diff options
| -rw-r--r-- | arch/mips/Kconfig | 1 | ||||
| -rw-r--r-- | arch/mips/kernel/csrc-r4k.c | 40 |
2 files changed, 41 insertions, 0 deletions
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 2747b1b2d435..f347312ecd74 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1108,6 +1108,7 @@ config CSRC_IOASIC bool config CSRC_R4K + select CLOCKSOURCE_WATCHDOG if CPU_FREQ bool config CSRC_SB1250 diff --git a/arch/mips/kernel/csrc-r4k.c b/arch/mips/kernel/csrc-r4k.c index 437dda64fd7a..edc4afc080fa 100644 --- a/arch/mips/kernel/csrc-r4k.c +++ b/arch/mips/kernel/csrc-r4k.c @@ -6,6 +6,7 @@ * Copyright (C) 2007 by Ralf Baechle */ #include <linux/clocksource.h> +#include <linux/cpufreq.h> #include <linux/init.h> #include <linux/sched_clock.h> @@ -65,6 +66,45 @@ static bool rdhwr_count_usable(void) return false; } +#ifdef CONFIG_CPU_FREQ + +static bool __read_mostly r4k_clock_unstable; + +static void r4k_clocksource_unstable(char *reason) +{ + if (r4k_clock_unstable) + return; + + r4k_clock_unstable = true; + + pr_info("R4K timer is unstable due to %s\n", reason); + + clocksource_mark_unstable(&clocksource_mips); +} + +static int r4k_cpufreq_callback(struct notifier_block *nb, + unsigned long val, void *data) +{ + if (val == CPUFREQ_POSTCHANGE) + r4k_clocksource_unstable("CPU frequency change"); + + return 0; +} + +static struct notifier_block r4k_cpufreq_notifier = { + .notifier_call = r4k_cpufreq_callback, +}; + +static int __init r4k_register_cpufreq_notifier(void) +{ + return cpufreq_register_notifier(&r4k_cpufreq_notifier, + CPUFREQ_TRANSITION_NOTIFIER); + +} +core_initcall(r4k_register_cpufreq_notifier); + +#endif /* !CONFIG_CPU_FREQ */ + int __init init_r4k_clocksource(void) { if (!cpu_has_counter || !mips_hpt_frequency) |