todo: 再补充部分系统重置逻辑

Signed-off-by: YdrMaster <ydrml@hotmail.com>

Author: YdrMaster

Cargo.lock

@@ -7,7 +7,7 @@ readme = "README.md"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-rustsbi = { git = "https://github.com/YdrMaster/rustsbi.git", rev = "2aeecdf" }
+rustsbi = { git = "https://github.com/YdrMaster/rustsbi.git", rev = "bd3c092" }
 riscv = "0.8"
 spin = "0.9"
 r0 = "1"

rustsbi-qemu/Cargo.toml

@@ -1,7 +1,13 @@
 use crate::{clint, hart_id, qemu_hsm::QemuHsm, Supervisor};
 use riscv::register::{mstatus, mtval, scause, sepc, stval, stvec};
 
-pub(crate) fn execute_supervisor(hsm: &QemuHsm, supervisor: Supervisor) {
+#[repr(usize)]
+pub(crate) enum Operation {
+    Stop = 0,
+    SystemReset = usize::MAX,
+}
+
+pub(crate) fn execute_supervisor(hsm: &QemuHsm, supervisor: Supervisor) -> Operation {
     use core::arch::asm;
     use riscv::register::{medeleg, mie};
 
@@ -50,30 +56,9 @@ pub(crate) fn execute_supervisor(hsm: &QemuHsm, supervisor: Supervisor) {
                 }
             }
             T::Exception(E::SupervisorEnvCall) => {
-                use rustsbi::spec::{binary::*, hsm::*, srst::*};
-                let param = [ctx.a(0), ctx.a(1), ctx.a(2), ctx.a(3), ctx.a(4), ctx.a(5)];
-                let ans = rustsbi::ecall(ctx.a(7), ctx.a(6), param);
-                if ans.error == RET_SUCCESS {
-                    match ctx.a(7) {
-                        EID_HSM => match ctx.a(6) {
-                            HART_STOP => return,
-                            HART_SUSPEND
-                                if ctx.a(0) == HART_SUSPEND_TYPE_NON_RETENTIVE as usize =>
-                            {
-                                return
-                            }
-                            _ => {}
-                        },
-                        EID_SRST => match ctx.a(0) as u32 {
-                            RESET_TYPE_COLD_REBOOT | RESET_TYPE_WARM_REBOOT => todo!(),
-                            _ => {}
-                        },
-                        _ => {}
-                    }
+                if let Some(op) = ctx.handle_ecall() {
+                    return op;
                 }
-                *ctx.a_mut(0) = ans.error;
-                *ctx.a_mut(1) = ans.value;
-                ctx.mepc = ctx.mepc.wrapping_add(4);
             }
             T::Exception(E::IllegalInstruction) => {
                 use riscv::register::scause::{Exception as E, Trap as T};
@@ -149,7 +134,61 @@ impl Context {
         self.x_mut(n + 10)
     }
 
-    pub(super) fn do_transfer_trap(&mut self, cause: scause::Trap) {
+    fn handle_ecall(&mut self) -> Option<Operation> {
+        use rustsbi::spec::{binary::*, hsm::*, srst::*};
+        let extension = self.a(7);
+        let function = self.a(6);
+        let ans = rustsbi::ecall(
+            extension,
+            function,
+            [
+                self.a(0),
+                self.a(1),
+                self.a(2),
+                self.a(3),
+                self.a(4),
+                self.a(5),
+            ],
+        );
+        // 判断导致退出执行流程的调用
+        if ans.error == RET_SUCCESS {
+            match extension {
+                // 核状态
+                EID_HSM => match function {
+                    HART_STOP => return Some(Operation::Stop),
+                    HART_SUSPEND
+                        if matches!(
+                            u32::try_from(self.a(0)),
+                            Ok(HART_SUSPEND_TYPE_NON_RETENTIVE)
+                        ) =>
+                    {
+                        return Some(Operation::Stop);
+                    }
+                    _ => {}
+                },
+                // 系统重置
+                EID_SRST => match function {
+                    SYSTEM_RESET
+                        if matches!(
+                            u32::try_from(self.a(0)),
+                            Ok(RESET_TYPE_COLD_REBOOT) | Ok(RESET_TYPE_WARM_REBOOT)
+                        ) =>
+                    {
+                        return Some(Operation::SystemReset)
+                    }
+                    _ => {}
+                },
+
+                _ => {}
+            }
+        }
+        *self.a_mut(0) = ans.error;
+        *self.a_mut(1) = ans.value;
+        self.mepc = self.mepc.wrapping_add(4);
+        None
+    }
+
+    fn do_transfer_trap(&mut self, cause: scause::Trap) {
         unsafe {
             // 向 S 转发陷入
             mstatus::set_mpp(mstatus::MPP::Supervisor);

rustsbi-qemu/src/execute.rs

@@ -3,9 +3,6 @@
 #![no_main]
 #![deny(warnings)]
 
-#[macro_use] // for print
-extern crate rustsbi;
-
 mod clint;
 mod device_tree;
 mod execute;
@@ -14,6 +11,15 @@ mod ns16550a;
 mod qemu_hsm;
 mod qemu_test;
 
+#[macro_use] // for print
+extern crate rustsbi;
+
+use constants::*;
+use core::sync::atomic::{AtomicBool, Ordering::AcqRel};
+use device_tree::BoardInfo;
+use execute::Operation;
+use spin::Once;
+
 mod constants {
     /// 特权软件入口。
     pub(crate) const SUPERVISOR_ENTRY: usize = 0x8020_0000;
@@ -25,8 +31,6 @@ mod constants {
     pub(crate) const LEN_STACK_SBI: usize = LEN_STACK_PER_HART * NUM_HART_MAX;
 }
 
-use constants::*;
-
 /// 特权软件信息。
 struct Supervisor {
     start_addr: usize,
@@ -60,24 +64,27 @@ fn panic(info: &core::panic::PanicInfo) -> ! {
 #[naked]
 #[link_section = ".text.entry"]
 #[export_name = "_start"]
-unsafe extern "C" fn entry(hartid: usize, opaque: usize) -> ! {
+unsafe extern "C" fn entry() -> ! {
     #[link_section = ".bss.uninit"]
     static mut SBI_STACK: [u8; LEN_STACK_SBI] = [0; LEN_STACK_SBI];
 
-    core::arch::asm!("
-           csrw mie,  zero
-           csrr  a0,  mhartid
-           la    sp, {stack}
+    core::arch::asm!(
+        // 关中断
+        "  csrw mie,  zero",
+        // 设置栈
+        "  la    sp, {stack}
            li    t0, {per_hart_stack_size}
-           addi  t1,  a0,  1
+           csrr  t1,  mhartid
+           addi  t1,  t1,  1
         1: add   sp,  sp, t0
            addi  t1,  t1, -1
-           bnez  t1,  1b
-           call {rust_main}
-           call {finalize}
+           bnez  t1,  1b",
+        "  call {rust_main}",
+        // 清理，然后重启或等待
+        "  call {finalize}
+           bnez  a0,  _start
         1: wfi
-           j     1b
-        ",
+           j     1b",
         per_hart_stack_size = const LEN_STACK_PER_HART,
         stack               =   sym SBI_STACK,
         rust_main           =   sym rust_main,
@@ -104,14 +111,10 @@ extern "C" fn early_trap() -> ! {
     }
 }
 
-use core::sync::atomic::{AtomicBool, Ordering::AcqRel};
-use device_tree::BoardInfo;
-use spin::Once;
-
 static HSM: Once<qemu_hsm::QemuHsm> = Once::new();
 
 /// rust 入口。
-extern "C" fn rust_main(_hartid: usize, opaque: usize) {
+extern "C" fn rust_main(_hartid: usize, opaque: usize) -> Operation {
     unsafe { set_mtvec(early_trap as _) };
 
     #[link_section = ".bss.uninit"] // 以免清零
@@ -168,22 +171,38 @@ extern "C" fn rust_main(_hartid: usize, opaque: usize) {
 
     let hsm = HSM.wait();
     if let Some(supervisor) = hsm.take_supervisor() {
+        use execute::*;
         // 设置并打印 pmp
         set_pmp(BOARD_INFO.wait());
         if !CSR_PRINT.swap(true, AcqRel) {
             hart_csr_utils::print_pmps();
         }
-        execute::execute_supervisor(hsm, supervisor);
+        execute_supervisor(hsm, supervisor)
+    } else {
+        Operation::Stop
     }
 }
 
 /// 准备好不可恢复休眠或关闭
 ///
 /// 在隔离的环境（汇编）调用，以确保 main 中使用的堆资源完全释放。
 /// （只是作为示例，因为这个版本完全不使用堆）
-extern "C" fn finalize() {
-    HSM.wait().finallize_before_stop();
-    unsafe { riscv::interrupt::enable() };
+unsafe extern "C" fn finalize(op: Operation) -> ! {
+    match op {
+        Operation::Stop => {
+            HSM.wait().finallize_before_stop();
+            riscv::interrupt::enable();
+            // 从中断响应直接回 entry
+            loop {
+                riscv::asm::wfi();
+            }
+        }
+        Operation::SystemReset => {
+            // TODO 等待其他核关闭
+            // 直接回 entry
+            entry()
+        }
+    }
 }
 
 /// 清零 bss 段。