diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/x86/include/asm/mach_timer.h | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/x86/include/asm/mach_timer.h')
-rw-r--r-- | kernel/arch/x86/include/asm/mach_timer.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/kernel/arch/x86/include/asm/mach_timer.h b/kernel/arch/x86/include/asm/mach_timer.h new file mode 100644 index 000000000..88d0c3c74 --- /dev/null +++ b/kernel/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 \ + ((PIT_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 */ |