@@ -37,6 +37,14 @@ version = "1.12.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "3dca9240753cf90908d7e4aac30f630662b02aebaa1b58a3cadabdb23385b58b"
+[[package]]
+name = "hpet"
+version = "0.1.0"
+dependencies = [
+ "qemu_api",
+ "qemu_api_macros",
+]
+
[[package]]
name = "itertools"
version = "0.11.0"
@@ -4,6 +4,7 @@ members = [
"qemu-api-macros",
"qemu-api",
"hw/char/pl011",
+ "hw/timer/hpet",
]
[workspace.lints.rust]
@@ -1 +1,2 @@
subdir('char')
+subdir('timer')
new file mode 100644
@@ -0,0 +1,14 @@
+[package]
+name = "hpet"
+version = "0.1.0"
+edition = "2021"
+authors = ["Zhao Liu <zhao1.liu@intel.com>"]
+license = "GPL-2.0-or-later"
+description = "IA-PC High Precision Event Timer emulation in Rust"
+
+[lib]
+crate-type = ["staticlib"]
+
+[dependencies]
+qemu_api = { path = "../../../qemu-api" }
+qemu_api_macros = { path = "../../../qemu-api-macros" }
new file mode 100644
@@ -0,0 +1,18 @@
+_libhpet_rs = static_library(
+ 'hpet',
+ files('src/lib.rs'),
+ override_options: ['rust_std=2021', 'build.rust_std=2021'],
+ rust_abi: 'rust',
+ dependencies: [
+ qemu_api,
+ qemu_api_macros,
+ ],
+)
+
+rust_devices_ss.add(when: 'CONFIG_X_HPET_RUST', if_true: [declare_dependency(
+ link_whole: [_libhpet_rs],
+ # Putting proc macro crates in `dependencies` is necessary for Meson to find
+ # them when compiling the root per-target static rust lib.
+ dependencies: [qemu_api_macros],
+ variables: {'crate': 'hpet'},
+)])
new file mode 100644
@@ -0,0 +1,87 @@
+// Copyright (C) 2024 Intel Corporation.
+// Author(s): Zhao Liu <zhai1.liu@intel.com>
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#![allow(dead_code)]
+
+use qemu_api::{cell::bql_locked, impl_zeroable, zeroable::Zeroable};
+
+// Each HPETState represents a Event Timer Block. The v1 spec supports
+// up to 8 blocks. QEMU only uses 1 block (in PC machine).
+const HPET_MAX_NUM_EVENT_TIMER_BLOCK: usize = 8;
+
+#[repr(C, packed)]
+#[derive(Copy, Clone, Default)]
+pub struct HPETFwEntry {
+ pub event_timer_block_id: u32,
+ pub address: u64,
+ pub min_tick: u16,
+ pub page_prot: u8,
+}
+
+unsafe impl Zeroable for HPETFwEntry {
+ const ZERO: Self = Self {
+ event_timer_block_id: 0,
+ address: 0,
+ min_tick: 0,
+ page_prot: 0,
+ };
+}
+
+#[repr(C, packed)]
+#[derive(Copy, Clone, Default)]
+pub struct HPETFwConfig {
+ pub count: u8,
+ pub hpet: [HPETFwEntry; HPET_MAX_NUM_EVENT_TIMER_BLOCK],
+}
+
+impl_zeroable!(HPETFwConfig);
+
+#[allow(non_upper_case_globals)]
+#[no_mangle]
+pub static mut hpet_fw_cfg: HPETFwConfig = HPETFwConfig {
+ count: u8::MAX,
+ ..Zeroable::ZERO
+};
+
+impl HPETFwConfig {
+ pub(crate) fn assign_hpet_id() -> usize {
+ assert!(bql_locked());
+ // SAFETY: all accesses go through these methods, which guarantee
+ // that the accesses are protected by the BQL.
+ let fw_cfg = unsafe { &mut hpet_fw_cfg };
+
+ if fw_cfg.count == u8::MAX {
+ // first instance
+ fw_cfg.count = 0;
+ }
+
+ if fw_cfg.count == 8 {
+ // TODO: Add error binding: error_setg()
+ panic!("Only 8 instances of HPET is allowed");
+ }
+
+ let id: usize = fw_cfg.count.into();
+ fw_cfg.count += 1;
+ id
+ }
+
+ pub(crate) fn update_hpet_cfg(
+ hpet_id: usize,
+ event_timer_block_id: Option<u32>,
+ address: Option<u64>,
+ ) {
+ assert!(bql_locked());
+ // SAFETY: all accesses go through these methods, which guarantee
+ // that the accesses are protected by the BQL.
+ let fw_cfg = unsafe { &mut hpet_fw_cfg };
+
+ if let Some(e) = event_timer_block_id {
+ fw_cfg.hpet[hpet_id].event_timer_block_id = e;
+ }
+
+ if let Some(a) = address {
+ fw_cfg.hpet[hpet_id].address = a;
+ }
+ }
+}
new file mode 100644
@@ -0,0 +1,13 @@
+// Copyright (C) 2024 Intel Corporation.
+// Author(s): Zhao Liu <zhai1.liu@intel.com>
+// SPDX-License-Identifier: GPL-2.0-or-later
+//
+// HPET QEMU Device Model
+//
+// This library implements a device model for the IA-PC HPET (High
+// Precision Event Timers) device in QEMU.
+//
+
+#![deny(unsafe_op_in_unsafe_fn)]
+
+pub mod fw_cfg;
new file mode 100644
@@ -0,0 +1 @@
+subdir('hpet')
@@ -56,6 +56,7 @@ pub unsafe trait Zeroable: Default {
/// ## Differences with `core::mem::zeroed`
///
/// `const_zero` zeroes padding bits, while `core::mem::zeroed` doesn't
+#[macro_export]
macro_rules! const_zero {
// This macro to produce a type-generic zero constant is taken from the
// const_zero crate (v0.1.1):
@@ -77,10 +78,11 @@ union TypeAsBytes {
}
/// A wrapper to implement the `Zeroable` trait through the `const_zero` macro.
+#[macro_export]
macro_rules! impl_zeroable {
($type:ty) => {
- unsafe impl Zeroable for $type {
- const ZERO: Self = unsafe { const_zero!($type) };
+ unsafe impl $crate::zeroable::Zeroable for $type {
+ const ZERO: Self = unsafe { $crate::const_zero!($type) };
}
};
}
Define HPETFwEntry structure with the same memory layout as hpet_fw_entry in C. Further, define the global hpet_cfg variable in Rust which is the same as the C version. This hpet_cfg variable in Rust will replace the C version one and allows both Rust code and C code to access it. The Rust version of hpet_cfg is self-contained, avoiding unsafe access to C code. Signed-off-by: Zhao Liu <zhao1.liu@intel.com> --- Changes since RFC: * hpet_fw_cfg doesn't need a BqlRefCell. --- rust/Cargo.lock | 8 +++ rust/Cargo.toml | 1 + rust/hw/meson.build | 1 + rust/hw/timer/hpet/Cargo.toml | 14 +++++ rust/hw/timer/hpet/meson.build | 18 +++++++ rust/hw/timer/hpet/src/fw_cfg.rs | 87 ++++++++++++++++++++++++++++++++ rust/hw/timer/hpet/src/lib.rs | 13 +++++ rust/hw/timer/meson.build | 1 + rust/qemu-api/src/zeroable.rs | 6 ++- 9 files changed, 147 insertions(+), 2 deletions(-) create mode 100644 rust/hw/timer/hpet/Cargo.toml create mode 100644 rust/hw/timer/hpet/meson.build create mode 100644 rust/hw/timer/hpet/src/fw_cfg.rs create mode 100644 rust/hw/timer/hpet/src/lib.rs create mode 100644 rust/hw/timer/meson.build