From 55f1ca209d37d7b5a6faf57b23c7341cb7f84ee6 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Corvin=20K=C3=B6hne?= Date: Thu, 8 Dec 2022 08:28:42 +0100 Subject: [PATCH] atrtc: expose power loss as sysctl Exposing the a power loss of the rtc as an sysctl makes it easier to detect an empty cmos battery. Reviewed by: manu MFC after: 1 week Sponsored by: Beckhoff Automation GmbH & Co. KG Differential Revision: https://reviews.freebsd.org/D38325 --- sys/x86/isa/atrtc.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/sys/x86/isa/atrtc.c b/sys/x86/isa/atrtc.c index 33eb9a4bbdf0..81ba400619cc 100644 --- a/sys/x86/isa/atrtc.c +++ b/sys/x86/isa/atrtc.c @@ -62,6 +62,11 @@ __FBSDID("$FreeBSD$"); #include #endif +/* tunable to detect a power loss of the rtc */ +static bool atrtc_power_lost = false; +SYSCTL_BOOL(_machdep, OID_AUTO, atrtc_power_lost, CTLFLAG_RD, &atrtc_power_lost, + false, "RTC lost power on last power cycle (probably caused by an emtpy cmos battery)"); + /* * atrtc_lock protects low-level access to individual hardware registers. * atrtc_time_lock protects the entire sequence of accessing multiple registers @@ -600,6 +605,7 @@ atrtc_gettime(device_t dev, struct timespec *ts) /* Look if we have a RTC present and the time is valid */ if (!(rtcin(RTC_STATUSD) & RTCSD_PWR)) { + atrtc_power_lost = true; device_printf(dev, "WARNING: Battery failure indication\n"); return (EINVAL); }