]> git.baikalelectronics.ru Git - kernel.git/commit
clocksource: exynos_mct: Don't reset the counter during boot and resume
authorChirantan Ekbote <chirantan@chromium.org>
Wed, 11 Jun 2014 15:18:48 +0000 (00:18 +0900)
committerKukjin Kim <kgene.kim@samsung.com>
Mon, 16 Jun 2014 15:23:29 +0000 (00:23 +0900)
commitccdf57d1eaa6e300bb142226bd8fa6e33be3d4af
tree1f0447c05960c840b5d42807b783dd6bdf181161
parent91b3d7993abd1bf8147c92a0577b62ebaa242d81
clocksource: exynos_mct: Don't reset the counter during boot and resume

Unfortunately on some exynos systems, resetting the mct counter also
resets the architected timer counter.  This can cause problems if the
architected timer driver has already been initialized because the kernel
will think that the counter has wrapped around, causing a big jump in
printk timestamps and delaying any scheduled clock events until the
counter reaches the value it had before it was reset.

The kernel code makes no assumptions about the initial value of the mct
counter so there is no reason from a software perspective to clear the
counter before starting it.  This also fixes the problems described in
the previous paragraph.

Cc: Olof Johansson <olof@lixom.net>
Cc: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Chirantan Ekbote <chirantan@chromium.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
drivers/clocksource/exynos_mct.c