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ARM: at91: drop AT91_TIMER_HZ 

Drop AT91_TIMER_HZ as this can be handled using HZ_FIXED. Initial help message
was:

On AT91rm9200 chips where you're using a system clock derived
from the 32768 Hz hardware clock, this tick rate should divide
it exactly: use a power-of-two value, such as 128 or 256, to
reduce timing errors caused by rounding.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
This commit is contained in:
Alexandre Belloni 2015-03-13 22:57:24 +01:00 committed by Nicolas Ferre
parent 23b8408246
commit 1164f672d7
2 changed files with 1 additions and 19 deletions
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2
arch/arm/Kconfig
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@ -1502,7 +1502,7 @@ config HZ_FIXED
int
default 200 if ARCH_EBSA110 || ARCH_S3C24XX || \
ARCH_S5PV210 || ARCH_EXYNOS4
default AT91_TIMER_HZ if ARCH_AT91
default 128 if SOC_AT91RM9200
default SHMOBILE_TIMER_HZ if ARCH_SHMOBILE_LEGACY
default 0

18
arch/arm/mach-at91/Kconfig
View File

@ -103,22 +103,4 @@ config SOC_SAMA5
select SOC_SAM_V7
select SRAM if PM
comment "Atmel SoCs Feature Selections"
config AT91_TIMER_HZ
int "Kernel HZ (jiffies per second)"
range 32 1024
depends on ARCH_AT91
default "128" if SOC_AT91RM9200
default "100"
help
On AT91rm9200 chips where you're using a system clock derived
from the 32768 Hz hardware clock, this tick rate should divide
it exactly: use a power-of-two value, such as 128 or 256, to
reduce timing errors caused by rounding.
On AT91sam926x chips, or otherwise when using a higher precision
system clock (of at least several MHz), rounding is less of a
problem so it can be safer to use a decimal values like 100.
endif