Peter Zijlstra 30c7e5b123 x86/tsc: Allow TSC calibration without PIT ... Zhang Rui reported that a Surface Pro 4 will fail to boot with lapic=notscdeadline. Part of the problem is that that machine doesn't have a PIT. If, for some reason, the TSC init has to fall back to TSC calibration, it relies on the PIT to be present. Allow TSC calibration to reliably fall back to HPET. The below results in an accurate TSC measurement when forced on a IVB: tsc: Unable to calibrate against PIT tsc: No reference (HPET/PMTIMER) available tsc: Unable to calibrate against PIT tsc: using HPET reference calibration tsc: Detected 2792.451 MHz processor Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: len.brown@intel.com Cc: rui.zhang@intel.com Link: https://lkml.kernel.org/r/20171222092243.333145937@infradead.org		2018-01-14 20:18:23 +01:00
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asm	x86/tsc: Allow TSC calibration without PIT	2018-01-14 20:18:23 +01:00
uapi/asm	Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-12-29 17:02:49 -08:00