diff options
author | Bryan Wu <cooloney@kernel.org> | 2008-08-26 22:51:02 -0400 |
---|---|---|
committer | Bryan Wu <cooloney@kernel.org> | 2008-08-26 22:51:02 -0400 |
commit | 639f6571458948b5112be2cf00c0c2c04db2897d (patch) | |
tree | a4dd7af33d0e92c935ba1e904f6fb7e923ac825e /arch/blackfin/include/asm/time.h | |
parent | 3d9b7a5ce534f3963afcf8f4777267e5899fe007 (diff) |
Blackfin arch: move include/asm-blackfin header files to arch/blackfin
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Diffstat (limited to 'arch/blackfin/include/asm/time.h')
-rw-r--r-- | arch/blackfin/include/asm/time.h | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/arch/blackfin/include/asm/time.h b/arch/blackfin/include/asm/time.h new file mode 100644 index 000000000000..ddc43ce38533 --- /dev/null +++ b/arch/blackfin/include/asm/time.h | |||
@@ -0,0 +1,40 @@ | |||
1 | /* | ||
2 | * asm-blackfin/time.h: | ||
3 | * | ||
4 | * Copyright 2004-2008 Analog Devices Inc. | ||
5 | * | ||
6 | * Licensed under the GPL-2 or later. | ||
7 | */ | ||
8 | |||
9 | #ifndef _ASM_BLACKFIN_TIME_H | ||
10 | #define _ASM_BLACKFIN_TIME_H | ||
11 | |||
12 | /* | ||
13 | * The way that the Blackfin core timer works is: | ||
14 | * - CCLK is divided by a programmable 8-bit pre-scaler (TSCALE) | ||
15 | * - Every time TSCALE ticks, a 32bit is counted down (TCOUNT) | ||
16 | * | ||
17 | * If you take the fastest clock (1ns, or 1GHz to make the math work easier) | ||
18 | * 10ms is 10,000,000 clock ticks, which fits easy into a 32-bit counter | ||
19 | * (32 bit counter is 4,294,967,296ns or 4.2 seconds) so, we don't need | ||
20 | * to use TSCALE, and program it to zero (which is pass CCLK through). | ||
21 | * If you feel like using it, try to keep HZ * TIMESCALE to some | ||
22 | * value that divides easy (like power of 2). | ||
23 | */ | ||
24 | |||
25 | #ifndef CONFIG_CPU_FREQ | ||
26 | #define TIME_SCALE 1 | ||
27 | #define __bfin_cycles_off (0) | ||
28 | #define __bfin_cycles_mod (0) | ||
29 | #else | ||
30 | /* | ||
31 | * Blackfin CPU frequency scaling supports max Core Clock 1, 1/2 and 1/4 . | ||
32 | * Whenever we change the Core Clock frequency changes we immediately | ||
33 | * adjust the Core Timer Presale Register. This way we don't lose time. | ||
34 | */ | ||
35 | #define TIME_SCALE 4 | ||
36 | extern unsigned long long __bfin_cycles_off; | ||
37 | extern unsigned int __bfin_cycles_mod; | ||
38 | #endif | ||
39 | |||
40 | #endif | ||