From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: Fail to enter retention Date: Mon, 17 Nov 2014 12:38:08 -0800 Message-ID: <20141117203808.GH7046@atomide.com> References: <20141117162209.GE7046@atomide.com> <20141117180944.GG7046@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mho-03-ewr.mailhop.org ([204.13.248.66]:46184 "EHLO mho-01-ewr.mailhop.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752045AbaKQUic (ORCPT ); Mon, 17 Nov 2014 15:38:32 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Ran Shalit Cc: linux-omap@vger.kernel.org * Ran Shalit [141117 11:48]: > >You need to look if you have some devices blocking deeper > >idle states in cm_idlest*_core and cm_idlest_per registers. > > >The device will automatically idle whatever it can if there > >are no blockers. I believe at least EHCI still is blocking, > >and MUSB if configured and cable connected. > > I'll check the registers value, should I then try to modify this > registers in order to get into retention ? No, those are read-only status registers. You need idle the drivers that show as blocking in those registers. > I will still have to disable serial right ? Maybe some kernel process > which run in background prevents retention ? Yes otherwise the UART bits will show as blocking in those registers. > Is there some simple way to debug this or do I need to modify these registers ? Just printing them out in the idle loop most likely will give you the info you need. Regards, Tony