From: Kevin Hilman <khilman@ti.com>
To: Paul Walmsley <paul@pwsan.com>
Cc: NeilBrown <neilb@suse.de>, Joe Woodward <jw@terrafix.co.uk>,
t-kristo@ti.com, govindraj.r@ti.com, linux-omap@vger.kernel.org
Subject: Re: DSS2/PM on 3.2 broken?
Date: Fri, 13 Jan 2012 14:37:01 -0800 [thread overview]
Message-ID: <87lipbp6uq.fsf@ti.com> (raw)
In-Reply-To: <87hazzquhb.fsf@ti.com> (Kevin Hilman's message of "Fri, 13 Jan 2012 11:21:20 -0800")
Kevin Hilman <khilman@ti.com> writes:
[...]
>> From: Paul Walmsley <paul@pwsan.com>
>> Date: Fri, 13 Jan 2012 02:10:30 -0700
>> Subject: [PATCH] ARM: OMAP3: PM: allow MPU to enter low-power states even
>> when the UART is active
>>
>> For some reason, both the existing OMAP3 PM code and the OMAP3 CPUIdle
>> driver prevent the MPU powerdomain from entering low-power modes when
>> any UART isn't asleep. Possibly it is intended to minimize the ARM
>> wakeup latency when UART activity arrives, but the UART has a FIFO
>> that should handle this for most cases, with no dropped characters. I
>> may be forgetting something important, though. And CORE/PER low-power
>> states are a different matter entirely.
>
> Just FYI... the UART can_sleep hackery was removed for v3.3 and replaced
> by using a PM QoS constraint:
However, looking closer I see now that the constraint being used in the
mailine driver uses the CPU_DMA_LATENCY QoS constraint, which is preventing
deeper C states as well just like the current code (before your patch),
so an similar fix will still be needed for mainline.
Kevin
next prev parent reply other threads:[~2012-01-13 22:37 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-09 12:46 DSS2/PM on 3.2 broken? Joe Woodward
2012-01-09 21:08 ` NeilBrown
2012-01-10 9:58 ` Joe Woodward
2012-01-11 13:43 ` Paul Walmsley
2012-01-11 14:22 ` Archit
2012-01-11 15:15 ` Joe Woodward
2012-01-11 15:52 ` Archit
2012-01-11 16:13 ` Joe Woodward
2012-01-11 16:54 ` Archit
2012-01-12 9:28 ` Tomi Valkeinen
2012-01-12 9:30 ` Tomi Valkeinen
2012-01-12 9:51 ` Tomi Valkeinen
2012-01-11 22:59 ` NeilBrown
2012-01-13 10:05 ` Paul Walmsley
2012-01-13 11:20 ` NeilBrown
2012-01-13 11:31 ` Paul Walmsley
2012-01-13 23:09 ` NeilBrown
2012-01-13 23:35 ` Paul Walmsley
2012-01-17 21:24 ` NeilBrown
2012-01-22 0:07 ` Paul Walmsley
2012-01-22 11:30 ` NeilBrown
2012-01-24 10:37 ` OMAP HDQ: was " NeilBrown
2012-01-26 14:19 ` Paul Walmsley
2012-01-27 22:35 ` NeilBrown
2012-01-27 22:58 ` Paul Walmsley
2012-01-28 0:40 ` NeilBrown
2012-01-28 6:02 ` Paul Walmsley
2012-02-01 7:51 ` NeilBrown
2012-02-01 18:36 ` Paul Walmsley
2012-01-18 7:13 ` Tomi Valkeinen
2012-01-18 11:15 ` NeilBrown
2012-01-18 11:42 ` Tomi Valkeinen
2012-01-18 20:30 ` NeilBrown
2012-01-19 10:17 ` Joe Woodward
2012-01-19 10:40 ` Tomi Valkeinen
2012-01-19 11:29 ` Joe Woodward
2012-01-19 11:36 ` Tomi Valkeinen
2012-01-19 12:21 ` Joe Woodward
2012-01-19 14:52 ` Tomi Valkeinen
2012-01-19 19:37 ` Kevin Hilman
2012-01-19 21:05 ` NeilBrown
2012-01-20 0:22 ` Kevin Hilman
2012-01-21 12:12 ` NeilBrown
2012-01-23 22:11 ` Kevin Hilman
2012-01-25 0:32 ` NeilBrown
2012-01-13 11:34 ` Govindraj
2012-01-13 13:23 ` Paul Walmsley
2012-01-13 19:21 ` Kevin Hilman
2012-01-13 22:37 ` Kevin Hilman [this message]
2012-01-13 23:06 ` Paul Walmsley
2012-01-13 23:34 ` Paul Walmsley
2012-01-14 1:17 ` NeilBrown
2012-01-14 1:28 ` Paul Walmsley
2012-01-13 23:39 ` Paul Walmsley
2012-01-13 11:19 ` Paul Walmsley
2012-01-11 13:32 ` Paul Walmsley
2012-01-12 16:42 ` Tomi Valkeinen
2012-01-12 22:40 ` Kevin Hilman
2012-01-13 5:29 ` Tomi Valkeinen
2012-01-13 19:30 ` Kevin Hilman
2012-01-16 11:11 ` Tomi Valkeinen
2012-01-19 19:24 ` Kevin Hilman
2012-01-20 7:16 ` Tomi Valkeinen
2012-01-20 18:06 ` Kevin Hilman
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