x86, hyperv: Get the local APIC timer frequency from the hypervisor

Browse source

Hyper-V supports a mechanism for retrieving the local APIC frequency.
Use this and bypass the calibration code in the kernel . This would
allow us to boot the Linux kernel as a "modern VM" on Hyper-V where
many of the legacy devices (such as PIT) are not emulated.

I would like to thank Olaf Hering <olaf@aepfle.de>, Jan Beulich <JBeulich@suse.com> and
H. Peter Anvin <h.peter.anvin@intel.com> for their help in this effort.

In this version of the patch, I have addressed Jan's comments.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Link: http://lkml.kernel.org/r/1380554932-9888-1-git-send-email-olaf@aepfle.de
Tested-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

...

This commit is contained in:

K. Y. Srinivasan 2013-09-30 17:28:52 +02:00 • committed by H. Peter Anvin

parent d0e639c9e0

commit 9e7827b5ea

2 changed files with 43 additions and 0 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

19

arch/x86/include/uapi/asm/hyperv.h

View file

24

arch/x86/kernel/cpu/mshyperv.c

View file