• Serge Semin's avatar
    clocksource: dw_apb_timer_of: Fix missing clockevent timers · 156e8548
    Serge Semin authored
    BugLink: https://bugs.launchpad.net/bugs/1884564
    
    [ Upstream commit 6d2e16a3 ]
    
    Commit 10021488 ("clocksource: dw_apb_timer_of: use
    clocksource_of_init") replaced a publicly available driver
    initialization method with one called by the timer_probe() method
    available after CLKSRC_OF. In current implementation it traverses
    all the timers available in the system and calls their initialization
    methods if corresponding devices were either in dtb or in acpi. But
    if before the commit any number of available timers would be installed
    as clockevent and clocksource devices, after that there would be at most
    two. The rest are just ignored since default case branch doesn't do
    anything. I don't see a reason of such behaviour, neither the commit
    message explains it. Moreover this might be wrong if on some platforms
    these timers might be used for different purpose, as virtually CPU-local
    clockevent timers and as an independent broadcast timer. So in order
    to keep the compatibility with the platforms where the order of the
    timers detection has some meaning, lets add the secondly discovered
    timer to be of clocksource/sched_clock type, while the very first and
    the others would provide the clockevents service.
    
    Fixes: 10021488 ("clocksource: dw_apb_timer_of: use clocksource_of_init")
    Signed-off-by: default avatarSerge Semin <Sergey.Semin@baikalelectronics.ru>
    Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
    Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
    Cc: Paul Burton <paulburton@kernel.org>
    Cc: Ralf Baechle <ralf@linux-mips.org>
    Cc: Alessandro Zummo <a.zummo@towertech.it>
    Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
    Cc: Arnd Bergmann <arnd@arndb.de>
    Cc: Rob Herring <robh+dt@kernel.org>
    Cc: linux-mips@vger.kernel.org
    Cc: linux-rtc@vger.kernel.org
    Cc: devicetree@vger.kernel.org
    Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
    Link: https://lore.kernel.org/r/20200521204818.25436-7-Sergey.Semin@baikalelectronics.ruSigned-off-by: default avatarSasha Levin <sashal@kernel.org>
    Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
    Signed-off-by: default avatarKhalid Elmously <khalid.elmously@canonical.com>
    156e8548
dw_apb_timer_of.c 4.07 KB