Ordering nits, changing target

.cargo/config.toml

@@ -1,7 +1,7 @@
 # .cargo/config.toml
 
 [build]
-target = "riscv64imac-unknown-none-elf"
+target = "riscv64gc-unknown-none-elf"
 
 # Options for riscv32 (not currently in use)
 # 
@@ -15,7 +15,7 @@ target = "riscv64imac-unknown-none-elf"
 #   -serial mon:stdio
 #   -bios """
 
-[target.riscv64imac-unknown-none-elf]
+[target.riscv64gc-unknown-none-elf]
 runner = """ qemu-system-riscv64
   -cpu rv64
   -smp 4

src/main.rs

@@ -18,7 +18,7 @@ core::arch::global_asm!(include_str!("entry.s"));
 #[allow(unreachable_code)]
 unsafe extern "C" fn start() {
     use core::arch::asm;
-    use riscv::register::{mstatus, pmpaddr0, satp, sie, sstatus};
+    use riscv::register::{mstatus, satp, sie, sstatus};
 
     // Set previous privilege for all harts to M-mode, set previous interrupt
     // enable, and set floating-point unit to initial state
@@ -26,6 +26,12 @@ unsafe extern "C" fn start() {
     mstatus::set_mpie();
     mstatus::set_fs(sstatus::FS::Initial);
 
+    // For use with 
+    // asm!(
+    //     "la t1, main",
+    //     "csrw mepc, t1",
+    // );
+
     // Disable paging
     satp::write(0);
 
@@ -38,15 +44,14 @@ unsafe extern "C" fn start() {
     sie::set_stimer();
     sie::set_ssoft();
 
-    // hhhh
-    // pmpaddr0::write(0x3fffffffffffff_usize);
-    // TODO configure PMP
+    // Use PMP to give S-mode full access to memory
+    // pmpaddr0::write(0x3fffffffffffff);
+    // pmpcfg0::write(0xf);
+
     // TODO timer init
 
-    // Trying to figure out why I can't use mret here. Might need
+    // Trying to figure out why I can't use mret here
     // asm!(
-    //     "la t1, main",
-    //     "csrw mepc, t1",
     //     "mret",
     //     options(noreturn),
     // );
@@ -64,7 +69,7 @@ extern "C" fn main() {
             // Disable machine interrupts while initializing
             interrupt::machine::disable();
             console_init();
-            // TODO Write boot message
+            println!("boot: console initiated, setting up paging/processes (TODO)");
 
             // TODO Set up paging
             // TODO Set up processes
@@ -73,6 +78,7 @@ extern "C" fn main() {
             // TODO Set up PLIC
 
             kinit();
+
             unsafe {
                 mstatus::set_mpp(mstatus::MPP::User);
                 mstatus::set_mpie();
@@ -80,6 +86,8 @@ extern "C" fn main() {
                 mstatus::set_fs(sstatus::FS::Initial);
             }
 
+            println!("msg: Hello from hart {}!", hartid());
+
             riscv::asm::fence(); // Emit a fence just in case
         });
 
@@ -92,7 +100,7 @@ extern "C" fn main() {
         INIT_LOCK.wait();
         riscv::asm::fence(); // Emit a fence just in case
         kinit_hart();
-        println!("Hello from hart {}!", hartid());
+        println!("msg: Hello from hart {}!", hartid());
     }
 }
 
@@ -102,7 +110,7 @@ fn console_init() {
 
     // Set up UART and print to console
     uart::init_console(0x1000_0000);
-    println!("Hello from hart {}!", hartid());
+    println!("init: console");
 }
 
 fn kinit() {}