Extract dma_copy to its own module

agb/src/display/tiled/map.rs

@@ -3,6 +3,7 @@ use core::ops::{Deref, DerefMut};
 
 use crate::bitarray::Bitarray;
 use crate::display::{self, Priority, DISPLAY_CONTROL};
+use crate::dma::dma_copy;
 use crate::fixnum::Vector2D;
 use crate::memory_mapped::MemoryMapped;
 
@@ -190,28 +191,3 @@ fn div_ceil(x: i32, y: i32) -> i32 {
         x / y
     }
 }
-
-const fn dma_source_addr(dma: usize) -> usize {
-    0x0400_00b0 + 0x0c * dma
-}
-
-const fn dma_dest_addr(dma: usize) -> usize {
-    0x0400_00b4 + 0x0c * dma
-}
-
-const fn dma_control_addr(dma: usize) -> usize {
-    0x0400_00b8 + 0x0c * dma
-}
-
-const DMA3_SOURCE_ADDR: MemoryMapped<u32> = unsafe { MemoryMapped::new(dma_source_addr(3)) };
-const DMA3_DEST_ADDR: MemoryMapped<u32> = unsafe { MemoryMapped::new(dma_dest_addr(3)) };
-const DMA3_CONTROL: MemoryMapped<u32> = unsafe { MemoryMapped::new(dma_control_addr(3)) };
-
-unsafe fn dma_copy(src: *const u16, dest: *mut u16, count: usize) {
-    assert!(count < u16::MAX as usize);
-
-    DMA3_SOURCE_ADDR.set(src as u32);
-    DMA3_DEST_ADDR.set(dest as u32);
-
-    DMA3_CONTROL.set(count as u32 | (1 << 31));
-}

agb/src/display/tiled/vram_manager.rs

@@ -3,6 +3,7 @@ use alloc::vec::Vec;
 
 use crate::{
     display::palette16,
+    dma::dma_copy,
     memory_mapped::{MemoryMapped, MemoryMapped1DArray},
 };
 
@@ -291,28 +292,3 @@ impl<'a> VRamManager<'a> {
         }
     }
 }
-
-const fn dma_source_addr(dma: usize) -> usize {
-    0x0400_00b0 + 0x0c * dma
-}
-
-const fn dma_dest_addr(dma: usize) -> usize {
-    0x0400_00b4 + 0x0c * dma
-}
-
-const fn dma_control_addr(dma: usize) -> usize {
-    0x0400_00b8 + 0x0c * dma
-}
-
-const DMA3_SOURCE_ADDR: MemoryMapped<u32> = unsafe { MemoryMapped::new(dma_source_addr(3)) };
-const DMA3_DEST_ADDR: MemoryMapped<u32> = unsafe { MemoryMapped::new(dma_dest_addr(3)) };
-const DMA3_CONTROL: MemoryMapped<u32> = unsafe { MemoryMapped::new(dma_control_addr(3)) };
-
-unsafe fn dma_copy(src: *const u16, dest: *mut u16, count: usize) {
-    assert!(count < u16::MAX as usize);
-
-    DMA3_SOURCE_ADDR.set(src as u32);
-    DMA3_DEST_ADDR.set(dest as u32);
-
-    DMA3_CONTROL.set(count as u32 | (1 << 31));
-}

agb/src/dma.rs

@@ -0,0 +1,26 @@
+use crate::memory_mapped::MemoryMapped;
+
+const fn dma_source_addr(dma: usize) -> usize {
+    0x0400_00b0 + 0x0c * dma
+}
+
+const fn dma_dest_addr(dma: usize) -> usize {
+    0x0400_00b4 + 0x0c * dma
+}
+
+const fn dma_control_addr(dma: usize) -> usize {
+    0x0400_00b8 + 0x0c * dma
+}
+
+const DMA3_SOURCE_ADDR: MemoryMapped<u32> = unsafe { MemoryMapped::new(dma_source_addr(3)) };
+const DMA3_DEST_ADDR: MemoryMapped<u32> = unsafe { MemoryMapped::new(dma_dest_addr(3)) };
+const DMA3_CONTROL: MemoryMapped<u32> = unsafe { MemoryMapped::new(dma_control_addr(3)) };
+
+pub(crate) unsafe fn dma_copy(src: *const u16, dest: *mut u16, count: usize) {
+    assert!(count < u16::MAX as usize);
+
+    DMA3_SOURCE_ADDR.set(src as u32);
+    DMA3_DEST_ADDR.set(dest as u32);
+
+    DMA3_CONTROL.set(count as u32 | (1 << 31));
+}

agb/src/lib.rs

@@ -142,6 +142,7 @@ mod arena;
 mod bitarray;
 /// Implements everything relating to things that are displayed on screen.
 pub mod display;
+mod dma;
 /// Button inputs to the system.
 pub mod input;
 #[doc(hidden)] // hide for now as the implementation in here is unsound