diff options
Diffstat (limited to 'arch/mips/cavium-octeon/csrc-octeon.c')
-rw-r--r-- | arch/mips/cavium-octeon/csrc-octeon.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/arch/mips/cavium-octeon/csrc-octeon.c b/arch/mips/cavium-octeon/csrc-octeon.c new file mode 100644 index 000000000000..70fd92c31657 --- /dev/null +++ b/arch/mips/cavium-octeon/csrc-octeon.c | |||
@@ -0,0 +1,58 @@ | |||
1 | /* | ||
2 | * This file is subject to the terms and conditions of the GNU General Public | ||
3 | * License. See the file "COPYING" in the main directory of this archive | ||
4 | * for more details. | ||
5 | * | ||
6 | * Copyright (C) 2007 by Ralf Baechle | ||
7 | */ | ||
8 | #include <linux/clocksource.h> | ||
9 | #include <linux/init.h> | ||
10 | |||
11 | #include <asm/time.h> | ||
12 | |||
13 | #include <asm/octeon/octeon.h> | ||
14 | #include <asm/octeon/cvmx-ipd-defs.h> | ||
15 | |||
16 | /* | ||
17 | * Set the current core's cvmcount counter to the value of the | ||
18 | * IPD_CLK_COUNT. We do this on all cores as they are brought | ||
19 | * on-line. This allows for a read from a local cpu register to | ||
20 | * access a synchronized counter. | ||
21 | * | ||
22 | */ | ||
23 | void octeon_init_cvmcount(void) | ||
24 | { | ||
25 | unsigned long flags; | ||
26 | unsigned loops = 2; | ||
27 | |||
28 | /* Clobber loops so GCC will not unroll the following while loop. */ | ||
29 | asm("" : "+r" (loops)); | ||
30 | |||
31 | local_irq_save(flags); | ||
32 | /* | ||
33 | * Loop several times so we are executing from the cache, | ||
34 | * which should give more deterministic timing. | ||
35 | */ | ||
36 | while (loops--) | ||
37 | write_c0_cvmcount(cvmx_read_csr(CVMX_IPD_CLK_COUNT)); | ||
38 | local_irq_restore(flags); | ||
39 | } | ||
40 | |||
41 | static cycle_t octeon_cvmcount_read(void) | ||
42 | { | ||
43 | return read_c0_cvmcount(); | ||
44 | } | ||
45 | |||
46 | static struct clocksource clocksource_mips = { | ||
47 | .name = "OCTEON_CVMCOUNT", | ||
48 | .read = octeon_cvmcount_read, | ||
49 | .mask = CLOCKSOURCE_MASK(64), | ||
50 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | ||
51 | }; | ||
52 | |||
53 | void __init plat_time_init(void) | ||
54 | { | ||
55 | clocksource_mips.rating = 300; | ||
56 | clocksource_set_clock(&clocksource_mips, mips_hpt_frequency); | ||
57 | clocksource_register(&clocksource_mips); | ||
58 | } | ||