1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
|
/* SPDX-License-Identifier: GPL-2.0+ */
/*
* (C) Copyright 2000, 2001
* Erik Theisen, Wave 7 Optics, etheisen@mindspring.com.
* base on code by
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*/
#include <ppc_asm.tmpl>
#include <ppc_defs.h>
#include <config.h>
/*
* unsigned long long get_ticks(void);
*
* read timebase as "long long"
*/
.globl get_ticks
get_ticks:
1: mftbu r3
mftb r4
mftbu r5
cmp 0,r3,r5
bne 1b
blr
/*
* Delay for a number of ticks
*/
.globl wait_ticks
wait_ticks:
stwu r1, -16(r1)
mflr r0 /* save link register */
stw r0, 20(r1) /* Use r0 or GDB will be unhappy */
stw r14, 12(r1) /* save used registers */
stw r15, 8(r1)
mr r14, r3 /* save tick count */
bl get_ticks /* Get start time */
/* Calculate end time */
addc r14, r4, r14 /* Compute end time lower */
addze r15, r3 /* and end time upper */
#if defined(CONFIG_WATCHDOG) || defined(CONFIG_HW_WATCHDOG)
bl schedule /* Trigger watchdog, if needed */
#endif
1: bl get_ticks /* Get current time */
subfc r4, r4, r14 /* Subtract current time from end time */
subfe. r3, r3, r15
bge 1b /* Loop until time expired */
lwz r15, 8(r1) /* restore saved registers */
lwz r14, 12(r1)
lwz r0, 20(r1)
addi r1,r1,16
mtlr r0
blr
|