From mboxrd@z Thu Jan 1 00:00:00 1970 From: jason@lakedaemon.net (Jason Cooper) Date: Wed, 16 Jul 2014 09:02:51 -0400 Subject: [PATCHv3 1/7] ARM: mvebu: ensure CPU clocks are enabled In-Reply-To: <1404920715-19834-2-git-send-email-thomas.petazzoni@free-electrons.com> References: <1404920715-19834-1-git-send-email-thomas.petazzoni@free-electrons.com> <1404920715-19834-2-git-send-email-thomas.petazzoni@free-electrons.com> Message-ID: <20140716130251.GZ13108@titan.lakedaemon.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Jul 09, 2014 at 05:45:09PM +0200, Thomas Petazzoni wrote: > In the Armada XP SMP support code, we are reading the clock frequency > of the booting CPU, and use that to assign the same frequency to the > other CPUs, and we do this while the clocks are disabled. > > However, the CPU clocks are in fact never prepared/enabled, and to > support cpufreq, we now have two code paths to change the frequency of > the CPU clocks in the CPU clock driver: one when the clock is enabled > (dynamic frequency scaling), one when the clock is disabled (adjusting > the CPU frequency before starting the CPU). In order for this to work, > the CPU clocks now have to be prepared and enabled after the initial > synchronization of the clock frequencies is done, so that all future > rate changes of the CPU clocks will trigger a dynamic frequency > scaling transition. > > Signed-off-by: Thomas Petazzoni > --- > arch/arm/mach-mvebu/platsmp.c | 1 + > 1 file changed, 1 insertion(+) Tentatively applied patches 1-3, and 5 to mvebu/soc-cpufreq to get some coverage in -next. thx, Jason.