Remove unused import

.gitignore

@@ -2,3 +2,4 @@
 kernel8.img
 .env
 sd.img
+settings.json

.vscode/settings.json

@@ -1,6 +0,0 @@
-{
-  "lldb.displayFormat": "auto",
-  "lldb.showDisassembly": "always",
-  "lldb.dereferencePointers": true,
-  "lldb.consoleMode": "commands"
-}

link.ld

@@ -27,10 +27,9 @@ SECTIONS {
         KEEP(*(.vector_table))
     }
 
-    .stack 0x8008000 : ALIGN(16)
+    .stack 0x8018000 : ALIGN(16)
     {
     __stack_start = .;
-    .+=0x10000;
     __stack_end = .;
     }
 

src/configuration.rs

@@ -0,0 +1,15 @@
+static SCTLR_EL1_MMU_DISABLED: u64 = 0 << 0; //M
+static SCTLR_EL1_DATA_CACHE_DISABLED: u64 = 0 << 2; //C
+static SCTLR_EL1_INSTRUCTION_CACHE_DISABLED: u64 = 0 << 12; //I
+static SCTLR_EL1_LITTLE_ENDIAN_EL0: u64 = 0 << 24; //E0E
+static SCTLR_EL1_LITTLE_ENDIAN_EL1: u64 = 0 << 25; //EE
+
+static SCTLR_EL1_RES: u64 = (0 << 6) | (1 << 11) | (0 << 17) | (1 << 20) | (1 << 22); //Res0 & Res1
+
+#[no_mangle]
+pub static SCTLR_EL1_CONF: u64 = SCTLR_EL1_MMU_DISABLED
+    | SCTLR_EL1_DATA_CACHE_DISABLED
+    | SCTLR_EL1_INSTRUCTION_CACHE_DISABLED
+    | SCTLR_EL1_LITTLE_ENDIAN_EL0
+    | SCTLR_EL1_LITTLE_ENDIAN_EL1
+    | SCTLR_EL1_RES;

src/irq_interrupt.rs

@@ -5,7 +5,11 @@ use core::{
 
 use crate::{
     mmio_read, mmio_write,
-    peripherals::{gpio::blink_gpio, uart::print},
+    peripherals::{
+        gpio::{blink_gpio, SpecificGpio},
+        uart::print,
+    },
+    timer::{sleep_ms, sleep_s},
 };
 
 const INTERRUPT_BASE: u32 = 0x3F00_B000;
@@ -41,10 +45,34 @@ unsafe extern "C" fn irq_handler() {
 #[no_mangle]
 unsafe extern "C" fn synchronous_interrupt() {
     loop {
-        let el: u64;
-        asm!("mrs x5, FAR_EL1");
-        blink_gpio(29, 100);
         print("Sync Exception \r\n");
+        blink_gpio(SpecificGpio::OnboardLed as u8, 100);
+        esr_uart_dump();
+        sleep_s(200);
+    }
+}
+
+fn esr_uart_dump() {
+    let esr: u32;
+    unsafe {
+        asm!(
+            "mrs {esr}, ESR_EL1",
+            esr = out(reg) esr
+        );
+    }
+    for i in (0..32).rev() {
+        if ((esr >> i) & 1) == 0 {
+            print("0");
+        } else {
+            print("1");
+        }
+        if i % 4 == 0 && i > 0 {
+            print("_");
+        }
+
+        if i == 26 || i == 25 || i == 0 {
+            print("\n\r");
+        }
     }
 }
 

src/lib.rs

@@ -4,6 +4,7 @@ use core::ptr::{read_volatile, write_volatile};
 
 pub mod peripherals;
 
+pub mod configuration;
 pub mod irq_interrupt;
 pub mod mailbox;
 pub mod timer;

src/mailbox.rs

@@ -1,9 +1,4 @@
-use core::ptr::read_volatile;
+use crate::{mmio_read, mmio_write, peripherals::uart::print};
-
-use crate::{
-    mmio_read, mmio_write,
-    peripherals::uart::{print, print_u32},
-};
 
 const MBOX_BASE: u32 = 0x3F00_0000 + 0xB880;
 
@@ -18,12 +13,6 @@ const MBOX_WRITE: u32 = MBOX_BASE + 0x20;
 const MAIL_FULL: u32 = 0x80000000;
 const MAIL_EMPTY: u32 = 0x40000000;
 
-#[repr(C, align(16))]
-struct MailboxBuffer([u32; 36]);
-
-#[no_mangle]
-static mut MBOX: MailboxBuffer = MailboxBuffer([0; 36]);
-
 pub fn read_mailbox(channel: u32) -> u32 {
     // Wait until mailbox is not empty
     loop {
@@ -45,30 +34,25 @@ pub fn write_mailbox(channel: u32, data: u32) {
 }
 
 pub fn read_soc_temp() -> u32 {
-    unsafe {
+    let mut mailbox = [0; 36];
-        // MBOX.0[0] = 7 * 4; // Total size in bytes
+    mailbox[0] = 8 * 4; // Total size in bytes
-        // MBOX.0[1] = 0; // Request
+    mailbox[1] = 0; // Request
-        // MBOX.0[2] = 0x00010002; // Tag
+    mailbox[2] = 0x00030006; // Tag
-        // MBOX.0[3] = 4; // Maximum buffer lenb
+    mailbox[3] = 8; // Maximum buffer len
-        // MBOX.0[4] = 0; // Request length
+    mailbox[4] = 4; // Request length
-        // MBOX.0[5] = 0; // Value Buffer
+    mailbox[5] = 0; // Value Buffer
-        // MBOX.0[6] = 0; // End
+    mailbox[6] = 0; // Value Buffer
-        // core::arch::asm!("dsb sy"); // Ensure write reaches RAM
+    mailbox[7] = 0; // End
-        // core::arch::asm!("dmb sy"); // Memory barrier
 
-        print("Reading address\r\n");
+    let addr = core::ptr::addr_of!(mailbox[0]) as u32;
-        //let addr = core::ptr::addr_of!(MBOX.0[0]);
 
-        print("Write address\r\n");
+    write_mailbox(8, addr);
-
-        // write_mailbox(8, addr);
 
     let _ = read_mailbox(8);
 
-        if MBOX.0[1] == 0 {
+    if mailbox[1] == 0 {
         print("Failed\r\n");
     }
-        let raw_temp = MBOX.0[5];
+    let raw_temp = mailbox[6] / 1000;
     raw_temp
 }
-}

src/main.rs

@@ -14,6 +14,7 @@ use nova::{
     peripherals::{
         gpio::{
             blink_gpio, gpio_pull_up, set_falling_edge_detect, set_gpio_function, GPIOFunction,
+            SpecificGpio,
         },
         uart::{print, print_u32, uart_init},
     },
@@ -81,7 +82,6 @@ unsafe fn zero_bss() {
 
 #[no_mangle]
 pub extern "C" fn kernel_main() -> ! {
-    print("AAA\r\n");
     print_current_el_str();
 
     sleep_us(500_000);
@@ -96,7 +96,7 @@ pub extern "C" fn kernel_main() -> ! {
         let temp = read_soc_temp();
         print_u32(temp);
 
-        blink_gpio(29, 500);
+        blink_gpio(SpecificGpio::OnboardLed as u8, 500);
     }
 }
 

src/peripherals/gpio.rs

@@ -13,6 +13,11 @@ const GPPUDCLK_BASE: u32 = 0x3F20_0098;
 const GPREN_BASE: u32 = 0x3F20_004C;
 const GPFEN_BASE: u32 = 0x3F20_0058;
 
+#[repr(u8)]
+pub enum SpecificGpio {
+    OnboardLed = 29,
+}
+
 #[repr(u32)]
 pub enum GPIOFunction {
     Input = 0b000,

src/peripherals/uart.rs

@@ -1,4 +1,4 @@
-use core::{arch::asm, fmt};
+use core::arch::asm;
 
 use crate::{mmio_read, mmio_write};
 
@@ -33,17 +33,24 @@ pub fn print(s: &str) {
 }
 
 pub fn print_u32(mut val: u32) {
+    let mut last_valid = 0;
     let mut values = [0u32; 10];
-    for c in &mut values {
+    for (i, c) in (&mut values).iter_mut().enumerate() {
         if val == 0 {
             break;
         }
 
         *c = val % 10;
         val /= 10;
+        if *c != 0 {
+            last_valid = i;
+        }
     }
 
-    for c in values.iter().rev() {
+    for (i, c) in values.iter().enumerate().rev() {
+        if i > last_valid {
+            continue;
+        }
         let ascii_byte = b'0' + *c as u8;
         let data = [ascii_byte];
 

src/vector.S

@@ -21,7 +21,6 @@ vector_table:
 
 
 .align 4
-.extern main
 .global el2_to_el1
 el2_to_el1:
 
@@ -45,10 +44,15 @@ el2_to_el1:
     msr VBAR_EL1, x0
 
     // Disable MMU
-    mrs x0, sctlr_el1
+    ldr x0, =SCTLR_EL1_CONF
-    bic x0, x0, #1
     msr sctlr_el1, x0
 
+    // SIMD should not be trapped
+    mrs x0, CPACR_EL1
+    mov x1, #(0b11<<20)
+    orr x0,x0, x1
+    msr CPACR_EL1,x0
+
     isb
 
     // Return to EL1