From mboxrd@z Thu Jan 1 00:00:00 1970 From: jouni.hogander@nokia.com (=?utf-8?Q?H=C3=B6gander?= Jouni) Subject: Re: Problems in cpuidle Date: Mon, 09 Mar 2009 12:05:36 +0200 Message-ID: <871vt7ko3z.fsf@trdhcp146196.ntc.nokia.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from smtp.nokia.com ([192.100.105.134]:32410 "EHLO mgw-mx09.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752689AbZCIKGQ convert rfc822-to-8bit (ORCPT ); Mon, 9 Mar 2009 06:06:16 -0400 In-Reply-To: (ext Premi's message of "Fri\, 6 Mar 2009 18\:32\:07 +0100") Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: "ext Premi, Sanjeev" Cc: "linux-omap@vger.kernel.org" "ext Premi, Sanjeev" writes: > While working with cpuidle, I have come across these problems. > I am also working on the solutions, but would be good to hear > more thoughts. > > 1) The flag 'enable_dyn_sleep' is honoured only in omap3_idle_bm_chec= k() > but in the C1 state, omap3_enter_idle() is invoked directly. > So, the system can transition to deeper idle state(s) > > Same is the case with 'sleep_block'. > > Possible Solutions: > a) Call omap3_can_sleep() in omap3_enter_idle(). > This makes omap3_idle_bm_check() redundant; and can be remov= ed. > > b) Make single entry point for all idle states > But would be an overkill for C1 state. > > c) Change omap3_can_sleep() to check for omap_uart_can_sleep() > and omap3_fclks_active() only. > Move check for 'enable_dyn_sleep' and 'sleep_block' into > omap3_enter_idle() > > I believe (c) would be the most optimal. Selecting (c) will break traditional pm_idle. Current plan is to add on= e more C state (C1) which would prevent mpu/core sleep transitions. Then remove fclk_active check completely. --=20 Jouni H=C3=B6gander -- To unsubscribe from this list: send the line "unsubscribe linux-omap" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html