diff options
Diffstat (limited to 'arch/mn10300/lib/delay.c')
-rw-r--r-- | arch/mn10300/lib/delay.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/arch/mn10300/lib/delay.c b/arch/mn10300/lib/delay.c new file mode 100644 index 000000000000..cce66bc0822d --- /dev/null +++ b/arch/mn10300/lib/delay.c | |||
@@ -0,0 +1,50 @@ | |||
1 | /* MN10300 Short delay interpolation routines | ||
2 | * | ||
3 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. | ||
4 | * Written by David Howells (dhowells@redhat.com) | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or | ||
7 | * modify it under the terms of the GNU General Public Licence | ||
8 | * as published by the Free Software Foundation; either version | ||
9 | * 2 of the Licence, or (at your option) any later version. | ||
10 | */ | ||
11 | #include <linux/module.h> | ||
12 | #include <linux/sched.h> | ||
13 | #include <linux/delay.h> | ||
14 | #include <asm/div64.h> | ||
15 | |||
16 | /* | ||
17 | * basic delay loop | ||
18 | */ | ||
19 | void __delay(unsigned long loops) | ||
20 | { | ||
21 | int d0; | ||
22 | |||
23 | asm volatile( | ||
24 | " bra 1f \n" | ||
25 | " .align 4 \n" | ||
26 | "1: bra 2f \n" | ||
27 | " .align 4 \n" | ||
28 | "2: add -1,%0 \n" | ||
29 | " bne 2b \n" | ||
30 | : "=&d" (d0) | ||
31 | : "0" (loops)); | ||
32 | } | ||
33 | EXPORT_SYMBOL(__delay); | ||
34 | |||
35 | /* | ||
36 | * handle a delay specified in terms of microseconds | ||
37 | */ | ||
38 | void __udelay(unsigned long usecs) | ||
39 | { | ||
40 | signed long ioclk, stop; | ||
41 | |||
42 | /* usecs * CLK / 1E6 */ | ||
43 | stop = __muldiv64u(usecs, MN10300_TSCCLK, 1000000); | ||
44 | stop = TMTSCBC - stop; | ||
45 | |||
46 | do { | ||
47 | ioclk = TMTSCBC; | ||
48 | } while (stop < ioclk); | ||
49 | } | ||
50 | EXPORT_SYMBOL(__udelay); | ||