[RFC PATCH v9 0/8] Enable ptp_kvm for arm64

From: Jianyong Wu
Date: Mon Dec 09 2019 - 22:40:42 EST

kvm ptp targets to provide high precision time sync between guest
and host in virtualization environment. Here, we enable kvm ptp
for arm64.
This patch set base on [1][2][3]

change log:

from v8 to v9:
(1) move ptp_kvm.h to driver/ptp/
(2) replace license declaration of ptp_kvm.h the same with other
header files in the same directory.

from v7 to v8:
(1) separate adding clocksource id for arm_arch_counter as a
single patch.
(2) update commit message for patch 4/8.
(3) refine patch 7/8 and patch 8/8 to make them more independent.

from v6 to v7:
(1) include the omitted clocksource_id.h in last version.
(2) reorder the header file in patch.
(3) refine some words in commit message to make it more impersonal.

from v5 to v6:
(1) apply Mark's patch[4] to get SMCCC conduit.
(2) add mechanism to recognize current clocksource by add
clocksouce_id value into struct clocksource instead of method in patch-v5.
(3) rename kvm_arch_ptp_get_clock_fn into

from v4 to v5:
(1) remove hvc delay compensasion as it should leave to userspace.
(2) check current clocksource in hvc call service.
(3) expose current clocksource by adding it to
(4) add helper to check if clocksource is arm_arch_counter.
(5) rename kvm_ptp.c to ptp_kvm_common.c

from v3 to v4:
(1) fix clocksource of ptp_kvm to arch_sys_counter.
(2) move kvm_arch_ptp_get_clock_fn into arm_arch_timer.c
(3) subtract cntvoff before return cycles from host.
(4) use ktime_get_snapshot instead of getnstimeofday and
get_current_counterval to return time and counter value.
(5) split ktime and counter into two 32-bit block respectively
to avoid Y2038-safe issue.
(6) set time compensation to device time as half of the delay of
hvc call.
(7) add ARM_ARCH_TIMER as dependency of ptp_kvm for

from v2 to v3:
(1) fix some issues in commit log.
(2) add some receivers in send list.

from v1 to v2:
(1) move arch-specific code from arch/ to driver/ptp/
(2) offer mechanism to inform userspace if ptp_kvm service is
(3) separate ptp_kvm code for arm64 into hypervisor part and
guest part.
(4) add API to expose monotonic clock and counter value.
(5) refine code: remove no necessary part and reconsitution.


Jianyong Wu (6):
psci: let arm_smccc_1_1_invoke available by modules
ptp: Reorganize ptp_kvm modules to make it arch-independent.
clocksource: Add clocksource id for arm arch counter
psci: Add hvc call service for ptp_kvm.
ptp: arm64: Enable ptp_kvm for arm64
kvm: arm64: Add capability check extension for ptp_kvm

Mark Rutland (1):
arm/arm64: smccc/psci: add arm_smccc_1_1_get_conduit()

Thomas Gleixner (1):
time: Add mechanism to recognize clocksource in time_get_snapshot

drivers/clocksource/arm_arch_timer.c | 24 ++++++
drivers/firmware/psci/psci.c | 16 ++++
drivers/ptp/Kconfig | 2 +-
drivers/ptp/Makefile | 1 +
drivers/ptp/ptp_kvm.h | 11 +++
drivers/ptp/ptp_kvm_arm64.c | 53 +++++++++++++
drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} | 77 +++++-------------
drivers/ptp/ptp_kvm_x86.c | 87 +++++++++++++++++++++
include/linux/arm-smccc.h | 30 ++++++-
include/linux/clocksource.h | 6 ++
include/linux/clocksource_ids.h | 13 +++
include/linux/timekeeping.h | 12 +--
include/uapi/linux/kvm.h | 1 +
kernel/time/clocksource.c | 3 +
kernel/time/timekeeping.c | 1 +
virt/kvm/arm/arm.c | 1 +
virt/kvm/arm/psci.c | 22 ++++++
17 files changed, 294 insertions(+), 66 deletions(-)
create mode 100644 drivers/ptp/ptp_kvm.h
create mode 100644 drivers/ptp/ptp_kvm_arm64.c
rename drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} (63%)
create mode 100644 drivers/ptp/ptp_kvm_x86.c
create mode 100644 include/linux/clocksource_ids.h