clocksource: arch_timer: Fix code to use physical timers when requested
This is a bug fix for using physical arch timers when the arch_timer_use_virtual boolean is false. It restores the arch_counter_get_cntpct() function after removal in 0d651e4e "clocksource: arch_timer: use virtual counters" We need this on certain ARMv7 systems which are architected like this: * The firmware doesn't know and doesn't care about hypervisor mode and we don't want to add the complexity of hypervisor there. * The firmware isn't involved in SMP bringup or resume. * The ARCH timer come up with an uninitialized offset between the virtual and physical counters. Each core gets a different random offset. * The device boots in "Secure SVC" mode. * Nothing has touched the reset value of CNTHCTL.PL1PCEN or CNTHCTL.PL1PCTEN (both default to 1 at reset) One example of such as system is RK3288 where it is much simpler to use the physical counter since there's nobody managing the offset and each time a core goes down and comes back up it will get reinitialized to some other random value. Fixes: 0d651e4e ("clocksource: arch_timer: use virtual counters") Cc: stable@vger.kernel.org Signed-off-by:Sonny Rao <sonnyrao@chromium.org> Acked-by:
Catalin Marinas <catalin.marinas@arm.com> Acked-by:
Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by:
Olof Johansson <olof@lixom.net>
parent
f114040e
Please register or sign in to comment