[PATCH 1/2] hwspinlock/omap: enable module before reading SYSSTATUS register

Suman Anna s-anna at ti.com
Thu Jul 24 08:13:37 PDT 2014


Hi Ohad,

On 07/24/2014 08:45 AM, Ohad Ben-Cohen wrote:
> Hi Suman,
> 
> On Thu, Jul 3, 2014 at 2:00 AM, Suman Anna <s-anna at ti.com> wrote:
>> The number of hwspinlocks are determined based on the value read
>> from the IP block's SYSSTATUS register. However, the module may
>> not be enabled and clocked, and the read may result in a bus error.
>>
>> This particular issue is seen rather easily on AM33XX, since the
>> module wakeup is software controlled, and it is disabled out of
>> reset. Make sure the module is enabled and clocked before reading
>> the SYSSTATUS register.
>>
>> Signed-off-by: Suman Anna <s-anna at ti.com>
> ...
>> +       /*
>> +        * runtime PM will make sure the clock of this module is
>> +        * enabled again iff at least one lock is requested
>> +        */
>> +       ret = pm_runtime_put_sync(&pdev->dev);
> 
> Is there a specific reason for using the put_sync variant here? If
> not, let's just use the regular put().

There was no particular reason, you can change it.

> 
> Let me know, and I can do the change while applying these two patches.

Sure, thanks.

regards
Suman



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