From mboxrd@z Thu Jan 1 00:00:00 1970 From: Santosh Shilimkar Subject: Re: [PATCH] ARM: OMAP4: PM: Avoid expensive cpu_suspend() path for all CPU power states except off Date: Tue, 12 Feb 2013 10:25:09 +0530 Message-ID: <5119CB2D.9040001@ti.com> 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> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from devils.ext.ti.com ([198.47.26.153]:34141 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760247Ab3BLEx7 (ORCPT ); Mon, 11 Feb 2013 23:53:59 -0500 In-Reply-To: <87d2wazep6.fsf@linaro.org> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Kevin Hilman Cc: linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org 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. Regards, Santosh