From mboxrd@z Thu Jan 1 00:00:00 1970 From: robert.jarzmik@free.fr (Robert Jarzmik) Date: Tue, 20 Sep 2016 08:18:02 +0200 Subject: [PATCH 3/4] watchdog: sa11x0/pxa: get rid of get_clock_tick_rate References: <1474312335-20997-1-git-send-email-robert.jarzmik@free.fr> <1474312335-20997-4-git-send-email-robert.jarzmik@free.fr> <20160919200816.GC29242@roeck-us.net> <20160919223616.GN1041@n2100.armlinux.org.uk> <0909debb-f7df-648b-95d2-23b535e5b299@roeck-us.net> Message-ID: <87h99bdrhh.fsf@belgarion.home> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Guenter Roeck writes: > On 09/19/2016 03:36 PM, Russell King - ARM Linux wrote: >> On Mon, Sep 19, 2016 at 01:08:16PM -0700, Guenter Roeck wrote: >>> On Mon, Sep 19, 2016 at 09:12:14PM +0200, Robert Jarzmik wrote: >>>> The OS timer rate used for the watchdog can now be fetched from the >>>> standard clock API. This will remove the last user of >>>> get_clock_tick_rate() in both pxa and sa11x0 architectures. >>>> >>>> Signed-off-by: Robert Jarzmik >>> >>> Did you test this ? Potential problem, if built into the kernel, could be that >>> the clocks might not be ready by the time the driver is instantiated. Unless >>> this is converted to a platform driver, it won't be able to handle a >>> -EPROBE_DEFER from the clock subsystem. >> >> Really not a problem at all. The OSTIMER0 is required for the system >> tick, and if that's not present, the kernel will be without any kind >> of time keeping, so a missing watchdog driver is the least of the >> problems. >> >> Therefore, both PXA and SA11x0 register their clocks really early to >> ensure that OSTIMER0 is available by the time_init() stage, which is >> way before driver probe time. >> > > You are right. And, at least in qemu, it actually works. Hi Guenter, Yes, it was tested on pxa25x (lubbock) and pxa27x (mainstone). Cheers. -- Robert