On Thu, Mar 03, 2011 at 10:35:23AM -0800, Kevin Hilman wrote:

"G, Manjunath Kondaiah" [off-list ref] writes:

quoted

This patch series is remaining part of dma hwmod to support pm runtime 
and for handling mstandby mode for all applicable DMA mstandby mode errata.

This is still not runtime-suspending when I use my DMA test in linking
mode.

If I put a large enough period between transfers, it should autosuspend
during transfers.  It seems to do auto-suspend and resume once, but then
it never suspends again.

I tested with my dmatest module[1], and loaded with:

  # insmod ./dmatest.ko linking=1 forever=1 forever_period=1024

Not only does it not auto-suspend between transfers (which I expected),
it also doesn't suspend after removing the module which stops all active
channels.

The normal chaining test cases are executed and which used to show the
proper status. Let me reproduce this issue with your test procedure.

quoted

The alignment for handling mstandby mode errata handling is at:
http://thread.gmane.org/gmane.linux.ports.arm.omap/47398/focus=47426
http://thread.gmane.org/gmane.linux.ports.arm.omap/47479/focus=47537

Testing:
Compile tested for
 - omap1_defconfig
 - omap2plus_defconfig

Boot test on:
 - OMAP1710-H3
 - OMAP2420-H4
 - OMAP3430-LDP

Sorry. It's OMAP3430 Zoom2 and not LDP.

-Manjunath

quoted

 - OMAP3630-Zoom3
 - OMAP4430-Blaze

DMA memory to memory test cases(including chaining) are executed for
all the above boards and for each test case, 
/sys/devices/platform/omap/omap_dma_system.0/power/runtime_status
was verified and after completion of the tests, runtime_status will be 
always suspended.

Apart from that, offmode testing is done for OMAP3430-LDP using the procedure:
echo 1 > /debug/pm_debug/sleep_while_idle
echo 1 > /debug/pm_debug/enable_off_mode
echo 5 > /sys/devices/platform/omap/omap_uart.0/sleep_timeout
echo 5 > /sys/devices/platform/omap/omap_uart.1/sleep_timeout
echo 5 > /sys/devices/platform/omap/omap_uart.2/sleep_timeout

With the above steps, core off mode count gets increasing if the the board
is idle for more than 5 seconds.

Baseline:
Applies cleanly on top of mainline 2.6.38-rc6:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
commit f5412be599602124d2bdd49947b231dd77c0bf99
Author: Linus Torvalds [off-list ref]
Date:   Mon Feb 21 17:25:52 2011 -0800

    Linux 2.6.38-rc6

Note: OMAP1 is tested on top of 2.6.38-rc5 since rc6 is broken for omap1 build

Patch Summary:
==============
G, Manjunath Kondaiah (2):
  OMAP2+: PM: omap device: API's for handling mstandby mode
  OMAP2+: DMA: prevent races while setting M idle mode to nostandby

Manjunath G Kondaiah (1):
  OMAP: PM: DMA: Enable runtime pm

 arch/arm/mach-omap1/dma.c                     |    1 +
 arch/arm/mach-omap2/dma.c                     |   16 ++
 arch/arm/mach-omap2/omap_hwmod.c              |   42 ++++++
 arch/arm/plat-omap/dma.c                      |  190 +++++++++++++++++++++----
 arch/arm/plat-omap/include/plat/dma.h         |    1 +
 arch/arm/plat-omap/include/plat/omap_device.h |    2 +
 arch/arm/plat-omap/include/plat/omap_hwmod.h  |    4 +-
 arch/arm/plat-omap/omap_device.c              |   64 +++++++++
 8 files changed, 293 insertions(+), 27 deletions(-)