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authorLinus Torvalds <torvalds@woody.osdl.org>2006-12-07 18:40:39 -0500
committerLinus Torvalds <torvalds@woody.osdl.org>2006-12-07 18:40:39 -0500
commitea14fad0d416354a4e9bb1a04f32acba706f9548 (patch)
tree2c8acc5331f189aef1d40ddce3f40d6be9314e77 /arch/arm/mach-pxa/generic.c
parent6ee7e78e7c78d871409ad4df30551c9355be7d0e (diff)
parent6705cda24fad1cb0ac82ac4f312df8ec735b39b0 (diff)
Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (76 commits) [ARM] 4002/1: S3C24XX: leave parent IRQs unmasked [ARM] 4001/1: S3C24XX: shorten reboot time [ARM] 3983/2: remove unused argument to __bug() [ARM] 4000/1: Osiris: add third serial port in [ARM] 3999/1: RX3715: suspend to RAM support [ARM] 3998/1: VR1000: LED platform devices [ARM] 3995/1: iop13xx: add iop13xx support [ARM] 3968/1: iop13xx: add iop13xx_defconfig [ARM] Update mach-types [ARM] Allow gcc to optimise arm_add_memory a little more [ARM] 3991/1: i.MX/MX1 high resolution time source [ARM] 3990/1: i.MX/MX1 more precise PLL decode [ARM] 3986/1: H1940: suspend to RAM support [ARM] 3985/1: ixp4xx clocksource cleanup [ARM] 3984/1: ixp4xx/nslu2: Fix disk LED numbering (take 2) [ARM] 3994/1: ixp23xx: fix handling of pci master aborts [ARM] 3981/1: sched_clock for PXA2xx [ARM] 3980/1: extend the ARM Versatile sched_clock implementation from 32 to 63 bit [ARM] 3979/1: extend the SA11x0 sched_clock implementation from 32 to 63 bit period [ARM] 3978/1: macro to provide a 63-bit value from a 32-bit hardware counter ...
Diffstat (limited to 'arch/arm/mach-pxa/generic.c')
-rw-r--r--arch/arm/mach-pxa/generic.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/arch/arm/mach-pxa/generic.c b/arch/arm/mach-pxa/generic.c
index 45fb2c3bcf82..6ae605857ca9 100644
--- a/arch/arm/mach-pxa/generic.c
+++ b/arch/arm/mach-pxa/generic.c
@@ -25,6 +25,10 @@
25#include <linux/pm.h> 25#include <linux/pm.h>
26#include <linux/string.h> 26#include <linux/string.h>
27 27
28#include <linux/sched.h>
29#include <asm/cnt32_to_63.h>
30#include <asm/div64.h>
31
28#include <asm/hardware.h> 32#include <asm/hardware.h>
29#include <asm/irq.h> 33#include <asm/irq.h>
30#include <asm/system.h> 34#include <asm/system.h>
@@ -41,6 +45,62 @@
41#include "generic.h" 45#include "generic.h"
42 46
43/* 47/*
48 * This is the PXA2xx sched_clock implementation. This has a resolution
49 * of at least 308ns and a maximum value that depends on the value of
50 * CLOCK_TICK_RATE.
51 *
52 * The return value is guaranteed to be monotonic in that range as
53 * long as there is always less than 582 seconds between successive
54 * calls to this function.
55 */
56unsigned long long sched_clock(void)
57{
58 unsigned long long v = cnt32_to_63(OSCR);
59 /* Note: top bit ov v needs cleared unless multiplier is even. */
60
61#if CLOCK_TICK_RATE == 3686400
62 /* 1E9 / 3686400 => 78125 / 288, max value = 32025597s (370 days). */
63 /* The <<1 is used to get rid of tick.hi top bit */
64 v *= 78125<<1;
65 do_div(v, 288<<1);
66#elif CLOCK_TICK_RATE == 3250000
67 /* 1E9 / 3250000 => 4000 / 13, max value = 709490156s (8211 days) */
68 v *= 4000;
69 do_div(v, 13);
70#elif CLOCK_TICK_RATE == 3249600
71 /* 1E9 / 3249600 => 625000 / 2031, max value = 4541295s (52 days) */
72 v *= 625000;
73 do_div(v, 2031);
74#else
75#warning "consider fixing sched_clock for your value of CLOCK_TICK_RATE"
76 /*
77 * 96-bit math to perform tick * NSEC_PER_SEC / CLOCK_TICK_RATE for
78 * any value of CLOCK_TICK_RATE. Max value is in the 80 thousand
79 * years range which is nice, but with higher computation cost.
80 */
81 {
82 union {
83 unsigned long long val;
84 struct { unsigned long lo, hi; };
85 } x;
86 unsigned long long y;
87
88 x.val = v;
89 x.hi &= 0x7fffffff;
90 y = (unsigned long long)x.lo * NSEC_PER_SEC;
91 x.lo = y;
92 y = (y >> 32) + (unsigned long long)x.hi * NSEC_PER_SEC;
93 x.hi = do_div(y, CLOCK_TICK_RATE);
94 do_div(x.val, CLOCK_TICK_RATE);
95 x.hi += y;
96 v = x.val;
97 }
98#endif
99
100 return v;
101}
102
103/*
44 * Handy function to set GPIO alternate functions 104 * Handy function to set GPIO alternate functions
45 */ 105 */
46 106