[PATCH V2 08/10] ARM: OMAP4: Prevent EMU power domain transitioning to OFF when in-use
Jon Hunter
jon-hunter at ti.com
Mon Jul 16 15:38:49 EDT 2012
Hi Paul,
On 07/16/2012 01:38 PM, Paul Walmsley wrote:
> Hi Jon,
>
> On Mon, 16 Jul 2012, Jon Hunter wrote:
>
>> Yes I see that makes sense. However, patch #7 has already changed the
>> mapping of the flags. I had intended that patch #7 and #8 would be
>> applied together. However, I could see that patch #7 can be taken just
>> to eliminate using the SW_SLEEP state. So basically, what I am saying is
>> does patch #7 have any value without #8?
>
> Certainly not as much value as it had before. But my understanding, which
> is possibly incorrect, matches what you wrote in patch #7's description:
>
> "For OMAP4 devices, SW_SLEEP is equivalent to HW_AUTO and NO_SLEEP is
> equivalent to SW_WKUP. The only difference between HW_AUTO and SW_SLEEP
> for OMAP4 devices is that the PRM_IRQSTATUS_MPU.TRANSITION_ST interrupt
> status is set in case of SW_SLEEP transition, and not set in case of
> HW_AUTO transition."
>
> We don't use that PRM_IRQSTATUS_MPU.TRANSITION_ST interrupt bit. So if
> SW_SLEEP and HW_AUTO really have identical meanings otherwise, then I
> suppose we might as well use the one that does what we need with no
> extraneous side-effects? My recollection from a conversation with Benoît
> a few months ago was that this was his view as well.
Yes that is my understanding too. So from that standpoint it is fine to
keep. However, I just wanted to make sure I understood your thinking here.
>> That's fine with me. We can always workaround such issues by adding flags.
>>
>> I can give this a try this week and let you know how it goes.
>
> Okay, great. No rush on my account.
Ok. I have a few items on my plate that keep preventing me from getting
back to this, but what to get this done.
Jon
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