blob: 52e7a10d7ff8becd559b8548d000fac4176e21ee (
plain) (
blame)
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
|
#ifndef _BLACKFIN_DELAY_H
#define _BLACKFIN_DELAY_H
static inline void __delay(unsigned long loops)
{
/* FIXME: Currently the assembler doesn't recognize Loop Register Clobbers,
uncomment this as soon those are implemented */
/*
__asm__ __volatile__ ( "\t LSETUP (1f,1f) LC0= %0\n\t"
"1:\t NOP;\n\t"
: :"a" (loops)
: "LT0","LB0","LC0");
*/
__asm__ __volatile__("[--SP] = LC0;\n\t"
"[--SP] = LT0;\n\t"
"[--SP] = LB0;\n\t"
"LSETUP (1f,1f) LC0 = %0;\n\t"
"1:\t NOP;\n\t"
"LB0 = [SP++];\n\t"
"LT0 = [SP++];\n\t"
"LC0 = [SP++];\n"
:
:"a" (loops));
}
#include <linux/param.h> /* needed for HZ */
/*
* Use only for very small delays ( < 1 msec). Should probably use a
* lookup table, really, as the multiplications take much too long with
* short delays. This is a "reasonable" implementation, though (and the
* first constant multiplications gets optimized away if the delay is
* a constant)
*/
static inline void udelay(unsigned long usecs)
{
extern unsigned long loops_per_jiffy;
__delay(usecs * loops_per_jiffy / (1000000 / HZ));
}
#endif /* defined(_BLACKFIN_DELAY_H) */
|
