4 files changed, 115 insertions, 0 deletions
diff --git a/src/_arch/arm/asm.rs b/src/_arch/arm/asm.rs
new file mode 100644
index 0000000..c400f2f
--- /dev/null
+++ b/src/_arch/arm/asm.rs
@@ -0,0 +1,9 @@
+//! Wrapping ARMv7-A Instructions
+
+/// WFE
+/// #[inline(always)]
+pub fn wfe() {
+    unsafe {
+        core::arch::asm!("wfe", options(nomem, nostack))
+    }
+}
diff --git a/src/_arch/arm/cpu.rs b/src/_arch/arm/cpu.rs
new file mode 100644
index 0000000..1ca6fab
--- /dev/null
+++ b/src/_arch/arm/cpu.rs
@@ -0,0 +1,10 @@
+//! Architectural processor code.
+mod asm;
+pub use asm::*;
+
+/// Pause execution
+pub fn wait_forever() -> ! {
+    loop {
+        asm::wfe()
+    }
+}
diff --git a/src/_arch/arm/cpu/boot.rs b/src/_arch/arm/cpu/boot.rs
new file mode 100644
index 0000000..9ea2330
--- /dev/null
+++ b/src/_arch/arm/cpu/boot.rs
@@ -0,0 +1,12 @@
+//! Architectural boot code
+//!  # Boot code for ARM
+//!  crate::cpu::boot::arch_boot
+
+use core::arch::global_asm;
+global_asm!(include_str!("boot.s"));
+
+/// The Rust entry of the `kernel` binary.
+#[no_mangle]
+pub unsafe fn _start_rust() -> ! {
+    crate::kernel_init()
+}
diff --git a/src/_arch/arm/cpu/boot.s b/src/_arch/arm/cpu/boot.s
new file mode 100644
index 0000000..fd2a652
--- /dev/null
+++ b/src/_arch/arm/cpu/boot.s
@@ -0,0 +1,84 @@
+.equ _core_id_mask, 0b11
+.section .text.boot
+
+.global _start
+_start:
+reset:
+	cpsid aif
+	mrc p15, #0, r1, c0, c0, #5
+	and r1, r1, #_core_id_mask
+	cmp r1, #1
+	beq core1run
+	cmp r1, #2
+	beq core2run
+	cmp r1, #3
+	beq core3run
+
+	ldr r0, =vector
+	mcr p15, 0, r0, c12, c0, 0
+	cps #0x12
+	ldr sp, =core0_irq_stack
+	cps #0x11
+	ldr sp, =core0_fiq_stack
+	cps #0x1B
+	ldr sp, =core0_undefined_stack
+	cps #0x17
+	ldr sp, =core0_data_stack
+	cps #0x1f
+	ldr sp, =core0_sys_stack
+	cps #0x13
+	ldr sp, =core0_svc_stack
+
+	ldr r4, =__bss_start
+	ldr r9, =__bss_end
+	mov r5, #0
+	mov r6, #0
+	mov r7, #0
+	mov r8, #0
+	b 2f
+1:
+	stmia r4!, {{r5-r8}}
+2:
+	cmp r4, r9
+	blo 1b
+
+	ldr r3, =_start_rust
+	blx r3
+
+core1run:
+core2run:
+core3run:
+.global io_halt
+undefined:
+io_halt:
+	wfi
+	b io_halt
+
+.align 5
+vector:
+	ldr pc, reset_handler
+	ldr pc, undefined_handler
+	ldr pc, undefined_handler
+	ldr pc, undefined_handler
+	ldr pc, undefined_handler
+	ldr pc, undefined_handler
+	ldr pc, undefined_handler
+	ldr pc, undefined_handler
+
+reset_handler: .word reset
+undefined_handler: .word undefined
+
+.section .bss.sysstacks
+.align 4
+	.space 4096
+core0_undefined_stack:
+	.space 4096
+core0_svc_stack:
+	.space 4096
+core0_data_stack:
+	.space 4096
+core0_irq_stack:
+	.space 4096
+core0_fiq_stack:
+	.space 4096
+core0_sys_stack: