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author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-03-28 23:40:20 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-03-28 23:48:38 +0300 |
commit | 7c730ccdc1188b97f5c8cb690906242c7ed75c22 (patch) | |
tree | 17ccd927e70dadaf59104c53cce892474eb539b2 /arch/x86/include/asm/mach_timer.h | |
parent | 8d735b4148d46446e64d72b22ef0344ee8dc02fa (diff) | |
parent | 82268da1b130f763d22d04f7d016bbf6fc8815c2 (diff) | |
download | linux-7c730ccdc1188b97f5c8cb690906242c7ed75c22.tar.xz |
Merge branch 'percpu-cpumask-x86-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'percpu-cpumask-x86-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (682 commits)
percpu: fix spurious alignment WARN in legacy SMP percpu allocator
percpu: generalize embedding first chunk setup helper
percpu: more flexibility for @dyn_size of pcpu_setup_first_chunk()
percpu: make x86 addr <-> pcpu ptr conversion macros generic
linker script: define __per_cpu_load on all SMP capable archs
x86: UV: remove uv_flush_tlb_others() WARN_ON
percpu: finer grained locking to break deadlock and allow atomic free
percpu: move fully free chunk reclamation into a work
percpu: move chunk area map extension out of area allocation
percpu: replace pcpu_realloc() with pcpu_mem_alloc() and pcpu_mem_free()
x86, percpu: setup reserved percpu area for x86_64
percpu, module: implement reserved allocation and use it for module percpu variables
percpu: add an indirection ptr for chunk page map access
x86: make embedding percpu allocator return excessive free space
percpu: use negative for auto for pcpu_setup_first_chunk() arguments
percpu: improve first chunk initial area map handling
percpu: cosmetic renames in pcpu_setup_first_chunk()
percpu: clean up percpu constants
x86: un-__init fill_pud/pmd/pte
x86: remove vestigial fix_ioremap prototypes
...
Manually merge conflicts in arch/ia64/kernel/irq_ia64.c
Diffstat (limited to 'arch/x86/include/asm/mach_timer.h')
-rw-r--r-- | arch/x86/include/asm/mach_timer.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/x86/include/asm/mach_timer.h b/arch/x86/include/asm/mach_timer.h new file mode 100644 index 000000000000..853728519ae9 --- /dev/null +++ b/arch/x86/include/asm/mach_timer.h @@ -0,0 +1,48 @@ +/* + * Machine specific calibrate_tsc() for generic. + * Split out from timer_tsc.c by Osamu Tomita <tomita@cinet.co.jp> + */ +/* ------ Calibrate the TSC ------- + * Return 2^32 * (1 / (TSC clocks per usec)) for do_fast_gettimeoffset(). + * Too much 64-bit arithmetic here to do this cleanly in C, and for + * accuracy's sake we want to keep the overhead on the CTC speaker (channel 2) + * output busy loop as low as possible. We avoid reading the CTC registers + * directly because of the awkward 8-bit access mechanism of the 82C54 + * device. + */ +#ifndef _ASM_X86_MACH_DEFAULT_MACH_TIMER_H +#define _ASM_X86_MACH_DEFAULT_MACH_TIMER_H + +#define CALIBRATE_TIME_MSEC 30 /* 30 msecs */ +#define CALIBRATE_LATCH \ + ((CLOCK_TICK_RATE * CALIBRATE_TIME_MSEC + 1000/2)/1000) + +static inline void mach_prepare_counter(void) +{ + /* Set the Gate high, disable speaker */ + outb((inb(0x61) & ~0x02) | 0x01, 0x61); + + /* + * Now let's take care of CTC channel 2 + * + * Set the Gate high, program CTC channel 2 for mode 0, + * (interrupt on terminal count mode), binary count, + * load 5 * LATCH count, (LSB and MSB) to begin countdown. + * + * Some devices need a delay here. + */ + outb(0xb0, 0x43); /* binary, mode 0, LSB/MSB, Ch 2 */ + outb_p(CALIBRATE_LATCH & 0xff, 0x42); /* LSB of count */ + outb_p(CALIBRATE_LATCH >> 8, 0x42); /* MSB of count */ +} + +static inline void mach_countup(unsigned long *count_p) +{ + unsigned long count = 0; + do { + count++; + } while ((inb_p(0x61) & 0x20) == 0); + *count_p = count; +} + +#endif /* _ASM_X86_MACH_DEFAULT_MACH_TIMER_H */ |