annotate target-utils/env/crt0.S @ 517:809829dbc58a

new flash support documented
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 01 Jun 2019 06:46:46 +0000
parents e7502631a0f9
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
0
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 #include "halt.h"
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 .text
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4 .code 32
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 .global _entry
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 _entry:
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7 ldr sp, =stack_bottom
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 @ zero bss
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9 ldr r0, =__bss_start
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 ldr r2, =__bss_end
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 sub r1, r2, r0
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 bl bzero
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 @ C code entry
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 bl main
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 mov r0, #HALTCODE_MAINEXITED
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 .global _exit
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 _exit: nop
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 1: nop
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 b 1b