feat: UART terminal (#7)

* feat: basic terminal

* feat: execute application via terminal

.gitignore

@@ -5,3 +5,4 @@ sd.img
 settings.json
 .DS_Store
 .venv
+.nvimlog

.vscode/launch.json

@@ -58,15 +58,12 @@
       ],
       "preLaunchTask": "Run QEMU wo window"
     },
-
     {
-      "name": "Attach LLDB",
+      "name": "LLDB",
       "type": "lldb",
-      "request": "attach",
+      "request": "launch",
-      "debugServer": 1234,
       "program": "${workspaceFolder}/target/aarch64-unknown-none/debug/nova",
-      "stopOnEntry": true,
+      "preLaunchTask": "Run QEMU wo window"
-      "processCreateCommands": ["gdb-remote localhost:1234"]
     }
   ]
 }

Cargo.lock

@@ -40,12 +40,19 @@ version = "0.2.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f9fbbcab51052fe104eb5e5d351cf728d30a5be1fe14d9be8a3b097481fb97de"
 
+[[package]]
+name = "log"
+version = "0.4.29"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
+
 [[package]]
 name = "nova"
 version = "0.1.0"
 dependencies = [
  "heap",
  "libm",
+ "log",
  "nova_error",
  "paste",
 ]

Cargo.toml

@@ -17,6 +17,7 @@ libm = "0.2.15"
 heap = {path = "workspace/heap"}
 nova_error = {path = "workspace/nova_error"}
 paste = "1.0.15"
+log = "0.4.29"
 
 [workspace]
 

src/aarch64/mmu.rs

@@ -106,6 +106,18 @@ pub enum PhysSource {
 #[repr(align(4096))]
 pub struct PageTable([TableEntry; TABLE_ENTRY_COUNT]);
 
+impl Iterator for PageTable {
+    type Item = VirtAddr;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        for (offset, entity) in self.0.iter().enumerate() {
+            if entity.is_invalid() {
+                return Some(offset);
+            }
+        }
+        None
+    }
+}
 #[no_mangle]
 pub static mut TRANSLATIONTABLE_TTBR0: PageTable = PageTable([TableEntry { value: 0 }; 512]);
 #[no_mangle]
@@ -197,7 +209,7 @@ fn map_range_dynamic(
 
 /// Allocate a singe page.
 pub fn alloc_page(
-    virtual_address: usize,
+    virtual_address: VirtAddr,
     base_table: *mut PageTable,
     additional_flags: u64,
 ) -> Result<(), NovaError> {
@@ -209,6 +221,28 @@ pub fn alloc_page(
     )
 }
 
+/// Allocate a singe page in one block.
+pub fn find_free_kerne_page_in_block(start: VirtAddr) -> Result<VirtAddr, NovaError> {
+    if !start.is_multiple_of(GRANULARITY) {
+        return Err(NovaError::Misalignment);
+    }
+
+    let (off1, off2, _) = virtual_address_to_table_offset(start);
+    let offsets = [off1, off2];
+    let table = unsafe {
+        &mut *navigate_table(
+            core::ptr::addr_of_mut!(TRANSLATIONTABLE_TTBR1),
+            &offsets,
+            true,
+        )?
+    };
+
+    if let Some(virt_addr) = table.next() {
+        return Ok(virt_addr);
+    }
+    Err(NovaError::OutOfMeomory)
+}
+
 /// Allocate a single page at an explicit `physical_address`.
 pub fn alloc_page_explicit(
     virtual_address: usize,

src/config.S

@@ -77,7 +77,7 @@ configure_mmu_el1:
 .align 4
 .global el1_to_el0
 el1_to_el0:
-
+    mov x8, x0
     // Set SPSR_EL1: return to EL0t
     mov x0, #(0b0000)
     msr SPSR_EL1, x0
@@ -93,5 +93,6 @@ el1_to_el0:
 
     isb
 
+    mov x0, x8
     // Return to EL0
     eret

src/configuration/memory_mapping.rs

@@ -19,6 +19,8 @@ pub const EL0_STACK_SIZE: usize = LEVEL2_BLOCK_SIZE * 2;
 pub const MAILBOX_VIRTUAL_ADDRESS: VirtAddr = 0xFFFF_FF81_FFFF_E000;
 pub static mut MAILBOX_PHYSICAL_ADDRESS: Option<PhysAddr> = None;
 
+pub const APPLICATION_TRANSLATION_TABLE_VA: VirtAddr = 0xFFFF_FF81_FE00_0000;
+
 extern "C" {
     static __text_end: u64;
     static __share_end: u64;
@@ -99,6 +101,7 @@ pub fn initialize_mmu_translation_tables() {
     )
     .unwrap();
 
+    // Allocate Mailbox buffer
     {
         let addr = reserve_page();
         unsafe { MAILBOX_PHYSICAL_ADDRESS = Some(addr) };

src/framebuffer.rs

@@ -4,10 +4,8 @@ mod bitmaps;
 
 use bitmaps::BASIC_LEGACY;
 
-use crate::{
+use crate::pi3::mailbox::{read_mailbox, write_mailbox};
-    pi3::mailbox::{read_mailbox, write_mailbox},
+use log::error;
-    println,
-};
 #[repr(align(16))]
 struct Mailbox([u32; 36]);
 
@@ -237,7 +235,7 @@ impl Default for FrameBuffer {
 
         let _ = read_mailbox(8);
         if mailbox.0[1] == 0 {
-            println!("Failed");
+            error!("Mailbox request was not processed!");
         }
 
         mailbox.0[28] &= 0x3FFFFFFF;

src/interrupt_handlers.rs

@@ -2,8 +2,9 @@ use core::arch::asm;
 
 use crate::{
     aarch64::registers::{daif::mask_all, read_esr_el1, read_exception_source_el},
-    get_current_el, println,
+    get_current_el,
 };
+use log::debug;
 
 const INTERRUPT_BASE: u32 = 0x3F00_B000;
 const IRQ_PENDING_BASE: u32 = INTERRUPT_BASE + 0x204;
@@ -66,17 +67,17 @@ unsafe extern "C" fn rust_synchronous_interrupt_no_el_change() {
     mask_all();
 
     let source_el = read_exception_source_el() >> 2;
-    println!("--------Sync Exception in EL{}--------", source_el);
+    debug!("--------Sync Exception in EL{}--------", source_el);
-    println!("No EL change");
+    debug!("No EL change");
-    println!("Current EL: {}", get_current_el());
+    debug!("Current EL: {}", get_current_el());
-    println!("{:?}", EsrElX::from(read_esr_el1()));
+    debug!("{:?}", EsrElX::from(read_esr_el1()));
-    println!("Return register address: {:#x}", read_esr_el1());
+    debug!("Return register address: {:#x}", read_esr_el1());
-    println!("-------------------------------------");
+    debug!("-------------------------------------");
 }
 
-fn set_return_to_kernel_main() {
+fn set_return_to_kernel_loop() {
     unsafe {
-        asm!("ldr x0, =kernel_main", "msr ELR_EL1, x0");
+        asm!("ldr x0, =kernel_loop", "msr ELR_EL1, x0");
         asm!("mov x0, #(0b0101)", "msr SPSR_EL1, x0");
     }
 }

src/interrupt_handlers/irq.rs

@@ -12,9 +12,11 @@ use crate::{
         gpio::{read_gpio_event_detect_status, reset_gpio_event_detect_status},
         uart::clear_uart_interrupt_state,
     },
-    println, read_address, write_address,
+    read_address, write_address,
 };
 use alloc::vec::Vec;
+use log::{debug, info};
+
 struct InterruptHandlers {
     source: IRQSource,
     function: fn(),
@@ -60,9 +62,9 @@ unsafe extern "C" fn rust_irq_handler() {
     if pending_irqs & GPIO_PENDING_BIT_OFFSET != 0 {
         handle_gpio_interrupt();
         let source_el = read_exception_source_el() >> 2;
-        println!("Source EL: {}", source_el);
+        debug!("Source EL: {}", source_el);
-        println!("Current EL: {}", get_current_el());
+        debug!("Current EL: {}", get_current_el());
-        println!("Return register address: {:#x}", read_esr_el1());
+        debug!("Return register address: {:#x}", read_esr_el1());
     }
 
     if let Some(handler_vec) = unsafe { &*core::ptr::addr_of_mut!(INTERRUPT_HANDLERS) } {
@@ -76,7 +78,7 @@ unsafe extern "C" fn rust_irq_handler() {
 }
 
 fn handle_gpio_interrupt() {
-    println!("Interrupt");
+    debug!("GPIO interrupt triggered");
     for i in 0..=53u32 {
         let val = read_gpio_event_detect_status(i);
 
@@ -84,7 +86,7 @@ fn handle_gpio_interrupt() {
             #[allow(clippy::single_match)]
             match i {
                 26 => {
-                    println!("Button Pressed");
+                    info!("Button Pressed");
                 }
                 _ => {}
             }

src/interrupt_handlers/synchronous.rs

@@ -1,11 +1,12 @@
 use crate::{
     aarch64::registers::{daif::mask_all, read_elr_el1, read_esr_el1, read_exception_source_el},
     get_current_el,
-    interrupt_handlers::{set_return_to_kernel_main, EsrElX, TrapFrame},
+    interrupt_handlers::{set_return_to_kernel_loop, EsrElX, TrapFrame},
     pi3::mailbox,
-    println,
 };
 
+use log::{debug, error, warn};
+
 /// Synchronous Exception Handler
 ///
 /// Source is a lower Exception level, where the implemented level
@@ -15,22 +16,23 @@ use crate::{
 unsafe extern "C" fn rust_synchronous_interrupt_imm_lower_aarch64(frame: &mut TrapFrame) -> usize {
     mask_all();
     let esr: EsrElX = EsrElX::from(read_esr_el1());
+    debug!("Synchronous interrupt from lower EL triggered");
+    log_sync_exception();
     match esr.ec {
         0b100100 => {
-            log_sync_exception();
+            warn!("Cause: Data Abort from a lower Exception level");
-            println!("Cause: Data Abort from a lower Exception level");
         }
         0b010101 => {
-            println!("Cause: SVC instruction execution in AArch64");
+            debug!("Cause: SVC instruction execution in AArch64");
             return handle_svc(frame);
         }
         _ => {
-            println!("Unknown Error Code: {:b}", esr.ec);
+            error!("Synchronous interrupt: Unknown Error Code: {:b}", esr.ec);
         }
     }
-    println!("Returning to kernel main...");
 
-    set_return_to_kernel_main();
+    warn!("UnhandledException -> Returning to kernel...");
+    set_return_to_kernel_loop();
     0
 }
 
@@ -46,11 +48,11 @@ fn handle_svc(frame: &mut TrapFrame) -> usize {
 
 fn log_sync_exception() {
     let source_el = read_exception_source_el() >> 2;
-    println!("--------Sync Exception in EL{}--------", source_el);
+    debug!("--------Sync Exception in EL{}--------", source_el);
-    println!("Exception escalated to EL {}", get_current_el());
+    debug!("Exception escalated to EL {}", get_current_el());
-    println!("Current EL: {}", get_current_el());
+    debug!("Current EL: {}", get_current_el());
     let esr: EsrElX = EsrElX::from(read_esr_el1());
-    println!("{:?}", esr);
+    debug!("{:?}", esr);
-    println!("Return address: {:#x}", read_elr_el1());
+    debug!("Return address: {:#x}", read_elr_el1());
-    println!("-------------------------------------");
+    debug!("-------------------------------------");
 }

src/lib.rs

@@ -3,12 +3,13 @@
 
 extern crate alloc;
 
-use alloc::boxed::Box;
 use core::{
     arch::asm,
     panic::PanicInfo,
     ptr::{read_volatile, write_volatile},
 };
+use log::LevelFilter;
+use log::{Level, Metadata, Record};
 
 use heap::Heap;
 
@@ -18,10 +19,11 @@ use crate::{
         WRITABLE,
     },
     interrupt_handlers::irq::initialize_interrupt_handler,
-    logger::DefaultLogger,
     pi3::timer::sleep_s,
+    terminal::{flush_terminal, init_terminal},
 };
 
+static LOGGER: UartLogger = UartLogger;
 static PERIPHERAL_BASE: usize = 0x3F00_0000;
 
 unsafe extern "C" {
@@ -31,7 +33,7 @@ unsafe extern "C" {
 #[global_allocator]
 pub static mut GLOBAL_ALLOCATOR: Heap = Heap::empty();
 
-pub unsafe fn init_kernel_heap() {
+pub unsafe fn initialize_kernel_heap() {
     let start = core::ptr::addr_of_mut!(__kernel_end) as usize | KERNEL_VIRTUAL_MEM_SPACE;
     let size = LEVEL2_BLOCK_SIZE * 2;
 
@@ -54,9 +56,9 @@ pub mod aarch64;
 pub mod configuration;
 pub mod framebuffer;
 pub mod interrupt_handlers;
-pub mod logger;
 
 pub mod pi3;
+pub mod terminal;
 
 #[inline(always)]
 pub unsafe fn read_address(address: u32) -> u32 {
@@ -80,14 +82,33 @@ pub fn get_current_el() -> u64 {
     el >> 2
 }
 
-static mut KERNEL_INITIALIZED: bool = false;
-
 pub fn initialize_kernel() {
-    if unsafe { KERNEL_INITIALIZED } {
+    unsafe { initialize_kernel_heap() };
-        return;
-    }
-    unsafe { init_kernel_heap() };
-    logger::set_logger(Box::new(DefaultLogger));
     initialize_interrupt_handler();
-    unsafe { KERNEL_INITIALIZED = true };
+    init_terminal();
+}
+
+struct UartLogger;
+
+impl log::Log for UartLogger {
+    fn enabled(&self, metadata: &Metadata) -> bool {
+        metadata.level() <= Level::Debug
+    }
+
+    fn log(&self, record: &Record) {
+        if self.enabled(record.metadata()) {
+            println!("{} - {}", record.level(), record.args());
+            if record.level() <= Level::Info {
+                flush_terminal();
+            }
+        }
+    }
+
+    fn flush(&self) {}
+}
+
+pub fn init_logger() {
+    log::set_logger(&LOGGER)
+        .map(|()| log::set_max_level(LevelFilter::Debug))
+        .unwrap();
 }

src/logger.rs

@@ -1,45 +0,0 @@
-use core::fmt::Write;
-
-use alloc::{boxed::Box, fmt};
-
-use crate::peripherals::uart;
-
-static mut LOGGER: Option<Box<dyn Logger>> = None;
-
-pub trait Logger: Write + Sync {
-    fn flush(&mut self);
-}
-
-pub struct DefaultLogger;
-
-impl Logger for DefaultLogger {
-    fn flush(&mut self) {}
-}
-
-impl Write for DefaultLogger {
-    fn write_str(&mut self, s: &str) -> core::fmt::Result {
-        uart::Uart.write_str(s)
-    }
-}
-
-#[macro_export]
-macro_rules! log {
-    () => {};
-    ($($arg:tt)*) => {
-        $crate::logger::log(format_args!($($arg)*))
-    };
-}
-
-pub fn log(args: fmt::Arguments) {
-    if let Some(logger) = unsafe { &mut *core::ptr::addr_of_mut!(LOGGER) } {
-        logger.write_str("\n").unwrap();
-        logger.write_fmt(args).unwrap();
-        logger.flush();
-    }
-}
-
-pub fn set_logger(logger: Box<dyn Logger>) {
-    unsafe {
-        LOGGER = Some(logger);
-    }
-}

src/main.rs

@@ -6,6 +6,7 @@ use core::{
     arch::{asm, global_asm},
     ptr::write_volatile,
 };
+use log::{debug, info};
 
 extern crate alloc;
 
@@ -14,7 +15,7 @@ use nova::{
     aarch64::registers::{daif, read_id_aa64mmfr0_el1},
     configuration::memory_mapping::initialize_mmu_translation_tables,
     framebuffer::{FrameBuffer, BLUE, GREEN, RED},
-    get_current_el,
+    get_current_el, init_logger,
     interrupt_handlers::irq::{enable_irq_source, IRQSource},
     peripherals::{
         gpio::{
@@ -23,7 +24,7 @@ use nova::{
         },
         uart::uart_init,
     },
-    println,
+    print, println,
 };
 
 global_asm!(include_str!("vector.S"));
@@ -33,7 +34,6 @@ static mut FRAMEBUFFER: Option<FrameBuffer> = None;
 
 extern "C" {
     fn el2_to_el1();
-    fn el1_to_el0();
     fn configure_mmu_el1();
     static mut __bss_start: u32;
     static mut __bss_end: u32;
@@ -60,16 +60,18 @@ pub extern "C" fn main() -> ! {
 
     // Set ACT Led to Outout
     let _ = set_gpio_function(21, GPIOFunction::Output);
+    init_logger();
 
-    println!("Hello World!");
+    info!("Hello World!");
-    println!("Exception level: {}", get_current_el());
+    info!("Current exception level: {}", get_current_el());
 
+    info!("initializing MMU...");
     initialize_mmu_translation_tables();
     unsafe { configure_mmu_el1() };
-    println!("MMU initialized...");
+    info!("MMU configured!");
 
-    println!("Register: AA64MMFR0_EL1: {:064b}", read_id_aa64mmfr0_el1());
+    debug!("Register: AA64MMFR0_EL1: {:064b}", read_id_aa64mmfr0_el1());
-    println!("Moving El2->EL1");
+    info!("Moving El2->EL1");
     unsafe { FRAMEBUFFER = Some(FrameBuffer::default()) };
 
     unsafe {
@@ -89,28 +91,32 @@ unsafe fn zero_bss() {
 }
 
 #[no_mangle]
-pub extern "C" fn kernel_main() -> ! {
+pub extern "C" fn kernel_main() {
-    println!("Kernel Start...");
     nova::initialize_kernel();
+    info!("Kernel Initialized...");
+    info!("Current exception Level: {}", get_current_el());
+
     let mut test_vector = Vec::new();
     for i in 0..20 {
         test_vector.push(i);
     }
-    println!("heap allocation test: {:?}", test_vector);
+    debug!("heap allocation test: {:?}", test_vector);
 
-    println!("Exception Level: {}", get_current_el());
+    enable_irq_source(IRQSource::UartInt);
+
+    kernel_loop();
+}
+
+#[no_mangle]
+pub extern "C" fn kernel_loop() {
     daif::unmask_all();
 
-    unsafe {
-        el1_to_el0();
-    };
-
     #[allow(clippy::empty_loop)]
     loop {}
 }
 
 #[no_mangle]
-pub extern "C" fn el0() -> ! {
+pub extern "C" fn el0(input: usize) {
     println!("Jumped into EL0");
 
     // Set GPIO 26 to Input
@@ -119,8 +125,6 @@ pub extern "C" fn el0() -> ! {
     gpio_pull_up(26);
     set_falling_edge_detect(26, true);
 
-    enable_irq_source(IRQSource::UartInt);
-
     if let Some(fb) = unsafe { FRAMEBUFFER.as_mut() } {
         for i in 0..1080 {
             fb.draw_pixel(50, i, BLUE);
@@ -134,12 +138,27 @@ pub extern "C" fn el0() -> ! {
         fb.draw_function(cos, 0, 101, RED);
     }
 
-    loop {
+    let _temp = syscall(67);
-        let temp = syscall(67);
-        println!("{} °C", temp / 1000);
 
-        blink_gpio(SpecificGpio::OnboardLed as u8, 500);
+    println!("Calculting prime to: {}", input);
+
+    for i in 3..input {
+        let mut is_prime = true;
+        for j in 3..i {
+            if i == j {
+                continue;
+            }
+            if i % j == 0 {
+                is_prime = false;
+            }
+        }
+        if is_prime {
+            print!("{} ", i);
+        }
     }
+    println!("");
+
+    blink_gpio(SpecificGpio::OnboardLed as u8, 500);
 }
 
 fn cos(x: u32) -> f64 {

src/terminal.rs

@@ -1,53 +1,92 @@
-use core::fmt::Write;
+use core::arch::asm;
 
 use alloc::string::String;
-use nova::{
+
-    interrupt_handlers::register_interrupt_handler, logger::Logger,
+use crate::{
-    peripherals::uart::read_uart_data, print, println,
+    interrupt_handlers::irq::{register_interrupt_handler, IRQSource},
+    peripherals::uart::read_uart_data,
+    pi3::mailbox::read_soc_temp,
+    print, println,
 };
 
+pub static mut TERMINAL: Option<Terminal> = None;
+
 pub struct Terminal {
-    buffer: String,
     input: String,
 }
 
+extern "C" {
+    fn el1_to_el0();
+}
+
+impl Default for Terminal {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Terminal {
     pub fn new() -> Self {
         Self {
-            buffer: String::new(),
             input: String::new(),
         }
     }
 
     fn flush(&mut self) {
-        println!("{}", self.buffer);
+        print!("\n> {}", self.input);
-        print!("> {}", self.input);
+    }
-        self.buffer.clear();
+
+    fn exec(&mut self) {
+        print!("\n");
+        let val = self.input.clone();
+        self.input.clear();
+
+        match val.as_str() {
+            "temp" => {
+                println!("{}", read_soc_temp([0]).unwrap()[1]);
+            }
+            "el0" => unsafe {
+                let i = 69;
+                asm!("", in("x0") i);
+                el1_to_el0();
+            },
+            _ => {
+                println!("Unknown command: \"{}\"", self.input);
+            }
+        }
+        self.input.clear();
     }
 }
 
-impl Write for Terminal {
+pub fn init_terminal() {
-    fn write_str(&mut self, s: &str) -> core::fmt::Result {
+    unsafe { TERMINAL = Some(Terminal::new()) };
-        self.buffer.push_str(s);
+    register_terminal_interrupt_handler();
-        Ok(())
-    }
-}
-
-impl Logger for Terminal {
-    fn flush(&mut self) {
-        println!("{}", self.buffer);
-        print!("> {}", self.input);
-        self.buffer.clear();
-    }
 }
 
 fn terminal_uart_rx_interrupt_handler() {
-    print!("{}", read_uart_data());
+    let input = read_uart_data();
+    #[allow(static_mut_refs)]
+    if let Some(term) = unsafe { TERMINAL.as_mut() } {
+        match input {
+            '\r' => {
+                term.exec();
+                term.flush();
+            }
+            _ => {
+                term.input.push(input);
+                print!("{}", input);
+            }
+        }
+    }
 }
 
-pub fn register_terminal_interrupt_handler() {
+pub fn flush_terminal() {
-    register_interrupt_handler(
+    #[allow(static_mut_refs)]
-        nova::interrupt_handlers::IRQSource::UartInt,
+    if let Some(term) = unsafe { TERMINAL.as_mut() } {
-        terminal_uart_rx_interrupt_handler,
+        term.flush();
-    );
+    }
+}
+
+fn register_terminal_interrupt_handler() {
+    register_interrupt_handler(IRQSource::UartInt, terminal_uart_rx_interrupt_handler);
 }

workspace/nova_error/src/lib.rs

@@ -11,4 +11,5 @@ pub enum NovaError {
     Misalignment,
     InvalidGranularity,
     Paging,
+    OutOfMeomory,
 }