From: Sonny Rao Date: Mon, 24 Nov 2014 07:02:44 +0000 (-0800) Subject: clocksource: arch_timer: Fix code to use physical timers when requested X-Git-Tag: omap-for-v3.19/fixes-for-merge-window~12^2~2^2~1 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0b46b8a718c6e90910a1b1b0fe797be3c167e186;p=pandora-kernel.git 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: 0d651e4e65e9 ("clocksource: arch_timer: use virtual counters") Cc: stable@vger.kernel.org Signed-off-by: Sonny Rao Acked-by: Catalin Marinas Acked-by: Daniel Lezcano Signed-off-by: Olof Johansson --- Reading git-diff-tree failed