Re: OMAP3 DSP MMU fault + off mode issue

[Kevin Hilman <khilman@deeprootsystems.com>]

venki kaps <venkiece2005@gmail.com> writes:

> On Tue, Sep 14, 2010 at 8:54 PM, venki kaps <venkiece2005@gmail.com> wrote:
>> On Tue, Sep 14, 2010 at 1:28 AM, venki kaps <venkiece2005@gmail.com> wrote:
>>> Dear all,
>>>
>>> I have been facing an issue with OMAP3 PM with DSP MMU Fault (Kernel 2.6.32).
>>>
>>> The issue is describing as below mentioned way,
>>>        1). The Device is getting DSP MMU Fault when playing MP4 video clip.
>>>
>>> The system is not hitting off mode in the below scenario,
>>>        2). System boot ->play mp4 clip ->DSP MMU Fault -> allow off
>>> mode -----------> Never hits off mode
>>>
>>> But surprisingly the system is hitting off mode in the below scenario,
>>>       3). System boot ->allow off mode ->play mp4 clip ->DSP MMU
>>> Fault -> allow off mode -----------> perfectly works
>>>
>>>
>>>  - Could you please describe the root cause about the above issues 1 & 2?
>>>  - How could solve the above issues?
>>
>> I have found the issue with UART3.
>> In System configuration register (SYSC),-
>>             IDLEMODE  - Smart idle -------> working scenario  ------>
>> system hits off mode.
>>             IDLEMODE  - No idle -------> Non working scenario
>> ------> system never hits off mode.
>>
>> Could you please explain why UART3 is not able to hit smart idle after
>> DSP MMU fault ( System boot ->play mp4 clip ->DSP MMU Fault -> allow
>> off -----------> Never hits off mode).,
>
> My problem is resolved.GPtimer7 was not reset during the MMU FAULT
> occurrence before the first power cycle.
> So this pending interrupt is preventing the system sleep entry.
> Now it works fine after resetting Gptimer7 in pm suspend path.

Sounds like a patch is needed for DSPBridge who manages that timer.

Kevin