[PATCH v2 0/3] ARM sched_clock selection enhancements
Rob Herring
robherring2 at gmail.com
Mon Apr 1 16:58:31 EDT 2013
From: Rob Herring <rob.herring at calxeda.com>
In preparation to move more timer initialization to use CLKSRC_OF and
out of the platforms, a way to select the timer used for sched_clock is
needed. This series makes the ARM sched_clock function override-able and
makes the sched_clock setup code prefer higher frequency counters. This
is sufficient at least on ARM Ltd boards to use the 24MHz counter rather
than sp804 and to always use the 64-bit architected timer when present.
This mechanism can be extended to DT properties if needed for any
non-discoverable h/w feature.
Patch 1 is unchanged from the prior version. Patch 2 is completely
rewritten and more simple than the prior version. It simply converts
sched_clock to a function pointer which can be overridden by the
architected timer init. It seems unlikely we will have other 64-bit
timers or not want to use the architected timer.
Rob
Rob Herring (3):
ARM: sched_clock: allow changing to higher frequency counter
ARM: make sched_clock just call a function pointer
ARM: arch_timer: use full 64-bit counter for sched_clock
arch/arm/include/asm/sched_clock.h | 2 ++
arch/arm/kernel/arch_timer.c | 15 ++++++++++-----
arch/arm/kernel/sched_clock.c | 15 +++++++++++++--
3 files changed, 25 insertions(+), 7 deletions(-)
--
1.7.10.4
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