From mboxrd@z Thu Jan 1 00:00:00 1970 From: khilman@linaro.org (Kevin Hilman) Date: Tue, 12 Feb 2013 07:18:14 -0800 Subject: [PATCH] ARM: OMAP4: PM: Avoid expensive cpu_suspend() path for all CPU power states except off In-Reply-To: <5119CB2D.9040001@ti.com> (Santosh Shilimkar's message of "Tue, 12 Feb 2013 10:25:09 +0530") References: <1360336306-18277-1-git-send-email-santosh.shilimkar@ti.com> <1360336306-18277-3-git-send-email-santosh.shilimkar@ti.com> <87d2wazep6.fsf@linaro.org> <5119CB2D.9040001@ti.com> Message-ID: <87bobpwog9.fsf@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Santosh Shilimkar writes: > On Saturday 09 February 2013 02:49 AM, Kevin Hilman wrote: >> Santosh Shilimkar writes: >> >>> Current CPU PM code code make use of common cpu_suspend() path for all the >>> CPU power states which is not optimal. In fact cpu_suspend() path is needed >>> only when we put CPU power domain to off state where the CPU context is lost. >>> >>> Update the code accordingly so that the expensive cpu_suspend() path >>> can be avoided for the shallow CPU power states like CPU PD INA/CSWR. >>> >>> Cc: Kevin Hilman >>> >>> Reported-by: Richard Woodruff >>> Signed-off-by: Santosh Shilimkar >> >> Looks OK at first glance, but are you sure this is right for the >> various ways both clusters might idle using coupled CPUidle? >> > Yes it is perfectly safe from all C-states. This patch has been part of > the OMAP4/OMAP5 product port for some time. I forgot to send it upstream > some how :( > >> Some description of the testing would be helpful here. >> > Sorry. Should have mentioned it in first place. > Patch is being tested on OMAP4430 (idle/suspend) and OMAP5 with > few out of tree patches. OK, please update changelog with a brief description of how it was tested, and on which platforms. Thanks, Kevin