First Try

.github/workflows/rust.yml

@@ -21,7 +21,7 @@ jobs:
       - name: Run format check
         run: cargo fmt --check
       - name: Run lint
-        run: cargo clippy
+        run: cargo clippy -- -D warnings
 
   build:
     runs-on: ubuntu-latest

src/framebuffer.rs

@@ -0,0 +1,109 @@
+use crate::{
+    mailbox::{read_mailbox, write_mailbox},
+    peripherals::uart::{print, print_u32},
+};
+
+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;
+
+pub fn init_fb() {
+    let mut mailbox = [0; 32];
+    mailbox[0] = 32 * 4;
+    mailbox[1] = 0;
+
+    mailbox[2] = SET_PHYSICAL_DISPLAY_WH;
+    mailbox[3] = 8;
+    mailbox[4] = 8;
+    mailbox[5] = 1920;
+    mailbox[6] = 1200;
+
+    mailbox[7] = SET_VIRTUAL_DISPLAY_WH;
+    mailbox[8] = 8;
+    mailbox[9] = 8;
+    mailbox[10] = 1920;
+    mailbox[11] = 1200;
+
+    mailbox[12] = SET_PIXEL_DEPTH;
+    mailbox[13] = 4;
+    mailbox[14] = 4;
+    mailbox[15] = 32; // 32 bit per pixel
+
+    mailbox[16] = SET_PIXEL_ORDER;
+    mailbox[17] = 4;
+    mailbox[18] = 4;
+    mailbox[19] = 0x1; // RGB
+
+    mailbox[20] = SET_FB_OFFSET;
+    mailbox[21] = 8;
+    mailbox[22] = 8;
+    mailbox[24] = 0; // X in pixels
+    mailbox[25] = 0; // Y in pixels
+
+    mailbox[26] = ALLOCATE_BUFFER;
+    mailbox[27] = 8;
+    mailbox[28] = 4;
+    mailbox[29] = 4096; // Alignment
+    mailbox[30] = 0;
+
+    mailbox[31] = 0; // End tag
+
+    // TODO: validate responses
+
+    let addr = core::ptr::addr_of!(mailbox[0]) as u32;
+
+    write_mailbox(8, addr);
+
+    let _ = read_mailbox(8);
+    if mailbox[1] == 0 {
+        print("Failed\r\n");
+    }
+
+    print_u32(mailbox[29]);
+
+    mailbox[29] = (mailbox[29] & 0x00FF_FFFF) | 0x3F00_0000;
+
+    let mut fb: *mut u32 = mailbox[29] as *mut u32;
+
+    fb = unsafe { fb.add(1920 * 500 + 500) };
+
+    for x in 0..500 {
+        for y in 0..10 {
+            unsafe {
+                *fb = 0xFFFFBB00;
+                fb = fb.add(1);
+            };
+        }
+    }
+}
+
+pub fn print_display_resolution() {
+    let mut mailbox = [0; 8];
+    mailbox[0] = 8 * 4;
+    mailbox[1] = 0;
+    mailbox[2] = GET_PHYSICAL_DISPLAY_WH;
+    mailbox[3] = 8;
+    mailbox[4] = 0;
+    mailbox[5] = 0;
+    mailbox[6] = 0;
+    mailbox[7] = 0;
+
+    let addr = core::ptr::addr_of!(mailbox[0]) as u32;
+
+    write_mailbox(8, addr);
+
+    let _ = read_mailbox(8);
+    if mailbox[1] == 0 {
+        print("Failed\r\n");
+    }
+
+    print("Width x Height: ");
+    print_u32(mailbox[5]);
+    print(" x ");
+    print_u32(mailbox[6]);
+    print("\r\n");
+}

src/irq_interrupt.rs

@@ -9,7 +9,7 @@ use crate::{
         gpio::{blink_gpio, SpecificGpio},
         uart::print,
     },
-    timer::{sleep_ms, sleep_s},
+    timer::sleep_s,
 };
 
 const INTERRUPT_BASE: u32 = 0x3F00_B000;

src/lib.rs

@@ -5,6 +5,7 @@ use core::ptr::{read_volatile, write_volatile};
 pub mod peripherals;
 
 pub mod configuration;
+pub mod framebuffer;
 pub mod irq_interrupt;
 pub mod mailbox;
 pub mod timer;

src/mailbox.rs

@@ -34,7 +34,7 @@ pub fn write_mailbox(channel: u32, data: u32) {
 }
 
 pub fn read_soc_temp() -> u32 {
-    let mut mailbox = [0; 36];
+    let mut mailbox = [0; 8];
     mailbox[0] = 8 * 4; // Total size in bytes
     mailbox[1] = 0; // Request
     mailbox[2] = 0x00030006; // Tag

src/main.rs

@@ -9,6 +9,7 @@ use core::{
 };
 
 use nova::{
+    framebuffer::{init_fb, print_display_resolution},
     irq_interrupt::enable_irq_source,
     mailbox::read_soc_temp,
     peripherals::{
@@ -92,9 +93,13 @@ pub extern "C" fn kernel_main() -> ! {
     gpio_pull_up(26);
     set_falling_edge_detect(26, true);
 
+    print_display_resolution();
+    init_fb();
+
     loop {
         let temp = read_soc_temp();
         print_u32(temp);
+        print("\r\n");
 
         blink_gpio(SpecificGpio::OnboardLed as u8, 500);
     }

src/peripherals/uart.rs

@@ -57,7 +57,6 @@ pub fn print_u32(mut val: u32) {
         let s = str::from_utf8(&data).unwrap();
         print(s);
     }
-    print("\r\n");
 }
 
 /// Initialize UART peripheral