exo: add stub warmboot.bin

exosphere/lp0fw/src/start.s

@@ -0,0 +1,68 @@
+/*
+ * 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
+
+/* Warmboot header. */
+/* Binary size */
+.word __total_size__
+.rept 3
+.word 0x00000000
+.endr
+/* RSA modulus */
+.rept 0x40
+.word 0xFFFFFFFF
+.endr
+/* Padding */
+.rept 4
+.word 0x00000000
+.endr
+/* RSA signature */
+.rept 0x40
+.word 0xFFFFFFFF
+.endr
+/* Padding */
+.rept 4
+.word 0x00000000
+.endr
+/* Relocation meta */
+.word __total_size__
+.word _start
+.word _start
+.word __executable_size__
+
+.global _start
+_start:
+    b crt0
+.rept 0x7C
+    .word  0x00000000 /* Padding */
+.endr
+
+.global _metadata
+_metadata:
+    .ascii "WBT0"     /* Magic number */
+    .word  0x00000000 /* TrustZone relative base. */
+    .word  0x00000000 /* Reserved */
+    .word  0x00000000 /* Reserved */
+
+.global crt0
+.type crt0, %function
+crt0:
+    @ setup to call lp0_entry_main
+    ldr sp, =__stack_top__
+    ldr lr, =reboot
+    ldr r0, =_metadata
+    b lp0_entry_main