demo: initial commit

1 files changed, 57 insertions, 0 deletions

diff --git a/demo/start.S b/demo/start.S
new file mode 100644
index 0000000..6e5e457
--- /dev/null
+++ b/demo/start.S
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+.section .interrupt_vector
+
+__reset:
+	b _start
+
+__undefined:
+	b undefined
+
+__swi:
+	b swi
+
+__prefetch_abort:
+	b prefetch_abort
+
+__data_abort:
+	b data_abort
+
+__reserved:
+	b .
+
+__irq:
+	b irq
+
+__fiq:
+	b .
+
+.text
+
+.global _start
+_start:
+	ldr r0, =_boot_num
+	ldr r1, [r0]
+	add r2, r1, #1
+	str r2, [r0]
+	ldr r2, =__cpus
+	lsl r3, r1, #2
+	ldr ip, [r2, r3]
+	str r1, [ip]
+	ldr r2, =_stack_shift
+	lsl r1, r1, r2
+	ldr sp, =_stack_begin
+	add sp, sp, r1
+	mov lr, #0
+	bl  reset
+	b   .
+
+_boot_num:
+	.word 0
+
+irq:
+	subs pc, lr, #4
+
+.weak undefined, swi, data_abort, prefetch_abort, irq
+.set swi, __swi
+.set undefined, __undefined
+.set data_abort, __data_abort
+.set prefetch_abort, __prefetch_abort