annotate src/entry.S @ 94:d876c9a65239 default tip

impl mac os target
author anatofuz <anatofuz@cr.ie.u-ryukyu.ac.jp>
date Wed, 23 Oct 2019 14:31:38 +0900
parents 397e74cbf14e
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
0
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
1 #include "arm.h"
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
2 #include "memlayout.h"
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
3
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
4 .text
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
5 .code 32
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
6
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
7 .global _start
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
8
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
9 _start:
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
10 # clear the entry bss section, the svc stack, and kernel page table
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
11 LDR r1, =edata_entry
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
12 LDR r2, =end_entry
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
13 MOV r3, #0x00
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
14
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
15 1:
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
16 CMP r1, r2
22
397e74cbf14e fix warnings
mir3636
parents: 19
diff changeset
17 STMLTIA r1!, {r3}
397e74cbf14e fix warnings
mir3636
parents: 19
diff changeset
18 # STMIALT r1!, {r3}
0
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
19 BLT 1b
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
20
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
21 # initialize stack pointers for svc modes
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
22 MSR CPSR_cxsf, #(SVC_MODE|NO_INT)
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
23 LDR sp, =svc_stktop
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
24
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
25 BL start
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
26 B .
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
27
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
28 # during startup, kernel stack uses user address, now switch it to kernel addr
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
29 .global jump_stack
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
30 jump_stack:
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
31 MOV r0, sp
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
32 ADD r0, r0, #KERNBASE
Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
parents:
diff changeset
33 MOV sp, r0
11
mir3636
parents: 0
diff changeset
34 MOV pc, lr