alpha: Reorganize rtc handling
Discontinue use of GENERIC_CMOS_UPDATE; rely on the RTC subsystem.
The marvel platform requires that the rtc only be touched from the
boot cpu. This had been partially implemented with hooks for
get/set_rtc_time, but read/update_persistent_clock were not handled.
Move the hooks from the machine_vec to a special rtc_class_ops struct.
We had read_persistent_clock managing the epoch against which the
rtc hw is based, but this didn't apply to get_rtc_time or set_rtc_time.
This resulted in incorrect values when hwclock(8) gets involved.
Allow the epoch to be set from the kernel command-line, overriding
the autodetection, which is doomed to fail in 2020. Further, by
implementing the rtc ioctl function, we can expose this epoch to
userland.
Elide the alarm functions that RTC_DRV_CMOS implements. This was
highly questionable on Alpha, since the interrupt is used by the
system timer.
Signed-off-by: Richard Henderson <rth@twiddle.net>
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 15f166a..0077302 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -626,7 +626,7 @@
config RTC_DRV_CMOS
tristate "PC-style 'CMOS'"
- depends on X86 || ALPHA || ARM || M32R || ATARI || PPC || MIPS || SPARC64
+ depends on X86 || ARM || M32R || ATARI || PPC || MIPS || SPARC64
default y if X86
help
Say "yes" here to get direct support for the real time clock
@@ -643,6 +643,14 @@
This driver can also be built as a module. If so, the module
will be called rtc-cmos.
+config RTC_DRV_ALPHA
+ bool "Alpha PC-style CMOS"
+ depends on ALPHA
+ default y
+ help
+ Direct support for the real-time clock found on every Alpha
+ system, specifically MC146818 compatibles. If in doubt, say Y.
+
config RTC_DRV_VRTC
tristate "Virtual RTC for Intel MID platforms"
depends on X86_INTEL_MID