linux/arch/x86
Chen Yu 886123fb3a x86/tsc: Read all ratio bits from MSR_PLATFORM_INFO
Currently we read the tsc radio: ratio = (MSR_PLATFORM_INFO >> 8) & 0x1f;

Thus we get bit 8-12 of MSR_PLATFORM_INFO, however according to the SDM
(35.5), the ratio bits are bit 8-15.

Ignoring the upper bits can result in an incorrect tsc ratio, which causes the
TSC calibration and the Local APIC timer frequency to be incorrect.

Fix this problem by masking 0xff instead.

[ tglx: Massaged changelog ]

Fixes: 7da7c15613 "x86, tsc: Add static (MSR) TSC calibration on Intel Atom SoCs"
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: stable@vger.kernel.org
Cc: Bin Gao <bin.gao@intel.com>
Cc: Len Brown <lenb@kernel.org>
Link: http://lkml.kernel.org/r/1462505619-5516-1-git-send-email-yu.c.chen@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-05-06 11:50:50 +02:00
..
boot x86/build: Build compressed x86 kernels as PIE 2016-03-29 12:51:12 +02:00
configs Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2016-03-17 11:33:45 -07:00
crypto crypto: sha1-mb - use corrcet pointer while completing jobs 2016-04-15 22:13:56 +08:00
entry Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 09:47:32 -07:00
events perf/x86/intel: Fix incorrect lbr_sel_mask value 2016-04-28 10:32:43 +02:00
ia32 Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:05:40 -08:00
include Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-04-28 20:19:04 -07:00
kernel x86/tsc: Read all ratio bits from MSR_PLATFORM_INFO 2016-05-06 11:50:50 +02:00
kvm perf/x86/intel/pt: Don't die on VMXON 2016-04-28 10:32:42 +02:00
lguest Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-14 17:58:53 -07:00
lib Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 09:47:32 -07:00
math-emu Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:05:40 -08:00
mm Revert "x86/mm/32: Set NX in __supported_pte_mask before enabling paging" 2016-04-26 19:52:57 +02:00
net x86/asm/bpf: Create stack frames in bpf_jit.S 2016-02-24 08:35:44 +01:00
oprofile Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 09:47:32 -07:00
pci PCI changes for the v4.6 merge window: 2016-03-16 14:45:55 -07:00
platform Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 09:47:32 -07:00
power x86/asm/power: Create stack frames in hibernate_asm_64.S 2016-02-24 08:35:43 +01:00
purgatory Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 09:47:32 -07:00
ras x86/topology: Fix AMD core count 2016-03-29 10:45:04 +02:00
realmode kernel: add kcov code coverage 2016-03-22 15:36:02 -07:00
tools
um Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-03-19 10:05:34 -07:00
video x86/video: Don't assume all FB devices are PCI devices 2016-03-15 11:08:26 +01:00
xen xen/qspinlock: Don't kick CPU if IRQ is not initialized 2016-04-23 13:40:02 +02:00
.gitignore
Kbuild perf/x86: Move perf_event.c ............... => x86/events/core.c 2016-02-09 10:23:49 +01:00
Kconfig Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 10:02:14 -07:00
Kconfig.cpu x86/Kconfig/cpus: Fix/complete CPU type help texts 2015-10-21 11:12:56 +02:00
Kconfig.debug Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-15 09:32:27 -07:00
Makefile Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2015-11-04 09:11:12 -08:00
Makefile_32.cpu
Makefile.um