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path: root/arch/powerpc/platforms/powernv/opal-rtc.c
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2015-12-27powerpc/powernv: Only delay opal_rtc_read() retry when necessaryMichael Neuling
Only delay opal_rtc_read() when busy and are going to retry. This has the advantage of possibly saving a massive 10ms off booting! Kudos to Stewart for noticing. Signed-off-by: Michael Neuling <mikey@neuling.org> Reviewed-by: Stewart Smith <stewart@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-16powerpc: Remove broken GregorianDay()Daniel Axtens
GregorianDay() is supposed to calculate the day of the week (tm->tm_wday) for a given day/month/year. In that calcuation it indexed into an array called MonthOffset using tm->tm_mon-1. However tm_mon is zero-based, not one-based, so this is off-by-one. It also means that every January, GregoiranDay() will access element -1 of the MonthOffset array. It also doesn't appear to be a correct algorithm either: see in contrast kernel/time/timeconv.c's time_to_tm function. It's been broken forever, which suggests no-one in userland uses this. It looks like no-one in the kernel uses tm->tm_wday either (see e.g. drivers/rtc/rtc-ds1305.c:319). tm->tm_wday is conventionally set to -1 when not available in hardware so we can simply set it to -1 and drop the function. (There are over a dozen other drivers in drivers/rtc that do this.) Found using UBSAN. Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andrew Morton <akpm@linux-foundation.org> # as an example of what UBSan finds. Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: rtc-linux@googlegroups.com Signed-off-by: Daniel Axtens <dja@axtens.net> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-11-17rtc/tpo: Driver to support rtc and wakeup on PowerNV platformNeelesh Gupta
The patch implements the OPAL rtc driver that binds with the rtc driver subsystem. The driver uses the platform device infrastructure to probe the rtc device and register it to rtc class framework. The 'wakeup' is supported depending upon the property 'has-tpo' present in the OF node. It provides a way to load the generic rtc driver in in the absence of an OPAL driver. The patch also moves the existing OPAL rtc get/set time interfaces to the new driver and exposes the necessary OPAL calls using EXPORT_SYMBOL_GPL. Test results: ------------- Host: [root@tul169p1 ~]# ls -l /sys/class/rtc/ total 0 lrwxrwxrwx 1 root root 0 Oct 14 03:07 rtc0 -> ../../devices/opal-rtc/rtc/rtc0 [root@tul169p1 ~]# cat /sys/devices/opal-rtc/rtc/rtc0/time 08:10:07 [root@tul169p1 ~]# echo `date '+%s' -d '+ 2 minutes'` > /sys/class/rtc/rtc0/wakealarm [root@tul169p1 ~]# cat /sys/class/rtc/rtc0/wakealarm 1413274345 [root@tul169p1 ~]# FSP: $ smgr mfgState standby $ rtim timeofday System time is valid: 2014/10/14 08:12:04.225115 $ smgr mfgState ipling $ CC: devicetree@vger.kernel.org CC: tglx@linutronix.de CC: rtc-linux@googlegroups.com CC: a.zummo@towertech.it Signed-off-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc/powernv: Check OPAL RTC calls exists before usingMichael Neuling
Check that the OPAL_RTC_READ token exists before we use the OPAL RTC. Refactors the code a little to merge error paths. This avoids littering the OPAL console with: "OPAL: Called with bad token 3". Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2013-12-05powernv: Remove get/set_rtc_time when they are not presentMichael Neuling
Currently we continue to poll get/set_rtc_time even when we know they are not working. This changes it so that if it fails at boot time we remove the ppc_md get/set_rtc_time hooks so that we don't end up polling known broken calls. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-11powerpc/powernv: More little endian issues in OPAL RTC driverAnton Blanchard
Sparse caught an issue where opal_set_rtc_time was incorrectly byteswapping. Also fix a number of sparse warnings. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-11powerpc/powernv: Fix endian issues in OPAL RTC driverBenjamin Herrenschmidt
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-09-20powerpc/powernv: Add RTC and NVRAM support plus RTAS fallbacksBenjamin Herrenschmidt
Implements OPAL RTC and NVRAM support and wire all that up to the powernv platform. We use RTAS for RTC as a fallback if available. Using RTAS for nvram is not supported yet, pending some rework/cleanup and generalization of the pSeries & CHRP code. We also use RTAS fallbacks for power off and reboot Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>