mirror of
https://github.com/torvalds/linux.git
synced 2024-12-04 18:13:04 +00:00
99306dfc06
Pull x86 timer updates from Thomas Gleixner:
"These updates are related to TSC handling:
- Support platforms which have synchronized TSCs but the boot CPU has
a non zero TSC_ADJUST value, which is considered a firmware bug on
normal systems.
This applies to HPE/SGI UV platforms where the platform firmware
uses TSC_ADJUST to ensure TSC synchronization across a huge number
of sockets, but due to power on timings the boot CPU cannot be
guaranteed to have a zero TSC_ADJUST register value.
- Fix the ordering of udelay calibration and kvmclock_init()
- Cleanup the udelay and calibration code"
* 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tsc: Mark cyc2ns_init() and detect_art() __init
x86/platform/UV: Mark tsc_check_sync as an init function
x86/tsc: Make CONFIG_X86_TSC=n build work again
x86/platform/UV: Add check of TSC state set by UV BIOS
x86/tsc: Provide a means to disable TSC ART
x86/tsc: Drastically reduce the number of firmware bug warnings
x86/tsc: Skip TSC test and error messages if already unstable
x86/tsc: Add option that TSC on Socket 0 being non-zero is valid
x86/timers: Move simple_udelay_calibration() past kvmclock_init()
x86/timers: Make recalibrate_cpu_khz() void
x86/timers: Move the simple udelay calibration to tsc.h
39 lines
1.0 KiB
C
39 lines
1.0 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_X86_TIMER_H
|
|
#define _ASM_X86_TIMER_H
|
|
#include <linux/pm.h>
|
|
#include <linux/percpu.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/math64.h>
|
|
|
|
#define TICK_SIZE (tick_nsec / 1000)
|
|
|
|
unsigned long long native_sched_clock(void);
|
|
extern void recalibrate_cpu_khz(void);
|
|
|
|
extern int no_timer_check;
|
|
|
|
extern bool using_native_sched_clock(void);
|
|
|
|
/*
|
|
* We use the full linear equation: f(x) = a + b*x, in order to allow
|
|
* a continuous function in the face of dynamic freq changes.
|
|
*
|
|
* Continuity means that when our frequency changes our slope (b); we want to
|
|
* ensure that: f(t) == f'(t), which gives: a + b*t == a' + b'*t.
|
|
*
|
|
* Without an offset (a) the above would not be possible.
|
|
*
|
|
* See the comment near cycles_2_ns() for details on how we compute (b).
|
|
*/
|
|
struct cyc2ns_data {
|
|
u32 cyc2ns_mul;
|
|
u32 cyc2ns_shift;
|
|
u64 cyc2ns_offset;
|
|
}; /* 16 bytes */
|
|
|
|
extern void cyc2ns_read_begin(struct cyc2ns_data *);
|
|
extern void cyc2ns_read_end(void);
|
|
|
|
#endif /* _ASM_X86_TIMER_H */
|