mut core::ffi::c_void,
28     addr: hwaddr,
29     size: core::ffi::c_uint,
30 ) -> u64 {
31     assert!(!opaque.is_null());
32     let mut state = unsafe { NonNull::new_unchecked(opaque.cast::<PL011State>()) };
33     let val = unsafe { state.as_mut().read(addr, size) };
34     match val {
35         std::ops::ControlFlow::Break(val) => val,
36         std::ops::ControlFlow::Continue(val) => {
37             // SAFETY: self.char_backend is a valid CharBackend instance after it's been
38             // initialized in realize().
39             let cb_ptr = unsafe { core::ptr::addr_of_mut!(state.as_mut().char_backend) };
40             unsafe { qemu_chr_fe_accept_input(cb_ptr) };
41 
42             val
43         }
44     }
45 }
46 
47 #[no_mangle]
48 unsafe extern "C" fn pl011_write(
49     opaque: *mut core::ffi::c_void,
50     addr: hwaddr,
51     data: u64,
52     _size: core::ffi::c_uint,
53 ) {
54     unsafe {
55         assert!(!opaque.is_null());
56         let mut state = NonNull::new_unchecked(opaque.cast::<PL011State>());
57         state.as_mut().write(addr, data)
58     }
59 }
60