feat: Enable EL0 basic mailbox access via SVCs

2026-04-17 04:32:27 +00:00 · 2026-03-21 18:21:32 +01:00
parent aed9c39283
commit 6c36d88b48
8 changed files with 224 additions and 181 deletions
--- a/src/configuration/memory_mapping.rs
+++ b/src/configuration/memory_mapping.rs
@@ -0,0 +1,113 @@
+use crate::{
+    aarch64::mmu::{
+        alloc_block_l2_explicit, allocate_memory, map_l2_block, map_page,
+        physical_mapping::reserve_page, reserve_range, PhysAddr, PhysSource, VirtAddr, DEVICE_MEM,
+        EL0_ACCESSIBLE, GRANULARITY, KERNEL_VIRTUAL_MEM_SPACE, LEVEL1_BLOCK_SIZE,
+        LEVEL2_BLOCK_SIZE, NORMAL_MEM, PXN, READ_ONLY, STACK_START_ADDR, TRANSLATIONTABLE_TTBR0,
+        UXN, WRITABLE,
+    },
+    PERIPHERAL_BASE,
+};
+
+#[no_mangle]
+static EL1_STACK_TOP: usize = STACK_START_ADDR | KERNEL_VIRTUAL_MEM_SPACE;
+const EL1_STACK_SIZE: usize = LEVEL2_BLOCK_SIZE * 2;
+#[no_mangle]
+static EL0_STACK_TOP: usize = STACK_START_ADDR;
+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;
+
+extern "C" {
+    static __text_end: u64;
+    static __share_end: u64;
+    static __kernel_end: u64;
+}
+
+pub fn initialize_mmu_translation_tables() {
+    let text_end = unsafe { &__text_end } as *const _ as usize;
+    let shared_segment_end = unsafe { &__share_end } as *const _ as usize;
+    let kernel_end = unsafe { &__kernel_end } as *const _ as usize;
+
+    reserve_range(0x0, kernel_end).unwrap();
+
+    for addr in (0..text_end).step_by(GRANULARITY) {
+        map_page(
+            addr,
+            addr,
+            core::ptr::addr_of_mut!(TRANSLATIONTABLE_TTBR0),
+            EL0_ACCESSIBLE | READ_ONLY | NORMAL_MEM,
+        )
+        .unwrap();
+    }
+
+    for addr in (text_end..shared_segment_end).step_by(GRANULARITY) {
+        map_page(
+            addr,
+            addr,
+            core::ptr::addr_of_mut!(TRANSLATIONTABLE_TTBR0),
+            EL0_ACCESSIBLE | WRITABLE | NORMAL_MEM,
+        )
+        .unwrap();
+    }
+
+    for addr in (shared_segment_end..kernel_end).step_by(LEVEL2_BLOCK_SIZE) {
+        map_l2_block(
+            addr,
+            addr,
+            core::ptr::addr_of_mut!(TRANSLATIONTABLE_TTBR0),
+            WRITABLE | UXN | NORMAL_MEM,
+        )
+        .unwrap();
+    }
+
+    for addr in (PERIPHERAL_BASE..LEVEL1_BLOCK_SIZE).step_by(LEVEL2_BLOCK_SIZE) {
+        alloc_block_l2_explicit(
+            addr,
+            addr,
+            core::ptr::addr_of_mut!(TRANSLATIONTABLE_TTBR0),
+            EL0_ACCESSIBLE | WRITABLE | UXN | PXN | DEVICE_MEM,
+        )
+        .unwrap();
+    }
+
+    // Frame Buffer memory range
+    allocate_memory(
+        0x3c100000,
+        1080 * 1920 * 4,
+        PhysSource::Explicit(0x3c100000),
+        NORMAL_MEM | PXN | UXN | WRITABLE | EL0_ACCESSIBLE,
+    )
+    .unwrap();
+
+    // Allocate EL1 stack
+    allocate_memory(
+        EL1_STACK_TOP - EL1_STACK_SIZE + 0x10,
+        EL1_STACK_SIZE,
+        PhysSource::Any,
+        WRITABLE | NORMAL_MEM,
+    )
+    .unwrap();
+
+    // Allocate EL0 stack
+    allocate_memory(
+        EL0_STACK_TOP - EL0_STACK_SIZE + 0x10,
+        EL0_STACK_SIZE,
+        PhysSource::Any,
+        WRITABLE | EL0_ACCESSIBLE | NORMAL_MEM,
+    )
+    .unwrap();
+
+    {
+        let addr = reserve_page();
+        unsafe { MAILBOX_PHYSICAL_ADDRESS = Some(addr) };
+        allocate_memory(
+            MAILBOX_VIRTUAL_ADDRESS,
+            GRANULARITY,
+            PhysSource::Explicit(addr),
+            WRITABLE | NORMAL_MEM,
+        )
+        .unwrap();
+    }
+}