Query about vexpress_ct_ca9x4 watchdog issue ?

viresh kumar viresh.kumar at st.com
Wed Apr 20 03:16:47 EDT 2011

On 04/20/2011 12:16 PM, bill wrote:
> At 2011-04-20 12:37:03,"viresh kumar" <viresh.kumar at st.com> wrote:
>> On 04/20/2011 07:37 AM, bill wrote:
>>> I read the WdogValue/WdogControl register as specified in SP805TRM, it does not change any way, 
>>> WdogValue     --> 0xf0918000
>>> WdogControl   -->0x3
>>> It seems the value is correct, but watchdog is not triggered.
>>> I am really puzzled about this, can you give me some clue to find the root cause?
>> Hi Bill,
>> It looks that you are also not getting WDT reset after specified timeout? Is it so?
>> So, probably driver is fine as it is tested on SPEAr.
> I have test this driver on SPEAr1310 with drivers/watchdog/coh901327_wdt.c

Sorry i got confused here. Which driver did you test coh901327_wdt.c or SP805.
1310 doesn't have 805, neither have coh901327_wdt. It has cortex watchdog, for which
support is not added for spear.

coh901327_wdt.c is for ST Ericsson's U300 soc.

>> Probably the issue might be with clock rate and clock enable. What is the clock rate
>> for wdt in your platform?
>> Driver calls clk_enable() and clk_get_rate(). Can you please verify that this is
>> working correctly.
> I did check the clock issue, current mach-vexpress use plat-versatile clock implementation
> in plat-versatile/clock.c clk_enable is an empty function;
> so I guess we don't need any clock gating function in mach-vexpress.

The only thing i can think of is clock, as wdt_value is not at all decrementing.


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