exosphere: properly implement reboot-to-payload

exosphere/rebootstub/src/start.s

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2018 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+.section .text.start
+.align 4
+.global _start
+_start:
+    b crt0
+
+.global crt0
+.type crt0, %function
+crt0:
+    @ clear all registers
+    ldr r0, =0x52425430 @ RBT0
+    mov r1, #0x0
+    mov r2, #0x0
+    mov r3, #0x0
+    mov r4, #0x0
+    mov r5, #0x0
+    mov r6, #0x0
+    mov r7, #0x0
+    mov r8, #0x0
+    mov r9, #0x0
+    mov r10, #0x0
+    mov r11, #0x0
+    mov r12, #0x0
+    mov lr, #0x0
+    ldr sp, =0x40010000
+    ldr pc, =0x40010000
+    
+
+