diff options
author | Magnus Damm <magnus.damm@gmail.com> | 2010-07-29 14:03:04 +0100 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-07-29 22:32:28 +0100 |
commit | 5da3e714e30d40145f4dd37d79de6bbbcb9e6137 (patch) | |
tree | 791495aeb84cda5559229d6c310446236bbbe1c2 | |
parent | 58c7d9d2e6116ec694a5af5b8a0aca1467673899 (diff) | |
download | blackbird-op-linux-5da3e714e30d40145f4dd37d79de6bbbcb9e6137.tar.gz blackbird-op-linux-5da3e714e30d40145f4dd37d79de6bbbcb9e6137.zip |
ARM: 6277/1: mach-shmobile: Allow users to select HZ, default to 128
Introduce SHMOBILE_TIMER_HZ for SH-Mobile.
Allow users to select HZ on their system to
minimize potential timer drift. Use 128 Hz as
default to work well with the 32768 Hz RCLK.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
-rw-r--r-- | arch/arm/Kconfig | 1 | ||||
-rw-r--r-- | arch/arm/mach-shmobile/Kconfig | 12 |
2 files changed, 13 insertions, 0 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 98922f7d2d12..db4f2ee3a750 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1189,6 +1189,7 @@ config HZ default 200 if ARCH_EBSA110 || ARCH_S3C2410 || ARCH_S5P6440 || ARCH_S5P6442 || ARCH_S5PV210 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER default AT91_TIMER_HZ if ARCH_AT91 + default SHMOBILE_TIMER_HZ if ARCH_SHMOBILE default 100 config THUMB2_KERNEL diff --git a/arch/arm/mach-shmobile/Kconfig b/arch/arm/mach-shmobile/Kconfig index f2b88c5fe142..4c704b4e8b34 100644 --- a/arch/arm/mach-shmobile/Kconfig +++ b/arch/arm/mach-shmobile/Kconfig @@ -70,6 +70,18 @@ endmenu menu "Timer and clock configuration" +config SHMOBILE_TIMER_HZ + int "Kernel HZ (jiffies per second)" + range 32 1024 + default "128" + help + Allows the configuration of the timer frequency. It is customary + to have the timer interrupt run at 1000 Hz or 100 Hz, but in the + case of low timer frequencies other values may be more suitable. + SH-Mobile systems using a 32768 Hz RCLK for clock events may want + to select a HZ value such as 128 that can evenly divide RCLK. + A HZ value that does not divide evenly may cause timer drift. + config SH_TIMER_CMT bool "CMT timer driver" default y |