linux.git/arch/powerpc/kernel/time.c, branch v4.16

powerpc/64: Rename soft_enabled to irq_soft_mask

2018-01-19T11:37:01+00:00

Rename the paca->soft_enabled to paca->irq_soft_mask as it is no
longer used as a flag for interrupt state, but a mask.

Signed-off-by: Madhavan Srinivasan 
Signed-off-by: Michael Ellerman

powerpc/64: Implement and use soft_enabled_return API

2018-01-19T11:36:59+00:00

Add a new wrapper function, soft_enabled_return(), added to return
paca->soft_enabled value.

Signed-off-by: Madhavan Srinivasan 
Signed-off-by: Michael Ellerman

powerpc/64: Move set_soft_enabled() and rename

2018-01-19T11:36:58+00:00

Move set_soft_enabled() from powerpc/kernel/irq.c to asm/hw_irq.c, to
encourage updates to paca->soft_enabled done via these access
function. Add "memory" clobber to hint compiler since
paca->soft_enabled memory is the target here.

Renaming it as soft_enabled_set() will make namespaces works better as
prefix than a postfix when new soft_enabled manipulation functions are
introduced.

Reviewed-by: Nicholas Piggin 
Signed-off-by: Madhavan Srinivasan 
Signed-off-by: Michael Ellerman

powerpc/64: Add #defines for paca->soft_enabled flags

2018-01-19T11:36:56+00:00

Two #defines IRQS_ENABLED and IRQS_DISABLED are added to be used when
updating paca->soft_enabled. Replace the hardcoded values used when
updating paca->soft_enabled with IRQ_(EN|DIS)ABLED #define. No logic
change.

Reviewed-by: Nicholas Piggin 
Signed-off-by: Madhavan Srinivasan 
Signed-off-by: Michael Ellerman

powerpc: use spin loop primitives in some functions

2017-07-02T10:40:24+00:00

Use the different spin loop primitives in some simple powerpc
spin loops, including those which will spin as a common case.

This will help to test the spin loop primitives before more
conversions are done.

Signed-off-by: Nicholas Piggin 
[mpe: Add some includes of ]
Signed-off-by: Michael Ellerman

powerpc: Convert VDSO update function to use new update_vsyscall interface

2017-06-22T06:26:23+00:00

This converts the powerpc VDSO time update function to use the new
interface introduced in commit 576094b7f0aa ("time: Introduce new
GENERIC_TIME_VSYSCALL", 2012-09-11).  Where the old interface gave
us the time as of the last update in seconds and whole nanoseconds,
with the new interface we get the nanoseconds part effectively in
a binary fixed-point format with tk->tkr_mono.shift bits to the
right of the binary point.

With the old interface, the fractional nanoseconds got truncated,
meaning that the value returned by the VDSO clock_gettime function
would have about 1ns of jitter in it compared to the value computed
by the generic timekeeping code in the kernel.

The powerpc VDSO time functions (clock_gettime and gettimeofday)
already work in units of 2^-32 seconds, or 0.23283 ns, because that
makes it simple to split the result into seconds and fractional
seconds, and represent the fractional seconds in either microseconds
or nanoseconds.  This is good enough accuracy for now, so this patch
avoids changing how the VDSO works or the interface in the VDSO data
page.

This patch converts the powerpc update_vsyscall_old to be called
update_vsyscall and use the new interface.  We convert the fractional
second to units of 2^-32 seconds without truncating to whole nanoseconds.
(There is still a conversion to whole nanoseconds for any legacy users
of the vdso_data/systemcfg stamp_xtime field.)

In addition, this improves the accuracy of the computation of tb_to_xs
for those systems with high-frequency timebase clocks (>= 268.5 MHz)
by doing the right shift in two parts, one before the multiplication and
one after, rather than doing the right shift before the multiplication.
(We can't do all of the right shift after the multiplication unless we
use 128-bit arithmetic.)

Signed-off-by: Paul Mackerras 
Acked-by: John Stultz 
Signed-off-by: Michael Ellerman

powerpc/time: Fix tracing in time.c

2017-06-21T10:37:27+00:00

Since trace_clock is in a different file and already marked with notrace,
enable tracing in time.c by removing it from the disabled list in Makefile.
Also annotate clocksource read functions and sched_clock with notrace.

Testing: Timer and ftrace selftests run with different trace clocks.

Acked-by: Naveen N. Rao 
Signed-off-by: Santosh Sivaraj 
Signed-off-by: Michael Ellerman

powerpc/[booke|4xx]: Don't clobber TCR[WP] when setting TCR[DIE]

2017-05-30T04:59:51+00:00

Prevent a kernel panic caused by unintentionally clearing TCR watchdog
bits. At this point in the kernel boot, the watchdog may have already
been enabled by u-boot. The original code's attempt to write to the TCR
register results in an inadvertent clearing of the watchdog
configuration bits, causing the 476 to reset.

Signed-off-by: Ivan Mikhaylov 
Signed-off-by: Michael Ellerman

powerpc/time: Set ->min_delta_ticks and ->max_delta_ticks

2017-04-14T20:11:10+00:00

In preparation for making the clockevents core NTP correction aware,
all clockevent device drivers must set ->min_delta_ticks and
->max_delta_ticks rather than ->min_delta_ns and ->max_delta_ns: a
clockevent device's rate is going to change dynamically and thus, the
ratio of ns to ticks ceases to stay invariant.

Make the powerpc arch's clockevent driver initialize these fields properly.

This patch alone doesn't introduce any change in functionality as the
clockevents core still looks exclusively at the (untouched) ->min_delta_ns
and ->max_delta_ns. As soon as this has changed, a followup patch will
purge the initialization of ->min_delta_ns and ->max_delta_ns from this
driver.

Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: Daniel Lezcano 
Cc: Richard Cochran 
Cc: Prarit Bhargava 
Cc: Stephen Boyd 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: Oliver O'Halloran 
Cc: linuxppc-dev@lists.ozlabs.org
Acked-by: Michael Ellerman  (powerpc)
Signed-off-by: Nicolai Stange 
Signed-off-by: John Stultz

sched/headers: Prepare to move cputime functionality from into

2017-03-02T07:42:39+00:00

Introduce a trivial, mostly empty  header
to prepare for the moving of cputime functionality out of sched.h.

Update all code that relies on these facilities.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar