Reduce clutter by using print macros with fmt

src/framebuffer.rs

@@ -4,21 +4,18 @@ mod bitmaps;
 
 use bitmaps::BASIC_LEGACY;
 
-use crate::{
-    mailbox::{read_mailbox, write_mailbox},
-    peripherals::uart::{print, print_u32, print_u32_hex},
-};
+use crate::mailbox::{read_mailbox, write_mailbox};
 #[repr(align(16))]
 struct Mailbox([u32; 36]);
 
-const ALLOCATE_BUFFER: u32 = 0x00040001;
-const GET_PHYSICAL_DISPLAY_WH: u32 = 0x00040003;
-const SET_PHYSICAL_DISPLAY_WH: u32 = 0x00048003;
-const SET_VIRTUAL_DISPLAY_WH: u32 = 0x00048004;
-const SET_PIXEL_DEPTH: u32 = 0x00048005;
-const SET_PIXEL_ORDER: u32 = 0x00048006;
-const SET_FB_OFFSET: u32 = 0x00048009;
-const GET_PITCH: u32 = 0x00040008;
+const ALLOCATE_BUFFER: u32 = 0x0004_0001;
+const GET_PHYSICAL_DISPLAY_WH: u32 = 0x0004_0003;
+const SET_PHYSICAL_DISPLAY_WH: u32 = 0x0004_8003;
+const SET_VIRTUAL_DISPLAY_WH: u32 = 0x0004_8004;
+const SET_PIXEL_DEPTH: u32 = 0x0004_8005;
+const SET_PIXEL_ORDER: u32 = 0x0004_8006;
+const GET_PITCH: u32 = 0x000_40008;
+const SET_FB_OFFSET: u32 = 0x0004_8009;
 
 pub struct FrameBuffer {
     pixel_depth: u32, // Bits per pixel
@@ -89,7 +86,7 @@ impl FrameBuffer {
 
         let _ = read_mailbox(8);
         if mailbox.0[1] == 0 {
-            print("Failed\r\n");
+            println!("Failed");
         }
 
         mailbox.0[28] &= 0x3FFFFFFF;
@@ -263,12 +260,8 @@ pub fn print_display_resolution() {
 
     let _ = read_mailbox(8);
     if mailbox[1] == 0 {
-        print("Failed\r\n");
+        println!("Failed");
     }
 
-    print("Width x Height: ");
-    print_u32(mailbox[5]);
-    print(" x ");
-    print_u32(mailbox[6]);
-    print("\r\n");
+    println!("Width x Height: {}x{}", mailbox[5], mailbox[6]);
 }

src/irq_interrupt.rs

@@ -5,10 +5,8 @@ use core::{
 
 use crate::{
     mmio_read, mmio_write,
-    peripherals::{
-        gpio::{blink_gpio, SpecificGpio},
-        uart::print,
-    },
+    peripherals::gpio::{blink_gpio, SpecificGpio},
+    print,
     timer::sleep_s,
 };
 
@@ -45,7 +43,7 @@ unsafe extern "C" fn irq_handler() {
 #[no_mangle]
 unsafe extern "C" fn synchronous_interrupt() {
     loop {
-        print("Sync Exception \r\n");
+        println!("Sync Exception");
         blink_gpio(SpecificGpio::OnboardLed as u8, 100);
         esr_uart_dump();
         sleep_s(200);
@@ -62,28 +60,28 @@ fn esr_uart_dump() {
     }
     for i in (0..32).rev() {
         if ((esr >> i) & 1) == 0 {
-            print("0");
+            print!("0");
         } else {
-            print("1");
+            print!("1");
         }
         if i % 4 == 0 && i > 0 {
-            print("_");
+            print!("_");
         }
 
         if i == 26 || i == 25 || i == 0 {
-            print("\n\r");
+            print!("\n\r");
         }
     }
 }
 
 fn handle_gpio_interrupt() {
-    print("Interrupt\r\n");
+    println!("Interrupt");
     for i in 0..=53u32 {
         let val = read_gpio_event_detect_status(i);
 
         if val {
             match i {
-                26 => print("Button Pressed"),
+                26 => print!("Button Pressed"),
                 _ => {}
             }
             // Reset GPIO Interrupt handler by writing a 1

src/lib.rs

@@ -2,6 +2,23 @@
 
 use core::ptr::{read_volatile, write_volatile};
 
+#[macro_export]
+macro_rules! print {
+    () => {};
+    ($($arg:tt)*) => {
+        $crate::peripherals::uart::_print(format_args!($($arg)*))
+    };
+}
+
+#[macro_export]
+macro_rules! println {
+    () => {};
+    ($($arg:tt)*) => {
+        print!($($arg)*);
+        print!("\r\n");
+    };
+}
+
 pub mod peripherals;
 
 pub mod configuration;

src/mailbox.rs

@@ -1,4 +1,4 @@
-use crate::{mmio_read, mmio_write, peripherals::uart::print};
+use crate::{mmio_read, mmio_write, print};
 
 const MBOX_BASE: u32 = 0x3F00_0000 + 0xB880;
 
@@ -51,7 +51,7 @@ pub fn read_soc_temp() -> u32 {
     let _ = read_mailbox(8);
 
     if mailbox[1] == 0 {
-        print("Failed\r\n");
+        println!("Failed");
     }
     let raw_temp = mailbox[6] / 1000;
     raw_temp

src/main.rs

@@ -18,8 +18,9 @@ use nova::{
             blink_gpio, gpio_pull_up, set_falling_edge_detect, set_gpio_function, GPIOFunction,
             SpecificGpio,
         },
-        uart::{print, print_u32, uart_init},
+        uart::uart_init,
     },
+    print, println,
     timer::{delay_nops, sleep_us},
 };
 
@@ -34,7 +35,7 @@ extern "C" {
 #[panic_handler]
 fn panic(_panic: &PanicInfo) -> ! {
     loop {
-        print("Panic\r\n");
+        println!("Panic");
     }
 }
 
@@ -64,7 +65,7 @@ pub extern "C" fn main() -> ! {
 
     // Delay so clock speed can stabilize
     delay_nops(50000);
-    print("Hello World!\r\n");
+    println!("Hello World!");
 
     unsafe {
         asm!("mrs x0, SCTLR_EL1");
@@ -123,8 +124,7 @@ pub extern "C" fn kernel_main() -> ! {
 
     loop {
         let temp = read_soc_temp();
-        print_u32(temp);
-        print("\r\n");
+        println!("{} °C", temp);
 
         blink_gpio(SpecificGpio::OnboardLed as u8, 500);
     }
@@ -163,6 +163,5 @@ fn print_current_el_str() {
         _ => "Unknown EL",
     };
 
-    print(el_str);
-    print("\r\n");
+    println!("{}", el_str);
 }

src/peripherals/mod.rs

@@ -1,2 +1,3 @@
 pub mod gpio;
+#[macro_use]
 pub mod uart;

src/peripherals/uart.rs

@@ -1,4 +1,7 @@
-use core::arch::asm;
+use core::{
+    arch::asm,
+    fmt::{self, Write},
+};
 
 use crate::{mmio_read, mmio_write};
 
@@ -20,76 +23,28 @@ const UART0_CR_TXE: u32 = 1 << 8;
 const UART0_LCRH: u32 = 0x3F20_102c;
 const UART0_LCRH_FEN: u32 = 1 << 4;
 
-/// Print `s` over UART
-pub fn print(s: &str) {
-    for byte in s.bytes() {
-        while (mmio_read(UART0_FR) & UART0_FR_TXFF) != 0 {
-            unsafe { asm!("nop") }
-        }
-        mmio_write(UART0_DR, byte as u32);
-    }
-    // wait till uart is not busy anymore
-    while ((mmio_read(UART0_FR) >> 3) & 0b1) != 0 {}
-}
+pub struct Uart;
 
-pub fn print_u32(mut val: u32) {
-    let mut last_valid = 0;
-    let mut values = [0u32; 10];
-    for (i, c) in (&mut values).iter_mut().enumerate() {
-        if val == 0 {
-            break;
+impl Write for Uart {
+    fn write_str(&mut self, s: &str) -> core::fmt::Result {
+        for byte in s.bytes() {
+            while (mmio_read(UART0_FR) & UART0_FR_TXFF) != 0 {
+                unsafe { asm!("nop") }
+            }
+            mmio_write(UART0_DR, byte as u32);
         }
-
-        *c = val % 10;
-        val /= 10;
-        if *c != 0 {
-            last_valid = i;
-        }
-    }
-
-    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];
-
-        let s = str::from_utf8(&data).unwrap();
-        print(s);
+        // wait till uart is not busy anymore
+        while ((mmio_read(UART0_FR) >> 3) & 0b1) != 0 {}
+        Ok(())
     }
 }
 
-pub fn print_u32_hex(mut val: u32) {
-    let mut last_valid = 0;
-    let mut values = [0u32; 8];
-    for (i, c) in (&mut values).iter_mut().enumerate() {
-        if val == 0 {
-            break;
-        }
+pub fn _print(args: fmt::Arguments) {
+    let _ = Uart.write_fmt(args);
+}
 
-        *c = val % 16;
-        val /= 16;
-        if *c != 0 {
-            last_valid = i;
-        }
-    }
-
-    for (i, c) in values.iter().enumerate().rev() {
-        if i > last_valid {
-            continue;
-        }
-
-        let ascii_byte = if *c < 10 {
-            b'0' + *c as u8
-        } else {
-            b'A' - 10 + *c as u8
-        };
-
-        let data = [ascii_byte];
-
-        let s = str::from_utf8(&data).unwrap();
-        print(s);
-    }
+pub fn _print_str(st: &str) {
+    let _ = Uart.write_str(st);
 }
 
 /// Initialize UART peripheral