From 46fd5c6b3059462131caa4d52691c9c5666c3223 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Mon, 27 Jun 2016 17:30:13 +0100 Subject: clocksource/drivers/arm_arch_timer: Control the evtstrm via the cmdline Disabling the eventstream can be useful for both remotely debugging a deployed production system and development of code using WFE-based polling loops. Whilst this can currently be controlled via a Kconfig option (CONFIG_ARM_ARCH_TIMER_EVTSTREAM), it's often desirable to toggle the feature on the command line, so this patch adds a new command-line option ("clocksource.arm_arch_timer.evtstrm") to do just that. The default behaviour is determined based on CONFIG_ARM_ARCH_TIMER_EVTSTREAM. Cc: Marc Zyngier Cc: Mark Rutland Signed-off-by: Will Deacon Signed-off-by: Daniel Lezcano --- Documentation/kernel-parameters.txt | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 82b42c958d1c..2c92f1df7c69 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -687,6 +687,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted. [SPARC64] tick [X86-64] hpet,tsc + clocksource.arm_arch_timer.evtstrm= + [ARM,ARM64] + Format: + Enable/disable the eventstream feature of the ARM + architected timer so that code using WFE-based polling + loops can be debugged more effectively on production + systems. + clearcpuid=BITNUM [X86] Disable CPUID feature X for the kernel. See arch/x86/include/asm/cpufeatures.h for the valid bit -- cgit v1.2.3