From 204879e6990d2a57d7a6e26792cec34f97a63c0e Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Fri, 3 Sep 2021 18:28:54 -0700 Subject: [PATCH] coresight: cpu-debug: Control default behavior via Kconfig Debugfs is nice and so are module parameters, but * debugfs doesn't take effect early (e.g., if drivers are locking up before user space gets anywhere) * module parameters either add a lot to the kernel command line, or else take effect late as well (if you build =m and configure in /etc/modprobe.d/) So in the same spirit as these CONFIG_PANIC_ON_OOPS (also available via cmdline or modparam) CONFIG_INTEL_IOMMU_DEFAULT_ON (also available via cmdline) add a new Kconfig option. Module parameters and debugfs can still override. Signed-off-by: Brian Norris Reviewed-by: Leo Yan [Fixed missing double quote in Kconfig title] Link: https://lore.kernel.org/r/20210903182839.1.I20856983f2841b78936134dcf9cdf6ecafe632b9@changeid Signed-off-by: Mathieu Poirier --- drivers/hwtracing/coresight/Kconfig | 13 +++++++++++++ drivers/hwtracing/coresight/coresight-cpu-debug.c | 2 +- 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig index f026e5c0e777..514a9b8086e3 100644 --- a/drivers/hwtracing/coresight/Kconfig +++ b/drivers/hwtracing/coresight/Kconfig @@ -150,6 +150,19 @@ config CORESIGHT_CPU_DEBUG To compile this driver as a module, choose M here: the module will be called coresight-cpu-debug. +config CORESIGHT_CPU_DEBUG_DEFAULT_ON + bool "Enable CoreSight CPU Debug by default" + depends on CORESIGHT_CPU_DEBUG + help + Say Y here to enable the CoreSight Debug panic-debug by default. This + can also be enabled via debugfs, but this ensures the debug feature + is enabled as early as possible. + + Has the same effect as setting coresight_cpu_debug.enable=1 on the + kernel command line. + + Say N if unsure. + config CORESIGHT_CTI tristate "CoreSight Cross Trigger Interface (CTI) driver" depends on ARM || ARM64 diff --git a/drivers/hwtracing/coresight/coresight-cpu-debug.c b/drivers/hwtracing/coresight/coresight-cpu-debug.c index 00de46565bc4..8845ec4b4402 100644 --- a/drivers/hwtracing/coresight/coresight-cpu-debug.c +++ b/drivers/hwtracing/coresight/coresight-cpu-debug.c @@ -105,7 +105,7 @@ static DEFINE_PER_CPU(struct debug_drvdata *, debug_drvdata); static int debug_count; static struct dentry *debug_debugfs_dir; -static bool debug_enable; +static bool debug_enable = IS_ENABLED(CONFIG_CORESIGHT_CPU_DEBUG_DEFAULT_ON); module_param_named(enable, debug_enable, bool, 0600); MODULE_PARM_DESC(enable, "Control to enable coresight CPU debug functionality");