Patch "x86/tsc: Add the Intel Denverton Processor to native_calibrate_tsc()" has been added to the 4.9-stable tree

Patch "x86/tsc: Add the Intel Denverton Processor to native_calibrate_tsc()" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    x86/tsc: Add the Intel Denverton Processor to native_calibrate_tsc()

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86-tsc-add-the-intel-denverton-processor-to-native_calibrate_tsc.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Mon Jul  3 13:33:55 CEST 2017
From: Len Brown <len.brown@intel.com>
Date: Fri, 13 Jan 2017 01:11:18 -0500
Subject: x86/tsc: Add the Intel Denverton Processor to native_calibrate_tsc()

From: Len Brown <len.brown@intel.com>


[ Upstream commit 695085b4bc7603551db0b3da897b8bf9893ca218 ]

The Intel Denverton microserver uses a 25 MHz TSC crystal,
so we can derive its exact [*] TSC frequency
using CPUID and some arithmetic, eg.:

  TSC: 1800 MHz (25000000 Hz * 216 / 3 / 1000000)

[*] 'exact' is only as good as the crystal, which should be +/- 20ppm

Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/306899f94804aece6d8fa8b4223ede3b48dbb59c.1484287748.git.len.brown@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/x86/kernel/tsc.c |    1 +
 1 file changed, 1 insertion(+)

--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -694,6 +694,7 @@ unsigned long native_calibrate_tsc(void)
 			crystal_khz = 24000;	/* 24.0 MHz */
 			break;
 		case INTEL_FAM6_SKYLAKE_X:
+		case INTEL_FAM6_ATOM_DENVERTON:
 			crystal_khz = 25000;	/* 25.0 MHz */
 			break;
 		case INTEL_FAM6_ATOM_GOLDMONT:


Patches currently in stable-queue which might be from len.brown@intel.com are

queue-4.9/x86-tsc-add-the-intel-denverton-processor-to-native_calibrate_tsc.patch